ORANGE COUNTY WATER DISTRICT 18700 Ward Street Fountain ... · Experience shall include installation of a minimum of 10,000 linear feet of sewer rehabilitation with pipe of 48-inch

Orange County Water District Plant 2 Secondary Effluent Addendum No. 3 Pipeline Rehabilitation Page 1 of 3

ORANGE COUNTY WATER DISTRICT 18700 Ward Street Fountain Valley, California 92708-6930 ADDENDUM NO. 3

TO PLANS, SPECIFICATIONS AND CONTRACT DOCUMENTS

FOR PLANT 2 SECONDARY EFFLUENT PIPELINE REHABILITATION PROJECT

CONTRACT NO. GWRS-2020-01

THE BIDDER SHALL EXECUTE THE CERTIFICATION AT THE END OF THIS ADDENDUM AND SHALL ATTACH IT TO THE PROPOSAL SUBMITTED. _________________________________________________________________ ORANGE COUNTY WATER DISTRICT May 26, 20202 Sandy Scott-Roberts, P.E. Date Project Manager THE BIDDER SHALL EXECUTE AND ATTACH THE FOLLOWING CERTIFICATION TO THE PROPOSAL. _________ ___ BIDDER'S CERTIFICATION I acknowledge receipt of the foregoing Addendum No. 3 to Contract No. GWRS-2020-01 and accept all conditions contained therein: Date: _____________________________________________________ Bidder: _____________________________________________________ By: _____________________________________________________


In accordance with Instructions to Bidders, we hereby issue Addendum No. 3, as indicated by the attached sheets. Acknowledge receipt of this Addendum by inserting its number and date on the Bid Form, Item 12, page P-8. This addendum forms a part of the Contract Documents and, with respect to the Contract Documents, this Addendum shall govern. The effort/cost of work included or excluded by this addendum shall be reflected in the Bidder’s Sealed Bid. A. MODIFICATIONS TO THE FRONT END DOCUMENTS

1. Table of Contents

ADD: To SUPPLEMENTAL INFORMATION the following. “66-inch Pipeline Drawings 84-inch Drawings 120-inch Drawings”

B. MODIFICATIONS TO THE TECHNICAL SPECIFICATIONS

1. Section 02636, “Fiberglass Reinforced Polymer Mortar Pipe” DELETE : In Section 3-7.D the following sentence, “The pit shall not…edge

of the existing pipe.” ADD: In place of deleted the following sentences, “The pit width should

be minimized to avoid conflict with existing utilities and pipelines. The pits may be up to 16 feet wide but under no circumstance encroach within the OC Flood Control Property including shoring material.”

2. Section 02704, “Pipeline Pressure and Leakage Testing” ADD: To end of 1-1. Scope, the following, “The pipeline shall be

pressure tested at 75 psi. In addition to the requirements of this section, if the pipe fails the pressure test it shall be the responsibility for the contractor to identify and repair the leak. The contractor shall prepare a testing plan for review by the Owner.”

3. Section 15062, “Steel Pipe”

ADD: To end of 2-16. PROTECTIVE COATINGS AND LININGS the

following, “In addition to the requirements in this section, exposed exterior coating shall have UV inhibitor.”


C. MODIFICATIONS TO THE PLANS (Note: Sheets not being re-issued for Addendum

unless noted)

1. Drawing No. G-06, Utilities ADD: To end of Note 16 the following, “In addition to the rip rap shown at

grade in the drawings, the contractor shall assume encountering rip rap from 2 feet to 6 feet below grade at the following insertion pit locations. Insertion Pits C, G, H, I, J, and K.”

2. Drawing No. G-06, Construction Notes ADD: The following note, “9. Contractor shall provide a sound barrier

meeting STC-25 requirements. The sound barrier shall be free standing at 20 feet high and 80 feet long and shall meet UBC wind load requirements. The sound barrier should be mobile for potential reuse at other insertion pit locations. Example product is K-rail Mounted Temporary Sound Wall as manufactured by Environmental Noise Control.”

3. Drawing No. C-34, Pipe Detail

DELETE: Notes 1 and 2. ADD: In place of deleted the following: “1. Pipe spacers are recommended

however use of spacers are at the contractor’s discretion based on installation requirements and protection of pipe from damage.”

D. OTHER

1. POTENTIAL BIDDER RFIs A log of RFIs submitted and responded to has been included in Attachment A. Please note that RFI responses which are in bold are responses that have been updated from previous addendum.

2. RE-ISSUED AND NEW DRAWINGS Re-issued drawings have been included in Attachment B.

3. RE-ISSUED AND NEW SPECIFICATIONS None.

Attachment A

Response to Bidders Request for

Information

1 Does all work need to be completed by July 1st, 2021?

No, however as a mimimum the section of pipeline at the north and south ends of the alignment need to be completed by June 30, 2021 per section 01140 as modified by Addendum 2. Pipeline testing would be simplified should the entire pipeline be completed and tested as one section by June 30, 2020. The project must be completed within the 290 calendar days as presented in the Notice Inviting Bids section.

4/14/2020

2 If the 5% DBE goal is met do you still need to submit a GFE package?

Yes - the apparent lowest bidder is required to submit the complete good faith effort documentation summarizing its efforts in the solicitation and hiring process of DBE sub-contractors regardless of the DBE participation percentage. The good faith effort document shall be submitted to OCWD within 48 hours after the bid opening.

4/14/2020

3The bid date is the first day after the Memorial Day Holiday weekend. This will make it difficult to get supplier and subcontractor quotes and forms. The bid date should be moved away from the Holiday.

The bid date will be moved back in Addendum 1. 4/14/2020

4 Does the 30,000LF of slip line experience need to be within the last 5 years? No. 4/14/2020

5 Does the 30,000LF of slip line experience all need to be larger then 48”? Addendum 1 will change to 42-inches and greater. 4/14/2020

6Does this Executive Order affect this OCWD Project? https://www.whitehouse.gov/presidential-actions/executive-order-maximizing-use-american-made-goods-products-materials/

The cited Executive Order pertains to the Buy American Act and this act does not pertain to this project. However the American Iron and Steel provisions do apply to this project. 4/14/2020

7 What work can occur after July 1st, 2021? Any work that is required to complete the project except work within the very north and south areas as defined in section 01140. 4/14/2020

8 ETA for the addendum? By end of day on 4/23/2020 4/14/2020

United Pipeline 1 1

United Pipeline Systems (UPS) has been in business for over 30years and has fused & installed more than 20,000miles of HDPE conventional slipliners and compressed fit liners ranging in size from 2" to 52" in more than 30 countries worldwide. UPS meets the minimum 5 years' experience in sewer rehabilitation and has installed approximately 15,000-lf of 48-in diameter HDPE pipe or larger. Additionally, UPS has also fused & installed roughly 25,000-lf of 42-in diameter and in excess of 100,000-lf of 40-in diameter. Lastly, we will begin work on two 48-in diameter projects later this year. Please verify that United Pipeline Systems is an approved HDPE contractor for this project.

Currently minimum is 48-inch diameter however Addendum 1 will revise to 42-inch. 4/10/2020

Bubalo 1 1 Can a City of Los Angeles SBE certificate (see attached) count as DBE requirements on this project? Yes. This will count as DBE requirement. 4/19/2020

Orange County Water DistrictPlant 2 Secondary Effluent Pipeline Rehabilitation Project

Bid Period RFI Response Log-5/12/20

RFI No. Question#

QUESTIONS DURING ADDENDUM 1 PERIOD

PREBID MEETING QUESTIONS

ReceivedResponseContractor

Page 1 of 7



RFI No. Question# ReceivedResponseContractor

Bubalo 1 2 Regarding the 30,000LF of Pipeline Rehabilitation experience, is this just slip lining work or can Cured In Place Process (CIPP) Pipeline Rehabilitation experience count? No. CIPP will not count towards rehabilitation work. 4/19/2020

Bubalo 1 3Regarding the 30,000LF of Pipeline Rehabilitation experience, what’s the minimum size of slip lining that can be counted towards this 30,000LF of Pipeline Rehabilitation experience?

Currently minimum is 48-inch diameter however Addendum 1 will revise to 42-inch. 4/19/2020

Bubalo 1 4 Regarding the three slip lining project experience, can we include a 42” FRP to Rehabilitate an existing 48” pipe project

Yes. Pipe diameter experience required will be revised from 48-inch to 42-inch in Addendum 1. 4/19/2020

Shea 1 1

Reference is made to Section 02626-1.5 Experience Requirements, which states the following“the installing contractor shall have a minimum of 5 years’ experience in sewer rehabilitation. Experience shall include installation of a minimum of 10,000 linear feet of sewer rehabilitationwith pipe of 48-inch diameter or larger utilizing the same slip lining trenchless technology sewerrehabilitation as is indicated in the bid. Personal experience of the construction manager withother construction companies may be substituted in lieu of the current company experience asapproved by the Engineer and Owner. Additional installation contractor requirements arelocated in the Front-End Documents.” JF Shea has rehabilitated/installed steel liners in over103,960 LF of large diameter welded steel pipelines with diameter ranges from 72” to 120”pipelines. Please consider revising this requirement to include weld steel slip lining experience orexperience slip lining pipelines 48-inch diameter or larger utilizing trenchless technology.

Yes. Welded steel pipe slip lining experience is considered comparable to fiberglass reinforced polymer mortar pipe slip lining installation experience. Section 02636 experience is specifically for the fiberglass reinforced polymer mortar pipe installing contractor. The size requirement of 48-inches is being reduced to 42-inches in Addendum 1.

4/17/2020

Shea 1 2

Reference is made to Section 02637-1.5 Experience Requirements, which states the following“the installing contractor shall have a minimum of 5 years’ experience in sewer rehabilitation. Experience shall include installation of a minimum of 30,000 linear feet of sewer rehabilitationwith pipe of 48-inch diameter or larger utilizing the same slip lining trenchless technology sewerrehabilitation as is indicated in the bid. Personal experience of the construction manager withother construction companies may be substituted in lieu of the current company experience asapproved by the Engineer and Owner. Additional installation contractor requirements arelocated in the Front-End Documents. ” JF Shea has rehabilitated/installed steel liners in over103,960 LF of large diameter welded steel pipelines with diameter ranges from 72” to 120”pipelines. Please consider revising this requirement to include weld steel slip lining experience orexperience slip lining pipelines 48-inch diameter or larger utilizing trenchless technology.

No. Welded steel pipe experience will not be added in this section. Section 02637 experience is specifically for the high density polyethylene pipe installing contractor. It is critical that the installing contractor have large diameter HDPE slip lining experience. The size requirement of 48-inches is being reduced to 42-inches in Addemdum 1.

4/17/2020

Colich 1 1

Will OCWD please provide and Permits allowance bid item with an amount, from which the contractor may be reimbursed the actual permit(s) costs and/or fees? The permit costs and fees are unknown. Providing an allowance amount is fair to both the District and the contractor. Please consider.

An allowance will be added in Addendum 1. 4/21/2020

Colich 1 2

Regarding Special Provision 4.8 J, on PDF page 141 of the Specifications, can OCSD provide more of a specific date(s) and duration(s), or frequency, when their heavy equipment access and maintenance at the EJB will occur (requiring our presence to be prohibited in that area)? This information will aid in planning our work activities in the vicinity of the EFB.

OCSD access for EJB manintenance will occur from the Garfield Ave gate just north of EJB. As such there should be no interference in work between the project and OCSD maintenance activities.

4/21/2020

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Colich 1 3Regarding Special Provision 4.9 K, on PDF page 141 of the Specifications, how many times this latest rainy season (10/15/19 to present) has the P2 Conveyance Pipeline been used as an emergency stormwater conveyance conduit by the OCSD?

From 10/15/2019 to present, the 66-inch was not used for emergency stormwater conveyance. Please note that per the cited specification that in the event the Contractor is asked to return the pipeline to service that the work will be monitiored on a time and materials basis.

4/21/2020

Colich 1 4 Is disinfection of the slip-lined piping required? Reference to statement near the bottom of PDF page 155 (SP 23). No disinfection of the slip-lined pipeline will be required. 4/21/2020

Colich 2 1Will there be a continuous flow of water in the 66” RCP during the duration of the contract? If not, can OCWD or OCSD release a continuous flow to the 66” RCP (say 1 foot deep at least)? Can the released flow be cut off, if needed?

The Bid should be based on the assumption that there will be no flow through the 66" pipeline for the duration of the project particularly once the 66" is cut open for pipe insertion. The contractor awarded the contract may open discussion regarding the possibility of releasing flow for execution of the work however no guarantee is made that release of flow will be allowed.

4/22/2020

Bubalo 2 1

Slip lining FRP pipe and pulling fused HDPE pipe are completely different pipeline rehabilitation technologies and require completely different types of experience. If the winning bidder only has HDPE pipeline (pulling fused pipe) rehabilitation Experience (with little or no Slip Lining FRP experience) but the project goes Slip Lining FRP, will they be awarded the contract with no Slip Lining FRP experience? Please clarify

Per the FRP and HDPE specifications sections and as amended in Addendum 2 qualified personel with specfic experience in FRP and HDPE is required. As such the winning bidder is required to have experienced staff for both the FRP and HDPE work.

4/24/2020

Bubalo 2 2

Slip lining FRP pipe and installing steel liners are completely different pipeline rehabilitation technologies and require completely different types of experience. If the winning bidder only has steel liner install rehabilitation Experience, (with little or no Slip Lining FRP or pulling HDPE pipe experience), will they be awarded the contract with no Slip Lining FRP or pulling HDPE experience? Installing steel liners is not Slip Lining. Please clarify

Same general response as previous question. For example, the General Contractor can have the steel lining experience but when working with the HDPE portions of the project, they must have the qualified staff members for that work per the experience specification section. See Addendum 2.

4/24/2020

Bubalo 2 3 Please clarify if the intent is to go Slip lining FRP pipe or pulling HDPE pipe on this project.

The intent is to receive two bids (Base Bid and Alternative Bid) from each contractor. One bid will be for FRP slipliing (Base Bid) and the other bid for HDPE sliplining (Alternative Bid). Provided all other requirements are met by the contractor, the contractor with the lowest FRP bid will be awarded the contract. After award, the Owner will evaluate and select the sliplining type and award the contract based on the slilling alternative selected.

4/24/2020

Shea 2 1

Reference is made to Contract Drawing No. C-36 “Temporary Connection Details” for the North and South connects, which shows a flex coupling with a short pipe piece with backer rod around the end of the pipe Section. Please provide details on what type of pipe material is required for the end section of pipe. Contract Drawing C-04 and C-19 both show the FRP/HDPE ending before the temporary connections.

Addendum 2 will change the temporary FRP/HDPE section of pipe to steel including the short pipe section which is inserted into the existing 66-inch pipe. 4/23/2020


Page 3 of 7




Shea 2 2

Reference is made to Section 02636-3-4, which states “the existing sewer originally was a 66-inch inside diameter RCP; however, due to corrosion, the interior pipe surfaces has deteriorated and exposed rebar in some locations.” To keep jacking loads to a minimum, the pipe invert section will need to be reasonably smooth when jacking the new pipe. If we encounter rebar and deteriorated surfaces in the lower pipe quadrant it will need to be repaired prior to the installation of the new FRP/HDPE pipe. Currently, we have no way to accurately measure the limits of the necessary repair areas. Please consider adding a Unit Price Bid Item with an estimated quantity to the Contract Bid Schedule.

See the Supplemental Information including RedZone Robotics Laser Scanning Results and Summary of 2012 CCTV Inspection for more detailed information on pipe conditions and locations. In general the location of the deteriorated and exposed rebar areas are NOT within the lower quadrant of the pipe.

4/23/2020

Shea 3 1 On C-39, the valve enclosure is shown as being 1'-6" tall while on S-01 it is detailed as 5'- 0" tall with an 8' clearance. Please clarify. The enclosure shall be 1'-6" tall. See Addendum 2. 4/28/2020

Shea 3 2

On C-39, the valve enclosure is shown as having a 4" flanged base external to the enclosure measurements, while the drawing on S-01 shown this enclosure to have the same outside dimensions as the concrete support structure, which would not allow for a 4" flanged base plate. Please clarify.

The flange will be on the outside as shown on C-39. See Addendum 2. 4/28/2020

Shea 3 3

On C-39, Note 3 indicates the valve enclosure to be constructed of 1/4" thick material minimum. While S-01 depicts the enclosure as being steel framed with an external cladding. Is the Enclosure to be framed with 1/4" Cladding? If so, what metal shape and material is the frame to be manufactured from? If the intent is to have a framed enclosure with cladding, would there still be a need for a flanged skirt, since the frame would be carrying the load? Please provide a clearer detail of the valve enclosure.

The material will be changed to galvanized steel. See Addendum 2. 4/28/2020

Shea 3 4

Insurance Conditions, page IC-2, Item 5. Contractor’s Pollution Liability states in part, ‘optional: if project involves environmental hazards.’ Are there are any environmental hazards involved with this project, thus requiring the Contractor to provide Pollution Liability?

See Addendum 2. 4/28/2020

Shea 3 5

Insurance Conditions, page IC-2, paragraph 1 states, “If the Contractor maintains broader coverage and/or higher limits than the minimums shown above, the OCWD requires and shall be entitled to the broader coverage and/or higher limits maintained by Contractor.” However, current standard insurance policy language only provides limits as required by contract. Please advise if standard insurance language is acceptable.

The language to allow the Agency access to other broader coverage is the new recommended insurance requirements for public entities. 4/28/2020

Shea 4 1

Specification Sections 15102 Plug Valves, 15108 Vacuum Valves and Drawing C-39 note 5, all indicate extra valves and enclosure items are to be procured by the contractor and turned over to the owner. Since these items are not incorporated into the work, please indicated which Bid Item theses materials are to be included in.

Incorporate into Bid Item 6. 4/29/2020

NoCorr Products 1 1

What is the absolute minimum ID pipe that would be required in this project. Currently you have FRPM pipe with 60" and HDPE with 58" ID specified. Metric Pipe size DN1500 mm would offer a 57.5" ID. This is similar to the HDPE pipe that is allowed in this project. We would like to confirm that ASTM D3262 Metric Pipe Series DN1500 with 57.5" ID is allowed matching the HDPE pipe ID in this project.

58" is the minimum ID pipe size. Additional funding for the project was provided by SCE through savings by design based on the diameters included in the specifications and resulting annual pumping energy. A reduction in the ID would increase pumping energy and possibly eliminate funding by SCE.

4/28/2020

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NoCorr Products 1 2

This lining could be done from only two 25' long access pits using FRPM pipe and if intermediate TEEs are required, they could be added after the lining is completed using 10' long access pits, minimizing the time and cost. We would like to confirm that OCWD is respective to cost saving options like this.

OCWD is receptive to cost saving options. Because of the longer duration of work at the two pits, the location f the two pits would need to be evaluated in terms of the impact to local residents.

4/28/2020

NoCorr Products 1 3Is there an incentive for the contractor to complete this project earlier than planned? What is the early completion incentive, if any?

No. 4/28/2020

NoCorr Products 1 4Could the contractors use 38 foot joints lengths on the straight sections and shorter lengths on the curves? Any limitations on the joint lengths as long as the pits are designed for such operations?

There are no limitations on the joint length however the maximum insertion pit length is 100 ft. 4/28/2020

Teichert 1 1

The installing contractor shall have a minimum of 5 years' experience in pipeline rehabilitation. Experience shall include installation of a minimum of 30,000 linear feet of pipeline rehabilitation and three projects with pipe of 42-inch diameter or larger utilizing the same sliplining trenchless technology sewer rehabilitation as is indicated in the bid. Is the 5 years’ specialized experience requirement for both prime contractor and subcontractor?

The minimum of 5 years of experience is required by the actual contractor installing the liner (installing contractor). In the event that the installing contractor is a subcontractor to the prime contractor, the experience requirements refer to the installing contractor. Additional installation contractor requirements are located in the Front End Documents

4/29/2020

Teichert 1 2

Personal experience of the construction manager with other construction companies may be substituted in lieu of the current company experience as approved by the Engineer and Owner. Does the 5 year experience apply to both the prime contractor and personal experience?

Yes. Refer to Addendum 2. The minimum 5 years of experience in pipeline rehabilitation applies to the installing contractor or, with approved by the Engineer and Owner, the personal experience of the onsite field superintendent (either with the installing contractor or with other companies) . In the later case, the personal experience of the onsite field superintendent woudl need to meet the same criteria (length, pipe size and number oif projects) as that set out for the installing contractor.

4/29/2020

Teichert 1 3Prime contractor, Prime’s subcontractor (the installing contactor) , and Personal experience of the construction manager. Does the 5 year experience apply to all of the three parties or just one?

See response to question above. 4/29/2020

Thompson 1 1

Technical Specificati ons Section 1- 2, 2nd Paragraph. “ASTM D3262, Standard Specification for “Fiberglass (Glass-Fiber-Reinforced Thermosetting-Resin) Sewer Pipe.” Revise to “ASTM D3754, Standard Specification for “Fiberglass (Glass-Fiber-Reinforced Thermosetting-Resin) Sewer & Industrial Pressure Pipe.” The industry standard more appropriate for this application is ASTM D3754. Although D3262 is for sewer, it is recommended that D3754, for pressure sewer, be used.

Agree. See Addendum 2. 5/7/2020

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Shea 5 1

1. Plans and Specifications do not provide clarity regarding the backfilling of the pipe at the insertion pits.a)Contract Plans C-34 and C-35 show concrete encasement at the end joints of the pipe. However, there’s no indication the pit shall be concrete encased in its entirety, or only at the end joints. Also, there’s no concrete encasement rebar detail provided and limits of encasement if it’s only encased at the end joints.b)Specifications 02636-3-10.A and 02637-3-12.A states “After the liner material is in place and approved poured in place reinforced concrete arched caps are installed, backfill the access pit excavations as specified in Trenching and Backfilling section and completely restore all disturbed areas as required.” There are no details shown in the plans of cast- in-place reinforced concrete arched cap.c)General Note 15 in G-06 states “Where specifically noted, the pipeline shall be backfilled with slurry to within the top 18” of the surrounding grade.” Plans and specs provide no indication pipe is backfilled with slurry.Please clarify backfilling details of pipe in insertion pits.

a) The intent of the concrete at the end joints is to provide capping/sealing of the RCP pipe ends. Information will be added to identify the extents of this concrete. b) Section will be editted to delete arched cap. Since installation of the flange at the tees will require removal of the entire pipe, the trench will be backfilled per Trenching and Backfilling section. c) Correct. The plans do not at any location where backfill with slurry to 18" is required.

5/12/2020

Buntich 1 1 The outside diameter of HDPE pipe is 63.0” and FRP is set at 62 inch. Could you please confirm and correct the OD to 63 inch for all pipes?

The information provided by the pipe manufacturers during design established the OD for the HDPE as 63.0” and 61.6” for FRP. 5/15/2020

Buntich 1 2 The inside diameter of HDPE pipe is about 57.75”. Would a nominal 57” FRP pipe be acceptable, since they resulting flow capacity would be equal?

No. The two pipe alternatives have been carefully selected to maximize the outside diameter that can be sliplined into the existing pipe, thereby in turn maximizing the finished internal diameter. The inside diameter of the pipeline is designed to provide the maximum available flow capacity to minimize the recurring annual pumping costs.

Buntich 1 3The spacers shown for FRP pipe is not used in long-push slipline operations. The annular space is not enough for any wheeled spacer to be used. We have sliplined over 200,000 LF of FRP pipe without spacers. Please remove spacer requirement for FRP pipes.

The requirement for spacer will be revised to allow the contractor to use them based upon his means and methods. See Addendum 3.

Kiewit 1 1 Are bidders required to submit a price for the HDPE alternate bid item? Yes. 5/12/2020

Kiewit 1 2

Sheets C-31 & C-32 reference detail C on Sheet C-42 for the concrete encasement dimensions for the 60” Steel Pipe. However, Sheets C-34 & C-35 do not reference any details on any encasement for the FRP/HDPE pipe. Please clarify if the contractor is required to encase the FRP/HDPE pipe, and if so please provide dimensions of the encasement.

No concrete encasement is required on the FRP/HDPE Manway tees. Concrete transition "caps" are required as shown on DWG C-34 and C-35. Dimensions and rebar added on C-34 and C-35. See Addendum 3.

5/12/2020

Kiewit 1 3

Spec 02636, Section 3-7.D states, "The pit shall not be wider than required and a no time shall extend more than 2 feet past the outside edge of the existing pipe." Additional space is required to accommodate cutting of host pipe and for the sliplining machine. Please confirm that the pit width is up to the Contractor's means and methods and can be as large as necessary to accommodate the work and fit between the existing pipes on either size. Pits would be up to 16 feet wide.

The pit width should be minimized to avoid conflict with existing utilities and pipelines. The pits may be up to 16 feet wide but at no time shall encroach on OC Flood Control Property. See Addendum 3.

5/12/2020


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Kiewit 1 4

The proximity of the existing 66” RCP-SE line to the existing 120” RCP-SE line at insertion pit E on drawing C-24 and the additional soil load from the slope will possibly require an additional pile on the other side of the 120” RCP-SE line so that pressure from the shoring is not exerted on the existing 120” RCP-SE line. The additional pile would be in close proximity to the existing high pressure digester gas line. If necessary, is it possible to install temporary bracing inside the existing 120” RCP-SE pipe such as timber stulling to avoid installing piles on the East side of the 120” RCP-SE line?

The 120" pipeline is the main active pipeline conveying treated flow from Plant 1 to Plant 2. As such, installation of bracing within the 120" not acceptable. Installation of piles between the 120" and HPDG is permissiable. Coordination with the Owner and a review of the proposed pile locations will be reviewed by the Owner.

5/12/2020

Kiewit 1 5 Can you please provide as-built drawings for the existing 66”, 84”, and 120” RCP-SE lines to verify the wall thickness of these lines? As builts will be provided. 5/12/2020

Kiewit 1 6 Specification 02200B states select material shall be used for backfill. Please confirm the existing soils on-site are suitable for backfill of the insertion pits. The existing on-site soils are suitable for backfill of the insertion pits. 5/12/2020

Kiewit 1 7

Drawing C-34 calls out pipe spacers for the FRP pipe. There is no mention of pipe spacers in the FRP specs and they are not typically used for sliplining FRP pipe. Please clarify if pipe spacers are required for the sliplined FRP pipe. If so, please provide a specification for the pipe spacers.

The requirement for pipe spacers on Drawing C-34 will be revised and the use of spacers will be included as an option. The contractor would submit approach for review and approval. See Addendum 3.

5/12/2020

Kiewit 1 8

During our site walk we noticed a pothole at plant 2 that had been completed which revealed several utilities in close proximity to insertion pit K that appeared to be running parallel over the 66” RCP-SE alignment. Will OCSD relocate all conflicting utilities prior to excavation of the access pits?

No it is the responsibility of the contractor on this project to relocate/support existing utilities for execution of the work. 5/12/2020

Kiewit 1 9

Specification 03610 Low Density Cellular Concrete Grout does not state the required spacing of intermediate grout shafts for grout tubes. Typically, these will need to be spaced about every 150 feet for grouting of the annular space. Is there a maximum distance required for spacing of the intermediate grout shafts?

There is no distance requirement for spacing of grouting tubes. The locations of the grout tubes or how the grout will be installed is part of the contractors means and methods and will be submitted for review and approval during the submittal process.

5/14/2020

Kiewit 1 10

Utilities Note 18 on drawing G-06 states “The Contractor shall assume and include in the bid removal of subsurface rip rap at all insertion pit locations.” Please provide the depth of the existing rip rap that the Contractor should assume needs to be removed at each insertion pit location.

In addition to where rip rap is located on grade, the contractor shall assume rip-rap from 2 to 6 foot below grade at select insertion pits. See Addendum 3. 5/14/2020

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Attachment B

Re-issued and New Drawings

XX

XX

C-23

GROUNDWATER REPLENISHMENT SYSTEM P2 SECONDARY EFFLUENT PIPELINE REHABILITATION

INSERTION PIT DDETAILED PLAN AND SECTION

PRELIMINARY - NOT FOR CONSTRUCTION

1 CONCENCASEMENT

1 5/20 RtB RtB ADDENDUM 3

XX

XX

C-24


INSERTION PIT EDETAILED PLAN AND SECTION


CONCENCASEMENT

1


C-34


FRP TYPICAL DETAILS


2'-0"3'-0"

2'-0

"

(TYP)(TYP)

(TY

P)

#4 @ 6"ALL AROUND

#4 @ 18"ALL AROUND

SEE NOTE 3

3. CONC DIMENSIONS AND REBAR TYPICAL FOR BOTH CLOSURES AT RCP TRANSITIONS.

1

1


C-35


HDPE TYPICAL DETAILS


2'-0"3'-0"

2'-0

"

(TYP)(TYP)

(TY

P)

#4 @ 6"ALL AROUND

#4 @ 18"ALL AROUND

SEE NOTE 3

3. CONC DIMENSIONS AND REBAR TYPICAL FOR BOTH CLOSURES AT RCP TRANSITIONS.

1

1
