Kitchener WWTP Phase 3 Upgrades Preliminary Design DRAFT

Prepared by: AECOM 105 Commerce Valley Drive West, Floor 7 905 886 7022 tel Markham, ON, Canada L3T 7W3 905 886 9494 fax www.aecom.com Project Number: 60159482 Date: August, 2012

Water

Regional Municipality of Waterloo

Kitchener WWTP Phase 3 Upgrades Preliminary Design DRAFT Final Report

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Regional Municipality of Waterloo Kitchener WWTP Upgrades

Preliminary Design DRAFT Final Report

AECOM: 2012-01-06 © 2009-2012 AECOM Canada Ltd. All Rights Reserved. RPT-2012-08-29 - Draft Final PDR- 60159482.Docx

Statement of Qualifications and Limitations The attached Report (the “Report”) has been prepared by AECOM Canada Ltd. (“Consultant”) for the benefit of the Regional Municipality of Waterloo (“Client”) in accordance with the agreement between Consultant and Client, including the scope of work detailed therein (the “Agreement”). The information, data, recommendations and conclusions contained in the Report (collectively, the “Information”):

is subject to the scope, schedule, and other constraints and limitations in the Agreement and the qualifications contained in the Report (the “Limitations”);

represents Consultant’s professional judgement in light of the Limitations and industry standards for the preparation of similar reports;

may be based on information provided to Consultant which has not been independently verified; has not been updated since the date of issuance of the Report and its accuracy is limited to the time period and

circumstances in which it was collected, processed, made or issued; must be read as a whole and sections thereof should not be read out of such context; was prepared for the specific purposes described in the Report and the Agreement; and in the case of subsurface, environmental or geotechnical conditions, may be based on limited testing and on the

assumption that such conditions are uniform and not variable either geographically or over time. Consultant shall be entitled to rely upon the accuracy and completeness of information that was provided to it and has no obligation to update such information. Consultant accepts no responsibility for any events or circumstances that may have occurred since the date on which the Report was prepared and, in the case of subsurface, environmental or geotechnical conditions, is not responsible for any variability in such conditions, geographically or over time. Consultant agrees that the Report represents its professional judgement as described above and that the Information has been prepared for the specific purpose and use described in the Report and the Agreement, but Consultant makes no other representations, or any guarantees or warranties whatsoever, whether express or implied, with respect to the Report, the Information or any part thereof. Without in any way limiting the generality of the foregoing, any estimates or opinions regarding probable construction costs or construction schedule provided by Consultant represent Consultant’s professional judgement in light of its experience and the knowledge and information available to it at the time of preparation. Since Consultant has no control over market or economic conditions, prices for construction labour, equipment or materials or bidding procedures, Consultant, its directors, officers and employees are not able to, nor do they, make any representations, warranties or guarantees whatsoever, whether express or implied, with respect to such estimates or opinions, or their variance from actual construction costs or schedules, and accept no responsibility for any loss or damage arising therefrom or in any way related thereto. Persons relying on such estimates or opinions do so at their own risk. Except (1) as agreed to in writing by Consultant and Client; (2) as required by-law; or (3) to the extent used by governmental reviewing agencies for the purpose of obtaining permits or approvals, the Report and the Information may be used and relied upon only by Client. Consultant accepts no responsibility, and denies any liability whatsoever, to parties other than Client who may obtain access to the Report or the Information for any injury, loss or damage suffered by such parties arising from their use of, reliance upon, or decisions or actions based on the Report or any of the Information (“improper use of the Report”), except to the extent those parties have obtained the prior written consent of Consultant to use and rely upon the Report and the Information. Any injury, loss or damages arising from improper use of the Report shall be borne by the party making such use.

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RPT-2012-08-29 - Draft Final PDR- 60159482.Docx

Distribution List

# of Hard Copies Soft Copy Required Association / Company Name

5 By ACONEX April 3, 2012

Region of Waterloo

- By ACONEX April 30, 2012

Region of Waterloo

3 By ACONEX August 29, 2012

Region of Waterloo

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QC Review Log

Revision Log

Version Date Prepared by

(Deliverable Lead) QC Reviewer QC Review Date

Project Manager or Assistant PM Sign-off

1 March 16, 2012 Ignatius Ip Pat Coleman March 30, 2012 John Armistead 2 April 23, 2012 Ignatius Ip Ansel Bather April 27, 2012 John Armistead 3 August 27, 2012 Kimberley Thomas Ignatius Ip August 28, 2012 John Armistead

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AECOM Signatures Report Prepared By: Ignatius Ip, P.Eng.

Design Manager

Report Reviewed By: John D. Armistead P.Eng.

Project Manager, Water

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RPT-2012-08-29 - Draft Final PDR- 60159482.Docx ES-1

Executive Summary The existing Kitchener Wastewater Treatment Plant (WWTP) is a conventional secondary treatment facility, which has a rated capacity of 122,745 m3/d, as approved in its current Certificate of Approval (C of A). The plant is comprised of two (2) separate secondary treatment plants served by common headworks and primary clarifier facilities. Plant 1 was constructed in the early 1960s and Plant 2 was constructed in the mid-1970s. Both facilities discharge to a common chlorine contact chamber, where chlorination and de-chlorination occur prior to discharge through an outfall terminating in a submerged dual port diffuser in the Grand River. Two on-site (2) digested sludge storage lagoons were historically used for seasonal storage of digested sludge from the Kitchener WWTP. The liquid sludge has been pumped to an off-site transfer station, the Wastewater Residuals Management Centre (WWRMC) on Maintou Drive, while supernatant has been returned to the plant. The Region has initiated a three (3) phase program of upgrade projects related to the Kitchener WWTP. Phase 1 included the upgrade of the WWRMC to include centrifuges for biosolids dewatering. Since the recent completion of Phase 1, centrate from the WWRMC has been returned for treatment at the Kitchener WWTP. The Phase 2 upgrades, which are currently under construction, will improve the ability of Plant 2 to treat centrate and enhance ammonia removal in the aeration facility. A new UV disinfection and effluent pumping station facility is also being constructed to ensure appropriate levels of disinfection are met and non-acutely toxic effluent is released to the Grand River as well as to prevent the flooding of the plant during high flow events and/or high river levels. The third phase of upgrades will provide reliable and efficient operation in the long term, and address additional Grand River water quality requirements through improved effluent quality. The Phase 3 upgrades will include the decommissioning and demolition of the biosolids storage lagoons, construction of a new secondary treatment plant, replacement/refurbishment of selected process facilities, electrical upgrades, new sludge thickening facilities and the decommissioning and demolition of Plant 1, as well as a number of minor upgrades to address deficiencies throughout the plant. This Preliminary Design Report (PDR) presents details of the Preliminary Design of the Phase 3 upgrades of the Kitchener WWTP and builds on the findings/recommendations of the Site Wide Facility Plan, which defined a program of upgrades for the Kitchener WWTP that can reliably meet performance objectives for an approximate 30 year time frame. The PDR is intended to identify the recommended selection of process treatment alternatives, determine the required sizing of selected equipment/tanks and identify ancillary needs such as architectural, structural, electrical, building mechanical, and instrumentation and control. The PDR also documents the expected time frame and costs for the proposed works. The PDR will form the basis of the detailed design. The PDR represents approximately the 30% design level, although certain aspects (process in particular) have been developed well beyond the 30% level while other aspects (site works in particular), which are dependent on design details, have been developed only to the conceptual level. Due to the magnitude and complexity of this project, the work will be carried out through a number of construction contracts over a period of approximately 10 years. The Phase 3 Upgrades have been grouped into 5 main contracts. The use of multiple contracts gives the Region improved project staging and cash flow control and provides greater opportunity for smaller local contractors to participate in the work. Several of the contracts will be further broken into smaller contracts based on schedule and/or the nature of the works to be undertaken. The 5 main contracts are: Contract 1 – Lagoon Decommissioning and Digested Sludge Transfer Pumping Contract 2 – Energy Centre and Anaerobic Digestion Contract 3 – Headworks, Tertiary Treatment, and Outfall Contract 4 – Plants 3 and 4 Secondary Treatment, Plant 2 return activated sludge/waste activated sludge

(RAS/WAS) pumping, and some Miscellaneous Works

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Contract 5 – New administration building, sludge thickening and remaining miscellaneous works

The major upgrades discussed in this PDR are as follows: Two (2) Parshall flume flow meters will be installed on the new twin influent channels immediately upstream of

the new Headworks Building. Headworks – The existing headworks facility will be demolished and replaced with a new headworks facility and

process equipment. Wastewater will enter through a modified influent channel. Screening – Four (4) perforated plate mechanical screens will remove larger debris and solids from the

wastewater, protecting downstream equipment. Screenings will be sluiced in two (2) channels to two (2) screenings washer/compactors, from which the material will be dropped into disposal bins.

Grit Removal – Two (2) vortex grit separators, equipped with three (3) grit pumps and two (2) grit classifiers

De-Gritted Wastewater Pumping will be used to reduce plant service water demands by providing sufficient flow and pressure to high service water demand processes in the Headworks building

Primary Clarifiers – The four (4) existing primary clarifiers will remain in service. The traveling bridge sludge and scum collection system will be replaced with chain and flight collectors, the existing scum cross-collector will be removed and an actuated scum trough installed in front of the effluent weirs. All of the existing sludge pumps and grinders will be replaced and the piping configuration simplified. Existing scum pumps will also be replaced.

Primary Effluent Flow Splitting Chamber – Primary effluent will be diverted to the new flow splitting chamber constructed adjacent to the west end of the primary clarifiers. Flow will be conveyed to Plants 2, 3 and 4 at a controlled rate via dedicated 900/1050 mm diameter pipes.

Secondary Treatment – Aeration Tanks Plant 1 – The existing Plant 1 aeration tanks will be decommissioned and demolished upon completion of

the Phase 3 secondary treatment upgrades. Interim upgrades have been implemented to improve the capacity and efficiency of these facilities until the Plant 3 and 4 secondary treatment systems are commissioned. Two blowers have been installed in a temporary enclosure and will eventually be moved into the new Blower Building, currently under construction as part of the Plant 2 upgrades, and incorporated into the blower system providing air for the Plants 3 and 4 aeration requirements.

Plant 2 – The Plant 2 aeration tanks will remain in service. Upgrades to these tanks are currently under construction as part of the Phase 2 Upgrades and the tanks will be ready for operation before commissioning of the Plants 3 and 4 secondary treatment systems and decommissioning and demolition of the Plant 1 secondary treatment tanks.

Plant 3 and 4 – Plant 3 and 4 will each have two (2) new 3-pass plug flow aeration tanks with step-feed capability, designed to achieve full nitrification. The design includes a three-stage anoxic selector located at the front end of Pass 1 of each aeration tank. The aerated zones of the aeration tanks will be equipped with grids of fine bubble membrane diffusers to distribute process air supplied by aeration blowers. The design allows for the accommodation of future modifications to increase denitrification and space has been allocated for future aeration tank expansion to accommodate future, more stringent treatment limits.

Secondary Treatment – Secondary Clarifiers Plant 1 – The existing Plant 1 clarifiers will be abandoned and demolished.

Plant 2 – Plant 2 will continue to remain in service to treat an average flow of approximately 40,000 m3/d. The existing secondary clarifier mechanisms will be replaced and a secondary scum collection system will be added. The launder elevations may be raised by approximately 200 mm to provide additional freeboard capacity for the downstream tertiary filtration facility. Secondary scum will be collected in two (2) pre-cast, duplex submersible pumping stations and pumped to the WAS discharge header.

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Plants 3 and 4 – The Plant 3 and 4 secondary clarification systems will each consist of four (4) new circular secondary clarifiers and associated mechanisms. Settled activated sludge will be conveyed to secondary sludge hoppers at the centre of each clarifier using a spiral type sludge scraper. Scum will be skimmed into a secondary scum chamber and subsequently pumped to the discharge of the WAS pumps to be transferred to the primary clarifiers.

Secondary Treatment – RAS/WAS Pumping Plant 1 – The existing sludge pumps will be abandoned and removed. Plant 2 – The existing RAS/WAS screw pumping station and associated equipment will be abandoned

and demolished. A new Plant 2 RAS/WAS pumping station consisting of six (6) RAS pumps and two (2) WAS pumps will be constructed on the site of the existing screw pumping station.

Plants 3 and 4 – Two (2) new Plant 3 and 4 RAS/WAS sludge pump stations will be constructed. Each pumping station will have dedicated RAS sludge pumps from each secondary clarifier with a common standby for every two (2) secondary clarifiers (4 duty, 2 standby in total). Two (2) WAS pumps will be provided in each sludge pump station. The pumping stations will be joined by a pipe service tunnel. The RAS discharge lines of the Plant 3 and 4 pumping stations will be interconnected to allow for some transferring of RAS between the two (2) plants under special operating circumstances. WAS from all three (3) pumping stations is discharged to the WAS holding tanks or the primary clarifiers through separate common discharge lines.

Tertiary Filtration – A new Tertiary Filtration building will be constructed to house disk filters. The preliminary design has been based on the use of the Aqua-Aerobics Aquadisk® disk filter technology, as this is the most common type of disk filter system currently in use in Canada. A pilot study will be conducted to select the preferred equipment to be used in the final design. The preliminary design includes fourteen (14) units, with space to add two (2) additional filter units in the future. The building will include facilities for backwashing the filters and returning the backwash water to the main treatment process.

Outfall – A new outfall comprised of a new 1950 mm diameter concrete effluent pipe (overland and in-river) and 1800 mm diffuser structure will be constructed downstream of the existing outfall pipe to accommodate the design peak flow of 430,000 m3/d. The existing outfall pipe and diffuser structure will be removed from the river.

WAS Thickening – WAS from Plants 2, 3 and 4 will be pumped to new WAS holding tanks in the Thickening Building. Dedicated pumps will pump WAS from the WAS holding tanks to the flocculation tank upstream of the three (3) Rotary Drum Thickeners (RDTs). Primary sludge will be diverted to the Thickening Building and blended with thickened WAS (TWAS); blended sludge (TWAS and primary sludge) will then be pumped to the primary digesters. Flexibility will be provided to maintain separation of the TWAS and primary sludges for optimization of the digestion process.

Anaerobic Digestion The two (2) existing oldest anaerobic digesters (existing Digesters No. 1 and 2) will be abandoned and

demolished. A new digester control building to extend the existing primary digester building to connect with the two (2)

existing primary digesters (Digesters No. 5 and 6) and the secondary digester (Digester No. 3) will be constructed.

Two (2) existing primary digesters will be upgraded through the replacement of the mixing system, and installation of a new heating system with a dedicated sludge recirculation pump and heat exchanger for each digester, and new steel covers.

One (1) of the existing secondary digesters will be upgraded to include a mixing system with floor mounted and surface nozzles fed by the two (2) (1 duty, 1 standby) digester sludge mixing pumps and a new gas membrane holder.

The digester gas handling system will be upgraded. Digester gas will be stored in the secondary digester membrane cover and burned as a source of fuel for the future combined heat and power system (CHP) and as required in the hot water boilers. Excess digester gas will be flared in the new waste gas burners, if required.

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Digested Sludge Handling – New digested sludge transfer pumps, suction and discharge piping, and surge protection control will be provided to pump digested sludge to the new WWRMC upon decommissioning of the existing booster transfer station associated with the sludge storage lagoons.

Other facilities or systems that will be added, upgraded, modified, replaced or decommissioned include: Biosolids Sludge Lagoons Decommissioning – In order to address odour concerns and provide space for the

new Plant 3 and 4 secondary treatment facilities, the existing sludge lagoons will be decommissioned. Other Facilities Decommissioning – Several other facilities at the site will require decommissioning and

demolition including the old Administration/Boiler Building, existing Headworks Building, former abandoned digesters, Plant 1 aeration tanks and secondary clarifiers and associated facilities, and existing Plant 2 RAS/WAS pump station.

Cogeneration System – Accommodations for a future cogeneration system using the digester gas have been included in the design.

Existing Administration Building – Modifications to the existing Administration Building to include a maintenance area, staff offices, a training room, and storage space.

New Administration Building – A new Administration Building will be designed to achieve LEED Silver designation. The ground floor of the building will house the site reception, laboratory, training room, men’s and women’s washroom/change room facilities, offices and the mechanical room. The second floor level will include the control room, SCADA room, meeting room, lunch room, offices, library/archive room, and washroom.

Energy Centre – The new Energy Center will be constructed concurrently with the anaerobic digester system upgrades. The facility is recommended to be the primary point for a 13.8 kV distribution system. The system will include outdoor substation, switchgear, transformers, and two (2) 1750 kW standby diesel standby generators.

The PDR presents a contract staging plan, construction sequencing details and cash flow projection (in 2012 dollars). The estimated total project cost for the recommended facilities is summarized in Table ES-1.

Table ES-1 Estimated Project Cost

Item Description Contract 1 Contract 2 Contract 3 Contract 4 Contract 5 & Misc. Upgrade

Total Project Cost

SUB TOTAL $13.60 M $28.90 M $44.10 M $61.30 M $32.60 M $180.50 M Estimating Allowance $2.72 M $5.78 M $8.82 M $12.26 M $6.52 M $36.10 M Contractor Overhead/Profit $2.45 M $5.20 M $7.94 M $11.03 M $5.87 M $32.49 M Construction Contingency $0.94 M $1.99 M $3.04 M $4.23 M $2.25 M $12.45 M CONSTRUCTION COST TOTAL $19.7 M $41.9 M $63.9 M $88.8 M $47.2 M $261.5 M Engineering1 $2.36 M $5.03 M $7.67 M $10.66 M $5.67 M $31.39 M Region Staff Fee1 $0.39 M $0.84 M $1.28 M $1.78 M $0.94 M $5.23 M PROJECT COST TOTAL $22.5 M $47.7 M $72.8 M $101.3 M $54.0 M $298.3 M Note: 1. Based on Region of Waterloo Wastewater Design Standard 52005 (Region of Waterloo, 2009)

The Region has committed to decommissioning of the sludge lagoons by 2015; this work is currently underway and expected to be completed by the end of 2013. The Region has committed to implementing the effluent quality improvements by 2018. The key process upgrades affecting the effluent quality (secondary treatment Plants 2, 3 and 4) and tertiary treatment have been scheduled for completion by the end of 2017.

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The cash flow has been planned to match the council approved whole sale user rate increases that have been included in the 2011 ten-year Capital program. The Preliminary Design was subject to a Value Engineering (VE) study by a multidiscipline team lead by a VE facilitator. The VE team identified 26 VE Alternatives with performance and/or cost savings potential and 20 design suggestions that are expected to result in performance improvements, constructability enhancements, and/or non-quantifiable cost savings. The final categorization of the VE Alternatives, based on decisions made at the VE Implementation meeting, included 12 alternatives are Recommended (R), 21 alternatives will be considered during detailed design (C) and 14 alternatives are Not Recommended (NR) (two options were included under 2 categories). Some of the items identified as to be determined during detailed design could have a significant impact on the design and these will have to be resolved at the earliest opportunity during detailed design to avoid impacting the schedule and cost.

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Glossary AC Air conditioning ACM Asbestos containing materials AHU Air handling unit AOR Actual oxygen requirement C of A Amended Certificate of Approval CFD Computational fluid dynamics CHP Combined heat and power system DFO Department of Fisheries and Oceans DI Ductile iron DO Dissolved oxygen E. coli Escherichia coli EA Environmental Assessment EACO Environmental Abatement Council of Ontario EFW Energy from Waste EPA Environmental Protection Act EPS Effluent pumping station ESR Class EA Environmental Study Report GRCA Grand River Conservation Authority H2S Hydrogen sulphide HDPE High density polyethylene ID fan Induced draught fan LCP Local control panel LEED Leadership in Energy and Environmental Design mASL Meters above sea level MASW Multi-channel analyses of surface wave mbgs Meters below ground surface MCC Motor control centre MCP Master control panel MGD Million gallons per day MLD Million litres per day MLSS Mixed liquor suspended solids MNR Ministry of Natural Resources MOE Ministry of the Environment MOL Ministry of Labour MTC Ministry of Tourism and Culture NASM Non Agricultural Source Materials NMA Nutrient Management Act NPSH Net positive suction head O&M Operation and maintenance O. Reg Ontario Regulation OBC Ontario building code OCS Odour control system OCWA Ontario Clean Water Agency ODS Ozone Depleting Substances OFC Ontario Fire Code OHSA Occupational Health and Safety Act OMAFRA Ontario Ministry of Agriculture, Food and Rural Affairs

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OU Odour units PAH Polyaromatic hydrocarbons PCB Polychlorinated biphenyls PCN Process control narrative PDM Process design memo PDR Preliminary Design Report PHC Petroleum hydrocarbons PM Particulate matter PTI Post-Tensioning Institute PTTW Permit-To-Take-Water RAS Return activated sludge RDL Reportable detection limit SAR Soil absorption ratio SARA Species At Risk Act SCADA Supervisory control and data acquisition SCS Site condition standards SLS Serviceability limit states SMACNA Sheet Metal and Air Conditioning Contractors National Association SOR Standard oxygen requirement SPL SPL Consultants Limited SPMDD Standard Proctor Maximum Dry Density SRT Solids retention time TDH Total dynamic head The Region Region of Waterloo TM Technical memorandum TP Total phosphorous TWAS Thickened waste activated sludge UFFI Urea formaldehyde foam insulation ULS Ultimate limit states UV Ultra violet VFD Variable frequency drive VOC Volatile organic compounds WAS Waste activated sludge WWRMC Wastewater Residuals Management Centre WWTP Wastewater treatment plant

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Table of Contents Statement of Qualifications and Limitations Letter of Transmittal Distribution List Executive Summary

page

1. Introduction .................................................................................................................................. 1 1.1 Authorization................................................................................................................................... 1 1.2 Background .................................................................................................................................... 1 1.3 Approach ........................................................................................................................................ 2 1.4 Objectives ....................................................................................................................................... 3 1.5 Class Environmental Assessment ................................................................................................... 3 1.6 Scope of Work ................................................................................................................................ 4 1.7 Value Engineering .......................................................................................................................... 5 1.8 Previous Reports ............................................................................................................................ 5

1.8.1 Process Design Memoranda .............................................................................................. 5 1.8.2 Additional Background Data Collection and Assessment Work ........................................... 6

1.8.2.1 Geotechnical Investigation ................................................................................ 6 1.8.2.2 Structural Assessment .................................................................................... 11 1.8.2.3 Designated Substances and Hazardous Building Materials Audit .................... 11 1.8.2.4 Lagoon Subsurface Investigation .................................................................... 13

1.8.3 Underground Utilities Locates ........................................................................................... 19 1.8.4 Hydraulic Transient Analysis ............................................................................................ 19 1.8.5 Site Wide Facility Plan ...................................................................................................... 20

1.9 Site Layout ................................................................................................................................... 21 1.10 Approvals ..................................................................................................................................... 21

2. Existing Facility Assessment .................................................................................................... 23 2.1 Site Details ................................................................................................................................... 23

2.1.1 Environmental Features, Surface Waters and Flood Plain Mapping .................................. 23 2.1.2 Available Space ............................................................................................................... 24 2.1.3 Existing Wastewater Residuals Management Centre ........................................................ 24 2.1.4 Site Constraints ................................................................................................................ 24

2.2 Baseline Treatment Processes...................................................................................................... 25 2.2.1 Preliminary Treatment ...................................................................................................... 25 2.2.2 Primary Treatment............................................................................................................ 26 2.2.3 Secondary Treatment ....................................................................................................... 26 2.2.4 Anaerobic Digestion Facility and Sludge Holding Tanks .................................................... 28 2.2.5 Boiler Building and Associated Facilities ........................................................................... 28 2.2.6 Process Equipment in the Administration Building ............................................................ 29 2.2.7 Chlorination ...................................................................................................................... 29

2.3 Baseline Greenhouse Gas Emissions ........................................................................................... 29 2.4 Existing Certificate of Approval...................................................................................................... 29

2.4.1 Plant Rated Capacity ........................................................................................................ 30 2.4.2 Plant Treatment Objectives and Non-Compliance Limits ................................................... 30

3. Overview ..................................................................................................................................... 31

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4. Design Criteria ........................................................................................................................... 32 4.1 Raw Wastewater Flows................................................................................................................. 32 4.2 Wastewater Characteristics and Loadings ..................................................................................... 32 4.3 Effluent Criteria ............................................................................................................................. 33 4.4 Sludge and Biosolids Generation Rates ........................................................................................ 33

5. Odour Management Plan ........................................................................................................... 34 5.1 Existing Conditions and Information .............................................................................................. 34

5.1.1 General Description .......................................................................................................... 34 5.1.1.1 XCG Study (2007) .......................................................................................... 34 5.1.1.2 CH2M HILL Study (2008) ................................................................................ 35

5.1.2 Preliminary Design Odour Assessment ............................................................................. 36 5.1.3 Quality of Information and Next Steps ............................................................................... 37

5.2 Process Design ............................................................................................................................ 38

6. Evaluation of Upgrade Alternatives .......................................................................................... 39 6.1 Primary Effluent Flow Distribution ................................................................................................. 39

6.1.1 Primary Effluent Distribution Option 1: Proposal Concept .................................................. 39 6.1.2 Primary Effluent Flow Distribution Option 2: Preliminary Design Concept .......................... 41 6.1.3 Comparison of Primary Effluent Distribution Options ......................................................... 41 6.1.4 Option Carried Forward .................................................................................................... 41

6.2 Digester Heating ........................................................................................................................... 42 6.2.1 Digester Heating Option 1: Rehabilitate Existing Boilers ................................................... 42

6.2.1.1 Existing Boiler Description .............................................................................. 42 6.2.1.2 Rehabilitation Requirements ........................................................................... 42 6.2.1.3 Construction Sequencing ................................................................................ 43

6.2.2 Digester Heating Option 2: New Boilers ............................................................................ 43 6.2.3 Comparison of Digester Heater Options............................................................................ 44 6.2.4 Option Carried Forward .................................................................................................... 44

6.3 Digester Operation ........................................................................................................................ 44 6.3.1 Background ...................................................................................................................... 44 6.3.2 Option Carried Forward .................................................................................................... 45

6.4 Digestion Configuration ................................................................................................................. 45 6.4.1 Digester Configuration Limitations and Deficiencies .......................................................... 45 6.4.2 Digester Configuration Option 1: No Standby Primary Digester Mixing Pump .................... 45 6.4.3 Digester Configuration Option 2: Large Building Extension with Basement ........................ 46 6.4.4 Digester Configuration Option 3: Alternative Mixing System .............................................. 46 6.4.5 Comparison of Digester Configuration Options ................................................................. 46 6.4.6 Option Carried Forward .................................................................................................... 47

6.5 Plant 2 RAS/WAS Pumping Station............................................................................................... 47 6.5.1 Plant 2 RAS/WAS Pumping Station Original Concept ....................................................... 47 6.5.2 Plant 2 RAS/WAS Pumping Station Option 1 .................................................................... 48 6.5.3 Plant 2 RAS/WAS Pumping Station Option 2 .................................................................... 49 6.5.4 Option Carried Forward .................................................................................................... 50

7. Lagoon Decommissioning (Contract 1a) .................................................................................. 51 7.1 Key Considerations ....................................................................................................................... 51

7.1.1 Regulatory Compliance Overview ..................................................................................... 52 7.1.1.1 Incineration ..................................................................................................... 52 7.1.1.2 Land Application ............................................................................................. 52 7.1.1.3 Landfilling ....................................................................................................... 53

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7.1.1.4 Soil and Groundwater Quality ......................................................................... 53 7.2 Lagoon Decommissioning Options ................................................................................................ 54

7.2.1 Processing Options .......................................................................................................... 54 7.2.2 Disposal Options .............................................................................................................. 56

7.3 Lagoon Decommissioning Design Assumptions ............................................................................ 59 7.4 Lagoon Decommissioning Plan ..................................................................................................... 60

7.4.1.1 Planning and Site Preparation ......................................................................... 60 7.4.2 Chronology of Activities .................................................................................................... 61

7.4.2.1 Lagoon 1 ........................................................................................................ 61 7.4.2.2 Lagoon 2 ........................................................................................................ 61

7.4.3 Infrastructure .................................................................................................................... 62 7.4.4 Site Laydown Area and Temporary Storage...................................................................... 62 7.4.5 Dewatering ....................................................................................................................... 63

7.4.5.1 Supernatant .................................................................................................... 63 7.4.5.2 Lagoon 1 ........................................................................................................ 63 7.4.5.3 Lagoon 2 ........................................................................................................ 63

7.4.6 Dredging/Dewatering of Biosolids ..................................................................................... 64 7.4.6.1 Lagoon 1 ........................................................................................................ 64 7.4.6.2 Lagoon 2 ........................................................................................................ 64

7.4.7 Excavation ....................................................................................................................... 64 7.4.7.1 Biosolids/Soil Cover/Clay Liner/Berm Material ................................................. 65 7.4.7.2 Materials Beneath the Lagoons ....................................................................... 66 7.4.7.3 Yard Piping and Booster Pump Station ........................................................... 66

7.4.8 Water Management During Excavation ............................................................................. 66 7.4.9 Erosion Control During Excavation ................................................................................... 66 7.4.10 Noise Control ................................................................................................................... 67 7.4.11 Transportation and Disposal of Excavated Material........................................................... 67 7.4.12 Decontamination/Wash Pads............................................................................................ 67 7.4.13 Backfilling and Re-grading ................................................................................................ 67

7.5 Site Survey ................................................................................................................................... 68 7.6 Odour Control ............................................................................................................................... 68

7.6.1.1 General Description ........................................................................................ 68 7.6.1.2 Sampling of Excavated Materials .................................................................... 68 7.6.1.3 Real Time Monitoring ...................................................................................... 69

7.7 Construction ................................................................................................................................. 69 7.7.1 Constructability................................................................................................................. 69

7.7.1.1 Data Gap and Field Sampling Plan ................................................................. 69 7.7.1.2 Environmental Protection Plan ........................................................................ 69 7.7.1.3 Decommissioning Schedule ............................................................................ 69

8. Digested Sludge Transfer Pumping (Contract 1b) ................................................................... 70 8.1 Existing Digested Sludge Transfer Pumping System ..................................................................... 70 8.2 General Description ...................................................................................................................... 70 8.3 Process Design ............................................................................................................................ 71

8.3.1 Design Criteria ................................................................................................................. 71 8.3.2 Preliminary Design Specifications ..................................................................................... 71 8.3.3 Operating Philosophy, Instrumentation and Controls ......................................................... 72

8.3.3.1 Digested Sludge Transfer Pumps .................................................................... 72 8.3.3.2 Surge Relief System ....................................................................................... 73

8.4 Digested Sludge Transfer Piping ................................................................................................... 73 8.4.1 Design Alternatives .......................................................................................................... 73

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8.4.1.1 Option 1: Keep All Existing Suction Piping As Is .............................................. 74 8.4.1.2 Option 2: Replace Yard Piping and Keep Digester Complex and Digested

Sludge Transfer Pump Station Piping As Is ..................................................... 74 8.4.1.3 Option 3: Replace Yard and Digester Complex Piping and Flowmeter in

the Pump Room .............................................................................................. 74 8.4.2 Design Basis .................................................................................................................... 75

8.5 Architectural and Structural Design ............................................................................................... 75 8.6 Building Mechanical Design .......................................................................................................... 75

8.6.1 Heating, Ventilation and Air Conditioning .......................................................................... 75 8.6.1.1 Existing Ventilation and Heating Systems ....................................................... 75 8.6.1.2 Upgrades to Ventilation and Heating Systems ................................................. 76 8.6.1.3 HVAC Controls ............................................................................................... 76

8.6.2 Plumbing and Drainage .................................................................................................... 76 8.6.2.1 Potable Water ................................................................................................. 76 8.6.2.2 Plant Service Water ........................................................................................ 76 8.6.2.3 Roof Drain System .......................................................................................... 76 8.6.2.4 Floor Drain System ......................................................................................... 76 8.6.2.5 Sanitary Sumps .............................................................................................. 76

8.6.3 Emergency Safety Equipment .......................................................................................... 76 8.7 Electrical Design ........................................................................................................................... 77 8.8 Instrumentation and Control Design .............................................................................................. 77 8.9 Construction Sequencing, Tie-Ins, and Demolition ........................................................................ 77

9. Anaerobic Digestion (Contract 2b) ........................................................................................... 78 9.1 Existing Anaerobic Digestion System ............................................................................................ 78 9.2 General Description ...................................................................................................................... 79 9.3 Process Design ............................................................................................................................ 81

9.3.1 Anaerobic Digesters ......................................................................................................... 81 9.3.1.1 General Description ........................................................................................ 81 9.3.1.2 Design Criteria ................................................................................................ 82 9.3.1.3 Preliminary Design Specifications ................................................................... 82 9.3.1.4 Operating Philosophy, Instrumentation and Controls ....................................... 82

9.3.2 Digester Mixing ................................................................................................................ 83 9.3.2.1 General Description ........................................................................................ 83 9.3.2.2 Design Criteria ................................................................................................ 83 9.3.2.3 Preliminary Design Specifications ................................................................... 83 9.3.2.4 Operating Philosophy, Instrumentation and Controls ....................................... 84

9.3.3 Digester Heating and Recirculation ................................................................................... 84 9.3.3.1 General Description ........................................................................................ 84 9.3.3.2 Design Criteria ................................................................................................ 84 9.3.3.3 Preliminary Design Specifications ................................................................... 84 9.3.3.4 Operating Philosophy, Instrumentation and Controls ....................................... 84

9.3.4 Digester Gas Handling System ......................................................................................... 85 9.3.4.1 General Description ........................................................................................ 85 9.3.4.2 Design Criteria ................................................................................................ 85 9.3.4.3 Preliminary Design Specifications ................................................................... 85 9.3.4.4 Operating Philosophy, Instrumentation and Controls ....................................... 85

9.4 Architectural and Structural Design ............................................................................................... 86 9.5 Building Mechanical Design .......................................................................................................... 86

9.5.1 Heating, Ventilation and Air Conditioning .......................................................................... 86 9.5.1.1 Heating System .............................................................................................. 87 9.5.1.2 Ventilation Systems ........................................................................................ 87

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9.5.1.3 Air Conditioning .............................................................................................. 88 9.5.2 Plumbing and Drainage .................................................................................................... 88

9.5.2.1 Potable Water ................................................................................................. 88 9.5.2.2 Plant Service Water ........................................................................................ 88 9.5.2.3 Roof Drain System .......................................................................................... 88 9.5.2.4 Floor Drain System ......................................................................................... 88

9.5.3 Emergency Safety Equipment .......................................................................................... 88 9.6 Electrical Design ........................................................................................................................... 88 9.7 Instrumentation and Control Design .............................................................................................. 89 9.8 Construction Sequencing, Tie-Ins, and Demolition ........................................................................ 89

10. Headworks (Contract 3a) ........................................................................................................... 90 10.1 Existing Headworks Facility........................................................................................................... 90 10.2 General Description ...................................................................................................................... 90 10.3 Process Design ............................................................................................................................ 92

10.3.1 Raw Sewage Flow Monitoring .......................................................................................... 92 10.3.1.1 General Description ........................................................................................ 92 10.3.1.2 Design Criteria ................................................................................................ 92 10.3.1.3 Preliminary Design Specifications ................................................................... 92 10.3.1.4 Operating Philosophy, Instrumentation and Controls ....................................... 92

10.3.2 Screening ......................................................................................................................... 92 10.3.2.1 General Description ........................................................................................ 92 10.3.2.2 Design Criteria ................................................................................................ 93 10.3.2.3 Preliminary Design Specifications ................................................................... 93 10.3.2.4 Operating Philosophy, Instrumentation and Controls ....................................... 94

10.3.3 Grit Removal .................................................................................................................... 95 10.3.3.1 General Description ........................................................................................ 95 10.3.3.2 Design Criteria ................................................................................................ 95 10.3.3.3 Preliminary Design Specifications ................................................................... 96 10.3.3.4 Operating Philosophy, Instrumentation and Controls ....................................... 96

10.3.4 De-Gritted Wastewater Pumping ...................................................................................... 97 10.3.4.1 General Description ........................................................................................ 97 10.3.4.2 Design Criteria ................................................................................................ 97 10.3.4.3 Preliminary Design Specifications ................................................................... 98 10.3.4.4 Operating Philosophy, Instrumentation and Controls ....................................... 98

10.3.5 Phosphorus Removal Chemical System ........................................................................... 98 10.3.5.1 General Description ........................................................................................ 98 10.3.5.2 Design Criteria .............................................................................................. 100 10.3.5.3 Preliminary Design Specifications ................................................................. 100 10.3.5.4 Operating Philosophy, Instrumentation and Controls ..................................... 100

10.3.6 Channel Aeration ........................................................................................................... 101 10.3.6.1 General Description ...................................................................................... 101

10.3.7 Building Sump ................................................................................................................ 101 10.3.7.1 General Description ...................................................................................... 101

10.4 Odour Control Design ................................................................................................................. 102 10.4.1.1 General Description ...................................................................................... 102 10.4.1.2 Design Criteria .............................................................................................. 103 10.4.1.3 Preliminary Design Specifications ................................................................. 103 10.4.1.4 Operating Philosophy, Instrumentation and Controls ..................................... 105

10.5 Architectural and Structural Design ............................................................................................. 105 10.6 Building Mechanical Design ........................................................................................................ 106

10.6.1 Heating, Ventilation and Air Conditioning ........................................................................ 106

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10.6.1.1 Heating Systems........................................................................................... 107 10.6.1.2 Ventilation Systems ...................................................................................... 107 10.6.1.3 Air Conditioning ............................................................................................ 107

10.6.2 Plumbing and Drainage .................................................................................................. 107 10.6.2.1 Potable Water ............................................................................................... 107 10.6.2.2 Plant Service Water ...................................................................................... 107 10.6.2.3 Roof Drain System ........................................................................................ 108 10.6.2.4 Floor Drain System ....................................................................................... 108

10.6.3 Emergency Safety Equipment ........................................................................................ 108 10.7 Electrical Design ......................................................................................................................... 108 10.8 Instrumentation and Control Design ............................................................................................ 108 10.9 Construction Sequencing, Tie-Ins, and Demolition ...................................................................... 108

11. Tertiary Filtration (Contract 3b)............................................................................................... 109 11.1 General Description .................................................................................................................... 109 11.2 Process Design .......................................................................................................................... 110

11.2.1 Disk Filters ..................................................................................................................... 110 11.2.1.1 General Description ...................................................................................... 110 11.2.1.2 Design Criteria .............................................................................................. 113 11.2.1.3 Preliminary Design Specification ................................................................... 113 11.2.1.4 Operating Philosophy Instrumentation and Controls ...................................... 113

11.2.2 Backwashing .................................................................................................................. 114 11.2.2.1 General Description ...................................................................................... 114 11.2.2.2 Design Criteria .............................................................................................. 114 11.2.2.3 Preliminary Design Specification ................................................................... 114 11.2.2.4 Operating Philosophy Instrumentation and Controls ...................................... 115

11.2.3 Tertiary Bypass .............................................................................................................. 116 11.2.3.1 General Description ...................................................................................... 116 11.2.3.2 Design Criteria .............................................................................................. 116 11.2.3.3 Preliminary Design Specification ................................................................... 116 11.2.3.4 Operating Philosophy Instrumentation and Controls ...................................... 117

11.2.4 Miscellaneous Process Systems..................................................................................... 117 11.2.4.1 Channel Aeration .......................................................................................... 117 11.2.4.2 Process Sump System .................................................................................. 117

11.3 Equipment Procurement ............................................................................................................. 118 11.4 Architectural and Structural Design ............................................................................................. 118 11.5 Building Mechanical Design ........................................................................................................ 118

11.5.1 Heating, Ventilation and Air Conditioning ........................................................................ 118 11.5.1.1 Heating Systems........................................................................................... 119 11.5.1.2 Ventilation Systems ...................................................................................... 119 11.5.1.3 Air Conditioning ............................................................................................ 119

11.5.2 Plumbing and Drainage .................................................................................................. 119 11.5.2.1 Potable Water ............................................................................................... 119 11.5.2.2 Plant Service Water ...................................................................................... 119 11.5.2.3 Roof Drain System ........................................................................................ 119 11.5.2.4 Floor Drain System ....................................................................................... 119 11.5.2.5 Sanitary Sumps ............................................................................................ 120


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12. Outfall (Contract 3b) ................................................................................................................ 121 12.1 General Description .................................................................................................................... 121 12.2 Existing Outfall ............................................................................................................................ 121 12.3 Design Criteria ............................................................................................................................ 122 12.4 Construction Sequencing, Tie-Ins, and Demolition ...................................................................... 123

12.4.1 Environmental Considerations ........................................................................................ 123

13. Secondary Treatment (Contract 4) .......................................................................................... 124 13.1 General Description .................................................................................................................... 124 13.2 Process Design .......................................................................................................................... 125

13.2.1 Primary Effluent Flow Splitting Chamber ......................................................................... 125 13.2.1.1 General Description ...................................................................................... 125 13.2.1.2 Design Criteria .............................................................................................. 126 13.2.1.3 Preliminary Design Specifications ................................................................. 126 13.2.1.4 Operating Philosophy Instrumentation and Controls ...................................... 126

13.2.2 Plant 3 and 4 Aeration Tanks.......................................................................................... 126 13.2.2.1 General Description ...................................................................................... 126 13.2.2.2 Design Criteria .............................................................................................. 127 13.2.2.3 Preliminary Design Specifications ................................................................. 128 13.2.2.4 Operating Philosophy Instrumentation and Controls ...................................... 128

13.2.3 Plant 3 and 4 Process Air System................................................................................... 130 13.2.3.1 General Description ...................................................................................... 130 13.2.3.2 Design Criteria .............................................................................................. 131 13.2.3.3 Preliminary Design Specifications ................................................................. 132 13.2.3.4 Operating Philosophy Instrumentation and Controls ...................................... 133

13.2.4 Plant 3 and 4 Aeration Tank Unwatering System ............................................................ 134 13.2.4.1 General Description ...................................................................................... 134 13.2.4.2 Design Criteria .............................................................................................. 134 13.2.4.3 Preliminary Design Specification ................................................................... 134 13.2.4.4 Operating Philosophy Instrumentation and Controls ...................................... 134

13.2.5 Plant 3 and 4 Secondary Clarifiers .................................................................................. 135 13.2.5.1 General Description ...................................................................................... 135 13.2.5.2 Design Criteria .............................................................................................. 135 13.2.5.3 Preliminary Design Specification ................................................................... 136 13.2.5.4 Operating Philosophy Instrumentation and Controls ...................................... 136

13.2.6 Plant 3 and 4 Secondary Clarifier Unwatering System .................................................... 137 13.2.6.1 General Description ...................................................................................... 137 13.2.6.2 Design Criteria .............................................................................................. 137 13.2.6.3 Preliminary Design Specification ................................................................... 137 13.2.6.4 Operating Philosophy Instrumentation and Controls ...................................... 137

13.2.7 Plant 3 and 4 Secondary Clarifier Scum Pumping System .............................................. 137 13.2.7.1 General Description ...................................................................................... 137 13.2.7.2 Design Criteria .............................................................................................. 137 13.2.7.3 Preliminary Design Specification ................................................................... 138 13.2.7.4 Operating Philosophy Instrumentation and Controls ...................................... 138

13.2.8 RAS/WAS Pumping ........................................................................................................ 138 13.2.8.1 General Description ...................................................................................... 138 13.2.8.2 Plant 2 Existing Facilities .............................................................................. 140 13.2.8.3 Design Criteria .............................................................................................. 140 13.2.8.4 Preliminary Design Specification ................................................................... 141 13.2.8.5 Operating Philosophy Instrumentation and Controls ...................................... 141

13.3 Architectural and Structural Design ............................................................................................. 142

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13.3.1 Plant 3 and 4 Aeration Tanks and Secondary Clarifiers................................................... 142 13.3.2 Plant 2, 3 and 4 RAS/WAS Pumping Stations ................................................................. 142

13.4 Building Mechanical Design ........................................................................................................ 143 13.4.1 Heating, Ventilation and Air Conditioning ........................................................................ 143

13.4.1.1 Heating Systems........................................................................................... 143 13.4.1.2 Ventilation..................................................................................................... 143 13.4.1.3 Air Conditioning ............................................................................................ 144



14. Administration Building (Contract 5a) .................................................................................... 146 14.1 General Description .................................................................................................................... 146 14.2 Architectural Design .................................................................................................................... 146 14.3 Existing Administration Building Description ................................................................................ 146 14.4 LEED Concepts .......................................................................................................................... 147 14.5 Building Mechanical Design ........................................................................................................ 147

14.5.1 Heating, Ventilation and Air Conditioning ........................................................................ 147 14.5.2 Plumbing and Drainage .................................................................................................. 147

14.5.2.1 Potable Water ............................................................................................... 147 14.5.2.2 Plant Service Water ...................................................................................... 148 14.5.2.3 Roof Drain System ........................................................................................ 148 14.5.2.4 Floor Drain System ....................................................................................... 148 14.5.2.5 Sanitary System............................................................................................ 148

14.5.3 Fire Protection ................................................................................................................ 148

15. WAS Thickening (Contract 5b) ................................................................................................ 149 15.1 General Description .................................................................................................................... 149 15.2 Process Design .......................................................................................................................... 151

15.2.1 WAS Holding Tanks and Pumps ..................................................................................... 151 15.2.1.1 General Description ...................................................................................... 151 15.2.1.2 Design Criteria .............................................................................................. 151 15.2.1.3 Preliminary Design Specification ................................................................... 151 15.2.1.4 Operating Philosophy, Instrumentation and Control ....................................... 152

15.2.2 Rotary Drum Thickeners ................................................................................................. 152 15.2.2.1 General Description ...................................................................................... 152 15.2.2.2 Design Criteria .............................................................................................. 152 15.2.2.3 Preliminary Design Specification ................................................................... 153 15.2.2.4 Operating Philosophy, Instrumentation and Control ....................................... 153

15.2.3 Thickening Filtrate Tank and Pumps ............................................................................... 153 15.2.3.1 General Description ...................................................................................... 153 15.2.3.2 Design Criteria .............................................................................................. 153 15.2.3.3 Preliminary Design Specification ................................................................... 154 15.2.3.4 Operating Philosophy, Instrumentation and Control ....................................... 154

15.2.4 Thickened Sludge Holding Tanks and Pumps ................................................................. 154

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15.2.4.1 General Description ...................................................................................... 154 15.2.4.2 Design Criteria .............................................................................................. 155 15.2.4.3 Preliminary Design Specification ................................................................... 155 15.2.4.4 Operating Philosophy, Instrumentation and Control ....................................... 155

15.2.5 Polymer System ............................................................................................................. 156 15.2.5.1 General Description ...................................................................................... 156 15.2.5.2 Design Criteria .............................................................................................. 156 15.2.5.3 Preliminary Design Specification ................................................................... 156 15.2.5.4 Operating Philosophy, Instrumentation and Control ....................................... 157

15.2.6 Hoisting System ............................................................................................................. 158 15.2.7 Odour Control ................................................................................................................ 158

15.2.7.1 General Description ...................................................................................... 158 15.2.7.2 Design Criteria .............................................................................................. 158 15.2.7.3 Preliminary Design Specifications ................................................................. 159 15.2.7.4 Operating Philosophy, Instrumentation and Controls ..................................... 160

15.3 Architectural and Structural Design ............................................................................................. 161 15.4 Building Mechanical Design ........................................................................................................ 162

15.4.1 Heating, Ventilation and Air Conditioning ........................................................................ 162 15.4.1.1 Heating Systems........................................................................................... 162 15.4.1.2 Ventilation Systems ...................................................................................... 162 15.4.1.3 Air Conditioning ............................................................................................ 163



16. Miscellaneous Improvements to Existing Facilities .............................................................. 165 16.1 General Description .................................................................................................................... 165 16.2 Primary Clarifier Upgrades .......................................................................................................... 165

16.2.1 Existing Primary Clarifier Facilities .................................................................................. 165 16.2.2 General Description ........................................................................................................ 165 16.2.3 Process Design .............................................................................................................. 166

16.2.3.1 Primary Sludge Collection Equipment ........................................................... 166 16.2.3.2 Raw Sludge Pumping ................................................................................... 167 16.2.3.3 Scum Removal ............................................................................................. 168

16.2.4 Architectural and Structural Design ................................................................................. 169 16.2.5 Building Mechanical Design ............................................................................................ 170

16.2.5.1 Heating, Ventilation and Air Conditioning ...................................................... 170 16.2.5.2 Plumbing and Drainage................................................................................. 171

16.2.6 Electrical Design ............................................................................................................ 171 16.2.7 Instrumentation and Control Design ................................................................................ 171 16.2.8 Construction Sequencing, Tie-Ins and Demolition ........................................................... 171

16.3 Plant 2 Secondary Clarifier Upgrades ......................................................................................... 171 16.3.1 Existing Plant 2 Secondary Clarifiers .............................................................................. 171 16.3.2 General Description ........................................................................................................ 171 16.3.3 Process Design .............................................................................................................. 172

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16.3.3.1 Secondary Clarifier Mechanisms ................................................................... 172 16.3.3.2 Secondary Scum Pumping ............................................................................ 172

16.3.4 Architectural and Structural Design ................................................................................. 173 16.3.5 Building Mechanical Design ............................................................................................ 173 16.3.6 Electrical Design ............................................................................................................ 174 16.3.7 Instrumentation and Control Design ................................................................................ 174

16.4 Service Water System ................................................................................................................ 174 16.5 Plant 1 Decommissioning ............................................................................................................ 174

17. Electrical Design and Energy Centre (Contract 2a) ............................................................... 176 17.1 Existing Electrical Distribution System ......................................................................................... 176

17.1.1 General .......................................................................................................................... 176 17.1.2 13.8 kV Primary Power Distribution ................................................................................ 176 17.1.3 Main Outdoor Substation ................................................................................................ 176 17.1.4 Standby Emergency Power ............................................................................................ 177

17.2 General Power Distribution ......................................................................................................... 178 17.3 Interim Distribution System Upgrades-By AECOM ...................................................................... 178

17.3.1.1 Interim Aeration Tank N0-1 ........................................................................... 178 17.4 Distribution System Upgrades (Phase 2 Upgrades) ..................................................................... 178

17.4.1 New 13.8kV Primary Outdoor Switchgear ....................................................................... 178 17.4.2 UV Disinfection And Effluent Pumping Upgrades ............................................................ 179 17.4.3 Plant 2 Blower Building Upgrades................................................................................... 179

17.5 Distribution System Upgrades As Part of Preliminary Design....................................................... 179 17.5.1 General .......................................................................................................................... 179 17.5.2 Contract 1b – Digested Sludge Transfer Pumping .......................................................... 181 17.5.3 Contract 2a – Energy Center .......................................................................................... 181 17.5.4 Contract 2b – Anaerobic Digestion ................................................................................. 182 17.5.5 Contract 3a – Headworks Building .................................................................................. 182 17.5.6 Contract 3b – Tertiary Filtration Building ......................................................................... 182 17.5.7 Contract 4 – Plant 2 Blower Building .............................................................................. 182 17.5.8 Contract 4 – RAS/WAS Pumping Stations ...................................................................... 182 17.5.9 Contract 5a – New Administration Building ..................................................................... 182 17.5.10 Contract 5b – WAS Thickening ....................................................................................... 182

17.6 Codes and Standards ................................................................................................................. 182 17.7 Demand Summary ...................................................................................................................... 183

17.7.1 Connected and Peak Loads ........................................................................................... 183 17.7.2 Emergency Power Design Loads .................................................................................... 183

17.8 Standby Power ........................................................................................................................... 184 17.9 Cogeneration Facility .................................................................................................................. 184 17.10 Construction Contract Considerations ......................................................................................... 185

17.10.1 Contract 1b – Digested Sludge Transfer Pumping .......................................................... 185 17.10.2 Contract 2b – Anaerobic Digestion ................................................................................. 185 17.10.3 Contract 2a – Energy Center .......................................................................................... 185 17.10.4 Contract 3a – Headworks Building .................................................................................. 186 17.10.5 Contract 4 – Plant 2 Blower Building ............................................................................... 186 17.10.6 Contract 4 – Plant 3 and 4 RAS/WAS Pumping Station and Secondary Clarifiers............ 186 17.10.7 Contract 4 – Plant 2 RAS/WAS Pumping Station ............................................................ 186 17.10.8 Contract 5b – WAS Thickening ....................................................................................... 186

17.11 Lighting Systems ........................................................................................................................ 187

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18. Common Elements................................................................................................................... 188 18.1 Hydraulics ................................................................................................................................... 188

18.1.1 Hydraulic Profile ............................................................................................................. 188 18.1.2 Tertiary Filtration System Hydraulics............................................................................... 188

18.2 Civil/Site Design.......................................................................................................................... 189 18.2.1 Overall Layout ................................................................................................................ 189 18.2.2 Erosion Control .............................................................................................................. 189 18.2.3 Roads and Access ......................................................................................................... 189 18.2.4 Flood Plain Management and Mitigation ......................................................................... 189 18.2.5 Stormwater Management ............................................................................................... 190

18.3 Structural and Architectural Design ............................................................................................. 190 18.3.1 Codes and Standards ..................................................................................................... 190 18.3.2 Preliminary Ontario Building Code Review ...................................................................... 191 18.3.3 LEED Design Features ................................................................................................... 192 18.3.4 Architectural Theme ....................................................................................................... 192

18.4 Structural and Geotechnical Aspects ........................................................................................... 192 18.4.1 Foundation Considerations ............................................................................................. 192

18.4.1.1 Soil Conditions .............................................................................................. 192 18.4.1.2 Design and Construction Considerations ....................................................... 193

18.4.2 Design Loads ................................................................................................................. 194 18.4.3 Structural Materials ........................................................................................................ 196

18.5 Building Mechanical Design ........................................................................................................ 196 18.5.1 Design Criteria ............................................................................................................... 196

18.5.1.1 Codes and Standards ................................................................................... 196 18.5.1.2 Outdoor Design Criteria ................................................................................ 197 18.5.1.3 Indoor Design Criteria ................................................................................... 197

18.5.2 Energy Code Compliance and Building Insulation ........................................................... 197 18.5.3 Heating, Ventilation and Air Conditioning ........................................................................ 197

18.5.3.1 Ventilation Systems ...................................................................................... 197 18.5.3.2 Ventilation Rates........................................................................................... 198 18.5.3.3 Redundancy ................................................................................................. 198 18.5.3.4 Heat Relief System ....................................................................................... 198 18.5.3.5 Cooling System ............................................................................................ 198 18.5.3.6 Outdoor Air Filtration Criteria ......................................................................... 198 18.5.3.7 Space Pressurization Control Criteria ............................................................ 198 18.5.3.8 Ductwork Criteria .......................................................................................... 199 18.5.3.9 Noise Criteria ................................................................................................ 199 18.5.3.10 Humidity Control Criteria ............................................................................... 199 18.5.3.11 Heating Systems........................................................................................... 199 18.5.3.12 HVAC Controls ............................................................................................. 200 18.5.3.13 Power Supply ............................................................................................... 200

18.5.4 Plumbing and Drainage .................................................................................................. 201 18.5.4.1 Plumbing System Concepts .......................................................................... 201 18.5.4.2 Insulated Plumbing Piping ............................................................................. 201 18.5.4.3 Emergency Safety Equipment ....................................................................... 201 18.5.4.4 Cross-Connection Control ............................................................................. 201 18.5.4.5 Equipment .................................................................................................... 202

18.5.5 Fire Protection ................................................................................................................ 202 18.5.6 Energy-Conserving Enhancements ................................................................................ 202

18.6 Instrumentation and Control Design ............................................................................................ 202 18.6.1 General Description ........................................................................................................ 202

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18.6.2 Equipment Tagging ........................................................................................................ 203 18.6.3 Process Flow Drawings and Piping and Instrumentation Drawings .................................. 203 18.6.4 Process Control Narratives ............................................................................................. 203 18.6.5 Equipment Control Modes .............................................................................................. 203

18.6.5.1 LOCAL/MANUAL .......................................................................................... 203 18.6.5.2 REMOTE/AUTO ........................................................................................... 204 18.6.5.3 REMOTE/MANUAL....................................................................................... 204

18.6.6 Interlocks and Resetting ................................................................................................. 204 18.6.6.1 Interlocks ...................................................................................................... 204 18.6.6.2 Resetting ...................................................................................................... 204

18.6.7 SCADA System Hardware .............................................................................................. 204 18.6.7.1 Field Equipment and Instrumentation ............................................................ 204 18.6.7.2 Controllers and Controller Panels .................................................................. 205

18.6.8 Network Architecture ...................................................................................................... 206 18.6.9 SCADA System Software ............................................................................................... 207 18.6.10 Constructability Considerations for Integration with Existing System ............................... 207 18.6.11 Network Architecture Drawing ........................................................................................ 207

18.7 Energy Management Plan ........................................................................................................... 207 18.7.1 Purpose ......................................................................................................................... 207 18.7.2 Requirements ................................................................................................................. 207 18.7.3 NFPA 820 ...................................................................................................................... 208

18.7.3.1 Classified areas ............................................................................................ 208 18.7.3.2 Unclassified areas ........................................................................................ 208

18.7.4 Ontario Building Code (2006) ......................................................................................... 208 18.7.5 Building Envelope .......................................................................................................... 209 18.7.6 HVAC ............................................................................................................................. 209

18.7.6.1 General ........................................................................................................ 209 18.7.6.2 Kitchener WWTP buildings............................................................................ 210 18.7.6.3 Hydronic Heating System .............................................................................. 211 18.7.6.4 Energy Savings Attributable to Energy Reduction Measures (ERMs)

Applied to Ventilation .................................................................................... 211 18.7.7 Controls ......................................................................................................................... 212 18.7.8 General Electrical ........................................................................................................... 212

18.7.8.1 Distribution Voltage ....................................................................................... 212 18.7.8.2 Voltage Levels .............................................................................................. 212 18.7.8.3 Power Factor Correction Capacitors .............................................................. 213 18.7.8.4 Transformers ................................................................................................ 213 18.7.8.5 Lighting Systems .......................................................................................... 213 18.7.8.6 Energy Efficient Motors ................................................................................. 213 18.7.8.7 VFDs ............................................................................................................ 213 18.7.8.8 Power Monitoring .......................................................................................... 214 18.7.8.9 Co-Generation .............................................................................................. 214

18.7.9 LEED Standard and Sustainable Design......................................................................... 214 18.7.9.1 Reducing Heat Island Effects ........................................................................ 214 18.7.9.2 Light Pollution ............................................................................................... 215 18.7.9.3 Optimizing Energy Performance .................................................................... 215 18.7.9.4 Daylighting .................................................................................................... 215 18.7.9.5 On-Site Renewable Energy ........................................................................... 216 18.7.9.6 Other Sustainable Design Features............................................................... 216

19. Construction............................................................................................................................. 217 19.1 Construction Sequencing ............................................................................................................ 217

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19.2 Construction Staging and Schedule ............................................................................................ 220 19.2.1 Construction Stage 1 (from 12/2012 to10/2013) .............................................................. 220 19.2.2 Construction Stage 2 (from 10/2013 to 4/2015) ............................................................... 221 19.2.3 Construction Stage 3 (from 4/2015 to 7/2015) ................................................................. 221 19.2.4 Construction Stage 4 (from 7/2015 to 9/2015) ................................................................. 222 19.2.5 Construction Stage 5 (from 9/2015 to 12/2015) ............................................................... 222 19.2.6 Construction Stage 6 (from 12/2015 to 10/2017) ............................................................. 222 19.2.7 Construction Stage 7 (from 10/2017 to 6/2018) ............................................................... 222 19.2.8 Construction Stage 8 (from 6/2018 to 7/2020) ................................................................. 222

19.3 Process Shutdowns .................................................................................................................... 222 19.4 Contract specific Tie-Ins.............................................................................................................. 223

19.4.1 Contract 1b – Digested Sludge Transfer Pumping .......................................................... 224 19.4.2 Contract 2a – Energy Centre .......................................................................................... 224

19.4.2.1 Electrical Construction Sequencing ............................................................... 224 19.4.3 Contract 2b – Anaerobic Digestion ................................................................................. 225 19.4.4 Odour Control ................................................................................................................ 226 19.4.5 Contract 3a – Headworks Building .................................................................................. 226 19.4.6 Contract 3a – Tertiary Treatment .................................................................................... 227 19.4.7 Contract 3a – Outfall ...................................................................................................... 227 19.4.8 Contract 4 – Secondary Treatment ................................................................................. 228

19.4.8.1 Primary Effluent Flow Splitting and Primary Effluent Channel Upgrade .......... 228 19.4.8.2 Blower Building ............................................................................................. 229 19.4.8.3 Plant 3 and 4 Aeration Tanks and RAS/WAS Pumping Stations .................... 229 19.4.8.4 Plant 3 and 4 Secondary Clarifiers ................................................................ 229 19.4.8.5 Plant 2 RAS/WAS Pumping Station............................................................... 229

19.4.9 Contract 5b – WAS Thickening ....................................................................................... 230 19.4.10 Miscellaneous Works: Primary Clarifiers ......................................................................... 230

19.5 Hydraulic Considerations ............................................................................................................ 230 19.5.1 Contract 3a – Headworks Discharge............................................................................... 231 19.5.2 Contract 3a – Tertiary Treatment .................................................................................... 231 19.5.3 Contract 4 – Primary Clarifier Effluent Flow Splitting ....................................................... 231

19.6 Demolition .................................................................................................................................. 231 19.6.1 Contract 1b – Digested Sludge Transfer Pumping .......................................................... 231 19.6.2 Contract 4 – Plant 2 RAS/WAS Pumping Station ............................................................ 232 19.6.3 Contract 2a – Energy Center .......................................................................................... 232 19.6.4 Miscellaneous Works – Plant 1 ....................................................................................... 232

19.7 Constructability Review ............................................................................................................... 232 19.8 Design and Construction Plan and Schedule ............................................................................... 232

19.8.1 Equipment Pre-Selection Plan ........................................................................................ 232 19.8.2 Risk Assessment ............................................................................................................ 234

19.8.2.1 Capital and Operating Costs ......................................................................... 235 19.8.2.2 Community Impacts ...................................................................................... 235 19.8.2.3 Schedule ...................................................................................................... 235 19.8.2.4 Risk Register ................................................................................................ 236

20. Project Cost Estimate .............................................................................................................. 237 20.1 Construction Cost Estimate ......................................................................................................... 237

20.1.1 Cost Summary ............................................................................................................... 237 20.1.2 Cost Estimating Basis/Assumptions ................................................................................ 237 20.1.3 Cash Flow Projection ..................................................................................................... 238

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20.2 Operation and Maintenance Cost Estimate ................................................................................. 240

21. Value Engineering .................................................................................................................... 241 List of Figures

Figure 1 Aerial Map of Kitchener WWTP Site and Surrounding Land Uses ......................................................... 1 Figure 2 Kitchener WWTP Flood Plain Mapping ............................................................................................... 23 Figure 3 Process Flow Schematic for Baseline Kitchener WWTP ..................................................................... 25 Figure 4 Primary Effluent Distribution Option 1: Existing Primary Effluent Chamber Modifications ..................... 40 Figure 5 Primary Effluent Distribution Option 1 Schematic ................................................................................ 40 Figure 6 Primary Effluent Distribution Option 2 Schematic ................................................................................ 41 Figure 7 Existing Plant 2 Secondary Clarifier and Return Sludge Screw Pump Layout ...................................... 48 Figure 8 Plan View Schematic of Plant 2 Pumping Station Alternative Layout Option 1 (not to scale)................ 49 Figure 9 Plan View Schematic of Plant 2 Pumping Station Alternative Layout Option 2 (not to scale)................ 50 Figure 10 Simplified Process Flow Schematic of the Digested Sludge Transfer System...................................... 71 Figure 11 Simplified Process Flow Schematic of the Liquid Train of the Anaerobic Digestion System ................. 80 Figure 12 Simplified Process Flow Schematic of the Gas Train of the Anaerobic Digestion System .................... 81 Figure 13 Simplified Process Flow Schematic of the Headworks System............................................................ 91 Figure 14 Flow Schematic for the Kitchener WWTP Headworks OCS .............................................................. 102 Figure 15 Simplified Process Flow Schematic of the Tertiary Treatment System .............................................. 110 Figure 16 Peak Day Flow Scenario Used to Evaluate Risk to Effluent Quality with Tertiary Filter Bypass .......... 112 Figure 17 New and Existing Kitchener WWTP Outfalls ..................................................................................... 121 Figure 18 Cross Section of Diffuser Structure ................................................................................................... 123 Figure 19 Simplified Process Flow Schematic of the Plant 3 and 4 Secondary Treatment System (One

Treatment Train Shown) .................................................................................................................... 124 Figure 20 Kitchener WWTP Plants 3 and 4 Simplified Schematic ..................................................................... 125 Figure 21 Plant 3 and Plant 4 Aeration Tank Distribution Channels Schematic ................................................. 129 Figure 22 Plant 3 and Plant 4 Aeration System Configuration ........................................................................... 131 Figure 23 Simplified Plan View Schematic of the Kitchener WWTP Upgrades RAS/WAS Pumping Station

Design .............................................................................................................................................. 139 Figure 24 Simplified Process Flow Schematic of the Liquid Train of the WAS Thickening System..................... 150 Figure 25 Typical Primary Sludge Pumping Cycle Based on a 120 Minute Cycle and 5 Minute Pump Time

per Hopper at the Design Sludge Flow Rate ...................................................................................... 168 Figure 26 Relocation of Plant 1 Blowers ........................................................................................................... 175 Figure 27 Projected Annual Cash Flow for Kitchener WWTP Upgrades ............................................................ 239 Figure 28 Revised Site Plan Based on Relocation of Energy Centre and Thickening Building ............................ 242 List of Tables

Table 1 Summary of the Three Design Phases and Construction Administration Phase ..................................... 3 Table 2 Overview of Phase 3 Upgrade Contracts ............................................................................................... 5 Table 3 Process Design Memoranda Prepared During the Preliminary Design Process ..................................... 6 Table 4 Summary of Biosolids Exceedances in Lagoon 1................................................................................. 14 Table 5 Summary of Clay Liner Exceedances in Lagoon 1 ............................................................................... 14

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Table 6 Summary of Biosolids Exceedances in Lagoon 2................................................................................. 16 Table 7 Summary of Clay Liner Exceedances in Lagoon 2 ............................................................................... 16 Table 8 Summary of Soil Analytical Parameters Exceeding Guidelines ............................................................ 18 Table 9 Summary of Groundwater Analytical Parameters Exceeding Guideline ................................................ 18 Table 10 Technical Memoranda Prepared During Site Wide Facility Plan Process ............................................. 20 Table 11 Permit and Approval Requirements for Construction............................................................................ 21 Table 12 Description of Primary Clarifiers .......................................................................................................... 26 Table 13 Description of Secondary Treatment Processes .................................................................................. 27 Table 14 Preliminary Estimate of Greenhouse Emissions .................................................................................. 29 Table 15 Certificate of Approval Plant Rated Capacity ....................................................................................... 30 Table 16 Existing Treatment Objective and Non-Compliance Limits ................................................................... 30 Table 17 Kitchener WWTP Raw Wastewater Flow Peak Factors........................................................................ 32 Table 18 Design Flows ...................................................................................................................................... 32 Table 19 Raw Wastewater Characterization and Design Loading ....................................................................... 32 Table 20 Anticipated Certificate of Approval Effluent Requirements ................................................................... 33 Table 21 Projected Sludge Production and Quality............................................................................................. 33 Table 22 Odourous Emissions (XCG, 2007)....................................................................................................... 35 Table 23 Qualitative Assessment of Odourous Emissions, Plant Wide ............................................................... 37 Table 24 Comparison of Primary Effluent Distribution Options............................................................................ 41 Table 25 Existing Boilers and Digester Gas Boosters ......................................................................................... 42 Table 26 Boiler Comparison Life-Cycle Costing (Based on 5% interest, 2% inflation) ......................................... 44 Table 27 Digester Configuration Option Comparison .......................................................................................... 47 Table 28 Overview of Mobile Dewatering Equipment Options............................................................................. 55 Table 29 Biosolids and Soil Cover Process Option Advantages, Disadvantages and Feasibility ......................... 57 Table 30 Lagoon Biosolids and Impacted Berm Material Disposal Option Advantages, Disadvantages and

Feasibility ............................................................................................................................................ 58 Table 31 Estimated Volumes and Thicknesses of Supernatant in Lagoon 1 and Lagoon 2 ................................. 60 Table 32 Estimated Volumes and Thicknesses of Biosolids in Lagoon 1 and Lagoon 2 ...................................... 60 Table 33 Estimated Volumes and Thicknesses of Clay Liner in Lagoon 1 and Lagoon 2 .................................... 60 Table 34 Digested Sludge Transfer Pumps Design Criteria ................................................................................ 71 Table 35 Design Specifications for Digested Sludge Transfer Pump and Surge Protection Systems ................... 72 Table 36 Available NPSH for Digested Sludge Transfer Piping Option 1 ............................................................ 74 Table 37 Available NPSH for Digested Sludge Transfer Piping Option 2 ............................................................ 74 Table 38 Available NPSH for Digested Sludge Transfer Piping Option 3 ............................................................ 74 Table 39 Indoor Design Criteria for Digested Sludge Transfer Pumping ............................................................. 75 Table 40 Anaerobic Digester Design Criteria ...................................................................................................... 82 Table 41 Preliminary Design Specifications for Anaerobic Digesters .................................................................. 82 Table 42 Design Criteria for Digester Mixing ...................................................................................................... 83 Table 43 Preliminary Design Specifications for Digester Mixing .......................................................................... 83 Table 44 Design Criteria for Digester Heating and Recirculation ........................................................................ 84 Table 45 Preliminary Design Specifications for Digester Heating and Recirculation ............................................ 84 Table 46 Design Criteria for Digester Gas Handling System ............................................................................... 85 Table 47 Preliminary Design Specifications for Digester Gas Handling System .................................................. 85

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Table 48 Indoor Design Criteria Applicable to the Anaerobic Digestion System .................................................. 87 Table 49 Ventilation Rates for the Anaerobic Digestion Systems ........................................................................ 88 Table 50 Design Criteria for Screens and Screenings Handling .......................................................................... 93 Table 51 Preliminary Design Specification for Screens and Screenings Handling ............................................... 94 Table 52 Design Criteria for Grit Removal System ............................................................................................. 96 Table 53 Preliminary Design Specifications for Grit Removal ............................................................................. 96 Table 54 Design Criteria for De-gritted Wastewater Pumping ............................................................................. 98 Table 55 Preliminary Design Specification for De-gritted Wastewater Pumping .................................................. 98 Table 56 Design Criteria for Phosphorus Removal Chemical System ............................................................... 100 Table 57 Preliminary Design Specifications for Phosphorus Removal Chemical System .................................. 100 Table 58 Odour Control Airflow Rates by Area ................................................................................................. 103 Table 59 Preliminary Design Specifications for Ductwork and Associated Equipment ....................................... 104 Table 60 Preliminary Design Specifications for Odour Control Units ................................................................. 104 Table 61 Preliminary Design Specifications for Odour Control Fans ................................................................. 104 Table 62 Indoor Design Criteria for the Headworks Building ............................................................................. 106 Table 63 Ventilation Rates for the Headworks Building .................................................................................... 107 Table 64 Peak Day Effluent TP with one Tertiary Filter Off-Line ....................................................................... 112 Table 65 Design Criteria for Tertiary Disk Filters .............................................................................................. 113 Table 66 Preliminary Design Specification for Tertiary Disk Filters (Aquadisk®) ............................................... 113 Table 67 Design Criteria for Filter Backwashing ............................................................................................... 114 Table 68 Preliminary Design Specifications for the Filter Backwashing System ................................................ 115 Table 69 Design Criteria for Tertiary Bypass System ....................................................................................... 116 Table 70 Preliminary Design Specifications for Tertiary Bypass System ........................................................... 116 Table 71 Indoor Design Criteria for the Tertiary Filtration Building .................................................................... 118 Table 72 Proposed Ventilation Rates for the Tertiary Filtration building ........................................................... 119 Table 73 Available Head at Kitchener WWTP Outfall ....................................................................................... 122 Table 74 Headloss through New Kitchener WWTP Outfall ............................................................................... 122 Table 75 Design Criteria for the Primary Effluent Flow Splitting Chamber ......................................................... 126 Table 76 Preliminary Design Specifications for the Primary Effluent Flow Splitting Chamber ............................ 126 Table 77 Design Criteria for the Plant 3 and Plant 4 Aeration Tanks ................................................................. 128 Table 78 Preliminary Design Specifications for the Plant 3 and Plant 4 Aeration Tanks. ................................... 128 Table 79 Design Criteria for the Plant 3 and Plant 4 Oxygen Demand .............................................................. 132 Table 80 Design Criteria for the Plant 3 and Plant 4 Fine Bubble Diffuser System (per tank) ............................ 132 Table 81 Preliminary Design Specification for the Plant 3 and Plant 4 Blowers ................................................. 133 Table 82 Preliminary Design Specification for the Plant 3 and Plant 4 Fine Bubble Diffusers ............................ 133 Table 83 Design Criteria for the Aeration Tank Unwatering Pumps .................................................................. 134 Table 84 Preliminary Design Specifications for the Aeration Tank Unwatering Pumps ...................................... 134 Table 85 Design Criteria for the Plant 3 and Plant 4 Secondary Clarifiers ......................................................... 136 Table 86 Preliminary Design Specification for the Plant 3 and 4 Secondary Clarifiers ....................................... 136 Table 87 Design Criteria for the Secondary Clarifier Unwatering System .......................................................... 137 Table 88 Design Criteria for the Scum Pumping System .................................................................................. 138 Table 89 Preliminary Design Specifications for the Scum Pumping System ...................................................... 138 Table 90 Design Criteria for RAS and WAS Pumps.......................................................................................... 140

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Table 91 Preliminary Design Specifications for RAS Pumps ............................................................................. 141 Table 92 Preliminary Design Specifications for WAS Pumps ............................................................................ 141 Table 93 Indoor Design Criteria for Plant 3 and 4 Secondary Treatment and Plant 2 RAS/WAS Pumping

Station .............................................................................................................................................. 143 Table 94 Ventilation Rates for Plant 3 and 4 Secondary Treatment and Plant 2 RAS/WAS Pumping

Station .............................................................................................................................................. 144 Table 95 Preliminary Design Specifications for WAS Holding Tanks ................................................................ 152 Table 96 Design Criteria for RDTs ................................................................................................................... 153 Table 97 Preliminary Design Specification for RDTs ........................................................................................ 153 Table 98 Design Criteria for Thickening Filtrate Tank ....................................................................................... 153 Table 99 Preliminary Design Specification for Thickening Filtrate Tank ............................................................ 154 Table 100 Design Criteria for Thickened Sludge Holding Tank ........................................................................... 155 Table 101 Preliminary Design Specification for Thickened Sludge Holding Tank ................................................ 155 Table 102 Design Criteria for WAS Thickening Polymer System ....................................................................... 156 Table 103 Preliminary Design Specification for Thickening Polymer System ..................................................... 157 Table 104 Odour Control Airflow Rates ............................................................................................................. 159 Table 105 Preliminary Design Specifications for Ductwork and Accessories ...................................................... 159 Table 106 Preliminary Design Specifications for Odour Control Units ................................................................. 160 Table 107 Preliminary Design Specifications for Odour Control Fans ................................................................ 160 Table 108 Indoor Design Criteria for the Thickening Building ............................................................................. 162 Table 109 Ventilation Rates for the Thickening Building ..................................................................................... 163 Table 110 Design Criteria for Primary Sludge Collection Equipment................................................................... 166 Table 111 Preliminary Design Specification for Primary Sludge Collection Equipment ........................................ 167 Table 112 Design Criteria for Raw Sludge Pumping Equipment ......................................................................... 167 Table 113 Preliminary Design Specification for Raw Sludge Pumping and Grinding Equipment ........................ 168 Table 114 Preliminary Design Specification for Primary Clarifier Scum Removal Equipment ............................. 169 Table 115 Design Criteria for Secondary Clarifier Collection Equipment ............................................................ 172 Table 116 Preliminary Design Specification for Secondary Clarifier Collection Equipment ................................. 172 Table 117 Design Criteria for Secondary Scum Pumping .................................................................................. 173 Table 118 Preliminary Design Specification for Secondary Scum Pumping Equipment ...................................... 173 Table 119 Effluent Water Demands .................................................................................................................. 174 Table 120 Preliminary Electrical Load at the Kitchener WWTP with Planned Upgrades ..................................... 183 Table 121 Estimated Standby Power Loads ...................................................................................................... 184 Table 122 Building Code Climatic Design Data ................................................................................................. 194 Table 123 Unit Self Weight ............................................................................................................................... 194 Table 124 Design Live Loads............................................................................................................................ 195 Table 125 Unit Weight of Materials ................................................................................................................... 195 Table 126 Live Load Deflection Limits ............................................................................................................... 195 Table 127 Overview of Structural Materials ....................................................................................................... 196 Table 128 Indoor Design Criteria ...................................................................................................................... 197 Table 129 Outdoor Air Filtration Criteria ............................................................................................................ 198 Table 130 Space Pressurization Controls Criteria ............................................................................................. 199 Table 131 Comparison of 2006 OBC Requirements and Proposed Building P Values ....................................... 209

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Table 132 Energy Impact of Energy Reduction Measures Applied to Headworks and Thickening Buildings Ventilation Air .................................................................................................................................... 211

Table 133 Energy Impact of Energy Reduction Measures Applied to RAS/WAS and Digester Buildings Ventilation Air .................................................................................................................................... 211

Table 134 Recommended Voltage Levels For various Types Of Electrical Equipment ........................................ 213 Table 135 Proposed Contract Sequencing Plan ................................................................................................. 218 Table 136 Potential Process Shutdowns ........................................................................................................... 223 Table 137 Major Equipment Pre-Selection Recommendation ............................................................................. 234 Table 138 Summary of Project Costs ................................................................................................................ 237 Table 139 Projected Annual Cash Flow for Kitchener WWTP Upgrades ............................................................ 238 Table 140 Operation and Maintenance Cost Estimate ........................................................................................ 240 Table 141 Region of Waterloo Input on Outstanding Preliminary Design VE Items ............................................. 242 Table 142 Final Recommendations for VE Alternative Implementation ............................................................... 243 Appendices

Appendix A Preliminary Design Drawings Appendix B Certificate of Approval Appendix C Process Design Memoranda

PDM 1 - Peak Factor Analysis PDM 2 - Gravity Primary Sludge Thickening PDM 3 - Digester Gas Storage PDM 4 - Design Basis Summary PDM 5 - Process Modeling PDM 6 - Comparison of Rectangular and Circular Secondary Clarifier Options PDM 7 - Digester Heating and Operation PDM 8 - Value Engineering Response

Appendix D Geotechnical Investigation Appendix E Soil Resistivity Testing Report Appendix F Structural Condition Survey Appendix G Designated Substances and Hazardous Building Materials Audit Appendix H Draft Hydrogeological Investigation Report Appendix I Lagoon Decommissioning Preliminary Design Report Appendix J Preliminary Process Control Narratives Appendix K Preliminary Process and Mechanical Equipment List Appendix L Aqua Aerobics™ Literature Appendix M Service Water Demand Breakdown Appendix N Preliminary LEED Scorecard Appendix O Hydraulic Calculations Appendix P Construction Figures and Tables Appendix Q Risk Register Appendix R Detailed Cost Breakdown

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1. Introduction 1.1 Authorization

AECOM was retained by the Region of Waterloo (Region) in 2010 to complete a Site Wide Facility Plan and Preliminary Design for the Phase 3 upgrades of the Kitchener Wastewater Treatment Plant (WWTP).

1.2 Background

The existing Kitchener WWTP is a conventional secondary treatment facility; a site plan (000-C101) of the existing plant is presented in Appendix A. The plant has a rated capacity of 122,745 m3/d, as approved in the current Certificate of Approval (C of A Sewage) (No. 8735-8HMJDH, issued June 9, 2011) and an amended Environmental Compliance Approval (ECA) (8735-8HMJDH, issued January 16, 2012) and an ECA (Air) (No. 3006-8NVPKU, issued March 30, 2012), also included in Appendix B. Figure 1 shows an aerial map of the Kitchener WWTP and surrounding residential land uses.

Figure 1 Aerial Map of Kitchener WWTP Site and Surrounding Land Uses

The Kitchener WWTP is comprised of two (2) separate secondary treatment plants served by a common headworks facility and primary clarifiers. Plant 1 was constructed in the early 1960s and Plant 2 was constructed in the mid-1970s. Both facilities discharge to a common chlorine contact chamber where chlorination and de-chlorination occur

True North

Project North

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prior to discharge through an outfall terminating in a submerged diffuser in the Grand River. Two (2) biosolids storage lagoons at the site have been used in the past for seasonal storage of biosolids from Kitchener WWTP. The Region has completed a number of background studies related to the Kitchener WWTP including the Wastewater Treatment Master Plan (Earth Tech, 2008) and the Middle-Grand River Assimilative Capacity Study (Stantec, 2010). These studies established a need to undertake significant upgrades to the Kitchener WWTP to improve reliability, operational effectiveness and effluent quality in order to protect the receiving stream and downstream users. The Region has initiated a three (3) phase program of upgrade projects related to the Kitchener WWTP. Phase 1 includes the construction of the Wastewater Residuals Management Centre (WWRMC), located offsite at 440 Manitou Drive in the City of Kitchener. Upon completion of Phase 1, centrate will be returned for treatment at the Kitchener WWTP. The Phase 2 upgrades will improve the ability of Plant 2 to treat centrate and enhance ammonia removal in the aeration facility. A new UV disinfection and effluent pumping station facility is also being constructed to ensure appropriate levels of disinfection are met and non-acutely toxic effluent is released to the Grand River. The third phase of upgrades will provide reliable and efficient operation in the long term, and address additional Grand River water quality requirements. The Phase 3 upgrades will include the decommissioning and demolition of the biosolids storage lagoons, construction of new Plant 3 and 4 secondary treatment trains, and the decommissioning and demolition of Plant 1, as well as a number of upgrades to address deficiencies throughout the plant, as outlined in the Site Wide Facility Plan (AECOM, 2011). This Preliminary Design Report (PDR) is intended to identify the recommended selection of process treatment alternatives, determine the required sizing of selected equipment / tanks and identify all ancillary needs such as electrical, building envelope, and instrumentation and control. The PDR also documents the expected time frame and costs (construction and operational) for the proposed works. The PDR will form the basis of the detailed design report. The PDR represents approximately the 30% design level, although certain aspects (process in particular) have been developed well beyond the 30% level while other aspects (site works in particular), which are dependent on design details, have been developed only to the conceptual level. Due to the magnitude and complexity of this project, the work will be carried out through a number of construction contracts over a period of approximately 10 years. The PDR presents a Contract Staging Plan as well as a cash flow projection (in 2012 dollars). The PDR has been laid out generally in conformance with the Region of Waterloo Transportation and Environmental Services Wastewater Design Standard 52005 - Preliminary Design Report (Region of Waterloo, 2009). Some customization has been required to reflect the nature of this specific project.

1.3 Approach

The Kitchener WWTP Phase 3 upgrades design is being carried out over three stages: Site Wide Facility Plan, Preliminary Design, and Detailed Design. After the completion of the detailed design a fourth stage, Construction Administration, will be carried out. A Schedule B Class Environmental Assessment is being conducted in conjunction with the preliminary design activities. The purpose of the Site Wide Facility Plan was to evaluate alternative approaches and select preferred approaches to more fully define the scope of work for the upgrades. Decisions from the Site Wide Facility Plan were carried forward to the Preliminary Design Phase. The Preliminary Design builds on the Site Wide Facility Plan to further advance the progress of the design, including incorporating optimizations and refinements generated both as part of the Preliminary Design efforts and the value engineering completed at the end of the Preliminary Design phase.

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During the Detailed Design Phase, the design will be developed further to produce drawings and specifications with sufficient detail for tender. The scope of the three (3) design phases and the construction administration phase are summarized in Table 1 Table 1 Summary of the Three Design Phases and Construction Administration Phase

Site Wide Facility Plan Preliminary Design Detailed Design Construction Administration

Design flows, capacity and effluent criteria

Process selection General layout and configuration Process flow and mass balance High level cost estimate Preliminary drawings (~1% of

total) Specifications – budget

quotations for major equipment

Optimization of process sizing Equipment selection, sizing and

functional specification Hydraulic profile Functional integration of

components typically organized by engineering discipline

High level cost estimate Contracting plan Drawings (~10% of total) Specifications – catalogue cuts,

equipment data sheets, equipment budget quotations

Preparation of contract documents, pre-purchase, general contract terms and conditions

Preparation of contract packages according to contracting plan

Cost estimate Drawings (100% of total) Specifications (Divisions 1 – 16)

Shop Drawing Reviews Responding to Contractor

RFIs Construction Change

Management Recommendation of

Progress Payments Sub consultant

management as required Attendance of Construction

Progress Meetings Site inspection

1.4 Objectives

The Region’s objectives for the Phase 3 upgrades are to deliver an upgraded Kitchener WWTP that meets the following: Reliable long-term operation and performance: new processes and process upgrades to meet new effluent

criteria by 2018 and provide capacity for future design loads, and address existing limitations related to operations, maintenance, process equipment and structural deficiencies, process control and monitoring, health and safety and current design codes

Fully integrated facility: fully integrate existing processes and facilities with new facilities, so that the upgraded Kitchener WWTP will function as a single facility

Sustainability and environmental protection: incorporate sustainability in the upgrades as appropriate, to minimize energy use and greenhouse gas emissions, minimize the use of materials and chemicals, recover resources, reduce biosolids generation and enhance the natural environment

Respect and protect neighbours: design and construct the upgrades in a manner that protects the community surrounding the plant, is compatible with the limited access to the site, and ensures continuous operation and performance during the construction period

Value: develop a final design and construction plan by evaluating capital, operating and life-cycle costs of all options, so that the Region realizes the highest value in achieving its goals

1.5 Class Environmental Assessment

A Schedule B Municipal Class Environmental Assessment (EA) planning process (AECOM, 2012b) was initiated in June 2011 to address the potential impacts from the various WWTP upgrade components and communicate to the public-review agencies how the Phase 3 Upgrades will be designed and constructed. The most significant environmental constraints to constructing the upgrades primarily relate to the new Grand River outfall and removal of the existing outfall once the new outfall is commissioned. Construction of this new outfall will result in the disturbance of tree and wetland communities and fish habitat. There is also the potential for impacts to several designated Species at Risk. Potential impacts to these features and ways to avoid or mitigate them have been or will be addressed in the Class EA Environmental Study Report (ESR) including supporting ecological investigations and future Grand River Conservation Authority (GRCA), Department of Fisheries and Oceans (DFO)

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and the Ministry of Natural Resources (MNR) permitting process to be completed as part of the detailed design. Other possible outfall constraints include the potential to encounter archaeological resources. Additional field studies will be conducted prior to final design of the outfall so that detailed construction, mitigation and monitoring plans can be developed and incorporated into the Contract Documents.

1.6 Scope of Work

The Phase 3 Upgrades will consist generally of the following new elements: Twinning and redirection of a portion of the incoming raw sewage conduit Headworks (screening and grit removal) Plant 3 and 4 secondary treatment Tertiary treatment Energy Centre, including co-generation and standby power Sludge thickening Outfall New administration building Odour control

The Phase 3 Upgrades will include upgrades to or replacement of the following existing facilities: Digestion facilities Plant 2 return activated sludge/waste activated sludge (RAS/WAS) pumping Administration/maintenance building Primary clarifier sludge mechanisms Primary/digested sludge pumping Plant 2 secondary clarifier mechanisms Miscellaneous minor plant and site upgrades The Phase 3 Upgrades will include decommissioning and/or demolition of the following existing facilities: Sludge lagoons and associated sludge pumping facilities Existing Headworks Building Old administration building Plant 1 Buried sludge storage tanks Plant 2 RAS/WAS Pumping

An overall site plan (100-C102) that presents all proposed works is contained in Appendix A. Also included in Appendix A are process flow diagrams and the hydraulic profile of the Kitchener WWTP Phase 3 upgrades. The Phase 3 Upgrades have been grouped into 5 main contracts. The use of multiple contracts gives the Region improved project staging and cash flow control. Several of the contracts will be further broken into smaller contracts based on schedule and/or the nature of the works to be undertaken. The 5 main contracts are: Contract 1 – Lagoon Decommissioning and Digested Sludge Transfer Pumping Contract 2 – Energy Centre and Anaerobic Digestion Contract 3 – Headworks, Tertiary Treatment, and Outfall Contract 4 – Plant 3 and 4 Secondary Treatment, Plant 2 RAS/WAS pumping, and some miscellaneous works

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Contract 5 – Administration Building/Maintenance Building and Sludge Thickening and some miscellaneous works

These contract packages were selected based on the timing and spatial separation requirements, type of work, and contract value. The contracts and staging have also taken into consideration the other works currently underway including the Plant 2 Upgrades and the UV disinfection and effluent pumping construction. A brief overview of the Phase 3 upgrade contracts are presented in Table 2 Table 2 Overview of Phase 3 Upgrade Contracts Contract Components Description Approx.

Timing

1a Lagoon Decommissioning

Decommission the existing sludge lagoons and prepare site for construction of new Plant 3 facilities

2012/13

1b Digested Sludge Transfer Pumping Construct new pumping system to pump digested sludge to WWRMC 2012/13

2a Energy Centre Construct new power supply and energy centre including standby power 2013/15

2b Anaerobic digestion Digester modifications 2013/15

3a Headworks Headworks including screening and grit removal 2013/15

3b Tertiary Treatment Outfall

Tertiary filtration system, new outfall sewer and diffuser 2015/17

4

Plant 3 and 4 Secondary Treatment Plant 2 Upgrades

New Plant 3 and 4 aeration tanks, secondary clarifiers, RAS/WAS pumping stations, blowers and chemical dosing.

Plant 2 RAS/WAS pumping station Minor Plant 2 upgrades

2015/18

5a New Admin Building Modifications to existing administration building

New Administration Building including laboratory and modifications to existing Maintenance Building. 2018/20

5b Sludge Thickening Sludge thickening 2018/20

- Miscellaneous plant and site upgrades

Plant 1 decommissioning and miscellaneous plant and site upgrades.

1.7 Value Engineering

The Kitchener WWTP Phase 3 Upgrade Preliminary Design Report was subject to a Value Engineering (VE) study by a multidiscipline team lead by a VE facilitator. The VE team identified 26 VE Alternatives with performance and/or cost savings potential and 20 design suggestions that are expected to result in performance improvements, constructability enhancements, and/or non-quantifiable cost savings. The final categorization of the VE Alternatives, based on decisions made at the VE Implementation meeting, included 10 alternatives that are Recommended (R), 21 alternatives that will be considered during detailed design (C) and 14 alternatives that are Not Recommended (NR) (one option was included under 2 categories). A number of decisions have been deferred until detailed design and/or need further clarification. The Preliminary Design Value Engineering is described in detail in Section 21 and in Process Design Memorandum 8, contained in Appendix C.

1.8 Previous Reports

1.8.1 Process Design Memoranda

A series of process design memoranda (PDM), presented in Table 3, were prepared over the course of the development of the Preliminary Design.

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Table 3 Process Design Memoranda Prepared During the Preliminary Design Process PDM Number Title

1 PDM 1 – Peak Factor Analysis

2 PDM 2 – Gravity Primary Sludge Thickeners

3 PDM 3 – Digester Gas Storage

4 PDM 4 – Design Basis Summary

5 PDM 5 – Modeling Results

6 PDM 6 – Comparison of Rectangular and Circular Secondary Clarifier Options

7 PDM 7 – Digester Heating and Operation

8 PDM 8 – Value Engineering Response

PDMs number 1 through 8 are contained in Appendix C.

1.8.2 Additional Background Data Collection and Assessment Work

1.8.2.1 Geotechnical Investigation

AECOM prepared a Terms of Reference and solicited bids on behalf of the Region to conduct a geotechnical investigation specific to the areas that will be impacted by construction of new structures. SPL Consultants Limited (SPL) carried out the geotechnical investigation throughout the proposed construction site. In general, the work program consisted of: 1. determining and reporting on geotechnical parameters required for facility design; 2. classification and testing of the soil for engineering properties (e.g., Standard Proctor Densities and corrosivity); 3. recording groundwater elevations and reporting on groundwater control and dewatering measures required, and

identifying the potential for any well interference and potential for the need of a permit to take water (PTTW); 4. assessing any other conditions that could potentially affect the design or construction methods of the foundation

for the proposed structures and buried services (e.g., soil improvements, backfill, compaction, requirements, shoring, rock breaking methods);

5. providing recommendations for foundation design parameters, bearing capacity of SLS and ULS Design; 6. providing recommended earthquake factors; 7. providing recommendations for protection of uplift of the structures under flood condition; 8. providing recommendations for trench excavation methodologies; 9. providing recommendations for direct drilling or tunneling for a portion of the buried services; 10. assessing soil corrosions to identify soils that may have a determinately effect on construction materials; and 11. performing soil resistivity testing for each layer of soil to supplement design of grounding systems and/or

grounding rods. The scope of the geotechnical investigation was somewhat limited due to access restrictions in the area of Plant 2 and the UV disinfection building due to ongoing constructions activity. In addition, access to the lagoons was restricted due to the presence of sludge and supernatant. These areas will require additional investigation during detailed design. The details of the geotechnical investigation are presented in a report prepared by SPL (2012), presented in Appendix D. A brief overview of the important findings of the report is presented in this section.

1.8.2.1.1 Site and Regional Geography

The Kitchener WWTP lies within the physiographic area of the Waterloo Moraine. The Waterloo Moraine is a complex deposit consisting of sand, gravel, till and discontinuous units of finer-grained sediments that were

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deposited during the Wisconsinan glaciations. The overburden sediments range in thickness from 30 m to 120 m in the area of the Waterloo Moraine.

1.8.2.1.2 Subsurface Conditions

The boreholes revealed the presence of a variety of soil types ranging in texture from silt to sand and gravel and glacial till deposits. Fill materials were found from depths between 1.5 m and 9.2 m below existing grade (i.e., elevations between 282.6 m and 275.7 m) in all boreholes. An alluvial deposit of clayey silt and/or silty sand was found to underlie the fill in most boreholes. The alluvial deposits contained organic matter or peat in several boreholes. Cohesionless deposits of silt, sandy silt/silty sand, sand, gravelly sand, and sand and gravel deposits are predominant on the site and were encountered in all of the boreholes. Cobble/boulder sizes were observed throughout the granular deposits. Standard Penetration Tests performed in these deposits yielded ‘N’-values generally ranging from 10 to in excess of 50 blows/0.3 m, indicating a generally compact to very dense material.

1.8.2.1.3 Groundwater Conditions

In initial groundwater level monitoring, the depth to groundwater varied between 3.4 and 6.4 mbgs for the initial readings (between elevations of 277.1 and 278.7 m). Subsequent groundwater levels were found to be between 3.2 and 6.6 mbgs (between elevations of 276.9 and 278.8 m). Over the long term, seasonal fluctuations in the groundwater level are expected; SPL recommended further monitoring of piezometric levels.

1.8.2.1.4 Geotechnical Interpretation and Recommendations

Foundations

New Headworks Building

The proposed founding elevation of the new Headworks Building is at or below 279.5 m. SPL indicated that due to the bouldery nature of the deposits that were encountered below the fill, and the basal heave and caving issues that are possible in the wet granular soils, conventional drilled caissons are not a feasible option for the site. SPL recommended the options of foundations on engineered fill or continuous flight auger (CFA) piles, although driven piles are another alternative. SPL noted that additional boreholes are recommended to be drilled to 3 m below refusal (defined as material for which SPT “N” values exceed 100) to confirm competent soil conditions for these options during the detailed design phase.

New Administration Building

The new administration building will be a two-storey building with no basement. Finished grade is expected to be around 282.0 m. The proposed structure can be supported by spread and strip footings founded on engineered fill for a bearing capacity of 200 kPa at the serviceability limit states (SLS) and for a factored geotechnical resistance of 300 kPa at the ultimate limit states (ULS), provided that all requirements are adhered to. Where engineered fill is used to support the foundations, the floor slab can also be supported by engineered fill. Alternatively, if the fill is to be left in place, the building can be supported by continuous flight auger piles, which will require a structural slab.

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New Aeration Tanks, Secondary Clarifiers and RAS/WAS Pumping Stations

The new aeration tanks will contain over 5 m of water and are proposed to be founded at or below 278.5 m. The aeration tanks, secondary clarifiers and RAS/WAS pumping station can be supported by spread and strip footings or mat foundations founded on engineered fill for a bearing capacity of 200 kPa at the SLS and for a factored geotechnical resistance of 300 kPa at the ULS, provided that all requirements are adhered to. SPL recommends a minimum value of 15 MPa/m for modulus of subgrade reaction for large footings.

New Energy Centre and Thickening Facility

The New Energy Centre houses heavy electrical equipment and will be a one-storey building with no basement. The New Thickening Facility is a two-storey structure with a basement level. The basement floor elevation is expected to be at 280 m with founding elevation at or below 279.5 m. The groundwater level was measured to be 3.9 (mbg) (an elevation of 278.8 m) in the monitoring well installed in BH27. The Kitchener Phase 3 Upgrades buildings can be supported by spread and strip footings founded on native soils or engineered fill for a bearing capacity of 200 kPa at the SLS and for a factored geotechnical resistance of 300 kPa at the ULS, provided that all requirements are adhered to. Prior to the placement of the engineered fill, all existing fill and surficially softened native soils must be removed and the exposed surface proof rolled. Any soft spots revealed during proof rolling must be sub-excavated and re-engineered.

General Notes on Foundations

Footings designed to the specified allowable bearing capacity at the SLS are expected to settle less than 25 mm total and 19 mm differential.

Uplift Pressure

The site lies within the Grand River floodplain and has a design flood level of 283.6 m. If construction is carried out at a time when the river level is higher than the level at the time of the investigation, a corresponding increase in groundwater levels should be anticipated. When evaluating uplift pressures, the ground water level should be assumed to be at the Grand River design flood level. If the combination of the structure weight and the mobilized frictional resistance between the buried portion of the exterior walls and the backfill materials is insufficient to resist the uplift forces during any stage of the construction and/or during the operation of the structure, then a perimeter and subfloor drainage system complete with dedicated sump, pumps and high-level alarm system, as well as permanent wells must be provided. Alternatively, a fail-safe system would employ grouted ground anchors. When checking the overall stability of the structures, SPL recommends that the design should incorporate a minimum safety factor of 1.1 when using only the dead weight of the structures and 1.3 if soil anchors are used.

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Soil Anchors

For soil anchor design, SPL recommends a bond value of 48 kPa for compact to dense native soil and 15 kPa for loose or fill material; these values depend on anchor installation methods and grouting procedures. In no case should the bonded length be less than 4m. SPL recommends that the actual capacity (bond resistance) of the anchors should be established by at least two (2) full scale pull-out tests (“performance test”) in accordance with Canadian Foundation Manual (4th edition), testing to 200% of working load. Each installed anchor must be proof loaded to 1.33 times the design working load, in accordance with Post-Tensioning Institute (PTI) guidelines.

Earthquake Consideration

Multi-channel analyses of surface wave (MASW) were carried out by Geophysics GPR International Inc. at three locations across the site. The full report is presented in the appendices of the SPL Report (2012), presented in Appendix D. Based on the field seismic shear wave velocity measurements and according to Table 4.1.8.4.A of Ontario Building Code (OBC) 2006, the site of the Kitchener WWTP Phase 3 Upgrades structures founded on engineered fill or the native soils can be classified as ‘Class C’ for seismic site response.

Construction Considerations: Excavations and Dewatering

Excavations for the new structures can be carried out using heavy hydraulic backhoes. Provisions should be included in the contract for the excavation and disposal of boulders and obstructions in the fill. It is expected that some of the excavations will penetrate the permanent groundwater table, based on the piezometric water level measurements taken in the installed monitoring wells (elevations ranged from 276.9 m to 278.7 m). Perched water in the fill should also be expected; however, this perched water should be manageable using perimeter ditches, sumps and appropriately sized filtered pumps. This material will be easily disturbed and susceptible to sloughing during excavation, and may require flatter excavation slopes. It should be noted that positive dewatering, such as by deep wells or well points/educators, will be required prior to any excavation below the water table, at an approximate elevation of 278.5 m. Based on the borehole information, SPL notes that it may be possible to carry out the dewatering by pumping from perimeter sumps and trenches to control the seepage water from fill from above 278 m and to lower the groundwater level by approximately 0.5 m. The groundwater must be lowered to 1.0 m below the base of the lowest excavation level. SPL indicated that the rate of groundwater seepage into excavations below the groundwater table will be in excess of 50,000 litres/day. A Ministry of the Environment (MOE) PTTW will be needed for the temporary construction dewatering; the need for temporary construction dewatering should be confirmed by means of a pumping test prior to construction.

Underground Services: Pipe Support and Bedding

In the undisturbed state, the compact to dense fill identified at the site provides adequate support for service pipes and will allow the use of normal Class B type bedding. SPL recommends that the bedding material consist of well-graded granular material such as Granular ‘A’ (OPSS 1010) compacted to 98 percent Standard Proctor Maximum Dry Density (SPMDD).

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Subsurface Concrete and Corrosivity

Six (6) soil samples were tested for pH and water soluble sulphate content in order to evaluate the subsoil conditions for possible sulphate attack on concrete. The pH reading range was from 7.58 to 8.78 and the water soluble sulphate content ranged from 7 to 209 ppm. According to Table 3 of CSA Standard, CAN/CSA-A23.1-09 the degree of exposure to sulphate attack is Negligible; therefore, SPL indicated that normal Portland cement can be used in the subsurface concrete. Based solely on the AWWA/ANSI rating system, the fill material in BH4 is highly supportive of corrosion. However, SPL noted that more recent studies on the properties of local soils and their relationship with water main corrosion, conducted by the University of Toronto (Doyle et al., 2003) have showed that the foregoing AWWA/ANSI rating system is not a reliable predictor of a soils potential to support corrosion. Doyle et al.. (2003) suggest that, of the test parameters included in the AWWA/ANSI rating system, soil resistivity had the best correlation with external water main pitting depth. Doyle et al.. (2003) concluded that all soils with resistivity less than 2000 Ohm-cm could be supportive of corrosion to ferrous metals. Based on that generalization, the fill material in BH4 is considered to be corrosive.

Geotechnical Quality of Excavated Soils

Select fill and native soils can be used as general construction backfill where they can be compacted with sheep's foot type compactors. Fill containing organic matter and boulders should be removed and should not be used as structural fill. Loose lifts of soil, which are to be compacted, should not exceed 200 mm. The native soils above the ground water table are expected to be at or above their optimum moisture contents and will require moisture conditioning (drying out) prior to re-use as construction fill. Materials below the groundwater table will also have to be aerated and dried out prior to re-use. SPL recommends that imported Granular 'B' fill be used for engineered fill and where free draining material is required. It should be noted that the moisture content of excavated soils are subject to increase during wet weather, which would make these materials too wet for adequate compaction. Stockpiles should therefore be compacted at the surface or be covered with tarpaulins to minimize moisture uptake.

Environmental Quality of Excavated Soils

The soil samples submitted for analysis met the Table 1, Table 2 RPI and Table 2 ICC standards for all parameters analysed with the exception of sodium adsorption ratio (SAR). Soil sample BH4 SS4, collected from a depth of 2.3 to 2.9 mbgs exceeded the MOE Table 1 Standard for EC as well as the Table 2 RPI Standard for EC. Based on the analyses conducted, the soils on-site meet the MOE Table 2 ICC Standards for the parameters analysed. Therefore, SPL notes that excess soils generated onsite appear to be suitable for reuse on-site or for disposal at sites accepting fill that meets the MOE Table 2 ICC Standards.

Environmental Quality of Groundwater

The total suspended solids concentrations of groundwater samples collected from the monitoring wells exceeded the Region of Waterloo Sewer Use By-Law criteria; therefore, sediment control may be required prior to discharge to the Grand River. All metal parameters met applicable Region of Waterloo storm sewer by-law requirements, but several

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exceeded the provincial water quality objectives. Elevated un-ionized ammonia and total coliform levels were detected; groundwater quality will be monitored on an ongoing basis during detailed design.

1.8.2.1.5 Soil Resistivity Testing Performed

Geophysics GPR International Inc. performed soil electrical resistivity testing at the Kitchener WWTP, the final report on which is contained in Appendix E. A total of three (3) resistivity soundings were performed and 12 readings were taken at each sounding. Resistivity values were generally in the range of 10 and 400 Omh•m. A high resistivity reading of 6420.1 Omh•m was measured in Sounding B; resistivity values over 3000 Omh•m in Sounding B could be representative of bedrock.

1.8.2.2 Structural Assessment

A structural assessment was undertaken by AECOM as part of the baseline condition assessment conducted during the Site Wide Facility Plan and presented in detail in Technical Memorandum No. 1: Condition Assessment. A follow-up meeting was held with the Region, AECOM and the Ontario Clean Water Agency (OCWA) on June 22, 2011 to review the original condition survey. Many of the original findings/recommendations were in the process of being addressed by OCWA either as immediate action items or through development of repairs plans (such as a 5-year program for roofs). Many items will be addressed through the Phase 3 works either through repair or through replacement. The updated Condition Survey Table is presented in Appendix F. Key outstanding items are presented below.

1.8.2.2.1 Raw Sewage Influent Conduit

A number of joints and the bulkhead leak. A more detailed survey should be conducted during detailed design and the required repairs included in the Headworks Contract (No. 3).

1.8.2.2.2 Plant 2 RAS/WAS Pumping Station

Concrete spalling, cracks, exposed rebar, and handrail supports were identified in the Plant 2 RAS/WAS pumping station. Replacement of the pumping station will not take place until around 2018/19. A more detailed assessment should be conducted and interim concrete repairs implemented to ensure the reliability until the facility is replaced. Handrails are to be repaired.

1.8.2.2.3 Boiler Building

The basement floor and chamber ceiling of the blower building was identified to have severe spalling. This issue should be investigated early in detailed design and temporary repairs or restrictions put in place until Contract 2 is undertaken.

1.8.2.3 Designated Substances and Hazardous Building Materials Audit

AECOM prepared a Terms of Reference and solicited bids on behalf of the Region to conduct a designated substances survey of all areas that will be impacted by the Phase 3 upgrades. Between November 8 and 9, 2011, MTE Consultants, Inc (MTE) conducted the designated substance and hazardous materials audit at the Kitchener WWTP. The final report audit is contained in Appendix G. This audit was performed to identify potential designated substances and hazardous building materials prior to building maintenance, renovations, construction, and demolition activities as part of the Phase 3 Upgrades. The plant, which is approximately 180,000 m2 in size, consists of multiple one (1) and two (2) storey building structures occupying a total area of about 1,900 m2. A total of 16 buildings were audited, which consisted of a walk-through inspection of the buildings, collection of several samples from suspected hazardous materials [asbestos containing materials (ACM) and lead based paint/materials containing lead] that were submitted to IAT Laboratories (IATL) for laboratory analysis, and instrument identification methods. The audit also consisted of inspection for mercury containing bulbs/lighting fixtures; silica containing materials; polychlorinated biphenyl (PCB) containing

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materials; water damage and mould; urea formaldehyde foam insulation (UFFI) materials; and ozone-depleting substances (ODS).

1.8.2.3.1 Recommendations

The conclusions and recommendations presented in this section were made based on the work completed at the plant by MTE. It should be noted that several areas were inaccessible during the audit and should be inspected prior to proceeding with any building demolition or renovation activities.

ACM

Several ACM were identified at the Plant: Cementitious Insulation on pipe fittings Black Insulation on exterior pipe lines Transite asbestos products (panels, fume hoods and conduit) Window Caulking Vinyl Floor Tiles

At present, the risk to plant personnel is relatively low as long as these materials remain undisturbed. The ACM should be removed and properly disposed of prior to any renovation or demolition. Abatement of ACM must be performed in accordance with Ontario Regulation (O. Reg.) 278/05 under the Occupational Health and Safety Act (OHSA), and follow standard protocols for asbestos disposal per O. Reg. 558/00 (amending 347/90).

Lead

The lead concentrations exceeding the referenced guideline value was identified (in various materials at the plant): Paint Solder Pipe gaskets on sanitary drains Pipe gaskets/connections (plumbing fixtures) Ceramic tile glaze

Abatement or maintenance of any lead based materials/paints must be performed in accordance with the Ministry of Labour (MOL) Occupational Health and Safety Branch’s Lead on Construction Projects Guideline (September 2004).

Mercury

Fluorescent light tubes (approximately 300), fluorescent light bulbs (approximately 50), high-intensity discharge (HID) lamp bulbs (approximately 30), and thermostats/switches (approximately 5) containing mercury were identified in various buildings throughout the Plant. Prior to the demolition of a building, mercury bulbs, lighting fixtures and equipment must be properly removed and disposed of in accordance with Regulation 490/09 of OHSA and O. Reg. O. Reg. 558/00 (amending 347/90).

Silica

The following materials at the Plant were identified or suspected to contain silica: Brick Concrete, cement, and mortar Ceramic tile grout Rock and stone

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Sand, fill dirt, and topsoil Asphalt containing rock or stone Terrazzo Boiler refractory

Silica containing materials must be handled in accordance with MOL Occupational Health and Safety Branch’s Silica on Construction Projects Guideline (September 2004).

PCB

Several lighting fixtures and ballasts containing PCBs were noted in the buildings at the plant. Transformers or capacitors containing PCB were not identified at the Plant. PCB containing fixtures/ballasts must be managed in accordance with the PCB Regulations (Regulations/2008-273), made under the Canadian Environmental Protection Act, 1999.

Water Damage and Mould

Approximately 3 m2 of suspect mould amplification was observed on the plaster ceiling on a main floor storage room within the Administrative Building. Any mould remedial activities must be conducted in accordance with the Environmental Abatement Council of Ontario (EACO) 2010 Mould Abatement Guidelines or other industry accepted standards.

UFFI:

No UFFI was observed at the Plant.

ODS

One (1) central air conditioning (AC) unit, two (2) window mounted AC units, and three (3) domestic refrigeration units were observed. ODS must be removed recycled/disposed of in accordance with O. Reg. 189/94 and O. Reg. 558/00 (amending 347/90), and Federal ODS Regulations, 1998.

1.8.2.4 Lagoon Subsurface Investigation

During the fall of 2011, the Region retained MTE to conduct a subsurface investigation in the vicinity of the lagoons at the site. The objective of the investigation was to assess the quality of fill materials, native soil, biosolids, clay liner, and groundwater to assess the nature and extent of potential impacts resulting from the biosolids (if any) and to assess disposal options and requirements during lagoon decommissioning activities. The subsurface investigation consisted of the following: Advancement of eight (8) boreholes in and around the lagoons, all of which were converted to temporary

monitoring wells, to depths ranging from about 6.7 m to 11.3 meters below ground surface (mbgs) Sampling and analysis of soil and groundwater from each borehole/monitoring well installed Lagoon biosolids sampling and analysis Clay liner sampling and analysis

The following sections provide a brief summary of the results of the subsurface investigation competed by MTE; the final MTE Report (2012) detailing the lagoon subsurface investigation is presented in Appendix H.

1.8.2.4.1 Lagoon Biosolids and Underlying Clay Characterization and Results

The lagoons (biosolids and soil cover) and the upper portion of the clay liner were sampled and analyzed to assess the quality and disposal options as well as the suitability of biosolids and clay for disposal options. In total, two (2) locations were sampled in Lagoon 1 and eight locations were sampled in Lagoon 2. Only two (2) samples were

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collected in Lagoon 1 due to difficulty in moving the sampling barge across the entire lagoon. At each sampling location, two samples were collected; one from the biosolids and one from the top 30 cm of the clay liner. Samples were collected no deeper than 30 cm into the clay liner to ensure that the integrity of the liner was not compromised. Details of the sampling methodology are included in the MTE Report (2012). All samples collected were submitted to an accredited Canadian Association for Laboratory Accreditation (CALA) laboratory, ALS Environmental, for the analysis to measure metal (including As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Se, and Zn), E. coli, polychlorinated biphenyls (PCB), petroleum hydrocarbons (PHC), volatile organic compounds (VOC), and PAH concentrations. The analytical results of biosolids samples were evaluated using O. Reg. 38/09 (amending O. Reg. 267/03) to assess land application suitability. Analytical results are provided in the MTE Report (2012). It should be noted that all materials are suitable for disposal at a conventional landfill, subject to meeting slump test regulations.

1.8.2.4.2 Lagoon 1

Analytical results included moisture content percent in two biosolids samples and the results were converted to % solids. The Lagoon 1 biosolids were 18 % (w/w) solids, on average. A summary of the parameters that exceeded O. Reg. 338/09 and/or O. Reg. 153/04 (as amended) is included in Table 4 and Table 5 for biosolids and the clay liner, respectively. Table 4 Summary of Biosolids Exceedances in Lagoon 1

Metals Unit O. Reg. 338/09

Schedule 5 Table 1- CM1 NASM

O. Reg. 338/09 Schedule 5 Table 2- CM2 NASM

21-Nov-11(1) LAGOON 1 -A

Dense Biosolids LAGOON 1 -B

Dense Biosolids Cadmium (Cd) µg/g 3 34 6.30 6.61 Chromium (Cr) µg/g 210 2,800 215 447 Copper (Cu) µg/g 100 1,700 847 777 Mercury (Hg) µg/g 0.8 11 0.719 4.60

Molybdenum (Mo) µg/g 5 94 7.8 8.5 Nickel (Ni) µg/g 62 420 74.4 129

Selenium (Se) µg/g 2 34 2.7 3.1 Zinc (Zn) µg/g 500 4,200 884 1410

Note: Biosolids results are compared to O. Reg. 338/09 standards (as indicated in the table above). Bold result indicates concentration exceeding Table 1- CM1 NASM (Category 1 NASM) (1) Date sampled

Table 5 Summary of Clay Liner Exceedances in Lagoon 1

Metals Unit MOE Table 2 SCS 21-Nov-11(1)

LAGOON 1-B Liner

LAGOON 1-B Liner

Cadmium (Cd) µg/g 1.9 2.7 3.56 Chromium (Cr) µg/g 160 292 328

Note: Clay liner results are compared to O. Reg. 153/04 (as amended) Table 2 SCS. Bold result indicates concentration exceed applicable MOE standard. (1) Date sampled

O. Reg. 338/09, Schedule 5, Regulated Metal Content of Non-Agricultural Source Materials (NASM), Table 1-CM1 NASM and Table 2-CM2 NASM indicate two quality categories for metals (CM1 and CM2). Note that according to the Environmental Commissioner of Ontario (Redefining Conservation, Annual Report Supplement 2009/2010); the CM1 criteria are the same as those being proposed for Ontario “AA” quality finished compost. The CM2 criteria are the same as those currently used for approving Organic Soil Conditioning Site C of A for sewage biosolids.

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Analytical results for biosolids samples at Lagoon 1 detected exceedances of O. Reg. 338/09 Table 1- CM1- NASM, Column 3 for Cd, chromium (Cr), Cu, Pb, Hg (Lagoon 1-B only), Mo, Ni, Se and Zn. No exceedances for O. Reg. 338/09 Table 2- CM2- NASM were detected in Lagoon 1. Based on the exceedances detected in biosolids samples in Lagoon 1, the biosolids are not considered to be suitable for land application under Table 1- CM1 NASM for O. Reg. 338/09, but are suitable to be applied to an approved land application Site under Table 2- CM1 NASM criteria. Several organic compounds were also detected in the dense biosolids in Lagoon 1, including dichlorodifluoromethane, PHC parameters (F1 to F4 fractions), benzo(a)pyrene, and PCB; however, there are no criteria listed under O. Reg. 338/09 for these parameters. The analytical data from samples collected from the Lagoon 1 clay liner indicated exceedances of MOE Table 2 Site Condition Standards (SCS) for Cd and Cr. The analytical results for VOC, PHC, PAH and PCB parameters were slightly above the laboratory reportable detection limit (RDL) but well below the MOE Table 2 SCS. It is important to note that only two (2) locations were sampled during the investigations completed by MTE in late 2011; therefore, the results are considered to be a preliminary assessment. Additional investigations will be required to provide a more robust characterization of the biosolids and clay liner with respect to land application suitability and the nature and extent of contamination.

1.8.2.4.3 Lagoon 2

A total of eight (8) sampling locations were completed at Lagoon 2 and nine (9) biosolids (including one duplicate) and nine (9) clay liner (including one duplicate) samples were collected for analysis. Analytical results included moisture content percent in eight samples and the results were converted to percent solids. The average of the results indicated 10% solids are present in the biosolids in Lagoon 2. A summary of the parameters that exceeded O. Reg. 338/09 and O. Reg. 153/04 (as amended) are provided in Table 6 and Table 7 for biosolids and the clay liner, respectively. Biosolids sample results were evaluated using Schedule 5, Table 1 CM1 NASM and Table 2 NASM criteria provided in O. Reg. 338/09. Exceedances of the Table 1 CM1 NASM criteria were detected for Cd, Cu, Hg, Mo, Ni, Se, and Zn in one or more of the sample locations, as summarized on Table 6 . There were no exceedances of the O. Reg. 338/09 Table 2 - CM2 NASM criteria for any of the biosolids samples analyzed from Lagoon 2. Based on the exceedances detected in biosolids samples collected from Lagoon 2, the biosolids are not suitable for land application under Table 1 –CM1 NASM for O. Reg. 338/09. However, there were no exceedances to the O. Reg. 338/09 Table 2-CM2 NASM criteria, therefore biosolids may be land applied to an approved property under Table 2-CM2. It should be noted that elevated concentrations of PHC (F2-F4), PAH [benzo(a)pyrene, indeno(1,2,3-cd)pyrene] and PCB were detected in several biosolids samples in Lagoon 2, however, there are no standards under O.Reg.338/09 for these parameters. The analytical results for samples collected and analyzed from the Lagoon 2 clay liner were lower than the biosolids samples; however, exceedances of the MOE Table 2 SCS for Cd, Cr, and Zn were detected in one or more samples as summarized in Table 7. The analytical results for VOC, PHC, PAH and PCB were below the MOE Table 2 SCS or marginally above the laboratory RDL.

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AECOM Regional Municipality of Waterloo Kitchener WWTP Upgrades Preliminary Design DRAFT Final Report


1.8.2.4.4 Soil and Groundwater Results from Monitoring Well Locations

A total of eight (8) groundwater monitoring wells were installed on the lagoon berms and perimeter of the lagoons. A total of 18 soil samples (including two duplicates) were collected for analysis to measure metal, PCB, PAH, PHC and VOC concentrations and select samples were submitted to determine grain size, fraction of organic carbon (foc), general chemistry and cation exchange capacity (CEC). Eight (8) groundwater samples (one from each monitoring well) were collected to measure general water quality parameters (pH, conductivity, anions, and nutrients), E. coli, PHC, VOC, and PAH concentrations. Note that some of the analytes for soil and groundwater had RDLs above the applicable MOE standards, which precluded the ability to assess the presence or absence of impact for those parameters. Based on MTE’s soil borehole logs and grain size/hydrometer analysis performed on select soil samples from each borehole, the soil from the berms and around the lagoons contained fill materials from the ground surface to depths ranging from approximately 3.0 m (MW8-11) to 7.4 m (MW6-11) mbgs [278.1 to 275.5 m above sea level (mASL)]. The fill materials consisted mainly of silty sand with varying proportions of gravel. These fill materials were underlain by a heterogeneous mixture of clay, sand and gravel from approximately 3.0 mbgs to 11.3 mbgs (278.1 to 271.9 mASL), the maximum depth of borehole penetration. According to the MTE Report (2012), saturated soil conditions were noted at all the monitoring well locations following drilling activities at depths that ranged from 3.0 (MW8-11) to 7.7 mbgs (MW4-11) (278.1 to 275.5 mASL). The borehole logs, grain size analysis and hydrometer analysis are provided in the MTE Report (2012). Soil and groundwater sample results from the monitoring well installation program were evaluated using current applicable MOE generic SCS. Soil and groundwater samples collected from boreholes and wells located within 30 m of the Grand River (i.e., MW2-11 and MW3-11) were evaluated using the MOE Table 8 SCS, and all other soil and groundwater samples collected from the monitoring well locations wells were evaluated using the MOE Table 2 SCS. Soil samples that exceeded the MOE Table 2 and/or MOE Table 8 SCS are summarized in Table 8 below. Exceedances of the applicable MOE Table 8 SCS were detected in a sample from MW2-11 at a depth of 4.6 m to 5.2 mbgs for Cd, Cr, Cu, Hg, and Zn. In a soil sample from MW1-11, exceedances of the MOE Table 2 SCS were detected at a depth of 4.6 to 5.2 mbgs for several parameters including metals, VOC, PAH, PHC and PCB. All remaining soil sample results (16 samples, including duplicates) were below applicable MOE SCS. A total of eight (8) groundwater samples were collected for analysis during the program. Groundwater sample analytical results indicated that exceedances were detected in samples collected from wells MW7-11 and MW8-11 as summarized in Table 9. Benzo(a)pyrene marginally exceeded the MOE Table 2 SCS (0.01 g/L) in a samples collected from wells MW7-11 (0.036 g/L) and MW8-11 (0.037 g/L). This low level benzo(a)pyrene concentration may be indicative of the presence of sediment in the sample. Chloride was measured at a concentration of 1,440 mg/L was also detected above the MOE Table 2 SCS in a sample collected from well MW8-11.



Table 8 Summary of Soil Analytical Parameters Exceeding Guidelines

Analytical Parameter Units MOE

Table 8 SCS

25-Nov-11(1) MOE Table

2 SCS

28-Nov-11(1)

MW2-11 (15-17)(2)

MW2-11 (27.5-29.5)(2)

MW2-11D (27.5-29.5)(2)

MW1-11 (15-17’)(2)

MW1-11 (27.5-

29.5’)(2)

Metals

Cadmium (Cd) µg/g 1.2 17.1 <0.50 <0.50 1.9 38 <0.50

Chromium (Cr) µg/g 70 1240 9.5 10.4 160 2730 11.8

Copper (Cu) µg/g 92 101 7.6 6.9 230 248 9.5

Lead (Pb) µg/g 120 64.3 3.1 3.5 120 152 10.8

Mercury (Hg) µg/g 0.27 0.703 <0.010 <0.010 20 1.74 <0.010

Zinc (Zn) µg/g 290 300 15.8 17.1 340 648 66.6

VOC Acetone µg/g 0.5 0.80 <0.50 <0.50 28 1 <0.50

PHC F3 (C16-C34) µg/g 240 <50 <50 <50 2500 4150 <50

PAH Acenaphthylene µg/g 0.093 0.076 <0.050 <0.050 0.17 0.368 <0.050

Benzo(a)pyrene µg/g 0.3 0.073 <0.050 <0.050 0.3 0.718 <0.050

Dibenzo(ah)anthracene µg/g 0.1 <0.050 <0.050 <0.050 0.1 0.118 <0.050

PCB Total PCBs µg/g 0.3 0.399 <0.020 <0.020 1.1 2.77 <0.020

Note: BOLD result indicates concentration exceeding O. Reg. 153/04 (as amended), Table 2 or Table 8 SCS. (1) Date sampled (2) Depth in feet.

Table 9 Summary of Groundwater Analytical Parameters Exceeding Guideline

Analytical Parameter Units MOE Table 2 SCS 14-Dec-11(1) MW7-11 MW8-11

Chloride mg/L 790 150 1440 Benzo(a)pyrene g/L 0.01 0.036 0.037

Note: BOLD result indicates concentration exceeding O. Reg. 154/03 (as amended), Table 2 SCS. (1) Date sampled

Measured groundwater concentrations for all other parameters from all monitoring well locations were below the applicable MOE SCS. The findings of the groundwater assessment indicate that there are low level benzo(a)pyrene exceedances in two (2) of eight (8) wells installed during the program. These wells will be re-sampled to confirm the initial findings. Following the installation of each monitoring well, hydrogeological testing was completed to determine the hydraulic conductivity of the shallow overburden aquifer underlying the Site. Hydraulic conductivity results ranged from 8.51 x 10-5 m/s (at MW1-11) to 3.25 x 10-7 m/s (at MW8-11), and the average hydraulic conductivity was 3.25 x 10-7 m/s. Hydraulic conductivities are considered to be representative of the screened intervals in the soils reported in the MTE Report (2012).

1.8.2.4.5 Data Gap Analysis

Based on the MTE subsurface investigation results (MTE, 2012), several areas within and adjacent to the lagoons require additional assessment to confirm and further delineate the extent of impacts. The following supplemental investigation program is proposed to address the identified data gaps: Additional data are required to conduct a screening level ecological risk assessment to assess potential

ecological risk to the Grand River from contaminants in the clay liner and soil in the berms surrounding the lagoons;

Delineation of contaminated soil within selected areas of the Lagoon 1 north and northwest berms; Delineation of contaminated clay liner in Lagoon 1 and portion of Lagoon 2; and



Re-sampling and analysis of select groundwater monitoring wells to confirm initial findings. This work will be performed as part of Detailed Design.

1.8.3 Underground Utilities Locates

The existing Kitchener WWTP has an extensive network of buried utilities including medium voltage power (600 V) for process equipment, low voltage power for building services, phone and communications lines, natural gas, digester gas, potable water, effluent water and process piping. The new works will require that new utilities, including high voltage power lines (13,000 V), be constructed within the same corridors. AECOM prepared a Terms of Reference and solicited bids on behalf of the Region to conduct an underground utilities location survey. The preliminary underground utilities location survey was conducted by Terra Discovery. A preliminary site locates drawing was prepared and issued for review. Due to the complexity and extent of buried services, the drawing provides a good overview but is considered to be incomplete. Additional investigative work will be required for each specific Contract to confirm exact locations and elevations of buried piping. OCWA staff should be available to assist with the detailed surveys to provide historical information and to clarify apparent conflicts.

1.8.4 Hydraulic Transient Analysis

The Kitchener WWTP currently pumps digested sludge from the plant site to the Manitou WWRMC for dewatering and offsite disposal. As part of the Lagoon Decommissioning Contract, the existing booster pumping station will be decommissioned. New booster pumps will be installed within the existing Administration Building. Given the force main length, complexity and nature of the sludge to be pumped, an updated hydraulic transient analysis was completed for the new sludge pumping station Preliminary Design (AECOM, 2012a). The analysis was updated for forward flow analysis for a flow range of 80 to 100 L/s. Reverse flow analysis and the centrate pumping station and force main were assessed in the previous report. The following are objectives of the transient analysis: Conduct steady state and transient analysis for the proposed pumping station and existing force main Assess the system for three conditions:

o Existing with 1 to 2 % solids o Additional thickening (2020) with 2 to 3% solids o Further thickening (2030) with 3 to 4% solids

Develop system head curves based on the steady state analysis Confirm transient response to both normal operation and worst case transient events Assess existing transient protection and define further protection requirements

The analysis was completed for the Preliminary Design and provided the general type, location and sizing of transient protection requirements. The analysis will be finalized in conjunction with equipment selection during detailed design. The following were general recommendations made for the system in the hydraulic analysis: Sludge parameters were assumed based on the reported solids content and accepted design guidelines.

However, due to the force main length, we recommend that the Region conduct verification testing on the sludge to confirm its characteristics as the standard methodology used in only intended for sludge force mains that are less than or equal to 1.6 km in length



We recommend that the Region conduct flow and pressure measurements for the sludge force main in order to validate the modeling results and conduct high frequency transient pressure monitoring (such as TP1 monitors) of the existing pumps to verify the transient model outputs

The exact profile of the force main between the pumping station and the junction chamber was not available and should be confirmed for the detailed design analysis

The high density polyethylene (HDPE) force main within the abandoned sewer should be inspected for structural integrity and ovality and support straps maintained or replaced as necessary

The surge protection equipment for wastewater systems requires vigilant maintenance, in order to ensure their continued reliable performance

Pipeline filling and draining should be done slowly, with a velocity no more than 0.3 m/s The pumping station and yard piping layout should minimize horizontal and vertical bends to reduce friction

losses

1.8.5 Site Wide Facility Plan

The Site Wide Facility Plan (AECOM, 2011) defined the processes, systems and equipment required for an upgraded Kitchener WWTP that can reliably meet performance objectives for flow up to the plant capacity. The Site Wide Facility Plan is being used as the basis to move from planning to design and construction of the proposed works over a period of approximately 10 years. The Site Wide Facility Plan presented the key findings of a series of technical memoranda (TMs) developed during the Site Wide Facility Plan process. The series of TMs were prepared to summarize the information, present the evaluation process and document the decision making process leading to the selection of a preferred approach. As part of the project, a series and workshops were conducted on specific aspects of the Site Wide Facility Plan. An Expert Panel participated in the workshops to provide independent review of the evaluation and recommendations. Table 10 lists the TMs that were prepared during the Site Wide Facility Plan process. The information originally anticipated for TM-7 was incorporated into other memoranda and TM-7 was not prepared as a stand-alone document. Table 10 Technical Memoranda Prepared During Site Wide Facility Plan Process

TM Title

1 Physical Condition Status

2 Process Capacity Assessment and Base Models

3 Description of Study Area, Considerations, and Constraints

4 Flow, Loading, and Treatment Criteria and Regulatory Framework

5 Project Goal Statement and Sustainability Evaluation Approach

6 Review of Lagoon Decommissioning Approaches and Investigative Needs

8 Headworks Options

9 Secondary/Tertiary Treatment Process Options

10 Power Supply and Standby Power Options

11 Digestion and Energy Recovery Options

12 Options for Addressing Plant Deficiencies

13 Thickening Building Design Concept

14 Site Layout and Construction Phasing



1.9 Site Layout

An overall site plan (000-C102) in Appendix A shows the proposed layout for the Kitchener WWTP following completion of the recommended plant upgrades. The new Headworks Facility (screening, grit removal and chemical dosing) will be constructed within the space between the plant entrance and existing Lagoon 1 just to the southeast of the existing Headworks Facility in order to minimize the required channel modifications and associated headloss. A new flow splitter chamber will be constructed adjacent to the primary clarifier effluent channel to provide an equal flow split (under normal conditions) to Plants 2, 3 and 4. The Plant 3 and 4 aeration tanks and secondary clarifiers will be constructed within the existing Lagoon 1 footprint. A new conduit will carry secondary effluent from Plants 3 and 4 to the new Tertiary Treatment Building located to the southeast of the UV Disinfection Building currently under construction. The conduit will pick up secondary effluent from Plant 2 Secondary Clarifiers No. 2 and 3. Tertiary effluent will discharge to the influent of the UV Disinfection Building (currently under construction). A new RAS/WAS pumping station for Plant 2 will be constructed on the site of the existing RAS/WAS pumping station, which will be decommissioned. The existing Digestion Facilities on the west corner of the site will undergo significant modifications. A new digested sludge pumping system and force main will be constructed to pump stabilized sludge to the existing WWRMC force main. The new Energy Centre will be constructed to the east of the existing Digestion Facilities. The new electrical service and co-generation building (not included in the Phase 3 Upgrades) will be located just to the south of the Energy Centre. The new Thickening Building will be attached to the east of the Energy Centre Building. The site layout has taken into consideration the potential requirements to accommodate an ultimate expansion (beyond 50 years) to 140 MLD. The Headworks Building has been sized with sufficient space to accommodate the increase in flow. A new primary clarifier may be required, which could potentially be constructed within the space currently occupied by Plant 1, which will have been decommissioned by that time. Additional aeration tanks and secondary clarifiers would be required. These can also be constructed within the space currently occupied by Plant 1. All other new structures will be sized to accommodate the future increase in flows.

1.10 Approvals

Several applications for approvals and permits will be required in order to proceed with construction. Table 11 presents approvals and permits that will be required, as well as estimated timing for each. It is noted that certain activities will have special approval requirements and these have also been noted. Table 11 Permit and Approval Requirements for Construction

Permit or Approval Typical Time Required and Estimated Time to Apply

Ministry of the Environment (MOE), Amended Certificate of Approval (C of A) (Sewage) / Environmental Compliance Authorization (ECA)

C of A process was replaced late 2011 with Environmental Compliance Authorization (ECA) process. The Region is engaging with the MOE to have a conditional amendment of the C of A for the entire project, with each individual project reviewed at the time of tendering. Pre-consultation stated during Site Wide Facility Plan and is ongoing.

Due to timing of Lagoon decommissioning and sludge pumping, a stand-alone amendment for these two elements should be applied for 6 months before the planned start of construction.

Ministry of the Environment (MOE), Amended Certificate of Approval (Air and Noise)

Air approvals now handled in similar fashion to sewage (above), but the approvals time is longer. Apply 6 to 12 months before planned start of construction .

Technical Standards and Safety 2 months, middle of detailed design (applies to various contracts)



Permit or Approval Typical Time Required and Estimated Time to Apply

Association (TSSA)

City of Kitchener Building Permit 1 month, following Site Plan Approval (applies to all contracts) Demolition permit will be required for Lagoon Decommissioning project.

City of Kitchener Site Plan Approval 6 to 8 months, schedule meeting middle of detailed design (applies to all contracts) May need separate approval for Lagoon Decommissioning Contract Will be required for access road improvements

Utilities With site plan approval

Ministry of Labour (MOL) notification To be determined, based on contract administration and potential for multiple simultaneous contracts Preliminary consultation has taken place Application and meeting with MOL 6 Months prior to first main contract (Contract 2)

ESA reviews: High Voltage Low Voltage

Review time frames vary from 4 to 8 weeks, end of detailed design

Grand River Conservation Authority (GRCA) Application for Development, Interference with Wetlands and Alterations to Shorelines and Watercourses Permit

Pre-consultation taking place through Steering Committee meetings and separate meetings (e.g., Feb 24, 2012)

2 to 3 months for most contracts, in consultation with GRCA throughout detailed design, permit in conjunction with Site Plan Approval; longer approval time for outfall.

Minimum 1 year for outfall due to need for co-ordination with DFO and ecological studies Ecological investigations to be based on 3 season data collection and to cover all areas to be disrupted by construction including existing swales and drainage systems.

Permit to capture berm removal and regrading Impacts from outfall construction method (i.e., coffer dam) to be addressed in application’s supporting material and to include HEC-RAS modeling related to coffer dams in water

Assess whether coffer dam or wet crossing is preferred for outfall construction MOE Permit-To-Take-Water (PTTW) 3 months, end of detailed design (e.g., lagoon decommissioning)

Will be required for most Contracts. As part of the application, supporting material will be required, such as a review of the local and regional hydrogeological conditions, pumping tests and calculations to determine the water taking requirements for the project. All materials will be submitted in accordance with Category 3, under Section 34 of the Ontario Water Resources Act. A PTTW plan was submitted and approved for the UV Disinfection Effluent Pumping Station project and this should be used as a basis for the Phase 3 works.

Normally, Category 3 permit has to be renewed annually.

Department of Fisheries and Oceans (DFO), HADD Authorization or Letter of Advice, Species At Risk Act (SARA) Permit

Initiate in conjunction with GRCA permit and approval process Typically 1 year process DFO/GRCA will need to review comprehensive fisheries assessment at site (including habitat characteristics and fish community). Assessment of Impacts and Mitigation for ideally no Harmful Alteration Disruption Destruction (HADD) of fish habitat. Initial review completed by GRCA. DFO will review if HADD is likely. Compensation required if so.

HADD determination will trigger CEAA Screening. (Review alongside other triggers such as Transport Canada NWA).

Ministry of Natural Resources (MNR), Endangered Species Act Permit and Application for Work Permit (Crown Land Management)

Initiate in conjunction with GRCA permit and approval process Typically 1 year process, should an endangered or threatened species be affected by the project – applies to outfall only

New Information Gathering Forms to determine the need for species inventories must be filled out prior to consultation with MNR

Specific methodology for species survey to be followed-looking at species at risk habitat features, visual species sighting and habitat use supported by mapping.

Ministry of Tourism and Culture (MTC) Archaeological Clearance

Assume MTC will determine that a Stage 1 Archaeological Assessment is required. 3 to 4 month process. Add to mailing list, complete MTC archaeological resource checklist, submit with PIC #2 Notice



2. Existing Facility Assessment A detailed overview of the existing Kitchener WWTP is presented in the final Site Wide Facility Plan Report (AECOM, 2011), key details from which are presented in this section.

2.1 Site Details

The Kitchener WWTP is located at 368 Mill Park Drive in the City of Kitchener. The plant site is surrounded by residential land uses and open space. The Grand River borders the plant on the north, east, and west sides.

2.1.1 Environmental Features, Surface Waters and Flood Plain Mapping

The City of Kitchener lies within the Grand River Watershed and the Kitchener WWTP site itself lies in the flood plain of the Grand River. Figure 2 shows the Grand River flood plain in the vicinity of the Kitchener WWTP site.

Figure 2 Kitchener WWTP Flood Plain Mapping



Due to the proximity of the plant site to the Grand River, the GRCA is responsible for ensuring construction at the site does not interfere with the shoreline or watercourse, as regulated through O. Reg. 97/04, the Development, Interference with Wetlands and Alteration to Shorelines and Watercourses Regulation, under the Conservation Authority Act. O. Reg. 97/04 allows conservation authorities to prevent or restrict development in areas where the control of flooding, erosion, dynamic beaches, pollution or the conservation of land may be affected by development, in order to prevent the creation of new hazards or the aggravation of existing hazards. If it can be demonstrated to the satisfaction of the conservation authority that the proposed work will not affect the control of flooding, erosion, dynamic beaches, pollution or the conservation of land, a conservation authority may grant permission for the proposed work. All work must receive approval from the GRCA through a permitting process.

2.1.2 Available Space

The Kitchener WWTP has limited space on site for the Phase 3 construction. Construction within the floodplain cannot be avoided and special design considerations are required to flood-proof all new structures and minimize impacts on the floodplain itself. The largest open space available is the area currently occupied by the existing sludge lagoons. There are also some smaller areas available, including the area to the north and north east of the digesters (in the vicinity of the existing chlorine contact chamber), and to the west of the Plant 2 secondary clarifiers (adjacent to the UV disinfection facility currently under construction). Construction within the existing sludge lagoons would minimize any new impacts on the floodplain. Therefore, decommissioning of the existing sludge lagoons and preparation of the land is required for construction of the largest components of the Phase 3 facilities.

2.1.3 Existing Wastewater Residuals Management Centre

The WWRMC is located at 440 Manitou Drive in the City of Kitchener. Coordination with the WWRMC is required for digested sludge pumping to the WWRMC and for the return of the centrate to the Kitchener WWTP for treatment.

2.1.4 Site Constraints

The Kitchener WWTP site has several constraints that were considered in developing the Site Wide Facility Plan and Preliminary Design. Some of these considerations include: The plant is located in the Grand River flood plain. Plant access is via a steep entrance road, which can cause access issues for large trucks and deliveries during

winter months and may be strained to handle the large volume of construction traffic. Access to the plant site is restricted to a designated truck route to the south of the plant. The Kitchener WWTP site is fairly constrained and has limited site area available for future plant processes. Soil conditions on site are known to be difficult for construction and therefore foundation support for certain new

structures and buildings will be required. Due to congested connections to existing facilities, caution will need to be exercised to ensure that interruptions

to existing operations and processes are minimized during construction. Continued use of Plant 1 will be required until sufficient capacity is available following construction of Plant 3 and

4 and the construction of the Plant 2 RAS/WAS pumping station. Interim Plant 1 aeration upgrades were implemented to ensure reliable plant operation.

All works must be constructed taking into consideration the need to protect the works from flooding during high water levels in the Grand River. Any new structures should be flood-proofed up to at least the design flood elevation of 282.37 m, and if practical, designed to the regional flood elevation of 283.63 m. To meet these requirements, all building entrances and critical equipment and services will be located above these elevations.



2.2 Baseline Treatment Processes

Figure 3 presents a process flow schematic of the baseline WWTP, as of the year 2013. This process flow represents the baseline condition with all ongoing upgrades (i.e., Phase 1 and 2 upgrades) completed prior to commissioning of the Phase 3 works. Wastewater flows by gravity to the plant, where it receives preliminary treatment through screens and detritors. Primary treatment is provided in four rectangular clarifiers equipped with travelling bridge sludge scrapers. Primary effluent is split, between two (2) parallel secondary activated sludge plants, referred to as Plant 1 and Plant 2, each including aeration tanks and four (4) circular secondary clarifiers. Iron salts can be added upstream of primary treatment and/or to the secondary treatment process for phosphorus precipitation. Waste activated sludge (WAS) is returned to the primary clarifiers for co-settling.

Figure 3 Process Flow Schematic for Baseline Kitchener WWTP

Secondary effluent will be disinfected in a UV process and discharged to the Grand River. An effluent pumping station will be used occasionally, based on incoming sewage flows and the level in the Grand River. Co-thickened sludge will be anaerobically digested in two (2) parallel primary digesters and two (2) secondary digesters (only 1 active). Digested sludge will be pumped to the WWRMC to be dewatered and hauled off-site for disposal. All centrate from the WWRMC will be directed to Plant 2. TM-1, included in the appendices of the Site Wide Facility Plan (AECOM, 2011), provides a detailed description of the existing facilities and their condition.

2.2.1 Preliminary Treatment

The influent channel and the headworks were constructed in 1977 as a part of a second expansion to the Kitchener WWTP. The inlet channel is an aqueduct that feeds the Headworks Building. This structure is partially constructed of

Screens Detritors Primary Clarifiers

RawWastewater

UV Channels

Discharge To Grand River

Co-thickening WAS

Primary Sludge

Off-Site BiosolidsManagement

Secondary Clarifiers

Aeration Tanks

Secondary Clarifiers

Plant 1

Plant 2

AnoxicZone

EffluentPumping Station

Return Activated Sludge (RAS)

Co-thickening WAS

PrimaryDigesters

Wastewater Residuals

Management Centre

Iron Salt Addition

Secondary Digesters

Iron Salt Addition

Iron Salt AdditionStandby Chlorine

Contactors

RASReaeration

Aeration Tanks

Dewatering Centrate

Year 2013 – Includes Plant 2 Upgrade



a covered pre-cast channel supported on steel piles, and the curved sections are cast in place concrete channels supported on concrete piers. The Headworks Building is an enclosed two-storey concrete building located east of the primary clarifiers. The building includes a screen room equipped with three (3) mechanically cleaned screens. The screens have reached the end of their life expectancy and the wide bar spacing results in excessive materials passing through and causing maintenance/performance issues in the aeration tanks and digesters. Grit removal is accomplished in two (2) detritors, each 10.7 meters2, which allow for passive settling of heavy materials. Detritors are no longer installed in Ontario WWTPs. Screenings and grit are transferred to bins located under the detritors and hauled off-site for landfill disposal. The chemical system is also attached to the Headworks Building. The system consists of three (3) outdoor chemical storage tanks, two (2) containing ferric chloride and one (1) containing ferrous chloride. Included in the system are pumps that allow the iron salt to be added either at the head of the primary clarifiers or at the beginning of the second pass and end of the third pass of the aeration tanks for phosphorus removal.

2.2.2 Primary Treatment

The primary clarifier tanks are located in the south-central area of the treatment plant. The structure was built in 1977 as a part of a second expansion to the treatment facility, and consists of four (4) half buried, open, rectangular concrete tanks. Details of the primary clarifiers are provided in Table 12. The four rectangular primary tanks equipped with travelling bridge sludge scrapers provide a total surface area of 4,584 m2. Each primary tank has four (4) sludge hoppers. Normally, approximately 30% of the primary effluent is fed to Plant 1 and 60% to Plant 2; however, flexibility exists to modify stop log positions in the primary effluent channel to adjust flow distribution to secondary treatment. A secondary bypass weir is available to direct flow around secondary treatment directly to disinfection. Table 12 Description of Primary Clarifiers

Parameter Value

Number of units 4

Surface area per unit (19.8 m wide X 57.9 m long) 1,146 m2

Total surface area 4,584 m2

Average water depth 3.6 m

Total volume 16,777 m3

The primary sludge pumping gallery is a closed one (1) storey concrete structure that is a part of the primary clarifier building. The co-settled sludge is pumped to the primary digesters for stabilization.

2.2.3 Secondary Treatment

The Kitchener WWTP contains two (2) activated sludge plants. Plant 1, originally constructed in the 1960s, includes four parallel aeration tanks, each consisting of 7 cells in series. The old, unreliable mechanical surface aerators were recently replaced with blowers and fine bubble aeration system to ensure the plant’s reliability through to the end of the Phase 3 upgrades when Plant 1 will be decommissioned. This plant was designed as a step feed high rate activated sludge plant, but is currently operated in plug flow mode with the feed entering the head of each of the four aeration tanks. Plant 1 includes four circular secondary clarifiers. The Plant 1 blowers will ultimately be relocated to Plant 3 and 4 when no longer required for Plant 1.



The Plant 2 aeration tanks were constructed in 1977 and consist of two (2) tanks, each with four (4) cells (for a total of 8 cells), each with a mechanical aerator, electrical motor and gearbox. The primary effluent is distributed to the tanks through a division chamber, which splits the flow to two (2) distribution chambers, with isolation sluice gates to each cell. The aeration tank effluent is collected through adjustable weirs (two per cell) by a perimeter channel and is conveyed to the secondary clarifiers. Once the current upgrades to Plant 2 are complete, the Plant 2 aeration tank will be a three (3) pass plug-flow tank equipped with fine bubble diffused aeration. The first cell in the tank will be a RAS reaeration zone, where RAS will mix with centrate. The primary effluent is added after the RAS reaeration zone. The next cell can be operated in either aerobic or anoxic mode; the intent is to operate as an anoxic selector to recover alkalinity. The remainder of the tank is a plug-flow aerated zone. The Plant 2 secondary clarifiers consist of four (4) buried, open circular concrete tanks. The process equipment associated with the Plant 2 secondary clarifiers consists of flow measurement, manual sluice gates at the influent distribution chamber, WAS collection chamber, and a scraping mechanism for sludge/scum collection (one in each secondary clarifier). The Plant 2 RAS/WAS pumping station is a two (2) storey enclosed structure with exterior concrete walls forming the troughs for the RAS/WAS screw pumps. The Plant 2 RAS/WAS pumping station is equipped with two (2) inclined screw pumps and associated piping and valves, and instruments and controls. The pumps draw WAS/RAS from a wet-well. The RAS is returned to the aeration tanks while the WAS is pumped to the four common primary clarifiers, where it is co-thickened with the primary sludge. The WAS and RAS flows are controlled manually based on the flow meter readings. A description of Plant 1 and 2 processes is provided in Table 13. Table 13 Description of Secondary Treatment Processes

Process Parameter Plant 11 Plant 23

Aeration tanks Number of parallel tanks 4 1

Process configuration Plug flow with 7 cells in series in each tank

3-pass plug flow with RAS reaeration and anoxic cells in first pass

Volume 17,840 m3 (4,676 m3 per tank) RAS reaeration: 3,768 m3 Anoxic: 1,882 m3 Aerobic: 13,742 m3 Total: 19,392 m3

Depth 3.8 m 4.8 m

Aeration Equipment

Description Fine bubble diffuser system, tapered according to configuration1

Fine bubble diffuser system, tapered according to configuration

Estimated oxygen transfer capacity (SOTR)

1,920 kg O2/h2 2,320 kg O2/h3

Secondary clarifiers

Number of clarifiers 4 4

Type Circular Circular

Surface Area 1,869 m2 (467.2 m2 per tank) 3,532 m2 (883 per tank) Notes: 1. Based on the on-going interim improvements to the Plant 1 aeration system. 2. From Kitchener WWTP Plant 1 upgrade aeration system specifications 3. From Kitchener WWTP Plant 2 upgrade specifications (CH2M HILL, September 2010).



2.2.4 Anaerobic Digestion Facility and Sludge Holding Tanks

The Primary Digesters No. 1 and 2 (previously designated as No. 5 and 6), located in the south-west corner of the Kitchener WWTP, were built in the late 1970s as a part of the secondary expansion of the WWTP. The structures are three (3) storey cylindrical concrete tanks with conical metal roofs. The two (2) tanks are linked by a two (2) storey equipment building with a basement. The primary digesters’ equipment consists of a sludge transfer pump located in the basement, biogas sediment/condensate traps with flame arrester, and heating circulation pumps on the mezzanine, all with associated piping, valves, controls, etc. The primary digester heat exchangers and mixing equipment consists of a bubbler type system with an integral heat exchanger and with gas compressors installed in an enclosure at the top of the tank (close to the pressure relief valve with flame arrester enclosure), and the mixing guns located on the mid-circumference of the digester dome. The current mixing/heating system is ineffective. An interim mixing system is currently being installed in Digester 1 Secondary Digesters No. 3 and 4, located directly north of the primary digesters, were constructed prior to 1963. The two (2) cylindrical concrete tanks are two (2) storeys high; one digester has a gas tight floating roof while the other has a fixed roof vented to the atmosphere. The secondary digesters are regularly supernated to increase the solids content in the biosolids. The secondary digester equipment consists of sludge and biogas piping and manual valves, located in the ground level and basement of the central control room. The anaerobic digestion facility processes co-thickened sludge from the primary tanks. The sludge is pumped from the primary sludge pumping gallery to the primary digesters, and overflows from there to the secondary digesters. From the secondary digesters, the biosolids are pumped to the WWRMC. The abandoned digesters (formerly No. 1 and 2), used as temporary sludge holding tanks, are located to the south of the boiler building and their construction predates the earliest available record of construction in 1963. These tanks are circular buried structures, with steel bridges supporting equipment visible above ground. They are connected with a below grade pump chamber that is in turn connected to the boiler building by a service tunnel. The Technical Standards and Safety Authority (TSSA) conducted a digester inspection in April 2010. Deficiencies were identified in several areas including gas handling equipment, gas safety equipment, valves, ventilation, gas boosters, boilers, and signage. Addressing these code deficiencies is a high priority.

2.2.5 Boiler Building and Associated Facilities

The boiler building structure is a single storey masonry building with a concrete basement and a flat asphalt roof. The building was originally constructed prior to 1963, and was upgraded in 1963 as a part of the primary digestion expansion of the treatment facility and in 1977. In 1998, a new boiler building addition was constructed adjacent to the existing structure. The basement of this structure is connected to the former digesters/sludge tanks by a service tunnel, which also gives access to a boiler chamber that is below that access road to the west of the building. The boiler building basement houses the motor control centres (MCCs) with associated cable trays/conduits and the three (3) heating circulation pumps and piping, valves, etc. Other rooms in the basement house abandoned equipment (e.g., heat exchangers and pumps). A utility tunnel between the boiler building and the primary digesters accommodates hot water supply and return pipes, sludge piping, conduits, potable water, etc. The gas booster room includes three (3) gas boosters on the ground floor, a sediment trap (basement), and feeds the boilers in the adjacent room of the boiler building. All the equipment and services in the room are classified for Class 1 Group D.



The boiler room houses three (3) boilers and four (4) expansion tanks, installed in 1999 and 1977, respectively. The boilers run on biogas, with only one (1) boiler running at a time to provide the required heat for the digester heat exchangers and building heating.

2.2.6 Process Equipment in the Administration Building

The process equipment contained in the administration building consists of two (2) sludge transfer pumps (horizontal centrifugal pumps), and two (2) wet-well horizontal centrifugal pumps (transferring sanitary wastes from the administration building and digestion complex to the primary tanks). The sludge transfer pumps were installed in 1989 and in the mid 1990s. The heating circulation pump skid (including heat exchanger, expansion tanks and chemical addition system) was installed in 2005.

2.2.7 Chlorination

The chlorination building was built in 1963 as a part of the first expansion of the treatment facility. The chlorination building includes chemical storage tanks (sodium hypochlorite for disinfection and sodium bisulphite for de-chlorination) and chemical feed pumps with associated piping, valves and controls. RAS chlorination, to control sludge bulking, is practiced occasionally (dosed at the RAS/WAS pumping stations). The chlorination system will be decommissioned following the Phase 2 Upgrades (UV disinfection and effluent pumping station).

2.3 Baseline Greenhouse Gas Emissions

In keeping with the objective of minimizing the greenhouse gas footprint, a baseline model of existing greenhouse gas emissions was prepared. Table 14 presents a summary of the greenhouse gas emissions from the Kitchener WWTP under the baseline condition, based on 2013 projected flows. This model represents the baseline condition with all current upgrades completed but prior to commissioning of the Phase 3 works. Table 14 Preliminary Estimate of Greenhouse Emissions

Description Activity Data Emission Factor kg CO2e/year Scope 1: CO2, CH4 and N2O from fuel-combusting equipment (e.g., natural gas combusted in boilers) 31,897 m3/y 1890 g CO2e/m3 60,285

Scope 1: CH4 generated by digesters 1,511,465 kg/y 0.5 kg CO2e/kg CH4 761,778 Scope 1: N2O generated by biological processes 1,537,015 kg/y 0.97 kg CO2e/kg N 1,490,905 Scope 1: N2O generated in receiving water 433,620 kg/y 2.4 kg CO2e/kg N 1,040,688 Scope 2: CO2, CH4 and N2O from purchased electricity (e.g. electricity consumed by process air blowers) 8,376,000 kW•h/y 181 g CO2e/MW•h 1,516,056

Total 4,869,712

The greenhouse gas emissions model will be updated during the detailed design of the Phase 3 upgrades. It should be noted that, in order to implement the improved effluent objectives, especially year round complete nitrification, there will be an increase in energy consumption and consequently greenhouse gas emissions. The objective is to minimize the increase where possible.

2.4 Existing Certificate of Approval

The existing Amended C of A No. 8735-8HMJDH is dated June 9, 2011 and is attached as Appendix B. The C of A was amended to reflect the Plant 1 Upgrades and Phase 2 Upgrades currently under construction. The plant also has an amended Environmental Compliance Approval (ECA) (8735-8HMJDH, issued January 16, 2012) and an amended ECA (Air) (No. 3006-8NVPKU, issued March 30, 2012), which are included in Appendix B.



2.4.1 Plant Rated Capacity

Based on information provided in Certificate of Approval No. 8735-8HMJDH, the plant rated capacity is listed in Table 15. Table 15 Certificate of Approval Plant Rated Capacity

Treatment Train Average Daily Flow (m3/d) Peak Flow Rate (m3/d)

Plant 1 68,737 171,842

Plant 2 54,008 135,020

Total Plant Capacity 122,745 306,862

2.4.2 Plant Treatment Objectives and Non-Compliance Limits

Table 16 provides the current treatment objectives and non-compliance limits. Table 16 Existing Treatment Objective and Non-Compliance Limits

Effluent Parameter Treatment Objective Non-Compliance Limits

Concentration Objective Maximum Concentration Maximum Waste Loadings

cBOD5 15 mg/L 25 mg/L 3069 kg/d

Total Suspended Solids (TSS) 15 mg/L 25 mg/L 3069 kg/d

Total Phosphorus 0.6 mg/L 1.0 mg/L 123 kg/d

pH 6.0 - 8.5 6.0 - 9.5 -

E. Coli 100 org./100 mL N/A N/A



3. Overview This PDR is divided into 21 major sections. The PDR has been laid out generally in conformance with the Region of Waterloo Transportation and Environmental Services Wastewater Design Standard 52005 - Preliminary Design Report (Region of Waterloo, 2009). The following is an overview of the major sections of this PDR:

Section 1: Introduction provides background information, project approach and objectives, scope of work, overview of previous reports, description of plant layout and overview of approvals

Section 2: Existing Facility Assessment – Provides site details, overview of baseline treatment processes and greenhouse gas emissions and presents relevant details from the existing Certificate of Approval

Section 4: Design Criteria – Presents raw wastewater flows, wastewater characteristics and loadings, effluent criteria and sludge and biosolids generation rates

Section 5: Odour Management Plan – Provides an overview of the odour management plant Section 6: Evaluation of Upgrade Alternatives – Presents evaluation of upgrade alternatives for design

elements that deviate from the Site Wide Facility Plan Sections 7 - 16 each present details on process (including general description, design criteria, preliminary

design specifications, operating facility instrumentation and controls), architectural and structural, building mechanical, electrical, instrumentation and control, and construction sequencing, tie-ins and demolition (as applicable) for each process area included within the scope of the Kitchener WWTP Phase 3 upgrades:

o Section 7: Lagoon Decommissioning (Contract 1a) o Section 8: Digested Sludge Transfer Pumping (Contract 1b) o Section 9: Anaerobic Digestion (Contract 2b) o Section 10: Headworks (Contract 3a) o Section 11: Tertiary Filtration (Contract 3b) o Section 12: Outfall (Contract 3b) o Section 13: Secondary Treatment (Contract 4) o Section 14: Administration Building (Contract 5a) o Section 15: WAS Thickening (Contract 5b) o Section 16: Miscellaneous Improvements to Existing Facilities

Section 17: Electrical Design and Energy Centre (Contract 2a) – presents an overview of the existing electrical distribution system, general power distribution, distribution system upgrades, codes and standards, energy management plan, demand summary, standby power, cogeneration facility, construction contract considerations, lighting systems and SCADA.

Section 18: Common Elements – Provides details on elements that are common to all upgrade contracts, including: hydraulic profile, facility layout, piping, civil/site design, architectural and structural design, structural and geotechnical aspects, building mechanical design, and instrumentation and control design.

Section 19: Construction – Presents an overview of construction sequencing, tie-ins and demolition required for all contracts included in the Phase 3 Kitchener Upgrades

Section 20: Project Cost Estimate – Presents the cost summary, cost estimating basis/assumptions, and cash flow projections

Section 21: Value Engineering Decisions



4. Design Criteria 4.1 Raw Wastewater Flows

Process unit flows have been established based on historical flow data and MOE Design Guidelines. The rated average day flow will remain 122,745 m3/d. Plant conveyance systems will be designed to accommodate a peak instantaneous flow of 429,608 m3/d, based on a peak instantaneous flow factor of 3.5. The Kitchener WWTP raw sewage flow peak factors are presented in Table 17. Table 17 Kitchener WWTP Raw Wastewater Flow Peak Factors

Parameter Factor

Peak Instantaneous Factor 3.5

Peak Hourly Factor 2.5

Peak Day Factor 2.0

The design flows presented in Table 18 were used as the design basis for each process and were established using the appropriate peak factor for the specific process area. Notwithstanding the “rated design flows”, all process units have been designed to handle the instantaneous hydraulic flow, though at a possible loss of treatment effectiveness. Table 18 Design Flows

Process Maximum Rated Treatment Process Design Flow (m3/d) Peak Factor

Screening 429,608 3.5 (Peak Instantaneous)

Grit Removal 306,862 2.5 (Peak Hourly)

Primary Clarification 245,490 2.0 (Peak Day)

Secondary Biological Reactors 245,490 2.0 (Peak Day)

Secondary Clarifiers 306,862 2.5 (Peak Hourly)

Tertiary Treatment 306,862 2.5 (Peak Hourly)

Outfall 429,608 3.5 (Peak Instantaneous)

4.2 Wastewater Characteristics and Loadings

Based on historical data and supplemental sampling data, the design characterization and calculated loadings are provided in Table 19. Table 19 Raw Wastewater Characterization and Design Loading

Parameters Design Concentrations (mg/L) Design Average Loadings (kg/d)

BOD5 228 27,988

Soluble BOD5 82 10,066

COD 562 68,988

Soluble COD 119 14,608

TSS 257 31,548

VSS 223 27,374

TKN 43 5,278

Ammonia 27 3,314

TP 5.5 675

Soluble ortho-P 2.5 307

pH 7.5 (pH) -



4.3 Effluent Criteria

The anticipated effluent criteria are provided in Table 20. These criteria were developed in the Kitchener WWTP Upgrades, Middle Grand River Assimilative Capacity Report (Stantec, 2010) in conjunction with the GRCA and MOE and currently proposed as part of the ongoing EA being conducted for the Phase 3 plant upgrades. The expectation of the regulatory acceptability of these criteria is based on discussions with the MOE. Table 20 Anticipated Certificate of Approval Effluent Requirements

Effluent Parameter Treatment Objective Non-Compliance Limits

Concentration Objective Monthly Average Concentration2 Monthly Average Loading2

cBOD5 10 mg/L 15 mg/L 1,841 kg/d Total Suspended Solids (TSS) 10 mg/L 15 mg/L 1,841 kg/d

Total Ammonia-Nitrogen Non-freezing Period1 Freezing Period2

2 mg/L 5 mg/L

4 mg/L 7mg/L

492 kg/d 859 kg/d

Total Phosphorus 0.2 mg/L 0.4 mg/L 49 kg/d pH 6.0 - 8.5 6.0 - 9.5 - E. Coli3 100 org./100 mL 200 org./100 mL - Note: 1. Defined as when stream temperatures are greater than 5 oC, normally from May 2 to November 30 2. Defined as when stream temperatures are 5 oC or less 3. Measured as monthly geometric mean density

4.4 Sludge and Biosolids Generation Rates

The Region of Waterloo Biosolids Master Plan was completed as a separate project not specific to the Kitchener WWTP (CH2MHill, 2011). Consistent with the Master Plan, the continued use of anaerobic digestion at the Kitchener WWTP has been selected. A minimum of 15 days hydraulic retention time in the primary digesters to stabilize Kitchener WWTP sludge will be provided so that the product is suitable for either land application or landfilling. The sludge production quantities and quality at the plant design capacity are provided in Table 21. Table 21 Projected Sludge Production and Quality

Category Average Sludge

Produced (kg/day)

Peak Sludge Produced (kg/day)

VSS (% of TSS)

TSS Concentration (average)

Avg Sludge Flow 1 (m3/day)

Peak Sludge flow1

(m3/day)

Primary Sludge 18,698 26,232 77% 2 - 4% (3.1 % Average) 603 846

WAS (Plant 2) 6,894 9,674 74% 0. 5 - 1% 919 1,289

WAS (Plant 3 and 4) 13,996 19,641 74% 0.5 - 1% 1,866 2,618

Note: 1. Sludge flow at average TSS concentration



5. Odour Management Plan A number of background studies have been conducted by the Region to better understand and manage odours. These studies identified the following three key odour sources: Sludge storage lagoons Headworks facility Mechanical aerations systems

One objective of the Phase 3 Upgrades is to ensure that each of these three main sources of odours are managed to reduce the impact on the public. The Phase 3 Upgrades include sludge thickening facilities, which represent a new potential source of odours. The sludge storage lagoons will be decommissioned (removed from service) and the existing mechanical aerators in the aeration basins will be replaced with fine bubble aeration systems (both permanent on Plants 2, 3 & 4 and interim in Plant 1 until decommissioned). Odour management facilities will be provided for the new Headworks Building and Thickening Building.

5.1 Existing Conditions and Information

5.1.1 General Description

5.1.1.1 XCG Study (2007)

The Region retained XCG Consultants Limited (XCG) and Rowan Williams Davies & Irwin Inc (RWDI) to identify the sources of the odours experienced by local residents and investigate odour problems resulting from those sources. A report (XCG, 2007) was submitted to the Region. The report summarized work conducted during 2006 and 2007. Upon completion of a site survey and odour source investigation, computer modelling (using AERMOD) was used to assess the areas impacted by the odour sources in terms of frequencies and intensities. Several scenarios were investigated as indicated below: Scenario 1: All on-site sources of odour at the WWTP within the WWTP boundary (as determined from WATER-

9 emission estimates for key process areas) operating simultaneously Scenario 2: All on-site sources at the WWTP (as determined from WATER-9 emission estimates for key process

areas), as well as off-site sources within the study area (consisting of sewage pumping stations and horse stables), operating simultaneously

Scenario 3: All sources (on-site and off-site) operating simultaneously, assuming that the biosolids storage lagoons are removed

Scenario 4: Repeat modelling of the Scenario 1 conditions but with the substitution of measured emission rates from odour sampling at key process areas

The model results indicate that the areas most affected coincided with the location of the majority of the complaints, which came from along Mill Park Drive and Morningview Place. The theoretical and field sample odour values used as inputs to the models are reproduced in Table 23. The highest source of odour, based on odour units (OU), was determined to be the biosolids lagoons, which were shown to account for 79% of the WWTP total. Offsite odour sources were not found to be of any significance.



Table 22 Odourous Emissions (XCG, 2007) Source Emission Rate Used For Modelling

(OU/s)1 Percentage of Odour Emissions

(%) Source of Emission Estimate

Inlet Works

Bar Screens 3.84E+02 1% Sampling Data

Grit Separators 4.40E-02 1% WATER-9

Primary Clarifiers 1.94E+03 4% Sampling Data

South Plant

Aeration Tanks 4.45E+03 9% Sampling Data

Secondary Clarifiers 1.11E+01 <1% WATER-9

North Plant

Aeration Tanks 2.32E+03 5% Sampling Data

Secondary Clarifiers 5.71E+00 <1% WATER-9

Return Sludge Building 2.42E-01 <1% WATER-9

Outlet Works

Flare number 1 and 2 2.73E-01 <1% Estimated

Biosolids Lagoon 1 2.46E+04 52% Sampling Data

Biosolids Lagoon 2 1.28E+04 27% Sampling Data Note: 1. Values based on hydrogen sulphide modeling in Water9 Under Scenario 1 (only on-site sources with WATER-9 based emission rates), the maximum odour impact at locations of complaint nearest the WWTP was 13 OU/m3. Under this scenario, the maximum impact just south of the WWTP was 26 OU/m3. Under Scenario 4 (Scenario 1 using odour sampling emission rates), the maximum odour impact at locations of complaint nearest the WWTP was 12 OU/m3. Under this scenario, the maximum impact just south of the WWTP was 21 OU/m3. Under Scenario 3 (Scenario 1 with both lagoons removed), the maximum impact was reduced to 1.3 OU/m3. The lagoons are thus seen to be the source contributing most to odour concerns at surrounding receptors. The XCG study (2007) along with the Region of Waterloo Wastewater Treatment Master Plan (2007) calls for decommissioning of the lagoons. Although the report acknowledges that odour mitigation will be required in the interim, exact control methods were left for future study. The report notes that the odour from the existing Headworks Building generally do not migrate any appreciable distance outside of the building, but the odours are noticeable inside. Odour control is recommended as part of the Phase 3 plant upgrades. The report recommends all future modelling be completed using local climate data (from a then new site based metrological station correlated to Waterloo Wellington Airport) to ensure that local geographic effects are captured

5.1.1.2 CH2M HILL Study (2008)

In 2008, CH2M HILL Canada Limited (CH2M HILL) was retained by the Region to review the XCG study and other existing information, develop mitigation measures, prepare a conceptual design of odour mitigation alternatives, and recommend a preferred approach to mitigate offsite odour impacts. The report reviewed process control parameters and methods, noting that the effectiveness of chlorine (NaClO) for odour control is not equal for all compounds. Where reduced sulphur compounds are not the dominant problem, chlorine may not be effective at suppressing odour. A simplified analysis illustrated that the chlorine levels used were



not likely to be sufficient to form a suitable watercap over the biosolids lagoons. The report also discusses process changes that occurred since the XCG study (XCG, 2007), including: Biosolids diversion (thus eliminating the storage of offsite biosolids) Ferrous sulphate addition at the primary clarifier inlets Revised transport practices that reduce or eliminate the need to transfer sludge from April to October

While reviewing modelling activities of the XCG Study (XCG, 2007), CH2M HILL recommended the use of Bay Area Sewage Total Emissions (BASTE) model rather than WATER-9 to develop theoretical emissions data. CH2M HILL indicated that the XCG methodology, in addition to the unique circumstances in the summer of 2007, may have resulted in the over-estimation of reported emission rates for some sources. CH2M HILL conducted additional testing of the lagoons during 2008, including a complete analysis of the odour causing contaminants present in the liquid phase as well as odour compounds in the lagoon sludge off-gas; odour sampling was found to be in the same range as the previous study. The analysis of the lagoon emissions indicated that common sulphurous odour compounds were unlikely to be responsible for the odour issues. CH2M HILL also investigated digester gas composition and concluded that it is typical and would not be considered a significant odour source. Finally, a petroleum-like or chemical odour from was noted in the sludge. The source of this atypical odour was unknown. CH2M HILL (2008) recommended that odour sampling be conducted at the influent energy dissipation chamber to assess the odourous emissions. In addition, they recommended that where process improvements have been made, retesting of odourous emissions should take place. Finally, CH2MHILL (2008) recommends that testing for amine compounds be conducted. CH2M HILL reviewed short term mitigation options, including process controls, liquid controls, gas-phase controls and aerosol treatment of ambient air. A series of process control improvements are recommended. In the short term, bench tests illustrated that hydrogen peroxide is indicated as the preferred treatment method; the 2008 report indicates various ways this can be used for the lagoons. Finally if the short term methods do not reduce complaints related to odour, a more comprehensive, plant wide mitigation strategy would be required. If additional interim odour mitigation is required, CH2M HILL recommends that odour mitigation measures target the headworks, primary clarifiers and the influent channel.

5.1.2 Preliminary Design Odour Assessment

The source emissions from the XCG study (XCG, 2007) report were used to complete a Preliminary Design odour assessment. Both historical reports are in agreement that the biosolids lagoons are by far the main contribution of odourous emissions. Based on the previous modelling, the decommissioning of the biosolids lagoon will reduce the odour emissions by approximately 79%. The removal of the Plant 1 aeration tanks will remove an additional 5% of odour emissions. Plant 1 secondary clarifiers are also planned to be removed; however, these tanks only contribute <1% of odour emissions. Plant 2 aeration tanks will remain in service; however process upgrades to the aeration system (mechanical aerators to fine bubble diffusers) are expected to reduce odourous emissions. The addition of aeration tanks and secondary clarifiers for Plant 3 and 4 will add odour emissions but with a lower magnitude as sources removed as part of Plant 1 decommissioning due to the use of fine bubble aeration system. Following the Phase 3 Upgrades overall plant wide odour emissions will be greatly reduced compared to existing and historical conditions. A qualitative assessment of odourous emissions is shown in Table 23.



Table 23 Qualitative Assessment of Odourous Emissions, Plant Wide Facility/Equipment Action Odour Emission Result

Existing headworks facility (screens) Removed -1%

Existing grit separators (detritors) Removed -1%

New headworks facility New, with odour control +0.1% (90% odour removal)

New vortex-type grit removal systems New, with covers +0.5% (conservative estimate)

Existing primary clarifiers Upgrades No change (ex. 4%)

Existing aeration tanks – Plant 1 (north plant) Removed -5%

Existing aeration tanks – Plant 2 (north plant) Upgrades, fine bubble diffusers -3%

New aeration tanks – Plant 3 and 4 New, 4 tanks uncovered +5-10%

Existing secondary clarifiers – Plant 1 Removed -<1%

Existing secondary clarifiers – Plant 2 Upgrades No change (ex. <1%)

New secondary clarifiers – Plant 3 New, 8 units uncovered +<2%

Return sludge building Removed -<1%

New Thickening Building New, with odour control +0.1% (90% odour removal)

Existing flares

Existing biosolids – Lagoon 1 Removed -52%

Existing biosolids – Lagoon 2 Removed -27%

NET CHANGE -75% Note: 1. Percentages are relative and based on the total values in the data provided by the 2007 report by XCG.” Final Draft Report- Odour Investigation

Study at the Kitchener WWTP, Kitchener Ontario” Based on the high level analysis, overall odour emissions are expected to decrease by approximately 75% once all plant upgrades have been completed. With the lagoons removed, the largest contributors of odour will become the aeration tanks followed by the primary clarifiers. The use of fine bubble aeration systems will reduce the impact of the aeration tanks. Although the previous modelling work did not include a scenario that represented the final plant construction, the scenario that was modelled removed the lagoons which constituted 79% of the odourous emissions. Prior to lagoon removal, the off-site maximum level was 26 OU/m3 and 13 OU/m3 at a receptor and corresponds well to the complaint data. With the biosolids lagoons removed (with all existing facilities remaining) produced maximum levels of 1.3 OU/m3 (off-site) and 0.23 OU/m3 (sensitive receptor) with respect to hydrogen sulphide (H2S). Ammonia odour impacts were modelled at 1 OU/m3 (off-site) and 0.25 OU/m3 (sensitive receptor). It is reasonable to assume that the expected maximum levels will not greatly increase due to the ~5% increase from the plant expansion as predicted in Table 22. However, the geographic locations of the sources have changed, which may impact the level and location of off-site concentrations. This assessment was conducted using a qualitative analysis for the Preliminary Design work. Additional source testing and/or modelling is recommended to better assess plant wide odour emissions and off-site impacts at receptors for the ultimate upgrade scenario during detailed design. It must be noted that during the actual lagoon decommissioning work there could be temporary increases in odour emissions.

5.1.3 Quality of Information and Next Steps

The previous studies (XCG, 2007 and CH2M HILL, 2008) provide sufficient information to develop a Preliminary Design odour management plan. Air dispersion modelling for odour (H2S and ammonia) was completed in the 2007 Study. The scenarios modelled included a base case with the current Plant 1, Plant 2 and lagoons in operation and compared it with a scenario which removed the lagoons. Although the lagoons constitute a majority of the odourous emissions, the scenarios used in the XCG Study (2007) do not take into account the final WWTP layout, which



includes the addition of new facilities as part of Plants 3 and 4. The previous reports were also focused on odour impacts and did not cover in detail, any other air quality contaminants that may be emitted from the WWTP. Additional air dispersion modelling is required to assess the full air quality impact (including odour and other contaminants) of the final upgrades to the Kitchener WWTP (ultimate scenario). This modelling should be done in-conjunction with a site-wide Environmental Compliance Approval (ECA) application. The ECA application is typically initiated during detailed design so that the equipment and air pollution equipment selected is accurate and up to date. In lieu of modelling and assessing the largest contributions to air quality and odour emissions for the ultimate scenario, the Preliminary Design will proceed based on the odour management plan outlined in this section. During detailed design and when additional modelling is required the following data gaps should be considered: Determine and/or agree with regulators the plant wide emission standards or objectives Include other air quality contaminants in modelling Testing for amines, and sources of odour that had not previously been investigated (Stantec, 2008) Additional odour testing to be conducted as upgrades are made to the facilities, and process changes are made

operational to ensure that data used for design is reliable Assess complete odour spectrum, including other odourous compounds. The XCG Study (2007) included

hydrogen sulphide and ammonia as representative substances for odour modelling Re-assess odour sampling and estimation and generate new base modelling, the CH2M HILL Study (2008)

reviewed the methodology used to generate odour emissions and noted several recommendations to improve accuracy

A formal comparison of the plant metrological station data and that of Waterloo Regional Airport should be conducted.

Investigate correlations (if any) between odour complaints and local metrological conditions.

5.2 Process Design

The Preliminary Design odour management plan and strategy will be a combination of removing high odour emitting sources (e.g., biosolids lagoons), utilizing process enhancements to reduce the formation/release of odourous compounds (e.g., use of fine bubble diffusers), containment (e.g., covered channels and tanks) and capture of any odours within building envelope for treatment (e.g., biofilters for the Headworks and Thickening Buildings). Details on the process area specific design of odour management are provided in Section 8 for Lagoon Decommissioning (Contract 1a), Section 11.4 for Headworks (Contract 3a), and Section 16.2.7 for Administration Building (Contract 5a).



6. Evaluation of Upgrade Alternatives Detailed evaluations of upgrade alternatives were performed as part of the Site Wide Facility Plan (AECOM, 2011). The evaluation and decision making processes leading to the selection of a preferred approach were documented in the Site Wide Facility Plan TMs. The majority of the preferred approaches identified in the Site Wide Facility Plan were carried forward in the Preliminary Design; however, the following key deviations from the Site Wide Facility Plan were made: Primary effluent flow distribution Digester heating Digester operation Digester configuration Plant 2 RAS/WAS pumping station design and location

6.1 Primary Effluent Flow Distribution

The existing primary effluent conduit incorporates stop-gate grooves at strategic locations to passively control flow distribution between Plant 1 and 2. These stop-gate grooves are reliable but are not flexible enough to achieve a reliable flow split under a range of flow conditions. In addition, they cannot be automatically controlled, which should be an important feature of the upgraded plant. New actuated gate structures and flow measurement will be included to facilitate flow splitting between Plants 2, 3 and 4. Flow distribution downstream of the primary clarifiers will require modifications to ensure the full range of anticipated flows can be readily diverted to Plants 2, 3 and 4 without introducing significant system headloss. Under normal conditions, the flow will be distributed approximately evenly between the three (3) plants; therefore, each plant will treat approximately one-third of total plant flow. Two (2) options were considered for primary effluent flow distribution: Option 1, the original concept presented in the AECOM proposal for the Phase 3 Upgrades, and Option 2, the design concept developed and presented to the Region during the Preliminary Design.

6.1.1 Primary Effluent Distribution Option 1: Proposal Concept

The existing Plant 1 flow control chamber will not likely have adequate capacity to convey flow to the upgraded plant, due to the significantly higher peak factor in the existing plant compared to the original design peak capacity and the long distance to Plant 3 and 4. The primary effluent distribution chamber option presented in the proposal called for a larger chamber at the primary clarifiers, a primary effluent feed pipe to Plant 3 and 4, and a second flow split chamber installed at the take off point to the Plant 3 aeration tank influent channel. The existing primary effluent conduit already incorporates stop-gate grooves at strategic locations to passively control flow distribution between Plant 1 and 2. The proposal concept utilizes this configuration by using an actuated slide gate located at the mid-point of one (1) primary clarifier to direct two thirds of flow to Plant 3 and 4 without increasing headloss. In addition, downward opening weir gates will be assessed for minor flow control adjustments between each plant. These gates offer improved flow control and floatables passage compared to traditional sluice gates. Figure 4 presents a preliminary sketch of flow distribution modifications required to the existing primary effluent conduit for Primary Effluent Distribution Option 1.



Figure 4 Primary Effluent Distribution Option 1: Existing Primary Effluent Chamber Modifications

An overview schematic of the primary effluent distribution option 1 is presented in Figure 5

Figure 5 Primary Effluent Distribution Option 1 Schematic

Option 1 carries a high level of operational complexity due to the system’s dependence on the number of primary clarifiers in operation. Construction requirements would also be high due to the need to maintain operation during the construction period. Due to the significant operational and construction complexity, and the need to operate two flow distribution chambers, a primary effluent distribution Option 2 was developed during the Preliminary Design period.

and 4



6.1.2 Primary Effluent Flow Distribution Option 2: Preliminary Design Concept

Primary Effluent Flow Distribution Option 2 uses a single flow distribution chamber constructed adjacent to the primary clarifier effluent channel. The primary effluent would enter the chamber and be split using three (3) automatic weir gates; the height of the weir gates would be adjusted to allow for equal splitting of flow between the three (3) plants. A concrete baffle wall would be used to provide energy dissipation in the chamber. A schematic of this option is presented in Figure 6.

Figure 6 Primary Effluent Distribution Option 2 Schematic

6.1.3 Comparison of Primary Effluent Distribution Options

A comparison of Primary Effluent Distribution Options is presented in Table 24. Table 24 Comparison of Primary Effluent Distribution Options

Option 1 Option 2

Flow Split Requirements 2 flow control chambers 1 flow split chamber 5 weir gates

1 flow split chamber 3 weir gates

Flow Control Operation 5 weir gates at 4 locations Low flexibility

3 weir gates at 1 locations High flexibility

Construction Connection to existing Plant 2 influent pipe 1200 mm pipe to Plant 3 (~ 300 m) 1050 mm pipes within Plant 3 (~ 75 m)

Connection to existing Plant 2 influent pipe 2 x 1050 mm pipe to Plant 3 - (~ 300 m) (same trench) 1050 mm pipes within Plant 3 (~ 75 m)

Risks

Requires shut down of 1 clarifier - twice More conflicts with existing underground utilities (duct

banks, compared to only centrate/plant effluent line in new design)

Requires shut down of 1 primary clarifier for chamber construction

Plant 3 influent pipes need to cross Plant 2 influent pipe from underneath

Construction Cost Similar ($1.3M, including pipe installation)

6.1.4 Option Carried Forward

Based on the improved operational flexibility, constructability and lower risks, Primary Effluent Distribution Option 2 has been carried forward in the Preliminary Design. Additional details on Primary Effluent Distribution Option 2 are presented in Section 13.2.1.



6.2 Digester Heating

The Site Wide Facility Plan recommended the reuse of the three (3) existing boilers for digester heating. The potential for reuse of the existing boilers was examined further during the Preliminary Design phase and an evaluation of their condition and the upgrades required to bring the existing boilers up to current codes and standards and to achieve a reasonable design life was conducted. The evaluation was performed to assess the reliability, redundancy, and cost-effectiveness of the option of rehabilitating and retaining the existing boilers compared to the option of installing new boilers. The future combined heat and power system (CHP) was considered in this analysis. The detailed analysis of digester heating options is presented in PDM 7 Digester Heating and Operation, presented in Appendix C. This section provides an overview of the findings presented in PDM 7.

6.2.1 Digester Heating Option 1: Rehabilitate Existing Boilers

The Kitchener WWTP currently has three (3) boilers in use for digester heating as well as some building heating. The existing digester heating system requires significant repairs and upgrades to comply with current TSSA requirements and to provide a reasonable service life.

6.2.1.1 Existing Boiler Description

The three (3) dual fuel (i.e., natural gas and digester gas) type hot water boilers and three (3) digester gas boosters were installed in 1998 to provide digester and building space heating. Table 25 presents the technical data of the existing boilers and digester gas boosters. Table 25 Existing Boilers and Digester Gas Boosters

Item Boiler Digester Gas Booster

Manufacturer Boiler Smith Spencer Turbine

Number 3 3

Model/Serial Number CF2LW-125-GG-30/51098603 GH-2005-HMOD/805642

Rated Capacity 125 BHP

Maximum Heat Output 4,255 MJ/h

Supply/Return Water Temperature 82/71°C

180/160oF

Motor 3.7 kW 5 hp

Rated Capacity/Digester Gas Requirements 150 BHP

1,470 kW 5,292 MJ/h

7.08 m3/min at 75oF and 14.14 psia

Differential Pressure 47 WG

6.2.1.2 Rehabilitation Requirements

An assessment by the TSSA, conducted on April 22, 2010, determined that the existing gas booster installation does not comply with the current Code for Digester Gas and Landfill Gas facilities. In particular, the installation lacks an emergency shutdown switch external to the room; both gas boosters and boilers bear no certification label, and are not approved equipment. The gas train control systems do not meet the current code requirements. Relocation of the existing boilers to the Energy Center would trigger a TSSA safety approval process and require significant improvements. Major improvements are required for TSSA compliance and to achieve reliable service for



the remaining life of the system, which would require the boilers to be sent to the manufacturer’s workshop for repairs and rehabilitation. These improvements would ensure the existing boilers to have another 10 to 12 years of service life. The boilers would have to be replaced at that time to provide the design life expected for the Phase 3 Upgrades

6.2.1.3 Construction Sequencing

During the Preliminary Design, it was determined that the existing building housing the existing boilers must be demolished to make way for the new Energy Centre and Thickening Building. Therefore, if reused, the existing boilers would need to be relocated to a temporary structure prior to permanent installation in the new Energy Centre. Costs would be incurred for relocation, reconnection, and re-commissioning twice. There would also be risks of damage to the units when being relocated multiple times. Furthermore, reliability and redundancy would be somewhat reduced while the units are being relocated and rehabilitated. The relocation process itself would negatively impact the duration of the construction contract.

6.2.2 Digester Heating Option 2: New Boilers

Concerns regarding the cost and risk of multiple relocations, combined with the shorter life of rehabilitated existing boilers resulted in the decision to assess the possibility of incorporating new boilers in the design. Benefits to providing new boilers include: Reliable service of between 20 and 30 years without major upgrades Multiple relocations of the existing boilers is eliminated and the actual number of boilers requiring temporary

relocation can be based on the actual heating requirement during construction Installation of new boilers and digestion upgrades would be in parallel New boilers would be sized to meet the updated digester heating requirements and planned space heating

requirement, allowing for more flexibility in terms of boiler sizing and foot print At the time of the review, three new boiler options were considered: 1) Two (2) new larger boilers (1 duty, 1 standby), which can meet average heat demand with typical turndown; this

option requires the relocation of the existing boilers to a temporary enclosure and that they operate until the new boilers are commissioned in the Energy Centre.

2) Three (3) new smaller boilers (2 duty, 1 standby), which can meet most heat demands with one (1) unit operating and the maximum heat demand with two (2) units operating; this system offers greater operating redundancy and reliability.

3) Two (2) new boilers sized based on recovered heat from a future CHP system; this system requires the acceptance of the lack of redundancy and reliability of smaller boilers.

A subsequent decision to install the boilers in the new digester complex, rather than the Energy Centre, rendered the first option irrelevant. After the CHP is operational, the new boilers would normally be on standby, but would produce hot water when the CHP is offline for maintenance/repair or the digester heating demand exceeds the heat capacity of the CHP. Therefore, a full redundant boiler heating system has been considered. The standard turn down ratio of the boilers when burning digester gas is 4:1, therefore, either two (2) boilers (250 BHP each, 1 duty and 1 standby) or three (3) boilers (150 BHP each, 2 duty and 1 standby) can meet the lowest average digester heating requirement. However, boilers are required to produce supplement heat during cold days when waste heat from the CHP is not enough to heat the primary digesters and building space. Therefore, three (3)



smaller new boilers would provide greater flexibility than two larger boilers and is the new boiler option that was considered in the evaluation.

6.2.3 Comparison of Digester Heater Options

A comparison using life cycle costing is presented in Table 26. Table 26 Boiler Comparison Life-Cycle Costing (Based on 5% interest, 2% inflation)


Due to the issues related to multiple relocations, significant code retrofits and uncertainty as to the remaining life of the existing boilers, it is recommended that new boilers be provided. In order to provide adequate redundancy and reliability and due to the uncertainty of the timing of installation and commissioning of the CHP system, it is recommended that three (3) boilers (2 duty, 1 standby), be provided. This system can meet most heat demands with one (1) unit operating and the maximum heat demand with two (2) units operating.

6.3 Digester Operation

6.3.1 Background

It was assumed through the Site Wide Facility Plan phase that the existing digester parallel feed mode of operation would be maintained for the Phase 3 upgrades. The intent was for each digester to be fed equally and sequentially to balance the loading and provide the appropriate detention time as required for adequate sludge stabilization and by Ontario standards. However, based on subsequent discussions with the Region during the Preliminary Design phase, the possibility of providing flexibility for series operation of the digestion system was explored. A detailed discussion on this matter is presented in PDM 7 Digester Heating and Operation (Appendix C).

Cost Option 1 Option 2

Relocate Existing Boilers Purchase New Boilers 2016 2026 2016 2026

Upgrade Existing Boilers Minimum improvement to meet TSSA codes $30,000 $0 $0 $0

Cleaning and re-paint $30,000 $0 $0 $0

Re-tubing $30,000 $0 $0 $0

Burner control panel replacement $45,000 $0 $0 $0

Pressure valves replacement $85,000 $0 $0 $0

Gas booster improvement $15,000 $0 $0 $0

Purchase new boilers $0 $808,795 $808,795 $0

Purchase new gas boosters $0 $90,000 $90,000 $0

Salvage valve of existing equipment $0 $0 $15,000 $0

Installation $100,000 $269,639 $269,639 $0

Start-up and certification $20,000 $20,000 $20,000 $0

Subtotal $355,000 $1,188,434 $1,203,434 $0 Total NPV of Capital Costs $1,244,372 $1,203,434

Total NPV of Fixed O&M Costs $91,891 $1,380,083

Total NPV 1,336,264 1,380,083




Operation of the existing Kitchener primary anaerobic digesters in series may provide improved performance over operation in parallel. Designing the system to operate in both parallel and series modes of operation would result in minimal additional costs but would add to the overall system complexity. In order to provide operating flexibility, the preliminary design is based on flexibility for both parallel and series operation.

6.4 Digestion Configuration

A digester mixing system using chopper pumps located in the existing Primary and Secondary Digester Control Buildings was the original design basis selected for both primary and secondary digester mixing. However, during Preliminary Design development, a number of configuration deficiencies were identified that preclude the feasibility of this digester mixing system. Detailed discussions on this matter and a number of options were presented to the Region and OCWA at a special project meeting on January 11, 2012. This section provides an overview of the discussion presented at the Meeting.

6.4.1 Digester Configuration Limitations and Deficiencies

A number of limitations affecting digester system configuration were identified during the Preliminary Design: 1. Mixing Pump Size 2. Gas Train Buried 3. Transfer Pumps on Mezzanine Level 4. Long Distance between Heat Exchangers and Boilers 5. Compatibility with Future CHP System The primary issue identified was the limited basement space available in both the existing Primary and Secondary Digester Control Buildings to house the mixing and pumping equipment. The current basement footprint is too small to contain the mixing system, and would cause significant operation and maintenance (O&M) issues. Alternatives to solve the configuration deficiencies were investigated: 1. Eliminate common standby primary digester mixing pump 2. Construct a large building extension to consolidate the digester mixing and heating systems, the boiler hot water

system, the air system of the membrane gas holder, and the digested sludge pumping 3. Use an alternative primary digester mixer technology: draft tubes, bubble guns, confined gas mixing, or linear

motion mixers

6.4.2 Digester Configuration Option 1: No Standby Primary Digester Mixing Pump

A simple approach to mitigate the space limitation in the basement of the Primary Digester Control Building would be to eliminate the common standby mixing pump. Each primary digester would normally have a dedicated mixing pump, and the piping layout would allow a mixing pump to alternatively service both primary digesters when one mixing pump is offline. This option is considered feasible because the ability to mix intermittently already exists. This approach would provide more area for piping layout but would not mitigate the issue of the height limitation underneath the major mixing piping, nor would it address the ventilation problem; therefore, this option would not address the O&M issues. This option could also create a digestion stability issue because anaerobic bacteria are sensitive to sludge mixing and both primary digesters would lose continuous mixing while a mixing pump is taken out for major maintenance.



6.4.3 Digester Configuration Option 2: Large Building Extension with Basement

The construction of a larger building extension with basement between the two primary digesters and the secondary digester (No.3) was investigated. With this approach, the current secondary digester No. 3 with the floating cover, which is in better condition than the currently used digester No. 4, would be retained. The building extension would house the mixing systems for both primary digesters, secondary digesters, the digester heating system (including heat exchangers and recirculation pumps), and the gas handling equipment and gas header. The sludge transfer pumps would be housed in the basement of the existing Primary Digester Control Building. This configuration greatly reduces pump suction length and would increase available net positive suction head (NPSH), allowing the use of the sludge transfer pumps for emptying the digesters. The boiler hot water system would be located in this building extension, enabling the hot water system and the heat exchangers to be closer to each other, minimizing heat losses along the pipelines and complexity of having the equipment in two separate buildings. This option would create adequate space in the basement to house the digested sludge pumping system. Relocating the digested sludge pumping system from the basement of the existing Administration Building into the new building extension, in the future, would significantly reduce the pump suction headlosses and increase available NPSH. A centralized MCC and electrical control room in the building extension for the power supply and operation control of the whole digestion system would improve digestion operation convenience. The ground floor would contain rooms for the heat exchanger, MCC, boiler, gas, and air system to the gas header cover. The basement would contain the primary digester mixing pump, main gas header, and secondary digester mixing pump rooms. The sludge recirculation pumps would be located in the primary digester mixing pump room, and the digested sludge transfer system would be in the secondary digester mixing pump room.

6.4.4 Digester Configuration Option 3: Alternative Mixing System

Several alternative mixing options with lower space requirements were considered; the mixing option used as the basis for Option 3 was draft tube mechanical mixers. This type of mixing system is used at the Region’s Galt WWTP in Cambridge. Draft tube mechanical mixers use a mechanical propeller housed within a draft tube to induce either a top to bottom, or bottom to top mixing effect within the digester. The draft tubes can be designed to be roof-mounted and inserted directly into the tank, or built outside on the periphery of the tank. A special propeller design is used to minimize fouling, motor overload, and other mechanical problems. Both types are suitable for upgrades to the existing digesters and allow service during normal digester operation without the need to de-gas or de-water the digesters.

6.4.5 Comparison of Digester Configuration Options

The three digester configuration options identified during the Preliminary Design are compared in Table 27.



Table 27 Digester Configuration Option Comparison

Option 1: Larger Primary and Secondary

Digester Control Building Extension

Option 2: New Separate Control Building for Primary and Secondary Digesters

Option 3: Mechanical Draft Tube Mixers

Significant Advantages

Improved reliability and process stability

Equipment accessibility; Gas piping conditions improved Eliminate existing secondary

chamber (code issues) Retain preferred secondary digester

– frees up more space Sludge transfer pumps at lower level

– more effective range All digestion process equipment in 1

or 2 locations Can accommodate sludge transfer

pumps (improve operating range)

Improved reliability and process stability

Equipment accessibility; Gas piping conditions improved Eliminate existing secondary

chamber (code issues) Retain preferred secondary digester

– frees up more space Sludge transfer pumps at lower level

– more effective range All digestion process equipment in 1

or 2 locations Can accommodate sludge transfer

pumps (improve operating range) Constructability better than Option 1

Cost Constructability – digester

modifications but limited building expansion

Proven performance Allows sludge transfer pumps to be

installed in basement – better operating range

Simplified piping

Significant Disadvantages

High Cost Constructability – significant

interfaces with existing digesters

Cost

Less accessibility for O&M Require crane for maintenance Moving equipment inside digester Digestion processes still spread out

Increase in Cost Compared to Original Option

$1,625,000 $2,225,000 $50,000

Digester Configuration Option 1 does not mitigate the confined space and problematic ventilation issues and is therefore not recommended. Digester Configuration Option 2 mitigates the confined space issue in both the existing Primary and Secondary Digester Buildings, and consolidates digestion system control including the digested sludge pumping. However, Option 2 requires significant greater building investment and existing yard piping re-routing. Digester Configuration Option 3 mitigates the basement space limitation in the existing Primary Digester Control Building and reduces annual energy usage. However, this option carries O&M difficulties, and does not mitigate the confined space issue in the secondary digester control building.


Based on the presentation and the Region feedback received and the advantages offered (presented in Section 6.4.5), Digester Configuration Option 2 was recommended and has been carried forward in the Preliminary Design phase.

6.5 Plant 2 RAS/WAS Pumping Station

The issues related to the design and original location of the Plant 2 RAS/WAS pumping station were presented to the Region during Pre-Design Meeting No. 7 (held on January 11, 2012) and Pre-Design Meeting No. 8 (held on February 6, 2012). This section provides an overview of the discussion presented at the Meetings.

6.5.1 Plant 2 RAS/WAS Pumping Station Original Concept

The Plant 2 RAS/WAS pumping station design concept presented in the Site Wide Facility Plan (AECOM, 2010) was based on the design used for the Plant 3 and 4 RAS/WAS pumping stations (i.e., 1 duty RAS pump assigned to each secondary clarifier and 1 common standby shared by each pair of clarifiers) and constructed to the north of the existing Plant 2 RAS/WAS screw pumping station. However, space constraints caused by the placement of existing infrastructure, depicted in Figure 7, would likely cause constructability issues with this configuration. The site



available to construct the Plant 2 RAS/WAS pumping station is constrained on the west by the presence of the adjacent Secondary Clarifier No. 2, on the south by the existing pumping station, and to the east by the existing asphalt road. Furthermore, the routing of the secondary clarifier RAS piping would be problematic due to unknown soil and buried pipe conditions.

Figure 7 Existing Plant 2 Secondary Clarifier and Return Sludge Screw Pump Layout

To mitigate these issues, a revised concept was developed to construct the Plant 2 new RAS/WAS pumping station in two (2) stages, such that approximately half of the pumping station would be constructed on the site of the existing screw pumping station. However, the placement of the Plant 2 RAS/WAS pumping station either entirely or partially on the available land to the north of the existing screw pumping station would require tie-ins to the existing RAS piping to occur in between the secondary clarifiers and the existing screw pumping station. If a RAS pipeline was to be damaged during construction, the replacement of some or all of the RAS pipelines may be required, which would have a significant impact on construction schedule and cost. The condition of the piping is not known, and there is also some concern that fill concrete may have been used to anchor the pipelines along certain lengths, which would also complicate construction. Therefore, it is highly undesirable to intercept the existing RAS piping between the existing secondary clarifiers and the screw pumping station. The original construction concept and the proposed two stage construction alternative were deemed to be unworkable in a constructability review; two options were developed to mitigate these issues.

6.5.2 Plant 2 RAS/WAS Pumping Station Option 1

Plant 2 RAS/WAS Pumping Station Option 1, presented in Figure 8, is a modification of the original design basis and uses an identical pumping station design to that of Plants 3 and 4 (i.e., 4 duty, 2 standby RAS pumps and 1 duty, 1 standby WAS pumps). However, Option 1 places the pumping station in the footprint of the existing Plant 2 RAS/WAS screw pumping station.

Original location proposed for Plant 2 RAS/WAS

Pumping Station



Figure 8 Plan View Schematic of Plant 2 Pumping Station Alternative Layout Option 1 (not to scale)

During construction, temporary submersible pumps (other temporary pumping systems would also be considered) would be placed into the existing wet well at the foot of the screw pumps and used to pump RAS/WAS via temporary force mains. Meanwhile, the existing screw pumps would be decommissioned, demolished, and the new Plant 2 RAS/WAS pumping station constructed in its place. In the second phase of construction, the new Plant 2 RAS/WAS pumping station would be constructed on the former site of the screw pumping station. Plant 2 would be taken offline to tie in the new pumping station to the existing activated sludge lines from the secondary clarifiers in the old pumping station wet well. This construction concept reduces the length of time Plant 2 would need to be offline and reduces risks related to RAS piping tie-ins by completing the tie-in to the existing activated sludge piping in the existing screw pumping station wet well, which would minimize disturbance to the existing activated sludge pipes, the condition of which is unknown. This concept would allow Plant 2 to maintain full operation for most of the construction period, although a 1 to 2 month shut down would be required to complete activated sludge lines and other piping tie-ins.

6.5.3 Plant 2 RAS/WAS Pumping Station Option 2

Plant 2 RAS/WAS Pumping Station Option 2, presented in Figure 9, uses a modified pumping station layout. Option 2 reuses the existing activated sludge piping from each clarifier and the existing wet well/chamber at the foot of the screw pumps. The activated sludge from the wet well would be directed to a new RAS/WAS pumping station through a common discharge line. The activated sludge discharged from each secondary clarifier would be controlled using either adjustable weirs or telescoping bell mouths on each activated sludge line from the secondary clarifiers. The sludge from the common wet well/chamber would be discharged to the pumping station using a single RAS suction pipeline.



Figure 9 Plan View Schematic of Plant 2 Pumping Station Alternative Layout Option 2 (not to scale)

This pumping system concept consists of weir controlled (hydrostatic) sludge removal followed by a variable speed RAS/WAS pumping station. The weirs would create a hydraulic break, allowing each clarifier to be controlled independently. The weirs would be located in the wet well of the existing Plant 2 screw pump pumping station. This existing Plant 2 wet well would be linked to a new RAS/WAS pumping station wet well via a new activated sludge pipeline. The combined flow would be measured and the rate used to control weir adjustment via SCADA. The speed of the RAS pumps would be adjusted to maintain a constant level in the new wet well. The pumping station would house 3 RAS pumps (2 duty, 1 standby) and 2 WAS pumps (1 duty, 1 standby) and occupy a smaller footprint than the current design. The smaller footprint would translate into potential capital cost savings and schedule savings because it can be built completely off line. Although this option would allow for independent control of the secondary clarifiers (that are hydraulically independent) through adjustment of the weirs/telescoping bell mouths, it does not use the same design concept as the Plant 3 and 4 RAS/WAS pumping stations, which have one (1) RAS pump assigned to each secondary clarifier.


Based on Region preference toward using a common RAS/WAS pumping station design, Plant 2 RAS/WAS Pumping Station Option 1 was selected to be carried forward in Preliminary Design.



7. Lagoon Decommissioning (Contract 1a) The Region has a history of odour complaints related to the biosolids lagoons. An odour mitigation program was implemented to minimize odours by adding a water cap (minimum depth of 0.45 m) to the lagoons by pumping post-chlorinated plant effluent and sodium hypochlorite to cover the biosolids when they are being pumped in or out of the lagoons. The Region also mists an odour masking agent around the perimeter of the lagoon on an as required basis. The Region implemented on-site temporary dewatering of biosolids to eliminate the addition of “new” biosolids to the lagoons during construction of the upgrades at the WWRMC. The Region made a long term commitment to decommission the lagoons by the end of 2015. The WWRMC was constructed in Phase 1 of the Kitchener WWTP upgrades and was recently commissioned. All biosolids are now pumped directly to the WWRMC, eliminating the need for biosolids storage in the lagoons. The Phase 3 upgrades include the decommissioning of the sludge lagoons, thereby permanently eliminating the single largest source of odours. The decommissioning of the lagoons will free up sufficient land for the construction of the new Plant 3 and 4 secondary treatment. A full report on the lagoon characterization studies and decommissioning plan is presented in Appendix I. A summary of the key elements is presented in this section. Lagoon 1 decommissioning will include the removal and/or management of the following materials: Biosolids (approximately 1.5 m thick) Clay liner (approximately 1 m thick) Non-woven geotextile (6 oz.) liner Select areas of contaminated berm materials (including liner and stones) Yard piping Odour control equipment and piping currently surrounding the lagoon

Lagoon 2 will be decommissioned using a similar approach to Lagoon 1. A temporary or permanent storm water management pond may be constructed within a portion of Lagoon 2 upon completion of the lagoon decommissioning and the remaining berms will assist with future flood control requirements. The decommissioning of Lagoon 2 will include the removal of the following materials: Supernatant Biosolids (approximately 2.3 m thick) Yard piping Odour control equipment and piping currently surrounding the lagoon

Lagoon decommissioning activities will also involve demolition of the lagoon booster pumping station located south of Lagoon 1 (adjacent to the existing Site entrance/exit). Lagoon decommissioning drawings (Series 200) are contained in Appendix A.

7.1 Key Considerations

Considerations for assessing decommissioning approaches and identifying the preferred alternatives were as follows: Minimize the impact of truck traffic on the nearby residential neighbourhood when possible Minimize odour emissions during lagoon decommissioning activities



The preferred method of addressing soil (berm material) impacts is for any contaminated soil above applicable MOE SCS to be excavated for off-site landfill disposal

The preferred method of addressing the clay liner and groundwater impacts is to complete a screening level ecological risk assessment to ensure there is no potential risk to the Grand River

Biosolids handling and lagoon decommissioning approaches will comply with the applicable federal, provincial, and local regulations, as appropriate

One of the Region’s primary concerns is odour control during decommissioning activities. To meet this objective, approaches that follow current proven practices and the final approach to odour control during the lagoon decommissioning will include one or more of the following mitigation measures: Preference to pumping/dredging/removal techniques that minimize disturbance of the biosolids Preference to dewatering processes than minimize emissions, space requirements and can easily be covered Providing contract specifications that include odour control requirements such as equipment cover/containment

area(s), the use of odour masking agents, etc. Plan scheduling of decommissioning work during cold weather months, to the extent possible, to reduce the

potential of odour related construction issues, where feasible, which will require careful consideration of the condition of the supernatant, biosolids, and soil during winter conditions

7.1.1 Regulatory Compliance Overview

Incineration, agricultural land application and landfilling were considered potential options for disposal of biosolids from decommissioning of the lagoons. This section presents a summary of the regulations that will apply to the decommissioning activities and removal of the biosolids.

7.1.1.1 Incineration

The MOE administers waste management under Part V of the Environmental Protection Act (EPA), which prohibits the operation of a waste management system or waste disposal site or establishment without a C of A issued by MOE. Waste incinerators, which include Energy from Waste (EFW) facilities, are treated as final disposal sites and; as such, are subject to the normal approvals process. Information received from the Region indicated that the Region of Peel EFW facility, which incinerates non-hazardous solid waste for the purpose of producing energy, could be a possible disposal site for the biosolids from the lagoon decommissioning activities. However, the Region of Peel is not willing to accept any lagoon material due to the potential for contamination and presence of unwanted materials such as clay, stones, and debris that may have been deposited into the lagoon over time. Note that any soil materials hauled off-site for incineration will have to meet all the requirements of the C of A under which the EFW facility or incinerator is operating.

7.1.1.2 Land Application

In order to apply biosolids to an agricultural field, selected sites must be pre-approved by the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA). Biosolids testing must also be completed in accordance with the Nutrient Management Act (NMA) prior to leaving the WWTP or transfer station. Biosolids quality and location of site application are regulated by MOE under the Environmental Protection Act. The NMA (O. Reg. 267/03) was enacted in 2002, and was amended in 2009 as O. Reg. 338/09. The purpose of the NMA is to regulate and provide standards for (i) nutrient management plans; (ii) the agricultural land application of nutrients which include agricultural source material (manure, runoff from farm/animal yards, washwater from



agricultural operation, anaerobic digestion output, regulated compost, etc.) and NASM (pulp and paper biosolids, sewage biosolids, anaerobic digestion output, etc.); (iii) containment areas in farmland; (iv) quality of manure and (v) other wastes to be applied to land. It should be noted that the maximum land application rate (volume per 24-hour, 1 year, 5 years period etc.) for NASM, which includes Category 3 NASM (biosolids from sewage lagoon), is based on the concentrations of regulated parameters present in the agricultural field at the time of application, where the biosolids will be applied, and not necessarily on the quantity of NASM applied. The volumes of biosolids that are permitted to be applied to an agricultural field depends on the current conditions including depth to groundwater, distance to surface water, slope, soil characteristics, distance to drinking water supplies, and proximity to homes, schools and other establishments for each approved agricultural site. The NMA applies to the Region in regard to the sampling and analysis of the biosolids prior to hauling and land application. Biosolids from the lagoons must be sampled and analyzed for metals, nutrients and pathogens as stipulated in Section 98.0.4 (Sewage biosolids from lagoons) of the NMA. Within the main categories, there are metals categories (CM1 or CM2), pathogen categories (CP1 or CP2), and odour categories (OC1, OC2 or OC3). The biosolids from lagoons (Category 3 NASM) will also require sampling and analysis to determine pathogen levels, as listed in O. Reg. 338/09 Table 2 of Schedule 6 (CP1 NASM that is sewage biosolids or contains human body waste), or Table 3 of Schedule 6 (CP2 NASM). It is also noted that NASM whose odour detection threshold exceeds that of OC3 NASM will not be authorized for land application.

7.1.1.3 Landfilling

A viable option to managing the dewatered biosolids, clay liner, contaminated soils and other infrastructure associated with lagoons (booster pump station, yard piping, odour control equipment, pumps, etc.) is to dispose the materials at a MOE-licensed landfill facility designated to accept these wastes. Consideration of landfilling of the dewatered biosolids during lagoon decommissioning would be based on one or more of the following criteria: 1. The sampling results indicate the biosolids are not in compliance with the NMA 2. There is no land available for land application 3. The Region chooses to send the material to the landfill which would be consistent with current disposal

practices Disposing the materials at a landfill site falls under the requirements of O. Reg. 558/00 (as amended) of the Environmental Protection Act. Representative samples of the dewatered biosolids must be analyzed by a CALA accredited laboratory for the parameters listed in Schedule 4 of O. Reg. 558/00 in order to determine waste classification (e.g., non-hazardous/solid wastes versus hazardous wastes) for landfill disposal purposes. The results of these leachate tests will determine landfill disposal (O. Reg. 558/00, Schedule 4- Leachate Quality Criteria) and hauling requirements. The analysis is commonly referred to as a Toxicity Characteristic Leaching Procedure (TCLP) and includes completing a slump test. Additional bulk chemistry analysis may be required depending on the C of A requirements of the landfill receiver. This analysis will be required prior to decommissioning to assess the viability of landfilling the biosolids, clay liner, contaminated soil (berm materials), and other lagoon infrastructures (where applicable).

7.1.1.4 Soil and Groundwater Quality

O. Reg. 153/04 (as amended) governs soil and groundwater quality for use in assessing contaminated sites in Ontario. The regulation provides two approaches to assessing soil and groundwater quality on sites in Ontario:



1. The generic approach whereby the MOE has published a set of generic SCS that are considered to be protective of human health and the natural environment; and

2. The risk assessment approach which is used to develop property specific standards which incorporate site specific information concerning the conditions and characteristics of a specific property assessing potential risk to human and ecological receptors.

In order to assess the soil and groundwater data collected from the Site, current applicable MOE SCS have been used. The MOE Table 2 SCS for industrial/commercial/community land use in a potable groundwater condition are considered appropriate, as the Region uses groundwater for its municipal potable water supply. Furthermore, it is stipulated in O. Reg. 153/04 (as amended) that soil and groundwater quality samples collected within 30 m of the Grand River should be evaluated using the MOE Table 8 SCS. In some cases, contaminants at a site may be present at concentrations higher than generic soil and groundwater standards set out in O. Reg.153/04 (as amended). In these situations, a property owner may consider developing property-specific standards through the use and application of a risk assessment. A risk assessment scientifically examines the potential risk posed to humans, plants, wildlife and the natural environment from exposure to a contaminant. The purpose of a risk assessment is to develop property specific standards that will protect the uses that are being proposed to take place on the property. For the Site, a screening level ecological risk assessment should be considered to evaluate the potential risks to pertinent ecological receptors based on the levels of metal impacts identified in the clay liners underlying the lagoons. The screening level ecological risk assessment may also be used to assess soil impacts identified in the lagoon berms if excavation and off-site disposal of these materials is not deemed to be a viable option. AECOM understand that it is the Region’s intent that the findings of the risk assessment not be submitted to the MOE for review as per requirements in O. Reg. 153/04 (as amended), and would be used for their due diligence purposes only.

7.2 Lagoon Decommissioning Options

The management of the materials requires two steps: 1) processing of the materials and, 2) ultimate disposal of the processed materials. A range of processing and disposal options are available.

7.2.1 Processing Options

Following four (4) options were considered in processing biosolids during lagoon decommissioning activities: Liquefy biosolids and haul off-site as a liquid for disposal On-site mechanical dewatering, options for which are presented in Table 28 and off-site disposal Pump to the WWRMC and off-site disposal Addition of amendment (woodchips/sawdust mixture), excavation, and off-site disposal

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The advantages and disadvantages of each above-referenced process options for both the lagoons are presented in Table 29. Assessments of preferable options were based primarily on the feasibility, ability, potential odour generation, and duration/cost of each process option. It should be noted that with the exception of last option referenced above (addition of amendment), all other options will require liquefying of biosolids to create a pumpable material (with a minimum of 6 % solids content). It will be the Contractor’s responsibility to select the feasible options to complete the decommissioning activities on schedule, approximately 6 months (tentatively from January to June).

7.2.2 Disposal Options

The biosolids can be managed via following three disposal options, as applicable: Incineration Off-site land application Off-site disposal at MOE certified landfills

The advantages and disadvantages of each disposal option, including which options are feasible, are presented in Table 30. Preferable options were based primarily on the feasibility, ability, potential odour generation, duration, and associated cost of each process and disposal option.



Table 29 Biosolids and Soil Cover Process Option Advantages, Disadvantages and Feasibility Lagoon Advantages Disadvantages Feasible

Option?

Option: Liquefying Biosolids and Off-Site Disposal as a Liquid

1

Effluent from the Kitchener WWTP could be used to liquefy the biosolids

Depending on the quality and availability of land, liquid biosolids can be land applied

Liquefying process may be restricted in winter months due to freezing conditions; as such scheduling and duration of the decommissioning activities will be long

Potential for odour issues during liquefying, mixing, pumping and hauling operations

Significant quantity of liquid biosolids to be hauled off-site Significant liquid hauling vehicles in and out of the Site

mean increased traffic hazard The cost associated with this option is relatively high Liquefied biosolids can only be land applied

No

2

Option: On-Site Dewatering and Off-Site Disposal

1

On-site mobile dewatering of biosolids has been effectively implemented at the Site in the past

Less quantity of biosolids to be hauled off-site for disposal, and therefore less truck traffic in and out of the Site

Based on the duration of operation, decommissioning activities can be conducted in a relatively short duration

Depending on the quality, biosolids can be land applied, land filled and/ or incinerated.

This process requires re-liquefying of Lagoon 1 biosolids, thus a significant addition of water (Kitchener WWTP effluent)

Process water (filtrate) generated during dewatering operation will require pumping and treatment at the Kitchener WWTP and will be dependent on the capacity of the Kitchener WWTP

Polymer amendment will be required to aid in the dewatering process

Dewatering will be restricted in winter months due to freezing conditions; as such scheduling and duration of the decommissioning activities may be prolonged.

Mechanical dewatering system requires electric-power-service for its operations

Potential for medium to high odour issues during liquefying, mixing, pumping and hauling operations

The cost associated with this option is medium to high

Yes

2

Option: Dewatering at the WWRMC and Off-Site Disposal

1

Pumping liquefied lagoon biosolids to the WWRMC and dewatering are currently implemented at the Kitchener WWTP

Existing on-site infrastructure can be utilized. No biosolids to be hauled off-site for disposal from the

Site (assuming all biosolids can be pumped to the WWRMC)

No truck traffic hauling biosolids in and out of the Site Low odour emissions during operation and

decommissioning Depending on the quality, biosolids may be land

applied, landfilled or incinerated

This process requires re-liquefying of Lagoon 1 biosolids Possible biosolids pumping limitations during winter

months due to freezing conditions; as such prolonged pumping and decommissioning duration. Overall, medium to long decommissioning completion time

The capacity restrictions at the WWRMC mean prolonged scheduling and duration of the decommissioning activities

Pumping operation requires electric-power-service. Last few years prior to the WWRMC upgrade and

currently, the dewatered biosolids have been disposed of at a landfill

The cost associated with this option is medium

No

2 Yes

Option: Biosolids Amendment (Woodchips/Sawdust) and Off-Site Disposal

1

This process will not require dewatering of biosolids Lagoon 1 is currently partially dewatered; as such

minimal dewatering of supernatant is required at Lagoon 1

Ease of operation by adding amendment in the form of woodchips/sawdust mixture

Based on the duration of operation, decommissioning activities can be conducted in a relatively short duration

Decommissioning activities can be conducted in winter months; as such short schedule and quicker completion time

Winter excavation activities would reduce potential odour issues

Large quantity of supernatant in Lagoon 2 must be manually dewatered to create condition similar to Lagoon 1

Potential for medium to high odour issues during mixing, excavation and transportation operations.

Significant quantity of biosolids/amendment mixture to be hauled off-site for disposal

Significant truck traffic in and out of the Site mean increased traffic hazard

The cost associated with this option is medium to high Amended biosolids can only be land-filled

Yes

2 Yes



Table 30 Lagoon Biosolids and Impacted Berm Material Disposal Option Advantages, Disadvantages and Feasibility

Process Options Advantages Disadvantages Feasible Option?

Option: Incineration On-site dewatering of

biosolids via mechanical means.

Loading and transportation of dewatered biosolids for off-site disposal at an incineration or EFW facility

Incineration of dewatered biosolids at the Incinerator or EFW facility

Provided that the Incinerator or EFW facility accepts dewatered biosolids; incineration offers the potential for reducing the volume of biosolids (remnant ash) to be disposed of at a landfill

Possibly requires less regulatory compliance to incinerate dewatered biosolids provided EFW facility or Incinerator accepts metal impacted biosolids

Potential for medium to high odour issue during dewatering process and transportation of biosolids off-site for incineration

Dewatering of biosolids is a seasonal operation (not viable in the winter months), which could impact the overall schedule and duration of the decommissioning activities

Based on the quantity of biosolids to be processed on-site, quantities of dewatered biosolids (number of truck loads) to haul off-site, and trucking distance from Site to the Incinerator or EFW facility, the cost of disposal will range from medium to high

Approval from the receiving Incinerator or EFW facility to accept biosolids from the Region does not currently exist and therefore, co-ordination and approval would need to be granted.

Incinerations do not make beneficial use of the nutrients available in biosolids

Yes (If EFW/

Incineration facilities are

willing to accept

contaminated biosolids materials)

Option: Land Application Liquefying biosolids (by

adding effluent from Kitchener WWTP).

Pumping of liquefied biosolids and transportation for off-site disposal.

Land application of liquid biosolids.

Provided the quality of biosolids (liquid or dewatered) meet stringent regulatory requirements and assuming that land is available; biosolids can be applied in agricultural (farm) lands, forest areas, reclaimed lands, etc

Biosolids can be land applied in both liquid and solid state with or without subsequent incorporation into soil

Biosolids are composed of organic matter that promotes bacterial activity and improves soil characteristics, such as structure, texture, and water retention properties of soil

Land application of biosolids can be effective recycling option that benefits both generator (Kitchener WWTP) and users (farm lands)

Based on the quantity of biosolids, significant area will be required to land apply the biosolids. Note that the volume of biosolids that can be land applied is dependent on the soil conditions of receiving agricultural fields. Although the Region has indicated that minimal land is available for the application of biosolids, it is unlikely that the Region would have enough approved land to apply all the biosolids in the Lagoons during lagoon decommissioning activities.

Consideration for land application sites (both liquid and dewatered biosolids) include various restrictions such as depth to groundwater, distance to surface water, slope, soil characteristics, distance to drinking water supplies, and proximity to homes, schools and other establishments. As such, availability of suitable land for biosolids application may be an issue.

Based on the quality of biosolids (MTE Draft Report, January 2012) and stringent regulatory requirements (O. Reg. 338/09, amending O. Reg. 267/03), land application of biosolids appear unlikely for the less restrictive Table 1-CM1 NASM parameters; as such biosolids would need to applied to properties meeting Table 2 parameters.

Land application of biosolids is seasonal, and typically takes place between April and May, and September and October.

Biosolids cannot be applied during rainy season; as such biosolids application is weather dependent as well

Potential for medium (dewatered biosolids) to high (liquid biosolids) odour during loading transportation and land application of biosolids.

Based on the quantity of biosolids to be processed (liquefied or dewatered), hauled off-site for disposal, and trucking distance from Site to agricultural fields, the cost of land application will range from medium to high.

No

On-site dewatering of biosolids (via mechanical means).

Loading and transportation of dewatered biosolids for off-site disposal.

Land application of dewatered biosolids.

No



Process Options Advantages Disadvantages Feasible Option?

Option: Landfilling On-site mechanical

biosolids dewatering Loading and

transportation of dewatered biosolids and other excavated materials (including piping, equipment, pumps, etc.) for off-site disposal

Landfilling of materials at a MOE licensed landfill

Based on the subsurface investigation completed by MTE (January, 2012), quality of biosolids will likely meet O. Reg. 558/04 (amending O. Reg. 347/90) to be dispose of at a licensed landfill.

Landfilling criteria (administrative and regulatory requirements) are less stringent and restrictive.

Unlike land application sites, availability of landfill sites is less of an issue, and all excavated materials, including geotextile liner, yard piping, odour control equipment, contaminated berm soils etc., can be transported to and disposed of at the landfill facility.

Historically and at present majority of the biosolids from the lagoons have been landfilled.

Combined approach can be utilized to meet schedule requirements (i.e., more flexibility).

Decommissioning activities utilizing biosolids amendment could be performed during winter months.

Based on the large volumes of biosolids (dewatered or amended), several landfills may be required to dispose of the biosolids. Shipping biosolids out of province will require Region’s approval although it is not an option based on Region guidelines.

Although less stringent regulatory requirements; biosolids testing must be completed in accordance with the requirements of O. Reg. 558 (amending O. Reg. 347) prior to leaving the Site. Soil quality must be analyzed by a CALA accredited laboratory to determine waste classification, TCLP (leachate test) analysis will be required to determine landfill disposal and hauling requirements.

Based on the quantity of biosolids to be processed (dewatered or amended), excavation, loading and transportation, and hauling distance from Site to the landfill site(s); the overall cost of lagoon decommissioning could be high

Potential for medium to high odour during loading, transportation and land filling of biosolids

Based on the quantity of biosolids to be processed (dewatered or amended), hauled off-site for disposal, and trucking distance from Site to landfill sites, the cost of disposal will range from medium to high

Yes

Addition of woodchips/sawdust as an amendment to biosolids (no dewatering of biosolids)

Excavation of amended biosolids

Loading and transportation of amended biosolids and other excavated materials (including piping, equipment, pumps, etc.) for off-site disposal

Landfilling of all the materials at a MOE licensed landfill

Yes

7.3 Lagoon Decommissioning Design Assumptions

Several design assumptions have been considered in evaluating the decommissioning approach for the lagoons. The condition of the lagoons at the time of decommissioning (expected to begin in the fall of 2012) assumes the following: All biosolids material include the soil cover historically present at the base of the biosolids; Landfilling of the biosolids will meet O. Reg. 588/00 (amending O. Reg. 347/90) requirements for off-site

disposal Limited excavation and off-site disposal will be required for contaminated berm materials located in Lagoon 1

(north and northwest berms) Contaminated clay liners and soils in the berms in Lagoon 1 and Lagoon 2 will be assessed by a screening level

ecological risk assessment to confirm that there is no unacceptable ecological risk for use as backfill on the Site Lagoon 1 clay liner will be excavated and placed into Lagoon 2 and used for backfill/regrading Any infrastructure such as booster pumping station, pumps, yard piping, odour control equipment, etc.

associated with the lagoons will be decommissioned and removed from the Site; Based on the subsurface investigation results completed by MTE, the thickness, volumes, solid content and

density of supernatant, biosolids and soil cover, and the clay liner were estimated and are included in Table 31, Table 32, and Table 33

A verification sampling plan will be developed to confirm the removal of any contaminated materials within the berms

Odour control measures will be required during lagoon decommissioning activities



The Contractor will rely on the WWTP Operator (OCWA) to oversee the pumping of supernatant to the headworks. Pumping will be restricted to avoid impacts on WWTP operations with the rate dependant on actual plant performance at the time

Table 31 Estimated Volumes and Thicknesses of Supernatant in Lagoon 1 and Lagoon 2

Supernatant Estimated Existing Condition

Surface Area (m2) Thickness (m) Volume (m3) Solid Content (%) Density (kg/m3)

Lagoon 1 31,500 0.3 9,500 Not Applicable 1,000

Lagoon 2 24,100 1.8 42,200 Not Applicable 1,000

Table 32 Estimated Volumes and Thicknesses of Biosolids in Lagoon 1 and Lagoon 2

Biosolids and Soil Cover

Estimated Existing Condition Surface Area

(m2) Thickness (m) Volume(m3) Solid Content (%) Density (kg/m3) Tonnage

(tonne) Lagoon 1 31,500 1.5 47,300 18 1,100 50,000

Lagoon 2 24,100 2.3 54,200 10 1,000 56,000

Table 33 Estimated Volumes and Thicknesses of Clay Liner in Lagoon 1 and Lagoon 2

Clay Liner Estimated Existing Condition

Surface Area (m2) Thickness (m) Volume (m3) Solid Content

(%) Density (kg/m3) Tonnage (tonne)

Lagoon 1 31,500 1.0 31,500 Not Applicable 1,750 54,999

Lagoon 2 24,100 1.0 24,100 Not Applicable 1,750 42,079

7.4 Lagoon Decommissioning Plan

Decommissioning of the lagoons will consist of removing the following materials: Supernatant Biosolids (up to ~18% solids) Clay liner from Lagoon 1 only (~1 m thick) Contaminated soils [exceeding O.Reg.153/04 (as amended)] underlying and adjacent to the lagoons (portion of

northern berm) Geotextile liner from Lagoon 1 only Decommissioning of the Booster Pump Station Odour control equipment and piping (including yard pipes) currently surrounding the lagoons

The feasible approaches to handling the materials and the chronology of decommissioning activities are discussed in the following sections.

7.4.1.1 Planning and Site Preparation

Pre-planning includes preparation of required plans, specifications, and applicable permits to carry out the decommissioning activities. Site preparation will involve: Utility clearance survey to aid the existing utility plan Mobilization of equipment and personnel to the Site Designation of the work zone and laydown areas for temporary storage of equipment and materials Decontamination/washing areas for equipment and trucks Erosion control measures and groundwater/storm water management



Clearing and grubbing, where required.

7.4.2 Chronology of Activities

Based on the evaluation of above-mentioned process and disposal options, the following points provide the general chronology of lagoon decommissioning activities for each lagoon. Note that it will be the Contractor’s responsibility to select the feasible option (or combination of options) to complete the decommissioning activities on schedule and within the stipulated contract.

7.4.2.1 Lagoon 1

At Lagoon 1, one (1) and/or two (2) or a combination of the following options may be implemented by the selected Contractor awarded the work:

1. On-site dewatering (via mechanical means) and off-site disposal at licensed landfills

Liquefying biosolids and pumping to on-site dewatering system On-site dewatering of biosolids via mechanical means Loading and transportation of dewatered biosolids for off-site disposal Landfilling of the dewatered biosolids at MOE licensed landfills

2. Biosolids amendment with woodchips/sawdust and off-site disposal at licensed landfills

Pumping of supernatant to Lagoon 2 (and ultimately to WWTP headworks at a controlled rate by the WWTP

operator) Construction of access ramp/road within Lagoon 1 Addition of woodchips/sawdust as an amendment to biosolids (no dewatering of biosolids) Excavation of amended biosolids Loading and transportation of amended biosolids and other excavated materials for off-site disposal Landfilling of all materials at MOE licensed landfills

7.4.2.2 Lagoon 2

At Lagoon 2, a combination of the following three (3) options may be implemented, and as selected by the Contractor awarded the work:

1. Pump to the WWRMC, dewater (via mechanical means), and off-site disposal

Liquefying biosolids and pumping to on-site dewatering system Pump to the WWRMC and dewatering of biosolids (via centrifuge) under the oversight of the WWTP Operator. Loading and transportation of dewatered biosolids for off-site disposal (potentially licensed landfills)

2. On-site dewatering (via mechanical means) and off-site disposal at licensed landfills

Liquefying biosolids and pumping to on-site dewatering system On-site dewatering of biosolids via mechanical means Loading and transportation of dewatered biosolids for off-site disposal Landfilling of the materials at MOE licensed landfills



3. Biosolids amendment with woodchips/sawdust and off-site disposal at licensed landfills; this process requires pumping of supernatant to WWTP headworks

Pumping of supernatant to WWTP headworks at a controlled rate under the management of the WWTP

operator Allow biosolids to naturally dewater to 15-20% solids, “windrowing” to improve dewatering Addition of woodchips/sawdust as an amendment to biosolids (no dewatering of biosolids) Excavation of amended biosolids Loading and transportation of amended biosolids for off-site disposal Landfilling of the materials at MOE licensed landfills

Following the removal of biosolids from Lagoon 1 and Lagoon 2, final steps to decommissioning will include the following: Removal of the clay liner in Lagoon 1 and reusing the clay in Lagoon 2 as backfill Removal of contaminated soils and clay liner (Lagoon 1) in selected areas with off-site disposal in an MOE

licensed landfill Removal of all existing infrastructure including the booster pump station located south of Lagoon 1 The potential construction of a storm water management pond within the footprint of Lagoon 2 at the

southeastern corner During the decommissioning of lagoons, environmental monitoring and sampling will occur and include the following: Odour monitoring and control Noise monitoring and control (if applicable) Storm water management Erosion control Sampling of dewatered biosolids to determine appropriate disposal site (land application or landfilling) Sampling of excavated berm materials to determine appropriate disposal site Decontamination and/or washing of heavy equipment and trucks prior to leaving the Site

7.4.3 Infrastructure

Several components of the Kitchener WWTP’s infrastructure will be utilized during the decommissioning of the lagoons. The infrastructure currently on-site that may be used contingent on the selected options from the Contractor awarded the work is as follows: Access roadways for off-site transport Water supply (WWTP effluent) to liquefy biosolids and for decontamination/washing Site electrical and lighting

7.4.4 Site Laydown Area and Temporary Storage

The Site is an active WWTP with several upgrades taking place and there is limited space available for the storage of equipment and materials for the lagoon decommissioning activities; as such, portion of southern berm immediately adjacent to Lagoon 1, just east of booster pump station and southern portion of Lagoon 1 are proposed to be utilized as the Site laydown/staging areas. The Region will occupy the Site and existing building(s) during the duration of the decommissioning activities of the lagoons. There is a current construction contract that abuts Lagoon 1 and encompasses the road between the



primary clarifiers and the Plant 2 aeration tanks. Therefore, the Contractor awarded the decommissioning contract must follow the following protocols: Co-operate with the Region during the entire decommissioning operations to minimize conflicts and facilitate the

Region’s day to day operations Work will be performed so as not to interfere with the Kitchener WWTP’s day-to-day operations Closing or obstructions of walkways, corridors, or other occupied or used facilities will be prohibited without

written permission from the Regions Kitchener WWTP operators and approval of authorities having jurisdiction; Maintain existing entrance/exits unless otherwise indicated Maintain access to existing walkways, corridors, and other adjacent occupied or used facilities; and Notify

Tenant/Owner in advance of activities that will affect Tenant/Owner operations Co-operate with the Plant 2 Construction Contractor (King City) during the entire decommissioning operations to

minimize conflicts and facilitate the Region’s usage Maintain time and/or space separation between Plant 2 Construction Contractor (King City) to ensure

Constructor status remains with the Contractors and is not imposed on the Region

7.4.5 Dewatering

7.4.5.1 Supernatant

The supernatant has historically been pumped to the Kitchener WWTP periodically, to ensure lagoons are not overfilled due to snowmelt, rainfall accumulation, surface runoff, etc. The Contractor will require mobile pumps for transfer of supernatant from Lagoon 1 into Lagoon 2. The Contractor will rely on the WWTP Operator (OCWA) to oversee the pumping of supernatant from Lagoon 2 to the headworks. Pumping will be restricted to avoid impacts on WWTP operations with the rate dependant on actual plant performance at the time. The range of pumping flows is expected to be in the range of 200 to 500 m3/d.

7.4.5.2 Lagoon 1

Both Lagoon decommissioning options will require the pumping of supernatant/rainwater to the Kitchener WWTP Headworks Building. No centrate pumping is required if the use of a biosolids amendment is used for biosolids processing. The supernatant in Lagoon 1 was pumped to Lagoon 2 and ultimately to the WWTP to facilitate construction of the new Blower Building for the Plant 2 upgrade project. The current approximately 0.3 m (9,500 m3) is the result of accumulated rain and snow melt and would have to be pumped to either Lagoon 2 or the WWTP headworks, at the time of decommissioning. The actual amount of supernatant in Lagoon 1 at the time of decommissioning will be weather dependant.

7.4.5.3 Lagoon 2

All three (3) options available for Lagoon 2 decommissioning would require supernatant/centrate pumping to Kitchener WWTP headworks facility. Based on MTE’s subsurface investigation report, it is estimated that approximately 42,200 m3 of supernatant (based on average depth of 1.8 m standing water) is present in Lagoon 2.



7.4.6 Dredging/Dewatering of Biosolids

7.4.6.1 Lagoon 1

One (1) of the two (2) feasible options for decommissioning of Lagoon 1 is: On-site dewatering (via mechanical means) and off-site disposal at licensed landfills. This option includes liquefying biosolids by adding Kitchener WWTP effluent, dredging biosolids to the base of the lagoon, and pumping to the on-site dewatering facility. As the Kitchener WWTP has the experience with pumping the liquefied biosolids to the on-site dewatering facility with respect to timing, rate, concentration, treatability, etc., it is assumed that the same approach would be utilized for the lagoon decommissioning phase.

7.4.6.2 Lagoon 2

Two (2) options are considered feasible that would require removal of pumpable biosolids by dredging biosolids to the base of the lagoon and pumping to the WWRMC or on-site dewatering facility for biosolids in Lagoon 2: Option 1: Pump to Manitou Drive WWRMC, dewater (via centrifuge) and off-site disposal at licensed

landfills Option 2: On-site dewatering (via mechanical means) and off-site disposal at licensed landfills

The aforementioned options are the preferred options and are based on biosolids concentrations being above the applicable O. Reg. 338/09 (amending O. Reg. 267/03) standards for selected metal parameters. In addition there would be minimal truck traffic, odour generated can be managed, and infrastructure for this operation is already currently being utilized. The existing pumping station would be utilized. Pumping of the Lagoon 2 biosolids appears unlikely due to capacity limitation at the WWRMC and access to biosolids materials within the lagoon. As such the following option could also be utilized in removing about 25% of the biosolids that are not easily accessible from Lagoon 2: Biosolids amendment with woodchips/sawdust and off-site disposal at certified landfills

7.4.7 Excavation

At both the lagoons, excavation will be required only when utilizing biosolids amendment with woodchips/sawdust as the option in decommissioning lagoons. This option will consist of the addition of woodchips/sawdust as an amendment to the biosolids, and excavating the amended biosolids for off-site disposal. During excavation, materials from the lagoons will be contained within the berms of the existing lagoons and a temporary dam (where necessary), to contain surface water accumulation. At minimum, the excavation procedure would include the following tasks: Excavation will be in accordance with the final grading drawings and to the appropriate depth Excavation and removal of materials will be via mechanical means (excavator, loaders, dump trucks, etc.) Stockpiling of excavated materials, if and when required, will be done in a way as not to interfere with other work

being performed at the Site All uncovered excavations will be secured by fencing or other means at the end of each work day Access ramp will be created by placing the clean fill (sand and gravel) at the southwest corner of Lagoon 1,

which will be used as the ingress/egress point for the construction equipment and heavy container trucks throughout the decommissioning (excavation) of lagoons



7.4.7.1 Biosolids/Soil Cover/Clay Liner/Berm Material

7.4.7.1.1 Lagoon 1

At Lagoon 1, the following layers, including the berms (at select locations), will be excavated: Biosolids The clay liner (~1 m thick) to be placed in Lagoon 2 (except for highly contaminated clay liner assumed to be

present at the northwest corner of Lagoon 1, which will be disposed of off-site 1) Removal of the non-woven geotextile liner Sampling in areas where excavation is planned will be completed prior to commencing excavation. All samples

will be submitted to and accredited CALA laboratory to determine if the excavated materials can be land applied or disposed of at an approved landfill

Prior to commencing excavation, materials will be tested for consistency and flowability in the form of in situ slump test. The aforementioned slump test will be conducted as per Schedule 5 (Test method for the determination of liquid waste (slump test)) of O. Reg. 558/00 and is proposed to determine if the excavated materials can be hauled off-site in covered dump trucks as solid material

Upon removal of the biosolids, an area within Lagoon 1 will be partially excavated and a ramp will be created by placing the clean fill (sand and gravel) at the southwest corner of Lagoon 1, which will be used as the ingress/egress point for the construction equipment and heavy container trucks throughout the excavation of Lagoon 1 (Figure X-010)

7.4.7.1.2 Lagoon 2

At Lagoon 2, the following layers, including berms at select locations, will be excavated and/or managed: Biosolids The eastern portion of Lagoon 2 may be utilized as a storm water management pond After pumping supernatant and biosolids materials and prior to excavation, the northeast section of existing

berm/road separating Lagoon 1 and Lagoon 2 will be removed to allow for construction vehicles and equipment in and out of Lagoon 2, and into Lagoon 1. The aforementioned ramp at the southwest corner of Lagoon will be utilized as the ingress/egress point for the construction equipment and covered dump trucks throughout the excavation of amended biosolids in Lagoon 2

Excavated materials will be sampled and submitted to the CALA accredited laboratory for analysis to determine if the excavated materials can be disposed of at an approved MOE licensed landfill facility

Excavated materials will be tested for consistency and flowability in the form of in situ slump test to determine if the excavated materials can be hauled off-site in dump truck as solid material

The contaminated soils identified within the northern berm of Lagoon 1 and Lagoon 2, and northwest portion of Lagoon 1 will be excavated and confirmatory sampling and analyses will be conducted. Based on several contaminants of concern (PHC, PAH, PCB and metals) detected in a sample collected from MW1-11 at 4.6 to 5.2 mbgs (compared to a sample from MW2-11 from the same depth), it is estimated that the extent of contamination at the northwest portion of Lagoon 1, and adjacent berm materials is higher than other areas in and around Lagoon 1. A temporary berm will be required to separate the contaminated biosolids materials from the remaining biosolids; these materials may require separate disposal and would require a different verification program. This temporary berm will also help to contain water accumulation during excavation, and prevent the mobility of contaminants to other areas of Lagoon 1.



7.4.7.2 Materials Beneath the Lagoons

Soil quality information directly beneath the lagoons will not be assessed until lagoon excavation activities begin, as the clay liner was not allowed to be punctured during the subsurface investigation completed by MTE in and around the lagoons. Historical borehole logs (CANVIRO, 1986 and Naylor, 1988) were utilized to determine the soil stratigraphy directly beneath the lagoons. A plan to sample, analyze and handle the material will be incorporated into the construction phase of the lagoon decommissioning project. Management options for any impacted soil materials beneath the lagoons will be the same as the clay liner (via screening level ecological risk assessment) and excess berm materials (excavation and off-site disposal).

7.4.7.3 Yard Piping and Booster Pump Station

Yard piping is present at various locations in and around the lagoons to pump biosolids from the lagoons to the WWRMC. Removal of the yard piping will be included in the General Contractor’s scope of work for the lagoon decommissioning activities. A booster pump station, located southwest of Lagoon 1 by the existing entrance/exit of the Site, along with the associated mechanical and electrical components will be decommissioned as part of the Contractor’s scope of work as well. AECOM will work with the Region to identify the components that require removal and the sections that can be cut, capped and remain in place. Note that the existing biosolids booster station cannot be decommissioned (demolished) until such time as the new sludge transfer pumping system has been commissioned and put into routine service.

7.4.8 Water Management During Excavation

Both the lagoons are situated within the floodplains of Grand River; therefore, it is anticipated that removal of supernatant, biosolids and clay liner from the lagoons will likely disrupt the existing pressure balance between the aforementioned layers and the upward pressure exerted on the base of the lagoons by groundwater (hydrostatic pressure force, buoyancy forces etc.) resulting in the possible migration of groundwater from the Grand River at flood levels into the lagoons. Any water accumulated (storm water and/or groundwater) during the decommissioning activities will require testing to confirm disposal options. If water is collected from areas where biosolids have already been removed, disposal to surface water bodies may be possible. However, if water is collected from within biosolids materials or areas of contamination, water will have to be pumped to the Kitchener WWTP headworks. Pumping will be undertaken using the pumps and discharge piping available at the Kitchener WWTP (assuming the Kitchener WWTP influent intake capacity is not exceeded) or discharging to the Grand River by using holding tanks for sedimentation (solid settling) followed by filtration (if required). However, no water collected and/or pumped during decommissioning activities will be discharged to the ground surface or nearby water bodies (including the Grand River) without proper assessment and/or treatment to ensure water quality meets regulatory requirements.

7.4.9 Erosion Control During Excavation

Erosion control (also known as soil stabilization) is a measure that is designed to prevent soil particles from being transported in storm water runoff. Erosion control best management practices (BMPs) protect the soil surface by covering and/or binding soil particles. The decommissioning activities (where applicable) will incorporate temporary erosion control measures as needed, and at minimum will implement the following practices: Schedule and stage work to reduce the amount and duration of soil exposed to erosion at any one time



Apply temporary erosion control to active and non-active areas as required by the construction site BMPs, such as the use of erosion control mats and/or wood mulching etc

Sediment controls are structural measures that are intended to complement and enhance erosion control measures and reduce sediment discharges from construction areas. Sediment controls are designed to intercept and settle out soil particles that have been detached and transported by the force of water. Locations of temporary sediment control BMPs will be determined in the field based on the conditions found. The following sediment controls or any suitable combination of these controls may be used: Silt fence Fiber rolls Straw bale barrier

The decommissioning activities will incorporate temporary sediment control requirements, and other measures as deemed necessary.

7.4.10 Noise Control

Noise levels will be controlled in accordance with the applicable local by-laws and the MOE Standards. In addition, normal decommissioning activities will take place five (5) days per week from Monday through Friday between 7:00 am to 7:00 pm to avoid disturbances to the nearby residence during after-hours. It should be noted permission to work on Saturdays may be obtained from the City of Kitchener. Noise requirements will be confirmed with the Region prior to final design/decommissioning activities.

7.4.11 Transportation and Disposal of Excavated Material

Excavated soil materials will be transported and disposed in accordance with all applicable federal, provincial, and/or local requirements and regulations. Landfilling is the most feasible option based on the evaluation of disposal options in terms of feasibility, process ability, odour generation, duration of completion and cost. The Contractor will be responsible for obtaining all applicable permits required for transportation and disposal of the excavated soil, with the exception of permits obtained by the owner and/or engineer.

7.4.12 Decontamination/Wash Pads

Temporary decontamination pads will be constructed just east of the ingress/egress ramp within Lagoon 1. The decontamination pads will be bermed and sloped such that decontamination/wash water may be collected and pumped for on-site treatment. Water generated during decontamination activities will be collected and pumped to the headworks of the Kitchener WWTP. Typically, decontamination will include washing of dump trucks, construction equipment, any machinery with a high pressure hose, as needed, prior to leaving the excavation area and/or the Site. Water will be supplied by the Kitchener WWTP. The use of plant service water for decontamination will be evaluated during detailed design. Decontamination pads will also be utilized to clean field sampling equipment and Site personnel (if required). Decontamination pads will be sized to fully contain the largest equipment used on-site.

7.4.13 Backfilling and Re-grading

Lagoon 1 will require minimal backfilling and grading of existing materials after the decommissioning activities. The final lagoon backfilling and grading will be addressed in the Plant 3 Construction, as new aeration tanks and new secondary clarifiers are proposed within the existing footprint of Lagoon 1.



Lagoon 2 will require significant backfilling and grading. Clay that is removed from Lagoon 1 (estimated to be approximately 31,500 m3) will be placed in Lagoon 2 and re-graded. In addition, approximately 10,000 m3 of granular fill and 10,000 m3 of topsoil will be required to complete a grading plan which is based on a slope rising towards the Lagoon 2 berm adjacent to the Grand River (from the northeast to the southwest of the lagoon). The southeast portion of Lagoon 2 may be used for the construction of storm water management pond and will not be backfilled.

7.5 Site Survey

A final site survey will be conducted at the completion of the Site upgrades.

7.6 Odour Control

7.6.1.1 General Description

The lagoon decommissioning will require the transportation, dewatering, conditioning and excavation of lagoon materials and equipment. Because the lagoons are historically a high emitter of odourous compounds, any disturbance during decommissioning has the potential to periodically emit high concentrations of odour. The impacts associated with these activities have been examined and specific mitigation measures will be implemented. To minimize the release of emissions, best practises and emission controls will be implemented as required and will include the following: Maintaining existing odour masking equipment Limiting the work area exposure, disturbed areas and number of crews Covering stored materials and material hauling vehicles Maintaining an effluent water cap whenever possible Preference to dredging/removal techniques that minimize sludge disturbance Preference to dewatering processes to those that minimize emissions, space requirements and can easily be

covered Scheduling dewatering activities during the coldest months (October through March), where possible Covering active work areas with controls (e.g., agents and tarps) during inactive periods Providing contract specifications that include odour control requirements Eliminating or minimizing the stockpiling of excavated materials Including specific requirements in the Contract Documents to cease operations if odours cause an unacceptable

impact on residents Based on the recommendations from CH2M HILL (2008), AECOM recommends the use of hydrogen peroxide during lagoon decommissioning. The use of lime can also be considered. Based on the findings of the past studies (XCG, 2007 and CH2M HILL, 2008), lagoon decommissioning should take place in the period from October to May, to the extent possible, in order to minimize odour emissions to the extent possible. In addition, scheduling should ensure that truck traffic is minimized through the surrounding neighbourhoods. Careful consideration of construction sequencing and scheduling should be undertaken to ensure that emissions due to construction equipment (i.e., NOx, PM10, PM2.5) are minimized during periods when the MOE issues an Air Quality Advisory.

7.6.1.2 Sampling of Excavated Materials

Sludge and soil sampling will occur during each stage of Lagoon Decommissioning. The sludge and soil samples should be analyzed for compounds known to cause odour (and consistent with the 2008 CH2M Hill Study).



VOCs will be analyzed for media classification (non-hazardous/hazardous). Results of this sampling program will be used to determine the most appropriate odour mitigation and treatment measures, contaminants of concern, real-time monitoring parameters and odour control technologies. Predictive odour emission modelling could also be performed to estimate the emissions and downwind impacts.

7.6.1.3 Real Time Monitoring

Real time monitoring is proposed to provide immediate air quality data from site decommissioning activities so that the necessary actions to reduce on-site emissions at the source(s) can be taken. Based on the historical data a preliminary monitoring program is outlined below. The requirements will change as the decommissioning design progresses and pending any regulatory input from the MOE. During all pumping, dewatering, dredging and excavation operations, real time air monitoring at regular intervals will be conducted using hand held mobile measurement devices. The location of sampling will be co-ordinated with meteorology data provided by the on-site meteorology station. Sampling locations will be agreed upon (by the Design Engineer, Region staff, MOE and Contractor) prior to the start of decommissioning activities and reviewed daily. Sampling will occur downwind of the decommissioning activity underway Record keeping practises should ensure that data is readily available for inspection by the MOE. In addition, the real time monitoring procedure should ensure that it is tied to the Community Complaints process such that direct correlation between measured events and complaints can be made. An “Action Plan” will be developed in the case of high compound levels (or exceedances). This action plan may include steps such as: 1. stopping work; 2. increasing the use of odour masking substances; and 3. using oxidants such as hydrogen peroxide, ferric chloride etc. The “Action Plan” will also contain a list of parties to be notified at each “Action Level”. These parties should include the Design Engineer, Region staff, Contractor, Regulator (MOE) and the public. Upon exceedance of relevant guidelines and standards, the monitoring results will be thoroughly analyzed and a full report with interpretation of results provided within 30 days after the event is initially documented.

7.7 Construction

7.7.1 Constructability

7.7.1.1 Data Gap and Field Sampling Plan

Field Sampling Plan during lagoon excavation will be developed during detailed design with approval from the Region.

7.7.1.2 Environmental Protection Plan

Environmental Protection Plan for lagoon decommissioning activities will be developed during detailed design.

7.7.1.3 Decommissioning Schedule

Decommissioning schedule will be developed during detailed design.



8. Digested Sludge Transfer Pumping (Contract 1b) 8.1 Existing Digested Sludge Transfer Pumping System

The Kitchener WWTP digested sludge transfer pumps were originally installed to transfer digested sludge from the secondary digesters to the on-site digested sludge storage lagoons. The digested sludge was transferred, seasonally, from the lagoons, to the off-site WWRMC (approximately 2 km away) using a dredge system and high pressure booster pumps. The Region stopped using the on-site sludge storage lagoons in 2010 to reduce plant odour generation. The digested sludge transfer pumps currently discharge directly to the suction of the booster pumps, which limits the system capacity. Given the plans to decommission and demolish the sludge storage lagoons and associated booster pumping system, the digested sludge transfer pumps will be required to pump digested sludge directly from the secondary digester to the WWRMC holding tank.

8.2 General Description

During Site Wide Facility Plan development, it was determined that the existing digested sludge transfer pumping system was not capable of pumping digested sludge from the secondary digester directly to the WWRMC due to: Limited capacity to maintain flushing velocity in the transmission main (existing pump capacity is 20 L/s and

required pump flushing capacity of 80L/s minimum) Limited total dynamic head (TDH) (existing pump TDH is 28m and required pump TDH of >65m) Undersized on-site piping for the required flow, particularly suction piping

To address the deficiencies identified, the digested sludge transfer pumping upgrades will include the following elements:

One (1) of the existing secondary digesters will be retrofitted and used for a combination secondary

digester/intermediate digested sludge storage tank Existing digested sludge transfer pumps will be replaced with two (1 duty, 1 standby) new pumps rated at 80 L/s

and 65m TDH New suction and discharge piping to suit the new operating requirements Surge protection system Automatic control of pump operation, based on sludge levels in the secondary digester tank and the WWRMC

holding tank New transmission main/connection from the digested sludge transfer pump station to the distribution chamber

housing the existing transmission main from the Kitchener WWTP to the WWRMC New electrical service, MCC and distribution Additional HVAC equipment

A simplified schematic of the digested sludge transfer system is presented in Figure 10.



Figure 10 Simplified Process Flow Schematic of the Digested Sludge Transfer System

Digested sludge transfer drawings (Series 200) are contained in Appendix A. The preliminary process control narratives and process and mechanical equipment lists are presented in Appendix J and K, respectively.

8.3 Process Design

8.3.1 Design Criteria

Table 34 presents process design criteria for the new digested sludge transfer pumps. Table 34 Digested Sludge Transfer Pumps Design Criteria

Parameter Value

Average Digested Sludge Production1 768 m3/d

Average Digested Sludge Production2 993 m3/d

Peak Digested Sludge Production2 1,393 m3/d

Maximum Pumping Hours per Day 8 hr

Minimum Pumping Days per Week 4 day Notes:

1. Current Conditions (OCWA, Compiled May 2008-June 2010) 2. 2Year 2041-PDM-4 (Peak Factor = 1.4)

8.3.2 Preliminary Design Specifications

Table 35 presents design specifications for the new Digested Sludge Transfer Pump Station, which is to be located in the existing Administration Building.



Table 35 Design Specifications for Digested Sludge Transfer Pump and Surge Protection Systems Item Specification

Pumps

Total No. 2 (1 duty, 1 standby)

Type Centrifugal Dry pit

Design capacity per pump 80 l/s (6.9 MLD)

Duty Point 80 L/s @ 65 m TDH

Motor size per pump 112 kW

Inlet / Outlet 250/150 mm

Surge Relief Tank Total No. 1

Volume 8 m3

Air Compressor

Total No. 2 (1 duty, 1 standby)

Capacity per compressor 30.6 m3/hr at 1206 kPa

Motor size per compressor 3.72 kW

Water Pump

Total No. 1

Capacity per pump 0.4-0.96 m3/hr at 1860 kPa (max.)

Motor size 1.5 kW

Surge Relief Valve Overflow Pipe 150 mm

Overflow Wet Well (Existing –Review for Detailed Design)

Dimensions (Lx W) 3000 m x 1500 m

Operating Level Variation 2200 m

Standby power requirements Total required emergency power capacity 1 duty pump plus surge protection equipment

8.3.3 Operating Philosophy, Instrumentation and Controls

The main purpose of the digested sludge transfer pumping system is to transfer digested sludge generated at the Kitchener WWTP to the WWRMC. The system will be semi-automatic: pump control will use operator input and SCADA automation at the Digested Sludge Transfer Pump Station and the WWRMC based on sludge levels in the secondary clarifier, pump controls, WWRMC holding tank level, and operator availability. Since the WWRMC dewatering process is essentially a batch process (1 shift per day, 5 days per week), it will be necessary for the Kitchener WWTP and WWRMC operators to communicate on a daily basis to establish the desired pumping scenario, based on reducing the level in the secondary digester while ensuring sufficient operating volumes for the WWRMC. Once the operation basis has been established, the WWTP will govern pump operation. A high level in the receiving tank will automatically shut down the sludge transfer pump and send a signal to the Kitchener WWTP SCADA system. On low level in the secondary digester, the duty sludge transfer pump will be stopped and an alarm sent to the Kitchener WWTP SCADA system. It should be noted that until the secondary digester modifications are implemented under Contract 2b, the operating level within the tank will be restricted to approximately 1.5 m of variation. The digested sludge flow rate will be continuously monitored by the flow meter installed on the digested sludge pump common discharge header. Each pump local control panel (LCP) will be equipped with a timer to record the duration of pump operation. It is expected that pumping will take place between 4 to 8 hours per day, 5 days per week.

8.3.3.1 Digested Sludge Transfer Pumps

The control objective of digested sludge transfer pumping is to control the liquid level of the secondary digester at the Kitchener WWTP and control the feed rate of digested sludge from the secondary digester to the WWRMC holding tank by controlling the speed and duration of operation of the duty digested sludge transfer pump.



The digested sludge transfer pumps will be started and stopped to provide the desired quantity of digested sludge to the WWRMC holding tank as set by the operator. The pump will shut down automatically when a pre-set high level is reached in the WWRMC holding tank and an alarm is generated or a low level is achieved in the Secondary Digester. The WWRMC operator will be able to stop the digested sludge transfer pumps from SCADA. The pump will be able to be started locally with no restriction; however, the pump will shut down at a pre-set high level in the WWRMC holding tank or a low level is achieved in the Secondary Digester. The WWRMC holding tank level will be displayed near the pumps. In the event of pump failure, there will be automatic switchover to the standby pump and an alarm will be issued to notified operators. The PLC monitoring the secondary digester and transfer pumps will reside at the Kitchener WWTP. The PLC monitoring the level transmitters in the WWRMC holding tank will reside at the WWRMC. The PLCs will communicate via fibre optic cable/ethernet network.

8.3.3.2 Surge Relief System

A surge relief system will be provided to control surges and the development of vacuum conditions within the transmission main during pump start-up and shut-down. A “packaged” system consisting of hydropneumatic (surge) tank, air compressor and water pump with a dedicated controller will be used. The controller will maintain the level in the hydro-pneumatic (surge) tank by reading the level and injecting or relieving air as appropriate to maintain a set level. System operation will be pre-programmed and will not require operator input. The air pressure in the tank will be monitored and the liquid level will be able to be read by the operator from the pressure gauge. A trickle (2 l/s) of water will be introduced into the tank by the water injection pump, which will run continuously into the force main to constantly flush the chamber free of solids and prevent gas from forming, which would have to be vented. The surge tank system will be controlled automatically through the LCP with no operator interaction. Only run status and alarms will be relayed to Kitchener WWTP SCADA.

8.4 Digested Sludge Transfer Piping

8.4.1 Design Alternatives

The nature of the digested sludge to be transferred from the Kitchener WWTP to the WWRMC will change over the course of the Kitchener WWTP upgrades, over three (3) phases: 1. Current: Sludge is co-thickened (1 - 3% solids) and fed to the digesters, resulting in digested sludge at 1 - 2%

solids pumped to WWRMC 2. Interim: WAS is mechanically thickened (to 4 - 6% solids) and combined with primary sludge (at 3% solids) and

fed to the digesters, resulting in digested sludge at 2 - 3% solids pumped to WWRMC 3. Long-term: Both WAS and primary sludge is mechanically thickened (to 4 - 6% solids) and fed to the digesters,

resulting in digested sludge at 3 - 4% solids pumped to WWRMC The main impact of sludge solids concentration is on headlosses in suction and discharge pipes. The existing suction piping had previously been identified as a concern, given the higher capacity and sludge concentration. To reflect the digested sludge concentrations that will be handled by the digested sludge transfer pumps over the course of the Kitchener WWTP upgrades, available NPSH was calculated for the following solids content levels: up to 1%, 2%, and 4%. Based on preliminary pump selection, a minimum NPSH of 6 m is required to ensure pump operation. Three (3) pipe replacement alternatives were considered to accommodate the pumping digested sludge directly from the secondary digester to the WWRMC holding tank at all plant upgrade phases and associated digested sludge solids content characteristics. The existing digested sludge transfer pumping suction piping consists of three (3) sections:



1. Digester Complex Piping: associated with the secondary digester and valve chamber 2. Yard Piping: connects the secondary digester and the Digested Sludge Transfer Pump Station 3. Digested Sludge Transfer Pump Station: within the Digested Sludge Transfer Pump Station

8.4.1.1 Option 1: Keep All Existing Suction Piping As Is

Option 1 is to keep all existing digester complex, yard, and digested sludge transfer station suction piping as is. Based on the NPSH data presented in Table 36, the existing suction pipe sizes are inadequate under almost all pumping scenarios. Table 36 Available NPSH for Digested Sludge Transfer Piping Option 1

Solids Content Pump Capacity (l/s) Min. NPSH Available (m) Max. NPSH Available (m)

Up to 1%

80

7 10

2% 51 8

4% 21 51 Note:

1. Insufficient to meet minimum NPSH requirement of 6 m

8.4.1.2 Option 2: Replace Yard Piping and Keep Digester Complex and Digested Sludge Transfer Pump Station Piping As Is

Option 2 is to keep the existing suction piping in the digester complex and digested sludge transfer pump piping and provide new yard piping. This option minimizes the complexity and cost of pipe replacement. Based on the NPSH data presented in Table 37, replacing the yard piping with larger diameter pipe will allow digested sludge transfer to the WWRMC for up to the interim condition under most scenarios; but may have limitations in maintaining pumping in the long-term, when both WAS and primary sludge is thickened. Table 37 Available NPSH for Digested Sludge Transfer Piping Option 2

Solids Content Pump Capacity (litre/sec)

Min. NPSH Available (m) Max. NPSH Available (m)

Up to 1%

80

9 13

2% 8 12

4% 7 11 Note:

1. Insufficient to meet minimum NPSH requirement of 6 m

8.4.1.3 Option 3: Replace Yard and Digester Complex Piping and Flowmeter in the Pump Room

Option 3 is to replace all of the existing suction piping. Based on the NPSH data presented in Table 38, Option 3 will allow digested sludge pumping under the three (3) scenarios considered. Table 38 Available NPSH for Digested Sludge Transfer Piping Option 3

Solids Content Pump Capacity (litre/sec)

Min. NPSH Available (m) Max. NPSH Available (m)

Up to 1%

80

11 14

2% 10 13

4% 9 12



8.4.2 Design Basis

Only Option 3 addresses all of the operating conditions. The design includes removal of all 200 mm diameter pump suction piping from the flange adjacent to the Secondary Digester No.3 to

the pump inlets; removal of the existing 20 L/s sludge transfer pumps; removal of the discharge pipe from the pump to the elbow above the vertical section immediately before the pipe

leaves the building; installation of two (2) new 80 L/s variable speed sludge transfer pumps; installation of new 200 mm diameter discharge pipe, including valves and 200 mm diameter magnetic flow meter

from the pumps, with the horizontal section at a lower elevation to facilitate access to the PRV; installation of a 200 mm PRV, with relief to existing wet well; installation of packaged hydraulic surge control system; removal of existing 200 mm diameter yard piping from Administration Building to yard chamber and installation

of blind flange in chamber; installation of new 200 mm x 300mm wye connection in yard; installation of new 300 mm diameter ductile iron force main from just outside Administration Building to

abandoned Diversion Chamber which houses force main from site to the WWRMC; and installation of transition wye from ductile iron to HDPE pipe complete with isolation valve.

Replacement of the suction pipe within the digester itself would be completed under the Anaerobic Digestion contract, presented in Section 9.

8.5 Architectural and Structural Design

Not applicable.

8.6 Building Mechanical Design

8.6.1 Heating, Ventilation and Air Conditioning

Indoor design conditions are summarized in Table 39. Table 39 Indoor Design Criteria for Digested Sludge Transfer Pumping

Areas Criteria

Pump Room 5~10 °C unoccupied mode and 18 °C for occupied mode (winter) / 5.5 °C above outdoor temperature (summer)

Electrical Room 27 °C (summer) / 18 °C (winter)

8.6.1.1 Existing Ventilation and Heating Systems

The existing digested sludge transfer pump room is an unclassified space under NFPA820. There is an air supply duct in this room which provides air for ventilation purposes. However, there is no air return duct, which results in poor pump room ventilation. There is an existing hydronic heating wall fin convector in the pump room which provides supplementary heat for this area. There is no localized temperature control or interface with heating systems in this room. The existing parts storage room, adjacent to the pump room, will house new electrical and variable frequency drive (VFD) equipment. This room has a supply air duct and hydronic wall fin convector for ventilation and heating purposes.



8.6.1.2 Upgrades to Ventilation and Heating Systems

8.6.1.2.1 Existing Pump Room

Based on heat dissipation from the new pumps, separate air ventilation and heating systems will be provided. Ventilation system will consist of one (1) supply and one (1) exhaust fan. Hydronic unit heaters will be used for heating purposes. To avoid any conflict between the existing heating and ventilation system and the new systems, the existing air supply duct and wall fin convector will be demolished and hot water pipes to be capped. New supply and exhaust fans are will be equipped with VFD to give more flexibility in air change rate for summer and winter conditions. The air change rate for summer time is based on heat dissipation from pump motor.

8.6.1.2.2 Electrical and VFD Room

One (1) indoor AC unit with remote condenser (i.e., DX split unit) will provide cooling. The AC unit capacity depends on the heat dissipation from electrical panels and VFDs, which is to be confirmed. The existing air supply duct will be retained for fresh air and positive pressurization purposes.

8.6.1.3 HVAC Controls

Air conditioning unit in the electrical room will have stand alone control to operate the system based on the temperature setting. Supply and exhaust fans in the Digested Sludge Transfer Pump Station will have local control panel with VFDs to change fan speed and room air change rate based on the space temperature. Unit heaters are proposed to operate through wall mounted thermostat. Room temperature sensors will be capable to send a general alarm signal to SCADA in the event of high temperature in this room.

8.6.2 Plumbing and Drainage

8.6.2.1 Potable Water

No changes will be made to the existing system.

8.6.2.2 Plant Service Water


8.6.2.3 Roof Drain System


8.6.2.4 Floor Drain System


8.6.2.5 Sanitary Sumps


8.6.3 Emergency Safety Equipment

As required by OBC and OFC fire protection system i.e. standpipe system and fire extinguishers will be provided throughout, as applicable.



8.7 Electrical Design

The electrical design of the digested sludge transfer pumping system is presented in detail in Section 17.

8.8 Instrumentation and Control Design

Instrumentation and control design is presented in Section 18.6.

8.9 Construction Sequencing, Tie-Ins, and Demolition

Construction sequencing, tie-ins and demolition details are presented in Section 19.



9. Anaerobic Digestion (Contract 2b) 9.1 Existing Anaerobic Digestion System

Two (2) existing primary digesters (formerly Digesters No. 5 and 6) are currently being operated at the Kitchener WWTP; both digesters have gas mixing systems and are heated. The heat exchangers and gas compressors are located in an enclosure on top of the digesters. Mixing guns are located at the mid-circumference of the digesters. Hot water supply is provided by three (3) boilers located in the existing heating plant and administration building, and two (2) hot water pumps located at the mezzanine level of the primary digester control building. Two (2) existing secondary digesters (Digesters No. 3 and 4) are currently operated as holding tanks. Digester No.3 is equipped with a floating cover that allows for variable volume operation and some gas storage. Digester No. 4 is used as a storage tank and is not connected to the digester gas system. Digested sludge from the primary digesters is gravity fed to existing Digesters No. 3 and 4. A sludge transfer pump is located in the basement of the primary digester control building and was originally dedicated to transferring sludge from the primary digesters to the secondary digesters but is no longer in operation. Two (2) existing digesters (Digesters No. 1 and 2) were abandoned during previous plant updates. These existing abandoned digesters will be removed under this project and Digesters No. 5 and No. 6 will be renamed Digesters No. 1 and No. 2. Digester gas collected from both primary and secondary digester is sent to the boilers. Gas boosters are used to increase the digester gas pressure to the boilers. Excess gas is sent to two (2) open-type waste gas flares. The existing hot water boiler system, built in 1998, includes three (3) boilers and three (3) digester gas boosters. The boiler system is in disrepair and does not meet current TSSA standards. This digestion upgrade project is being undertaken to address mechanical deficiencies, allow operation of existing Digester No. 3 for both sludge and digester gas storage, upgrade the gas system to meet current gas safety standards, and replace the existing hot water boilers. The upgrades are based on new boilers and digester gas boosters. Key upgrade components include: A new digester control building to extend the existing primary digester building to connect with the two (2)

existing primary digesters (Digesters No. 1 and 2) and the secondary digester (Digester No. 3). The new digester control building will include: Ground floor to hold heat exchanger, MCC, janitor, gas, air blower, boiler and gas booster rooms Basement to hold primary digester pump room, drip trap room, and secondary digester pump room Walkways on both ground and basement levels Two (2) enclosed stairs to access the pump rooms and walkway at the basement level One (1) open stair in the gas room to access the drip trap room at the basement level MCC room and janitor rooms in their original location to maintain existing electrical wiring and plumbing Existing ground level bulkheads; access to the two (2) primary digesters will be abandoned and new

bulkheads will be provided to accommodate the digester control building Two (2) new fixed steel covers for the two (2) primary digesters. New mixing systems for the two (2) primary digesters, each consisting of an arrangement of floor mounted and

surface nozzles fed by the digester sludge mixing pumps; three (3) digester sludge mixing pumps (2 duty, 1 common standby) located at the new primary digester pump room for easy accessibility for O&M.



A mixing system for the secondary digester will be added, consisting of an arrangement of floor mounted nozzles fed by the digester sludge mixing pumps; two (2) mixing pumps (1 duty, 1 standby) will be located in the new secondary digester pump room.

One (1) new membrane gas holder system to replace the existing floating cover of Digester No. 3. The membrane gas holder system consists of a membrane cover, an air system with two (2) air blowers, air purge system, and gas safety equipment.

Two (2) new heat exchangers (2 duty), each rated at 5.3 GJ/h will be installed in the primary digester control building to heat the recirculated sludge in both primary digesters.

Three (3) new sludge recirculation pumps (2 duty, 1 common standby) will be installed in the new primary digester pump room to circulate sludge through the heat exchangers.

Three (3) new gas boosters will be installed in the new gas booster room and three (3) new boilers will be installed in the new boiler room to supply hot water for primary digester heating and the new digester control building space heating.

Two (2) new hot water recirculation pumps (1 duty, 1 standby) will be installed in the new boiler room, to supply hot water in the recirculation system to the sludge heat exchangers and the space heating system.

Two (2) new sludge transfer pumps will be installed at the basement of the existing primary digester control building to transport sludge between two (2) primary digesters and from the primary digesters to the secondary digester (Digester No. 3). The transfer pump would not normally be in operation, but would be used if the normal gravity transfer is unavailable due to thick sludge or clogged overflow lines. The new sludge transfer pumps will be able to remove most of the primary digester contents by transferring sludge to the secondary digester (Digester No. 3) when the primary digester is taken off line due to maintenance.

A new digester gas handling system, including new gas piping for primary and secondary digesters, two (2) new waste gas burners, drip traps, sediment traps, flame arresters, vacuum/pressure relief, and back pressure regulators, will be installed to handle digester gas.

The hot water circulation system and digester gas header will have connections for future CHP. Existing Secondary Digester No. 4 will be abandoned. Existing former Digesters No. 1 and 2 will be demolished.

The digestion upgrade design will follow MOE design guidelines, NFPA 820, and the latest Code for Digester Gas and Landfill Gas Installation (CSA Standard B149.6-11).


A simplified process flow schematic for the liquid and gas trains of the anaerobic digestion system are presented in Figure 11 and Figure 12, respectively.



Figure 11 Simplified Process Flow Schematic of the Liquid Train of the Anaerobic Digestion System



Figure 12 Simplified Process Flow Schematic of the Gas Train of the Anaerobic Digestion System

Anaerobic digestion upgrades drawings (Series 300) are contained in Appendix A. The preliminary process control narratives and process and mechanical equipment lists are presented in Appendix J and K, respectively.

9.3 Process Design

9.3.1 Anaerobic Digesters


The existing Primary Digesters No.1 and No. 2 and Secondary Digester No.3 will be upgraded to provide sludge stabilization prior to dewatering and final disposal. Primary sludge from the primary clarifiers will continue to be pumped into a common pipeline that feeds sludge to the primary digesters. A second sludge supply line will convey thickened waste activated sludge (TWAS) to the primary digesters. In the future, this second sludge supply line will convey TWAS and thickened primary sludge to the primary digesters. Each primary digester will have two (2) sludge feed lines connecting to the primary sludge and TWAS supply lines, respectively, and each sludge feed line will have a motorized isolation valve to control sludge feed and a flow meter to measure sludge fed to each digester. The addition points of both primary sludge and TWAS discharge to the primary digesters are on the sludge circulation lines downstream of the heat exchangers. Sludge feed will alternate between the two (2) primary digesters to maintain even distribution of sludge, and this alternative operation will be controlled through SCADA either at a preset time interval or at a preset totalized primary sludge and TWAS flow as measured by the two (2) flow meters on the two (2) sludge feed lines to each primary digester.



9.3.1.2 Design Criteria

Table 40 presents design criteria related to the digestion upgrades being carried out as part of the Phase 3 Kitchener WWTP upgrades. Table 40 Anaerobic Digester Design Criteria

Parameter Value

Primary Digester Volume - Each - Total

Secondary Digester Volume

7,806 m3

15,612 m3 7,011 m3

Primary Sludge Thickened Waste Activated Sludge Total Sludge to Anaerobic Digestion Solids Loading

- Average - Peak

18,698 kg/d 26,232 kg/d

20,890 kg/d 29,315 kg/d

39,588 kg/d 55,547 kg/d

Flow - Average - Peak

591 m3/d 830 m3/d

402 m3/d 564 m3/d

993 m3/d

1,393 m3/d Solids Concentration 3.1% 5% 3 - 5 % Hydraulic retention time

- Average - Peak

15.72 days 11.20 days

9.3.1.3 Preliminary Design Specifications

Table 41 provides preliminary design specifications for the upgrades to the existing anaerobic digesters at the Kitchener WWTP. Table 41 Preliminary Design Specifications for Anaerobic Digesters

Item Specification

Primary Digester Cover Type Fixed, radial beam steel, rooftop foam insulation and protective membrane No. of Units 2 Size, each 30.5 m dia.

Membrane Gas Holder No. of Units 1 Storage Capacity 6,244 m3 (4 kPa gauge at 35ºC) No. of Air Blowers 2 (1 duty and 1 standby) Air Blower Motor Size 3.7 kW (5 hp)

9.3.1.4 Operating Philosophy, Instrumentation and Controls

The two (2) primary digesters are operated in parallel. Primary sludge and TWAS will be directed to the two (2) primary digesters. Digested sludge will overflow by gravity to the secondary digester for storage. Digested sludge will be pumped from the secondary digester to the WWRMC using pumps located in the existing maintenance building, and the pump suction is through an independent sludge withdrawal line passing the basement of the exiting secondary digester control building. In the future, new digested sludge transfer pumps will be installed in the new secondary digester pump room, and the future pump suction will connect with the secondary digester mixing pump suction. A significant change in operating philosophy of the upgraded digestion system is that the secondary digester will have variable gas storage capacity, made available by the new membrane gasholder cover. Digester gas generated in the digestion process can accumulate under the new membrane cover.



9.3.2 Digester Mixing


One of the most important aspects for optimal performance and operation of high-rate primary digesters is proper mixing. Although gas bubbles generated by the anaerobic digestion process and thermal convection currents caused by the addition of heat generate mixing currents within the digester, these currents are not adequate to ensure stable digester performance at high loading rates. It is necessary that a mixing system be installed to create a homogeneous environment within the reactor so that the digester volume can be fully utilized. Mixing minimizes process-gradients (e.g., variations in temperature and solids concentration) and ensures that the heavy solids are entrained to minimize scum and grit accumulation. The secondary digester will be mixed to ensure consistent solids, but will not be heated. Hydraulic mixing is a relatively new technology compared to mechanical and gas mixing. Hydraulic mixing utilizes a chopper pump that draws liquid from the tank, and discharges it through a series of strategically mounted jet nozzles in the tank. A chopper style pump ensures that ragging and roping problems, which are common in digester operations, are minimized.


Table 42 presents design criteria related to the digester mixing upgrades. Table 42 Design Criteria for Digester Mixing

Parameter Value

Primary Digester Volume

Each 7,806 m3

Total 15,612 m3

Secondary Digester Volume 7,011 m3

Mixing Intensity Based on Manufacturer’s CFD analysis


Table 43 provides design specifications for the upgrades to the existing anaerobic digester mixing system. Table 43 Preliminary Design Specifications for Digester Mixing

Item Specification

Primary Digester Mixing System

No. of Units 3 (2 duty, 1 common standby) Capacity, each 505 L/s Motor size Min. 93 kW (125 hp) Mixing Nozzle Arrangement 2 sets, each has 2 single floor mounted, 5 double floor-mounted, and 2 single wall-

mounted (scum) nozzles Secondary Digester Mixing System

Type Hydraulic No. of Units 2 (1 duty, 1 standby) Capacity, each Min. 388 L/s Motor size Min. 56 kW (75hp) Mixing Nozzle Arrangement 1 set with 2 single floor mounted, and 4 double floor-mounted nozzles

The use of mixing pumps with VFDs, which may minimize foam development in the digesters, will be considered during the detailed design phase.




Each primary digester will be equipped with a new hydraulic mixing system to maintain sludge temperature and consistency, which will aid in digestion performance. Flexibility will be provided in SCADA to adjust pump operating cycles to minimize energy consumption, while maintaining a consistent sludge blend.

9.3.3 Digester Heating and Recirculation


The temperature in each primary digester will be maintained at 35ºC using a dedicated sludge recirculation pump and heat exchanger. A hot water circulation pump and a three-way temperature regulating valve will regulate heat input to the heat exchangers to maintain the design temperature in the digesters.


Table 44 presents design criteria related to the digester heating and recirculation upgrades being carried out as part of this upgrade project. Table 44 Design Criteria for Digester Heating and Recirculation

Parameter Value

Peak Month Flow to Primary Digesters 1,393 m3/d

Primary Digester Design Temperature 35°C

Minimum Raw Sludge Temperature 10°C

Minimum Outdoor Temperature -30°C


Table 45 provides design specifications for the upgrades to the digester heating and recirculation at the Kitchener WWTP. The boiler hot water system also provides space heating for the new digester control building. Table 45 Preliminary Design Specifications for Digester Heating and Recirculation

Item Specification

Primary Digester Sludge Recirculation Pump No. of units 3 (2 duty, 1 common standby)

Capacity, each 28 L/s at 36 m TDH Motor size 26 kW (35 hp)

Heat Exchanger No. of units 2 (both duty)

Capacity, each 5.3 GJ/h

Boiler No. of Units 3 (2 duty, 1 standby)

Rated Output Capacity, each 5.3 GJ/h

Hot Water Recirculation Pumps (in new boiler room) No. of Units 2 (1 duty, 1 standby)

Capacity, each 63 L/s at 30 m TDH Motor Size 29.8 kW (40 hp)


The upgraded digester heating and recirculation system will heat the two (2) primary digesters to maintain sludge temperature, which will ensure adequate digestion. Flexibility will be provided in SCADA to adjust pump operating cycles to minimize energy consumption, while maintaining a consistent temperature.



9.3.4 Digester Gas Handling System


The digester gas system collects digester gas produced in the anaerobic digestion process and manages the gas for combustion. Digester gas will be stored in the secondary digester membrane cover and burned as a source of fuel for the CHP and as required in the hot water boilers. Excess digester gas production is flared in the waste gas burners. Wasting to the waste gas burner will be automatic through a mechanical system including a pressure relief valve that controls the maximum gas pressure in the digesters.


Table 46 presents design criteria related to the digester gas handling system upgrades. Table 46 Design Criteria for Digester Gas Handling System

Parameter Value

Average Gas Production 13,701 m3/d

12,787 MJ/h

Peak Month Gas Production 19,224 m3/d

17,942 MJ/h


Table 47 provides design specifications for the upgrades to the digester gas handling system. Table 47 Preliminary Design Specifications for Digester Gas Handling System

Item Specification

Waste Gas Burner Type Enclosed flame

No. of Units 2 (1 duty, 1 standby)

Capacity, each 20,000 m3/d

Digester Gas Booster No. of Units 3 (2 duty, 1 standby)

Capacity, each 300 m3/h

Motor Size 3.7 kW (5 hp)


The CHP has been planned for the near future to convert digester gas into heat and power. Before the CHP is operational, excess or stored gas will normally be utilized by the new boilers, which will be supplied digester gas by three (3) hermetically-sealed gas boosters (2 duty, 1 standby). Excess digester gas beyond the boiler requirements will be flared through two (2) new waste gas burners (1 duty, 1 standby). Each boiler will require 300 m3/h of digester gas. The boilers will produce hot water to heat the primary digesters, as well as provide building space heating when required. The boilers will utilize digester gas as a primary fuel and natural gas when insufficient digester gas is available. After the CHP is operational, excess or stored gas will be normally utilized by the co-generation equipment for power generation, and waste heat from the CHP will be recycled and sent to the sludge heat exchangers to heat the primary digesters as well as provide building space heating when required. The boilers will normally be on standby and produce hot water using digester gas for primary digester heating only when the CHP is offline for maintenance/repair or when the heat demand exceeds the capacity available from the CHP. During cold days, when



waste heat from the CHP is insufficient to heat the primary digesters, the boilers will utilize digester gas or natural gas to produce supplementary heat.


The new digester control building will extend the existing primary digester control building from the front and connect it to the existing primary digesters (No. 5 and 6) and the existing secondary digester (No.3) from the exterior. Expansion joints will separate the new digester control building from the existing digesters and control building. The digester control building basement will house pump rooms and a drip trap room to meet process requirements. The basement will be accessed by stairwells. All basement exterior walls, stairwell walls, base slabs, floor slabs, columns and beams will use cast in place concrete. The stair flights will use pre-cast units in order to eliminate the formworks and speed up the construction progress. Some modifications to the existing digesters and control building will be required, including the relocation of the accesses to the primary digesters and partial demolitions to the existing control building. These modifications will need structural treatment and will not affect the integrity of the existing structures. The roofline may have to be adjusted to accommodate the membrane gas storage system to be installed on the secondary digester. The new boiler room is on the ground floor of the new digester control building and will not require a basement. The boiler room will be separated from the other part of the digester control building structure by expansion joints, and the foundation will strip footing to the depth below the local frost level. The floor slab will be supported on the foundation walls. Compacted granular backfill underneath the floor slab is required due to the equipment and operating requirement. The appearance of super-structures for the digester control building will match the surrounding structures. The roof structures will be determined by the exterior wall system of the super-structures, and will be either cast in place column with pre-cast units or load bearing wall system with the pre-cast units. The pre-cast units plus concrete topping will form the roof diaphragm to transfer the lateral load. The usage of the pre-cast units will avoid the shoring and formworks for the suspended roof slab, allowing the contractor to speed up the entire construction activity and shorten the entire construction time. The supporting structure for the waste gas burners is an independent and elevated concrete structure consisting of cast in placed concrete walls, slabs, and footings. The surface mounted ladders to the walls and guardrails around the entire and structures top slab will be required to create the safe working space.



Indoor design conditions are summarized in Table 48.



Table 48 Indoor Design Criteria Applicable to the Anaerobic Digestion System Areas Criteria

Heat Exchanger Room 5.5 °C above outdoor temperature (summer), 10 °C (winter)

MCC Room 27 °C (summer), 18 °C (winter)

Boiler Room 5.5 °C above outdoor temperature (summer), 18 °C (winter)

Gas Booster Room 5.5 °C above outdoor temperature (summer), 10 °C (winter)

Gas Room 5.5 °C above outdoor temperature (summer), 10 °C (winter)

Air Blower Room 5.5 °C above outdoor temperature (summer), 10 °C (winter)

Primary Digester Pump Room 5.5 °C above outdoor temperature (summer), 10 °C (winter)

Secondary Digester Pump Room 5.5 °C above outdoor temperature (summer), 10 °C (winter)

Drip Trap Room 5.5 °C above outdoor temperature (summer), 10 °C (winter)

9.5.1.1 Heating System

Because ventilation rates are mandated by NFPA 820, a significant heating load is anticipated for the new facility. A preliminary ventilation and space heating load analysis shows that the maximum heating load for building will be approximately 800,000 Btu/h range. Three (3) new gas fired hot water boilers with pumps, heat exchangers and glycol components will provide heating for process heat exchangers, building and air handling units (AHUs). The loop for AHUs will incorporate variable speed pumps on a duty/standby basis to match the flow to the heating water demand, glycol recirculation loops will be utilized with intermediate plate and frame glycol hot water heat exchangers to ensure the heating coils do not freeze. Horizontal or vertical discharge glycol hot water unit heaters, duct heaters or glycol hot water convection heaters will be placed for stairs, mechanical rooms and rooms with overhead doors. Electrical unit heaters will be used, to avoid hydronic systems, within electrical rooms. For boilers, natural gas and digester gas is available and will be used as a heating source.

9.5.1.2 Ventilation Systems

The ventilation rates for the anaerobic digestion areas are summarized in Table 49.



Table 49 Ventilation Rates for the Anaerobic Digestion Systems Location and

Function NFPA 820

Table and Row NFPA

Classification NFPA Ventilation Rate Ventilation Rate and Additional Notes

Heat Exchanger Room N/A Unclassified N/A Ventilation rate is based on heat relief and occupancy

- Continuously ventilated up to 6 ACH (Occupied)

MCC Room N/A Unclassified N/A Ventilation rate is based on heat relief and AC recommended

Boiler Room N/A Unclassified N/A Ventilation rate is based on heat relief

Gas Booster Room Table 6.2 Row 18 Line A Class I Div. 1 Continuously ventilated at

12 ACH 12 air changes per hour

Gas Room Table 6.2 Row 18 Line A Class I Div. 1 Continuously ventilated at


Air Blower Room N/A Unclassified N/A Ventilation rate is based on heat relief and occupancy - Continuously ventilated up to 6 ACH (Occupied)

Primary Digester Pump Room N/A Unclassified N/A Ventilation rate is based on heat relief and occupancy


Secondary Digester Pump Room N/A Unclassified N/A Ventilation rate is based on heat relief and occupancy


Drip Trap Room Table 6.2 Row 18 Line A Class I Div. 1 Continuously ventilated at


9.5.1.3 Air Conditioning

A ceiling mounted AC unit will be installed in the MCC Room to prevent electrical equipment from overheating.



Potable water will be supplied to the building for sanitary uses. Low water use plumbing fixtures and trim will be specified, and cross-connection control will be provided, in accordance with requirements of the OBC. Potable water will be metered at the building.


Plant service water will be supplied to the building for treatment process uses. Service water will be provided with a self-cleaning strainer where the service water enters the building.


Roof drains are provided and discharge to the treatment plant storm drain system.


Two (2) floor drain sumps, each equipped with duplex submersible pumps, are provided in the Primary Digester Pump Room and Secondary Digester Pump Room, respectively. Drainage from these sumps will be pumped to the nearest sanitary sewer or to the nearest sewage channel.


An emergency eye/face wash station and associated water heater will be provided in the southeast corner of the boiler room.


The electrical design of the anaerobic digestion system is presented in detail in Section 17.






All work will be sequenced to ensure that one (1) primary digester remains available at all times. For short-duration shut-downs (i.e., 4 hours), primary sludge feed to the digesters will be suspended, at which time sludge will be “stored” in the primary clarifiers. Existing Primary Digester No. 5 is currently offline, so digester modification will start with existing Primary Digester No. 6. The upgrades will take the sequence of work into consideration. To permit staging of construction prior to heat being available from the CHP, and to permit demolition of the existing boiler building (i.e., the old administration building that contains the existing boilers), these existing boilers and ancillary equipment will be relocated to a temporary building. When the new digester control building is complete, the new boilers will be installed, and will be used as backup to the CHP heating, and to augment heating when there is a shortfall from the CHP. Construction sequencing, tie-ins and demolition details are presented in Section 19.



10. Headworks (Contract 3a) 10.1 Existing Headworks Facility

The existing headworks facility was constructed in 1977, along with the elevated influent channels, as a part of the second expansion to the Kitchener WWTP. The influent channel is an elevated channel that feeds the Headworks Building and includes bulkhead provisions to allow for future extensions. Prior to entering the Headworks Building, wastewater passes through an energy dissipation chamber and a split flow chamber. The existing influent channel is equipped with a Parshall flume flow meter that measures the incoming wastewater flow rate. The headworks facility is an enclosed two-storey concrete building located east of the primary clarifiers. The building includes a screen room, screening/grit bin room, chemical pumps area, and a storage building located under the outdoor detritors (used for grit removal). Flow entering the headworks is split into three (3) screen channels, where bar screens are installed to provide preliminary treatment. The bar screens (with rake mechanisms) are located on the top floor of the Headworks Building, and discharge into a reversible belt conveyor (600 mm wide) used to transport screenings to a chute at the end of the conveyor. The chutes discharge into two (2) bins in the bin rooms at the ground level. Screened wastewater is directed through sluice gates (1.2 m x 1.2 m) to the detritor tanks (10.7 m x 10.7 m) for grit removal. The detritors are equipped with a revolving scraper arm and grit conveying mechanism. The grit is discharged through chutes to the screenings collection bins. As concluded in the Site Wide Facility Plan and the Preliminary Design Basis Summary, a new Headworks Building will be constructed as part of the Phase 3 Kitchener WWTP Upgrades.


The Kitchener WWTP is being upgraded to provide treatment capacity for the projected flow in year 2041. The Headworks Building has been designed to provide treatment capacity for an average flow of 123 MLD and hydraulic capacity to accommodate a peak instantaneous flow of 430 MLD. In addition, the Headworks Building has been designed such that flow capacity can be increased to an average capacity of 140 MLD in the future without significant building modifications. The following key features have been incorporated into the preliminary design of the Headworks Building in order to protect subsequent process equipment and provide effective and reliable preliminary treatment performance: Two (2) new Parshall flume flow meters Four (4) new perforated 6 mm screens Two (2) new sluicing channels and washer compactors for screenings handling Two (2) new vortex grit separators, grit pumps, and classifiers for grit removal and protection of downstream

equipment Phosphorus removal chemical system Channel aeration Addition of a second influent channel to eliminate hydraulic bottleneck and accommodate peak instantaneous

plant flow Emergency overflow channel to prevent flooding under emergency high flow conditions Odour control NFPA 820 compliance

A simplified process flow schematic of the headworks system is presented in Figure 13.



Figure 13 Simplified Process Flow Schematic of the Headworks System

The new Headworks Building will be constructed adjacent to the existing Headworks Building to minimize the required new channel construction. The two-storey building will house all screening and grit removal equipment, a dedicated electrical room, a bin room, a boiler room and spare floor space for equipment such as compressors and channel aeration blower. The bin room will be accessible from the main plant access road through two (2) large roll-up doors. A chemical containment area with four (4) storage tanks and a chemical pump room will be constructed adjacent to the new Headworks Building. A modular biological treatment unit consisting of a bioscrubber and biofilter located adjacent to the new Headworks Building, will be installed for headworks odour control. The preliminary footprint of the new building is approximately 25 m x 35 m. Process equipment such as screens, washer compactors, and classifiers will be located on the second floor of the building, while the grit pumps and disposal bins are located on the ground floor. The vortex grit separators will be constructed outside of the Headworks Building. The electrical room will be located on the second floor, while HVAC units will be located on the roof of the building. Due to the high flood water level at the site, all entrances to the building, including access to the first floor (except the bin room which must be at grade for truck access) will be situated above the regional flood elevation of 283.63 m. Included within the same contract as the headworks facility is the construction of a new 12 m x 6 m pilot plant facility. This facility will include laboratory facilities to be used primarily by researchers and students from the University of Waterloo to conduct experiments, studies, testing, research and lab work related to wastewater treatment.



Headworks drawings (Series 400) are contained in Appendix A. The preliminary process control narratives and process and mechanical equipment lists are presented in Appendix J and K, respectively.

10.3 Process Design

10.3.1 Raw Sewage Flow Monitoring


Two (2) Parshall flume flow meters will be installed on the new influent twin channels immediately upstream of the new Headworks Building. The use of Parshall flume flow meters are recommended because it is an economical option that requires little maintenance and is able to provide reliable flow monitoring. In addition, the technology is favoured as the operation staff are familiar with the existing Parshall flume flow meter.


The Parshall flume flow meters design is based on accommodating a peak flow of 430 MLD.


The Preliminary Design of the Parshall flume flow meters is based on two (2) flow meters with a throat width of 1.8 m installed in two (2) 2.5 m wide channels.


The flow meters will be connected to the Plant SCADA system and provide flow measurement data for process control purposes.

10.3.2 Screening


The new headworks facility will be connected to the existing plant influent channel by a new section of twin influent channels. Given the high elevation of the influent channel, the screening channels and all screening handling equipment will be located on the second floor of the Headworks Building. An auto-sampler will be installed downstream of the screen channels to provide raw wastewater samples for analysis. Raw wastewater enters the headworks by gravity through a flow split inlet structure and is guided to the screening channels. The new headworks facilities will house five (5) channels – four (4) fine screen channels, each equipped with a perforated plate fine screen with 6mm opening size and one (1) emergency overflow channel. All channels will be equipped with inlet and outlet motorized sluice gates for channel isolation. Each fine screen will be sized for 143,300 m3/d (143.3 MLD), such that three (3) duty screens are sufficient to provide the peak instantaneous flow capacity 430,000 m3/d (430 MLD). The emergency overflow channel, which will have the same width and depth as a fine screen channel, is designed to provide emergency overflow capability in extreme high flow events and emergency conditions. Two (2) ultrasonic level transmitters will be mounted in the common inlet channel upstream of the screens and two (2) ultrasonic level transmitters will be mounted in the common outlet channel downstream of the screens. The level transmitters will monitor the level differential across the screens and send the signal to SCADA for screen control. Solid screenings collected from the fine screens will drop into two (2) sluicing channels and conveyed to two (2) washer compactors using de-gritted wastewater. Interconnection piping and valves will be installed on the sluicing



channels so that screenings can be diverted to either washer compactor. A level transmitter and an overflow pipe will be installed in each sluicing channel for level control. Normally, the washer compactors will operate simultaneously. However, each washer compactor has been sized with 100% screenings handling capacity for the peak instantaneous flow of 430,000 m3/d, such that the two (2) washer compactors can be operated in a duty/standby arrangement if required. The drainage flow generated from the washer compactors will be returned by gravity to the screen channel (downstream of the screens). The new Headworks Building will house two (2) conveyors in the bin room, directly above the disposal bins. Since the height at the facility allows all washer compactors and classifiers to discharge solids to the ground floor without incline conveyors, each distribution conveyor is designed to collect solids from a washer compactor and a classifier before distribution to the disposal bin. Hydraulic calculations and consultation with screen suppliers have confirmed that screens with the width between 1.8 m and 2.4 m are suitable. However, considering the larger channels/screens offer flexibility for future expansion at a relatively small capital cost, 2.4 m wide screens and 2.5 m screen channels were selected.


Table 50 summarizes the design criteria of the screening and screenings handling system used in the development of the Preliminary Design. Table 50 Design Criteria for Screens and Screenings Handling

Parameter Criteria

Average (123 MLD) Hydraulic Peak (430 MLD)

Number of Screens (Duty/Standby) 4 (3 duty, 1 standby) Design flow rate per screen 61,400 m3/d 143,300 m3/d

Number of Duty Screens 2 3

Fine Screens Type Perforated plate with 6 mm circular openings Approach Velocity < 0.6 m/s

Headloss, with 30% screen area blocked < 0.4 m < 0.4 m

Upstream Water Level (based on hydraulic profile) 0.8 m 1.4 m

Estimated Screenings Quantity1 55 L/1000 m3 148 L/1000m3

Average Daily Screenings Production 2.2 m3/d Note: 1. Based on WEF MOP 8, Page 11-6, 2010 - estimated quantities for fine (6mm) screening.


Table 51 summarizes the preliminary design specifications for the screening process.



Table 51 Preliminary Design Specification for Screens and Screenings Handling Item Specification

Fine Screens

No. of units 4

Peak flow rate per unit 145,000 m3/d

Screen type Perforated plate with 6 mm circular openings Motor size

Screen drive Brush drive

3.7 kW 2.2 kW

Channel Specifications Channel width 2.5 m

Channel depth 2.5 m

Sluicing Channel2

Channel length 40 m

Conveying capacity 30 m3/h

No. of units 2

Screenings Washing Compactors

Minimum compaction 60%

Processing capacity 4.3 m3/h (screened solids)

No. of units 2 Motor size

Grinder Compactor

7.5 kW 2.2 kW

Disposal Bins1 Volume, each approx 15 m3

No. of units 2 Note: 1. Disposal bins have been assumed as being used for screenings combined with grit. Ability to separate screenings from grit to be made. Flexibility to

combine screenings and grit into a bin or screenings to one bin and grit to the second bin to be provided. 2. De-gritted wastewater will be used in sluicing


10.3.2.4.1 Screen Start-Up

The screening equipment will be designed to operate automatically. Under average flow conditions, two (2) duty screens will be operational, one (1) duty screen will be in idle mode, and one (1) screen will be in standby mode. The idle duty screen will have inlet and outlet gates closed and will start automatically when the differential liquid level rises beyond the high level differential setpoint. The three (3) duty screens will be programmed to rotate between operational and idle modes every two (2) days (adjustable), in order to minimize odours in the idle duty screen channel. When a screen is in standby mode, the respective channel will be isolated and drained using a portable submersible pump.

10.3.2.4.2 Stepping Sequence

Under normal operating conditions, the fine screen plate will rotate upwards (step) towards the brush drive by one (1) plate at a preset stepping frequency (e.g., 10 min). If a “high level” differential setpoint is reached, the timer control will be overridden, and the screen will move upward before the time interval is reached. If the differential level continues to rise when all three (3) duty screens are in service, the screens will increase the stepping frequency until they reach the highest speed. After a predetermined number of steps, the screens automatically initiate a cleaning sequence.

10.3.2.4.3 Cleaning Sequence

Each screen will be fitted with a spray water solenoid valve, which is activated whenever the screen initiates a cleaning cycle. A cleaning cycle, which backwashes the screen sections, is started after an operator configurable time period or after a set number of stepping cycles (e.g., 5), whichever happens first. The brush also runs in reverse for a pre-determined time during the cleaning cycle, to optimize cleaning. During operation in high differential level conditions, wash water spray through the solenoid valve is continuously provided.



Under high-high differential level conditions, the standby screen will be commanded to start automatically (if available) and the screens enter a “high speed” cleaning cycle. During the high speed cleaning cycle, the screens will move continuously, with spray water and brush drive operating simultaneously. This cycle will continue until the “Normal” differential water level is reached, with a preset delay. Cleaning sequences vary by screen manufacturer.

10.3.2.4.4 Emergency Overflow Sequence

An emergency overflow sequence will be initiated when the following conditions are met: All available screens (duty and standby) are in operation with “high speed” cleaning cycle A pre-determined critical high level is reached Extreme high flow condition

Under this high flow situation, signalled by both high water level and high flow measurement, the inlet and outlet gates of the emergency overflow channel will be opened automatically to alleviate the flow. The high level alarm would result in a latched circuit that would keep the inlet and outlet gate open until an operator manually resets the latch at a control panel.

10.3.3 Grit Removal


The new Headworks Building will house a grit removal system that will replace the existing detritor system. The grit removal system consists of two (2) vortex grit separators, equipped with three (3) grit pumps and two (2) grit classifiers. The two (2) vortex grit separators are designed to effectively remove small particles from a peak design flow of 307,000 m3/d, and also designed to hydraulically accommodate the peak instantaneous flow of 430,000 m3/d. The grit removal system was designed to allow for a grit removal efficiencies of:

95% for grit larger than 300 micron diameter 85% for grit larger than 200 micron diameter 65% for grit larger than 150 micron diameter

Screened effluent will be directed to two (2) vortex grit separators through the respective sluice inlet gates. Each vortex grit separator can be isolated by closing the corresponding inlet/outlet gates. The two (2) vortex grit separators induce grit separation from the screened effluent by inducing a vortex pattern in the circular chamber, where the denser grit will settle by centrifugal force and gravity. The centrifugal force is generated by a mechanical agitator in continuous slow rotation, which maintains the circulation in each vortex unit under all flow conditions. Grit accumulated in the vortex hopper will be periodically pumped to a dedicated grit classifier. Grit bed fluidization will be provided by opening the solenoid valve for scouring using de-gritted wastewater. The drainage flow generated by the grit classifiers will be discharged to the screen effluent channel by gravity. The grit slurry produced by the grit classifiers will be settled, dewatered, and dropped into a screenings/grit conveyor on the first floor and eventually into a disposal bin.


Table 52 summarizes the design criteria for the grit removal system used as a basis for the Preliminary Design.



Table 52 Design Criteria for Grit Removal System Parameter Criteria

Hydraulic Design

Average design flow 122,745 m3/d

Peak design flow 306,862 m3/d

Hydraulic capacity 430,000 m3/d

Grit Tanks Vortex type

No. of units 2

Capacity (at Peak Design) 154,000 m3/d per tank

Solids Handling Design

Average grit production rate1 37 L/1,000m3 grit slurry

Peak grit production rate1 148 L/1,000m3 grit slurry

Average daily grit production 1 m3/d Note: 1. Average and peak grit production rate based on WEF MOP 8, Page 11-51, 2010


Table 53 presents the grit removal preliminary design specifications. Table 53 Preliminary Design Specifications for Grit Removal

Item Specification

Grit Tanks Diameter 6 m

Depth 6.5 m

Internal headloss 6 mm

Grit Pumps

Type Dry Pit Recessed Impeller Pump

No. of pumps 3 total (2 duty 1 common standby)

Pump capacity 15 L/s @ 10 m TDH

Motor size 7.5 kW

Conveyors No. of units 2

Motor size 1.1 kW

Grit Classifiers

No. of units 2

Motor size 2.2 kW


Under normal operating conditions, both vortex grit separators will operate simultaneously. The vortex agitators are designed to run continuously to maintain vortex motion within the grit chamber. In the event of a vortex unit failure, the failed vortex unit will be isolated and taken offline by closing the associated isolation gates. Three (3) grit pumps, one (1) dedicated to each vortex unit and one (1) common standby, will be provided to transfer grit from the vortex units to the grit classifiers. In the event of a grit pump failure, the shared standby pump can be called into service. To utilize the standby pump, corresponding valves on the pump discharge interconnection piping must be closed/opened so that flow can be diverted. Grit pumping will be designed to operate in cycles based on a preset time interval (initial setting at 10 minutes every hour). The grit pumping cycle will consist of the following sequence: 1. The water scour solenoid valve will open to fluidize grit accumulated in the vortex unit



2. After a set water scour period has elapsed for a given vortex unit, the grit flushing water valve will open and the associated grit removal pump will start. The grit slurry pump will continue to operate for pre-set period of time. After the set time period has elapsed, the grit pump will stop, and the discharge and flushing water valves will close

3. When the grit pumping cycle is completed, the associated scour water solenoid valve will close 4. When the grit pump stops, the associated discharge motorized valve will close to prevent backflow from the grit

classifiers Seal water, controlled by solenoid valves, will be provided for the grit pumps. The solenoid valves will be hardwire interlocked to the corresponding pump circuit, to open and provide seal water each time the pump is called to start. Control of the seal water station will be provided by a LCP, and only alarms will be reported to SCADA. The grit classifiers on the duty flow path to the disposal bin will resume operation as soon as the corresponding grit pump starts operating. At the end of the grit extraction cycle, the grit classifier will continue to run for a preset time interval and then stop. The solenoid valve will open to allow for a preset backwash cycle while the classifier motor is running in the forward direction. The grit processing cycle will automatically repeat in conjunction with the associated grit pump system.

10.3.4 De-Gritted Wastewater Pumping


The headworks facility has a high demand for “service” water and is located at the extreme end of the site from the effluent service water pumping station. The objective of the de-gritted wastewater pumping is to provide screened raw wastewater for various applications using pumps installed in the Headworks Building. The de-gritted wastewater pumping system is designed to reduce plant service water demands by providing sufficient flow and pressure to the following high water demand processes: Sluicing channel flushing Vortex grit chamber fluidization Grit pump suction fluidization Pilot plant flow

The de-gritted wastewater pumps will be located within a pump chamber at ground level adjacent to the vortex grit chamber effluent channel. De-gritted effluent from the headworks is diverted to the chamber through an overflow weir installed on the side of the effluent channel.


The water demand from various processes is listed as follows: Sluicing channel flushing (10 L/s per sluicing channel, continuous) Vortex grit chamber fluidization (5 L/s, intermittent) Grit pump suction fluidization (10 L/s, intermittent) Pilot plant flow (assume 10 L/s, intermittent)

Table 50 summarizes the design criteria of the de-gritted wastewater pumping system used in the development of the Preliminary Design.



Table 54 Design Criteria for De-gritted Wastewater Pumping Parameter Criteria

Flow Requirement

Low Flow: 10 L/s - 1 sluicing channel

Average Flow: 20 L/s - 2 sluicing channels

High Flow: 30 L/s - 2 sluicing channels and fluidization (assume vortex and grit pump fluidization occur in sequence) Peak Flow: 40 L/s - 2 sluicing channels, fluidization and research building

System Pressure 42 m (60 psi)


Table 55 summarizes the preliminary design specifications for the de-gritted wastewater pumping system. Table 55 Preliminary Design Specification for De-gritted Wastewater Pumping

Item Specification

Wastewater Pumps

No. of units 3 (Lead, Lag, Lag)

Pump type Submersible Centrifugal Pump

Pump capacity 15 L/s at 42 m

Motor size 15 kW (20 hp)

Chamber Specifications

Chamber width 3.0 m

Chamber depth 1.2 m

Chamber height Approx. 6 m

Weir Gate

Dimension 1.5 m x 1.5 m

Elevation 284.6 m

No. of units 1


Under normal operating conditions, the de-gritted wastewater pumping system will operate in an automatic mode. The pumps will start and stop according to the system pressure. Since the system maintains a constant demand of at least 10 L/s, the pumps would be operated up and down the pump curve to match the flow demand. As the pressure drops in the system, additional pumps would be started until pressure reaches the desire level. Three pumps will be assigned as lead, lag and lag pumps. The control system will automatically assign individual pump duties based on pump availability and run time, and alternate pump operation between each duty cycle. Any pump may be selected as a duty pump.

10.3.5 Phosphorus Removal Chemical System


The objective of the phosphorus removal system is to remove orthophosphate to achieve the anticipated plant total phosphorus (TP) MOE average monthly effluent objective of 0.2 mg/L. The phosphorus removal system involves the addition of a phosphorus removal chemical to precipitate orthophosphate, which is subsequently removed as sludge in the primary and final sedimentation tanks. The phosphorus removal chemical used will be either ferric chloride or ferrous chloride. Provisions will be included to allow for the use of both chemicals simultaneously as part of the dual point dosing strategy. There are three available dosing locations, which allow for two (2) different dosing scenarios for operational flexibility:



1. Dosing Point No. 1 – Primary clarifier common influent channel 2. Dosing Point No. 2A – Aeration tanks, at the beginning of the second pass of each Aeration Tank 3. Dosing Point No. 2B – Secondary clarifier influent, at the end of the third pass of each Aeration Tank The dosing locations provide flexibility for dual point dosing. Two (2) dosing scenarios have been developed: Dosing Scenario No. 1 – Ferrous/Ferric chloride is dosed at the primary clarifier common influent channel

(Dosing Point No. 1) and the aeration tanks (Dosing Point No. 2A). Dosing Scenario No. 2 – Ferrous/Ferric chloride is dosed at the primary clarifier common influent channel

(Dosing Point No. 1) and the secondary clarifier influent (Dosing Point No. 2B).

10.3.5.1.1 Dosing Pumps

A total of eight (8) ferrous/ferric chloride metering pumps will be provided in a new building adjacent to the new headworks. Two (2) pumps (1duty, 1 standby) will be dedicated to primary clarifiers (Dosing Point No. 1) and six (6) pumps (3 duty, 3 standby) will be dedicated to aeration tanks and secondary clarifiers (Dosing Points No. 2A and 2B). The pumps for dosing points Nos. 2A and 2B will be assigned such that there is one (1) pair of pumps (1duty, 1 standby) for each pair of aeration tanks – one (1) pair in each of Plant 2, Plant 3, and Plant 4.

10.3.5.1.2 Storage Tanks

Ferrous/ferric chloride will be stored in four (4) fibreglass reinforced plastic (FRP) tanks, each with an operating capacity of 40,000 L. The tanks are insulated and heat traced. All tanks will be equipped with an ultrasonic level transmitter for level monitoring. Each ferrous/ferric chloride tank will contain a fill line, an overflow line, a drain line, a vent line and a pump suction line. Two (2) ferrous chloride storage tanks, of 40,000 L capacity each, will provide a total storage volume of 80,000 L for approximately 10 days of storage at average daily flows. Two (2) ferric chloride storage tanks, of 40,000 L capacity each, will provide a total storage volume of 80,000 L for approximately 14 days of storage at average daily flows. These available storage days correspond to the scenario in which only one chemical is used for dosing at both the front end and back end dosing locations.

10.3.5.1.3 Containment Areas

Containment areas will be provided for the ferrous/ferric chloride storage tanks and metering pumps. A sump pump will be provided in the tank containment area to pump out rainwater and incidental chemical spills. In the event of a tank spill or pipe leak in the tank containment area, the operator will follow spill response procedures. A high level float switch will be provided in the tank containment area to detect large spills that flood the tank containment area. When activated, the high level float switch will send an alarm signal and sends a signal to automatically close the motorized suction valves and stop the duty chemical pumps. Spills in the ferrous/ferric chloride pump containment area will be drained by gravity to the ferrous/ferric chloride storage tanks containment area sump. There will be a valve on the drain line which prevents backflow entering the pump room from the tank containment area. A float switch will also be provided in the pump containment area. When the liquid level reaches a pre-set level in the containment area, an alarm will be initiated at SCADA.

10.3.5.1.4 Ferric/Ferrous Chloride Tanks Fill Station

A fill hose connection will be installed for each ferrous/ferric chloride tank. A chemical unloading panel located on the outside wall of the tank containment area will be used to control filling and prevent overflows in the tank containment area. The unloading panel will contain a high level alarm which provides audio and visual indication when the “High Level” in any of the tanks is reached to inform the truck driver to stop the filling. The alarm will have a reset switch to shut off the audio signal, but the light will continue to flash until the chemical level in the tank drops below the set “High Level”. There is also a “Low Level” alarm for each tank to indicate to the operator which tanks need filling.




Table 56 summarizes the design criteria for the phosphorus removal chemical system used in the Preliminary Design. Table 56 Design Criteria for Phosphorus Removal Chemical System

Parameter Criteria

Chemical Type Ferric Chloride or Ferrous Chloride

Design Dosage 8 mg Fe2+/L 10 mg Fe3+/L

Chemical Storage

Number of Tanks 4

Days of Storage at Average Flow >10 days for each ferrous chloride >14 days for ferric chloride

Spill Containment Volume 110% of total tank volume plus allowance for rainwater


Table 57 summarizes the preliminary design specifications of the phosphorus removal chemical system. Table 57 Preliminary Design Specifications for Phosphorus Removal Chemical System

Parameter Criteria

Chemical Storage

Number of Tanks 4

Tank Material Fibreglass Reinforced Plastic

Tank Volume 40,000 l

Tank Dimension 3.66 m (12’) dia. x 4.57 m (15’) (H)

Chemical pumps

Pump Type Piston Diaphragm

Number of Pumps 8 (4 duty, 4 standby)

Pump Control VFD with manual stroke adjustment Pump Capacity

Primary Clarifier Dosing Aeration Tank/Secondary Clarifier Dosing

11 L/min @ 10 m TDH 6 L/min @ 10 m TDH


A common discharge header will be provided for each pair of storage tanks to feed the ferrous/ferric chloride pumps. The two (2) headers allow the simultaneous use of ferrous chloride and ferric chloride for dual point dosing. Each header will contain a motorized valve and duplex strainers. The two (2) headers will feed all eight (8) ferrous/ferric chloride metering pumps. Each ferrous/ferric chloride metering pump pair will be able to draw from either header. The two (2) headers will be connected via a manual valve that allows for the combining of the two (2) headers when either ferrous chloride or ferric chloride is stored in all four (4) storage tanks. The ferrous/ferric chloride metering pumps will normally operate automatically. Should a duty pump fail for any reason, the corresponding LCP will automatically shut down the duty pump and switch operation to the standby pump. Inlet and outlet valves to the eight (8) ferrous/ferric chloride metering pumps will normally be open, except during maintenance. The pumps discharge ferrous/ferric chloride to dosing points described above.



During normal operating conditions, the SCADA system the automatically adjusts duty chemical pump speed based on total flow rate measured by the influent flow meter and the dosage set by the operation to maintain required dosing flow. An effluent on-line phosphorus analyzer will provide monitoring data to the operator to assess the dosage rate/performance and adjust the setpoints as appropriate.

10.3.6 Channel Aeration


To optimize the screen performance, the screen channel widths are such that the approach velocity to less than 0.6 m/s. As a result, solid settling could occur during low flow conditions. The objective of the aeration system in the headworks channels is to prevent solids accumulation by keeping solids in suspension. The channel aeration system adopted for the Phase 3 Kitchener WWTP Upgrades is a coarse bubble aeration system that will provide adequate mixing of the raw wastewater. Coarse bubble diffusers will be mounted in the headworks common screen inlet and outlet channels. The channel aeration system will be programmed to operate periodically. The system will consist of one (1) duty blower and two (2) identical diffuser systems mounted on the channel bottoms. A blower will be installed on the first floor of Headworks Building. The total airflow will be distributed as follows: 66% by Zone 1 Manifold Assembly – mounted in the common screen inlet channels 34% by Zone 2 Manifold Assembly – mounted in the common screen outlet channels

Under normal operating conditions, the blower will be brought online and offline based on a time cycle or flow set-point of influent raw wastewater. The airflow will be directed through the distribution headers to the diffuser manifolds. The total airflow rate distributed for mixing into the channels will be detected by an insertion type flow meter.

10.3.7 Building Sump


The objective of the building sump system is to collect drainage water from the Headworks Building and pump it to the headworks influent channel. The building sump system, located on the ground floor of the Headworks Building, will consist of a sump and two (2) submersible sump pumps (1 duty, 1 standby). High/low level floats are provided for pump control and HWL alarm. The drainage from the Headworks Building will be generated from the following process areas: Conveyor drainage Odour control equipment drainage (low pH) Floor drains

Under normal operating conditions, the building sump will operate in automatic mode. The high/low level floats will be set up to start and stop the duty pump. Two (2) pumps will be assigned as duty and standby pumps. The duplex control panel will automatically assign individual pump duties based on pump availability and run time, and alternate pump operation between each duty cycle. Any particular pump may be selected as Duty 1 or Duty 2.



10.4 Odour Control Design


As part of the plant wide odour management plan and strategy, the Headworks Building will be equipped with a new odour control system (OCS), which will contain and treat odorous air. The OCS is comprised of two (2) sub-systems. The first subsystem is the conveyance system which comprises of ductwork and balancing dampers inside the Headworks Building. The OCS will treat odourous air from the following sources: Screen channels Mechanical screens Inlet/outlet distribution channel Grit/screening bin room Washer compactors

This network of ducts conveys the airflow to the second subsystem, the biofilter biological treatment system. The conveyance subsystem will contain the following equipment: One lot of ductwork One lot of balancing dampers Associated equipment such as expansion joints, supports, hangers etc.

A simplified flow schematic of the Kitchener WWTP headworks OCS is presented in Figure 14.

Figure 14 Flow Schematic for the Kitchener WWTP Headworks OCS

The biofilter biological treatment subsystem will consist of a bioscrubber and biofilter (referred to herein as the biofilter system) located outdoors to the northeast of the Headworks Building. The biofilter system will reduce odour contained within the foul process air for their sources by a minimum of 90%. The biofilter system contains the following equipment: One (1) bioscrubber One (1) biofilter treatment cell Two (1 duty, 1 standby) bioscrubber recycle pumps Freeze protection heater Two (1 duty, 1 standby) blower fans Media irrigation system

Two (2) fans (1 duty, 1 standby) will extract odourous air from the process areas of the Headworks Building and convey it towards the downstream biofilter system. The bioscrubber is the first stage of biological treatment. It aids in humidifying the process air to greater than 98% relative humidity and removing high concentrations of inlet H2S. The biofilter will follow the bioscrubber and further reduce H2S concentrations and other odour causing compounds such



as methyl mercaptan, and dimethydisulphide. The treated air will then proceed through the fans (operating as duty/standby) before being discharged via a dispersion stack to the atmosphere. Additional components required for the OCS are listed below: Biofilter/exhaust fan system foundation/slab New supports and foundations for odour control ductwork throughout new headworks facility Electrical supply, lighting, heat tracing and lightening protection (on stack) Site services including plant effluent line and drainage lines Control wiring, RPUs and programming

The electrical equipment and control panels are to be housed within the headworks electrical room.


The areas designated for direct odour control will be isolated from the building general ventilation and include channel and equipment headspaces. These areas are not meant to be occupied and do not require the same number of air exchanges as the building air. Therefore, the main objective of odour control is to maintain negative pressure inside these areas and contain the odours. In general, the covered headspaces of channels, tanks and distribution areas are ventilated at one (1) to three (3) air changes per hour. If the process area is provided with aeration, the head space ventilation will account for the aeration rate. This amount of air movement within unoccupied spaces will provide a good balance of maintaining negative pressure and lowering building operating costs. The process equipment in the screening building will include: screens, washer compactors and grit classifiers. The equipment headspace will be assumed as the same classification as the building and can be an odour source. Odour control take-off points will be provided to maintain the equipment under negative pressure. Based on previous experience, it is known that equipment odour control take-offs (screens, washer compactors, etc.) should not be over-ventilated to avoid extracting liquids, screenings, grit and other debris into the odour control ductwork. Typical odour control points for equipment range from 50 to 200 L/s and larger units may have multiple collection points. Air flow rates from the collection locations are presented in Table 58. Table 58 Odour Control Airflow Rates by Area

Area Air Flow Rate m3/h (cfm)

Inlet/Outlet Distribution channel 400 (235) Screening Channels 1217 (717) Grit/Screening Bin Area 3000 (1766) Washer Compactors 178 (105) Subtotal 4795 (2703) Total 5000 (2942)

Due to the potential for organic sulphides and mercaptans in the odorous air, a system consisting of a bioscrubber and biofilter will be installed for odour control. Standby equipment for the main mechanical components, such as pumps and fans, will be provided; however, no redundancy is provided for the biofilter unit itself.


Odourous air ductwork will be installed throughout the new headworks. Each take-off point will be sized for the necessary flow rate and be equipped with a manual damper for balancing. Consideration will be given at each take-off point to ensure operator accessibility and ease for maintenance and repair. Table 59 provides design specifications for the ductwork and associated equipment.



Table 59 Preliminary Design Specifications for Ductwork and Associated Equipment Parameter Criteria

Velocity 5.1 to 15.2 m/s

Temperature 5 to 40 °C

Pressure 0 to -4.0 kPa

Material SS316 or FRP

Balancing Damper

Type Manual butterfly with hand operator, lockable

Leakage ~5%

Expansion Joints Typical, synthetic rubber

Table 60 provides design specifications for the odour control units. Table 60 Preliminary Design Specifications for Odour Control Units

Parameter Criteria

No. of Units 1

Capacity, each 5,000 m3/h

Type Inorganic Media, Bioscrubber and biofilter

Media Volume 36.7 m3

Empty Bed Residence Time 24 s

Vessel Dimensions 3.66 m dia. by 7.9 m (H)

Overall Footprint 4.0 m (W) x 9.5 m (L)

Assumed Inlet Loadings

H2S 10 ppm (avg) / 25 ppm (peak)

Organic Sulphides <4 ppm (peak)

The biofilter system will be equipped with two (2) induced draught fans (1 duty, 1 standby). Each fan will be sized for a capacity of 5,000 m3/hr at 3.0 kPa static pressure. The corresponding motor size is 15 kW and will be equipped with a VFD to control the air flow through the system. Upstream and downstream motorized dampers will be provided for fan isolation for both fans. The current design locates these fans downstream of the biofilter. The control panels can be located on the structural slab close to the equipment as required for the controllers and to simplify the package supply process. All mechanical and electrical equipment associated with the biofilter system will be located above the regional flood elevation at 283.63 m. Table 61 provides preliminary design specifications for the odour control fans. Table 61 Preliminary Design Specifications for Odour Control Fans

Parameter Criteria

Flow Rate 5,000 m3/h

Static Pressure 3 kPa

Fan power (kW) 12

Motor power (kW) 15

Fan Type Centrifugal or as required

VFD Yes, 2 separate




The biofilter system will maintain a negative pressure draw on the headspace air within the influent sources by area listed in Table 58. In addition, general room HVAC in the grit/screening bin area will be treated by the biofilter system. Each foul air take-off point will be equipped with a manual balancing damper, which will be initially balanced during commissioning. If an odour branch header cannot be provided with individual dampers at each outlet, a balancing damper will be provided for the entire branch. The grit/screening bin branch will be provided with a modulating damper and interlocked with the HVAC system to ensure sufficient ventilation is provided when the room is occupied and unoccupied. The biofilter system will have two (2) modes of operation: manual and automatic. Normally, the biofilter system will run in automatic mode, where the fans and recirculation pumps are auto-alternated between duty and standby modes for system redundancy in case of required maintenance. The biofilter system PLC is connected to the plant-wide SCADA Ethernet network. There is no SCADA control of the biofilter system. Bed media condition will be evaluated on the basis of pressure differentials across the depth of the media. When 2 kPa of pressure loss across the media is approached, an alarm will be triggered on the plant SCADA system to indicate to the operators that inspection or maintenance on the bed is required. Pressure across the media will increase as the media ages and biomass and elemental sulphur build-up within it. At start-up, the pressure loss will be below 0.5 kPa. Media bed temperature will also be measured and an alarm will be triggered if the temperature reading in the bed falls below a certain level. Biofilter media irrigation will be performed for thirty (30) minutes a day on each cell in both biofilters. Water flow is recorded by a flow indicator on the water inlet line. A timer connected to a solenoid valve in the biofilter control panel opens the valve for the specified amount of time each day to allow water to flow to the irrigation spray nozzles. Plant service water will be used for the irrigation water. Bioscrubbers require water to be sprayed over the media surface continuously. Plant service water will be used for the bioscrubber make-up water. A nutrient dosing and water irrigation system that sprays water from the sump onto the media bed is included. The nutrient system will introduce nutrients to the water recirculation and spray system at a vendor recommended rate. The water spray will also aid in increasing air humidity and maintaining proper pH levels. To recycle spray water, a sump with duty/standby vertical sump pumps will be part of each bioscrubber cell. Supply make-up water will be available to replace the lost moisture. Local control will be provided for the pumps and the biofilter OCS control panel. The nutrient addition tanks and recirculation pumps are stored in a vendor supplied heated hotbox outside of the bioscrubber for protection from the elements. Winter freeze protection will be provided by a sump immersion heater. The immersion heaters will not be used as part of normal operation; they will be turned on at the biofilter system control panel when operating the biofilter system during the winter months. A temperature indicator in the sump will trigger an alarm if the sump water becomes too cold or too hot. The heater will start automatically when the operator entered low temperature set point is reached and will stop automatically when an operator entered high temperature limit is reached. As an additional safety measure in case of temperature control system failure, a high limit thermocouple on the heater sheath will turn off the heater when being run in manual or automatic mode to protect it and the chamber when a temperature of 50°C is reached


The new two (2) storey Headworks Building will be located near the site entrance, to the west of the new administration building and next to the truck loading bay, forming one (1) large complex. The building will be



constructed of cast-in-place concrete to the second floor elevation, and a steel frame with masonry infill above this level, complete with a full span girder crane for servicing the pumps and equipment. The first storey of the building will consist of a boiler room, storage room, blower gallery, and a below grade pumping station open to the second floor with a pair of wet wells, disposal bin room and a loading dock. The second storey will consist of an electrical room and an equipment and screening area, which will be separated from each other by a change in floor elevation. The process conduit will run in between the first and second storey, below the equipment area. Two (2) stairwells in the centre of the east and west walls of the building will provide the required exits and access points into the building. With the exception of the bin room and loading dock on the lower level, the rest of the space on the lower level will not be accessed at grade, rather only by the two (2) stairwells due to the level of the flood plain. The east stairwell will be the primary entrance and vertical circulation space for the building and will provide access to all levels, including the roof where the HVAC equipment will be located. The electrical room will be accessible from within the building and from the outside near the east stairwell entrance. Double doors will provide ease of equipment movement to and from the electrical room. Access to the pumping station will be via the west stairwell for personnel and by overhead girder crane for maintenance. Both entrances at either stairwell will be situated above the regulated flood elevation. External stairs bridge the difference in elevation. The monotony of the architectural volume of the Headworks Building will be broken up by three (3) horizontal layers of materials consisting of aluminum composite panels, metal siding and natural stone. The layers will create three (3) proportionate linear bands that will wrap around the building. The linearity will make the building appear sleek and slender. The volumes of the stairwells will further help to break the monotony. Long clerestory windows on the east and west facade will bring natural light into the equipment and screening areas and accentuate the linearity. A system of horizontal louvers will screen the HVAC equipment on the roof. A similar system of louvers beside the west stairwell will screen an odour control biotrickling filter. The louvers will add a layer of semi-transparency to the architectural volumes. The overall composition and proportions will be in harmony with the adjacent new administration building. Although LEED is not a requirement for this facility, sustainable ideas such as locally harvested and manufactured materials, effective day lighting, and a highly reflective roof will be incorporated into this facility.



Indoor design conditions are summarized in Table 62. Table 62 Indoor Design Criteria for the Headworks Building

Areas Criteria

General Areas

Mechanical Rooms 5.5 °C above outdoor temperature (summer) / 18 °C (winter)

Electrical Room 27 °C (summer) / 18 °C (winter)

Process Areas

Chemical Room 15°C ~18 °C (winter) / 5.5 °C above outdoor temperature (summer)

Process Areas 5~10 °C (winter) / 5.5 °C above outdoor temperature (summer)

The major HVAC units consist of two (2) mechanical ventilation systems (AHU-1 and AHU-2) mounted on the building roof top, one (1) condensing system on top of the electrical room, and two boilers on the first floor.



10.6.1.1 Heating Systems

A significant heating load is anticipated for the Headworks Building to achieve ventilation rates mandated by NFPA 820. A preliminary heating load analysis shows that the max heating load for the building will be approximately 3 million Btu/h range. Two (2) new gas fired cast iron hot water boilers (each sized for 60% of the load), pumps, glycol feeding system and expansion tanks will provide heating for building and AHUs. The loop for AHUs will incorporate variable speed pumps on a duty/standby basis to match the flow to the glycol demand; glycol recirculation loops will be utilized to ensure the heating coils do not freeze. Horizontal glycol unit heaters and glycol convection heaters will be placed in all areas, including stairs, mechanical rooms and overhead doors to provide supplementary heat for the building. Electrical unit heaters will be used to avoid hydronic systems within electrical rooms.


The ventilation rates for the various headworks facility areas are summarized in Table 63. Table 63 Ventilation Rates for the Headworks Building

Location And Function NFPA 820 Table and Row

NFPA Classification

NFPA Ventilation Rate Ventilation Rate and Additional Notes

New Screen Room/ Bin room Table 5.2 Row 1 Line A

Classified, Div. 1

No ventilation or ventilated at less

than 12 ACH

6 ACH (Occupied/Unoccupied) C/W localised Odour Control

New Blower Room (Main Floor) N/A Unclassified N/A Ventilation rate is based on heat relief

New Electrical Room/Control Room N/A Unclassified N/A Air conditioning unit

New Chemical Room N/A Unclassified N/A Ventilation rate is based on past experience and good engineering practice, 6 ACH for continuous ventilation and 12 ACH for emergency


Three indoor AC units will be installed in the MCC Room to prevent electrical equipment from overheating.



Potable water will be supplied to the building for sanitary and polymer dilution uses. Low water use plumbing fixtures and trim will be specified, and cross-connection control will be provided, in accordance with requirements of the OBC. Potable water will be metered at the building. Also, water heater will be provided for emergency eye/face wash.


Plant service water will be supplied to the building for treatment process uses. Service water will be provided with a self-cleaning strainer where the service water enters the building. A de-gritted wastewater pumping system has been designed for the Headworks facility to reduce plant service water demand.






Building floor drainage is collected in the building sump on the first floor and eventually pumped back to the screen channels. See building sump section for detail description.


Two (2) combination safety shower/eyewash units will be provided outside the chemical building by the chemical fill station and in the chemical pump room. The units will be provided with tempered water from emergency mixing valves and will be provided with a flow switch, light, and alarm bell. The alarm device will be the manufacturer’s standard unit and will to be coordinated with electrical for power requirements. The combination safety shower/eyewash unit located outside of the building will be a freeze-resistant unit. An emergency eye/face wash station and associated water heater will be provided in the southeast corner of the boiler room.


The electrical design of the Headworks Building is presented in detail in Section 17.







11. Tertiary Filtration (Contract 3b) A key component of the Kitchener WWTP Phase 3 Upgrades is a new tertiary treatment facility designed to achieve a total effluent phosphorus concentration objective of less than or equal to 0.2 mg/L. The Site Wide Facility Plan (AECOM, 2011) reviewed a number of alternative tertiary filtration technologies to provide phosphorus removal to meet the effluent concentration objective. Based on the review, disk filter technology was selected based on the following key advantages: Lowest capital and life costs Low headloss allowing incorporation within the existing plant hydraulic profile without intermediate pumping

Disk filtration equipment can vary significantly between vendors. Development of the preliminary design requirements for the building layout, backwashing and hydraulic profile was based on the Aqua-Aerobics Aquadisk® disk filter technology, to demonstrate that disk filter technology can be implemented in the physical footprint and hydraulics at the Kitchener WWTP. Appendix L provides information on this equipment. The building size and layout, and preliminary design details, will need to be modified to suit the selected equipment following filter pre-selection, which will be completed at a later stage in the design development.


The following key features will be incorporated in the tertiary treatment upgrades to protect process equipment and provide effective and reliable treatment performance: New disk filter tertiary treatment facility to provide capacity for the average flow of 123 MLD and peak

instantaneous plant flow of 307 MLD Tertiary filter bypassing for extreme flow events Backwash pumping and distribution to the primary effluent flow splitting chamber Influent channel modification to direct Plant 2, 3 and 4 secondary effluent flow to the tertiary treatment facility Effluent channels to direct tertiary treated flow to the UV disinfection facility Allowance for two (2) additional future filters to accommodate potential future plant expansion

A simplified process flow schematic of the tertiary treatment system is presented in Figure 15.



Figure 15 Simplified Process Flow Schematic of the Tertiary Treatment System

The new tertiary treatment facility will be located immediately west of the Plant 2 secondary clarifiers. This central location is convenient for combining Plant 2, 3 and 4 secondary effluent to the tertiary facility, and directing tertiary effluent to the adjacent UV disinfection facility. The preliminary footprint of the new building (with exterior channels) will be approximately 35 m x 27 m including effluent channels. The building is located within the floodplain and all entrances to the building (except the isolated loading bay) will be situated at 283.4 m to match the adjacent UV Building and protect all equipment in the event of a flood. The disk filters will be housed on the main floor of the building, while the backwash pumps, distribution valves and piping will be housed on the lower floor. Tertiary treatment drawings (Series 800) are contained in Appendix A. The preliminary process control narratives and process and mechanical equipment lists are presented in Appendix J and K, respectively.

11.2 Process Design

11.2.1 Disk Filters


The new tertiary treatment facility will be connected to the existing Plant 2 effluent channel by a new section of secondary effluent channel. The channel will be buried under the existing service road and open with grating on either side of the road for access. Due to the wide range of plant flows it will accommodate and the need to reduce overall headloss, the channel will be relatively large, such that flow will be low velocity under average flow



conditions. A retrievable channel aeration system will be used to allow intermittent scouring of the channel to mitigate higher solids loadings to the filters during peak flow due to scouring of settled solids. Filter effluent TP is in both soluble and particulate form; tertiary filtration can remove only particulate phosphorus. Given the 0.2 mg/L TP design objective, Aqua-Aerobics recommends flexibility be provided to add a low chemical dose upstream of the filters, so that soluble phosphorus is precipitated, and soluble concentrations remain below 0.1 mg/L at all times. Consideration will be given to the addition of this chemical dosing point during detailed design, following the completion of the pilot studies. If added, the dosing point design will be coordinated with the new coagulant storage and dosing system to be constructed adjacent to the new Headworks Building. Secondary effluent will enter the centre of the new tertiary building and be distributed into two (2) parallel channels of seven (7) disk filters each; flow will be received equally by each disk filter. The filters will be covered with removable covers with inspection hatches, to minimize filter flies and humidity in the building. During detailed design, options for manually cleaning the screens just upstream of the tertiary filter inlet, to protect the filters from sudden spikes in solids due to high instantaneous flow events or secondary clarifier upsets, will be considered. Flow will enter each filter through a 750 mm by 750 mm sluice gate provided for isolation, and a 2 m long rectangular overflow weir that will be used to control equal distribution of flow between individual filters. Each filter will be equipped with twelve (12) cloth media disks that are fully submerged in the secondary effluent. Secondary effluent will flow through the cloth filter into a hollow centre core. Tertiary effluent will overflow a rectangular weir to regulate low-level in the filter cell and keep the filter submerged under all operating conditions. An effluent sluice gate will be provided to enable positive isolation during extreme flow events when the effluent weir may become submerged. As the filter media accumulates solids, the level in the filter will rise and initiate a backwash sequence at high level. In the Aquadisk® design, the tertiary filter remains on-line and continues to filter secondary effluent throughout the backwash sequence. The Preliminary Design is based on 14 Aquadisk® disk filters initially for the design flow, with space provided to add two (2) additional filters in the future. Each unit provides a peak flow rated capacity of 22.7 MLD (6 mgd), for a total installed capacity of 318 MLD. Contingency filter capacity was not included in the Preliminary Design due to the additional costs for equipment and building space. This approach is feasible given the simplicity of the disk filter design (essentially a small gear drive similar to a secondary clarifier and cloth that requires replacement approximately every 5 years), the very low frequency of peak flow events, and the reported long term excellent operating record for disk filters. Under ADF conditions, eight (8) of the fourteen (14) units are required to handle peak diurnal fluctuations; therefore, sufficient filter capacity is available in the backwashing worst case scenario of all filters backwashing, which would take the equivalent of two filter units offline. An analysis was completed to further confirm the recommendation to provide total filter capacity without contingency, based on a minimal risk to effluent TP concentrations during peak flow events, even with one filter off-line. A conservative peak day design flow event of 294 MLD was selected. An hourly analysis was based on a continuous 24-hour wet weather flow of 171.3 MLD occurring in addition to the normal plant hourly diurnal profile. Using this scenario, hourly flows would exceed the 99.8 percentile design flow of 307 MLD more than 45 percent of the time, suggesting a very conservative evaluation of risk. The flow profile of this simulation is presented in Figure 16.



Figure 16 Peak Day Flow Scenario Used to Evaluate Risk to Effluent Quality with Tertiary Filter Bypass

Table 64 presents the calculated concentration of TP in the combined tertiary effluent and tertiary bypass (i.e., final effluent) in the peak day simulation scenario. Results show that even with one filter off-line, the combined final effluent TP concentrations during a conservative peak day flow event is only 0.21 mg/L. Based on this analysis, and factors mentioned above, the design based on total flow without contingency was selected. Table 64 Peak Day Effluent TP with one Tertiary Filter Off-Line

Parameter Flow TP Concentration

Tertiary Treated Effluent 284 MLD 0.2 mg/L

Tertiary Bypass (Secondary Effluent) 10.5 MLD 0.6 mg/L

Final Effluent 294.5 MLD 0.21 mg/L

0

50

100

150

200

250

300

350

12:00:00 AM 2:24:00 AM 4:48:00 AM 7:12:00 AM 9:36:00 AM 12:00:00 PM 2:24:00 PM 4:48:00 PM 7:12:00 PM 9:36:00 PM 12:00:00 AM

FLow

(ML/

d)

Firm Tertiary Capacity (295 ML/d)

Wet Weather Flow (171 ML/d)

Peak Day Diurnal Profile (294 ML/d)

Average Day Diurnal Profile (122.7 ML/d)

Tertiary Bypass Flow




Table 65 presents the design criteria of the tertiary disk filters as a basis for the development of preliminary design. Table 65 Design Criteria for Tertiary Disk Filters

Parameter` Criteria

Average (122.8 MLD) Hydraulic Peak (307 MLD)

Number of Filters 14

Design flow rate per filter 9 MLD 22.7 MLD

Effective Size of Filter Media 10 µm TSS Influent Effluent

15 mg/L <5 mg/L

20 mg/L <5 mg/L

Influent Soluble Phosphorus <0.12 mg/L <0.12 mg/L

Effluent Total Phosphorus <0.2 mg/L <0.2 mg/L

Hydraulic Loading Rate1 <16 m/h <16 m/h

Solids Loading Rate <10 kg/m2.d <10 kg/m2.d

Headloss per Filter <0.5 m including inlet and exit losses <0.5 m including inlet and exit losses

Estimated Backwash Flow <3% of influent Flow <5% of influent Flow Note: 1. Rate for U.S. Title 22 Certification for Water Re-use

11.2.1.3 Preliminary Design Specification

Table 66 presents the preliminary design specifications the tertiary disk filters based on Aquadisk®. Table 66 Preliminary Design Specification for Tertiary Disk Filters (Aquadisk®)

Item Specifications

Tertiary Disk Filters

No. of units 14

Number of Disks Per Filter 12

Filtration Area per Unit 60 m2

Influent Weir Length 2.0 m

Effluent Weir Length 2.5 m

Influent Isolation Sluice Gate 750 x 750 mm

Motor size 0.5 kW per unit

Influent Channel Specifications Number of Channels 2

Channel Dimensions (L x W x D) 23.1 m by 2.1 m by 2.2 m

Effluent Collection Channels Number of Channels 2

Channel Dimensions (L x W x D) 23.1 m by 1.5 m by 2.2 m

11.2.1.4 Operating Philosophy Instrumentation and Controls

All tertiary filters will normally be on-line to filter secondary effluent, which minimizes overall system headloss and ensures continuous turnover of water within the filter cell. Manual influent sluice gates will be used to isolate each filter for maintenance purposes. An actuated drain valve will be provided on the bottom of the filter to automatically discharge any settled solids with the backwash water (cycle timer). One control panel will be provided for every 2 (two) filters (i.e., 7 in total) to control filter backwashing and remove any solids that may settle in the filter. The control panels will communicate with a MCP to control the consolidated backwash water pumping system.



Intermittent chemical soaking may be required to reduce fouling of the cloth media. This practice is commonly accomplished by soaking the filter media in a chlorine solution. After the soaking period, the chlorine solution in the filter tank should be drained and pumped to the primary effluent flow splitting chamber to avoid the presence of any residual chlorine in the final effluent. Due to the infrequent need for chlorinated soaking (typically performed on an annual or less frequent basis) and chlorine strength deterioration, permanent chemical facilities are not provided. Sodium hypochlorite can be purchased in totes to supply the intermittent filter needs

11.2.2 Backwashing


The Aquadisk® filter backwashing system consists of a fixed suction shoe located on the face of each individual filter element connected to a downstream backwash water pump. As the filter rotates, the backwash water pump draws filtered water through the cloth dislodging captured solids and transporting the backwash water to the primary effluent flow splitting chamber. Backwashing of each filter is initiated based on a high level float switch in the filter cell. Filter backwashing is divided into three (3) segments to ensure effective cleaning of each filter segment. When a filter backwash cycle is initiated, the filter disk drive motor starts to rotate the filter and each segment is backwashed sequentially (i.e., one segment at a time). Each segment is isolated by an actuated valve. In the preliminary tertiary filtration system design, all backwash valves will be connected to a common header leading to the central backwash water pumping station. The header is oversized to minimize losses relative to the individual backwash header segment losses, to improve flow distribution when multiple filters are backwashing simultaneously. A total of five (4 duty/1 standby) non-clog, self-priming centrifugal pumps complete with VFDs will provide backwashing for the filters. The pump discharge head has been sized to allow transfer through yard piping to the primary clarifiers without additional intermediate pumping.


Table 67 summarizes the design criteria for filter backwash system. Table 67 Design Criteria for Filter Backwashing

Parameter Criteria

Simultaneously Backwash Water Flow Minimum (1 filter) Maximum (16 filters – future)

16.4 L/s 263 L/s


Table 68 presents the preliminary design specification of the filter backwash system.



Table 68 Preliminary Design Specifications for the Filter Backwashing System Item Specifications

Backwash Valves

Diameter 100 mm Number Per Filter Total

3 backwash/1 settled solids

56 Common Backwash Suction Header Size 450 mm

Backwash Pumps

No. of units 5 (4 duty, 1 standby)

Type Non-clog, Self-prime Centrifugal Pump Capacity Range (each) Minimum Maximum

16.4 L/s @ 7.1 m TDH 65.6 L/s @ 15.8 m TDH

Drive VFD

Suction /Discharge Flange 150 mm/150 mm

Motor size 29.8 kW (40 HP)


Filter backwashing will be initiated based on a high level float switch in the filter chamber. A second high-high level float will alarm operating staff of a potential problem with the filter. When a backwash sequence on a filter is initiated, the following operating sequence will occur based on the filter control panel logic: 1. Filter drive starts to rotate disks 2. Backwash water valve on the first filter segment opens 3. Backwash request is sent to the backwash pump master control panel 4. Segment 1 backwashes for “X” minutes (set to ensure one complete revolution of disk filter) 5. Segment 2 valve opens and Segment 1 valve closes 6. Segment 2 backwashes for “X” minutes (set to ensure one complete revolution of disk filter) 7. Segment 3 valve opens and Segment 2 valve closes 8. Segment 3 backwashes for “X” minutes 9. Backwash request to backwash pump master control panel is cancelled 10. Segment 3 valve closes 11. Filter drive stops No communication will be provided between individual filters to coordinate backwashing. As a result, all filters may backwash simultaneously if required. The backwash pump MCP will receive backwash requests from each filter control panel. The MCP will adjust the total backwash water flow set-point based on the sum of each filter requesting backwash. The Duty 1 backwash water pump will start and adjust its speed to maintain the set-point flow rate based on a magnetic flow meter in the downstream header. If one pump cannot maintain the target flow rate, Duty 2 pump will start. A similar sequence will continue for both the start-up and shut-down of individual pumps to maintain the target backwash water flow. A duty rotation cycle for the pumps will be provided in the control panel. SCADA will trend filter backwashing frequency for each filter on a daily basis to allow operators to monitor for potential flow distribution differences, media plugging or backwash water shoe sealing issues.



11.2.3 Tertiary Bypass


Due to its history of very high peak flow events and the limited hydraulic profile at the Kitchener WWTP, a tertiary bypass will be provided to minimize the risk of flooding of the secondary clarifier launders and to manage peak flow in excess of the tertiary treatment capacity. The design incorporates the following bypass provisions: Two (2) actuated weir gates One emergency static bypass overflow weir

Normally, the actuated weir gates will be in a fully raised position such that all flow receives tertiary treatment. In the event of a high level upstream of the filters, the actuated weir gates will modulate to maintain the upstream level. In the event of weir gate failure or extreme flows that cannot be handled by the weir gates alone, a high level emergency, passive overflow is provided. The overflow elevation is 75 mm below the Plant 2 secondary weir elevation to minimize the risk flooding the secondary effluent launder flooding. During emergency conditions, the emergency overflow would allow flow to bypass the tertiary facility, but the Plant 2 secondary clarifier weirs would likely be flooded; therefore, plant flow would be contained within the concrete walls (i.e., no overflow to land), but secondary clarifier performance would diminish.


Table 69 presents the design criteria for the tertiary filtration bypass. Table 69 Design Criteria for Tertiary Bypass System

Parameter Criteria

Peak Instantaneous Plant Design Flow 430 MLD

Tertiary Filter Capacity with 2 units off-line 270 MLD

D7esign Tertiary Bypass Capacity 150 MLD


Table 70 presents the preliminary design specifications for the tertiary bypass system.

Table 70 Preliminary Design Specifications for Tertiary Bypass System Parameter Criteria

Weir Gates

Dimension 1.5 m wide by 1.8 m deep

Resting Position 218.60 m

Full Open Position 216.80 m

Design High Water Level Upstream of Weir 218.30 m

Maximum Flow per Channel 80 MLD

Fixed Overflow Weir

Length 5.0 m

Elevation 218.60 m

Flow capacity at 50 mm head 8.9 MLD




An ultrasonic level sensor will be provided in the inlet channel to each bank of filters (2 in total) to control the actuated weir gates. Normally, the weir gates will rest 100 mm above design high water level so there will be no filter bypass. Once a high level set-point is reached in the influent channel (as measured by the ultrasonic level sensor), the weir gate will start to travel downward (open) and modulate to maintain the upstream high level set-point in the channel. Once the gate position reaches the high water level (indicating no bypass is required) and stays in this position for more than 30 minutes, the gate will rise 100 mm to resting position to eliminate filter bypass due to minor water level fluctuations and/or turbulence. An ultrasonic level sensor will also be located at the fixed passive overflow weir to warn operators when a high level overflow is occurring. The tertiary filter bypass flow rate will be estimated as follows: Difference between inlet channel level and actuated weir gate position to determine the driving head over a

standard rectangular weir Level over the passive weir

11.2.4 Miscellaneous Process Systems

11.2.4.1 Channel Aeration

The objective of the aeration system in the tertiary filter influent channels is to avoid solids accumulation by keeping all solids in suspension. The channel aeration system used in the Kitchener WWTP Phase 3 Upgrade is a retrievable coarse bubble aeration system that will provide adequate mixing of the secondary effluent upstream of tertiary filtration. The system will operate intermittently to suspend settled solids and minimize the potential for higher solids loading rates during peak flow from channel scouring. The system consists of one (1) duty blower and a retrievable diffuser system mounted on the side of the tertiary influent channels. The blower will be located on the main operating level of the tertiary filtration building. The total airflow to the channels is designed for 8.3 L/s•m (0.5 m3/min per line m), consistent with MOE Guidelines (2008). Under normal operating conditions, the blower will be brought on-line and off-line based on a cycle timer. The airflow will be directed through the distribution headers to the diffuser manifolds. The blower will be constant speed and air flow distribution will be controlled by orifices in the manifold piping and manifold isolation valves.

11.2.4.2 Process Sump System

The objective of the process sump system is to collect drainage water from the tertiary filtration facility and pump it, along with the backwash water, to the primary effluent flow splitting chamber. The process sump system will consist of a wet well and two (2) submersible pumps (1 duty, 1 standby). A level transmitter and high/low level floats are provided for level monitoring and pump control. The wet well is located in the basement level on the east side of the tertiary filtration building. The drainage from the tertiary filtration facility includes equipment wash-down and drainage of tanks/backwash lines for maintenance.



11.3 Equipment Procurement

Numerous disk filtration equipment vendors are available. The configuration, capacity and backwashing approach varies considerably for each type of equipment. As an example, both Veolia (Hydrotech Discfilter) and Siemens (Forty-X™ Disc Filter) offer system configurations with up to 100 m2 of surface area per unit compared to 60 m2 for each Aqua-Aerobics filter. The use of such higher surface area configurations will increase the physical dimensions of individual filters, but reduce the total number of filters required. To ensure the design can be customized and optimized for the selected vendor, disk filter pre-selection is recommended at the start of detailed design. The pre-selection process should be an evaluated bid tender that consider both technical and financial factors. As discussed with the Region, it is recommended that the Region complete evaluate a long list of tertiary filter equipment against an established set of criteria, such as applications of comparable size, demonstrated experience, performance and maintenance requirements. The Region can also consider pilot studies of the short-listed equipment that meets the criteria, as part of the pre-selection process.


The tertiary filtration building will be situated on the northeast end of the WWTP, northeast of the existing UV disinfection building. The building will be one (1) storey in height and will house a large filter room. The filter room will have a suspended grated floor supported on steel framing with self-contained filters protruding through the grating. The building will also include an electrical room, control room, chemical room, internal influent channel and external effluent channels. The building will be constructed with a concrete column and beam structure with masonry infill walls. The roof will be flat and constructed with pre-cast tees. An overhead girder style crane will run down the full length of the filter room to accommodate the service and maintenance of the filter equipment. Elevated equipment platforms will be provided around the filter equipment for ease of maintenance. The interior will feature walls and ceilings finished with epoxy coatings. The structural floor below the level of the raised grating and steel framing will be constructed with insulation sandwiched between two (2) layers of cast-in-place concrete and will be finished with a protective epoxy coating. The architecture of the building will be similar to that of the adjacent UV disinfection building currently under construction. Although LEED is not a requirement for this facility, sustainable ideas such as locally harvested and manufactured materials and effective day lighting will be used in this facility.



Indoor design conditions are summarized in Table 71.

Table 71 Indoor Design Criteria for the Tertiary Filtration Building Areas Criteria

Process Areas 10 °C unoccupied mode and 18 °C for occupied mode (winter) 5.5 °C above outdoor temperature (summer)

Electrical/Control Room 25 °C (summer) / 22 °C (winter) Note: The above design parameters might have a deviation of about +/- 10%, dependent on space and application.




A preliminary heating load analysis estimates that the maximum heating load for the tertiary filtration building will be approximately 1.0 million Btu/h. This estimate should be considered as an “order of magnitude” only, because the actual size will be dependent on the filter vendor selected and final building footprint requirements. Mechanical HVAC will be further investigated during detailed design. The loop for AHUs incorporates variable speed pumps on a duty/standby basis to match the flow to the heating water demand, glycol recirculation loops are utilized with intermediate plate and frame glycol hot water heat exchangers to ensure the heating coils do not freeze. Horizontal or vertical discharge glycol hot water unit heaters or glycol hot water convection heaters are used for stairs and rooms with overhead doors. Electrical unit heaters are recommended within electrical rooms to avoid hydronic systems around MCCs and control panels.


The ventilation rates for the tertiary filtration building are summarized in Table 72. Table 72 Proposed Ventilation Rates for the Tertiary Filtration building

Location and Function NFPA 820 Table and Row NFPA Classification NFPA Ventilation Rate Proposed Ventilation Rate and

Additional Notes

Process Areas N/A Unclassified N/A Ventilation rate is based on 3 ACH or heat relief if required

Electrical Room/Control Room N/A Unclassified N/A Ventilation rate is based on heat relief and AC recommended


The areas that require significant heat dissipation, such the electrical and control rooms, will be provided with dedicated mechanical cooling systems (i.e., DX split unit).



A water service loop is required for building potable water. The maximum water pressure from serving potable water system will be 550KPa. Interior hose valves for non-process areas are based on Plant Standard.





Floor drains and hub drains have primed P-traps. Ganged traps are provided where allowed by codes otherwise individual traps are provided. All drains are directed to the duplex sump pump system in the Tertiary Filtration Facility.




The tertiary filtration building is equipped with a duplex sump pump.


Not applicable.


The electrical design of the digested sludge transfer pumping system is presented in detail in Section 17.







12. Outfall (Contract 3b) 12.1 General Description

A new outfall composed of new 1950 mm diameter concrete effluent pipe (overland and in-river) and 1800 mm diffuser structure will be constructed to accommodate the design peak flow of 430,000 m3/d. The new outfall and diffuser structure will be constructed downstream of the existing outfall pipe, as shown in Figure 17. The existing outfall pipe and diffuser structure within the Grand River will be removed.

Figure 17 New and Existing Kitchener WWTP Outfalls

The new outfall and diffuser structure have been designed with the following considerations:

Minimize headloss through the pipes Promote vertical and lateral effluent/river water mixing Minimize impact to natural habitats (i.e., reduce river bed scouring) Minimize impact to river recreational use

Outfall drawings (Series 800) are contained in Appendix A.

12.2 Existing Outfall

The overland portion of the existing outfall at the Kitchener WWTP consists of a 1200 mm diameter concrete pipe that conveys effluent from the existing chlorine contact chamber to the Grand River. According to field data included in the Stantec Assimilative Capacity Study (May 2010), the existing outfall within the river is 900 mm diameter. The Stantec Study (2010) indicated that the existing diffuser structure has two (2) ports, with one (1) port facing up stream and one (1) port facing downstream. The majority of plant effluent is discharged from the downstream facing port and minimal flow is discharged from the upstream facing port. The new UV disinfection building and effluent pumping station (currently under construction) include an effluent pumping station to lift effluent during high flow periods and/or high river water level conditions.

New Outfall

Existing Outfall



12.3 Design Criteria

The new outfall is designed to convey disinfected effluent from the new effluent pumping station (EPS) to the Grand River. Under normal circumstances, effluent from the EPS outlet channel will flow by gravity to the river. If the level in the outlet channel reaches a high level setpoint, the effluent pumps will be activated to provide the additional head required in the outlet channel; based on analysis performed during the Phase 2 upgrades (CH2MHill, 2010), the effluent pumps are activated at a flow of 150,000 m3/d.

Table 73 summarizes the available pressure head between the EPS outlet channel and the river at various flow conditions. Table 73 Available Head at Kitchener WWTP Outfall Flow (m3/d) Level at EPS (m) River Level (m) Available Head (m) Note

100,000 277.69 277.40 0.29 Assume river at typical river level; effluent pumps NOT running

150,000 277.69 277.40 0.29 Assume river at typical river level; assume EPS at low level; effluent pumps NOT running

200,000 283.52 282.37 1.15 Assume river at design flood level; effluent pumps running

400,000 286.94 282.37 4.57 Assume river at design flood level; effluent pumps running Note: water levels at different flows based on Phase 2 Upgrade Hydraulic Profile (July 2010) (CH2MHill, 2010)

The new diffuser structure consists of an 1800 mm diameter diffuser barrel with six (6) downstream facing 600 mm diameter nozzles. Table 74 summarizes the calculated maximum headloss through the outfall at various flow conditions.

Table 74 Headloss through New Kitchener WWTP Outfall

Flow (m3/d) Headloss (m) Available Head (m)

123,000 0.13 >0.29

150,000 0.20 0.29

270,000 0.63 >1.15

430,000 1.61 >4.57

Six (6) diffuser nozzles on the diffuser structure, depicted in Figure 18, will evenly distribute the effluent flow into the surrounding river flow, promoting fast vertical and lateral effluent/river water mixing. The diffuser nozzles will be designed to discharge effluent water approximately parallel to the river bed. The diffuser structure will be partially buried in the riverbed to minimize intrusion into the river. The top of the new diffuser barrel, including the nozzles, will be approximately 1 m above the river bed, compared to the existing diffuser structure, which is approximately 2.1 m above the river bed.



Figure 18 Cross Section of Diffuser Structure

Computerized fluid dynamic (CFD) modeling will be conducted to further refine the outfall diffuser design.



12.4.1 Environmental Considerations

The existing nature trail will be closed to the public for a period of several months during the construction period. Construction will require the removal of existing vegetation along the pipe route. New native vegetation will be used to restore the area and re-instate the natural shielding of the WWTP from the trail.

A fish habitat study will be conducted during detailed design and a monitoring and restoration plan will be implemented during construction.

As the project and construction progress, steps will be taken to protect the environment in the surrounding natural habitat, including identifying and preserving wildlife that are at risk. In addition, communication with agencies including GRCA, DFO, and MNR, will be maintained to ensure compliance to all relevant regulations.



13. Secondary Treatment (Contract 4) 13.1 General Description

The secondary treatment upgrades will incorporate features to improve settleability and provide for step feeding during extreme wet weather to avoid plant upsets. New Plants 3 and 4 will be constructed and the existing Plant 1 will be decommissioned and demolished. The new Plants 3 and 4 will be identical in design. Each plant will consist of two (2) aeration tanks, four (4) circular secondary clarifiers, and one (1) RAS/WAS pumping station. The aeration system of Plants 3 and 4 will be equipped with seven (7) new blowers (6 duty, 1 standby), fine bubble membrane diffuser grids and associated instrumentation. The new blowers will be housed in the existing blower building. The RAS/WAS pumping stations of Plants 3 and 4 will be located adjacent to their associated aeration tank effluent channel to provide common wall construction and interconnection for tunnel access. A simplified process flow schematic of the Plant 3 and 4 secondary treatment system is presented in Figure 19.

Figure 19 Simplified Process Flow Schematic of the Plant 3 and 4 Secondary Treatment System (One

Treatment Train Shown)



Plants 3 and 4 will provide a total capacity of 82 MLD and Plant 2 will be de-rated to a capacity of 40 MLD. Plants 3 and 4 have been configured to operate as two (2) process trains as shown on Figure 20. Flow will be split downstream of the existing primary clarifiers into three (3) flow streams that will be transferred to each plant.

Figure 20 Kitchener WWTP Plants 3 and 4 Simplified Schematic

In addition to the Plants 3 and 4 RAS/WAS pumping stations, a new Plant 2 RAS/WAS pumping station will be constructed on the site of the existing RAS/WAS screw pumping station. All three (3) RAS/WAS pumping stations use the same design concept, each consisting of six (6) new centrifugal RAS pumps (4 duty, 2 standby) and two (2) new centrifugal WAS pumps (1 duty, 1 standby). The existing Plant 2 RAS/WAS screw pumping station will be demolished. Secondary treatment drawings (Series 500) are contained in Appendix A. The preliminary process control narratives and process and mechanical equipment lists are presented in Appendix J and K, respectively.

13.2 Process Design

13.2.1 Primary Effluent Flow Splitting Chamber


The Kitchener WWTP is currently serviced by two (2) activated sludge plants: Plant 1 and Plant 2. Effluent from the existing primary clarifiers is currently diverted to Plant 1 aeration tanks, via a 1050 mm pipe, and Plant 2 aeration tanks, via a 900 mm pipe.



Once Plants 3 and 4 are commissioned, primary effluent flow will be diverted to the new flow splitting chamber and distributed to Plants 2, 3, and 4. The new flow splitting chamber will be built attached to the west end of the primary clarifiers. Primary effluent will be diverted to the new flow splitting chamber from the existing primary clarifier launder. Flow exiting the chamber will be conveyed to Plants 2, 3 and 4 via dedicated 900 mm diameter pipes.


Table 75 presents process design criteria for the primary effluent flow splitting chamber. Table 75 Design Criteria for the Primary Effluent Flow Splitting Chamber

Parameter Value

Average Raw Sewage Flow (MLD) 123

Peak Instantaneous Flow (MLD) 430

Number of Flow Splits 3

Flow Control Mechanism Motorized Weir Gates/Stop Logs


Table 76 presents Preliminary Design specifications for the new primary effluent flow splitting chamber. Table 76 Preliminary Design Specifications for the Primary Effluent Flow Splitting Chamber

Item Specification

Chamber Dimensions Length: 8.4 m Width: 5.6 m Height: 5 m

Weir Length 2.1 m

Weir Gate Dimensions 2.4 m x 2.4 m

Influent Channel 2 x 900 mm dia.

Effluent Pipes 3 x 1500 mm dia.


Three (3) weir gates will be utilized to achieve flow splitting between Plants 2, 3 and 4. Under normal operating conditions, all three (3) weirs will be set at the same elevation to achieve equal splitting. However, should the flow to a specific plant need to be altered or terminated, the corresponding weir gate will be adjusted accordingly. The ultrasonic level sensor and gate position indicator can be used to approximately measure flow to each plant.

13.2.2 Plant 3 and 4 Aeration Tanks


Plants 3 and 4 are designed to be nitrifying activated sludge plants with partial oxidized nitrogen removal to reduce energy consumption and promote the growth of a well-settling sludge. Plants 3 and 4 will consist of two (2) 3-pass plug flow aeration tanks with step-feed capability (see Figure 20). A three-stage anoxic selector will be located at the front end of Pass 1 of each aeration tank. The readily biodegradable substrate will be used by denitrifying bacteria as carbon source before the substrate enters the aerobic zone, depriving obligate aerobic filamentous bacteria of a competitive advantage, generating a well settling sludge.



The anoxic selector zones will be equipped with submersible mixers to ensure solids suspension. The submersible mixers will be positioned such that operators can access the mixers from walkways for equipment maintenance or removal. The mixer equipment package will include integral electric motor, mounting assembly and lifting davit to allow for mixer removal and height and angle adjustment without entering or draining the selector. The aerated zones of the aeration tanks will be equipped with grids of fine bubble membrane diffusers to distribute process air supplied by aeration blowers. The Plant 3 and 4 aeration blowers will be installed in the existing (currently under construction) blower building located between Plants 2 and 3. The first selector cell of Plants 3 and 4 will receive primary effluent and RAS. The primary effluent includes tertiary filter backwash and WAS thickening filtrate, which will be added to the primary effluent flow at the flow splitting chamber. The centrate from the WWRMC will be added directly to Plant 2. The Plant 3 and 4 aeration tank design provides the flexibility for conversion to a Modified Ludzack Ettinger (MLE) process to accommodate a possible future total nitrogen limit at the Kitchener WWTP. To modify the process, the aerated section of Pass 1 of each aeration tank can be converted to a race-track anoxic zone by discontinuing aeration in Pass 1 and adding a racetrack baffle and building a weir between Pass 1 and Pass 2. The anoxic selector is designed with three (3) compartments to reduce short-circuiting, facilitate plug flow, and optimize the denitrification rate. Each compartment will have a submersible mixer installed for mixing. Liquid level in the anoxic selector is dictated by the elevation of the overflow weir. The weir ensures consistent flow velocity across the tank width and allows any foam/scum to be carried downstream to the aerobic zone, minimizing build-up of foam/scum on the liquid surface of the tank. The foam/scum cascaded over the weir from the anoxic selector into the aerobic zone will be dispersed by the aeration system. To accommodate these future modifications, the aeration tank hydraulics provide for adequate headloss between Pass 1 and Pass 2 of each tank and space has been provided for the future installation of mixed liquor recycle pumps. Conversion of the Plant 3 and 4 aeration tanks to an MLE process will reduce the capacity of the aeration tanks. Space has been provided for the addition of a fifth similarly sized aeration tank to provide additional aeration tank capacity. The aeration tank influent channels can be combined and extended in the future to allow for flow split between the five aeration tanks.


Table 77 presents process design criteria for the Plant 3 and Plant 4 aeration tanks.



Table 77 Design Criteria for the Plant 3 and Plant 4 Aeration Tanks Parameter Value

Average Raw Sewage Flow (MLD)1 82 (41 per Plant)

Peaky Hourly Treated Flow (MLD) 205 (102 per Plant)

Peak Instantaneous Flow (MLD) 1 288

Design Max RAS Rate (% Average Daily Flow) 100%

Aerobic Solids Retention Time (SRT) (days) 10

Total SRT (days) 11

Hydraulic Retention Time (HRT) at Average Raw Sewage Flow (Hours) 12

Average Design MLSS (mg/l ) 3,500 Note: 1. Does not include in-plant recycle flows


Table 78 presents Preliminary Design specifications for the new Plant 3 and Plant 4 aeration tanks. Table 78 Preliminary Design Specifications for the Plant 3 and Plant 4 Aeration Tanks.

Item Specification

Flow Regime Normal Operation Extreme Events (>99%ile)

Plug-Flow Step-Feed

Number of Modules Number of Tanks/Module

2 2

Number of Passes / Tank 3

Anoxic Selector Dimensions Stages per Tank Dimensions (L x W x D) Volume (total per tank)

3

7.8 m x 7.5 m x 6 m (per stage) 1053 m3

Anoxic Selector Submersible Mixers Number of Mixers per tank Mixer Capacity 1

3 (one per stage)

1.7 kW each Aerobic Zone Dimensions (per tank)

Pass 1 Pass 2 and 3 Volume per Tank

55.3 m x 7.5 m x 6 m

77.5 m x 7.5 m x 6 m (each) 9463 m3

Total Aeration Tank Volume 10,516 m3 (per tank) 42,064 m3 (total Phase 3)

SRT 10 days (aerobic) 11 days (total)

HRT (at average flow) HRT (at peak flow)

12 hours 5 hours

Note: 1. 13 kW/103 m3 (Metcalf & Eddy Fourth Edition, Page 753 – typical power requirement for mechanical mixing in the anoxic zone)


Under normal operation, tertiary filter backwash and WAS thickening liquor will be combined with the primary effluent upstream of the aeration tank influent at the Primary Effluent Flow Splitting Chamber. The combined flow is split proportionally between Plants 2, 3 and 4 and flows by gravity through dedicated pipes to each Plant. Flow to Plants 3 and 4 enters distribution chambers dedicated to each plant and is split between two (2) adjacent aeration tanks, as shown in Figure 21.



Figure 21 Plant 3 and Plant 4 Aeration Tank Distribution Channels Schematic

Plant 3 and 4 will operate as separate plants using identical operating principles. RAS from the secondary clarifiers will be pumped to the RAS channels, as shown in Figure 20. RAS will flow through the channels to the head of the aeration tanks, where it will be split between two (2) adjacent aeration tanks. RAS will be combined with incoming primary effluent flow and enter the anoxic selector of the aeration tanks via a mixing chimney. The feed will pass through the anoxic selectors followed by the aerated zones of the aeration tank. Submersible mixers will be provided in the selectors to maintain solids suspension. Oxygen will be distributed through the aerated zones of the aeration tanks via a fine bubble diffuser system. Flow distribution and liquid level control in the aeration tanks is accomplished by distribution channels, gates and weirs as summarized below: One (1) flow distribution channel is provided for every two (2) aeration tanks. Flow will be piped from the Primary

Effluent Flow Splitting Chamber to each Aeration Tank Flow Distribution Channel, where weir gates will be provided to divide flow between the aeration tanks.

RAS from each of Secondary Clarifiers 3-1 to 3-4 and 4-1 to 4-4 will be pumped to a RAS Return Channel (3 or 4) to the first anoxic selector cell in the aeration tank. Weir gates will be provided at the end of each channel to distribute RAS between the tanks and combine with primary effluent.

At the end of Pass 3 of each aeration tank, the mixed liquor will flow over a fixed full width weir (one per aeration tank) to a combined Aeration Tank Effluent Channel. One (1) channel will be provided for each pair of aeration tanks. Mixed liquor will then flow from the chamber to one (1) of four secondary clarifiers.

In the event of extreme flow conditions, step feed capability is provided by an automated weir gate at the end of Pass 2 of each tank. When the automated weir is lowered, primary effluent will be equally distributed between the Pass 1 inlet and the Step Feed Inlet.

Stop logs are installed between the two (2) aeration tank effluent channels to divide the Plant 3 and Plant 4 channels. In the event that an aeration tank or secondary clarifier is taken out of service, the stop logs may be removed to evenly distribute the flow between Plant 3 and Plant 4. This procedure will require a RAS return flow transfer to ensure similar Mixed Liquor Suspended Solids (MLSS) concentrations in the remaining tanks.



MLSS analyzers are installed in each aeration tank effluent channel. Target MLSS concentrations and solids retention time (SRT) are maintained through periodic adjustment of the WAS flow rate.

13.2.3 Plant 3 and 4 Process Air System


The purpose of the process air system is to provide oxygen to meet biological oxygen demand and mixing requirements in the aeration tanks. Aerobic bacteria convert oxygen demand to energy and biomass. Nitrifying bacteria oxidize ammonia to nitrite and nitrate. Seven (7) aeration blowers with VFDs will be located in the Blower Building to provide aeration to Plant 3 and Plant 4. Six (6) blowers are required to provide aeration demand and one (1) additional blower is provided as a standby unit. Two (2) of these blowers have been installed on an interim basis for aeration to Plant 1 and will be modified for use at Plant 3 and Plant 4 once Plant 1 has been decommissioned. In addition, five (5) existing blowers are located in the Blower Building and provide aeration to Plant 2. The seven (7) Plant 3 and 4 blowers discharge to a main common air header, which will transport air to Plant 3 and Plant 4. Air supply lines branch off from the main common air header and direct pressurized air to each pass of each aeration tank as shown in Figure 22. A separate discharge header is installed for Plant 2. The Plant 2 and Plant 3 aeration systems will be independent.



Figure 22 Plant 3 and Plant 4 Aeration System Configuration

To provide substantial and efficient mass transfer of oxygen to the liquid, grids of fine bubble diffusers will be used in each aeration tank. The blowers are brought online and taken offline, and the discharge capacities controlled, to control the dissolved oxygen levels in the aeration zones.


Table 79 presents process design criteria for the process air blowers. Aeration requirements were calculated for both summer and winter temperatures and average and peak contaminant loading. Process modeling was used to determine the oxygen requirement for each pass of the aeration tank to allow for the design of a tapered diffused aeration configuration. Each scenario accounted for diurnal variation in contaminant load such that a daily range of expected oxygen requirements could be determined for each scenario.



Table 79 Design Criteria for the Plant 3 and Plant 4 Oxygen Demand

Scenario Flow Diurnal Condition

Contaminant Loading

Condition

Wastewater Temperature

°C

Pass 1 Oxygen Demand

(kg/day/pass)


(kg/day/pass)


(kg/day/pass)

Total (kg/day/tank)

1

Average Max day 1 10 2800 3134 2243 8177

Max Max day 1 10 3202 3554 2790 9546

Min Max day1 10 2120 1925 1611 5655

2

Average Max day 1 20 3678 3054 1877 8609

Max Max day 1 20 4209 3981 2096 10286

Min Max day1 20 2354 1860 1689 5904

3

Average Average day 10 2197 2459 1847 6504

Max Average day 10 2681 2830 2342 7854

Min Average day 10 1645 1562 1295 4502

4

Average Average day 17 2657 2548 1608 6813

Max Average day 17 3219 3335 2116 8673

Min Average day 17 1825 1503 1335 4663 Note: 1. Max day contaminant load is equal to 1.25 average loading

Table 80 presents process design criteria for the fine bubble diffuser system. For each pass, the average and maximum loading condition and the minimum aeration requirement for mixing was evaluated. The maximum of these conditions governed the diffuser density. The main air header control valve and individual drop leg valves provide flexibility to adjust air flow to each zone based on oxygen demands. Table 80 Design Criteria for the Plant 3 and Plant 4 Fine Bubble Diffuser System (per tank)

Scenario Condition Diffuser Air Flow

Pass 1 (sm3/d/tank)1



Total per Tank (sm3/d/tank)1

Average Day Load Wastewater Temperature = 17°C

Mixing2 21,444 30,634 30,634 82,712

Average 68,307 62,163 39,229 169,699

Peak 82,214 85,643 54,325 222,182

Average Day Load Wastewater Temperature = 10°C

Mixing2 21,444 30,634 30,634 82,712

Average 52,366 60,749 38,337 151,452

Peak 67,270 83,695 53,089 204,054

Max Day Load Wastewater Temperature = 20°C

Mixing2 21,444 30,634 30,634 82,712

Average 90,264 74,937 46,059 211,260

Peak 108,721 102,827 54,148 265,696

Max Day Load Wastewater Temperature = 10°C

Mixing2 21,444 30,634 30,634 82,712

Average 66,753 74,705 53,473 194,931

Peak 80,344 89,195 70,012 239,551 Note: 1. Values provided at standard conditions (101.325 KPA, 15.6 °C, 0% Relative Humidity) 0.61 L air /m2/s - MOE Design Guidelines (Table 12-2) – aeration required for mixing (uniform MLSS)


Table 81 presents Preliminary Design specifications for the new Plant 3 and Plant 4 blowers.



Table 81 Preliminary Design Specification for the Plant 3 and Plant 4 Blowers Process Area Item Specification

Number of Blowers Six (6) Duty, One (1) Standby

Type High Speed Turbo – Single Stage Centrifugal

Capacity (air flow rate each blower) 7790 sm3/hr (4,588 SCFM, 186,960 sm3/day) 1

Input Power (each) 200 kW (268 HP)

Pressure 69 kPa (10 psi)

Aeration

Avg. AOR2 (kg/hr) 1110

Peak AOR2 (kg/hr) 1714

AOR2/SOR3 0.39 Note: 1. Values provided at standard conditions (101.325 KPA, 15.6 0C, 0% Relative Humidity) 2. AOR = Actual Oxygen Requirement 3. SOR = Standard Oxygen Requirement

Table 82 provides Preliminary Design specifications for the fine bubble membrane diffuser system diffusers. The same diffuser density has been assumed for each grid in each pass; the diffuser density will be refined during detailed design to divide each pass into two (2) or more zones with different diffuser densities for a more tapered configuration. For each pass, the average, maximum loading condition as well as the minimum aeration requirement for mixing was evaluated. The maximum of these conditions governed the diffuser density for each zone. The air flow control valves will provide flexibility to adjust air flow to each zone based on oxygen demands. Table 82 Preliminary Design Specification for the Plant 3 and Plant 4 Fine Bubble Diffusers

Parameter Pass 1 Pass 2 Pass 3

Diffuser Air Rate (m3/hr/Diff) 2.1 2.2 2.2

Pressure at top of drop leg (kPa) 60.4 60.2 60.0

SOTE (%) 38 37 36

No. of Diffusers per pass (per tank) 1320 1260 882

Dropleg Size (mm) 150 150 150

No. of Grids per tank 2 3 3


The new blowers will be equipped with VFDs to control blower output to match air demands. Each blower will communicate directly to a master control panel (MCP), which receives signals from process control variables, such as dissolved oxygen (DO) within the aerobic zone, with the system and sequences the blowers to operate at their most efficient design points. DO analyzers are installed in the aerated zone of each pass of each aeration tank. An air flow meter is provided for each pass of each aeration tank. The control objective of the process air control system is to provide communication among blower equipment, air flow control valves, air flow meters and DO probes via the blower MCP and to operate blowers and control valves in such a way as to provide the required oxygen at the lowest energy consumption. During normal operation, the control system will aim to maintain the DO concentration at a constant, operator selected set point in the aeration tanks by controlling the blowers and air flow control valves. The reading from a DO probe in a specific tank/pass will be transmitted to the blower MCP and compared to the DO set point. The air header flow butterfly control valves will modulate automatically to allow the required airflow to the tanks. The modulation of the valves results in a change in pressure in the air pipes, which is communicated to the blower MCP. The MCP adjusts the blowers’ output to maintain the target pressure. To maximize efficiency, the blowers will be operated in such a way as to minimize the need to throttle valves.



13.2.4 Plant 3 and 4 Aeration Tank Unwatering System


Aeration tanks will require periodic complete unwatering in order to perform maintenance services, such as tank and diffuser repairs. A portable submersible type unwatering pump will be provided in Plants 3 and 4. Discharge pipes will be installed at the end of Pass 3 of each aeration tank to allow the connection to the portable unwatering pump. In the event that an aeration tank is taken out of service, operators will connect the pump to its flexible hose and lower the pump into the sump from a portable gantry. Once the hose is connected to the fixed permanent pipe work, operators will operate the pump manually, discharging the drain to one (1) or more of the online aeration tanks in Plants 3 and 4.


Table 83 presents process design criteria for Aeration Tank Unwatering Pumps. Table 83 Design Criteria for the Aeration Tank Unwatering Pumps

Parameter Value

Aeration Tank Volume (m3) 10,462 Design Unwatering Time (hours) 48 Unwatering Pump Flow Rate ( m3/day/pump) 5,232


Table 84 presents Preliminary Design specifications for the new aeration tank unwatering pumps Table 84 Preliminary Design Specifications for the Aeration Tank Unwatering Pumps

Item Specification

Number of Pumps 1 Type Portable Submersible Capacity (each) 218 m3/hour TDH 8.5 m Power 1.7 kW (2.3 HP) VFD Required No


When an aeration tank needs to be taken out of service, the inlet gate and RAS gate of the offline aeration tank will be moved to their fully closed position. The unwatering pump will be connected to its flexible hose and lowered to the sump using a portable gantry. The hose will be plugged into the fixed permanent pipework to allow the operators to distribute the aeration contents to any of the other aeration lanes. One (1) portable submersible unwatering pump is provided to serve Plant 3 and Plant 4. A sump is provided at the end of Pass 3 of each aeration tank to allow the tank to be completely unwatered. The unwatering pump is sized to empty one (1) aeration tank over a 48 hour period. During unwatering, the WAS pumping rate will be increased to manage the solids concentration in the aeration tank that is receiving the additional mixed liquor.



13.2.5 Plant 3 and 4 Secondary Clarifiers


The secondary clarifiers provide separation of solids from treated effluent as well as thickening of MLSS for return to the aeration tank. Eight circular secondary clarifiers will be constructed to provide activated sludge settling and withdrawal for Plant 3 and Plant 4. Aeration Tanks 3-1 and 3-2 will discharge to Secondary Clarifiers 3-1 to 3-4 and Aeration Tanks 4-1 and 4-2 will discharge to Secondary Clarifier 4-1 to 4-4. The secondary clarification systems for each of Plant 3 and Plant 4 will consist of: One (1) secondary clarifier splitting chamber – evenly distributes mixed liquor among four secondary clarifiers. In

the event that a secondary clarifier is taken out of service, weir gates are provided at the splitting chamber to isolate that clarifier

Energy dissipating inlet – dissipates energy at the centre inlet of the clarifier to minimize currents within the secondary clarifier

Submerged flocculation baffle – creates flocculation zone in secondary clarifier Sludge collection mechanism – directs settled sludge to the hopper at the centre of each secondary clarifier for

withdrawal from the tank Hopper with underflow piping routed from the sludge collection hopper to the associated RAS/WAS pumping

station Scum collection skimmer – removes scum from the surface of the clarifiers and directs scum to scum chamber Effluent launder – collects clarified effluent and removes effluent from the secondary clarifier Stamford baffle – prevents solids carry over into effluent Cover on effluent launder to minimize algae growth and its impact to tertiary treatment

Settled activated sludge will be conveyed to secondary sludge hoppers at the centre of each clarifier using a “true” spiral full bridge type sludge scraper. The activated sludge will be continuously pumped from the hoppers and returned to the aeration tanks as RAS using individual suction lines from each secondary clarifier. WAS is withdrawn from each RAS suction line and pumped to the Thickening Building for further processing. Alternatively, the WAS can be transferred to the primary clarifiers for co-thickening. The RAS/WAS pumping system is described in detail in Section 13.2.8. Secondary scum accumulates on the surface of secondary clarifiers. Scum will be skimmed into a secondary scum chamber and subsequently pumped to the discharge of the WAS pumps to be transferred to the primary clarifiers.


Table 85 presents design criteria for the Plant 3 and Plant 4 secondary clarifiers.



Table 85 Design Criteria for the Plant 3 and Plant 4 Secondary Clarifiers Parameter Value

Average Flow Rate (MLD) 82

Peak Hourly Flow Rate (MLD) 206

Peak Instantaneous Flow Rate (MLD) 288

Design Max RAS Rate (% of Average Sewage Flow Rate) 100%

Design MLSS (mg/l) 3500

Maximum Surface Overflow Rate1 (m3/m2/day) 37

Maximum Solids Loading Rate2 (kg/m2/day) 170

Maximum Weir Loading Rate3 (m3/m/day) 375 Note: 1. MOE Design Guidelines Table 13.1 - based on design peak hourly flow (based on influent flow only) 2. MOE Design Guidelines Table 13.2 - Loading based on Peak Daily Flow 3. MOE Design Guidelines Table 13.1 – design peak daily flow plus the design max return sludge flow rate and design MLSS)


Table 86 presents preliminary design specifications for the Plant 3 and 4 secondary clarifiers. Table 86 Preliminary Design Specification for the Plant 3 and 4 Secondary Clarifiers

Parameter Specification

No. Units 8

Average Flow per Clarifier (MLD) 10.3

Peak Hourly Flow Per Clarifier (MLD) 25.7

Peak Hourly Flow Per Clarifier with one unit out of service (MLD) 29.4

Peak Instantaneous Flow Per Clarifier (MLD) 36.1

Clarifier Diameter (m) 31

Side Wall Depth (m) 4.6

Bottom Slope 12%

Surface Overflow Rate

at Average Day (m3/m2/day) 13.6

at Peak Day (m3/m2/day) 27.2

Solids Loading Rate

at Average Day (kg/m2/day) 95.3

at Peak Day (kg/m2/day) 167

Sludge Collection Mechanism Type Spiral Type Circular

Number of Mechanisms 8 (one per clarifier)

Drive 4 HP, 575 V/3Ph/60hz

Mechanism Dimensions 31 m (diameter), 4.65 m (depth)


Mixed liquor from Aeration Tanks 3-1 and 3-2 will be directed by gravity to Secondary Clarifier Splitting Chamber 3, where flow is equally split between Secondary Clarifiers 3-1 to 3-4, while mixed liquor from Aeration Tanks 4-1 and 4-2 will be directed by gravity to Secondary Clarifier Splitting Chamber 4, where flow will be equally split between Secondary Clarifiers 4-1 to 4-4. Flow will enter the secondary clarifier through a centre pipe and be distributed via a feed well to minimize currents. Solids settle to the bottom of the secondary clarifier and will be directed to a sludge hopper at the centre of the clarifier by a constantly rotating sludge collection mechanism. Settled activated sludge will be withdrawn from the tank by the RAS pumps. Secondary effluent will flow over a peripheral weir and the effluent launder will carry effluent out of the secondary clarifier and to the secondary effluent channel to tertiary



filtration. A Stamford Baffle, around the periphery of the effluent lauder, is provided to minimize solids carry over into the effluent. A skimmer will be provided to remove scum from the surface of the secondary clarifier. Scum will be directed to a scum collection chamber and pumped to the WAS pump discharge line to be transported to the primary clarifiers. The effluent water supply lines are connected to the scum collection chambers for water flushing when required. There are also effluent hydrants near the aeration tanks and secondary clarifiers; locations will be determined in detailed design.

13.2.6 Plant 3 and 4 Secondary Clarifier Unwatering System


Secondary clarifier unwatering is a manual task. Each tank will have a corresponding routing valve that is normally closed and opened when the tank is taken out of service. The RAS pump associated with the secondary clarifier will typically be used to unwater the tank to the extent possible after which a portable pump will be required.


Table 87 presents process design criteria for the secondary clarifier unwatering system. Table 87 Design Criteria for the Secondary Clarifier Unwatering System

Parameter Value

Secondary Clarifier Tank Volume (m3) 3,925

Design Unwatering Time (hours) 12

Unwatering Flow Rate ( m3/hr) 327


RAS pumps will be used for secondary clarifier unwatering. The Preliminary Design specifications for the RAS pumps are presented in Section 13.2.8.4.


In the event that a secondary clarifier is taken out of service, the inlet gate to that secondary clarifier at the respective secondary clarifier distribution chamber will be closed. The secondary clarifier will be emptied using its assigned RAS pump. While the clarifier is down, the flow will be directed to the remaining three (3) clarifiers by the distribution chamber. RAS and WAS pumping will be increased accordingly. If the stop log is removed from the aeration tank effluent channel, the aeration tank effluent flow is proportioned to the seven online clarifiers.

13.2.7 Plant 3 and 4 Secondary Clarifier Scum Pumping System


The secondary scum pumping system pumps accumulated scum skimmed off the secondary clarifiers and the aeration tank effluent channels. Scum will be directed to a scum collection chamber where it will be pumped by a fixed speed submersible pump. Scum will be pumped intermittently from the sump based on the level of scum in the chamber. Scum will be pumped to the WAS pump common discharge pipeline on the discharge side of the WAS pumps, where it directed to the primary clarifiers.


Table 88 presents process design criteria for scum pumping system.



Table 88 Design Criteria for the Scum Pumping System Parameter Value

Scum Collection Chamber Volume (m3) 30

Design Scum Pumping Time (hour) 1

Scum Pumping Flow Rate ( m3/hr) 30


Table 89 presents Preliminary Design specifications for the scum pumping system. Table 89 Preliminary Design Specifications for the Scum Pumping System

Item Specification

Number of Pumps 2 (1 per Plant)

Type Submersible

Capacity (each) 30 m3/hour

TDH 10 m

Power TBD

VFD Required No


One (1) submersible scum pump will be provided to serve one (1) aeration tank effluent channel and four (4) secondary clarifiers. As the scum fills the tank, the pump will operate intermittently to transfer the scum to the primary clarifiers via the WAS discharge line. This intermittent operation will be controlled by a timer that can be adjusted for interval between cycle and its duration. The timer will be overridden if the scum level in the scum collection chamber reaches the maximum set-point and the tank draining cycle begins. The scum will be pumped intermittently from the collection chamber based on its liquid level and the level set points entered by the operator. As the scum liquid level in the collection chamber reaches the “Pump Start Level”, the duty pump will start automatically to transfer the scum out of the chamber. The pump will stop when the scum level reduces to the “Pump Stop Level”. If the pump fails to turn on/off, an alarm will be issued. The scum level in the collection chamber will be monitored via a level transmitter.

13.2.8 RAS/WAS Pumping


The Kitchener WWTP will consist of three (3) activated sludge plants, each having four (4) secondary clarifiers: Plant 2, 3 and 4. A dedicated RAS/WAS pumping station will be assigned to each plant. The three (3) pumping stations share a similar design: each contains one (1) RAS pump per secondary clarifier and one (1) common standby RAS pump shared by each pair of clarifiers, and two (2) WAS pumps (1 duty, 1 standby) per set of four (4) clarifiers. The Plant 3 and 4 RAS/WAS pumping stations will be located adjacent to the effluent end of the aeration tanks, to provide common wall construction and interconnected for tunnel access. Each RAS/WAS pumping station will have a firm RAS pumping capacity of 33% of the total Kitchener WWTP design average day flow of 122,800 m3/d. RAS will be transferred from the secondary clarifiers to each plant’s aeration tanks while WAS will be transferred to the Thickening Building and/or the primary clarifiers (for co-thickening). The flow for both RAS and WAS pumps will be controlled through the SCADA system by adjusting the pumps’ VFDs.



The Plant 2 pumping station will consist of a new structure located on the site of the existing RAS/WAS screw pumping station. The new pumping station will house six (6) new centrifugal RAS pumps (4 duty, 2 standby) and two (2) new centrifugal WAS pumps (1 duty, 1 standby). The existing Plant 2 RAS/WAS screw pumping station will be demolished. Each of the three (3) new pumping stations will be of similar design and operation. A simplified plan view schematic of the RAS/WAS pumping station design used in the Kitchener WWTP upgrades is presented in Figure 23.

Figure 23 Simplified Plan View Schematic of the Kitchener WWTP Upgrades RAS/WAS Pumping

Station Design

The RAS from each secondary clarifier will enter its associated pumping station through dedicated suction lines; the RAS suction lines have been sized to carry the higher flow rates that will result when one (1) secondary clarifier is taken out of service. All RAS suction lines are connected by a common suction header; automated motorized knife gate valves located between the RAS pumps on the common suction header are normally kept closed, directing flow from a secondary clarifier to a dedicated RAS pump. One (1) standby RAS pump will be assigned to each pair of clarifiers; when a duty pump fails, the duty pump will be taken off line and the appropriate valve on the suction header will open to direct flow to the standby RAS pump; this procedure will occur automatically through SCADA. RAS will be discharged to the aeration tanks associated with the respective pumping station. The RAS discharge lines of the Plant 3 and 4 pumping stations will be interconnected to allow for some transferring of RAS between the two (2) plants under special circumstances (e.g., one aeration tank offline but all secondary clarifiers online), as described in Section 13.2.8.5.1.



WAS will be drawn from each secondary clarifier RAS suction line and enter a dedicated WAS suction header. The WAS pipelines from each secondary clarifier RAS suction line will each be equipped with a V-notch knife gate valve, which will be adjusted to balance the WAS flow from all clarifiers, and a check valve, which will prevent the development of a hydraulic connection between the clarifiers. The suction lines from each WAS pump will draw off of the common WAS suction header. WAS from all three (3) pumping stations is discharged to the WAS holding tanks or primary clarifiers through separate common discharge lines.

13.2.8.2 Plant 2 Existing Facilities

The existing Plant 2 RAS/WAS pumping station is a two (2) storey enclosed structure that houses two (2) inclined Archimedes screw pumps that draw sludge from a RAS/WAS wet well. RAS is returned to the head of the aeration tanks, while WAS is wasted to the primary clarifiers for co-thickening. WAS wasting is controlled by a manually operated valve on the RAS discharge header. Also, thicker WAS is drawn off from a hopper located at the center of each of the four secondary clarifiers to a common WAS chamber located adjacent to the clarifier inlet distribution chamber. From this common WAS chamber, WAS is pumped via submersible pumps to the primary clarifiers. Based on overall building condition and given that almost all process and HVAC equipment are past their life expectancy, the existing RAS/WAS pump station for Plant 2 will be decommissioned and demolished following the commissioning of Plant 3. The new pumping station will allow for improved control of RAS and WAS flow from each secondary clarifier to optimize performance. Existing RAS piping will be reused where possible.


The design criteria for the Plant 2, 3, and 4 RAS and WAS pumps that have been used as a basis for the development of the Preliminary Design are presented in Table 90. Table 90 Design Criteria for RAS and WAS Pumps

Parameter Value

RAS Flow per pumping station (m3/day)1 (total pumping capacity) Minimum 28,653 Average 40,933 Maximum 54,578

Design MLSS Concentration (mg/l) 3,500 RAS/WAS TSS Concentration (mg/l)

Minimum 5,000 Average 7,000 Maximum 10,000

Aeration Tank SRT (days) Minimum 8 Maximum 11

WAS Flow per pumping station2 (m3/d) (total pumping capacity)3 Minimum 666 Average 1,129 Maximum 1,831

Note: 1. Each pumping station is designed to accommodate 1/3 of total Kitchener WWTP design influent flow; minimum and average RAS flow based on 70%

and 100% of plant flow, respectively, and maximum RAS flow based on one (1) clarifier taken out of service at average flow 2. Based on minimum, average, and maximum WAS flow rates calculated using ranges of RAS/WAS TSS concentration (ranging from 5,000 to 10,000

mg/L) and Aeration Tank SRT (ranging from 8 to 11 days)




The preliminary design specifications for the RAS and WAS pumps are presented in Table 91 and Table 92, respectively. Table 91 Preliminary Design Specifications for RAS Pumps

Item Preliminary Design Specification for RAS Pumps Type Screw Centrifugal No. of Pumps 2 duty, 1 standby per pair of secondary clarifiers

Pump Capacity (each) (m3/d) Minimum1 7,163 Average2 10,233 Maximum3 13,644

Drive VFD Note: 1. Based on RAS rate of 70% of Plant 2 Average Day Flow 2. Based on RAS rate of 100% of Plant 2 Average Day Flow 3. Based on RAS rate of 100% with one clarifier out of service Table 92 Preliminary Design Specifications for WAS Pumps

Item Preliminary Design Specification for WAS Pumps Type Screw Centrifugal No. of Pumps 1 duty, 1 standby per group of four secondary clarifiers

Pump Capacity (each) (m3/d) Minimum1 666 Average2 1,129 Maximum3 1,831

Drive VFD Note: 1. Based on minimum WAS flow rate 2. Based on average WAS flow rate 3. Based on maximum WAS flow rate


13.2.8.5.1 RAS Pumping

The majority of secondary clarifier underflow will be returned to the aeration tanks as RAS. The control objective of RAS pumping is to return activated sludge to the aeration tanks and control the sludge blanket level in the secondary clarifiers by speed adjustment of duty pumps. Under normal operations, the RAS pumps will operate automatically, with the flow rate controlled by pump motor speed adjustments. These adjustments will be accomplished by the SCADA system based on pre-selected set points entered by the plant operators, depending on the preferred operating mode (i.e., ratio flow control based on plant influent flow or constant flow control). It will also be possible to use the RAS pumps in secondary clarifier unwatering. The Plant 3 and 4 RAS pumps will discharge to their specified aeration tanks through separate discharge headers. A connection has been provided between the Plant 3 and 4 discharge headers to provide additional operational flexibility when an aeration tank is taken out of service. A portion of the RAS from the plant with only one (1) aeration tank in service will be transferred to the plant with both aeration tanks in service. Therefore, the RAS flow will be increased to each of the remaining three (3) aeration tanks by approximately one third (at 100% RAS rate) to



compensate for the one (1) offline tank. This flow split will be achieved by manual adjustment of the valves on the RAS metered discharge header connection line and the RAS discharge line of the plant with the offline aeration tank.

13.2.8.5.2 WAS Pumping

A portion of the secondary clarifier underflow will be taken out of the secondary treatment process and wasted as WAS, which will be transferred to the WAS holding tanks, where it will be stored prior to thickening, or to the primary clarifiers for co-thickening. The control objective of WAS pumping is to waste excess activated sludge from the secondary treatment process and control the amount of WAS directed to the WAS Thickening Building or primary clarifiers by speed adjustment of duty pumps and flow measurement. Under normal operations, WAS pumps will be operated automatically by the SCADA system based on pre-determined set points entered by plant operators. These set points are based on aeration system control parameters such as SRT and MLSS concentration. WAS will be pumped from the WAS suction lines to the WAS holding tanks or to the primary clarifiers, and leave each pumping station in separate force mains. The operator can direct all flow to the desired destination through automatic adjustment of the motorized valves on the WAS holding tank and primary clarifier force mains. The two (2) force mains leaving each pumping station will join those from the other two (2) pumping stations and the combined flow to the WAS holding tanks and the primary clarifiers will be discharged in separate common discharge lines. The use of two (2) separate force mains allows for improved operational flexibility and redundancy. The two (2) force mains are joined by an interconnecting pipe within the pumping stations; the operator can manually adjust a V-notch knife gate valve on this interconnecting pipe to send a portion of WAS flow to both destinations.


13.3.1 Plant 3 and 4 Aeration Tanks and Secondary Clarifiers

The aeration tanks and secondary clarifiers are both to be built in the location of the existing lagoons. These lagoons will be decommissioned and cleaned prior to construction of the new tanks. Once the lagoon area is cleaned the expected elevation of the area is approximately 277.0 m, which is much lower than the remainder of the plant. To facilitate site drainage and connection to existing roads the lagoon area will have to be backfilled for the entire area of the lagoon to an approximate elevation of 281.52 m. The aeration tanks, secondary clarifiers, and associated chambers will be constructed from cast in place concrete. These structures will be designed for a design flood level of 282.37. The design for flood protects the structures from inflow of flood level by providing a minimum of 300 mm free board above the flood level. The design also protects the structures from flotation by providing hold down soil anchors. The access to the tanks will be supplied by stairs from grade up to the top of the tanks. Access across the aeration tanks will be provided on the inlet and outlet chambers and two (2) longitudinal catwalks and one (1) transverse catwalk across the tank. All the valves, flow meters, mixers and DO probes will be accessible from these walkways.

13.3.2 Plant 2, 3 and 4 RAS/WAS Pumping Stations

The Plant 2 RAS/WAS pumping station will be an independent structure located on the site of the existing pumping station. The station will be set at an elevation that allows gravity flow from the secondary clarifiers into the station. The new Plant 3 and 4 pumping stations will be located adjacent to the Plant 3 and 4 aeration tanks, in between the aeration tanks and the secondary clarifiers. The pumping station foundations will be set at the same elevation as the base of the aeration tanks, and protected from floatation by soil anchors. The two (2) pumping stations will be connected by a fire separated tunnel that will run between the pumping stations.



Each pumping station will contain a pumping room mostly below grade with two (2) exit/access stairs to the roof of the building. The roof of the building will support an electrical room, HVAC equipment and an access hatch for servicing equipment. The roof elevation will be above design flood level, preventing flood waters from either entering the station or damaging the equipment. Access to the roof of the structure will be supplied by way of stairs. The buildings will be a cast in place water tight structure below grade housing the pump room. The above grade access houses for the stairs and electrical rooms will be built of load bearing concrete block with a precast roof structure. The interior of the pump rooms will be exposed concrete, and the above grade electrical rooms will feature walls and ceilings finished with epoxy coatings, and the floor will be will be finished with a protective non slip epoxy coating. The architecture of the pumping stations will reflect the vision for all new buildings on the site, using a combination of local cultured stone, metal siding or aluminum composite panels for the exposed surfaces above grade. The exterior cladding will both tie the structure into the rest of the plant and provide insulation to protect the structure. Using similar building materials throughout allows for economies of scale, ease of maintenance and cost efficiencies. While LEED is not a requirement for this facility, sustainable ideas such as the use of locally harvested and manufactured materials and a white roof will be incorporated into the design.



Indoor design conditions are summarized in Table 93. Table 93 Indoor Design Criteria for Plant 3 and 4 Secondary Treatment and Plant 2 RAS/WAS Pumping

Station Areas Criteria

Electrical Rooms 24 °C (summer) 50% RH / 22 °C (winter)

Pump Rooms 5~10 °C unoccupied mode and 18 °C for occupied mode (winter) / 5.5 °C above outdoor temperature (summer)


Because ventilation rates are mandated by NFPA 820, a significant heating load is anticipated for the new pumping stations. Gas fired unit heaters will provide supplementary heat for the pumping area. Electric unit heaters and baseboard heaters will provide heating for the electrical room and stairs. A preliminary heating load analysis shows that the max heating load for building will be approximately 250,000 Btu/h range for each pumping station. It is assumed that natural gas is available and will be used as a heating source.

13.4.1.2 Ventilation

The ventilation rates for the various secondary treatment areas are summarized in Table 94.



Table 94 Ventilation Rates for Plant 3 and 4 Secondary Treatment and Plant 2 RAS/WAS Pumping Station

Location and Function NFPA 820 Table and Row

NFPA Classification

NFPA Ventilation Rate

Ventilation Rate and Additional Notes

New Pump Room Basement Table 6.2(a), Row 9, Line B Unclassified Continuous ventilation at 6 ACH 6 ACH

New Electrical Room/Control Room N/A Unclassified N/A Air conditioning unit

The RAS/WAS Pumping Station pump room areas will be provided with HVAC systems consisting of one (1) gas fired AHU (AHU-2 for Plant 2, AHU-3 for Plant 3, and AHU-4 for Plant 4) for each pumping room incorporating two (2) supply and two (2) exhaust fans, each fan with 100% of the required flow rate.


The electrical rooms located on the roof of each pumping station will be serviced by ceiling mounted indoor AC units (one in each electrical room) to prevent electrical equipment from overheating.



A potable water connection and tankless hot water heater will be supplied to the sampling sink in each pumping station. Low water use plumbing fixtures and trim will be specified, and cross-connection control will be provided, in accordance with requirements of the OBC. Potable water will be metered at the building.






A floor drain system, consisting of 4 floor drains and associated piping, will be provided in each of the RAS/WAS pumping stations. The floor drains will drain by gravity to the sanitary sump.


One (1) sanitary sump, equipped with duplex submersible pumps, is provided in the lower level of each pumping station. The sanitary sump pumps will pump into the nearest sanitary sewer or into the aeration effluent channel.


One (1) safety eyewash unit will be provided outside, above the tunnel which connects Plant 3 and 4 RAS/WAS pumping stations. The unit will be provided with tempered water from emergency mixing valves and will be provided with a flow switch, light, and alarm bell. The alarm device will be the manufacturer’s standard unit and will to be coordinated with electrical for power requirements. The combination eyewash unit located outside of the building will be a freeze-resistant unit.


The electrical design of the secondary treatment system is presented in detail in Section 17.









14. Administration Building (Contract 5a) 14.1 General Description

Administration Building drawings (Series 600) are contained in Appendix A.

14.2 Architectural Design

The new administration building will be located at the front of the property across from the main site entrance. It will be front and centre at the base of the hill and a clear destination to all visitors. Its location will help to control site access and prevent visitors from having to travel through the entire site as is currently the norm. The new location will make the new administration building more visually and physically accessible and locate it in the heart of the planned upgrades. The new administration building will be designed in accordance with sustainable practices with the goal of achieving the LEED Silver designation. The construction of the building will include renewable and sustainable resources such as cast-in-place concrete, natural stone, precast concrete, and steel. The building will incorporate other elements of green building design, such as energy and water efficiency and indoor environmental quality. The architectural façade of the facility will incorporate local natural materials such as limestone selected from local quarries and exterior wood panels from sustainable forests. The appearance of the building will harmonize with the surroundings and complement the addition of the new headworks, thickening and tertiary treatment buildings to create a unified architecture on the site. The interior will make use of durable low maintenance finishes such as fibre rock abuse resistant gypsum panels for the walls which have 95 percent recycled content and porcelain tiles for the floors for durability and ease of cleaning. The two (2) storey 1,775 m2 administration building will serve as the nerve centre for the plant, accommodating operations, technical and support staff. The building will be orientated on the site to take advantage of natural day-lighting, sun orientation, wind protection and views. Of primary importance in the design will be the views from the west facing second story control room, which is required to overlook the entire plant. The ground floor of the building will house the site reception, laboratory, training room, men’s and women’s washroom/change room facilities, offices and the mechanical room. The second floor level will include the control room, SCADA room, meeting room, lunch room, offices, library/archive room, and washroom. The two (2) storeys of the building will provide a vertical separation for the Region and OCWA while providing better visual access to the WWTP from the control room.

14.3 Existing Administration Building Description

The existing administration and maintenance building is a single storey structure that is located to the west at the rear of the site. The building consist of Region and OCWA offices, change rooms, training room, laboratory, SCADA room, pump room and a maintenance workshop and garage. Due to the growing needs of the Region and OCWA, the facility has outgrown its use as a place for administration. The building will be dedicated for the purposes of maintenance and become a maintenance hub for the Region. A renovation and modest addition will allow for the accommodation of additional workshops, storage and offices dedicated for the purposes of maintenance. The current building sits upon poor soil conditions which necessitated the use of caissons and grade beams when the 2004 addition was built. It is likely this same method of construction will be required for the expansion.



The SCADA room will be maintained within the existing facility until the new administration building is completed at which time it would be transferred to the new facility.

14.4 LEED Concepts

The desire to pursue LEED Silver certification for the new administration facility will encourage the building design to be respectful of the plant’s surroundings and provide a finished product that is energy efficient, durable, flexible and unique. Through an integrated design process, there will be opportunities to incorporate ideas such as green roofs, passive and solar energy generation, natural day-lighting, storm water reuse and recycling, and local and durable materials into the project. The building orientation will be established to best utilize the surrounding environmental conditions and site layout features. Each elevation will be designed differently to enhance sightlines, promote natural day-lighting within the building, and maximize efficient operation of building services. The building services become more efficient by enhancing natural daylight and limiting negative environmental exposure effects from the wind, sun orientation and seasonal temperature changes. The building will make use of operable windows allowing for natural cooling during the summer months. The building will also incorporate sun shades and light shelves on the south and west elevations. Sun shades limit heat gain and glare from the high sun during the summer months while at the same time permitting the low lying winter sun to enter. Light shelves are used to reflect natural daylight further into the building and limit the need for artificial lighting throughout most of the day. The intent is for the design of the administration building to incorporate several energy efficient technologies which may include geothermal heating and cooling, solar panels, collection and reuse of rainwater, and natural day lighting. Please refer to the Preliminary LEED Scorecard in Appendix N.



Heating, ventilating and AC to the administration building will be provided by means of a combination of water source heat pumps located throughout the building and a closed circuit cooling tower and a pair of natural gas fired condensing water heaters. The systems will be designed to maintain the interior environment between 22ºC (72ºF) to 26ºC (78ºF) and 40% to 50% relative humidity during occupied hours. Ventilation air will be provided through a natural gas fired, DX cooling packaged rooftop unit complete with an energy recovery enthalpy heat exchanger. Ventilation requirements will be in accordance with ASHRAE 62 – Standard for Indoor Air Quality and will be a minimum of 2.5 lps (5.0 cfm) per person and 0.3 lps·m2 (0.06 cfm·ft2). The system will also include demand control ventilation by incorporating carbon dioxide and occupancy sensors in each climate zones.



A new combination potable and fire water service shall be provided to the new facility and will be connected to the existing site infrastructure. Inside the mechanical room the combination service shall be split into a potable water and fire suppression service. Each service shall be individually valved complete with reduced pressure principle



backflow preventers. A new water meter will be provided for the facility on the potable water service. A water softener will be provided to condition the potable water and hydronic system make-up water. Domestic hot water for the facility will be provided by a new natural gas fired instantaneous water heater(s) located in the mechanical room. Domestic hot water shall be heated to 60ºC (140ºF) and distributed to the plumbing fixtures throughout the facility. Lavatories shall include a thermostatic mixing valve to reduce the domestic hot water delivery temperature to 43ºC (110ºF). Emergency fixtures will also include a thermostatic mixing valve to reduce the domestic hot water delivery temperature to 27ºC (80ºF) in accordance with ANSI requirements.


Not applicable.


Rainwater will be collected from the roof drains and weeping tiles. The collected water from the roof will be filtered and pumped to washroom flush valves and/or irrigation systems. The gray water cistern overflow and weeping tiles will be delivered to the underground storm drainage system.


Not applicable.

14.5.2.5 Sanitary System

Sanitary waste will be collected from each plumbing fixture and flow to a sanitary pumping station. The pumps will discharge, via forcemain, to the influent channel upstream of the screens in the Headworks Building. An acid neutralizer/dilution system will be provided for the laboratory. Sanitary venting will be provided in accordance with the OBC.

14.5.3 Fire Protection

Portable fire extinguishers will be provided in accordance with the OBC, the OFC and the National Fire Protection Association Standard No. 10.

A new automatic wet sprinkler system will be provided to serve the facility in accordance with the OBC, the National Fire Protection Association Standard No. 13 and the Owner’s Insurer’s requirements.



15. WAS Thickening (Contract 5b) 15.1 General Description

At present, co-thickened WAS and primary sludge are conveyed to the existing primary digesters. As part of the Phase 3 Kitchener WWTP upgrades, sludge thickening processes will be provided and housed in a new facility. The new Thickening Building will be constructed on the site of the abandoned digesters that were used as temporary sludge holding tanks, located south of the boiler building and east of the primary digesters. Initially, only WAS will be thickened prior to digestion; however, space will be reserved in the new Thickening Building for additional equipment to provide capacity for thickening primary sludge. Once the Thickening Building is brought online, primary sludge will be diverted to the Thickening Building and blended with thickened WAS (TWAS). Blended sludge (TWAS and primary sludge) will then be pumped to the primary digesters. The design conditions are summarized below: Condition 1 – Current Operation: Co-thickened sludge is pumped from the primary clarifiers to the primary

digester Condition 2 – WAS Thickening is Operational: WAS is pumped to the WAS equalization/holding tanks to

provide flow balancing for thickening. WAS is thickened using RDTs and conveyed to the thickened sludge holding tanks. Primary sludge is pumped from the primary clarifiers to the thickened sludge holding tanks. Blended sludge (TWAS and primary sludge) is pumped to the primary digester. Flexibility is provided to allow primary sludge to be pumped directly to the digesters rather than blending with TWAS.

Condition 3 – WAS and Primary Sludge Thickening are Operational: WAS is pumped to WAS holding tanks and primary sludge to primary sludge holding tank to await thickening. WAS and primary sludge are thickened in the RDTs and conveyed to the thickened sludge holding tanks. Blended sludge [TWAS and Thickened Primary Sludge (TPS)] is pumped to the Primary Digesters. Flexibility will be provided to allow TWAS and thickened primary sludge to be pumped to the digesters separately.

WAS from Plants 2, 3 and 4 will be pumped to new WAS holding tanks, located below grade in the Thickening Building. RDTs will be installed for WAS thickening. Dedicated pumps will pump WAS from the WAS holding tanks to the flocculation tank upstream of the RDTs. Polymer will be injected in-line to facilitate flocculation and thickening. Thickened sludge will flow by gravity to thickened sludge holding tanks below. Primary sludge (un-thickened) and TWAS will be pumped from their sludge tanks via a common header to feed the digesters. RDT filtrate will flow by gravity to a thickening filtrate tank below, and will be pumped back to the WWTP and discharged at the primary clarifier effluent channel. To improve cost-effectiveness, dry polymer will be used as the main system; however, an alternate emulsion polymer system, comprised of emulsion polymer totes (a tank if required) and feed pumps, will also be provided. WAS and primary sludge holding tanks and pumps are provided in the basement of the Thickening Building for interim sludge storage, equalization and feeding to RDTs. WAS and thickening filtrate holding tanks will be equipped with submersible mixers, and TWAS holding tanks will be equipped with jet mixing nozzles and pumps, to prevent settling. Pumps will be equipped with VFDs for flow adjustment. All flows entering or leaving the Thickening Building will be metered. A simplified process flow schematic of the WAS thickening system is presented in Figure 24.



Figure 24 Simplified Process Flow Schematic of the Liquid Train of the WAS Thickening System

The Kitchener WWTP is being upgraded to provide treatment capacity for the projected flow in year 2041. Ultimately the Thickening Building is to provide capacity for peak month sludge generation rate of 55,547 kg/d, including 26,232 kg/d of primary sludge and 29,315 kg/d of WAS. However, as part of the current upgrades, only WAS thickening equipment will be installed with provisions for future equipment. The following key features will be incorporated in the new Thickening Building: New WAS holding tanks, equipped with submersible mixers, and WAS feed pumps to RDTs and a future primary

sludge holding tank and space for primary sludge feed pumps to RDTs Thickened Sludge Tanks, equipped with chopper pumps and jet mixing nozzle, and pumps Thickening Filtrate Tank, equipped with submersible mixer, and feed pumps RDTs with space for future primary sludge RDTs Dry polymer system, complete with make down system, feed/aging tanks and feed pumps Alternate emulsion polymer feed system Odour control system NFPA 820 compliance

The new Thickening Building will be constructed adjacent to the new energy centre. The one-storey building will house thickening equipment, polymer equipment, holding tanks and pumps, a dedicated control room and space for



polymer storage. A loading dock and roll up door will be provided for polymer delivery. Two (2) modular biofilter units, located to the south of the Thickening Building, will be installed for Thickening Building odour control. The preliminary footprint of the new building is approximately 36 m x 20 m. Process equipment such as RDTs, and polymer feed tanks will be located on the ground floor of the building, while the holding tanks, pumps and polymer pumps will be located in the basement level. The odour control biofilters will be located outside of the Thickening Building at grade level while related ancillaries will be located on a platform above the regional flood elevation of 283.63 m. The control room will be located on the ground floor, while HVAC units will be located on the roof of the building. The electrical room will be in the energy centre building adjacent to the Thickening Building. Due to the high flood water level at the site, all building entrances, including access to the first floor, will be situated above the regional flood elevation of 283.63 m. The new Thickening Building incorporates a new pilot plant room to facilitate treatability studies. Sludge thickening building drawings (Series 700) are contained in Appendix A. The preliminary process control narratives and process and mechanical equipment lists are presented in Appendix J and K, respectively.

15.2 Process Design

15.2.1 WAS Holding Tanks and Pumps


WAS will be pumped to the WAS holding tanks located in the basement level of the Thickening Building. Two (2) WAS holding tanks have been included in the design to provide operational/maintenance flexibility. The two (2) tanks are separated by a dividing wall, which is equipped with an isolation valve to allow for common or separate operation. The tank feed piping is such that the feed stream can be directed to either tank or divided between the two (2) tanks. The WAS holding tank overflow directs excess flow to the thickening filtrate tank. Each tank will be equipped with a submersible mixer to prevent solids from settling.


The design criteria of the WAS holding tanks is based on projected sludge production and quality presented in Table 21.


Table 95 summarizes the preliminary design specifications of the WAS holding tanks.



Table 95 Preliminary Design Specifications for WAS Holding Tanks Item Specification

WAS Holding Tanks

No. of tanks 2

Volume (useful), each 340 m3

Dimensions, each 8.75 m x 8.75 m x 4.25 m

WAS Holding Tank Mixers

No. of units 2 (1 each tank)

Type Submersible

Motor size 3 kW (each)

Drive CS

WAS Feed Pumps

No. of units 3

Type Non-clog centrifugal

Capacity at rated pressure 23 liter/sec @ 10 m

Motor size 7.5 kW

Drive VFD

15.2.1.4 Operating Philosophy, Instrumentation and Control

The control strategy of the WAS holding tanks and pumps is to equalize WAS flow rate and provide a constant feed of WAS to the RDTs. Monitoring points include: Level sensors to monitor WAS holding tanks levels Alternating high and low level switches to control pump operation Flow meters for feeding WAS to the RDTs Grab samples to monitor total solids concentrations of WAS fed to the RDTs

15.2.2 Rotary Drum Thickeners


For the new Thickening Building, space for a total of six (6) RDTs will be provided, however, only three (3) RDTs (2 duty, 1 standby) associated with WAS thickening will be installed. Under normal operating conditions, two (2) duty WAS RDTs will provide sufficient thickening capacity.


Table 96 presents the design criteria of the RDTs used as the basis for the development of Preliminary Design. A conservative WAS feed solids concentration of 9,500 mg/L was used.



Table 96 Design Criteria for RDTs Parameter Average Peak

WAS Feed Solids Concentration (mg/l) 7,000 10,000

TWAS Concentration 5 – 6%

Solids Recovery 90%

TWAS to Digestion (kg/day) 20,890 29,315

TWAS to Digestion (m3/day) 402 564

Thickening Filtrate Solids Load (kg/day) 2,338 3,288

Thickening Filtrate Flow (m3/day) 1,897 2,662 Note: 24 hours per day, 7 days per week operation


Table 97 presents the preliminary design specifications for the RDTs. Table 97 Preliminary Design Specification for RDTs

Parameter Specification

Number of RDTs 3 (2 duty, 1 standby)

WAS Feed Flow / RDT (average) 17 l/s

WAS Feed Load / RDT (peak) 23 l/s

Hydraulic loading rate with polymer (each) 17 - 23 l/s @ 0.7% solids

Polymer dose 11 kg/t (active)


Three (3) (2 duty, 1 standby) RDTs, located on the ground level of the Thickening Building, are provided for WAS thickening. RDT duty selection and WAS pumping rate will be based on providing a constant WAS feed to the RDTs. Monitoring points include: RDT and flocculation tank operation Flow meters for sludge feed and polymer feed

15.2.3 Thickening Filtrate Tank and Pumps


RDTs filtrate will flow by gravity to the thickening filtrate tank in the basement of the Thickening Building and will be pumped by two (2) (1 duty, 1 standby) centrifugal pumps to the primary clarifiers effluent flow splitting chamber.


Table 98 the design criteria of the thickening filtrate tank used as a basis for the Preliminary Design. Table 98 Design Criteria for Thickening Filtrate Tank

Parameter Average Peak

Thickening Filtrate Flow (m3/day)1 2,291 3,242 Note: 1. 24 hours per day, 7 days per week operation. These values include WAS and primary sludge thickening filtrate and polymer dilution water




Table 99 summarizes the preliminary design specifications for the thickening filtrate tank. Table 99 Preliminary Design Specification for Thickening Filtrate Tank

Item Specification

Filtrate Tank1

No. of Tanks 2

Volume (useful) 180 m3

Dimensions (Total- both tanks) 10.0 m x 4.0 m x 4.25 m

Filtrate Tank Mixer

No. of Units (each tank) 1

Type Submersible

Motor Size 2 kW

Drive CS

Filtrate Pumps

No. of Units 2 (1 duty, 1 standby)

Type Non-clog centrifugal

Capacity at TDH 38 liter/sec @ 15 m

Motor size 11 kW

Drive VFD Notes: 1. Provides 2 hour HRT at design condition 3


RDT filtrate will flow by gravity to the filtrate tank in the basement and pumped through a centrifugal thickening filtrate pump to the primary clarifier effluent flow splitting chamber downstream of the primary clarifiers. Each thickening filtrate pump will be equipped with a VFD to match pump output to thickening filtrate production. Monitoring points include: Level sensors to monitor thickening filtrate tank level High and low level switches to control pump operation Flow meter on the common discharge header to monitor thickening filtrate flow to the primary clarifier effluent

flow splitting chamber. Grab samples to monitor total solids concentrations of thickening filtrate discharged from the RDT

15.2.4 Thickened Sludge Holding Tanks and Pumps


TWAS flows by gravity from the RDTs to the two (2) thickened sludge holding tanks in the basement level of the Thickening Building, from which duty/standby positive displacement pumps transfer the blend of TWAS and un-thickened primary sludge to the anaerobic digesters for digestion. Two (2) thickened sludge holding tanks will be provided for improved operational/maintenance flexibility. The two (2) tanks will be divided by a wall that is equipped with an isolation valve for common or separate operation. The tank feed piping will allow the feed stream to be directed to either tank. Once the Thickening Building is brought online, primary sludge will be diverted to the Thickening Building and blended with TWAS. Blended sludge (TWAS and primary sludge) will then pumped to the primary digesters.



Jet mixing nozzles and sludge circulation piping will be provided to prevent solids settling in the thickened sludge holding tanks; the mixing will be carried out by chopper pump(s).


Table 100 summarizes the design criteria of the Thickened Sludge Holding Tanks used as a basis for the Preliminary Design. Table 100 Design Criteria for Thickened Sludge Holding Tank

Parameter Average Peak

TWAS Concentration 5 – 6%

TWAS to Digestion (kg/day) 20,890 29,315 TWAS to Digestion (m3/day) 402 564 Raw Sludge Flow at Average Raw Sewage TSS Load (3.1%) (m3/d) 604 846 Note: Assumes 24 hours per day, 7 days per week operation


Table 101 presents the key preliminary design specifications of the thickened sludge holding tanks. Table 101 Preliminary Design Specification for Thickened Sludge Holding Tank

Item Specification

TWAS Tank

Number of Tanks 2

Volume (useful) (each) 130 m3

Dimensions (each) 7.25 m x 4.0 m x 4.25 m

TWAS Tank Mixing System

No. of Pumps 2 (1 duty, 1 standby)

Type Chopper

Motor Size (each) 11 kW (each)

Drive CS

Number of Nozzles (each tank) 8

TWAS pumps

No. of Units 2

Type Positive Displacement

Capacity at TDH 25 liter/sec @ 350 rpm

Motor size 15 kW

Drive VFD


Two (2) thickened sludge progressive cavity pumps (1 duty, 1 standby) will be provided to transfer a blend of thickened WAS and unthickened primary sludge to the primary digesters. The pumps will be equipped with VFD motors for flexible control of pump output, thereby maintaining a relatively continuous feed to the digestion process. Monitoring points include: Level sensors to monitor thickened sludge tanks levels Alternating high and low level switches to control feed pump operation Flow meters to monitor thickened sludge feed to the digesters Grab samples to monitor total solids concentrations of thickened sludge discharged from the RDT



15.2.5 Polymer System


The new thickening polymer system will be installed on ground level of the Thickening Building and will incorporate a dry polymer system. Polymer injection and flocculation are critical to the performance of RDTs. For maximum operation flexibility, the dry polymer system will have the ability to accept emulsion polymer.


Table 102 summarizes the design criteria of the polymer system used as the basis for the Preliminary Design. Table 102 Design Criteria for WAS Thickening Polymer System

Parameter Value

Average polymer dosage rate (kg active polymer/tonnes dry solids) 10

Polymer dosage range (kg tonnes dry solids) 5 to 15

Average polymer requirement (kg/day) 209

Peak Polymer requirement (kg/day) 293

Storage requirement (based on average flow) (days) 15


Table 103 presents the preliminary design specifications of the thickening polymer system.



Table 103 Preliminary Design Specification for Thickening Polymer System Item Specification1

Dry Polymer Feed System

Dry Polymer Makedown system

No. of units 2

Capacity 14.2 kg/hr @ 0.5%

Dry Polymer Solution Tank (Wetting Chamber)

No. of units 2

Volume

Dry Polymer Solution Tank Mixer

No. of units 1 (each tank)

Type Top-mounted

Motor size 1 kW

Drive CS

Polymer Mix/Feed Tank

No. of units 4

Volume (each) 2,800 litre (working volume)

Tank Mixers (one per tank)

No. of Units 1 (each tank)

Type Top-mounted

Motor Size 1.5 kW

Drive CS

Polymer Feed Pumps

No. of Units 3


Capacity 1,636 LPH (27.3 L/min) per pump

Motor size 1 kW

Drive VFD

Dilution water requirements 31 l/min

Alternate Emulsion Polymer System

No. of Units 1


Duplex strainer 1

Pressure regulating valve 1

Dilution water requirements 62 l/min Note: 1. Sized based on dry polymer as the main source of polymer system.


The polymer system will automatically make-down polymer as required. Polymer will be added in-line at one of two (2) locations prior to the RDT flocculation tank. The polymer feed rate will be automatically flow paced to match the incoming WAS feed rate. Monitoring points include: Polymer feed pump operation Polymer make down system operation Flow meters to monitor the polymer feed to the RDTs



15.2.6 Hoisting System

One (1), two (2) tonne monorail and hoist will be provided in the ground floor of the Thickening Building over the RDT equipment and the opening to the level below. The purpose of the monorail is to facilitate lowering of equipment to the basement level and the lifting of RDT drums. Unloading of polymer bags from delivery trucks, and moving them from the polymer storage area and lifting them on to the polymer makedown assembly will be accomplished by a forklift to be provided for the Thickening Building.

15.2.7 Odour Control


The Thickening Building will be equipped with a new OCS, which will contain and treat odorous air. The OCS will treat odorous air from the following sources: Collection and treatment of air from RDT Collection and treatment of air from the holding tanks in the basement of the Thickening Building The OCS will be comprised of two (2) sub systems. The first subsystem will be the conveyance system which

comprises of ductwork and balancing dampers inside the Thickening Building. This network of ducts will convey the airflow to the second subsystem, the biofilter system.

The conveyance subsystem will contain the following equipment: One (1) lot of ductwork One (1) lot of balancing dampers Associated equipment such as expansion joints, supports, hangers etc.

The biofilter subsystem will consist of two (2) modular biofilters located on the south of the facility. The biofilter system will reduce odour contained within the foul process air by a minimum of 90%. The biofilter contains the following equipment: Two (2) independent modular biofilter systems Integral humidification system Two (2) duty and standby recycle pumps Sump freeze protection heater Two (2) duty and standby blower fans Media irrigation system.

Additional components required for the OCS are listed below: Biofilter foundation/slab Platform to support biofilter fans, ductwork and equipment cabinets above the regional flood line (283.63 m) New supports and foundations for odour control ductwork throughout new Thickening Building Electrical supply, lighting, heat tracing and lightening protection (on stack) Site services including plant effluent line and drainage lines Control wiring, RPUs and programming.


The areas designated for direct odour control will be isolated from the building general ventilation and include tank headspaces and equipment headspace. These areas are not meant to be occupied and do not require the same air exchanges as the building air. Therefore, the main objective of odour control is to maintain negative pressure inside



these areas and contain the odours. In general, the covered headspaces of channels, tanks and distribution areas are ventilated at between one (1) and three (3) ACH; this level of air movement within unoccupied spaces will provide a good balance of maintaining negative pressure and lowering building operating costs. The process equipment of primary concern in the Thickening Building are the RDTs. Odour control take-off points will be provided to maintain the equipment under negative pressure. Based on previous experience, equipment odour control take-offs should not be over-ventilated, to avoid extracting liquids and other debris into the odour control ductwork. Typical odour control points for equipment range from 50 to 200 L/s and larger units may have multiple collection points. Air flow rates from the collection locations are presented in Table 104. Table 104 Odour Control Airflow Rates

Area Ventilation Rate Air Flow Rate m3/h (cfm) RDTs 200 m3/h (113 cfm) per unit 1,000 (588)

Holding Tanks 3 ACH (50% full) 2,890 (1,701)

Subtotal 3,890 (2,290)

TOTAL 4,000 (2,353)

Due to the potential for organic sulphides and mercaptans in the odorous air, biofilters will be used for odour control. Two (2) parallel duty odour control units will be used to ensure that odorous air can continue to be managed during maintenance of a single unit.


Odourous air ductwork will be installed throughout the new Thickening Building. Each take-off point will be sized for the necessary flow rate and be equipped with a manual damper for balancing. Consideration will be given at each take-off point to ensure operator accessibility and ease for maintenance and repair. Table 105 provides preliminary design specifications for ductwork and accessories. Table 105 Preliminary Design Specifications for Ductwork and Accessories

Parameter Criteria

Velocity 5.1 to 15.2 m/s

Temperature 5 to 40 °C

Pressure 0 to -4.0 kPa

Material SS304/316 or FRP

Balancing Damper

Type Manual butterfly with hand operator, lockable

Leakage ~5%

Expansion Joints Typical, synthetic rubber

Table 106 provides design specifications for the odour control units.



Table 106 Preliminary Design Specifications for Odour Control Units Parameter Criteria

No. of Units 2

Capacity, each 2,500 m3/h

Type Inorganic Media, and biofilter

Media Volume 16.7 m3

Empty Bed Residence Time 20 s

Vessel Dimensions 3.66 m dia. by 3.66 m (H)

Overall Footprint 7.3 m (W) x 8.5 m (L)

Assumed Inlet Loadings

H2S 5 ppm (avg) / 15 ppm (peak)

Organic Sulphides <4 ppm (peak)

The biofilter system will be equipped with two (2) ID fans (1 duty, 1 standby). Each fan will be sized for a capacity of 5,000 m3/hr at 3.0 kPa static pressure. The corresponding motor size is 15 kW and will be equipped with a VFD to control the air flow through the system. Upstream and downstream motorized dampers for fan isolation will be provided for both fans. The fans will be located upstream of the biofilter. The MCCs and/or control panels can be located on the structural slab close to the equipment as required for the controllers and to simplify the package supply process. The MCC cabinets can also be contained inside the new Thickening Building or in a small pre-fabricated building to facilitate all-season operational and maintenance access. Table 107 provides preliminary design specifications for the odour control fans. Table 107 Preliminary Design Specifications for Odour Control Fans

Parameter Criteria

Flow Rate 5,000 m3/h

Static Pressure 3 kPa

Fan kW 12

Motor kW 15

Type Centrifugal or as required

VFD Yes, 2 separate


The biofilter will maintain a negative pressure draw on the headspace air within the influent sources listed in Table 104. Each foul air take-off point will be equipped with a manual balancing damper (initially balanced during commissioning). If an odour branch header cannot be provided with individual dampers at each outlet, a balancing damper will be provided for the entire branch. The biofilter will have two (2) modes of operation, manual and automatic. Normally the biofilter will be placed in automatic mode, where the fans and recirculation pumps are auto-alternated between duty and standby modes for system redundancy in case of required maintenance. The biofilter will be arranged as a two (2) module system to allow for continued odour treatment when one (1) of the two (2) modules requires maintenance. Actuated dampers on the inlet and outlet will provide isolation from process air in the closed biofilter modules. Under normal conditions, inlet and outlet isolation dampers at the biofilter modules will remain fully open. The biofilter PLC will be connected to the plant-wide SCADA network. There is no SCADA control of the biofilter system.



Pressure differentials across the depth of the media bed provide a means to evaluate the bed condition. When approaching 2 kPa of pressure loss across the media, an alarm will be triggered on the plant SCADA system to indicate that inspection or maintenance on the bed is required. Pressure across the media will increase as the media ages and biomass and elemental sulphur build-up within. At start-up the pressure loss will be below 0.5 kPa. Media bed temperature is also measured and an alarm will be triggered if the temperature reading in the bed becomes too low. Biofilter media irrigation is performed for thirty (30) minutes a day on each cell in both biofilters. Water flow is recorded by a flow indicator on the water inlet line. A timer connected to a solenoid valve in the biofilter control panel opens the valve for the specified amount of time each day to allow water to flow to the irrigation spray nozzles. Humidification is provided by an integral chamber with packing material and water recirculation pumps. Water is provided to the chamber sump as levels drop due to loss from evaporation. A float valve controls the addition of water to the system. If the integral humidifier needs to be isolated from inlet water a manual ball valve will be shut on the inlet water line. Duty and standby pumps provide water to the spray nozzles for application to packing material used to humidify process air. When the system is in automatic mode the pumps rotate duty operation every two (2) weeks. The pumps will only run in automatic mode only when the blower fans are operating. Manual control of the pumps will be available on the vendor supplied biofilter control panel. Flow switch indicators on the recirculation system and humidification sump purge lines will indicate an alarm and turn off the pumps to protect them if low flow through the pipe is detected. Similarly, a pressure indicator on the recirculation line will stop the pumps if the pressure becomes too high. Winter freeze protection will be provided by a sump immersion heater. The immersion heaters will not be used as part of normal operation; it will be turned on at the biofilter system control panel when operating the biofilter system during the winter months. A temperature indicator in the sump will trigger an alarm if the sump water becomes too cold or too hot. The heater will run when the operator entered low temperature set point is reached. In a similar fashion, the heater will stop when an operator entered high temperature limit is reached. As a safety measure in case the temperature control system fails, a high limit thermocouple on the heater sheath will turn off the heater when being run in both manual or automatic mode to protect it and the chamber at a temperature of 50oC.


The Thickening Building will be situated adjacent to the new Energy Centre (Contract 2a). It will be separated from the new Energy Centre building by expansion joint thereby giving the appearance of being one large building. The Thickening Building will be one storey in height with a basement level. Ground Floor will be comprised of control room, polymer and thickening room and polymer containment area. Basement will be comprised of pipe gallery, primary sludge holding tank, WAS holding tanks, thickened sludge holding tanks, thickening filtrate tanks, polymer feed pumps and stairwell. The entire basement will be cast in placed concrete structure, including the walls, interior columns and floor slabs. The superstructure is will be cast in placed column at approximately seven meters apart to support pre-stressed roof structure, and enclosed by pre-cast wall panels. The roof structure will be pre-stressed double tee units and pre-stressed beams. The usage of the pre-cast wall panels and roof structure will save at least two (2) months of construction time and eliminate the intermediate vertical support and provide greater working space. A monorail will be provided in thickening room to accommodate the service and maintenance of the equipment while an elevated equipment platform will be provided around thickening equipment for ease of maintenance. The floor will be finished with a protective epoxy coating.



The architecture of the Thickening Building will reflect the vision for all new buildings on the site. Situating the Thickening Building immediately adjacent to the new energy centre will give the appearance of being one large building due to the volumes of the two (2) building being combined. A staircase in between the two (2) buildings will project out in order to break the large mass. A change of material and horizontal banding of material will also be used to further break the massiveness of the structure and create more aesthetic proportions. A band of local cultured stone will be used for the first 3.5 m of the building elevation, followed by a band of white aluminum composite panels which is inset with red metal siding. The bands wrap around the buildings and are horizontally interrupted by the northeast staircase and a volume of grey corrugated metal siding. A series of louvered enclosures, which will house various equipment, add another layer to the architectural volumes. The overall composition, materials and proportions will be in harmony with the other new buildings on site. Using similar building materials throughout allows for economies of scale, ease of maintenance and cost efficiencies through bulk purchasing. Though LEED is not a requirement for this facility, sustainable ideas such as locally harvested and manufactured materials and effective day lighting will be used in this facility.



Indoor design conditions are summarized in Table 108. Table 108 Indoor Design Criteria for the Thickening Building

Areas Criteria

Control Room 24°C (summer) 50% RH / 22°C (winter)

Process Areas (Thickening, Polymer Room, Pump Room) 5~10°C unoccupied mode and 18°C for occupied mode (winter) / 5.5°C above outdoor temperature (summer)


Because ventilation rates are mandated by NFPA 820, a significant heating load is anticipated for the new facility. Gas fired unit heaters will provide supplementary heat for the process area. Electric unit heaters and baseboard heaters will provide heating for the non-process area. A preliminary heating load analysis shows that the max heating load for building will be approximately 3 million Btu/h. It is assumed that natural gas is available and will be used as a heating source.


The ventilation rates for the various Thickening Building areas are summarized in Table 109.



Table 109 Ventilation Rates for the Thickening Building Location And Function NFPA 820

Table and Row NFPA

Classification NFPA

Ventilation Rate Ventilation Rate and

Additional Notes

Thickening Building Basement Table 6.2(a)

Row 9 Line B

Unclassified Continuous ventilation

at 6 ACH

6 ACH

Thickening Building Polymer Room Area (Ground Floor) N/A Unclassified N/A 6 ACH

Thickening Building (Second Floor) Table 6.2(a)

Row 12 Line B

Unclassified Continuous ventilation

at 6 ACH

6 ACH

For unclassified process areas (pump, polymer and thickening areas) HVAC system will consist of one (1) gas fired AHU incorporating two (2) supply and two (2) exhaust fans, each fan with 100% of the required flow rate. Heat relief ventilation will be provided for the new Thickening Building. Systems serving these areas will feature equipment equipped with VFDs to enhance energy conservation and reduce maintenance cost (i.e. increase filter life span).


One ceiling mounted indoor AC unit will be installed in the Control Room to prevent electrical equipment from overheating.



Potable water will be supplied to the building for sanitary uses and polymer pre-dilution. Low water use plumbing fixtures and trim will be specified, and cross-connection control will be provided, in accordance with requirements of the OBC. Potable water will be metered at the building.


Plant service water will be supplied to the building for treatment process uses, including polymer post-dilution. Service water will be provided with a self-cleaning strainer where the service water enters the building. Two (2) booster pumps will be provided in the basement level of the Thickening Building. These pumps will be installed on the effluent water line to the building to boost the pressure in the treatment plant service water system to that required for RDT flushing.


Roof drains will be provided and will discharge to the treatment plant storm drain system.


Two (2) drain sumps, each equipped with duplex submersible pumps, will be provided in the basement of the Thickening Building. Building drain is pumped to the Thickening Filtrate Tank(s) for eventual pumping back to the primary clarifiers effluent flow splitting chamber.


The objective of the building sump system is to collect drainage from the Thickening Building and pump it to the thickening filtrate tank.



The building sump system, located on the basement level of the Thickening Building, consists of two (2) sumps, each equipped with two (2) submersible sump pumps (1 duty, 1 standby). High/low level floats are provided for pump control and HWL alarm. The drainage from the Thickening Building will be generated from the following process areas: Floor drains Odour control system

Under normal operating conditions, the building sump will be operated in the automatic mode. High/low level floats will be set up to start and stop the duty pump. Two (2) pumps will be assigned as duty and standby pumps. The duplex control panel will automatically assign individual pump duties based on pump availability and run time, and alternate pump operation between each duty cycle. Either pump may be selected as Duty 1 or Duty 2.


One combination safety shower/eyewash unit will be located inside the Thickening Building and provided with tempered water from emergency mixing valves. The shower/eyewash unit will be provided with a flow switch, light, and alarm bell. One (1) tankless water heater will provide required water for the emergency shower/eyewash unit. Electric power is available for domestic water heating.


The electrical design of the WAS thickening system is presented in detail in Section 17.







16. Miscellaneous Improvements to Existing Facilities 16.1 General Description

Drawings for the miscellaneous upgrades (Series 900) are contained in Appendix A.

16.2 Primary Clarifier Upgrades

16.2.1 Existing Primary Clarifier Facilities

The existing primary clarifiers are located in the south-central area of the Kitchener WWTP site. The structure consists of four (4) rectangular, half buried, open concrete tanks approximately two (2) stories high, and was built as part of the second expansion to the treatment facility in 1977. The primary sludge pumping building, also built in 1977, is a closed one storey concrete structure attached to the east end of the primary clarifiers. Some piping modifications were completed in 1987. Each primary clarifier is currently serviced by a travelling bridge to collect surface scum and settled sludge. Each primary clarifier has four (4) hoppers, and one (1) pump to transport primary sludge from the hoppers to the digesters. Primary Clarifiers 1 and 2 are serviced by a shared scum chamber and scum pump that transports scum to the raw sludge discharge header which continues to the digesters. Primary Clarifiers 3 and 4 handle scum in the same manner. The primary clarifiers are also currently used for the co-thickening of WAS. The four (4) primary clarifier tanks appear to be in good structural condition, although some minor improvements are required. The travelling bridges are more than 30 years old and nearing the end of their service life. The primary sludge pumping building is in good condition, except for the roof which has cracking, areas of exposed membrane and damaged flashing requiring repair. Pump replacement has been staged and there are currently three types of pumps in the primary sludge pumping building; the piston pumps are more than 30 years old and are in very poor condition, the vertical centrifugal pumps for tank unwatering are approximately 10 years old and are in fair condition, and the rotary lobe pumps with grinders were installed most recently and are in good condition. The new grinder (Rotocut®) and pumps have been prone to intermittent plugging; the problem is exacerbated by the existing piping configuration and smaller diameter piping provided to accommodate the 100 mm diameter pump suction.


The primary clarifiers currently have adequate process capacity for the rated capacity and peak flows of the Kitchener WWTP, and will not require significant modification or expansion. The existing traveling bridge collectors have multiple operating problems and will be replaced with chain and flight collectors, which will also allow for covering of the clarifiers in the future. With the new chain and flight system installed, scum collection will need to take place at the effluent end of the tank; therefore, the existing scum cross-collector will be removed and an actuated scum trough installed in front of the weirs. Scum from the troughs will flow into a scum collection tank, and then through an insulated scum pipe to the scum chamber. All of the existing sludge pumps and grinders will be replaced with new pumps and grinders with a simplified piping configuration to reduce the number of elbows and help to minimize potential for clogging. Implementation of separate WAS co-thickening is planned at the Kitchener WWTP; however, the new pumps were designed to have capacity for both separate and co-thickening since co-thickening will continue to be practiced until new thickening



facilities are installed and will provide a contingency measure in the future if bypass of thickening is required. The existing scum pumps will also be replaced with new pumps in the same fashion. Additional minor structural repairs are required for the tank walls and floors and roofing of the primary sludge pumping building. Replacement of steel covers over openings and aluminum gratings is recommended, as well as replacement of the building HVAC systems.

16.2.3 Process Design

16.2.3.1 Primary Sludge Collection Equipment

16.2.3.1.1 General Description

The primary clarifiers are each 19.5 m wide by 58 m long. These tanks are too wide to allow direct retrofit to chain and flight and will require an intermediate baffle wall. Four (4) equally sized sludge hoppers are located at the front of each tank. The tanks have two (2) longitudinal expansion joints located between sludge hoppers 1 and 2 and sludge hoppers 3 and 4. These expansion joints do not allow the tank to be divided into four (4) equally sized sections to accommodate chain and flights. The centres of the tanks are founded on a pile cap supported beam, which is the ideal location to install an intermediate baffle wall for chain and flights, resulting in a flight width of 9.5 m. At least two (2) vendors (Siemens and Polychem) produce a reinforced flight that can span 9.5 m with minimal deflection. A concrete platform accessed by an open grated walkway will be constructed at the east end of each primary clarifier to support the drive motors for each chain and flight.

16.2.3.1.2 Design Criteria

The design of the primary sludge collection equipment is based on handling an elevated sludge blanket (> 1 m) and raw sludge concentrations ranging from 2.5 to 5%, as shown in Table 110. Table 110 Design Criteria for Primary Sludge Collection Equipment

Parameter Criteria

Solids concentration range (%) 2.5 5

16.2.3.1.3 Preliminary Design Specifications

Table 111 presents preliminary design specifications for primary sludge collection equipment.



Table 111 Preliminary Design Specification for Primary Sludge Collection Equipment Item Parameter Specifications

Chain and Flights

No. of units 8 (2 per clarifier)

Carrier chains Working Load

Polymer composite, fibreglass or SS 20 kN, 11 kN, 22.4 kN

Flights Maximum deflection

Reinforced fibreglass flights 19 mm

Wearing surfaces UHMW Polyurethane

Chain sprockets UHMW Polyurethane

Chain and Flight Specifications

Width 9.5 m

Depth 3.7 m

Length 49.7 m

Drive Motor Number 8

Speed 0.5 m/min

16.2.3.2 Raw Sludge Pumping


New raw sludge pumps and grinders (optional) will be installed. The replacement pumps will be positive displacement rotary lobe units. The pump suction will be 150 mm diameter to match the hopper piping dimensions and installed to reduce the number of pipe elbows, minimizing the chance of clogging. Space has been allocated for optional future installation of grinders upstream of the pumps. It is unlikely that grinders will be required given that the new Headworks Building will be equipped with 6 mm perforated plate screens. If grinders are required, it is recommended that dual interlocking shaft-type units (e.g., Muffin Monster or equivalent) be utilized given their proven performance in handling a wide range of debris that may be present in raw sludge.

16.2.3.2.2 Design Criteria Table 112 presents the raw sludge pumping equipment design criteria, specifically the average and peak month primary sludge production at 2.5 to 5% solids. The pumps and grinders will be designed for a high sludge flow scenario, based on peak month primary sludge production without co-thickening (26,232 kg/d) at 2.5% solids, which would require a pumping rate of 12.2 L/s. Table 112 Design Criteria for Raw Sludge Pumping Equipment

Parameter Sludge Concentration and Flows

Separate Thickening With Co-thickening

Primary sludge production (kg/d) Average 18,698

Peak Month 26,232

Average 39,588

Peak Month 55,547

Solid concentration range (%) 2.5 5 2.5 5 2.5 5 2.5 5

Maximum primary sludge flow (m3/d) 748 374 1,050 525 1,584 792 2,222 1,111

Maximum primary sludge flow (L/s) 8.7 4.3 12.2 6.1 18.4 9.2 25.7 12.9 Notes:

1. Primary sludge production taken from PDM-4 Design Basis Summary


Table 113 presents the preliminary design specifications of the raw sludge pumping and grinding equipment.



Table 113 Preliminary Design Specification for Raw Sludge Pumping and Grinding Equipment Item Parameter Specifications

Raw sludge pumps

No. of units 4 duty (1 per clarifier), 2 standby

Capacity 12.2 L/s

Head 53 m

Horsepower 15 kW (20 hp)

Raw sludge grinders

No. of units 4 duty (1 per clarifier), 2 standby

Capacity 12.2 L/s

Horsepower 2.3 kW (3 hp)

16.2.3.2.4 Operating Philosophy Instrumentation and Controls

One pump will be dedicated to each primary clarifier, and one standby pump dedicated to each pair of primary clarifiers (i.e., one for primary clarifiers No. 1 and 2 and one for primary clarifiers No. 3 and 4). These standby pumps will also serve as standby scum pumps. Under normal conditions, the four clarifiers will be pumped on a 120 minute cycle timer (adjustable) with the start cycle for each clarifier equally staggered, as seen in Figure 25. This staggering of pumping allows for a more continuous raw sludge flow without overlapping of the pumping cycles during the design high flow scenario of 26,232 kg/d at 2.5% solids (with no co-thickening).

Figure 25 Typical Primary Sludge Pumping Cycle Based on a 120 Minute Cycle and 5 Minute Pump Time per Hopper at the Design Sludge Flow Rate

The ability will exist to overlap pumping cycles between individual primary clarifiers while still providing a reasonable velocity, as may be required during periods of co-thickening and low sludge concentration. This operation provides increased system flexibility and redundancy even when pumping cycles overlap. All raw sludge pumps will be equipped with a high pressure hardwired interlock to prevent damage.

16.2.3.3 Scum Removal


The scum removal equipment consists of two scum troughs per clarifier, each controlled by a motorized worm gear actuator at the effluent end of the primary clarifiers. The scum troughs will be connected through the concrete divider wall, and they will empty into a scum collection tank located in between two clarifiers, one for primary clarifiers No. 1 and 2 and one for primary clarifiers No. 3 and 4. The scum collection tanks will empty through a sloped insulated and



heat traced scum pipe into the existing scum chambers at the influent end of the clarifiers. The scum pipe will also be equipped with an effluent water flush for periodic flushing. Scum pumps located in the pumping building will empty the scum chambers and pump the scum to be combined in the common header with raw sludge being pumped to the primary digesters.


Scum trough design was based on a single scum trough being three quarters full upon tipping, and a subsequent scum flow of 1 m/s for 30 seconds to the collection tank, allowing for a scum flow of 7.2 m3/d from each clarifier. This collection would occur intermittently for each clarifier, requiring the scum pumps to operate three times per day. The scum pumps will be designed to match the raw sludge pumps for interchangeability.


Table 114 presents the preliminary design specifications of the primary clarifier scum removal equipment. Table 114 Preliminary Design Specification for Primary Clarifier Scum Removal Equipment

Item Parameter Specifications

Scum Trough


Diameter 0.45 m

Length 9.8 m

Scum Pipe

Diameter 0.45 m

Length 52.7 m

Slope 1.5 %

Approximate Velocity 1 m/s

Scum Chamber Available Volume 8 m3

Scum pumps

No. of units 2 (1 per 2 clarifiers)

Capacity 12 L/s

Head 53 m

Horsepower 15 kW (20 hp)


The scum tipping troughs in each clarifier will operate on a cycle timer as follows: Scum Trough A will open to X% (adjustable) for Y min (adjustable) following which it will close. Scum Trough B will open to X% (adjustable) for Y min (adjustable) following which it will close.

An ultrasonic level sensor is located in each scum chamber to automatically start the duty scum pump at high level and stop the pump at low level. A permanently plumbed effluent water flush line is provided to the insulated sloped scum pipe at the effluent end of the clarifier. Operators can manually turn the effluent flush on as required to scour the scum line. All scum pumps will be equipped with a high pressure hardwire interlock to prevent damage

16.2.4 Architectural and Structural Design

The physical condition assessment identified architectural deficiencies related to the primary sludge pumping gallery. The following architectural upgrades will be provided: New thermo-pane windows New roofing; the built up roofing has cracking, exposed membrane, damaged flashing, and the pitch pockets for

roof penetrations have dried up



Upgrades to address these deficiencies will be included with the other primary clarifier upgrades. It should be noted that the existing building does not meet the design flood protection levels and it is not feasible to modify the building to achieve flood protection. In order to support the chain and flight systems, a structural support system will need to be erected down the centre of each primary clarifier. The system will consist of a number of concrete piers and columns that will support a concrete or precast concrete beam line that will anchor the guides for the chain and flight system. Larger concrete piers will anchor the system at each end of the tank, supporting the sprockets for the chain and flight. Primary clarifier tanks are currently supported by and founded on piles with fixed design loads; therefore, the new structure must be made with as little mass as possible so that the existing foundations are not overloaded. The column and beam system will accomplish this task; the columns and piers will be located along a pile grid line and most new columns and piers will be located centrally over existing pile caps. The base slab of the tank will not be able to sustain bending moment loading caused by horizontal loading of the new column and beam line. It is therefore necessary to brace the new column and beam line via horizontally spanning tension and compression structural members, anchored to existing tank walkways capable of receiving these loads. Precast concrete beams are recommended for this system to accelerate schedule and reduce cost. However, if preferred by the contractor, a cast in place concrete beam system can be used with relative ease, but with significant cost and construction period extension. The tank is composed of several concrete watertight structures separated by these expansion joints that move, expand and contract independently of each other. The new structural system must allow for these movements at each and every joint, including: Joints in the concrete beams supporting the guides for the chain and flight system Slotted connections in the steel beams supporting the new walkway spanning over expansion joints Slotted connections in the steel braces horizontally supporting the new system that span over expansion joints Horizontal joints on the base slab surface where the concrete end piers are required to span over the

expansion joints. A concrete platform will be constructed at the east end of the tanks to support the drive motors in order to keep the walkways on either side of the clarifiers clear. This platform will be accessed by a grated walkway.

16.2.5 Building Mechanical Design

16.2.5.1 Heating, Ventilation and Air Conditioning

16.2.5.1.1 Heating Systems


16.2.5.1.2 Ventilation Systems

Ventilation is provided by two (2) axial wall fans interlocked with two (2) fresh air intake dampers. The ventilation equipment is corroded and looks to be in poor condition. This equipment will be replaced with the other primary clarifier upgrades. The fans provide a total capacity of 5,600 m3/hr; equivalent to only two (2) ACH. NFPA 820 suggests 6 ACH for primary sludge and scum pumping galleries to unclassify the enclosed area.



The existing fans and intake louvers will be replaced with larger units to provide a total ventilation rate of 16,000 m3/h, equivalent to 6 ACH in the primary gallery. The existing hydronic unit heaters will be replaced and additional heaters will be provided for a total heat demand of 180 kW supplied from the existing boilers.

16.2.5.1.3 Air Conditioning System

Not applicable.

16.2.5.2 Plumbing and Drainage


16.2.6 Electrical Design

The existing primary sludge pumping gallery houses 2 MCCs: MCC 8 and MCC 9. MCC 9 currently powers the Plant 2 mechanical aerators and a few small miscellaneous loads in the primary sludge pumping gallery. Once the new blower building is commissioned, the majority of the load in this MCC will be removed. MCC 8 services the primary sludge and scum pumps and travelling bridge loads. This MCC is showing some signs of corrosion and will be at the end of its service life once this project is completed. As a result, a single new MCC will be installed to replace both MCC 8 and MCC 9. Overall loads for the new MCC will be similar that currently on MCC 8. The electrical design of the miscellaneous upgrades is presented in detail in Section 17.

16.2.7 Instrumentation and Control Design

A new control panel meeting the Region’s standards will be provided adjacent to the new MCC. All remaining existing I/O and new I/O will be transitioned through this new control panel. Instrumentation and control design is presented in Section 18.6.

16.2.8 Construction Sequencing, Tie-Ins and Demolition

Work on the primary clarifiers and the pump replacement will be completed sequentially (one unit at a time) and commissioned prior to beginning work on the next primary clarifier. As a result, only one primary clarifier and its associated sludge pump will be removed from service at a time for construction.

16.3 Plant 2 Secondary Clarifier Upgrades

16.3.1 Existing Plant 2 Secondary Clarifiers

The existing Plant 2 secondary clarifiers are located north of the existing Plant 2 aeration tanks. There are four (4) circular secondary clarifiers, each 33.5 m in diameter with 3.0 m SWD. The existing secondary clarifiers are centre feed with draft tube type sludge withdrawal across the diameter of the clarifier to a central well feeding a 600 mm RAS line. The secondary clarifiers are not equipped with secondary scum collection. The four (4) Plant 2 secondary clarifier tanks appear to be in good structural condition, but the mechanisms are nearing the end of their useful life.


Plant 2 will continue to remain in service to treat an average flow of approximately 40,000 m3/d, with the remainder of the capacity being provided by the new Plant 3 and 4. The existing clarifier mechanisms will be replaced with new



mechanisms. While the clarifier mechanism are replaced, a secondary scum collection system will be added and the launder elevations raised by approximately 200 mm to provide additional freeboard capacity with the downstream tertiary filtration facility. Secondary scum will be collected in two (2) pre-cast, duplex submersible pumping stations and pumped to the WAS discharge header for separate thickening or co-thickening. Each pumping station will service two (2) secondary clarifiers.

16.3.3 Process Design

16.3.3.1 Secondary Clarifier Mechanisms


The secondary clarifiers are each equipped with a RAS withdrawal pipe located concentrically within the influent feed pipe. New centre column feed supported mechanisms will be provided to match the existing mechanisms but will be slightly deeper to accommodate the 200 mm increase in launder elevation (i.e., 3.2 m SWD). The new mechanisms will be equipped with a spiral sweep to ensure rapid transport of sludge to the centre of the clarifier. The existing siphon-type sludge withdrawal tubes will be replaced with a base mounted rotating collection drum to direct all sludge to the existing RAS pipe. The new mechanism will also be fitted with a scum collection arm designed to lift secondary scum over a peripheral beech plate. The scum beech plate will be located adjacent to the access walkway to simplify washdown as required. The clarifier drives will be equipped with a torque monitor to set off an alarm and shut-down in case of high torque conditions.


Table 115 presents design criteria for the secondary clarifier collection equipment. Table 115 Design Criteria for Secondary Clarifier Collection Equipment

Parameter Criteria

Minimum Maximum

Solid concentration range (%) 0.5 1


Table 116 presents preliminary design specifications of the secondary clarifier mechanism. Table 116 Preliminary Design Specification for Secondary Clarifier Collection Equipment


Clarifier Mechanism


Type Column Supported, Spiral Sweep

Diameter 33.5 m

Side Water Depth 3.2 m

Drive Motor Number 4

Speed 0.03 rpm

16.3.3.2 Secondary Scum Pumping


Two new secondary scum submersible pumping stations will be used to collect and pump secondary scum to the WAS discharge header. The preferred tie-in location will be coordinated with the Plant 2 RAS/WAS pumping station upgrades. The wet well will consist of a 1.8 m diameter pre-cast chamber with the bottom depth and top of concrete



matching that of the secondary clarifiers. As a result, any malfunction in the scum pumping station will back-up into the secondary clarifier without causing any spill to the adjacent grounds.


Table 117 presents the design criteria for the secondary scum pumping facility. Table 117 Design Criteria for Secondary Scum Pumping

Parameter Sludge Concentration and Flows for Various Scenarios

Secondary Scum Production (m3)

Per Secondary Clarifier 900 L/hr (500 L/revolution)

Total per Station 1.8 m3/hr

Total (2 stations) 3.6 m3/h

Solid concentration range (%) 0.2 (minimum) 2.0% (maximum)


Table 118 presents the preliminary design specifications of the secondary scum pumping equipment. Table 118 Preliminary Design Specification for Secondary Scum Pumping Equipment


Wet well

No. of units 2 (1 per pair of clarifier)

Diameter 1.8 m

Depth 3.8 m

Approximate Cycle Volume per wet well 3.8 m3

Secondary Scum Pumps

No. of units 4 (2 per wet well)

2 standby

Type Submersible

Capacity 9.4 L/s

Horsepower/TDH TBD

Discharge Forcemain 100 mm diameter; 1.2 m/s


One duty pump and one stand-by pump will be assigned to each wet well, with each wet well servicing a pair of secondary clarifiers. Scum will be directed to the wet well intermittently, once per clarifier revolution, as the scum rake arm pushes scum over the bench plate. The wet well will be equipped with an ultrasonic level sensor for pump control. Pump control will be as follows: Duty pump will start once every X hours (e.g., 4 hours) and stop at the low water level set-point If the high water level set-point is reached prior to the timer elapse, the duty pump will automatically start and will

stop at the low-level set-point Duty pump will rotate every cycle

16.3.4 Architectural and Structural Design

Not applicable.

16.3.5 Building Mechanical Design

Not applicable



16.3.6 Electrical Design

The electrical design of the miscellaneous upgrades is presented in detail in Section 17.

16.3.7 Instrumentation and Control Design


16.4 Service Water System

A new service water system is currently being installed in the new UV Disinfection Building to supply the plant with effluent water to satisfy various water demands. The system consists of three (3) vertical turbine pumps, each with capacity for 20 L/s at 75 m TDH (106 psi). Automatically cleaned strainers are provided in the discharge header downstream of the pumps. Table 119 summarizes the estimated plant-wide effluent water demands. A detailed breakdown of demands is provided in Appendix M. Table 119 Effluent Water Demands

Process Area Continuous Demand Intermittent Demand Distributed Demand (continuous plus 50% intermittent)

Headworks

Low Pressure/Low Quality Water Required 20.0 L/s 30.0 L/s 35.0 L/s

High Pressure/High Quality Water Required 20.0 L/s 10.0 L/s 25.0 L/s

Primary Treatment - 3.8 L/s 1.9 L/s

Aeration Tanks - 9.0 L/s 4.5 L/s

Secondary Clarifiers - 6.6 L/s 3.3 L/s

RAS/WAS Pumping - 4.4 L/s 2.2 L/s

Thickening 9.0 L/s - 9.0 L/s

Digestion 4.0 L/s 2.0 L/s 5.0 L/s

Total

With All Headworks 53.0 L/s 65.8 L/s 85.9 L/s

Without Headworks Low Pressure 13.0 L/s 35.9 L/s 50.9 L/s

The plant headworks has high volume demands (50 L/s), with the most significant demands being screenings sluice water, grit chamber fluidization and grit pump suction fluidization. These sources do not require high quality effluent water and do not require high overall pressures. Therefore, it may has been determined that a separate local system be constructed to service this demand. Excluding the high headworks water demands, the peak distributed plant-wide effluent water demand is estimated at 50.9 L/s. This water demand can be met by the three (3) effluent water pumps in the UV Building (total installed capacity of 60 L/s). If one pump is out-of-service in the UV Building, two pumps can provide 51 L/s but the system pressure at the UV Building reduce to 60 m (85 psi) compared to the normal operating pressure of 76 m (106 psi). The new EPS will be maintained in the UV Building and a new localized high volume, lower quality source for the Headworks Building using screened and degritted effluent will be provided, as discussed in Section 10.3.4. It is recommended that the tertiary filter building effluent channel be equipped with a pipe stub and blind flange to allow additional effluent pumping to be installed in the filter building basement if required in the future.

16.5 Plant 1 Decommissioning

Plant 1 Aeration Tanks have been operating for almost 50 years. An interim upgrade was recently completed to improve the aeration system’s performance and to treat more flows. With the construction of new Plant 3 and 4



Secondary Treatment, Plant 1 Secondary Treatment will be decommissioned in 2018 The scope of work of decommission of aeration tanks includes the following items: Tank cleaning to be completed to remove accumulated sludge at the bottom of the tank Removal of aeration tank equipment (e.g. isolation gates, diffuser discs, air dropleg, distribution headers and

associated valves and instruments) Removal of secondary clarifier mechanisms, piping, pumps and associated equipment Removal of concrete includes aeration tanks, influent channels, effluent channels and RAS channels. Concrete cutting Disposal materials offsite Backfill the demolished area up to the finish grade (i.e. 281.81m) with selected materials. Area to be topped with

soil and seed. Demolition and removal of existing electrical/pumping building Removal of interim blower building Backfill, grading and site restoration

Two (2) High Speed Turbo blowers are being installed in a temporary blower enclosure located adjacent to the Plant 1 Aeration Tanks (see Figure 26). The two blowers are designed to be used to supply air for Plant 3 and 4 aeration systems. These blowers will eventually be relocated in a new Blower Building, which are currently under construction as part of the Plant 2 upgrades.

Figure 26 Relocation of Plant 1 Blowers

New Blower Building Plant 1

Aeration Tank

Temporary Blower Enclosure

Plant 1 Secondary Clarifiers



17. Electrical Design and Energy Centre (Contract 2a) Energy Centre drawings (Series 700) and electrical design drawings (Series 1000) are contained in Appendix A.

17.1 Existing Electrical Distribution System

17.1.1 General

The primary power supply to the Kitchener WWTP is based on a 13.8 kV utility feed. The 13.8 kV primary power is provided by Kitchener Wilmot Hydro. The primary 13.8 kV feeds consist of overhead aerial distribution that terminates at an existing outdoor 13.8 kV to 600V main substation. The substation provides 600V, 3 phase power distribution to service the respective process systems and building loads located at the Kitchener WWTP. The 600V power distribution from the substation is routed to the respective WWTP loads via underground and above ground duct banks.

17.1.2 13.8 kV Primary Power Distribution

The 13.8 kV primary distribution at the Kitchener WWTP is based on aerial, non-insulated conductors. The 13.8 kV primary distribution is provided by Kitchener Wilmont Hydro via two (2) separate overhead primary circuits. The first 13.8 kV overhead primary circuit enters the Kitchener WWTP site from the south side of the plant and the second 13.8 kV primary circuit from the north side of the plant. The two (2) 13.8 kV primary circuits terminate at the existing 13.8 kV to 600V outdoor main substation located on the south side of the WWTP across from the Plant 1 Aeration Tank.

The north and south 13.8 kV aerial feeders terminate to two (2) separate 13.8 kV to 600V transformers located in the outdoor substation. Each transformer is fed via a 13.8 kV insulated cable drop from a utility hydro pole. The north 13.8kV aerial feeder provides 13.8 kV primary power to the outdoor substation 13.8kV to 600V transformer TX No. 1. The south 13.8 kV aerial feeder provides 13.8 kV primary power to the outdoor substation 13.8 kV to 600 V transformer TX No. 2.

The two (2) 13.8 kV primary circuits are connected to a pole mounted aerial interrupter switch. The interrupter switch allows for the interconnection of the two (2) aerial 13.8 kV circuits. In the event that one (1) 13.8 kV utility feeders was out for service, it is possible to close the aerial tie switch and restore 13.8 kV primary power to the affected 13.8kV to 600V transformer.

17.1.3 Main Outdoor Substation

The existing main outdoor substation is the main source of power distribution to the Kitchener WWTP. The existing substation consists two (2) 13.8 kV to 600 V transformers, and 600 V, 3 phase metal enclosed distribution switchgear.

The main service transformers are pad mounted tamper proof type. Each transformer is equipped with an integral 13.8 kV fused interrupter switch to suit the primary transformer over current protection. The transformers are designated TX#1 and TX#2. The two (2) transformers each have the same electrical name plate rating as follows:

2500 kVA, 13.8 kV to 600V, 3 phase, Delta Primary, Wye Secondary (Oil Filled – Tamper Proof) Solid

Secondary Ground.

The main substation includes a 600V, 3 phase, 4 wire outdoor switchgear system. The 600 V switchgear is metal enclosed with gasketed front doors for outdoor applications. The switchgear consists of seven (7) 600V switchgear cells. The 600V switchgear is configured as a secondary selective system with two (2) main breakers and a tie



breaker . The main and tie breakers are equipped with mechanical key interlock systems to prevent the connection of the TX1 and TX2 utility sources.

Each main breaker services a 600V, 3 phase, 4 wire distribution bus. The main transformer breaker for TX#1 services the 600 V bus designated BUS A. The main transformer breaker for TX#2 services the 600V bus designated BUS B. In the event that BUS A or B 600V main breaker feeder is unavailable, the respective main breaker can be opened and the bus tie breaker can be closed such that all 600V load is supplied via one main transformer. The 600V main outdoor switchgear BUS A and B are rated 2500 A, 3 phase, 4 Wire, 65 kA. The switchgear includes seven (7) free standing distribution cells. The respective cells include the following distribution breaker amp ratings and application load (Cell No.1 starting from the east end of the switchgear and going west are as follows):

Cell No.1: 400 A – MCC 11 Screw Pump, 600A – MCC No. 10 Screen Building, 600A – Spare Breaker Cell No.2: 2500 A – Transformer TX No. 1 BUS A Main Feed Cell No.3: 400 A – MCC#5 Sludge Pump Building, 400A – MCC No.6 Chlorine Building, 1200 A – MCC No. 9

Aeration Building Cell No.4: 2500 A BUS Tie Breaker Cell No.5: 200 A – Distribution Panel Filter/Admin Building, 600 A – MCC No. 4 Aeration, 1200 A – Spare

Breaker Cell No.6: 2500 A – Transformer TX No. 2 BUS B Main Feed Cell No.7: 400 A –MCC No. 7 Digester Building, 400 A – MCC No. 2 Old Admin Building., 600A – Spare

Breaker.

The Kitchener Wilmot Hydro revenue CT/PT sensing is installed in switchgear cells No.2 and No.4 on the secondary of respective main breakers. A metering cabinet is located on the west end of the 600V switchgear that contains the Kitchener Wilmot Hydro Revenue Meters.

17.1.4 Standby Emergency Power

The Kitchener WWTP is equipped with one (1) emergency standby generator. The generator is dedicated to power to the existing Administration Building and the Boiler Room. No other buildings at the Kitchener WWTP are provided with emergency power. The existing Administration Building is provided with 600V normal power distribution from the outdoor main substation. The Administration Building main service entrance breaker is rated 400A, 600V, 3 phase. The Administration Building includes a 600V, 3 phase emergency power supply in the event that the normal utility power provided by the main substation is unavailable. The emergency power is provided by an outdoor Natural Gas Fuelled Emergency Generator. The generator is located in a pad mounted sound attenuated outdoor enclosure, on the west side of the Administration Building. The Administration Building is equipped with an automatic transfer switch (ATS). In the event of a normal power failure, the ATS will automatically start the generator and transfer the Admin Building 600V Loads to emergency power. The generator provides emergency power to suit the general building services including lighting, power distribution / receptacles, and HVAC equipment. The natural gas generator is rated as follows: 150 kW, 600 V, 3 Ph., 0.8PF

The Administration Building 600 V distribution system includes a 60 A, 600 V, 3 phase feeder that is routed to the Boiler Room. In the event of a power failure, the existing Boiler Room will be provided with emergency power via the Administration Building emergency generator.



17.2 General Power Distribution

The Kitchener WWTP site distribution is based on 600 V, 3 phase power. The main substation provides 600 V, 3 phase power feeders to the respective buildings and process loads. The 600 V power distribution is routed to the respective buildings and process loads via power conductors installed in underground and above ground conduits. The respective buildings and process equipment at the site are equipped with 600 V Motor Control Centers (MCC) and/or 600 V Power Distribution Panels (PDP). The following existing MCCs and PDPs provide 600 V power distribution to the respective Kitchener WWTP buildings and process equipment: MCC No.2: Old Administration Building-Basement PDP-01: New Administration Building MCC No.4: Aeration Tank No.1-Electrical Room MCC No.5: Plant No.1 Sludge Return Building. MCC No.6: Chlorine Building MCC No.7: Digester Complex MCC No.8: Primary Clarifier Pump Gallery MCC No.9: Primary Clarifier Pump Gallery (Aeration Tank No.2 – Surface Aerators) MCC No.10: Headworks MCC No.11: Screw Pump Building – Plant 2 RAS/WAS

17.3 Interim Distribution System Upgrades-By AECOM

17.3.1.1 Interim Aeration Tank N0-1

The Kitchener WWTP has been provided with a new Interim Blower Building to suit Aeration Tank No.1. The new blower building was designed based on a pre-fabricated package that included the building, blower equipment and basic electrical distribution within the building. The pre-fabricated building supplier provided pre-wired 120/208 V distribution within the building to service the general power distribution, including lighting and receptacles. A 600 V, 3 phase, 1200 A distribution panel was installed in the interim blower building to service the 600V, 3 phase blowers (2) and other 600V auxiliary loads within the building. The 600 V, power for the interim blower building was sourced from the existing outdoor 600 V substation and switchgear. An existing 1200 A, 600V breaker located on BUS B of the existing outdoor 600 V substation was utilized to feed the interim blower building. Power distribution to the new interim blower building was installed in new below grade conduits. Once the Plant 3 and 4 secondary treatment trains are constructed, the interim blower building will be decommissioned and removed. The two (2) blowers located in the temporary blower building will be relocated to the Plant 3 and 4 Upgrades under Contract 4.

17.4 Distribution System Upgrades (Phase 2 Upgrades)

17.4.1 New 13.8kV Primary Outdoor Switchgear

Under the scope of work of the Kitchener WWTP Phase 2 Upgrades new outdoor 13.8 kV primary switchgear designated KITSWG01 will be installed to serve as a new point of connection for the two (2) Kitchener Wilmot Hydro primary circuits and provide a point for distribution of 13.8 kV to the new Plant 2, 3000kVA transformer substation and existing outdoor 600 V switchgear designated KITSWG02 to service the Plant 2 Blower MCC-B1. Once installed, the 13.8 kV distribution will be provided to the following locations: Existing outdoor 13.8kV/600V outdoor substation and 600V switchgear



Plant 2 Blower Building KITSWG02

The new KITSWG01 13.8 kV switchgear will consist of a secondary selective distribution architecture, with two (2) main breakers and a tie breaker. The switchgear Bus and main breakers are rated 15 kV, 600 A, 3 phase. The switchgear will include sensing sections to suit PT/CTs for Kitchener Wilmot Hydro Revenue Metering. Note that revenue metering at the existing main outdoor substation will be removed. The secondary side of each main breaker, in the new 13.8 kV substation will be equipped with Utility revenue metering. The existing 13.8 kV aerial circuits provided by Kitchener Wilmot Hydro will be relocated to the new 13.8 kV substation and will be terminated to the respective substation main breakers.

The 13.8kV substation will include three (3) load breakers to supply power to the Kitchener WWTP. Two (2) new load feeders will supply power to the existing outdoor substation, located adjacent to Aeration Tank No.1. The 13.8 kV aerial primary circuits that currently feed the existing outdoor substation will be disconnected and redirected to the new 13.8 kV substation. The third 13.8 kV load feeder breaker will supply power to the new Plant 2 Blower Building 13.8 kV to 600V transformer.

17.4.2 UV Disinfection And Effluent Pumping Upgrades

Included in the scope of work of the Kitchener WWTP Phase 2 Upgrades are new UV disinfection and effluent pumping systems. The scope of the electrical upgrades to suit the UV disinfection and effluent pumping systems will include the installation of new 600 V, 3 phase MCCs .The 600V power distribution for the new MCC s will be sourced from the existing outdoor substation. A new 1200 A feeder breaker will be installed on BUS A of the existing outdoor 600V substation to suit the UV MCC 600 V power supply. A new 2000 A feeder breaker will be installed on BUS B of the existing outdoor 600 V substation to suit the UV MCC 600 V power supply. Power distribution to the respective new MCC loads will be installed in below grade conduits. No emergency power generation will be installed as part of the UV disinfection and effluent pumping systems upgrades.

17.4.3 Plant 2 Blower Building Upgrades

The Plant 2 blower building upgrades includes the Installation of new blowers in a new blower building. The scope of the electrical works to suit the Plant 2 upgrades will include the installation of new 13.8 kV and 600V distribution systems. The new Plant 2 Blower Building will include a 3000 kVA, 13.8 kV to 600 V, 3 Phase, 4 wire power transformer and outdoor 600 V, distribution switchgear. The new transformer and switchgear will be located adjacent to the new blower building. The outdoor 600 V switchgear will include a 2000 A, 600 V feeder breaker that will supply a new MCC located in the blower building that is designated MCC-B1. The new MCC-B1 will provide 600V power distribution to suit the respective new blower building process loads. No emergency power generation will be installed as part of the Plant 2 Process Upgrades.

17.5 Distribution System Upgrades As Part of Preliminary Design

17.5.1 General

The design of new electrical distribution to suit the Plant 3 and 4 upgrades will include a 13.8 kV power distribution switchgear located in new energy center to service the respective process and building loads at the Kitchener WWTP. The 13.8 kV distribution architecture will provide a secondary selective distribution system that will include two (2) main service breakers, dual 13.8 kV load BUS, and tie breaker based on IEEE Standard 141-1986 Recommend Practice of Electric Power Distribution for Industrial Plants. The 13.8 kV dual load BUS will include load distribution breakers to service the respective process and building loads at the Kitchener WWTP. The switchgear will also serve as an emergency bus for the emergency power generators.



The new 13.8 kV switchgear in the Energy Center will be fed from the outdoor primary switchgear KITSWG01 installed under the Phase 2 upgrades. The primary 13.8 kV feeders will supply power to the 13.8 kV distribution system. In the event that one (1) 13.8 kV feeder fails, the operational feeder can provide 13.8 kV power to the affected bus via the tie breaker. The secondary selective architecture will also be provided to suit the 600V distribution such that all new building/process loads fed from the new switchgear will provide the same redundancy/reliability as the 13.8 kV distribution. The new Energy Center 13.8 kV distribution will provide power feeders to suit existing and new 13.8 kV to 600 V loads. Additional 13.8 kV to 600 V transformer capacity will be provided to service the Plant 3 and 4 Process upgrades. New 13.8 kV to 600V transformers will be provided to service the respective new process building loads including thickening/digestion, headworks, and tertiary filtration. Local 13.8 kV to 600V transformers will be provided to service the new process building loads. The local transformers will ensure that the lengths of low voltage 600 V conductors is minimized which will result in lower cable losses and reduced quantifies of large copper conductors. The new Energy Center will be the primary point of 13.8 kV distribution to service the Kitchener WWTP electrical loads. The new and existing 13.8 kV loads will be provided with 13.8 kV breaker feeders from the new Energy Center. The following loads will be supplied from the new Energy Center: Existing Outdoor Substation: 2 x 13.8 kV to 600 V Transformers Plant 2 – Blower Building: 2 x 13.8 kV to 600 V Transformer New Headworks Building: 2 x13.8 kV to 600 V Transformers New Thickening/Digestion Facility: 2 x13.8 kV to 600 V Transformers-Dry Type New Tertiary Treatment Facility: 2 – 13.8 kV to 600 V Transformers

The Plant 3 and 4 upgrades will require that emergency power is provided to specific process systems during loss of normal utility power conditions. Emergency power will be integrated into the new 13.8 kV Energy Center distribution switchgear. The use of 13.8 kV emergency power generation will eliminate the need for any intermediate transformation to service the respective WWTP loads. Typical emergency generator products can be provided with standard alternator voltages that include 13.8 kV. The new 13.8 kV emergency power generation will be connected to the Energy Center 13.8 kV distribution switchgear such that all Kitchener WWTP loads will have access to emergency power. The Energy Center 13.8 kV switchgear will be capable of providing both normal and emergency power via that same 13.8 kV distribution system. The main utility 13.8 kV service feeders and generator breakers will be located in a common switchgear arrangement, which allows for the implementation of utility parallel generation, including co-generation, peak shaving and base loading operations. The use of utility paralleling technology provides a synchronized (bumpless) transfer from emergency power to normal power, once the failed Utility is restored, eliminating the second power interruption to process systems when returning to normal power. A synchronized retransfer will soft load the plant equipment from the generator to the utility in a controlled manner. The combined generator capacity will be synchronized to service all site loads. Plant process SCADA control may be utilized to limit the operation of respective process systems to ensure that the generation capacity is not exceeded during emergency operations. The installation of the new Plant 3 and 4 process systems will result in additional electrical loads at the Kitchener WWTP. The process loads at the Kitchener WWTP are distributed around a large area. The utilization voltage for all equipment and general distribution at the Kitchener WWTP will be based on 600 V power. The existing (and/or future Plant 2) 13.8 kV to 600 V transformers do not have sufficient capacity to suit the load requirements of the new Plant 3 and 4 Upgrades. The size of the site and distances between process loads prohibits the use of low voltage 600 V site distribution due to high cable losses and large copper conductor sizes. A site wide distribution voltage is



required to efficiently deliver power to the respective building loads at a higher voltage and reduced cable losses and cable sizes. The standard high voltage options for delivering power distribution are 4160V, 13.8 kV and 27.6 kV. The use of 4160 V and/or 27.6 kV power distribution is not feasible given that there are no loads that utilize 4.16/27.6 kV. The recommend solution for distributing power to the Kitchener WWTP site is to provide 13.8kV distribution. The 13.8 kV primary site distribution voltages will match the Utility Feeder voltage level and eliminate the need for any intermediate transformation.

17.5.2 Contract 1b – Digested Sludge Transfer Pumping

The location of Contract 1b work is in the existing administration building. Under Contract 1b, the existing 25Hp bio solids transfer pumps will be removed and replaced with new 150Hp transfer pumps with VFD starters. To accommodate the increase in electrical load the existing 400 amp, 600 V power feed from the existing outdoor 600 V switchgear will be upgraded to a new 600 amp, 600 V power feed. A spare 600 amp breaker in the existing outdoor 600V switchgear will be utilized to provide the increase in power supply. A new MCC designated as MCC-01/02 will be provided in addition to two (2) new VFDs to suit the increase in electrical service to 600 amps. The MCC will be designed with two (2) main breakers and tie breakers to suit power supply from two (2) sources. Until Contract 2a is completed, there will only be one (1) 600V feed from the existing outdoor switchgear. Once Contract 2 is complete, a second 600 V power feed will be provided from the new Energy Center. The VFDs will be designed as ultra low harmonic VFDs. All existing distribution in the existing administration building will be re-fed from the new MCC and retained as is. In addition, the existing 150 kW gas generator will be retained for purpose of providing emergency power until Contract 2 is completed.

17.5.3 Contract 2a – Energy Center

The Energy Center will include new 13.8 kV switchgear and emergency power generation. The new 13.8 kV switchgear in the Energy Center will be fed from the outdoor 13.8 kV KITSWG01 switchgear with two (2) underground feeders. Under the scope of this Contract two (2) new underground 13.8kV feeds will be provided to the existing outdoor 13.8kV/600V substation from the new 13.8kV switchgear.. In addition the 13.8kV power feeds to KITSWG02 will be re-routed to suit power feeds from the new 13.8 kV switchgear in the Energy Center. Connection will be made in the existing electrical manholes where the existing 13.8 kV power distribution transitions from underground to above grade on the underside of the influent duct structure. The Energy Center will be provided with 2-1500kVA, 13.8 kV/600 V dry type transformers to provide 600 V power feeds to the following: Energy Center 600 V loads Primary Digester MCC-03 Existing Administration Building Polymer Thickening Equipment Installed Under Contact 5b



17.5.4 Contract 2b – Anaerobic Digestion

Upgrades to the primary digestion include a new electrical room and MCC designated as MCC-03-01/02. The MCC will be fed at 600V from the energy center and will be designed with two (2) main breakers and tie breaker to suit power supply from two (2) sources. Existing MCC-07 will be retained as is and will be re-fed from MCC-03

17.5.5 Contract 3a – Headworks Building

The new Headworks Building will be fed from the Energy Center constructed in Contract 2a and will include a new electrical room and MCC designated as MCC-04-01/02. The power feed to the Headworks Building will be at 13.8 KV and will include two (2) outdoor 13.8 kV/600 V transformers located in close proximity to the Headwork Building. A new electrical duct bank will be constructed for purpose of routing the 13.8 kV distribution from the Energy Center 13.8 kV switchgear to the Headworks Building.

17.5.6 Contract 3b – Tertiary Filtration Building

The new Tertiary Filtration building will be fed from the Energy Center constructed in Contract 2a and will include a new electrical room and MCC designated as MCC-xx-01/02. The power feed to the Tertiary Filtration Building will be at 13.8KV and will include two (2) outdoor 13.8 kV/600 V transformers located in close proximity to the Tertiary Filtration Building. A new electrical duct bank will be constructed for purpose of routing the 13.8 kV distribution from the Energy Center 13.8kV switchgear.

17.5.7 Contract 4 – Plant 2 Blower Building

The electrical work associated with the Plant 2 blower building includes providing a second 3000 kVA, 13.8 kV/600 V transformer and retrofitting the outdoor 600 V switchgear KITSWG02 to provide a second main breaker and tie breaker to provide a secondary selective arrangement. A new 13.8 kV feeder will have to be run from the energy centre to the new transformer. A new MCC designated as MCC-B2 will be provided to suit providing power distribution associated with the installation of seven new blowers.

17.5.8 Contract 4 – RAS/WAS Pumping Stations

The new MCCs in the Plant 2,3 and 4 RAS/WAS will be fed from the Plant 2 KITSWG02 (Blower building outdoor switchgear) via 600 V underground distribution.

17.5.9 Contract 5a – New Administration Building

All electrical loads associated with the new administration building will be provided 600V from the Headworks Building.

17.5.10 Contract 5b – WAS Thickening

All electrical loads associated with the thickening process will be provided from 600V distribution installed under Contract 2a in the Energy Center. Additional 600V MCC sections will be added as required.

17.6 Codes and Standards

The electrical design will conform to the following latest codes and standards:

Ontario Electrical Safety Code – (2009)



Ontario Building Code – (2010) National Fire Code of Canada Applicable CSA Standards Electrical Safety Authority-(ESA) Requirements of local Hydro Utility-(Kitchener Wilmot Hydro)

17.7 Demand Summary

17.7.1 Connected and Peak Loads

Table 120 presents a preliminary listing of the electrical loads at the Kitchener WWTP with this upgrade project. New loads include additional aeration blowers to be installed in the new blower building to service Plant 3 and 4, new headworks and thickening facilities, including an adjacent gas cleaning and cogeneration facility, a new tertiary treatment facility and digester upgrades. Table 120 Preliminary Electrical Load at the Kitchener WWTP with Planned Upgrades

Process Area (kW) Connected Load (kW) Peak Load (kW) Maintenance Building (Existing Administration Building) 69 52

Existing Digester Building (with Upgrades) 303 159

New Headworks Building 245 220

Existing Pump Sludge Gallery 83 55

New Administration Building 50 50

Plant 2/3 Aeration Blower Building 2,914 2,465

UV Disinfection 722 504

New Plant 2,3,4 RAS/WAS Pumps 578 444

New Tertiary Treatment and Intermediate Pumping 1,010 753

Effluent Pumping Station 1,162 687

New Thickening Building and Gas Boiler/Cleaning 194 139

Misc. Lighting and HVAC (approx. 5%) 352 261

Total 7,682 5,786

17.7.2 Emergency Power Design Loads

The critical process loads that will operate under emergency conditions are identified in Table 121. The emergency load requirements were developed based on providing for 50% of the average design load for all processes and buildings, with the exception of essential processes (Headworks, UV disinfection and Effluent Pumping) and life safety in occupied areas (Administration building, Maintenance building, miscellaneous lights and HVAC equipment), which would be provided for 100%.



Table 121 Estimated Standby Power Loads

Process Area (kW) Peak Load

(kW) Emergency Load (kW)

Comment

Maintenance Building (Existing Administration Building) 52 52 Emergency loading is 100% of peak

New Digested Sludge Pumps (in Ex. Admin Building) - - Loads accounted for in New Digester Building and Boilers

New Digester Building & Boilers 720 360 Emergency loading is 50% of peak

New Headworks Building 220 220 Emergency loading is 100% of peak

Existing Pump Sludge Gallery 182 63 Emergency loading is 50% of peak

New Administration Building 50 50 Emergency loading is 100% of peak

Plant 2,3,4 Aeration Blower Building 2,465 725 Average load is 50% of peak. Emergency loading is 2 blowers per blower train (total 4) @ 75% of Peak Load

UV Disinfection 504 504 Emergency loading is 100% of peak

New Plant 2,3,4 RAS/WAS Pumps 354 223 100% of Average load.

New Tertiary Treatment 247 191 100% of Average load.

Effluent Pumping Station 687 687 Emergency loading is 100% of peak

New Thickening Building 251 104 Emergency loading is 50% of peak

Misc. Lighting and HVAC (approx. 5%) 261 261 Emergency loading is 100% of peak

Total 5,993 3,394

17.8 Standby Power

The Kitchener WWTP upgrades project will include upgrades to the emergency power system to meet the Region’s requirements. The design concept is based on providing emergency power that is integrated into the new 13.8 kV Energy Center distribution switchgear so that all of the Kitchener WWTP loads will have access to emergency power. The use of 13.8 kV emergency power will eliminate the need for any intermediate transformation. The Energy Center switchgear will be capable of providing both normal and emergency power via that same 13.8 kV distribution system to all plant processes. The main Utility 13.8 kV service feeders and generator breaker will be located in a common switchgear arrangement, which allows for the implementation of utility parallel generation, including co-generation, peak shaving and base loading operations. The use of utility paralleling technology provides a synchronized (bumpless) transfer from emergency power to normal power, once the utility power is restored after a power outage. This eliminates the second power interruption to process systems when returning to normal power. A synchronized retransfer will soft load the plant equipment from the generator to the utility in a controlled manner. The combined emergency power generation equipment capacity will be synchronized to service all site loads. Plant process SCADA control may be utilized to prioritize which process systems receive power, within the capacity of the power generation equipment. Two (2) 1,750 kW prime power rated emergency diesel generators will meet emergency power needs for the Kitchener WWTP. Diesel powered generators are preferred over natural gas units for wastewater process loads due to their unparalleled ability to handle large in-rush and transient loads associated with starting large motor loads, such as pumps, as required during a power failure.

17.9 Cogeneration Facility

A co-generation system will be installed in the future. The co-generation system will consist of a reciprocating generator that will operate based on Digester – Biogas. The generator will be located in near the Digester complex. Once the cogeneration system is installed, it will be necessary to integrate it into the Kitchener WWTP electrical distribution system. The total load at the WWTP will increase significantly as a result of all the Plant upgrades. Once



the cogeneration system is integrated into the plant distribution system, all of the power produced by the generator will be consumed by the local distribution system loads. The operation of the co-generation system will need to be coordinated with the operation of the new electrical distribution system, including the operation of new emergency power generation system. The co-generation system will be based on 13.8 kV such that it may be directly connected to the Energy Center 13.8 kV distribution switchgear.

17.10 Construction Contract Considerations


The existing 400 amp, 600 V power feed from the existing outdoor 600V switchgear to the administration building is undersized to accommodate the 150HP transfer pumps.

A 600Amp, 600V power feed from a spare 600Amp breaker located in the existing outdoor 600V SWGR will provide an interim solution.

A new MCC will be provided in the administration building to suit new pump loads and existing administration building loads

The existing natural gas powered 150kW generator will be retained; however, the existing 400 amp transfer switch will have to replaced with a new 600 amp transfer switch.

o Once the new Energy Centre is complete, the 150 kW generator and 600 amp transfer switch will be removed.

Given that existing boiler room being fed from the administration building and on emergency power the existing boiler room should remain fed from the new MCC in the administration building.


The electrical room in the existing Digester Building is small and not suitable for accommodating the installation of new starters for new process equipment. The MCC in the electrical room is the existing MCC-7 and is fed at 400 amps, which is undersized to suit the new loads.

In order to provide one point of electrical isolation for the digester facility, a new electrical room will be constructed to house a new MCC and required starters. The MCC serving the digester facility will be fed from the new energy center.

Existing MCC-7 will ultimately be fed from the new Energy Center and not the existing outdoor 600V SWGR Once the Energy Center is constructed, interim power feed to the existing administration building will be

replaced with a power feed from the energy centre.


The new Energy Centre will contain new 13.8 kV Switchgear which will be fed from the outdoor 13.8 KV Switchgear designated as KITSWG01. The KITSWG01 serves as the utility service entrance for two (2) utility feeders as well as the point of Utility metering. The KITSWG01 also serves as the point of 13.8 kV distribution to the blower building secondary switchgear for Plant 2 designated as KITSWG02 to suit upgrades. Under the scope of Contract 2a, the 13.8 kV power feed to KITSWG02 will be re-routed to the new 13.8kV SWGR being installed in the Energy Center.

The new 13.8 kV SWGR will be designed as a secondary selective SWGR with tie breaker and will serve as the point of 13.8 kV distribution for the entire Kitchener WWTP plant as well an emergency bus for integration of two (2) 1500 kW emergency power generators.

The new Energy Center electrical room will house the following electrical equipment: new 13.8kV SWGR., 2-1500 kVA , 13.8 kV/600 V dry type transformers ,600 V motor control center to suit the Energy Centre and sludge thickening equipment loads and starters and distribution panels.

To accommodate the Thickening Building being constructed under Contract 5b, the dry type transformers and MCCs have being sized to include all future loads associated with the sludge thickening process. The MCCs



installed under Contract 2a will be expandable to add required MCC cubicles to accommodate equipment loads installed under Contract 5b at a future date.


The design of the new Headworks Building will require two (2) new outdoor liquid filled 500 kVA, 13.8 kV/600 V transformers.

The new transformers will be fed at 13.8 kV from the new 13.8 kV switchgear located in the new Energy Center. The MCC in the Headworks Building will be designed as secondary selective and will be fed from separate

buses on the 13.8 kV SWGR in the Energy Center. Given the close proximity of the new administration building to the Headworks, it will provide power feed to the

new Administration Building from the Headworks MCC. All power distribution and lighting will be constructed to suit Class 1, Div1, wiring standards as defined by the

Ontario Hydro Electrical Safety Code.

17.10.5 Contract 4 – Plant 2 Blower Building

The existing outdoor 600 V switchgear designated as KITSWG02 will be expanded to add a second main breaker and tie breaker to suit providing power distribution to suit blower building upgrades and Plant 2,3 and 4 RAS/WAS upgrades

The existing 13.8 kV feeder from 13.8 kV SWGR KITSWG01 will be re-rerouted to the new 13.8 kV SWGR located in the new Energy Center.

A new 13.8 kV feeder will be provided from the new 13.8kV SWGR located in the energy center to suit providing power supply to a second 3000 kVA, 13.8 kV, 600V transformer at KITSWG02.

The outdoor 600 V KITSWG02 will be retrofit to provide power feed to a new 600 V MCC located in the blower building electrical room. The new MCC will be designed to suit blower process loads being added.

The outdoor 600 V KITSWG02 will be retrofit to provide two (2) 600 V power feeds to the MCC located in Plant 3 RAS/WAS pumping station electrical room

17.10.6 Contract 4 – Plant 3 and 4 RAS/WAS Pumping Station and Secondary Clarifiers

The outdoor 600V KITSWG02 will be retrofit to provide two (2) 600V power feds to the MCC located in the Plant 3 RAS/WAS electrical Room.

The Plant 4 RAS/WAS MCC will be fed at 600V from the Plant 3 RAS/WAS MCC The four (4) new secondary clarifiers and gate valves associated with the Plant 3 RAS/WAS pumping station will

be fed from the Plant 3 RAS/WAS pumping station MCC.

17.10.7 Contract 4 – Plant 2 RAS/WAS Pumping Station

The Plant 2 RAS/WAS pumping station MCC will be fed from the Plant 3 RAS/WAS pumping station MCC The four (4) secondary clarifiers and gate valves associated with the Plant 2 RAS/WAS pumping station will be

fed from the Plant 2 RAS/WAS MCC.


The sludge thickening process equipment will be serviced electrically from the MCCs and electrical distribution panels installed under Contract 2a in the Energy Center electrical room.

The existing 600 V MCC sections in the electrical room will be expanded to include starters and power distribution to suit the sludge thickening process loads.



17.11 Lighting Systems

Lighting system designs will be based on the use of energy efficient T5 fluorescents or LED lighting with occupancy sensors and automated controls where applicable. A multi tiered lighting control approach will be provided as follows: Tier 1: Continuous lighting - applicable to dark locations with minimal lighting for safety (e.g., tunnels and unlit

locations, dark entry/exit points, and dark stairwells) Tier 2: General lighting- Photocell and /or occupancy controlled lighting for general (non task) purposes with the

intent to enhance Tier 1 lighting based on occupancy Tier 3: Task lighting specific to work areas with occupancy and electronic time switch control with the intent that

mobile lighting will be used to further enhance task lighting design, (e.g., specific maintenance and/or service task lighting)

Outdoor lighting will be provided around perimeter of the new aeration tanks and secondary clarifiers.



18. Common Elements 18.1 Hydraulics

18.1.1 Hydraulic Profile

An overall hydraulic profile has been developed for the Kitchener WWTP. Available information included upgrades to the new Headworks Building, Plant 3 and 4 upgrades, the hydraulic profile developed by the current designer of the Plant 2 improvements, UV disinfection system and effluent pump station. The plant treatment processes were divided into several main sections, and hydraulic profiles of each section were developed by calculating the headlosses upstream of specific boundary conditions. The hydraulic profile is divided into two (2) independent, but inter-related trains: one for Plant 3 and 4 and one for Plant 2. Hydraulic calculations are presented in Appendix O. The hydraulic profile for Plants 3 and 4 is presented in Appendix A (000-D005). The control points are the primary clarifier weir (284.91 m) and the effluent weir of the UV disinfection system (approx. 279.5 m). Since Plants 3 and 4 represents new works, there is the opportunity to size channels/pipes and set elevations to work within the available hydraulic profile limits. The available Plant 3 and 4 hydraulic head (5.4 m) is more than sufficient to accommodate all process elements including tertiary filtration employing disk filter technology. The hydraulic profile for Plant 2 is presented in Appendix A (000-D005). The hydraulic profile for Plant 2 is more complicated than that of Plants 3 and 4. The UV disinfection and EPS projects did not anticipate the hydraulic requirements for tertiary filtration. As a result, the available head between the effluent weir from secondary clarifiers (281.69 m) and the UV disinfection system (approx. 279.5 m) is very limited. Currently, the effluent from secondary clarifier No. 1 flows into the effluent chamber from secondary clarifier No. 2. These combined streams combine with the effluent from secondary Clarifier No. 3 in Chamber 3. Effluent from secondary clarifier No. 4 also discharges to Chamber 3. The combined flow from all four secondary clarifiers is routed to the UV disinfection building, and to the Tertiary Treatment building in the future. This flow scheme results in significant and requires piping modification for flow optimization. The modifications involve providing a new secondary effluent channel for two (2) of the Plant 2 secondary clarifiers. The combined discharge from secondary clarifiers No.1 and 2 would be diverted to the large Plant 3 and 4 effluent conduit that passes to the north of the Plant 2 secondary clarifiers. In addition, the Plant 2 secondary clarifier launders would be raised by 200 mm. This modification can be easily accommodated during the planned replacement of Plant 2 secondary clarifier mechanisms. Due to the head differential between the existing aeration tanks and secondary clarifiers, the increase in weir elevation will have minimal impact on internal Plant 2 hydraulics. Upon completion, the above modifications will significantly reduce the overall between the Plant 2 secondary clarifiers and Tertiary Treatment building.

18.1.2 Tertiary Filtration System Hydraulics

System hydraulics were modelled for the following flow conditions: Average flow of 122.7 MLD Peak instantaneous flow of 430 MLD based on the following flow distribution:

Plant 2 effluent flow of 120 MLD Plant 3 and 4 effluent flow of 310 MLD Flow into tertiary treatment of 318 MLD Tertiary bypass flow of 112 MLD



Detailed hydraulic calculations are included in Appendix O. It is important to note that the two (2) weir assemblies used on the Aquadisk® disk filter arrangement contribute to a total system higher than would be provided by other disk filter equipment. However, this configuration will help to maintain even flow distribution. Basing the design on Aquadisk® ensures that a conservative approach to the system hydraulics has been evaluated. To accommodate the associated with the new tertiary filtration facility based on Aquadisk®, two modifications are recommended for Plant 2 secondary clarification, as follows: Provide a new secondary effluent channel for two of the Plant 2 secondary clarifiers to reduce peak flow in the

Plant 2 secondary effluent channel Raise the Plant 2 secondary clarifier launder by approximately 200 mm, which can be easily accommodated

during the planned replacement of Plant 2 secondary clarifier mechanisms. Due to the head differential between the existing aeration tanks and secondary clarifiers, the increase in weir elevation will have minimal impact on internal Plant 2 hydraulics.

Overall, these modifications allow the new tertiary filtration system to accommodate design peak flow events while maintaining approximately 200 mm freeboard at the Plant 2 secondary clarifiers. These modifications may or may not be required with other equipment technology. Plant 2 modifications should be completed before or during the construction of the tertiary treatment facility to provide adequate hydraulic buffering capacity.

18.2 Civil/Site Design

18.2.1 Overall Layout

The overall layout of the site will maintain the existing look of the site with driveways/roads surrounding the existing and new tanks and buildings. The major change to the site will be the decommissioning of the existing lagoons for the installation of new building and process centres. The Site Design has been developed to the conceptual level pending finalization of building/tank layouts and elevations. The general approaches to site development were reviewed with the GRCA at a meeting dated February 24, 2012.

18.2.2 Erosion Control

Erosion control will be required during construction to mitigate impacts to the river and existing naturalized features of the site. Methods such as silt fencing, straw and rock check dams, catch basin protection, erosion control mats and hydro seeding will be implemented where applicable. These erosion control items will be decommissioned once topsoil areas are grassed or naturalized, storm sewer outlets have been stabilized via rip-rap protection or other forms of energy dissipation, and overall construction is complete.

18.2.3 Roads and Access

Roads will be designed to function like the existing road network. New roads will have a similar cross-section to the existing roads. The existing driveway access from Mill Park Drive is not suitable for use during construction and will be upgraded and rebuilt to improve safety, traffic flow and durability. The lower portion of the driveway will be bypassed via a newly constructed road while modifications to the vertical alignment of the driveway near the new overhead effluent channel are completed. A new parking area around the new administration building will service the site. The roadway system will be laid out in a manner that allows for future expansion of the plant.

18.2.4 Flood Plain Management and Mitigation

Most of the site is located in the Grand River floodplain. The mean elevation of the site is at approximately 281.50 m. The Regional flood elevation is 283.63 m. A “design” flood elevation of 282.37 m has been used as per the agreement with the GRCA made during the ongoing Plant 2 upgrades/UV disinfection and identified in the Site Wide



Facility Plan Report. All new buildings will be designed to be above the design flood elevation. Where feasible, buildings will be designed to be above the Regional flood elevation. Roads will be designed so that flooding of the road during the “design” flood elevation will be less than 0.30 m, where feasible. Existing points of discharge and flow patterns will be followed as closely as possible.

18.2.5 Stormwater Management

A piped storm drainage network will be sized for the five-year minor storm event. The major storm event flow will be conveyed via overland flow. The site will be designed for quality control exclusively. A treatment train approach will be used in the newly developed/redesigned areas. Due to the proximity to the Grand River, quantity control of stormwater is not required, as agreed with the Grand River Conservation Authority. With the site being located so close to the river and the high ground water table, infiltration is not a practical part of the stormwater management strategy. Grassed swales for runoff conveyance will be used as opposed to gutter or piped flow where possible to provide pre-treatment, delay the time of concentration, and lower runoff velocities to reduce erosion potential.

18.3 Structural and Architectural Design

18.3.1 Codes and Standards

All codes and standards applicable to the design of architectural and structural components of the Kitchener WWTP Upgrades were considered. Local codes will govern in cases of conflicting requirements. The codes and standards applicable to the Kitchener WWTP upgrades are as follows:

Codes o OBC 2006 o Region of Waterloo’s Accessibility Design Guidelines o NFPA 820 Standard for Fire Protection in Wastewater Treatment and Collection Facilities, 2008 Edition o Structural Commentaries to the National Building Code 2005 (Part 4) o City of Kitchener Building Department o MOL Guidelines for Industrial Facilities

Masonry Codes o CSA-S304.1-04(R2010) “Design of Masonry Structures” o CSA-A371-04(R2009) “Masonry Construction for Buildings” o CSA-A370-04(R2009) “Masonry Connectors”

Concrete Codes o CSA A23.1-09/A23.2-09 Concrete Materials and Methods of Concrete Construction/Methods of Test for

Concrete o CSA A23.3-04 (R-2010) Design of Concrete Structures o ACI 350M-06 – Code requirements for Environmental Engineering Concrete Structures

Steel Codes o CAN/CSA-S16.09Design of Steel Structures

Foundation Codes o “Canadian Foundation Engineering Manual”, 2007 by Canadian Geotechnical Society Publication

Wood Codes o CAN/CSA-O86-01 CONSOLIDATION (2006), “Engineering Design in Wood”

Aluminum Codes o CAN/CSA-S157-05/ S157.1-05 “Strength Design in Aluminum”.



18.3.2 Preliminary Ontario Building Code Review

The relevant OBC 2006 Part 3 Building Code requirements for the Headworks Building, Energy Centre and Thickening Building, RAS/WAS Pumping Stations, Digester Complex and Tertiary Treatment Building (Group F-3 [Low Hazard Industrial] 3.2.2.76 up to four (4) storeys) are as follows: Permitted to be non-combustible or combustible construction Floor assemblies are to be fire separations; if of combustible construction, a fire resistance rating (FRR) of 45

min is required Mezzanines, if of combustible construction, will have an FRR of 45 min Roof assemblies, if of combustible construction, will have an FRR of 45 min Load bearing walls, columns and arches will have a FRR no less than the supported assembly Spatial separations:

o 100% unprotected openings, if limiting distance is greater than nine (9) metres Underground walkways

o Will be separated from each building with one (1) hr FRR and be of non-combustible construction o Maximum travel distance between exits is 67 m

Fire Fighting o Fire alarm system required (2 stage) with annunciator panel o Fire fighting entrance and access route to be provided o Standpipe system required if a hydrant is more than 45 m from each building

Exits o Minimum of 2 exits required o Stairwells are to have a FRR of 45 min o Maximum travel distance to each exit 30 m

Washrooms o None required as per 3.7.4.1(3) because buildings are not normally occupied by persons and

washrooms in the administration and maintenance buildings can be used when needed Barrier-Free

o Section 3.8 not applicable as per 3.8.1.1(c) because buildings will not be occupied on a full-time basis

The relevant OBC 2006 Part 3 Building Code requirements for the Administration Building (Group D [Office] 3.2.2.56 up to 2 Storeys, Sprinklered) are as follows: If two (2) storeys, the building area must not be more than 2,400m2; the design is within this limit Permitted to be of combustible or non-combustible construction used singly or in combination Floor assemblies are fire separations; if of combustible construction, must have a 45 min FRR Load bearing walls, columns and arches are to be of non-combustible construction and have a 45 min FRR (only

if supporting rated construction) Spatial Separations

o 100% unprotected openings if limiting distance is greater than 9 m Under Ground Walkways

o Will be separated from each building with one (1) hr. FRR and be of non-combustible construction o Maximum travel distance between exits is 67 m

Fire Fighting o Fire alarm system is not required o Standpipe system is required if a hydrant is more than 45 m from the building

Exits o Minimum of 2 exits required



o Stairwells to have one (1) h FRR o Maximum travel distance to each exit is 40 m

Washrooms o Based on occupant load; three (3) fixtures per gender

Barrier-Free o Barrier-free design through-out that conforms to the OBC and Region of Waterloo’s Accessibility Design

Guidelines Parking Requirements

o Zoning P3, City of Kitchener requires one (1) space for every 28 m2 of floor area in an office building. o Based on design occupancy for administration building, 50 spaces are needed including two (2) barrier-

free space

18.3.3 LEED Design Features

LEED certification will not be pursued for the Headworks Building, Thickening, RAS/WAS Pumping Stations and Tertiary Treatment buildings; however, where prudent sustainable principles will be implemented into their design. Areas of focus include: Energy efficiency Use of durable, regional, recycled and low VOC materials Natural day-lighting Building orientation and protection from the elements Rainwater harvesting Incorporating native and low maintenance landscaping Use of shade and light-coloured/high-albedo materials to reduce heat islands

The incorporation of these principles throughout the design will create efficiencies throughout the plant, improve building longevity and lower maintenance and operating costs. LEED Silver certification will be pursued for the new administration building, as discussed in Section 14.4.

18.3.4 Architectural Theme

The design of the buildings at the Kitchener WWTP will be developed to invoke a sense of cohesion to the complex. By using contemporary materials and finishes to create a fresh and modern look coupled with the application of sustainable technologies, we will design an efficient, practical and functional facility for all users. An architectural theme composed of sleek lines, tinted glass, stone veneer, metal siding and prefinished composite aluminum and wood panels will define the overall design language and style. The intent is to create spaces that meet the needs of a modern wastewater treatment facility while incorporating natural day lighting, views, controllability of spaces and ergonomics for the occupants; a building that is true to the design principles of a sustainable LEED building.

18.4 Structural and Geotechnical Aspects

18.4.1 Foundation Considerations

18.4.1.1 Soil Conditions

The draft geotechnical report (SPL, 2012) indicates the new tanks and buildings can be founded on engineered fill. Considering the existing WWTP layout and process requirement, some existing structures need to be removed, some need to be relocated, and some areas on site need to be cleaned and backfilled. Therefore, all new structures



and tanks will be bearing on the engineered fills. However, some of the ancillary structures will be supported on the caissons either because of the construction sequences or the characters of the structure itself. All new buildings and structures will be designed to resist uplift pressures, and water pressured due to a flood condition. A design flood level of 282.37 m has been negotiated with the GRCA, and will be the minimum design level for all buildings and structures. The Regional flood level is 283.63 m, which is higher than the design flood level. As a consequence, all structures that have walls above the design flood level will be capable of withstanding flood to the top of the wall up to elevation 283.63 m. The design will include hold down anchors to provide stability and tank and basement walls that can resist the water pressure. As designed and estimated, the soil anchoring system, Micro-piles and jacking pads will be used for all the tanks and buildings with basement to resist uplift from the flooded water and the perimeter drain will be provided around all walls below grade. For soil anchors, 48 KPa bond value for compact to dense soil and minimum of four (4) meters long bonded length will be used, as recommended by SPL. Two full-scale pull-off tests to 200% of designed capacity will be conducted prior to the full production of the piles at the areas selected by the Engineer, and each pile will be tested to 133% of designed capacity during the pile installation. The settlement of the structures, whether the structures are supported on individual strip or spread footings or rest on raft (e.g. tank), will be within tolerable limits. The lagoon areas will be decommissioned, and the expected construction elevation after this process is 277.00 m. The tanks that are planned for the lagoon area require further excavation to elevation 275.85 m. It is expected that competent native soil will be found at this elevation. In the event that there are soft areas in these layers, the use of the soil anchors as compression piles will be investigated. In the areas of the current lagoons, the geotechnical information for preliminary design has been interpolated from the boreholes drilled along the berm locations. During detailed design, the lagoons are expected to be accessible for a second round of geotechnical investigation. This investigation will be used to confirm and supplement the findings of the investigation by SPL Consultants. The bearing elevation of all the buildings will be set to be a minimum of 1.2 mbg to provide frost protection. In many cases, this elevation is in fill or loose soils. In these areas, engineered fill with strip foundations or piles will be used. SPL recommended that all footings supported by engineered fill will have a bearing capacity of 200KPa at serviceability limit states and 300 KPa at the ultimate limit states. Engineered fill consists of the approved Granular B material compacted to 100% of SPMDD throughout. The cast-in-place concrete piles and soil anchors will be used as required and the bearing resistance will be verified by the full scale of load tests prior to the productions.

18.4.1.2 Design and Construction Considerations

Foundation types, details, allowable pressure at founding level, frost penetration depth, design groundwater level, seismic design parameters and lateral earth pressure coefficients will be based on recommendations made by the geotechnical consultant for the project. Water retaining tank will be designed for the following loading conditions: Tank structures filled to normal operating level, no earth backfill Tank structures empty, earth backfill, groundwater at normal level Tank structure empty, earth backfill, groundwater at flood level to develop maximum stress, (not checked for

crack control) Any combination of tank structures empty or full to develop maximum stress



Seismic loading, tank structures filled to normal operating level, earth backfill, to develop maximum stress Truck surcharge adjacent to each structure in combination with other loading cases except floor and earthquake.

18.4.2 Design Loads

Table 122 presents building code climatic design data. Table 122 Building Code Climatic Design Data

Location Unit Kitchener Value

Ground snow load (1/50) yrs Ss 2.0 kN/m2

Associated rain load (1/50 yrs) Sr 0.4 kN/m2

Snow Load Importance factor Is (ULS) Is (SLS)

1.25 0.9

Reference Hourly Wind pressure (1/50 yrs) q 0.37 kN/m2

Wind Load Importance factor Iw (ULS) Iw (SLS)

1.25 0.75

Wind internal pressures Cpi (internal pressure coefficient) Category 3

One day rainfall (1/50 yrs) 119 mm

Seismic data PGA (peak ground acceleration) 0.110

5% damped spectral response acceleration values (2% Probability of exceedance in 50 years)

Sa(0.2) 0.19

Sa(0.5) 0.096

Sa(1.0) 0.048

Sa(2.0) 0.013

Seismic site response Soil Class C

Seismic Importance factor Ie (ULS) Ie (SLS)

1.5 As per code requirements

Unit self weights based on industry-accepted values, applicable to materials suggested for use in the new structures are presented in Table 123. Table 123 Unit Self Weight

Material Unit Self Weight

Reinforced concrete and pre-cast concrete 24 kN/m3

Structural steel 77 kN/m3

Aluminium 27 kN/m3

Aluminium checkered plate, 6 mm thick 0.20 kPa

Aluminium grating Manufacturer’s literature

Metal roofing Manufacturer’s literature

Metal siding Manufacturer’s literature

Protected membrane roofing system 0.20 kPa

Equipment and piping Manufacturer’s literature

Design live loads, based on anticipated use and occupancy, applicable to the new structures are presented in Table 124.



Table 124 Design Live Loads Anticipated Use Design Live Load

Construction 2.4 kPa

Building roof (minimum, if greater than wind or snow loads) 1.0 kPa or 1.3 KN concentrated load

Buried tank roof (excluding earth cover) and truck surcharge adjacent to buried structures 12.0 kPa or wheel loads as per CSA - S 6

Electrical control rooms (or weight of equipment) 6.0 kPa

General personnel areas, and corridors 4.8 kPa

Office and laboratory 4.8 kPa

Stairs 4.8 kPa

Service platforms, walkways, and ramps 4.8 kPa

Mechanical equipment rooms (or weight of equipment) 12.0 kPa

Loading bay 12 kPa or wheel loads as per CSA S 6

Storage areas 12.0 kPa

Unit weights of materials, used to determine lateral pressures, for design of the new structures are presented in Table 125. Table 125 Unit Weight of Materials

Material Unit Weight

Snow 3.00 kN/m3 Water 9.81 kN/m3 Earth backfill 21.0 kN/m3 Monorail beams will be provided where required. Monorail beams will be designed as per the governing building code requirements for crane supporting structures.

18.4.2.1.1 Deflections

Live load deflection, expressed as a ratio of the clear span, of various components of the new structures will be restricted to the limits presented in Table 126. Table 126 Live Load Deflection Limits

Component Live Load Deflection

Concrete roof framing 1/240 Concrete floor framing 1/360 Steel framing Similar to concrete framing Checkered plate l/360; maximum 6 mm Open grating l/360; maximum 6 mm Beams supporting masonry 1/600 Monorail and crane beams l/800 vertically and horizontally

18.4.2.1.2 Vibration

Resonance of pumps, gen-sets, and similar vibration producing equipment will be checked against the natural frequency of the supporting concrete slabs. Natural frequency of suspended concrete slabs subjected to vibration will be designed such that the natural frequency of the slab with respect to the vibration from the equipment will be outside of the following limits: Less than one-half Greater than one and one-half



18.4.3 Structural Materials

An overview of structural materials used in the Preliminary Design is presented in Table 127. Table 127 Overview of Structural Materials

Tanks, Basements, and underground galleries High performance low shrinkage concrete 30MPa

Superstructures Load bearing concrete block; concrete frame or Structural steel Roof Decks Precast concrete Stairs FRP; Aluminium or pre-cast concrete Grating Aluminium ; FRP; or Stainless Steel Hand rail Aluminium ; FRP; Galvanized Steel or Stainless Steel Misc steel submerged Stainless Steel Type 316, Misc steel exposed Aluminium ; Galvanized Steel or Stainless Steel Misc steel interior Galvanized carbon steel Hatches Bilco or Uma


18.5.1 Design Criteria

18.5.1.1 Codes and Standards

The following, but not limited to, codes and standards have been applied to this Preliminary Design: Ontario Building Code (OBC) Ontario Fire Code (OFC) Ontario Plumbing Code (OPC) and National Plumbing Code (NPC) NFPA 820, “Standard for Fire Protection in Wastewater Treatment and Collection Facilities” MOE Design Guidelines for Sewage Works ASHRAE Standard 62- “Ventilation for Acceptable Indoor Air Quality” NFPA Standards stipulated within OBC Natural Gas Installation Code National Energy Code/American Society of Heating, Refrigeration and Air-Conditioning Engineers (ASHRAE)

Standard 90.1 American Society of Heating, Refrigeration and Air-Conditioning Engineers (ASHRAE) Standards, Handbooks

and Periodicals American Society of Mechanical Engineers (ASME) Sheet Metal and Air-Conditioning Contractors Association (SMACNA) Standards and Guidelines Air Moving and Conditioning Association (AMCA) Local bylaws

ASHRAE 62 compliance:

The AHU serving the screen area are providing 100% outdoor air to the area served, to conform to the requirements of NFPA 820, “Standard for Fire Protection in Wastewater Treatment and Collection Facilities”, which takes precedence over ASHRAE 62 in the design of Wastewater Treatment and Collection Facilities. Since NFPA 820 dictates ventilation quantities required to mitigate the effects of explosive gases and/or odours, the air quantities that result from it are, in this case, higher than those required by ASHRAE 62.

Air change rates for area other than screen area which are not classified will be based on heat dissipation from equipment, good engineering practices and past experience, which takes precedence over ASHRAE- 62 in the design of Wastewater Treatment and Collection Facilities



ASHRAE 90.1 compliance:

It is our understanding that WWTPs are exempt under Article 12.2.1.1-5-(b) of the OBC 2006 as they fall under the category of an Industrial Processing plant.

It is our further understanding, based on a discussion with staff at the OBC, that under the Supplementary Standards to the OBC 2006, SB-10, Article 1.2.1.1-5-Table 1.2.1.1, under Group F, Division 3 (Buildings) WWTPs fall under the category of Pumping Stations and are therefore exempt from the requirements ASHRAE 90.1.

Notwithstanding the above, we recognize that energy efficiency and system efficiencies are of paramount importance to the Region and AECOM will implement best design practices, as applicable, to maximize efficiency and minimize energy consumption. For additional details refer to section “Energy Conserving Enhancements”.

18.5.1.2 Outdoor Design Criteria

The following climatic data will be used for the design: Winter: -21 °C (1%) Summer: 29 °C Dry Bulb/23 °C Wet Bulb Heating Degree Days Below 18 °C: 4250

18.5.1.3 Indoor Design Criteria

The typical indoor design conditions used in this design are presented in Table 128.

Table 128 Indoor Design Criteria Areas Criteria

Mechanical Rooms 5.5 °C above outdoor temperature (summer) / 18 °C (winter)

Electrical Rooms 27 °C (summer) / 18 °C (winter)

Process Areas 5.5 °C above outdoor temperature (summer) / 5 - 10 °C unoccupied mode and 18 °C for occupied mode (winter)

Control Rooms / Administration offices occupied on continuous basis

24 °C (summer) 50% RH / 22 °C (winter)

Note: The above design parameters might have a deviation of about +/- 10%, dependent on space and application.

18.5.2 Energy Code Compliance and Building Insulation

The envelope requirements will meet or exceed the Minimum Thermal Resistance of Building Assemblies, as stipulated in OBC 2006, section 12.



NFPA 820 defines the minimum ventilation criteria for protection against fire and explosion of WWTPs. These recommended rates will largely define the ventilation rates to be used in the process spaces. When odour control or space temperature control is the objective of design, air change rates might increase beyond the levels prescribed in NFPA 820. These air change rates will be based on good engineering practice and past experience and in keeping with principles of energy efficiency. The HVAC design criteria for various areas are as follows:



All non-process areas will be ventilated in accordance with the applicable codes and the recommendations of ASHRAE Standard 62

All process buildings will be ventilated in accordance with the recommendations of NFPA 820 as well as to relieve heat build-up from process equipment.

Where ventilation is mandated by NFPA 820 to minimize fire and explosion hazards, both supply and exhaust fan will be provided unless otherwise permitted by NFPA 820

Ventilation equipments will be provided with flow sensors, input from gas detection systems, alarms, and dual power supply sources, as per NFPA 820 requirements. Alarm status can be initiated at various locations, including local HVAC control panel and, if applicable, in the plant wide control SCADA/PCS system. In addition, the ventilation equipments will provide dual ventilation rates to allow energy conservation as per NFPA 820 Chapter 9, for detail see section “Energy-Conserving Enhancements”

18.5.3.2 Ventilation Rates

The ventilation rates for the various areas are presented in the process area specific Building Mechanical Services sections.

18.5.3.3 Redundancy

In general, for classified process areas the HVAC system will consist of one (1) unit with two (2) supply and two (2) exhaust fans, each fan with 50-percent of the required total flow rate. For unclassified process areas and the rest of the buildings, the HVAC system will consist of one (1) unit incorporating two (2) supply and two (2) exhaust fans, each fan capable of supplying 50% of the required total flow rate.

18.5.3.4 Heat Relief System

Heat relief ventilation will be provided for areas such as blower rooms. Systems serving these areas will feature equipment equipped with VFDs to enhance energy conservation and reduce maintenance cost (e.g., increase filter life span).

18.5.3.5 Cooling System

The electrical and control rooms will be provided with dedicated mechanical cooling systems (i.e., DX split unit).

18.5.3.6 Outdoor Air Filtration Criteria

Filters will be provided with differential pressure gauges and switches that will automatically alert plant personnel when filters require replacement. The outside air filtration presented in Table 129. Table 129 Outdoor Air Filtration Criteria

Area Outdoor Air Filtration Criteria

Control room / Administration offices occupied on continuous basis Rated MERV14 (ASHRAE 52.2) final filter and MERV7 (ASHRAE 52.2-2007) pre-filter.

Electrical Rooms Rated MERV7 (ASHRAE 52.2)

Process Areas Rated MERV14 (ASHRAE 52.2) final filter and MERV7 (ASHRAE 52.2-2007) pre-filter.

18.5.3.7 Space Pressurization Control Criteria

HVAC systems have been designed to control building pressurization according to the space pressurization criteria presented in Table 130.



Table 130 Space Pressurization Controls Criteria Area Space Pressurization Control Criteria

Occupied Non-process Areas Maintained at +25 Pa relative to ambient

Electrical Room Maintained at +25 Pa relative to ambient

Process Areas As per NFPA 820 requirements (positive or negative dependent on classification)

18.5.3.8 Ductwork Criteria

SMACNA standards for duct construction will be adhered to. This standard stipulates duct thickness based on size and pressure ratings. In addition, ductwork will comply with the following: All supply/return ductwork in Control room and electrical room will be galvanized steel All supply/exhaust ductwork in process areas will be aluminum All supply/exhaust ductwork in corrosion areas will be 316 SS All supply/exhaust ductwork in chemical room will be FRP

Round ductwork will be utilized wherever possible. Where rectangular ductwork is required, aspect ratios will be limited to maximum 4:1.

18.5.3.9 Noise Criteria

HVAC equipment serving occupied non-process areas, including control room, will be sized and designed for reducing noise to ASHRAE recommended levels. Maximum noise level is 85 dBA at 1.5 m. The following noise reduction measures will be considered: Acoustic silencers will be provided, as applicable Duct silencers will be utilized where required All AHUs will be provided with internal vibration isolators Noise emanating from AHUs will be less or comparable to process equipment in these spaces

18.5.3.10 Humidity Control Criteria

Air conditioning areas will be designed to maintain approx 50% relative humidity incidentally for control rooms at peak summer design conditions. Humidity throughout of the plant is not monitored or controlled.


The loop for AHUs will incorporate variable speed pumps on a duty/standby basis to match the flow to the glycol demand, glycol recirculation loops will be utilized to ensure the heating coils do not freeze. Horizontal glycol unit heaters and glycol convection heaters will be placed all places including stairs, mechanical rooms and overhead doors to provide supplementary heat for the building. Electrical unit heaters will be used, to avoid hydronic systems, within electrical rooms.



18.5.3.11.1 Heating Source Options

We assume natural gas is available and will be used as a heating source.

18.5.3.11.2 Interface with Odour Control Systems

HVAC system will be interfaced with the OCS to maintain continuously the pressure regime mandated by NFPA 820 requirements. HVAC system and OCS will be interfaced as well with the overhead doors within the truck bay area to prevent odour migration to outdoors by activating high ventilation rate and space pressure control.

18.5.3.12 HVAC Controls

The HVAC systems for new facilities will be controlled by a networked BAS to allow sharing of common point data (i.e. outdoor temperature). This BAS system will integrate multiple building functions including equipment supervision and control, alarm management, energy management, information management, and historical data collection and archiving. The BAS will consist of the following: network controllers, field controllers equipment controllers, terminal controllers, local display devices, and a personal computer based operator workstation. LCPs will include an operator interface for locally changing HVAC control set points and monitoring HVAC control status. Occupied areas in non-process areas will have individual room temperature controllers that maintain space temperature set points. For process areas utilizing space temperature control, AHU operation will be controlled by taking the average of suitably located multiple temperature sensors. Glycol water system will be enabled to meet building heating load during heating season. Freeze states will be provided with most of the AHUs to prevent freeze-up of coils inside the AHUs. If the AHU discharge temperature falls below the minimum discharge air set point, the outside air intake damper will close and the unit will shut down. Each HVAC control panel will be capable of generating a general alarm signal to SCADA in the event that any alarm associated with the corresponding HVAC unit is activated. Selective alarm signals for critical process areas may also be sent to SCADA system from HVAC control systems. Duct smoke detectors will be provided, by Division 16, as per NFPA. In case of any smoke alarm, the corresponding AHU will shut down and alarm will be sent to fire alarm system.

18.5.3.13 Power Supply

Ventilation system serving process areas will receive power from electrical equipment that receives power from a primary power source and that also has the means to accept power from alternate power sources, such as standby generators, portable generators, uninterruptible power supplies, and forth. Automatic or a manual switching to a permanent alternate source of power will also be permitted.




18.5.4.1 Plumbing System Concepts

Water service loop will be required for building potable water. The maximum water pressure from serving potable water system will be 550KPa. Interior hose valves for non-process areas will be based on Plant Standard. Water supply will be WN. Potable water will be metered. All sanitary drains will be drained by gravity to sump pit and sump pump system will be used for pumping to sewer line. Sump pump will be monitored and interfaced with SCADA system. Floor drains and hub drains will have primed P-traps. Water source for trap priming can be either WPS or WN water. Ganged traps will be provided where allowed by codes otherwise individual trap will be provided to floor drains and hub drains. Storm drainage will be designed according to OBC.

18.5.4.2 Insulated Plumbing Piping

The following plumbing piping will be insulated: Cold Potable Water (WPS) Cold Plant Service Water (WN) Potable Hot Water Supply (HWS) Potable Hot Water Return (HWR) Glycol Supply (GLS) Glycol Return (GLR) Tempered water Storm drainage

18.5.4.3 Emergency Safety Equipment

Safety showers and combination safety shower/eyewash units will be provided with tempered water from emergency mixing valves. All combination safety shower/eyewash units located in process areas/chemical room will be provided with a flow switch, light, and alarm bell. The alarm device will be the manufacturer’s standard unit and will to be coordinated with Electrical for power requirements. All combination safety shower/eyewash units located outside will be freeze-resistant units.

18.5.4.4 Cross-Connection Control

Cross-connection control will be provided in accordance with the building code of the local jurisdiction. As an example, reduced pressure backflow preventers will be installed for the following, as a minimum: Main WPS for potable water using will be provided with a reduced pressure valve back-flow prevention assembly Main WN for plant service water using will be provided with a reduced pressure back-flow prevention assembly.



18.5.4.5 Equipment

Plumbing equipment will include water heaters, hot water recirculation pumps. We assume gas will be available for gas fired hot water heater. Hot water heater with storage tank will be provided for tempered water of emergency shower.

18.5.5 Fire Protection

As required by OBC and OFC fire protection system (i.e. standpipe system and fire extinguishers) will be provided throughout, as required.

18.5.6 Energy-Conserving Enhancements

A description of the energy-conserving enhancements applied to the HVAC design is included in the Energy Management Plan. The main objective is to design sustainable HVAC systems in order to minimize the project energy requirements by using the best available energy management technology, including free cooling and free heating, as much as possible. Energy-conserving enhancements for process and non-process area HVAC systems have been considered by using following systems: Each AHU has heat recovery ventilation system which is recovering energy from the exhaust air All fans in AHUs will be equipped with VFDs to give air flow control on the units Glycol recirculation pumps will have VFDs for energy saving purpose Building automation system will be control HVAC system as they designed and need to be operated

Building envelope and systems that minimize building heating, ventilation, and AC requirements will be provided in accordance with best applicable practices. Airflow in all process and non process areas not affected by codes, standards or odour issues will be turned off by timers or the PCS when unoccupied so as to conserve energy. Heat recovery system will be provided to reclaim the heat from classified/unclassified areas. Heat recovery system includes preheat coil, heating piping. It will extract heat from exhaust air and will preheat the fresh air intake. This system will operate in winter to maximize the heat efficiency and energy saving. CFC based refrigerants will not be used in AC system. Ultra high efficiency and high efficiency motors will be provided where applicable.



A new control system will be implemented for the Kitchener WWTP Upgrades process areas. The control system will consist of field devices, new programmable logic controllers (PLCs) for the process areas, network infrastructure and a new SCADA Operator Terminal. The Stage 2 upgrades also includes an expansion of the plant control system



using the existing PLCs and network infrastructure. Refer to the Preliminary Network Architecture Drawings for the Kitchener WWTP Stage 2 expansion project (000-N001 and 000-N002), presented in Appendix A. The instrumentation and controls design will be based on the integration with the plant existing SCADA system and will comply with the current Region of Waterloo’s Design Standards.

18.6.2 Equipment Tagging

The tag names of all new equipment will be provided in accordance with the Region of Waterloo’s Design Standards Section 50008 (Tag Naming).

18.6.3 Process Flow Drawings and Piping and Instrumentation Drawings

The P&IDs are based on the process flow diagrams with the intent of reflecting all equipment and instrumentation associated with the designed processes, the applicable control levels, local controls and hardwired interlocks, and inputs and outputs from the field devices and panels to the corresponding programmable controllers (PLCs), including interface with vendor package panels.

18.6.4 Process Control Narratives

Process control narratives (PCN) have been derived from the process narratives that describe how control logic will function under normal and fault condition for the all applicable process areas. Included in the PCNs are descriptions for operating the system in a range of equipment control modes: Local, Remote Manual, and Remote Auto modes. The PCNs describe the required conditions to operate in each mode and provide details of the control strategies, applicable setpoints, hardwired and software interlocks. The PCNs will be the basis for PLC and SCADA programming.

18.6.5 Equipment Control Modes

Each MCC/LCP related to a field device will be equipped with the selector switch to provide for selection of the operation mode: Local or Remote. In some cases, the Local/Remote selector switch will be located at the field device (e.g., valve actuator). Following the Design Standard requirements, in general, three (3) control modes will be implemented for equipment: LOCAL/MANUAL REMOTE/AUTO (selected at Operator Interfaces) REMOTE/MANUAL (selected at Operator Interfaces)

18.6.5.1 LOCAL/MANUAL

The LOCAL/MANUAL mode of operation of automated equipment is provided for maintenance and trouble-shooting purposes. This mode is also used to normally operate the equipment that does not require higher levels of control. In LOCAL/MANUAL mode, equipment can only be operated using hardwired devices located at the local control stations or MCC, depending upon the configuration. All hardwired safety interlocks, such as overloads and emergency stops, are effective in this mode. The device operates without PLC control, and all software interlocks are bypassed.



18.6.5.2 REMOTE/AUTO

Devices that have selectable modes must be in REMOTE/AUTO mode to be controlled automatically by the SCADA system. In this mode, the PLC controls all aspects of the process, adjusting the process based upon predefined algorithms.

18.6.5.3 REMOTE/MANUAL

In REMOTE/MANUAL mode, the PLC will not make any changes to the process (or related equipment) that is not specifically requested by the operator. From the HMI, the operator will be able to manually control the process (e.g., start and stop equipment and set feed rates).

18.6.6 Interlocks and Resetting

18.6.6.1 Interlocks

Software interlocks are provided on some equipment, through the PLCs. For example, a pump may not be allowed to start until the PLC senses that the pump's discharge valve is open. These interlocks are in effect in both REMOTE/AUTO and REMOTE/MANUAL modes. These PLC interlocks are not in effect when controlling equipment in LOCAL/MANUAL mode. Hardwired interlocks are in effect in all three (3) control modes.

18.6.6.2 Resetting

The PLC locks out some equipment when the PLC determines that it has FAILED. The PLC will not allow the equipment to operate under REMOTE/AUTO mode until the operator executes a RESET at an HMI.

18.6.7 SCADA System Hardware

The SCADA system hardware used for the control system will be in accordance with the Region of Waterloo’s Design Standards and can be divided into the following categories: Field equipment and instrumentation Controllers and controller panels Servers/workstations Network

18.6.7.1 Field Equipment and Instrumentation

The field equipment, instruments, and package systems will form the device level network of the control system. The specific equipment will be selected at a later stage, ensuring that the control and monitoring capabilities of the equipment meets the requirements of the control system design. Instruments provided as part of the Kitchener WWTP Stage 2 Expansion will follow the Region of Waterloo’s Design Standards Section 54004 (Instrument Standard). However, the selections will also take into account the existing instrumentation used in the associated areas of the existing plant(s), and related plant operations and maintenance experience. Typically, all analog input devices intended for continuous measurement of the corresponding process parameters required for monitoring and control purposes will be provided with associated transmitters and classified based on the wiring arrangement to the device. Analog input devices are usually wired using 2-wires, 3-wires and 4-wire wires; however, 2-wire field devices are the most common and preferred analog devices. The transmitter will be equipped with local display and mounted on the instrument itself or on a nearby wall or column, depending on the location.



Typically, all field discrete and analog signals will be connected through hard-wired connections. Wiring will be to the nearest PLC or remote I/O panel of the associated process PLC. The design of the PLC and SCADA I/O for a device, wherever possible, will fit into the standard groups of I/O defined, by the Region of Waterloo’s Design Standards Section 50001 (Standard Control Approach), for different types of devices, such as constant speed motors, variable speed motors, discrete valves, and modulating valves.

18.6.7.2 Controllers and Controller Panels

The design of the control system is based on the use of the Allen Bradley Logix family of controllers. The models will conform to the recommendations accepted by the Region as identified in the standard (Section 54003 – PLC Hardware and Section 54005 – PLC Panel Standard). PLCs will be segmented per process area for ease of control. Where possible, the PLC cabinets will be located in the electrical room or close proximity to the process area, mounted on a nearby wall or column.

18.6.7.2.1 Contract 1b – Biosolids Transfer Pumping

The Biosolids Transfer Pumping will be monitored/controlled via the new Digester Building ControlLogix PLC (KITRPU06). Location of the associated Instrument Control Panel (ICP) will be determined and detailed via the electrical engineering package during detailed engineering.

18.6.7.2.2 Contract 2b – Digestion

The Digestion process area, which consists of monitoring, controlling and/or communication with vendor control systems associated to two anaerobic digesters, their associated mixing pumps, sludge transfer pumps and the vendor supplied digester gas and boiler systems will be done via the new Digester Building ControlLogix PLC (KITRPU06). Location of the associated Instrument Control Panel (ICP) will be determined and detailed via the electrical engineering package during detailed engineering.

18.6.7.2.3 Contract 3a – Headworks Building

The Headworks process area, which consists of monitoring, controlling and/or communication with vendor control systems associated to two vortex grit separators, three grit pumps, two grit classifiers, two disposal bins, channel aeration, phosphorus removal system and the vendor supplied four raw wastewater fine screens, two wash compactors, process sump system and OCSs will be done via the new Headworks Building ControlLogix PLC (KITRPU01). Location of the associated Instrument Control Panel (ICP) will be determined and detailed via the electrical engineering package during detailed engineering.

18.6.7.2.4 Contract 4 – Plant 2 RAS/WAS Pumping

The Plant 2 RAS/WAS process area, which consists of monitoring and/or controlling six RAS pumps and two WAS pumps via the new Plant 2 RAS/WAS Pumping Station ControlLogix PLC (KITRPU02). Location of the associated Instrument Control Panel (ICP) will be determined and detailed via the electrical engineering package during detailed engineering.


The Plant 3 RAS/WAS process area, which consists of monitoring and/or controlling two aeration tanks, four secondary clarifiers, six RAS pumps and two WAS pumps, a scum collection chamber and a flow splitting chamber via the new Plant 3 RAS/WAS Pumping Station ControlLogix PLC (KITRPU03). Location of the associated Instrument Control Panel (ICP) will be determined and detailed via the electrical engineering package during detailed engineering.




The Plant 4 RAS/WAS process area, which consists of monitoring and/or controlling two aeration tanks, four secondary clarifiers, six RAS pumps and two WAS pumps and a scum collection chamber via the new Plant 4 RAS/WAS Pumping Station ControlLogix PLC (KITRPUXX - TBD). Location of the associated Instrument Control Panel (ICP) will be determined and detailed via the electrical engineering package during detailed engineering.

18.6.7.2.7 Contract 5b – WAS Thickening

The WAS Thickening process area, which consists of monitoring, controlling and/or communication with vendor control systems associated to two WAS holding tanks, three WAS pumps, two TWAS holding tank w/ associated mixing pumps, two TWAS transfer pumps, one thickened filtrate tank, two filtrate pumps and the vendor supplied rotary drum thickening (RDT), polymer and odour systems will be done via the new Thickening Building ControlLogix PLC (KITRPU05). Location of the associated Instrument Control Panel (ICP) will be determined and detailed via the electrical engineering package during detailed engineering.

18.6.7.2.8 SCADA Computers and Panel Mounted HMI Devices

The existing SCADA application, residing on the two (2) existing servers located in the Administration Building, will be updated. It should be noted that, for this PDR, the existing SCADA servers’ capacity is considered sufficient for the upgrades within the scope of the Project. The validity of this basis will be confirmed during the detailed design stage. Prior to the conclusion of this project, a new SCADA server system will be configured in the new administration building such that all functionality will be located in the new building, thereby allowing for the decommissioning of the existing servers. It is assumed that panel mounted operator interface terminals (OITs) will be located on each MCP within the different areas throughout the plant.

18.6.8 Network Architecture

The existing plant wide PLC/SCADA network will be extended to accommodate the new PLCs and the new Operator Workstations. Following the existing network architecture, the expansion network will also utilize a combination of fibre and copper media and will be interconnected with individual switches, redundant area switches, and core switches in order to enhance the reliability of the system and reduce the risk of failure. A new network access closet will be provided, in coordination with the Region, for the new Administration Building. This network access closet will be a duplicate of the existing system. The Preliminary Network Architecture Drawing (presented in Appendix A) illustrates the connection of all new devices to the nearest network access closet, maintaining the philosophy of the existing architecture. It should also be noted that, for this PDR, the capacity of the existing network access panels within the Administration Building is considered sufficient for the additional connections required within the scope of the project. The validity of this basis will be confirmed during the detailed design stage. The Region will supply and configure core switches, distribution switches and routers, as required. The Region’s IT services group will be consulted during the detailed design stage to provide assistance/procedures for procuring IT hardware through the Region’s current preferred list of IT hardware vendors.



18.6.9 SCADA System Software

The requirements for PLC and SCADA software development will be based on application of the standard software modules for different field devices, as well as for analog inputs and discrete alarm processing. The baseline application provided by the Region will be updated to include the specific process requirements. Automatic control will be organized in a logical manner and will include detailed descriptions and comments that are meaningful to the end user. Wherever new devices are wired to an existing Plant PLC, it will be coordinated with the Region such that the latest version of the existing program is obtained, and that no changes are made to the affected PLC until the updated program is commissioned. All SCADA development required for this Project will be eventually integrated with the existing Plant-wide SCADA application. A detailed implementation plan will be developed during the detailed design in coordination with the Region.

18.6.10 Constructability Considerations for Integration with Existing System

Where possible, process areas will be commissioned in parallel with the existing controls until which time they are adequately tested and ready for the online SAT. However, it is anticipated that, during some phases of construction, temporary shut downs of the existing control equipment will be necessary, requiring the process equipment to run in LOCAL mode. For example, in many cases the new code will be integrated within existing PLCs. As such, careful staging will be planned out, in coordination with the Region, to minimize the impact on day-to-day plant operations.

18.6.11 Network Architecture Drawing

The preliminary network architecture drawing is presented in Appendix A.

18.7 Energy Management Plan

18.7.1 Purpose

The objective of the Energy Management Plan is to outline the energy efficiency measures that the design team intends to incorporate into the design of the Kitchener WWTP Phase 3 upgrades. Overall, the energy management plan is intended to minimize project energy requirements by using the best practices in energy management technology specific to the project design. The approach will be implemented through detailed design.

18.7.2 Requirements

The Kitchener WWTP Phase 3 Upgrades project will incorporate an energy management and sustainable design approach in the following areas as a minimum: Design of building envelopes and systems to minimize heating, ventilation, and AC requirements Use of natural light wherever feasible to reduce the requirement for other lighting systems Use of energy efficient water heating systems The drive systems for mechanical equipment will be equipped with premium efficiency motors, VFDs and power

factor correction equipment, as appropriate Use of energy efficient lighting systems; switching facilities, timers and occupancy sensors to reduce lighting and

space heating requirements in areas not continuously occupied



Power consumption monitoring and logging in each MCC Power factor correction of no less than 0.90 The new Administration Building will be designed to a minimum LEED Silver standard

18.7.3 NFPA 820

The main objectives in the design of the Kitchener WWTP buildings are to meet the MOE requirements with respect to odour control and to ensure full compliance with the ventilation standards prescribed by the NFPA 820 Standard for Fire Protection in Wastewater Treatment and Collection Facilities, 2012 Edition. The design will fully exploit NFPA 820 provisions that allow selective measures to be implemented to reduce heating energy in cold climates. The measures described in the following sections (as per NFPA 820 Chapter 9) will be considered.

18.7.3.1 Classified areas

Dual ventilation rates for NPFA 70, Class I, Division 1 and Division 2 areas is permitted under provisions of this standard, provided that the following criteria are met: The low ventilation rate is not less than 50 percent of the rate specified in the NFPA Guidelines The low ventilation rate is in operation only if the supply temperature is 10º C (50ºF) or less The high ventilation rate is not less than that specified in the NFPA Guidelines

The high ventilation rate will be in effect whenever the supply air temperature is above 10ºC (50ºF), whenever the ventilated space is occupied, or whenever activated by approved combustible gas detectors set to function at 10 percent of the lower flammable limit (LFL).

18.7.3.2 Unclassified areas

Recirculation of up to 75 percent of the exhaust airflow for unclassified areas is permitted provided that the following criteria are met: The re-circulated air and outdoor air flow rate total is not less than 6 air ACH

Recirculation does not occur during occupancy. Buildings will be equipped with push buttons to comply with this requirement. The pushbuttons will allow personnel to manually override the lower ventilation rate prior entering the building.

18.7.4 Ontario Building Code (2006)

All new buildings that will be constructed as part of the Phase 3 Upgrades, with the exception of the new Administration Building, may be classified under the category of “industrial processing” per Article 12.2.1.2-5(b) of the 2006 version of the OBC and therefore exempt from following the energy efficiency requirements of part 12 and supplementary standards SB-10 of the building code. In addition, for purposes of the Code WWTPs may also be categorized as Pumping Stations with a Group F, Division 3 occupancy and are also exempt from following energy efficiency requirements of the code under this provision. However, in keeping with the Region expressed desire to minimize project energy requirements, we will meet or exceed OBC requirements for energy efficiency for all the Kitchener WWTP Buildings. The current version of the OBC (2006) provides designers with choices on how to address energy efficiency in non-residential buildings and larger-scale residential buildings by referencing the Model National Energy Code for Buildings (MNECB) as well as ASHRAE/IES 90.1-2010 “Energy Standard for Buildings Except Low-rise Residential



Buildings”. The code requires that buildings be designed to exceed the energy efficiency requirements of the MNECB by not less than 25% or ASHRAE 90.1 by not less than 5%. The ASRHAE 90.1 standard upon which the latest OBC is based provides minimum energy-efficient requirements for the design and construction of new building and their systems, and criteria for determining compliance with these requirements. The provisions of this standard apply to: 1. Envelope of buildings 2. Heating, ventilating, and air conditioning 3. Service water heating 4. Electric power distribution and metering provisions 5. Electric motors and belt drives 6. Lighting Table 131 presents a comparison between OBC 2006 energy efficiency requirements and the values that we intend to apply to the design of Kitchener WWTP Buildings. As can be seen, it is currently the intent that the design will generally exceed OBC 2006 requirements. Table 131 Comparison of 2006 OBC Requirements and Proposed Building P Values

Building Element Sub-Element OBC 2006 Kitchener WWTP Buildings

Envelope

Roof R=30 R=32

Wall R=15.2 R=18 (average)

Walls below grade R=10 R=10

Door R=2.5 R=15

Window R=2.85 R=2.85 (average)

Electrical Motors (1800 rpm)

10 Hp Electric motor 89.5% Eff+ 89.5% Eff

100 Hp Electric Motor 94.1% Eff+ 95.4% Eff

200 Hp Electric Motor 95% Eff+ 96.2% Eff

Lighting

Ballast Efficacy Factor 1.2* 11 W/m2

Process Area Lighting Power Densities+ N/A 2 W/m2

Office Area Lighting Power Densities 11 W/m2 3 W/m2

Outdoor Lighting 2.2 2 W/m2 Notes: * 2 - F32 T8 Lamps (347 V);

+ This is the efficiency achieved at the optimum performance point under ideal conditions and may not be attained at the normally operating duty point(s);

18.7.5 Building Envelope

The building envelope elements will be configured to provide high insulation levels that minimize building heating, ventilation, and air conditioning requirements, as outlined in Table 131. Green roof systems will be further investigated during the design to provide better roof insulation and storm water benefits, as applicable.

18.7.6 HVAC

18.7.6.1 General

The main objective is to design sustainable HVAC systems in order to minimize the project energy requirements by using the best available energy management technology, including free cooling and free heating, as much as possible.



Proposed energy-conserving enhancements for process and non-process area HVAC systems have been based on economic feasibility and considerations related to NFPA, durability, occupancy and odour control requirements. As discussed in Section 1.3 NFPA 820, a major focus of the HVAC design will be the reduction of ventilation quantities whenever through the reduction of ventilation rates to process areas during unoccupied periods Occupied/unoccupied temperature control will be applied to process areas. When the area is occupied heating will be set at a high temperature (e.g. 18 ºC), but when unoccupied heating will be set at a lower temperature (e.g. 10ºC) in order to conserve energy. Operators will have the ability to override the set point from a local push button and also through the building automation system (BAS). Consideration will be given to turning off or reducing air flow rates in all process and non process areas not affected by NFPA or odour issues. Control will be through local timers or the BAS system. A heat recovery system will be considered to reclaim the heat from the Headworks and Thickening buildings and to use it to pre-heat ventilation air supplied to the buildings. The heat recovery system will be a “heat-pipe” type. The system will extract heat from the Headworks and Thickening buildings exhaust air to preheat the outdoor air introduced to the buildings make-up air unit. This system will operate when the outdoor temperature is below an optimal value to optimize energy recovery vs. energy consumption. Ultra high efficiency and high efficiency motors will be provided for AHUs, where applicable.

18.7.6.2 Kitchener WWTP buildings

There will be four recirculating AHUs, three serving the RAS/WAS pumping stations (AHU-2, 3, 4) and the other serving part of the digester building (AHU-1). There will be three make up air units with corresponding exhaust fans serving the Headworks Building (AHU-1, 2) and Thickening facility (AHU-1) .In energy centre there will be two exhaust fans (FN-5 ,FN-6) which provide ventilation for the generators and one small exhaust fan(FN-7) provide ventilation for the gen-sets room. One supply and one exhaust fan (FN-1, FN-2) will provide ventilation for existing biosolids transfer pump room; this pump room is a part of the existing administration building. AHUs for the RAS/WAS pumping stations and for Thickening facility will be gas fired units and heating coil for Headworks Building units will be hydronic type. The 100% outdoor air make up air units in Headworks and Thickening buildings will consist of two supply and two return/exhaust fans units with variable speed motors to provide flexibility in the air flow rates supplied to the spaces served as well as a degree of redundancy. Hydronic heating coils mounted in the Headworks Building’s units will be controlled to temper the supply air to the spaces to maintain them at a base temperature of 10°C during unoccupied periods and 18oC during occupied periods. Occupancy will be selected from pushbutton stations located at the entrances to the process areas affected or a request made remotely from SCADA. The 100% outdoor make up air units in Headworks and Thickening buildings will have a pre-heat coil as part of a heat-pipe air-to air heat recovery system, in addition to a heating coil. The heat reclaim coil will be mounted in the exhaust air stream from the Headworks and Thickening buildings AHUs to utilize the heat given off from the equipment and exhaust air. The pre-heat and heating coils will be controlled to temper the supply air to the spaces to maintain them at a base temperature of 10oC during unoccupied periods and 18oC during occupied periods. Occupancy will be selected from pushbutton stations located at the entrances to the process areas affected or a request made remotely from SCADA. The AHUs will be outfitted with VFD’s to allow adjustments to fan speeds during setup but will normally be operated as a constant speed unit.



The recirculating air in RAS/WAS pumping station and digester building AHUs will have mixing dampers (outside air, return air and exhaust air) and will be set up to provide 25 to 30% outdoor air for ventilation purposes. The units will be outfitted with VFDs to allow adjustments to fan speed during setup but will normally be operated at a constant speed. The unit heating coils will be controlled to temper the supply air to the spaces to maintain them at a base temperature of 10°C during unoccupied periods and 18°C during occupied periods. The volume of air to the spaces will also be varied so that air recirculation of up to 75% will be provided during non-occupancy and this will be increased to 100% outdoor air during occupancy or whenever required for free cooling purposes. Occupancy mode will be initiated from either pushbutton stations located at the entrance to the spaces or a request made remotely via SCADA. If the space is not returned to unoccupied mode within a reasonable timeframe (e.g. 8 hours), an alarm will be generated to ensure that it does not remain in an energy intensive mode of operation for extended periods of time.

18.7.6.3 Hydronic Heating System

There will be three new hot water natural/digester gas boilers (fire tubes) for digester building which is providing heating for the heat exchangers and building area. These boilers will be equipped with low emission option when firing natural gas. Two new high efficiency gas fired hot water boilers (cast iron type) with pumps, and glycol components will provide heating for Headworks Building and AHUs. Variable speed pumps are used to circulate heated glycol to the various heating and ventilation systems in the building. As the demand for heat decreases the flow is reduced.

18.7.6.4 Energy Savings Attributable to Energy Reduction Measures (ERMs) Applied to Ventilation

The impact of the various measures being contemplated is indicated in Table 132 and Table 133. The energy analysis is based on the energy consumption numbers resulting from the Primary HVAC Cost Analysis carried out as part of the mechanical preliminary design. Table 132 and Table 133 compare the energy consumption attributable to a given energy reduction measure to a baseline energy consumption. The baseline energy consumption is that which would result if none of the energy reduction measures described in Section 1.6. 1 were carried out. For comparison purpose both the heating and electrical energy numbers are expressed in kWh. Table 132 Energy Impact of Energy Reduction Measures Applied to Headworks and Thickening

Buildings Ventilation Air Energy

Reduction Measure No.

Energy Reduction Measure

Heating Energy (kWh)

Electrical Energy (kWh)

Heating Energy Reduction

Electrical Energy Reduction

- Baseline Energy 7,256,204 5,804,961 N/A N/A

1 Heat Recovery 7,256,204 5,804,961 3,192,730 (44%) 0

Table 133 Energy Impact of Energy Reduction Measures Applied to RAS/WAS and Digester Buildings

Ventilation Air Energy

Reduction Measure No.

Energy Reduction Measure

Heating Energy (kWh)

Electrical Energy (kWh)

Heating Energy Reduction

Electrical Energy Reduction

- Baseline Energy 3,188,000 2,656,250 N/A N/A

2 Reduce Flow During Unoccupied

Periods 1,594,000 1,328,125 1,594,000 (50%) 1,328,125 (50%)

3 Reduce Temperature During

Unoccupied Periods 1,912,800 2,656,250 1,275200 (40 %) 0



Energy Reduction Measure No. 1 involves recovering waste heat from the exhaust air in Headworks and Thickening Buildings to preheat the air supplied air Energy Reduction Measure No. 2 involves reducing air flow rates for those units that normally provide 6 to 3 ACH and reducing the outside air from 100% to 25% in units that provide a constant air flow rate at all times (i.e., recirculation units). This measure has a significant impact on both heating and electrical energy, particularly the latter because of the exponential relationship between fan power and fan speed. Energy Reduction Measure No. 3 involves reducing the temperature in all process areas from 18°C to 10°C during unoccupied periods.

18.7.7 Controls

The HVAC systems for new facilities will be controlled by a networked BAS to allow sharing of common point data (e.g., outdoor temperature). This BAS system will integrate multiple building functions including equipment supervision and control, alarm management, energy management, information management, and historical data collection and archiving. The BAS will consist of the following: Network Controllers, Field Controllers Equipment Controllers, Terminal Controllers, Local Display Devices, and a Personal Computer based Operator Workstation. Local control panels will include an operator interface for locally changing HVAC control set points and monitoring HVAC control status. A new BAS system will be provided to ensure accurate control and monitoring of all HVAC equipment as well as the ability to maintain the various energy saving strategies outlined above.

18.7.8 General Electrical

18.7.8.1 Distribution Voltage

The electrical design will be geared towards minimizing the electrical distribution system losses by using the highest voltage practical to suit the application. MCCs will be located close to the point of use to avoid long runs of cables. In order to provide site wide power distribution and minimize cable sizing and voltage drop a voltage of 13.8 kV was selected to match the incoming utility voltage. The 13.8 kV site distribution will be distributed to field located outdoor pad mounted transformers adjacent the respective Plant buildings and/or process loads.

18.7.8.2 Voltage Levels

The voltages presented in Table 134 are proposed to be used for various types of electrical equipment.



Table 134 Recommended Voltage Levels For various Types Of Electrical Equipment Item Type/Rating Voltage Phase

Lighting Fluorescent, LED, high pressure sodium, metal halide and incandescent 120 single

Heating Small Up to 2500 W 120/208 single

Large, and over 600 three

Motors 0.5 kW and less 120 single

Greater than 0.5 kW 600 three

Motor Controls All 120 single

Outlets Convenience 120 single

Special Outlets As required Single or three

18.7.8.3 Power Factor Correction Capacitors

Power factor correction capacitors will be used for constant speed motors 20 HP and greater. Capacitors will either be applied to the motor load directly or thru switching banks at each MCC. The target correction will be no less than a power factor of 0.90. Power factor capacitors shall be used as required.

18.7.8.4 Transformers

Transformers to supply 120/208V shall be dry type and suitable for the area in which they are to be located. Transformers will meet the requirements of and use the energy efficiency evaluation methodologies given in NEMA TP 1-2002 “Guide For Determining Energy Efficiency For Distribution Transformer.”

18.7.8.5 Lighting Systems

Lighting systems will be based on providing the best overall life cycle cost to suit the application. In general, lighting shall be as follows: Plant Process Areas: T5-Fluorescent Outdoor Lighting: LED New Administration Building: LED All areas will be controlled by lighting control devices such as timers, photocells, occupancy sensors, motion sensors and/or photocells. Consideration will also be given to provide area lighting and specific task lighting where applicable

18.7.8.6 Energy Efficient Motors

High efficiency motors will be specified depending on the application. Constant speed motors larger than 25 HP will be controlled through soft starters or VFDs, as appropriate.

18.7.8.7 VFDs

VFDs will be used where cost effective or to suit process. All VFD applications shall meet the IEEE 519 Guideline “Recommended Practices and Requirements for Harmonic Control in Electrical Power Systems”. VFDs will use harmonic reduction technology.



18.7.8.8 Power Monitoring

The main switchgear and field located MCCs will be provided with digital metering integrated into the Plant SCADA system. The power monitoring system shall record and trend real time power consumption as well as trend power quality. The power monitoring will be utilized by the plant SCADA system to manage plant Peak demand by avoiding the overlapping of plant process loads where feasible as well as management of plant emergency loads. The individual meter shall be configured to monitor the following: Voltage, amperage, power factor, KVAR, frequency, and harmonic distortion 15 minute kW load Monthly kWh consumption, average kW, and peak kW Power quality monitoring Alarm logs Reconciliation with monthly Utility billing and energy usage

18.7.8.9 Co-Generation

The main 13.8 kV switchgear has been designed to accommodate future inclusion of a cogeneration machine producing electricity from the utilization of digester gas. The intent of the cogeneration is to displace plant load for purposes of peak shaving while paralleled to the utility source. The heat recovery associated with the cogeneration will be used to displace plant thermal loads.

18.7.9 LEED Standard and Sustainable Design

As per the Region’s policy, all new regional building with larger than 500 m2 of occupied space are to be designed to LEED Silver standard. This policy only applies to the new administration building at the Kitchener WWTP and excludes the process buildings due to their occupancy. However, in keeping with the Region’s vision to promote energy efficiency, sustainable design principles derived from LEED standards will be used for the process buildings. The use of sustainable design principles derived from LEED standards will result in buildings that are respectful of their surroundings while being durable, flexible and energy efficient. Sustainable design principles and LEED certification will form an integral part of the overall Energy Management Plan for the facility. An overview of some of the design principles related to energy management proposed for the facility are described below.

18.7.9.1 Reducing Heat Island Effects

Heat island is a phenomenon whereby the area in and around a building is a few degrees warmer than its surrounding. This condition is caused by the use of materials with a low solar reflective index such as dark hardscapes (e.g., asphalt). These surfaces absorb heat and then radiate it out to their surroundings. Heat islands also occur on the roofs of buildings. The overall effect results in an increase in cooling demand on the building HVAC systems and an increase in energy consumption. Heat islands are also known to impact health. By reducing heat islands we can reduce energy consumption and promote a healthier environment. Strategies to reduce heat islands include: 1. Vegetative or Green roofs 2. Using roofing membranes with a high reflective index (high albedo) 3. Provide shade to hardscape surfaces by using shading devices and trees 4. Open grid-pavement systems We propose using a combination of the above strategies to reduce the overall heat island effect for the overall plant.



18.7.9.2 Light Pollution

Light pollution is excessive and unnecessary artificial light. Apart from wastage of energy, light pollution has the additional negative effects of reducing visibility of the night sky, disrupting nocturnal ecosystems and causing adverse health effects on humans. Some of the ways by which light pollution can be reduced include: 1. Automatic reduction of output of non-emergency interior lights in a building that have a direct line of sight to

exterior openings at times when the building is not occupied 2. Automatic shields at all exterior opening in the direct line of site of non-emergency interior lights 3. Partially or fully shield exterior lights 4. Light exterior areas only as required for safety and comfort

Reducing the amount of light pollution will have a positive impact on the site’s surroundings and lead to energy efficiencies. These measures would be undertaken for the new administration building but can be extended to the overall plant and process buildings where functionally possible.

18.7.9.3 Optimizing Energy Performance

As discussed in Section 1.1.4, the OBC (2006) requires that buildings demonstrate a 25% cost improvement compared with the baseline building performance as outlined in the Model National Energy Code for Buildings (MNECB). For a building to be considered for LEED certification, the minimum threshold is 23% which is lower than the OBC. We intend to exceed the LEED and OBC requirements and target a cost improvement of 35% for the new administration building and meet the code requirements for the other process buildings. As noted in 1.1.4 the process buildings are exempt from energy efficiency requirements of the code due to their occupancy (i.e., F-3); however, in keeping with the Region’s vision for energy efficiency, we intend to target their improvement which we believe will result significant cost benefits over the long term. In order to achieve cost improvements, particular attention has to be paid to the design: 1. Exterior envelope of buildings 2. Heating, ventilating, and air conditioning 3. Service water heating 4. Electric power distribution and metering provisions 5. Electric motors and belt drives The specific measures to be undertaken have been discussed in depth in the sections above.

18.7.9.4 Daylighting

Daylighting refers to a design strategy by which natural light, either direct sun or diffused light from the sky, is carefully admitted into a building in a controlled manner in order to reduce the dependence on artificial lighting thereby optimizing energy performance and reducing energy costs. Effective daylighting design can result in a productive and stimulating work environment, due to the many known health benefits that it affords. Factoring in daylight availability, controlling glare and balancing heat loss/gain are some of the design considerations in effective daylighting. LEED places emphasis on daylighting and sets thresholds for achieving points in their certification system. We will provide daylighting to 75% of the regularly occupied spaces within the new administration building and have are included the provision of daylighting in the process buildings where it does not interfere with function. The following design strategies are proposed for the new administration building: 1. Building orientation to maximize the use of natural light 2. The use of light shelves to allow penetration of light deep into the building floor plate



3. Overhangs and solar shading devices to reduce glare 4. High performance glazing systems 5. Skylights and Clerestory windows 6. Daylight responsive lighting controls

18.7.9.5 On-Site Renewable Energy

The use of On-Site renewable energy sources is another way to off-set building energy costs. The LEED rating system provides incentives for providing a percentage of the buildings total energy from renewable sources. These measures will be used for the new administration building. We will make use of photovoltaic panels to offset some of the energy usage for the building’s hot water heating needs and a geo-thermal system to feed heat pumps for the HVAC system.

18.7.9.6 Other Sustainable Design Features

As part of LEED certification for the new administration building we will use a number of sustainable design features and principles that go beyond energy management and efficiency. These design features will result in conservation of resources, restoration of habitat, reduction of overall greenhouse gas emissions and a creation of a healthier environment for building occupants while limiting the impact of the development on its surroundings. These features are: 1. Protect and restore the natural habitat during construction by limiting the construction foot print 2. Attain water efficiency and target water use reduction by making use of water-efficient landscaping, using rain-

water and recycled grey water for non-potable use and using low flow washroom fixtures 3. Do not use CFC for refrigeration and target to not use refrigerants at all is possible to minimize depletion of the

ozone layer 4. Reduce and divert construction waste by as much as 75% 5. Target that at least 10% of the material used in construction has recycled content 6. Target that at least 10% of the material used in construction is locally harvested, extracted and/or manufactured

locally to reduce reliance on transportation and thereby reducing greenhouse gas emissions 7. Improve indoor air quality for occupants by monitoring CO2 concentrations, increase the effectiveness of the

ventilation systems, make use of materials with a low VOC content, provide pollutant control systems at entryways and provide exhaust of pollutants and hazardous systems where they arise

8. Implement an indoor air quality control program during construction and flush out building mechanical systems prior to occupancy

9. Provide individual lighting and thermal controls to individuals to improve indoor environmental quality for the occupants

10. We also recommend making use of green housing keeping practices and installing an education kiosk at the reception to educate users and visitors about the features and use of the facility



19. Construction 19.1 Construction Sequencing

A project of the scope and cost of the Kitchener WWTP Phase 3 Upgrades could only be completed as a single contract by a very limited number of General Contractors in the Province of Ontario. In order to achieve maximum competition during bidding, it is desirable to limit contract values to less than approximately $75 million. There are a relatively large number of General Contractors who can undertake projects of this size. Significantly fewer can undertake projects of $100 million or greater. The use of multiple contracts will allow the Region to better control the overall project staging and areas impacted by construction at any given time. Also, multiple construction contracts enables improved control of the Region’s cash flow. The 5 main contracts proposed are: Contract 1

o Contract 1a – Lagoon decommissioning o Contract 1b – Digested sludge transfer pumping

Contract 2 o Contract 2a – Energy centre o Contract 2b – Anaerobic digestion

Contract 3 o Contract 3a – Headworks o Contract 3b – Tertiary treatment and outfall

Contract 4 – Plant 3 and 4 Secondary Treatment, Blower Building, and Plant 2 RAS/WAS pumping station Contract 5

o Contract 5a – New Administration Building o Contract 5b – WAS thickening

Miscellaneous Upgrades – Plant 1 decommissioning, sludge thickening and miscellaneous works These proposed contract packages were selected based on the timing requirements, type of work, spatial separation requirements and contract value. The contracts and proposed staging have also taken into consideration the other works currently underway at the Kitchener WWTP, including the Plant 2 Upgrades and the UV disinfection and effluent pumping. Table 135 summarizes the proposed contract sequencing plan.

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omm

itmen

t to

have

com

plet

e by

201

5 S

peci

alis

t civ

il C

ontra

ctor

requ

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not

con

sist

ent w

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echa

nica

l con

tract

or

for W

WTP

wor

ks

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agem

ent o

f mat

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n ou

tcom

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ract

eriz

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ks s

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sch

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d m

onth

s to

ext

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ossi

ble

to m

inim

ize

odou

r im

pact

s

1b -

Dig

este

d Sl

udge

Tr

ansf

er P

umpi

ng

Dem

oliti

on o

f exi

stin

g tra

nsfe

r pum

ps a

nd p

ipin

g I

nsta

llatio

n of

new

pum

ps, p

ipes

and

acc

esso

ries

Yar

d pi

ping

and

con

nect

ion

to e

xist

ing

forc

emai

n to

W

WR

MC

Mus

t be

com

plet

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efor

e ex

istin

g bo

oste

r sta

tion

at la

goon

s is

de

com

mis

sion

ed

Mus

t be

com

plet

ed b

efor

e C

ontra

ct 2

to a

void

con

flict

s in

wor

k sp

aces

2a -

Ener

gy C

entre

New

pow

er s

uppl

y an

d hi

gh v

olta

ge t

rans

form

ers

New

hig

h vo

ltage

sta

ndby

pow

er g

ener

ator

s N

ew p

ower

sup

ply

to D

iges

ters

(Con

tract

2b)

Pow

er c

entre

requ

ired

to p

erm

it co

nstru

ctio

n/op

erat

ion

of o

ther

new

pro

cess

ar

eas

(exi

stin

g sy

stem

can

not s

ervi

ce n

ew w

orks

) D

ecom

mis

sion

ing,

dem

oliti

on a

nd re

mov

al o

f aba

ndon

ed p

roce

ss ta

nks

(dig

este

rs a

nd p

rimar

y cl

arifi

ers

sout

h of

the

exis

ting

dige

ster

s)

Coo

rdin

atio

n w

ith K

itche

ner W

ilmot

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er

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er d

istri

butio

n to

be

coor

dina

ted

with

oth

er c

ontra

cts

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itcho

ver o

f pow

er c

onne

ctio

n fro

m e

xist

ing

conf

igur

atio

n (1

3.8k

V Pr

imar

y O

utdo

or S

witc

hgea

r to

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ting

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door

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stat

ion)

to n

ew c

onfig

urat

ion

(13.

8kV

Prim

ary

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door

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itchg

ear t

o N

ew E

nerg

y C

ente

r to

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ting

Out

door

Sw

itchg

ear)

Tem

pora

ry p

ower

and

/or p

artia

l Pla

nt s

hutd

own

may

be

requ

ired.

2b -

Anae

robi

c D

iges

tion

New

dig

este

r con

trol b

uild

ing

Upg

rade

Sec

onda

ry D

iges

ter N

o. 3

for s

ludg

e an

d di

gest

er g

as s

tora

ge

Upg

rade

s to

exi

stin

g pr

imar

y di

gest

ers

U

pgra

des

to d

iges

ter a

nd n

atur

al g

as h

andl

ing

syst

ems

Con

stru

ctio

n of

new

dig

estio

n co

mpl

ex

Dem

oliti

on o

f exi

stin

g bo

iler s

yste

m

Dig

este

r upg

rade

s re

quire

d to

add

ress

cod

e de

ficie

ncie

s, o

pera

tiona

l re

quire

men

ts

Mai

ntai

ning

ope

ratio

ns in

exi

stin

g di

gest

ers/

adm

inis

tratio

n bu

ildin

g M

aint

ain

heat

ing

of b

uild

ings

ser

vice

d by

exi

stin

g bo

ilers

unt

il ne

w b

oile

rs in

se

rvic

e W

aste

gas

bur

ners

to b

e bu

ilt fi

rst

Tem

pora

ry s

ludg

e tra

nsfe

r cha

mbe

r nee

ded

for n

ew b

uild

ing

cons

truct

ion

and

man

hole

relo

catio

n W

hen

prim

ary

dige

ster

No.

6 a

nd s

econ

dary

dig

este

r No.

3 a

re ta

ken

offli

ne,

raw

slu

dge

will

be d

iver

ted

to p

rimar

y di

gest

er N

o. 5

thro

ugh

its o

verfl

ow b

ox

3 - H

eadw

orks

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scr

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plet

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andl

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em

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vor

tex

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rem

oval

sys

tem

com

plet

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ith g

rit

hand

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syst

em

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ur c

ontro

l fac

ility

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mic

al a

dditi

on s

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m fo

r pho

spho

rus

rem

oval

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dwor

ks re

quire

d to

repl

ace

exis

ting,

w

hich

is b

eyon

d us

eful

life

exp

ecta

ncy

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dwor

ks m

ust b

e co

mpl

eted

prio

r to

Plan

ts 3

and

4 c

onst

ruct

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to a

void

co

nflic

ts

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dwor

ks s

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rior t

o co

mm

issi

onin

g ne

w s

econ

dary

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atm

ent a

nd d

iges

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o m

inim

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solid

s ca

rry-o

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nto

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esse

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AEC

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ity o

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DR

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Fina

l Rep

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RP

T-20

12-0

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R- 6

0159

482.

Docx

21

9

Con

trac

t K

ey C

ompo

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onst

rain

ts

Deg

ritte

d se

wag

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mpi

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tatio

n D

emol

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of e

xist

ing

Hea

dwor

ks B

uild

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Con

stru

ctio

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pilo

t stu

dy fa

cilit

y

Lag

oon

deco

mm

issi

onin

g m

ust b

e co

mpl

ete.

Lag

oon

mus

t be

parti

ally

fille

d to

ac

com

mod

ate

cons

truct

ion

of h

eadw

orks

U

pgra

de to

exi

stin

g ac

cess

road

and

new

alte

rnat

e on

-site

acc

ess

road

re

quire

d to

pro

vide

relia

ble

acce

ss fo

r con

stru

ctio

n an

d op

erat

ions

veh

icle

s M

aint

ain

acce

ss fo

r che

mic

al d

eliv

erie

s, a

nd o

pera

tions

. M

aint

ain

acce

ss to

exi

stin

g he

adw

orks

faci

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head

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d ra

w w

aste

wat

er d

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sion

s re

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d to

dire

ct fl

ow to

new

H

eadw

orks

3a -

Terti

ary

Trea

tmen

t and

Out

fall

New

terti

ary

treat

men

t fac

ility

cons

istin

g of

dis

k fil

ters

N

ew o

utfa

ll to

Gra

nd R

iver

I

nflu

ent c

hann

els/

sew

ers

from

Pla

nt 2

and

Pla

nt 3

/4

Con

nect

ion

from

UV

Dis

infe

ctio

n an

d Ef

fluen

t Pu

mpi

ng

Dem

oliti

on o

f exi

stin

g ou

tfall

and

diffu

ser s

truct

ure

in ri

ver

Out

fall

cons

truct

ion

tech

niqu

es a

nd ti

min

g w

ill b

e re

stric

ted

to s

atis

fy D

FO,

GR

CA

requ

irem

ents

R

equi

res

UV

Dis

infe

ctio

n an

d Ef

fluen

t Pum

ping

to b

e co

mpl

ete

Flo

od p

rote

ctio

n re

quire

d F

low

div

ersi

ons

and

bulk

head

s re

quire

d.

Ter

tiary

trea

tmen

t com

mis

sion

ing

timin

g to

be

just

prio

r to

Plan

ts 3

and

4 to

m

eet e

fflue

nt o

bjec

tives

4 - P

lant

3 a

nd 4

Se

cond

ary

Trea

tmen

t, Pl

ant 2

Upg

rade

s,

RAS

/WAS

Pum

ping

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Pla

nt 3

and

4 s

econ

dary

trea

tmen

t wor

ks

incl

udin

g ae

ratio

n ta

nks,

sec

onda

ry c

larif

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, R

AS/W

AS P

umpi

ng

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talla

tion

of n

ew b

low

ers

and

pipi

ng f

rom

Pla

nt 2

Bl

ower

Bui

ldin

g N

ew P

lant

2 R

AS/W

AS p

umpi

ng s

tatio

n D

emol

ition

of P

lant

1 a

nd re

loca

tion

of b

low

ers

to

Blow

er B

uild

ing

Req

uire

new

hea

dwor

ks fa

cilit

y to

be

oper

atio

nal t

o co

mm

issi

on P

lant

3 a

nd 4

R

equi

re P

lant

2 B

low

er B

uild

ing

to b

e co

mpl

ete

Req

uire

Pla

nt 3

and

4 o

pera

tiona

l prio

r to

deco

mm

issi

onin

g of

Pla

nt 1

R

equi

re P

lant

3 a

nd 4

to b

e op

erat

iona

l bef

ore

Plan

t 2 R

AS/W

AS p

umpi

ng

stat

ion

to e

nsur

e tre

atm

ent c

apac

ity a

vaila

ble

Exi

stin

g Pl

ant 2

RAS

/WAS

pum

ping

sta

tion

mus

t be

dem

olis

hed

prio

r to

cons

truct

ion

of th

e re

plac

emen

t pum

ping

sta

tion

5a -

Adm

inis

tratio

n Bu

ildin

g

Con

stru

ct n

ew A

dmin

istra

tion

Build

ing

Mod

ifica

tions

to e

xist

ing

Adm

inis

tratio

n Bu

ildin

g

Pla

nt 3

and

4 c

onst

ruct

ion

near

com

plet

ion

prio

r to

star

ting

Adm

inis

tratio

n Bu

ildin

g to

min

imiz

e im

pact

s on

sta

ff du

e to

con

stru

ctio

n

Wor

ks n

ot re

quire

d to

mee

t effl

uent

com

mitm

ents

. C

an b

e im

plem

ente

d af

ter n

ew fa

cilit

ies

com

mis

sion

ed

5b -

Slud

ge

Thic

keni

ng

Slu

dge

thic

keni

ng fa

cilit

y F

inal

SC

ADA

syst

em c

omm

issi

onin

g S

ite s

ecur

ity

Odo

ur c

ontro

l fac

ility

Wor

ks n

ot re

quire

d to

mee

t effl

uent

com

mitm

ents

. C

an b

e im

plem

ente

d af

ter n

ew fa

cilit

ies

com

mis

sion

ed

Coo

rdin

ate

with

adj

acen

t Ene

rgy

Cen

ter

Mis

cella

neou

s W

orks

D

emol

ish

stru

ctur

es in

Pla

nt 1

M

isce

llane

ous

plan

t upg

rade

s in

clud

ing

prim

ary

clar

ifier

s, s

econ

dary

cla

rifie

rs,

Req

uire

Pla

nt 3

and

4 o

pera

tiona

l prio

r to

deco

mm

issi

onin

g of

Pla

nt 1



19.2 Construction Staging and Schedule

The construction staging is divided into 8 distinct stages. Each stage identifies concurrent contract work, potential contractor parking and laydown areas, temporary roads, and parking areas for Region staff and operations. The Contracting staging drawings demonstrate that each contract area can be clearly delineated with respect to space and time allowing the project to proceed in such a fashion that the respective Contractor for each contract would take on the role of the Constructor. The following presents key features and issues identified at each stage with respect to Construction areas, delineation of Contracts and access to the plant during Construction. The construction staging and construction schedule are developed with the following constraints and deadlines: Region cash flow projections, contract value and spatial separation Contract 1a (Lagoon Decommissioning) is required to be completed prior to the end of 2015 Contract 3b (Tertiary Treatment) is required to be commissioned prior to Contract 4 (Secondary Treatment) Contract 4 (Secondary Treatment) Plant 3 and 4 are required to be commissioned by the end of 2017 The critical path of commissioning Plant 3 and 4 is affected by the completion of the following contracts:

o Contract 1a (Lagoon Decommissioning) and Contract 1b (Digested Sludge Pumping) must be completed prior to the start of Contract 3a (Headworks), in order to meet space constraints

o Contract 2a (Energy Center) must be completed prior to commissioning of Contract 2b (Digestion), and Contract 3a (Headworks) as both contracts will be powered by the Energy Center (Contract 2a)

o Contract 3a (Headworks) must be completed prior to the start of Contract 4 (Secondary Treatment), in order to meet space constraints

Figures contained in Appendix P present the construction staging drawings and focuses on the proposed construction contract areas, potential laydown areas and traffic management concept annually through the duration of the construction. A preliminary construction contract schedule provided in Appendix P shows the various stages, proposed contracts and dependencies. It should be noted that the proposed schedule incorporates a three (3) month float between Contract 3a and Contract 4 to avoid potential conflicts/delays if Contract 3a is not completed on time. Contract 4 also includes an inherent estimated 3 month float, which is not apparent on the schedule. This section provides a high level overview and analysis of the various issues, constraints and major features to consider at each construction stage. To facilitate complete understanding, this narrative is to be read in conjunction with the construction staging drawings and preliminary construction schedule in Appendix P.

19.2.1 Construction Stage 1 (from 12/2012 to10/2013)

In Construction Stage 1, Contract 1 is under construction. Contract 1a and Contract 1b are on opposite ends of the site, and do not spatially overlap, which allows flexibility to separate the two Contracts if desired. The advantage of separating the contracts would be to fast track tender and construction of Contract 1b, which would be desirable, as the new digested sludge pumps in Contract 1b must be commissioned prior to removing the existing sludge pumps, which are to be removed in Contract 1a. Access roads east of the digesters would be closed off due to the new piping installed under Contract 1b. Access for digester operations can be maintained by using the existing road north of the existing secondary digester. At the end of Stage 1, Contract 1a and Contract 1b would be constructed, and Contractors would be off-site. It is anticipated that some post project completion would required beyond this stage. Post project completion would be relatively minor, and should not interfere with contracts in Stage 2 with respect contractors occupying the same area in terms of space and time.



Contract 1 is on the fast track for design and completion to mitigate odours caused by the Lagoons, and is also required to be finished before Contract 3 can start.

19.2.2 Construction Stage 2 (from 10/2013 to 4/2015)

In Construction Stage 2, Contract 2 and Contract 3a are under construction concurrently. These two contracts are on opposite ends of the site, and do not spatially overlap. As these contracts will include major construction, various improvements to site access and parking areas will be required in order to manage traffic and access for the Contractor, Region and operations staff. The following improvements should be made at the beginning of Contract 3a construction: Installation of Security Gate at the front entrance of the plant Rehabilitation of the main plant entrance road Installation of a temporary road to bypass the Contract 3 construction site; the main road would be utilized by

Contract 3a contractors, and the temporary road would be utilized by the Contract 2 contractor, Region and operations staff.

Partial filling Lagoon 2 and creation of a parking and laydown area that will be utilized for these two contracts and all future contracts

Construction of a new interim parking area for Region staff and operations, west of the existing Plant 1 secondary clarifiers

It is anticipated that the cost these various improvements will be in the $2 to 3 million range. The construction of the new influent sewer under Contract 3a will block access into the plant. It is anticipated that this plant entrance can be maintained for the majority of the construction, and will only be blocked off during the new influent sewer construction period and when the existing Headworks Building and associated influent sewer are demolished. Key considerations for Construction Stage 2 include: Contract 2a is on the critical path, and must be completed prior to commissioning the new Headworks Building in

Contract 3a, and the new digestion complex in Contract 2b because both contracts will be powered by the Energy center.

Various internal road shutdowns will need to be coordinated to install underground ductbanks for the electrical distribution under Contract 2a.

Coordination of Contract 2a and Contract 3a Contractors will be required in order to bring power to the new Headworks Building.

At the end of Stage 3, Contract 2a and Contract 3a would be constructed. Contract 3a must be constructed prior to starting Contract 4 to maintain separation by time between contracts.


In Construction Stage 3, Contract 2b continues to be under construction. This stage represents float in the construction schedule, which provides flexibility if Contract 3a cannot be completed on time, or flexibility to fast track the tender and construction of Contract 4, if Contract 3a is completed on time or earlier. It should be noted that the demolition of the existing headworks would be the last major construction activity in Contract 3a. As this work provides adequate spatial separation with Contract 4, this work could occur in this float period, and into the early periods of Construction Stage 4.




In Construction Stage 4, Contract 2b continues to be under construction, and Contract 4 is under construction.

Contract 4 construction can be separated into two distinct phases based on certain process constraints: 1. Construction of Plant 3 and 4: This construction is required by the Region to be completed by the end of 2017.

The constraint on the completion of this construction is that the Tertiary Treatment building and new outfall under Contract 3b are must be constructed prior to commissioning Plant 3 and 4.

2. Construction of Plant 2 RAS/WAS pump station: The construction of the Plant 2 RAS/WAS pump station requires a shutdown of Plant 2. In order for Plant 2 to be shutdown, Plant 3 and 4 must be commissioned.

Based on previous AECOM projects of similar or larger scope, it is anticipated that Plant 3 and 4 construction could be completed earlier than shown on the schedule. The current schedule shows a worst case scenario of 635 days. A best case scenario is likely to be in the range of between 500 and 540 days. This flexibility provides potential for an earlier finish of Contract 4, and potential float in the schedule for other previous contracts (Contract 2a and Contract 3) to finish later without impacting the Plant 3 and 4 completion date of end of 2017.


In Construction Stage 5, Contract 4 continues to be under construction.


In Construction Stage 6, Contract 4 continues to be under construction and Contract 3b is under construction. Important considerations in this construction stage include: The Contract 3b contractor can utilize parking and laydown areas previously used by Contract 2 and Contract

3a; these locations would be sufficient in size, but are not ideal in location as they are not close to the contract limits of Contract 3b.

The construction of the flow splitting chamber and associated piping to Plant 2, 3, and 4 will block access to interior plant roads north and west of the primary clarifiers.

Under Contract 3b, secondary effluent channels would be constructed to connect Plant 2 secondary clarifiers to the tertiary filtration building. A bulkhead to allow connection to Plants 3 and 4 would also be provided to allow an easy connection into the tertiary filtration building

Contract 3b would be constructed at the end of Stage 6; Contract 3b must be constructed prior to commissioning Plants 3 and 4.


In Construction Stage 7, Plants 3 and 4 will be commissioned, allowing for a shutdown of Plant 2 and the construction and commissioning of Plant 2 RAS/WAS pumping station. Contract 4 will be completed at the end of Stage 7.


In Construction Stage 8, Contract 5 will be constructed.

19.3 Process Shutdowns

Table 136 provides an overview of the major process areas which may require a temporary shutdown, bulkheads, or other unique tie in.



Table 136 Potential Process Shutdowns Plant Area Process or

Structure Shutdown Issue Duration1

Digested Sludge Transfer Pumping

Secondary Digesters Complex

The secondary digesters will have to be shutdown for several connections (work may take place simultaneously): Digested sludge draw-off from the secondary digesters will be shutdown while piping and

valves on the digested sludge transfer pumps suction line [within the existing secondary digester complex] are being replaced

It may be possible to use the feed line from the former Digesters 1 and 2 to continue to withdraw sludge from the digesters but temporary trucking and/or dewatering will be required to remove sludge from the site

Digested sludge and pumping from the booster station to WWRMC will be shutdown while piping modifications are being made in the Abandoned Diversion Chamber.

TBD

Headworks Influent Channel Connect new Headworks Building to existing influent channel. TBD Headworks/ Primary Clarifier

Primary Clarifier Influent Channel

Connect new Headworks Building to existing primary clarifier influent channel TBD

Primary Clarifiers Effluent Channel Connect new flow splitting chamber to the existing primary clarifier effluent channel. TBD

Plant 2 RAS/WAS Pump Station

Connect new pump station to existing piping from Plant 2 secondary clarifiers. Connect RAS discharge piping to existing piping and WAS discharge piping to new common forcemains to new sludge thickening facility and primary clarifiers

TBD

Plant 3 &4 Secondary Clarifiers

Effluent Channel Connect Plant 2 effluent to new effluent channel so as to be a combined flow into the new tertiary treatment.

TBD

Tertiary Treatment/ UV Disinfection Facility

Influent Channel Connect Plant 2 and Plant 3&4 effluent channels to new channel so as to be a combined flow into the new tertiary treatment or UV disinfection facility.

TBD

Digesters Digester Mixing Digesters will need to be taken out of service sequentially for mixing, heating, and cover equipment replacement

TBD

Digesters Gas Handling Connect future gas treatment and cogeneration system to existing or modified gas piping and to new waste gas burner. Connect gas piping to relocated boilers

TBD

Digesters Sludge Suction and Discharge Piping

A temporary sludge transfer pumping chamber to connect with temporary sludge gravity transfer line, emergency sludge overflow line and sanitary pipe using flexible hoses, and temporary pumps to pump digested sludge to the existing Secondary Digester No.4; A temporary digester gas pipe to connect the new waste gas burners with the gas supply pipe to the existing open flare behind the existing Primary Digesters No. 5& 6

TBD

Digesters Secondary Digesters

One of the secondary digesters will have to be taken off-line while digested sludge suction piping is replaced within the secondary digester

TBD

Thickening Building Piping Connect existing primary sludge and new WAS pipelines into new thickener building. TBD

Thickening Building Piping Connect new thickened sludge piping in to modified or existing primary digester feed piping at existing chamber in the vicinity of the new thickening building

TBD

TBD Thickening Filtrate Piping Connect to new primary clarifiers effluent flow splitting chamber TBD Centrate Piping Connect to new flow splitting chamber TBD Plant Service Water

Piping Connect to existing Plant Service Water piping main to feed various buildings and process areas.

TBD

Energy Center Plant wide shutdown

To accommodate Switchover of power connection from existing configuration (13.8kV Primary Outdoor Switchgear to Existing Outdoor Substation) to new configuration (13.8kV Primary Outdoor Switchgear to New Energy Center to Existing Outdoor Switchgear)

TBD

Note: 1. Shut downs will be limited to 4 hours where possible

19.4 Contract specific Tie-Ins

This section describes the major contract specific tie-ins, construction sequencing requirements and constraints that will impact plant operations.




Given that there is only one (1) suction and one (1) discharge pipe for digested sludge transfer pumping, it will be necessary to install temporary pumping and potentially temporary on-site digested sludge dewatering during the construction period. Installation of the new forcemain connection and electrical service in advance would reduce the total downtime. This work must be completed prior to decommissioning of the lagoons. New 300 mm ductile iron (DI) sludge transfer mains will be installed from the secondary digester to the existing pump room and from the Digested Sludge Transfer Pump Station to the west to connect to the existing 400 mm HDPE sludge forcemain to the WWRMC in the “abandoned” diversion chamber. The specific route will depend upon potential conflicts with existing piping. This work will be coordinated with the operation of the existing booster pumps operation. The connection will be designed to allow the operation of both systems (not simultaneously) during the decommissioning of the existing sludge lagoons. Connections for temporary pumping, new permanent suction connection and connection to the existing transmission main will require temporary shutdowns of those systems for up to several days.

19.4.2 Contract 2a – Energy Centre

Currently, the Existing Outdoor Substation, and Plant 2 Blower Building Substation (KITSWG02) are fed from the 13.8kV Primary Outdoor Switchgear (KITSWG01). When the Energy Centre (KITSWG03) is built, Existing Outdoor Substation and Plant 2 Blower Building Substation will be fed from the Energy Center, and the Energy Center will be fed from 13.8kV Primary Outdoor Switchgear. In order to accommodate this switchover in power distribution, and to maintain Plant operations without shutdown of power, Plant 2 Blower Building Substation and Existing Outdoor Primary Switchgear construction sequences are required.

19.4.2.1 Electrical Construction Sequencing

Electrical staging drawings are contained in Appendix P. The electrical construction sequence is as follows: 1. Install the new 13.8 kV switchgear KIT-SWG03 in the energy center. 2. Install new ductwork to the

a) existing primary switchgear KIT-SWG01, and b) existing outdoor 600V substation and pull new 13.8 kV conductors.

3. Start-up the new emergency power generation system and commission the new 13.8 kV KIT-SWG03 without connection to the utility main feeders. Utilize load banks for start-up and commissioning of generators.

4. Electrical Connections a) Disconnect one of the utility feeders to the existing outdoor 600 V substation from the primary

switchgear KITSWG01 b) Connect to one of the KIT-SWG03 buses

i. Make connection to the existing outdoor 600V substation bus from KIT-SWG03 ii. During the changeover period, the outdoor 600V substation will operate with the tie breaker

closed and plant loads serviced from the outdoor 600V substation will be limited to 2500 kVA.

iii. Note: the 13.8kV feed to substation KIT-SWG02 at the blower building remains in service with exception of time to make power cable terminations.

iv. Time period for transition will be approximately 4 hrs 5. Repeat for transfer of second utility feed to KITSWG-03 and re-feed of second bus of the outdoor 600V SWGR

a) Two crews required: i. One crew makes connections to re-feed the outdoor substation



ii. Second crew makes connections to reroute the incoming utility feed from KIT-SWGR01 to KIT-SWGR03

6. Connect the new 13.8 kV power feed to the existing outdoor 600V switchgear one bus at a time 7. Provide second 600 V fed to the new MCC in the existing administration building 8. Once utility feeders are connected to KIT-SWG03, complete commissioning of KIT-SWG03


The digestion upgrade will be constructed in sequence to maintain one primary digester in service at all times. During construction, the temporary raw sludge supply pipe, which is currently connected to the overflow box of the existing Primary Digester No. 5, will remain as the sludge supply line. Existing Primary Digester No.5 is currently offline and the clean-up of it is expected to be completed by the start of the construction. Therefore, the digester modifications will most likely start with the existing Primary Digester No.6. Both primary digesters are currently operated at 20oC, therefore requiring minimal digester heating requirement. As such, it is possible that the existing boilers have mainly supplied heat for space heating, and most of the collected digester gas beyond the heating requirement has been flared. Therefore, the temporary disconnection of the existing boilers from the existing digester gas header during construction will have minimum impact on digester gas usage. Natural gas will be used for the space heating during construction. A preliminary four stage construction sequence is presented in Appendix A (300-D707 to 300-D710) and is described as follows: Stage 1: Build Temporary Sludge Transfer Chamber and New Waste Gas Burners

New waste gas burners will be built first. The existing digester gas collection pipe from the primary digesters will be disconnected from the existing digester gas header to ease the construction of the building extension. The digester gas will be sent to the existing open flare, which is behind the two primary digesters. In case the open flare does not have enough capacity to burn all digester gas, a temporary gas pipe will be built to connect the new waste gas burners with the existing gas supply to the open flare. Excessive digester gas will be burned in the new waste gas burners. To ease the new building construction and the relocation of the existing Manhole No.2, a temporary sludge transfer chamber will be built. This chamber will be temporarily connected to the existing sludge gravity transfer pipe, emergency sludge overflow pipe and sanitary pipe using flexible hoses. Submersible pumps will be used to temporarily pump digested sludge from this chamber to the existing Digester No. 4, the existing sludge holding tank. Digested sludge transfer pumps in the existing administration building will withdraw digested sludge from the existing Digester No.4. Stage 2: Build New Building Extension and Upgrade Existing Primary Digester No.6 and Existing Secondary Digester No.3

Once the temporary sludge transfer chamber pumping system and the new waste gas burners and associated temporary piping are in service, the existing Primary Digester No.6 and Secondary Digester No. 3 will be taken off line. Raw sludge supply will be diverted to the existing Primary Digester No. 5 through its overflow box. Digested sludge will flow through the gravity hose to the temporary chamber. During the construction of Stage 2, the Existing Primary Digester No. 5 will remain in service and will not be heated.



Also during Stage 2, the digester control building extension and all proposed equipment including the digester mixing system, sludge recirculation system, sludge transfer system, digester gas handling system, and boiler heating system, and associated yard piping will be constructed Stage 3: Initially Tie-in Upgraded Digesters and Modify Existing Primary Digester No.5

During Stage 3, the existing Primary Digester No. 6 and Secondary Digester No. 3 and associated mixing system, sludge recirculation system, sludge transfer system, and digester gas handling system will be commissioned. Raw sludge will be introduced into the existing Primary Digester No.6 through new sludge supply lines, and digested sludge will be introduced to the existing Secondary Digester No.3 through a new gravity transfer line. Digested sludge transfer pumps will withdraw the digested sludge from the existing Secondary Digester No.3. The waste gas burners will be connected with the new gas header. The temporary chamber will be disconnected from the sludge gravity transfer line, emergency overflow, and sanitary pipes. The new open flare behind the primary digesters will decommissioned. At this stage, the existing Primary Digester No. 5 will be taken offline for proposed upgrades. The existing Secondary Digester No.4 will be abandoned. Stage 4: Tie-in Upgraded Existing Primary Digester No. 5 and Complete Full Commission of Upgraded Digestion System

Once the existing Primary Digester No.5 is ready for commissioning, it will be integrated with the digestion system.

19.4.4 Odour Control

To prevent odour emissions, both of the OCSs should be constructed and operable prior to initial operation of the associated headworks and thickening facilities.


The new Headworks Building will be constructed completely off-line with minimum impact to existing operation. The existing twin inlet channels incorporate isolation gates and bulkhead provisions that can be used to convey wastewater to the new Headworks Building with no effect on the existing system. During staged construction, the existing 1.8 m wide twin channels will be replaced with 2.5 m wide channels, in order to accommodate two new Parshall flume flow meters, which are designed to measure the plant flow up to 430 MLD. A preliminary construction sequence is presented as follows: Stage 1: Construction of New Headworks Building

During Stage 1, the new Headworks Building will be constructed offline, following the decommissioning of the existing sludge lagoon. One (1) of the two (2) existing twin inlet channels will be extended to the new headworks in preparation for tie-in. The new channel extension, immediately downstream of the influent channel split chamber, will be 2.5 m wide. A new effluent channels from the vortex grit separators will tie into the existing primary clarifier distribution channel, but flow will be blocked until the new headworks facility is ready for commissioning. Stage 2: Initial Tie-in



During Stage 2, the new headworks facility will be ready for commissioning. Flow will be introduced to the headworks by opening the corresponding inlet channel gate at the influent channel split chamber. Effluent from the Headworks Building will be diverted to the existing primary clarifiers through the new effluent channel completed in Stage 1. Stage 3: Commissioning of New Headworks Building

During Stage 3, when the new headworks facility is fully commissioned, flow to the existing headworks facility will be cut off by closing the corresponding inlet sluice gate at the influent channel split chamber. Once the existing headworks facility is isolated, the second influent channel will be constructed and tied into the new headworks facility. Stage 4: Decommission of Existing Headworks Building

During Stage 4, the existing headworks facility and detritors will be decommissioned and demolished. A new pilot plant facility will be constructed on the site of the existing headworks facility.

19.4.6 Contract 3a – Tertiary Treatment

The new tertiary filtration facility will be constructed completely off-line with minimum impact to existing operation. The only tie-ins are to the upstream secondary clarifier effluent conduits and the inlet of the UV disinfection facility. A channel stub-out and bulkhead is available at the inlet to the UV disinfection building to facilitate tie-in of the tertiary effluent channel. The new Plant 3 and 4 secondary effluent channel will be constructed with bulkheads to allow simplified connection of the new Plant 2 secondary clarifier diversion conduit and to feed the new tertiary treatment facility. The Plant 2 secondary effluent tie-ins will require the shut-down of two (2) secondary clarifiers at a time (i.e., half of Plant 2 secondary clarifiers) and could be completed when the secondary clarifiers are off-line for replacement of the secondary clarifier mechanisms. The new tertiary facility is planned to be constructed concurrently with Plants 3 and 4. With Plants 3 and 4 commissioned, the Kitchener WWTP will have sufficient capacity to treat all plant flow with two of the Plant 2 clarifiers off-line. If the tertiary treatment facility is accelerated in schedule (i.e., ahead of Plant 3 and 4), an alternative construction sequencing strategy could be developed for the Plant 2 tie-in based on a combination of temporary bulkheads and/or temporary pumping.

19.4.7 Contract 3a – Outfall

The new outfall will be comprised of two (2) sections: one (1) section on land and one (1) section in the river.

The first section will involve the installation of the outfall pipe on land using conventional an open-cut approach.

The second section will involve the installation of the outfall pipe/diffuser in the river. This work will be carried out in stages. During the first stage, a coffer dam will be constructed immediately upstream of the new outfall pipe alignment but sufficiently downstream of the existing outfall to permit continued operation of the existing outfall. The new outfall will be installed within a partial trench and the area will be restored. Once the new outfall is put into service, a second coffer dam will be constructed upstream and the existing outfall structures within the river will be removed and the area restored.



19.4.8 Contract 4 – Secondary Treatment

19.4.8.1 Primary Effluent Flow Splitting and Primary Effluent Channel Upgrade

Primary treatment at the Kitchener WWTP consists of four (4) rectangular primary clarifiers – Primary Clarifiers No. 1 to 4 from north to south. Currently, primary effluent flows to Plant 1 and Plant 2 are discharged from collection chambers at each end of the channel – immediately west of Primary Clarifier No. 4 and No. 1, respectively. When Plant 3 and 4 are constructed, primary effluent flow will be diverted to the new primary effluent flow splitting chamber north of Primary Clarifier No. 3. Refer to the Flow Splitting Chamber drawing 500-D140 for illustration. The existing primary clarifier effluent channel will be upgraded as part of Contract 4 in order to 1. accommodate the construction of the new primary effluent flow splitting chamber for flow distribution to Plants 2,

3 and 4, and 2. increase flow conveyance capacity to prevent flooding of primary clarifier weirs during peak instantaneous flow

conditions.

The effluent channel section immediately adjacent to Primary Clarifiers No. 2 and 3 are to be widened from 1.2 m to 1.5 m and the channel invert deepened by 1.62 m from the current elevation at 283.86 m to 282.24 m. To facilitate the channel upgrade and flow splitting chamber construction, while minimizing the interruption to existing plant operation, the following construction sequence will be adopted: Stage 1: Construction of Flow Splitting Chamber & New Primary Effluent Channel at Primary Clarifier No. 3

A new deeper and wider primary effluent channel section west of Primary Clarifier No. 3 and a flow splitting chamber will be constructed offline. Upon completion of the new channel and flow splitting chamber, the primary effluent channel section will be isolated using stop-logs. The existing channel wall and base slab will be removed, allowing future flow to enter the new channel section and flow splitting chamber. During the isolation period, Primary Clarifier No. 3 will be out of service. Effluent from Primary Clarifier No. 4 will be diverted to Plant 1 and effluent from Primary Clarifiers No. 1 and 2 will be diverted to Plant 2. At the end of Stage 1, flows can be diverted to Plant 3 and 4 through the new flow splitting chamber, and Plant 2 through the existing chamber north of Primary Clarifier No. 1. With the commissioning of Plant 3 and 4, flows to Plant 1 will no longer be required. Stage 2: Construction of New Primary Effluent Channel at Primary Clarifier No. 2

A new deeper and wider primary effluent channel will be constructed and connected to the section west of Primary Clarifier No. 2. During the isolation period, Primary Clarifier No. 2 will be out of service. Effluent from Primary Clarifiers No. 3 and 4 will be diverted to Plant 3 and 4, and effluent from Primary Clarifiers No. 1 will be diverted to Plant 2. Stage 3:

All flows will be diverted to Plant 3 and 4 through the new flow splitting chamber, while the flow to Plant 2 would be shut off temporarily. The shut-off is required such that the flow splitting chamber effluent can be tied into the Plant 2 influent pipe. At the end of Stage 3, all flows from primary clarifiers will be distributed to Plants 2, 3 and 4 through the new flow splitting chamber.



Consideration should be given to performing the primary clarifier upgrades at the same time as the effluent channel and flow splitting works to reduce the total time that the clarifiers are out of service.

19.4.8.2 Blower Building

The following construction sequence will be used: 1. Construct and commission Plant 3 and 4. Five (5) new blowers will be installed in the Blower Building as part of

Contract 4. In this scenario, the blowers will provide lower than design air capacity, as Plant 3 and 4 will require Six (6) blowers.

2. Shutdown Plant 2 to allow for the completion of Plant 2 RAS/WAS pumping station (Plant 2 will require a shutdown to provide final tie-ins which will require a shutdown duration of approximately 2 months). In this stage, If future growth dictates a higher treatment capacity, Plant 1 and Plant 3 and 4 can operate to provide a combined average day treatment capacity of 100 MLD.

3. Commission Plant 2 RAS/WAS pumping station and bring Plant 2 back online. 4. Once Plant 2, 3 and 4 are operational, Plant 1 can be decommissioned. The two (2) existing Plant 1 blowers

located in the temporary blower enclosure will be connected to the five (5) operating blowers without disruption to the Plant 3 aeration tank operation. When the blower tie-in is completed, operations of Plant 3 and 4 secondary treatment can take place at design capacity. If future growth does not require additional treatment capacity provided by Plant 1, the two existing blowers could be relocated to feed Plant 3 and 4 in Step 2 above.

19.4.8.3 Plant 3 and 4 Aeration Tanks and RAS/WAS Pumping Stations

The Plant 3 and 4 aeration tanks are totally independent of the existing structures and can be constructed and commissioned independent of the current plant operation. The RAS/WAS pumping stations will be located adjacent to the effluent channel of the aeration tanks and will share a common wall and base slab with their corresponding aeration tank. Their location requires decommissioning of the sludge lagoons prior to start of construction.

19.4.8.4 Plant 3 and 4 Secondary Clarifiers

The Plant 3 and 4 secondary clarifiers are totally independent of the existing structures and can be constructed and commissioned independent of the current plant operation. Their location requires decommissioning of the sludge lagoons prior to start of construction. Connection to the new Plant 3 and 4 aeration tanks is also totally independent of the remaining structures and can be constructed and commissioned independent of current plant operation. The secondary clarifier effluent channel can be constructed independent of the current plant operation but will need to be connected to the new filtration facility or the UV disinfection facility combining with the Plant 2 secondary clarifier effluent flow. As described in the Contract 3b works, the new secondary effluent channel (to divert flow into the new tertiary filtration building) will be constructed with bulkheads to allow simplified connection of the new Plant 3 and 4 secondary effluent channel.

19.4.8.5 Plant 2 RAS/WAS Pumping Station

The Plant 2 RAS/WAS Pumping Station will be situated on the site of the existing Plant 2 screw pumping station. This concept allows Plant 2 to maintain full operation for most of the construction period, although a one (1) to two (2) month shut down would be required to complete piping tie-ins. Plant 3 and 4 are required to be online prior to a shutdown of Plant 2. Stage 1: Temporary RAS/WAS pumping

Temporary submersible pumps (other temporary pumping systems would also be considered) will be dropped into the existing wet well/chamber at the foot of the screw pumps and used to pump RAS/WAS via temporary pipelines.



Stage 2: Demolition of existing screw pump station

The existing screw pumping station (adjacent to the existing wet well/chamber at the foot of the screw pumps) will be decommissioned and demolished. Stage 3: Construction of new Plant 2 RAS/WAS pump station

The new Plant 2 RAS/WAS pumping station will be constructed on the former site of the screw pumping station and tie-ins made to existing RAS chamber and newly constructed WAS forcemains. Stage 4: Connection of activated sludge lines from Plant 2 secondary clarifiers

Plant 2 will be taken offline for 1 to 2 months to tie in the new pumping station to the existing activated sludge lines from the Plant 2 secondary clarifiers.


The new sludge thickening facility will be constructed completely off-line with minimum impact to existing operation. This facility will be constructed on the site of the abandoned digesters used as temporary sludge holding tanks, located west of the boiler building and south of the primary digesters. A preliminary construction sequence is presented as follows: Stage 1: Construction of New Thickening Building

The site preparation work will be completed as part of Contract 2. In Stage 1, the new Thickening Building will be constructed offline. Stage 2: Initial Tie-in

In Stage 2, WAS from Plant 3, and primary sludge, will be tied-in to the new Thickening Building and the facility will be ready for commissioning. Flow will be introduced to the facility by opening the corresponding valves to feed WAS to the WAS Holding Tanks and primary sludge to the Thickened Sludge Holding Tanks. Thickened WAS and primary sludge from the facility will be pumped to the anaerobic digesters. Thickening filtrate will be pumped back to the primary effluent flow splitting chamber. Primary sludge/scum tie-in to the Thickened Sludge Holding Tanks at the Thickening Building will be made once Thickening Building is constructed.

19.4.10 Miscellaneous Works: Primary Clarifiers

The existing primary clarifiers will be retained. The new headworks facility will need to be connected to the existing primary influent channel without disruption to the existing headworks connection. Stop logs will be utilized to facilitate the connection of new Headworks into the existing primary clarifier distribution channel during staged construction. The primary effluent flow splitting chamber will be connected to the primary effluent channel. The existing connection to Plant 1 will remain in place until after the commissioning of Plants 3 and 4.

19.5 Hydraulic Considerations

There are several areas that will require special consideration during design to ensure the gravity flow and adequate control of flow splitting between various treatment processes.



19.5.1 Contract 3a – Headworks Discharge

The new Headworks facility effluent channel will have to be connected to the existing Primary Clarifier influent channel while the existing headworks and primary clarifiers remain in service. This connection will have to be done in such a way as to ensure equal flow split between the four primary clarifiers. Consideration will also have to be given to making allowance for the possible future addition of new primary clarifiers should treatment capacity have to be increased at some point in the long term future. New primary clarifiers would likely be constructed in the location of the existing Plant 1 secondary treatment.

19.5.2 Contract 3a – Tertiary Treatment

The Tertiary Treatment Facility will impose a significant headloss on the overall plant hydraulics. The specific requirements will be dictated by the equipment selected and the facility layout. The preliminary design was based on conservative estimates; the estimates are to be confirmed detailed design so that the appropriate measures can be incorporated in the design to avoid any potential need for pumping. New effluent channels and diversion chambers will be required to direct the flow from Plant 2 secondary clarifiers to the Tertiary Treatment facility. Depending on the hydraulic profile, it may be more appropriate to increase peak flow throughput for Plant 3 and 4, rather than try to handle a peak event through Plant 2. This will be evaluated during detailed design. To accommodate the associated with the new tertiary filtration facility based on the current Aquadisk® design, two modifications are recommended for Plant 2 secondary clarification, as follows: Provide a new secondary effluent channel for two of the Plant 2 secondary clarifiers to reduce peak flow in the

Plant 2 secondary effluent channel Raise the Plant 2 secondary clarifier launder by approximately 200 mm, which can be easily accommodated

during the planned replacement of Plant 2 secondary clarifier mechanisms. Due to the head differential between the existing aeration tanks and secondary clarifiers, the increase in weir elevation will have minimal impact on internal Plant 2 hydraulics.

Overall, these modifications allow the new tertiary filtration system to accommodate design peak flow events while maintaining approximately 200 mm freeboard at the Plant 2 secondary clarifiers. These modifications may or may not be required with other equipment technology. Plant 2 modifications should be completed before or during the construction of the tertiary treatment facility to provide adequate hydraulic buffering capacity.

19.5.3 Contract 4 – Primary Clarifier Effluent Flow Splitting

Hydraulic analysis was performed for the Kitchener WWTP upgrades at Plant 2 and Plant 3 and 4. The analysis identified a bottleneck at the existing primary effluent channel, which is 1.22 m in width and 1.63 m in height (1 m to primary clarifier weirs). Under the peak instantaneous flow (PIF) condition of 430 MLD (215 MLD in each half of the channel), excessive headloss would cause flooding of primary clarifier weirs and risk overflowing the primary tanks. In order to improve the hydraulic conditions, the primary effluent channel is being upgrades as part of the miscellaneous upgrades.

19.6 Demolition


In order to provide adequate upgrades to reliably pump digested sludge from the Kitchener WWTP to the WWRMC, the following facilities will be decommissioned and demolished: Secondary Digester Complex

o All piping (exterior of the Secondary Digester) associated with transfer of digested sludge to the Digested Sludge Transfer Pump Station



Digested Sludge Transfer Pump Station o Suction piping o Pumps o Discharge piping, up to and including flow meter o HVAC demolition as per drawings

Storage Room o Storage cabinets o Staircase and platform

Yard Piping o Pump suction piping from the secondary digester complex to the Digested Sludge Transfer Pump

Station o Pump discharge piping from the Digested Sludge Transfer Pump Station to the valve chamber

19.6.2 Contract 4 – Plant 2 RAS/WAS Pumping Station

The Plant 2 RAS/WAS Pumping Station will be demolished after the commissioning of Plant 3 and 4 to provide the required footprint for the construction of the new Plant 2 RAS/WAS pumping station.


In order to provide space for the new Energy Center at the Kitchener WWTP site, abandoned digesters used as temporary sludge holding tanks, located west of the boiler building and south of the primary digesters, and the adjacent abandoned process tanks will be demolished.

19.6.4 Miscellaneous Works – Plant 1

As part of the miscellaneous upgrades, Plant 1 structures will be demolished, as described in Section 16.5.

19.7 Constructability Review

An independent constructability review was performed during the preliminary design phase by a team of construction services engineers and site staff. The purpose of the constructability review was to evaluate the preliminary design from the perspective of a Contractor, and identify construction related issues to be addressed by the design team. A review comments and disposition table, presented in Appendix P, was generated during the constructability review. Some of the review comments have been incorporated into the preliminary design and others will be addressed during detailed design. The comment and disposition table will be updated and revisited at various stages of detailed design.

19.8 Design and Construction Plan and Schedule

19.8.1 Equipment Pre-Selection Plan

Equipment pre-selection and/or pre-purchase offers a number of advantages to the Owner, particularly for large complex projects with multiple Contracts and critical scheduling. Considerations include: Compatibility with existing equipment – provides a number of benefits, including operator familiarity with

equipment and the ability to have common spare part; Equipment delivery – for many larger pieces of equipment the delivery time is 26 to 40 weeks after approval of

shop drawings, which represents a significant portion of the total contract period. Pre-selection (and approval of shop drawings) allows the Contractor to order the equipment sooner and reduces the risk of cascading delays

Equipment quality – pre-selection allows the Owner to conduct an evaluated bid to ensure the equipment supplied provides the best overall value. The equipment installed is expected to have a life of between 20 and



30 years and provide a high level of performance and reliability. A Contractor bidding will choose cheaper equipment in order to win the project, which may not be better for the Owner over the life of the equipment.

Approvals – some equipment requires regulatory approvals that can require a significant amount of time to obtain (in particular air approvals) and may be equipment specific. Waiting for the equipment to be selected by the Contractor prior to obtaining approvals can impact the construction schedule

Design efficiency – equipment configuration can impact the layout of a building, spacing and in particular pipe layout. Having detailed drawings of the equipment can facilitate detailed design and reduce conflicts during construction due to unexpected equipment requirements.

In addition to the above typical considerations, the Region operates a number of facilities and is currently implementing a major upgrade of the Waterloo WWTP, which involves much of the same equipment as will be installed at the Kitchener WWTP. Selection and installation of similar equipment would provide a long term benefit to the Region. Three options for equipment selection have been considered: 1. Sole source – identify a single supplier/manufacturer to provide equipment based on project specific

requirements that cannot be satisfied by any other supplier/manufacturer. Must clearly identify reason. In most cases, equipment would be pre-purchased by the Region.

2. Pre-selection/Pre-purchase – evaluated bid process in which a minimum of three suppliers/manufacturers are invited to submit bids based on a formal bidding process including financial conditions and technical specifications. Evaluation process is clearly identified in Bid Documents. Key benefits are the ability to have full control over equipment selected, reduced delivery time, improved design/construction co-ordination. Equipment may be pre-purchased if required for project schedule. As a minimum the Region should pre-purchase the shop drawings in order to facilitate design and minimize any potential impacts on construction schedule

3. Post selection – name three equipment manufacturers in the general contract tender document and have the contractor base their bid on the first named. During the shop drawing review stage, the Contractor would have the option to propose one of the alternatives by demonstrating an advantage to the Region (e.g., cost, delivery, quality other construction benefits).

The Region’s preferred approach for Construction projects is “Post-Selection”. Table 137 presents items of major process equipment that would normally be considered for either pre-selection or pre-purchase. The table identifies the recommended process and provides reasons for recommendation. The default recommendation is the Region’s preferred approach (post-selection) with the equipment currently being installed at the Waterloo WWTP as the first named unless there are reasons to indicate otherwise. Using the first named from the Waterloo WWTP offers the benefit of the equipment already having been through a post selection evaluation and proving the Region with similar equipment at two facilities.



Table 137 Major Equipment Pre-Selection Recommendation Item Recommendation Basis

Aeration Blowers Sole Source, Pre-purchase

2 of 7 blowers required will be transferred from Plant 1 Similar to Plant 2 blowers (5 blowers) Similar to Waterloo WWTP blowers (6 blowers)

Bar Screens Post Selection Specify same equipment as Waterloo WWTP, first named to be equipment installed at Waterloo Can have impact on building configuration

Grit Removal Equipment

Post Selection Specify same equipment as Waterloo WWTP, first named to be equipment installed at Waterloo

Aeration Diffusers Post Selection Specify same equipment as Waterloo with first named to be vendor used for Kitchener Plant 2 to provide consistency at Kitchener WWTP.

Secondary Clarifier Mechanism

Post Selection Quality of equipment

Tertiary Filtration

Disc Filters

Pre-selection,

Pre-purchase

Equipment is unique. Building size and configuration is equipment specific Pilot study will be conducted to identify appropriate equipment – this should be used as the basis for pre-

selecting equipment Timing is not critical so pre-purchase may not be required as long as shop drawings are pre-purchased

Rotary Drum Thickeners

Post Selection Specify same equipment as Waterloo WWTP, first named to be equipment installed at Waterloo

Digester Mixing Equipment

Post Selection Specify same equipment as Waterloo WWTP, first named to be equipment installed at Waterloo This equipment will require review once the system has been commissioned in Waterloo as a custom system may be provided.

Digester Gas

Cover

Pre-selection,

Pre-purchase

Equipment is unique. Site specific installation requirements may be require Equipment is relatively new to Ontario and will require TSSA approvals which could impact design requirements, construction schedule and costs

Equipment delivery itself is not long so pre-purchase may not be required as long as shop drawings are pre-purchased to facilitate regulatory approvals

Boilers Post Selection Specify same equipment as Waterloo WWTP, first named to be equipment installed at Waterloo

Primary Digester

Covers Post Selection Specify same equipment as Waterloo WWTP, first named to be equipment installed at Waterloo

Standby Generators

Sole Source, Pre-purchase

Very large standby generators Equipment requirement is identical to Waterloo Air approvals requires modeling of specific generators – could impact schedule Relatively long delivery time

Completion of energy centre is required in order to commission Contract 2b (Anaerobic Digestion) and Contract 3a (Headworks)

Energy Centre MCCs/Switchgear

Pre-selection, Pre-purchase

Very long delivery time (>40 weeks with shop drawing approval) Completion of energy centre is required in order to commission Contract 2b (Anaerobic Digestion) and Contract 3a (Headworks)

19.8.2 Risk Assessment

A complex project of an existing operational WWTP that takes place over a long period of time presents many risks. This section identifies some of the key risks that can be expected in the Phase 3 upgrades of the Kitchener WWTP. Some of these risks can be managed through additional studies, contract document wording, coordination amongst the various parties and early/frequent regulatory agency consultation. However, some of these risks are beyond the control of the Region and will have to be dealt with when encountered.



19.8.2.1 Capital and Operating Costs

19.8.2.1.1 Capital Costs

Capital cost estimates have been prepared at a point in time, however, the work will be carried out over a period of greater than 10 years. Uncertainty associated with many of the assumptions made at this stage can impact the actual cost significantly. The cost estimate will be regularly reviewed and updated during detailed design to assure that, as the design is developed, that the cost impacts of the design development are identified, quantified, and evaluated. Some specific areas of uncertainty include: Lagoon Decommissioning – studies have been conducted to characterize lagoon materials, however, there are

still significant gaps and uncertainty, especially with respect to the extent of contamination and potential groundwater management requirements. Regulatory approval still has to be negotiated.

Connection to Existing Facilities – in several areas, connection to existing facilities is required. This can often lead to unanticipated costs due to temporary or difficult construction.

Construction Materials – materials of construction costs have been subject to much greater variations in the past several years than in any recent time. Prices for such basic materials as steel, aluminum, copper, cement, and plastic have been subject to sometimes wildly dramatic changes due to disasters, shortages, or other supply issues. Cost changes due to these changes cannot be estimated, especially at this early stage of the project.

Economy and Competition – in many areas, the depressed economy has had a beneficial impact on project costs, increasing competition and resulting in lower tender prices. Conversely, multiple similar projects in a limited geographic area, especially if large enough to limit availability of suitable contractors, can result in increased capital costs.

Labour – costs are linked to the economy and competition and could vary depending upon the demands on the local workforce, especially the skilled trades.

Maintaining Plant Operation – it is difficult at this stage of a project to fully anticipate the cost and effort required to maintain the existing treatment plant in operation during construction. Many factors including construction sequences, access, and availability of ancillary systems can impact these costs in ways unanticipated at this time.

19.8.2.1.2 Operating Costs

Operating costs have been estimated based on the conceptual process design. As more detailed design is developed, more detailed information and anticipated operating procedures will become available, resulting in better defined operating costs.

19.8.2.2 Community Impacts

The community will be impacted by this project. Community concerns relate to odours, noise and truck traffic. While odours will be greatly improved in the long term, there may be short term negative impacts, especially during lagoon decommissioning. The construction project will result in increased traffic.

19.8.2.3 Schedule

The major schedule risk is the time required to obtain approvals from government agencies, especially the MOE. The time for review and approval of tender documents is long and careful consideration of that time needs to be factored into the overall design and construction schedule. Also, as addressed in the Capital and Operation Cost risk assessment, the time required for construction, especially when impacted by maintaining plant operations and plant interconnections can often create construction sequencing challenges and delays.



19.8.2.4 Risk Register

Appendix Q contains an initial Risk Register for the Phase 3 WWTP upgrades project. This register was developed during the Site Wide Facility Plan stage and will be maintained and updated throughout the project.



20. Project Cost Estimate 20.1 Construction Cost Estimate

20.1.1 Cost Summary

The preliminary total project cost, presented in Table 138, is presented by contract. Table 138 Summary of Project Costs

Item Description Contract 1 Contract 2 Contract 3 Contract 4 Contract 5 & Misc. Upgrade

Total Project Cost

SUB TOTAL $13.60 M $28.90 M $44.10 M $61.30 M $32.60 M $180.50 M Estimating Allowance $2.72 M $5.78 M $8.82 M $12.26 M $6.52 M $36.10 M Contractor Overhead/Profit $2.45 M $5.20 M $7.94 M $11.03 M $5.87 M $32.49 M Construction Contingency $0.94 M $1.99 M $3.04 M $4.23 M $2.25 M $12.45 M CONSTRUCTION COST TOTAL $19.7 M $41.9 M $63.9 M $88.8 M $47.2 M $261.5 M Engineering1 $2.36 M $5.03 M $7.67 M $10.66 M $5.67 M $31.39 M Region Staff Fee1 $0.39 M $0.84 M $1.28 M $1.78 M $0.94 M $5.23 M PROJECT COST TOTAL $22.5 M $47.7 M $72.8 M $101.3 M $54.0 M $298.3 M Note: 1. Based on Region of Waterloo Wastewater Design Standard 52005 (Region of Waterloo, 2009)

Each of the contract cost estimates includes: 20% for Estimating Allowance 15% for General Contractor’s (GC) Overhead/Profit 5% for Construction Contingency 12% for Engineering, and 2% for Region Staff Fee.

For the purposes of this report, the cost estimates provided in Table 138 have been shown in 2012 dollars. Escalation to the year of construction has not been included, however, the Region’s capital planning model takes this into consideration. The total cost estimate of $298 M is consistent with the Site Wide Facility Plan estimate of $296 M, which did not include the Region cost of 2% (required in all Preliminary Design Cost estimates, based on Based on Region of Waterloo Wastewater Design Standard 52005 - Region of Waterloo, 2009). Detailed cost estimates for each contract are provided in Appendix R.

20.1.2 Cost Estimating Basis/Assumptions

Appendix R contains a detailed calculation of cost estimating worksheets for each contract. In addition to contractor markups, estimating allowance, construction contingency, engineering and regional fee, the preliminary project costs were prepared based on the following: Assumptions

Normal construction (i.e. 5 days/week at 8 hours/day, 40-hour working week) Cost estimated in March 2012 dollars Unit prices and equipment costs are based on quotations, cost books and historical data from recently

tendered WPCP projects with allowance for installation Process mechanical allowance for piping and ancillary systems Retrofit allowance for building renovations and facilities that require significant tie-ins to existing facilities



Site civil allowance for storm water management, drainage pipes, roads, and etc. Demolished materials/soil to be removed offsite Onsite dewatering of Lagoon decommissioning and addition amendment due to time constraint

Exclusions HST Cost is not presented in the year of construction Impacts due to inflation and escalation Removal of unknown hazardous wastes Non-competitive market conditions (i.e. shortage of materials, shortage of skilled labour & etc.) Additional cost for approaches to accelerate the construction Recycling/Reuse of disposal materials/soil (Disposal materials/soil to be determined if they are applicable for

recycle or reuse).

20.1.3 Cash Flow Projection

Using a design fee estimate of 6% and the schedule provided in Appendix R, the costs for engineering and construction were allocated to the months in which the occur as per the schedule. Table 139 and Figure 27 provide the cash flow projection by year from the start of Detailed Design and Tendering through completion of the final contract. The cash flow projection shows an apparent drop in spending during 2015. This drop is the result of the expedited completion of Contract 2a (Energy Centre) and the built in float between Contract 3 and Contract 4. In actual fact, the capital spending over the years 2014 through 2017 is expected to be relatively consistent at around $45 M per year. Table 139 Projected Annual Cash Flow for Kitchener WWTP Upgrades

Year Capital Spending 2012 $4,960,000 2013 $32,682,000 2014 $54,054,000 2015 $35,552,000 2016 $52,952,000 2017 $50,114,000 2018 $31,505,000 2019 $24,320,000 2020 $12,160,000

TOTAL $298,299,000 Figure 27 presents the approximate allocation of project cost by year.



Figure 27 Projected Annual Cash Flow for Kitchener WWTP Upgrades

$-

$10,000,000

$20,000,000

$30,000,000

$40,000,000

$50,000,000

$60,000,000

2012 2013 2014 2015 2016 2017 2018 2019 2020

PRO

JECT

ED A

NN

UAL

SPEN

DIN

G

YEAR

Contract 1 = $22.5M

Contract 2B = $28.1M

Contract 2A = $19.7M

Contract 3A = $33.2M

Contract 4 = $101.3M

Contract 5A = $9.4M



Misc. Upgrade = $24.8M



20.2 Operation and Maintenance Cost Estimate

Table 140 presents an overview of estimated annual O&M costs (in 2012 dollars) for the upgraded Kitchener WWTP after the commissioning of the Phase 3 upgrades. Table 140 Operation and Maintenance Cost Estimate

Item Cost Estimate Administration $234,500 Salaries & Benefits $1,145,664 Insurance $267,050 Quality Management/Reporting $12,500 Audit & Legal $75,000 Consultant Fees $67,500 Supplies & Services $49,500 Ferrous Chloride (kg as Fe) $145,000 Ferric Chloride (kg as Fe) $114,950 Sodium Hypo $18,820 Sodium Bisulphite $8,800 Polymer Thickening $229,950 Polymer $520,344 Natural Gas $25,713 Hydro $2,608,169 Fuel $17,045 Water $10,280 Vehicles $24,000 Equipment Maintenance $1,300,000 Building & Structural Maintenance $325,000 Tools, Shop Maintenance $7,500 Solid Waste Disposal $2,031,602 Laboratory Sampling $56,000 RMOW Administrative Costs1 $200,000 TOTAL O&M Estimate $9,295,000 Note: Taxes were assumed to be incorporated into all costs Chemical and biosolids disposal costs include WRMC operation 1. Region Administration costs above those included in specific line items The O&M cost estimate was developed in consultation with the Region and OCWA. The following information was used to develop the O&M cost estimate: The current Operations Contract between the Region and OCWA Historical utility billings/rates provided by the Region Historical chemical consumption and unit rates provided by OCWA Estimated electrical consumption based on new equipment loads and design operating conditions Information provided by CH2M Hill with respect to the upgraded Plant 2 operation Chemical and electrical operating costs for the Manitou WWRMC operation for biosolids disposal Projected staffing plan based on current operating staff and including new staff required to operate the additional

process units Region costs for resources directly attributable to the operation of the Kitchener WWTP



21. Value Engineering The Kitchener WWTP Phase 3 Upgrade Preliminary Design Report was subject to a Value Engineering (VE) study by a multidiscipline team led by a VE facilitator, ARCADIS. The VE team consisted of ARCADIS specialists and its subconsultant team as well as representatives of the Region of Waterloo’s project development team and the Senior Operations Manager from the Ontario Clean Water Agency (OCWA). The VE team identified 26 VE Alternatives with performance and/or cost savings potential and 20 design suggestions that are expected to result in performance improvements, constructability enhancements, and/or non-quantifiable cost savings (ARCADIS, 2012). AECOM reviewed each of the proposed VE Alternatives, taking into consideration the information presented by the VE Team, information considered during the preliminary design that may not have been available to the VE Team, and new information acquired in response to the VE Alternative. Where appropriate, AECOM has also identified revised cost implications. AECOM associated a “Response” to each VE Alternative, using the following categories: Recommended (R), Recommended with Modifications (M), Requires Further Review and/or Region of Waterloo Input (RM); Comment Noted and will be Considered in Detailed Design (C), and Not Recommended (NR). A full overview of the initial review is presented in PDM-8, contained in Appendix C. AECOM’s initial review of, and responses to, the VE Alternatives were presented at the VE Implementation meeting, held on June 27 2012, at which next steps to implement the VE Alternatives were also discussed. Participants in this meeting included representatives from the Region, OCWA, the Design Team (AECOM/CIMA) and the VE Team (ARCADIS). The Design Team made a presentation of the proposed responses to all the VE Alternatives, which were then discussed by all participants and, for the most part, consensus decisions were made as to how to proceed with each Alternative. Three key concepts were discussed in detail at the VE Implementation Meeting: relocate energy centre and sludge thickening, retain Plant 1, and use rectangular secondary clarifiers. An alternative site layout approach was developed, which builds on the concepts developed by the VE team regarding the relocation of the energy centre and sludge thickening building and eliminates the concerns related to future expansion of circular secondary clarification system. This alternative site layout, however, precludes the long term retention of Plant 1. An overview of this concept is presented in Figure 28. The key elements of this concept are as follows: Relocate Energy Center (Contract 2a) to east of the existing boiler building Retain the existing boiler building to service existing buildings as required (until new digester contract complete) Relocate the Thickening Building (Contract 5) to the current site of Plant 1 Locate future liquids expansion build in the current site of Plant 1 (Phase 4 upgrades - beyond 2030) Provides more space and better layout to allow better access to Energy Center and future CHP Provides more space and better layout for future primary sludge thickening expansion (Phase 4 upgrades -

beyond 2030) Allows for “Free Excavation” in Plant 1 Area



Figure 28 Revised Site Plan Based on Relocation of Energy Centre and Thickening Building

A number of decisions required a final decision by the Region or were deferred to detailed design. Prior to the finalization of this PDR, The Region provided feedback on four of the most time sensitive outstanding items, presented in Table 141. Table 141 Region of Waterloo Input on Outstanding Preliminary Design VE Items

VE Alt Outstanding Item Region Decision AECOM Final Disposition

G-1/3 Relocation of Energy Centre and Sludge Thickening buildings

Adopt recommended alternative site layout approach; old digesters to remain in place

NR/M

ST-1 Extension of the life of Plant 1 and reduce the size of new Plant 4 by one-half

Reject in favour of alternative site layout approach; Plant 1 will be demolished as part of Contract 5 and Plant 3/4 will not be reduced.

NR

D-1 Use of LM™ mixers in lieu of the jet mixing system To be determined C

EC-2 Placement of emergency generators in an outdoor acoustical enclosure

Locate generators in outdoor enclosures; determine location of enclosures during detailed design

R

The VE Alternative categorisation was finalized based on decisions made at the VE Implementation meeting and feedback received from the Region in August 2012: 12 alternatives are Recommended (R), 21 alternatives will be considered during detailed design (C) and 14 alternatives are Not Recommended (NR) (two options were included under 2 categories).The final dispositions of AECOM and ARCADIS are presented in Table 142. AECOM and ARCADIS are in general agreement as to the final disposition of most items, although there are minor differences in the specific categorizations used for some items. The only VE Alternative that was categorized fundamentally

1



differently was VE alternative ST-1 (Extend the life of Plant 1 and reduce the size of new Plant 4 by one-half); while AECOM does not recommend this option (NR), ARCADIS indicated that it would be considered during detailed design (C); this option has been subsequently rejected by the Region of Waterloo. It should be noted that AECOM and Arcadis used different designations for the categorization of options. A legend is provided at the bottom of the Table. Of particular note AECOM used “R – Recommended” while ARCADIS used “R – Rejected”. Table 142 Final Recommendations for VE Alternative Implementation VE Alt Description AECOM Final Disposition1 ARCADIS Final Disposition2

G E N E R A L

G-1 Relocate the Energy Centre to the east of the secondary digesters Not Recommended NR Reject R

G-3 Relocate the Energy Centre between the new Headworks facility and new Blower Building

Not Recommended/ Recommended with Modifications

NR/M Accepted Modified AM

C O N T R A C T I N G

C-2 Use an early electrical contract to provide distribution throughout the site Recommended R Accept and Implement A

C-4 Place the primary clarifier connection to the new aeration tanks in the contract for the Headworks Recommended R Accept and Implement A

C-5 Advance the schedule for construction of the Plant 2 RAS/WAS pump station Not Recommended NR Reject R

C-7 Have Secondary Treatment Facility contractor remove the clay layer in Lagoon 1 in lieu of the Lagoon Decommissioning contractor

Consider During Detailed Design C Consider During Detailed Design C

C-9 Perform all final road surfacing in one contract at the end of the project Recommended R Accept and Implement A

C-10 Establish a staging date milestone in Contract 1a that includes construction of the new road into the plant and completion of the south end of Lagoon 1 decommissioning

Recommended with modifications M Accepted Modified AM

C-11 Use a performance contract with an incentive clause for the Lagoon Decommissioning Not Recommended NR Reject R

C-New Pipe from existing primary effluent chambers to new flow splitting chamber Not Recommended NR

H E A D W O R K S H-2/3 Add a sink and work room bench in the Headworks Building Recommended R Accept and Implement A

H-5 Use an alternate material for covers in lieu of concrete for the vortex grit removal structure covers Consider During Detailed Design C Consider During Detailed Design C

H-6 Eliminate the piped standby grit pump in the grit system and provide an uninstalled spare pump Recommended R Accept and Implement A

H-7 Eliminate the channel aeration in the Headworks Building Not Recommended NR Reject R

H-10 Place the chemical (ferric/ferrous) feed pumps on the lower level of the headworks building and delete pump building Not Recommended NR Reject R

H-12 Construct a scale model of the channels and the flow within the channels to identify potential deposition areas Consider During Detailed Design C Consider During Detailed Design C

S E C O N D A R Y T R E A T M E N T

ST-1 Extend the life of Plant 1 and reduce the size of new Plant 4 by one-half Not Recommended NR Consider During Detailed Design C

ST-5 Use eight rectangular secondary clarifiers in lieu of eight circular secondary clarifiers and provide a common mixed liquor channel

Not Recommended NR Reject R

ST-6 Design only one Plant 3 and do not divide it into Plant 3 and Plant 4 Recommended R Accept and Implement A

ST-11 Move the RAS/WAS pump stations for Plants 3 and 4 to the center of each set of four circular secondary clarifiers Consider During Detailed Design C Accepted Modified AM



VE Alt Description AECOM Final Disposition1 ARCADIS Final Disposition2

ST-12 Use one primary aeration tank feed channel in lieu of direct piping to each of the two plants Consider During Detailed Design C Reject R

ST-14 Reduce the number of spare RAS pumps to one per two duty pumps to one per four duty pumps Not Recommended NR Reject R

ST-15 Use groundwater relief valves in lieu of micro piles to prevent uplift of the tanks due to high groundwater Consider During Detailed Design C Consider During Detailed Design C

ST-17 Use invent mixers in lieu of submersible mixers in the anoxic zone of the aeration tanks and delete two baffle walls Consider During Detailed Design C Consider During Detailed Design C

ST-18 Use sludge rings in lieu of deep hoppers for sludge removal in the secondary settling tanks Consider During Detailed Design C Consider During Detailed Design C

T E R T I A R Y T R E A T M E N T

TT-1 Delay the installation of some of the disc filters by designing for a flow of 210 ML/day and reduce size of building Not Recommended NR3 Reject R

TT-5 Design the Tertiary Treatment facility for peak daily flow in lieu of peak hourly flow, reduce the number of filters and reduce the size of the building

Recommended R Accepted Modified AM

TT-6 Relocate the stairwell and electrical room to make the Tertiary Treatment building more expandable Recommended R Accept and Implement A

T H I C K E N I N G B U I L D I N G

T-3 Install only a dry polymer system in lieu of a dry polymer system and a liquid polymer system Recommended R Accept and Implement A

T-4 Consolidate Thickening Building spaces, delete provisions for future primary sludge thickening and reduce the building size Not Recommended C

/NR4 Consider During Detailed Design C

T-7 Move stairwell of the Thickening Building to allow electrical connections between the Energy Centre and Thickening Building

Consider During Detailed Design C Consider During Detailed Design C

D I G E S T I O N

D-1 Use LM™ (linear motion) mixers in lieu of the jet mixing system Consider During Detailed Design C Consider During Detailed Design C

D-4 Move the Thickening Building and combine it with the digester complex Not Recommended NR Reject R

E N E R G Y C E N T E R

EC-2 Place the emergency generators in acoustical enclosures and make the building smaller Region input required R Consider During Detailed Design C

EC-3 Consolidate energy facility spaces and reduce size of building Consider During Detailed Design C Consider During Detailed Design C

EC-4 Reduce the height of some building spaces in the Energy Centre Consider During Detailed Design C Consider During Detailed Design C

EC-8 Provide diesel fuel cleaning for standby generator fuel Consider During Detailed Design C Consider During Detailed Design C

A D M I N I S T R A T I O N B U I L D I N G

AB-1 Consolidate spaces and reduce the patio to make the building smaller Consider During Detailed Design C Consider During Detailed Design C

AB-2 Reduce the height of the Administration Building Consider During Detailed Design C Consider During Detailed Design C

AB-3 Reduce the amount of glazing in the Administration Building Consider During Detailed Design C Consider During Detailed Design C

AB-4 Use alternate building materials for the Administration Building Consider During Detailed Design C Consider During Detailed Design C

AB-5 Use a low albedo roof in lieu of a "green" roof on the Administration Building Consider During Detailed Design C Consider During Detailed Design C

E L E C T R I C A L

E-1 Install aluminum 15 kV cables in lieu of copper Recommended R Accept and Implement A

E-4 Use bypass contactors on variable frequency drives where practical Consider During Detailed Design C Consider During Detailed Design C



VE Alt Description AECOM Final Disposition1 ARCADIS Final Disposition2

E-5 Delete operator controls from the front of the motor control centers Consider During Detailed Design C Consider During Detailed Design C

E-8 Run 15 kV feeders partially overhead in lieu of underground Not Recommended NR Reject R

E-10 Provide an alternate source of power for the aeration blowers Recommended R Accept and Implement A Note

1. AECOM Disposition Categories: Recommended (R), Recommended with Modifications (M), Requires Further Review and/or Region of Waterloo Input (RM); Comment Noted and will be Considered in Detailed Design (C), and Not Recommended (NR)

2. ARCADIS Disposition Categories: Accept and Implement (A), Accepted Modified (AM), Consider During Detailed Design (C), Reject (R) 3. The phasing element of TT-1 will be evaluated further in application of the recommended TT-5, which will be carried forward into detailed design. 4. Consolidate Thickening Building spaces (C), delete provisions for future primary sludge thickening (NR) and reduce the building size (C)

Five options that have been classified as consider during detailed design (C) or recommended (R) require some additional discussion prior to the start of detailed design. These options are as follows: Use invent mixers in lieu of submersible mixers in the anoxic zone of the aeration tanks and delete two baffle

walls (VE Alternative ST-17) (C); Construct a scale model of the channels and the flow within the channels to identify potential deposition areas

(VE Alternative H-12) (C); Move the RAS/WAS pump stations for Plants 3 and 4 to the center of each set of four circular secondary

clarifiers (VE Alternative ST-11) (C); Extent of electrical site distribution (VE Alternative C-2) (R); and Use of LM™ mixers in lieu of the jet mixing system (VE Alternative D-1) (C).

It is critical that decisions on these items be made at the earliest opportunity during detailed design to avoid impacting the schedule and cost. The changes arising out of the Value Engineering were recommended after completion of the Preliminary and therefore are not reflected in the Preliminary Report Design Basis or Drawings. These changes will be implemented, as appropriate, through Detailed Design and Construction.



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Wide Facility Plan Report - FINAL ARCADIS. (2012). Kitchener Wastewater Treatment Plant Phase 3 Upgrades Final Value Engineering Study Report. CANVIRO Consultants (CANVIRO). (1986). Phase II Report: Regional Municipality of Waterloo Liquid Sludge

Management Study. CH2MHill. (2011). Final Report for Region of Waterloo Biosolids Management Master Plan. Prepared for Region of

Waterloo. CH2MHill. (2010). Region of Waterloo Kitchener Wastewater Treatment Phase 2 Upgrades Preliminary Design

Report – DRAFT. CH2MHill. (2008). Odour Assessment and Interim Odour Mitigation Plan for the Kitchener WWTP. Doyle, G.; Seica, M.V.; and Grabinsky, M.W.F. (2003). The role of soil in the external corrosion of cast iron water

mains in Toronto, Canada. Canadian Geotechnical Journal. 40: 225–236. EarthTech. (2008). Region of Waterloo Wastewater Treatment Master Plan Final Report England Naylor Engineering Ltd. (Naylor). (1988). Geotechnical Investigations Region of Waterloo Liquid Sludge

Management Facilities Upgrading of Existing Lagoons and Lagoon Sludge Booster Pumping Station Kitchener Water Pollution Control Plant Kitchener, Ontario.

Ministry of the Environment (MOE). (2008). Design Guidelines for Sewage Works. MTE Consultant, Inc (MTE). (2012). Kitchener-Wastewater Treatment Plant Upgrades, Kitchener, ON, Draft

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Preliminary Design Report Version 2.2. Stantec. (2010). Kitchener Wastewater Treatment Plant Upgrades, Middle-Grand River Assimilative Capacity Study. XCG. (2007). Final Draft Report- Odour Investigation Study at the Kitchener Wastewater Treatment Plant, Kitchener

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