Advanced Inspecti on - I

2009—2010

Advanced Design and Inspecti on - I

More informati on is available at our website: htt p://septi c.umn.edu

2Readings & HomeworkBrought to you by. . .

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OSTP Sta can answer ques ons about workshops, U of MN Publica ons, soils, designs, forms, small community issues and technical assistance.

2009-2010 Key Contact Informa on Contact the appropriate organiza on to get your ques ons answered faster!

Minnesota Pollution Control Agency SSTS Contact Information520 Lafayette Road North St. Paul MN 55155 – Email: [email protected] – 651-296-6300 or 800-657-3864

The MPCA can answer ques ons about your business license, professional cer ca on, state rule interpreta on, local ordinance assistance, and business complaints.

Staff person Phone and Email Area of expertise

Clarence Manke St. Paul

[email protected]

Metro Area: Ordinance & Technical Assistance, SSTS Business Complaints, Tank fee, Rule Interpretation

Pat Shelito Brainerd

[email protected]

Central MN and Temporary North East MN: Ordinance & Technical Assistance, SSTS Business Complaints, Rule Interpretation

Brian Green Rochester

[email protected]

South East MN: Ordinance & Technical Assistance, SSTS Business Complaints, Rule Interpretation

Nick Reishus Marshall

[email protected]

South West MN: Ordinance & Technical Assistance, SSTS Business Complaints, Rule Interpretation

Heidi Lindgren Detroit Lakes

[email protected]

North West MN: Ordinance & Technical Assistance, SSTS Business Complaints, Rule Interpretation

Ron Swenson Brainerd

[email protected]

Statewide: Enforcement Supervisor

Mary West St. Paul

[email protected]

Statewide: Program Administration; Technical, Soils and General Ordinance Assistance (backup to regional staff ); Annual Report

Barb McCarthy Duluth

[email protected]

Statewide: SSTS Tank and Product Registration, Soils and Technical Assistance (backup to regional staff )

Mark Wespetal St. Paul

[email protected]

Statewide: Program Administration, Technical Assistance (backup to regional staff )

Gretchen Sabel St. Paul

[email protected]

Statewide: Program Administration, Legislative Issues, General Ordinance Assistance (backup to regional staff ), South West MN Ordinance and Technical Assistance

Bill Priebe St. Paul

[email protected]

Statewide: SSTS Program Policy and Planning Supervisor

Jane Seaver St. Paul

651-757-2201 ext. 2-1; [email protected]: 651-297-8676

Statewide: Individual Certification & Business Licensing

Staff Person Telephone Email Area of expertiseNick Haig 612-625-9797 [email protected] Workshop questions, UMN publications

Jessica Wittwer 612-624-7460 [email protected] Workshops, soils, landscaping

Sara Heger Christopherson

612-625-7243 [email protected] Technical information, design forms

Dave Gustafson 612-625-1774 [email protected] Technical information

Dan Wheeler 612-625-8791 [email protected] Soils, mapping, soil survey

Laurie Brown 218-726-6475 [email protected] Northern MN – Small community, management, or homeowner issues, soils

Doug Malchow 507-280-5575 [email protected] Southern MN – Small community, management, or homeowner issues

University of Minnesota Onsite Sewage Treatment ProgramWater Resources Center • 1985 Buford Avenue, 173 McNeal Hall • St. Paul, MN 55108

(800) 322-8642 • FAX: (612) 624-6434 • Email: sep [email protected] • Web site: h p://sep c.umn.edu

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Subdivision Design steps1. Layout lots2. Set Home sizes or use3. Calculate fl ows from the homes {other use} a. Permit?4. Find elevati ons: a. Right of way b. Homes c. Connecti ons5. Set pipe elevati ons6. Determine pipe length & Size a. Calculate I&I7. Determine fl ow rate per secti on8. Verify pipe velocity9. Gravity a. Find pipe grade b. Check depth i. Limitati ons [Water, Rock…..] ii. > 20’ requires Lift Stati on iii. Determine size iv. Size pumps v. Lift stati on requirements c. Determine manhole locati ons d. Required thrust blocks

10. STEP a. Determine legs i. Find length b. Set N c. Determine Q i. Determine Am d. Calculate Hf e. Calculate Velocity {> 1ft /sec} f. Calculate stati c head g. Pump selecti on Qm : TDH [Hs+Hf] h. Layout : i. Thrust blocks ii. STEP specs iii. Cleanouts iv. Air Release locati ons

11. Pressure sewer a. Determine legs i. Find length b. Set N c. Determine Q i. Determine Qm d. Calculate Hf e. Calculate Velocity {> 1ft /sec} f. Calculate stati c head g. Pump selecti on Qm : TDH [Hs+Hf] h. Layout : i. Thrust blocks ii. STEP specs iii. Cleanouts iv. Air Release locati ons

12. Size Sti lling Tank


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‘At A Glance’ Listing of Proprietary Treatment Products for Typical Residential Strength

Subsurface Sewage Treatment Systems Updated February 4, 2010

Proprietary Products Name and Models

TreatmentLevels

A B C TN

AdvanTex: AX-20 AX20, AX20-2, AX20-3, AX20-4, AX20-5 X X

AdvanTex; AX-20 AX20, AX20-2, AX20-3, AX20-4, AX20-5 with Salcor 3G UV disinfection X X X X

Ecoflo Biofilter; Closed Bottom, STB Models with: Fiberglass shell

• STB-500, STB-500-2, STB-650, STB-650-2, STB-650-3 Concrete shell (gravity discharge)

• STB-650B, STB-650B-2, STB-650B-3 Concrete shell (pump discharge)

• STB-650BR, STB-650BR-2, STB-650BR-3 X X X

Ecopod E50, E60 X

Ecopod E50, E60 with Salcor 3G UV disinfection X X X

Enviro-Guard (non-modular) ENV- 0.75 X

Enviro-Guard (non-modular) ENV-0.750 with Salcor 3G UV disinfection X X X

Enviro-Guard (modular) ENV- 0.75M X

Enviro-Guard (modular) ENV-0.750M with Salcor 3G UV disinfection X X X

FusionZF-450, ZF-600, and ZF-800 X

Hoot H-Series H-500, H-600, H-750, and H-1000 X X

Hoot H-Series H-500, H-600, H-750, and H-1000 with Salcor 3G UV disinfection X X X

MicroFAST0.5, 0.75, 0.9,1.5, 3.0, 4.5, and 9.0 X X

MicroFAST0.5, 0.75, 0.9, and 1.5 with Salcor 3G UV disinfection X X X X

MicroFAST3.0, 4.5, and 9.0 with Norweco chlorine disinfection X X X X

wq-wwists1-21 February 2010 Minnesota Pollution Control Agency • 520 Lafayette Rd. N., St. Paul, MN 55155-4194 • www.pca.state.mn.us

651-296-6300 • 800-657-3864 • TTY 651-282-5332 or 800-657-3864 • Available in alternative formats


Proprietary Products Name and Models

TreatmentLevels

A B C TN

Multi-FloFTB-0.5, FTB-0.6, FTB-0.75, FTB-1.0, and FTB-1.5 X

Multi-FloFTB-0.5, FTB-0.6, FTB-0.75, FTB-1.0, and FTB-1.5 with Salcor 3G UV disinfection X X X

Nayadic M-6A, M-8A, M-1050A, M-1200A, and M-2000A X

Puraflo Peat Fiber Biofilter; Open and Closed Bottom • Open Bottom 1A to 10A • Closed Bottom 1B to 10B X X

RetroFAST0.15, 0.25, and 0.375 X X

RetroFAST0.15, 0.25, and 0.375 with Salcor 3G UV disinfection X X X

‘At A Glance’ Listing of Proprietary Treatment Products for Typical Residential Strength wq-wwists1-21 • February 2010

Page 2 of 2


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MPCA Registered Proprietary Distributi on Media Products, with Bott om Area Equavalance for design purposes

More informati on available at:htt p://www.pca.state.mn.us/programs/ists/productregistrati on.html#media



Onsite Sewage Treatment Program Septic System Management Plan Delta Environmental Products

Ecopod Fixed Film Aerobic Treatment Unit

Ecopod Management Plan 090909

This Management Plan identifies some basic requirements for proper operation and maintenance of the ECOPOD wastewater treatment device for residential use. Refer to the manufacturer’s Operation and Maintenance Manual for ECOPOD wastewater treatment products for detailed instructions on proper system operation and maintenance. Refer to your soil treatment system management plan (below or above-grade) for additional management requirements.

The ECOPOD Manual, submitted by the manufacturer (Delta Environmental Products) as part of the registration of this product in Minnesota, can be found at the Minnesota Pollution Control Agency’s website http://www.pca.state.mn.us/programs/ists/productregistration.html.

SYSTEMCOMPONENT

TASK FREQUENCY RESPONSIBLE PARTY

ECOPODWastewaterTreatmentDevice

Monitor alarm On-going Homeowner Keep vents on blower housing clear of obstruction

On-going Homeowner

Check and clean air filter on the air pump

Every three months Homeowner or Service Provider

Monitor flow Every six months Service Provider Check mechanical and electrical components

Every six months Service Provider

Perform operational field tests on influent/effluent quality including odor, color, turbidity, temperature, dissolved oxygen and pH as appropriate

Every six months Service Provider

Sample effluent as required in the local Operating Permit

See Operating Permit* Service Provider

Check sludge level in all sewage tanks; follow manufacturers recommendations for solids removal

Every six months Service Provider & Maintainer

For seasonal use, follow manufacturers guidelines

As required based on seasonal usage

Service Provider

* Systems designed to meet treatment level A or B with UV disinfection must collect effluent sample for fecal coliform annually at a minimum.

At the time of each service visit, Form 7-2: Aerobic Treatment Unit should be completed. See http://www.onsiteconsortium.org/omspchecklists.html

Items not permitted in the ECOPOD wastewater systems are specified in the ECOPOD Manual for Minnesota.

Sampling requirements may be specified in local operating permits. The protocol for collection of wastewater samples is specified in the ECOPOD Manual for Minnesota.

COLLECTION & TRANSMISSION COMPONENTS

Components Covered: Solids handling sewers

Traditional gravity sewer Pressure sewer with grinder pumps Vacuum sewer

Effluent sewers Septic tank effluent gravity sewer (STEG) Septic tank effluent pump sewer (STEP)

Holding tank

Component purpose: For cluster or small community systems, wastewater must be collected and transmitted to the pretreatment and dispersal components. Thus, the purpose of these components is to collect the wastewater from the building or other facility where the wastewater is generated and to transmit it to the cluster or small community OWTS.

There are several options available, some that handle the total wastewater flow, and others that handle primarily the liquid fraction of the wastewater. Frequently, the options are used in combination to better serve a community.

There are a wide variety of resources available that discuss these collection and transmission components in detail.USEPA has a publication, Manual: Alternative Wastewater Collection Systems, EPA 625/1-91/024, produced in 1991.For this course, just general information will be presented on the options available.

Different Options:

I. Solids handling sewers – collect and transmit all the wastewater, both blackwater and greywater.

A. Traditional gravity sewer – See figure 8.1. Transmits the entire wastewater stream, both liquid and solids. Some older

systems may be combined gravity sewers, conveying both sewage and stormwater.

2. Minimum diameter is 6 to 8 inches. Diameters of big trunk and interceptors are routinely several feet or more in diameter.


Figure 8. Schematic of traditional gravity sewer

ityat an

er than the gravity sewer line, lift or pump stations are

s (manholes) provide access to the collection and

nfiltration. During dry weather times, there may

.

as fats, oils and greases, and solids can cause problems by clogging the pipe.

3. Must maintain a minimum slope so all the wastewater contents flow. Because of this, construction can get quite deep and expensive. Where gravflow is not possible, for example when a house or group of houses is elevation lowconstructed.

4. Periodic access porttransmission lines.

5. Usually there are problems with inflow and infiltration. During wet weather times there are concerns for ibe concerns for exfiltration.

6. Must be designed to maintain minimum velocities so solids don’t get hung up7. Typically requires denser development to justify the high cost for the sewer. 8. Because the entire wastewater stream flows through the pipe, contents such

B. Pressure sewer with grinder pumps – See figure 9.1. Each house or small group of houses has a small pump basin containing a

s the sewage before pumping it into

r pump, they

umps used in some effluent sewers, which are discussed later in this

usually around 30 gallons capacity for a single home grinder pump station.

grinder pump. 2. The grinder pump grinds up or macerate

the collection and transmission sewer. 3. Because the liquid and solids are turned into slurry by the grinde

can be transmitted through small diameter pipe under pressure. 4. Grinder pumps tend to cost more initially and require more maintenance than

effluent psection.

5. The pump basin is typically quite small,


Figure 9. Schematic of typical pressure sewer using grinder pumps

Crites & Tchobanoglous, 1998

6. Because they transmit the entire wastewater flow, the oil and grease content in the wastewater can create problems by plugging the pipes.

7. Because the grinder pumps comminute the sewage into small size particles, the particles can be difficult to remove if traditionally sized septic tanks are the first step in the pretreatment process.

8. The grinder pumps pressurize the collection and transmission mainline. 9. Because a ground up slurry is being transmitted, the collection and

transmission line is smaller diameter (minimum of 2 inches) than a conventional gravity sewer and can follow the topography, either being insulated or installed just below the frost level in cold climate areas.

10. Infiltration and exfiltration should not be problems as the sewer is designed and installed to be watertight.

11. The grinder pumps may be time-dosed to reduce the size of the force main. 12. Solids handling pumps, capable of passing 3-inch solids, have been used in

lieu of grinder pumps, to pump the entire waste stream through small diameter sewers. There may be an increased risk due to solids plugging the lines.

C. Vacuum sewer – See figure 10.1. Sewage from one or more residences or other structures flows by gravity into

a small sump. 2. The sump is connected to a main vacuum line, but is isolated from the vacuum

line by a pneumatic pressure controlled vacuum valve. A negative pressure (typically 15 to 20 inches of mercury) is maintained in the main vacuum line by a central vacuum station.


Figure 10. Schematic of typical vacuum sewer

3. After a predetermined volume of wastewater has entered the sump, the valve opens. The pressure differential between the sump and the main vacuum line results in the wastewater being pulled into the main vacuum line and down to the central vacuum station. Before closing, a quantity of air enters the sump, so the sump does not remain under a vacuum.

4. As the wastewater moves down the main vacuum line, the solids are broken up, resulting in slurry reaching the receiving tank at the central vacuum station. This is enhanced on level or upgrade slopes where the vacuum line has a saw tooth configuration, containing periodic upturns, as noted in figure 10. From there, the wastewater is pumped to the treatment process.

5. Vacuum sewers can flow downhill or uphill. The maximum lift expected is between 15 and 20 feet.

6. As with other alternative collection and transmission components, vacuum sewers are designed and constructed to be watertight. Thus, exfiltration should not be a problem.

7. Historically, this type of collection system has not functioned well continuously. These problems appear to have been resolved in the last decade or so.

II. Effluent sewers – collect and transmit only septic tank effluent. Because they don’t carry solids, they typically have smaller diameters than solids handling sewers.

A. Septic tank effluent gravity (STEG) – See figure 11.1. Each residence or structure or group of structures has a septic tank, which

must be watertight. Each septic tank should have an effluent filter/screen and an access riser.


Figure 11. Schematic of typical STEG sewer

2. Effluent flows from the septic tank via a 1 to 2 inch plastic pipe into a small diameter (typically 2 to 8 inches) gravity flow collection and transmission mainline.

3. Because only septic tank effluent is being carried, the mainline can be placed at somewhat variable grades. This helps minimize the depth of construction.


5. On-going monitoring & maintenance program must include periodic pumping of the septic tanks.

B. Septic tank effluent pump (STEP) – See figure 12.1. Each house or small group of houses has a septic tank, which must be

watertight.2. Each septic tank typically has an effluent pump (frequently it is a high head

pump) to discharge septic tank effluent into a pressurized discharge line (typically 1 to 1 ½ inches diameter) which discharges into the pressure sewer.

3. It is desirable to use an effluent filter/screen in the septic tank to remove more solids prior to pumping into the pressure sewer.

4. The effluent pumps pressurize the collection and transmission mainline. 5. Because it transmits only septic tank effluent, the collection and transmission

line is smaller diameter (minimum of 2 inches) and can follow the topography, either being insulated or installed just below the frost level in cold climate areas.


7. The pumps may be time-dosed to reduce the size of the force main. 8. On-going monitoring & maintenance program must include periodic pumping

of the septic tanks.


Figure 12. Schematic of typical STEP sewer

Crites & Tchobanoglous, 1998


Low Pressure Sewer, as a technology, has been utilized and developed throughout the Unites States over the past 40 years, since its inception in the late 1960’s. The idea of Low Pressure Sewer, stemmed from General Electric engineer’s idea to create a “sewer within a sewer”, brought about the use of individual grinder pumps and small diameter collection lines. Low Pressure Sewer has since been adopted as a means to sewer virtually anywhere; lowering upfront infrastructure costs, maintaining a closed and virtually maintenance free system and promoting the expansion of municipal collection to otherwise non-serviceable areas do to the economics or topography.

The grinder pump, the heart of the Low Pressure Sewer system, services the home or businesses sewer needs, collecting all wastewater and solids. Through the grinding of the waste, “slurry” is discharged through a small, usually 1-1/4” diameter, line into a force main, lift station, manhole or directly to a central treatment system. Transporting sewage several thousand feet to a discharge point at a higher elevation is commonly accomplished with Low Pressure Sewers.


There are many benefits to a Low Pressure Sewer system. Above all is the ability to sewer difficult applications. Areas with undulating terrain, rocky conditions, high groundwater and even the flattest of terrain can benefit from a small diameter collection system, using Low Pressure Sewer. In many of these applications the introduction and acceptance of directional boring, as a means of installation, has furthered the use and acceptance of Low Pressure Sewer.

Directional boring has many advantages over traditional sewer installation. Large, deep trenches are all but eliminated. With less disruption to existing landscaping, roads and driveways, directional boring has the additional benefit of saving time and money. Utility replacement, road closings, detours, expensive dewatering and the restoration costs associated with trenching are substantially reduced.

In conjunction with directional boring is the use of HDPE or high density polyethylene pipe. The primary benefit of HDPE pipe is that the fusion process used in connecting multiple lines creates a closed line. Low Pressure Sewer systems are closed systems. There is no infiltration and inflow. The absence of I & I in a Low Pressure Sewer system has the added benefit of maintaining a constant flow to the discharge or treatment point, eliminating plant overflows.


In environmentally sensitive areas, Low Pressure Sewer systems do not allow for leaching of the system into the surrounding environment. Low Pressure Sewer is a common means of providing municipal sewer collection to lake communities and wetland areas. The small diameter tanks are easily installed to small lake front properties. In fact, the tanks can be dropped into existing septic tanks, further reducing disruption to the surrounding environment.

For the municipality, Low Pressure Sewer has become a popular collection system. Low Pressure Sewer all but eliminates manholes needed in gravity systems. In addition, Low Pressure Sewer can reduce and in many applications eliminate the need for lift stations to transport the sewage to the final destination. Eliminating manholes and dramatically reducing the number of lift station substantially reduces the maintenance costs associated with gravity systems.


Types of Collection

There are two types of collection and pumping systems used in Low Pressure Sewer. A STEP system, or Septic Tank Effluent Pump, pumps effluent to a collection or treatment point. Solids are left in the septic tank to be pumped out frequently by a vacuum truck. Access to the tank is required for pumping. The tank itself offers greater storage capacity, however with its large size a higher installation cost is associated with the system. As with all large holding tanks, there is the potential for corrosion and an odor to accumulate within the tank as the wastewater becomes septic.

The second option is the use of a grinder pump, which grinds and pumps all waste solids from the basin to a collection or treatment point. A grinder pump has a smaller basin than a septic tank and thus less storage, usually 8-12 hours. However, there is a lower installation cost associated with the system. Waste water in the tank is less prone to generate odors and develop corrosive properties because of decreased retention time. Additionally, a grinder pump’s small diameter tank means that location on the property is not limited to access needed to perform frequent pumping by a vacuum truck.


There are two types of grinder pumps available, centrifugal or progressing cavity. Each pump type has its specialized application and special evaluation to the characteristics of the pumps should be considered when making a selection. Pump design, performance, preventative maintenance, serviceability and life cycle costs are all variables for consideration.

The differences in pump design between a centrifugal and progressing cavity pump is perhaps the largest contributing factor to the overall dependency and life cycle cost of a pump in a Low Pressure Sewer system. After all, the pump is the heart of the system. Head capabilities are the primary consideration in pump analysis.

Head capabilities or the Total Dynamic Head are the pressures a pump will pump against in a system. TDH can be calculated by looking at the lineal footage a pump needs to move wastewater and the static rise along that same plain. Incorporated into the calculation is the friction loss within the pipe; every type and diameter of pipe has a different friction loss factor.

System Design Characteristics

Low Pressure Sewer systems are designed and, moreover, pipe is sized off of the systems ability to scour and thus be self cleaning. The minimum requirement of the system is that there is a velocity of 2 feet per second thru the lines. The formula for calculating minimum velocity is based off of a principal that there will be a maximum


daily number of pumps that would operate simultaneously in a larger given number of pumps within a system. The review of the data from the initial Low Pressure Sewer projects has resulted in what is now used as the chart, or break down for figuring what the maximum daily number of simultaneously operating pumps would be in any given system size. Table 3 represents the break down of operating pumps versus total number of pumps in a system.

Given the maximum daily number of grinder pumps that will operate simultaneously, the pipe diameter throughout the system can be sized. The diameter of pipe used throughout a system changes as systems are broken into zones. To size a zone, start at the farthest point in the system, rather the point at which is the furthest lineal footage from the discharge point. At this point, the number of pumps that are accumulated correlate to the break in total number of pumps that establish the maximum daily simultaneous operations. Each time another pump is added to the total number of pumps that correlate to the breaks on Table 3, a zone in created and the pipe diameter may change. See Table 7.


As a system is designed, the pipe size increases toward the discharge point, with the number of accumulated pumps increasing. All the time consideration for the required minimum velocity of 2 feet per second stipulates a minimum diameter pipe size. As the pipe diameter increases, the number of pumps that can be accommodated, as daily flow through the pipe, increases.

There are a few design considerations to make when looking at a Low Pressure Sewer. Air/vacuum valves, air release valves and combination air valves serve to prevent the concentration of air at high points within the system. This is accomplished by exhausting large quantities of air as the system is filled and also by releasing pockets of air as they accumulate while the system is in operation and under pressure. Air/vacuum valves and combination valves also serve to prevent a potentially destructive vacuum from forming (Environment One Corporation).

Air/vacuum valves should be installed at all system high points and significant changes in grade. Combination air valves should be installed at those high points where air pockets can form. Air release valves should be installed at intervals of 2,000 to 2,500 feet on all long horizontal runs that lack a clearly defined high point. (Environment One Corporation).


Air relief valves should be installed at the beginning of each downward leg in the system that exhibits a 30-foot or more drop. Trapped pockets of air in the system not only add static head, but also increase friction losses by reducing the cross sectional area available for flow. Air will accumulate in downhill runs preceded by an uphill run (Environment One Corporation).

Long ascending or descending lines require air vacuum of dual-function valves placed at approximately 2000-foot intervals. Long horizontal runs require dual function valves placed at approximately 2000-foot intervals (Environment One Corporation). Pressure air release valves allow air and/or gas to continuously and automatically be release from a pressurized liquid situation. If air or gas pockets collect at the high points in a pumped system, then those pressurized air pockets can begin to displace usable pipe cross section. As the cross section of the pipe artificially decreases, the pump sees this situation as increased resistance to its ability to force the liquid through the pipe (Environment One Corporation). Air relief valves at high points may be necessary, depending on total system head, flow velocity and the particular profile.

Cleanout and flushing stations should be incorporated into the pipe layout. In general, cleanouts should be installed at the terminal end of each main, every 1,000 to 1,500 feet on straight runs of pipe, and whenever two or more mains come together and feed into another main (Environment One Corporation).

A corporation stop should be placed on the lateral between the main and the grinder pump station. In many parts of the country a check valve is incorporated into the lateral line. The check valve serves as a back flow prevent to the grinder pump station. In essence, this is an essential aspect of a Low Pressure Sewer system design however our

climate in Minnesota does not merit the check valve being placed on the lateral line. Each grinder pump station should come equipped with a check valve in the wet well. The second check valve that, normally would be incorporated on the lateral, should be incorporated in the wet well, in the unit basin. This will provide the redundancy of a second check valve and will ensure that a functioning valve is not buried under frost for 7 months out of the year.


Advanced Designer & Inspecti on Homework Night 1

Certi fi cati on

1. T F Advanced Inspectors are required to complete the Service Provider course and exam.

2. T F Advanced Designer and Advanced Inspectors must complete 24 hours of Con- ti nuing Educati on every three years, with at least 12 hours of local soils.

3. T F Advanced Designers and Advanced Inspectors do not need to complete an Indi- vidual Certi fi cati on Applicati on to become Certi fi ed because they do not need a mentor’s signature.

4. T F Advanced Designers and Advanced Inspectors need to carry a higher amount of SSTS Surety Bond coverage than do Basic Designers and Basic Inspectors.

5. T F Aft er February 4, 2011, only Advanced Designers can design a Type IV system with advanced treatment and an operati ng permit; Only Advanced Inspectors can inspect a Type IV system with advanced treatment and an operati ng permit.

Design Guidance

6. T F The use of the design guidance or design by a professional engineer is required by state law.

7. T F The advance designer scope of work is with Type IV systems from 1 to 10,000 gpd (unless a state permit is needed) and all systems 2,501 to 10,000 gpd (un less a state permit is needed).

8. T F The product registrati on process is only registering advanced treatment devices.

9. T F The only extra environmental requirement for Advanced Designed systems is treatment for pharmaceuti cals and personal care products.

10. T F Since Type IV systems use pretreatment devices setbacks can be reduced.

11. T F Two systems owned by two diff erent homeowners associati ons whose combined fl ow is greater than 10,000 gpd and within ½ mile must get a SDS permit.

12. T F A SSTS serving a duplex is considered a UIC Class V injecti on well.

13. T F Type IV systems cannot take both a size reducti on and a verti cal separati on distance reducti on.

14. T F Type IV systems do not need to measure the fl ow.


15. T F Advanced Designer’s can design non-registered treatment devices.

16. What three things need to be assessed before selecti ng a design: 1) 2) 3)

17. T F All Type IV and systems over 2,500 gpd need an operati ng permit.

18. What is the needed verti cal separati on distance if Treatment Level B effl uent is pressure distributed into a Fine Soil?

19. T F Bill Priebe is the statewide SSTS Program Policy and Planning Supervisor at the MPCA.

20. What is the allowable loading rate for a Type IV system with a 47 MPI perc rate?

21. Name 3 things that provide treatment of fecal organisms: 1)

2)

3)

22. T F Local ordinances can prohibit the use of Type IV systems.

23. A treatment device with an effl uent BOD and TSS concentrati on of 20 mg/L and a fecal organism concentrati on of 5,000 colonies/100 mL is classifi ed as what level of treatment?

Determining Flows

24. T F The fl ow calculated for permit type must not be changed for design of specifi c components (such as the collecti on system)

25. T F You can remove your “thinking cap” when using measured fl ow because you have an exact measured value.

26. What two things benefi t if the fl ow esti mate is conservati ve? 1)

2)


27. T F To use measured fl ow data the peak 90 days of fl ow readings must be taken, along with the capacity or use of the facility.

28. T F Measured fl ow from a similar facility can always be used to design a new facility.

29. T F Flow equalizati on must always be used.

Organics, High Strength Waste, and Class V UIC Wells

30. T F Type IV systems must use registered products.

31. T F Waste strength is the combined value of BOD, TSS and phosphorus.

32. T F The term high strength waste is applied to the infl uent to the fi rst treatment component and the effl uent to the soil dispersal system.

33. T F Fats, Oil and Grease are diffi cult to treat due to their high demand for oxygen and the extended ti me some components need to break down.

34. Name the four types of waste streams that may be encountered when designing a SSTS (hint; domesti c sewage is one): 1)

2)

3)

4)

35. T F A system serving a single family dwelling that uses a room as a beauty salon is considered a UIC injecti on well.

36. T F The federal UIC regulati ons only apply in the Metro counti es.

37. T F UIC wells are not individually permitt ed, but can be enforced upon if in violati on of UIC regulati ons.

38. To be in compliance with the UIC rules what three things need to be met: 1)

2)

3)


39. T F Flow equalizati on may also equalize the waste strength.

40. T F Systems receiving only milk house waste are regulated as a SSTS.

41. T F Floor drains from household garages can be put into a SSTS

Hydraulic and Organic Loading

42. Calculate the hydraulic loading rates for a 25,000 square foot retail clothing store with 8 employees? What wastewater characteristi cs might be higher than typical domesti c?

43. Calculate the esti mated hydraulic and organic loading from a daycare facility that provides meals to to 20 children and 5 staff .

44. The busiest seven-day period of 90 recorded daily fl ows are below. What would be a potenti al system design fl ow and the operati ng volume of the surge tank? What is the expected daily surge volume in the fl ow equalizati on tank?

Day Flow (gallons)Monday 500Tuesday 300Wednesday 800Thursday 2000Friday 1500Saturday 2500Sunday 2200


45. A system with a pump operati ng at 33 gpm has an elapsed ti me meter. The following readings were recorded during the last week. Determine the daily fl ow and average daily fl ow. If the design fl ow is 300 gpd, determine if this system is operati ng properly. How many extra gallons where created each day?

Day Pump Run Time (min)

Day 1 1400Day 2 1410Day 3 1423Day 4 1430Day5 1444Day 6 1455Day 7 1467Day 8 1479


Advanced Design and Inspecti on Homework Night Two

Collecti on Systems

1. How much I/I should be accounted for in a 6 inch diameter gravity collecti on system that is 6,864 feet long?

2. Calculate the velocity in the pipe of a 4 inch diameter PVC pipe with a slope of 0.15 feet/feet. Assume gravity fl ow.

3. What is the horizontal separati on distance between collecti on sewer pipe and a water main?

4. What is the separati on distance between collecti on sewer pipe and a water supply well?

5. How much verti cal separati on must be provided between a collecti on sewer pipe and a water main at crossings?


Septi c Tanks

6. Esti mate the typical wastewater fl ow from a school with a cafeteria, gym with showers, and an expected enrollment of 550 students and 25 employees. What size septi c tank would be required with gravity fl ow? Express answer in gallons.

7. A cluster SSTS serving 9 homes is being planned. 3 homes have 2 bedrooms, 4 homes have 3 bedrooms, and 2 homes have 4 bedrooms. Grinder pumps are located at each home with 1000 feet of 2” collecti on delievering the effl uent to a common treatment system. What is the minimum required common septi c tank capacity?


Dwelling#

# of Bedrooms (minimum = 2)

DwellingClassification(see Table IV)

7080.1860Design Flow (gpd)

(See Table 1)

Reduction Factor- 0.45

(if applicable*)

LISTS Flow perDwelling (gpd)

1

2

3

4

5

6

7

8

9

10

11

12

13

14

OSTP Flow Estimation:

Existing Dwellings

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

* Use 1.0 for the flow from the ten hightest flow dwellings and 0.45 for remaining dwellings

Total Dwelling Flow Estimate


1. Flow from Dwellings Flow from Dwellings gpd

2. Flow from Other Establishments

Permitting Flow from Other Establishments

gpd

a) Total Length of CollectionPipe:

feet

b) Diameter of Pipe (Minimum of 2 in):

inches

c) Flow from I& I in Collection System:

gpd

gpd

OSTP Final Permitting FlowWorksheet

Design flow must include 200 gallons of infiltration and inflow

per inch of collection pipe diameter per mile per day with a minimum pipe diameter of two

inches. Flow values can be further increased if the system employs

treatment devices that will infiltrate precipitation.

4. Final Permitting Flow

From either existing and new development worksheet

From either Measured or Estimated-OE worksheet

Sum of 1, 2 and 3c.

3. Flow from Collection System


8. Will the tank below need additi onal ballast to avoid fl otati on? If so, suggest two opti ons.

Tank characteristi cs: • 1700 gallon septi c tank • weighs 19,000 lbs • Outside dimensions of: i. 12 ft (length) by ii. 6 ft (width) by iii. 5.66 ft (height) • 3-inch thick concrete sides • Buried with ½ ft of sandy soil cover. • Minimum depth of wastewater expected in the tank is 20 inches.

Additi onal useful data: • The tank has a totally full capacity of 2156 gallons {8163 L}. • Ignore the inside baffl es. • Assume that the ground water level will come up to the original grade.

Pump and Pump Tanks

9. The elevati on diff erent from pump to its discharge point is water surface is 10’. Discharge pipe length is 200’ of 2.0” PVC. Specifi ed pump can deliever the required discharge of 40 gpm at up to 15 feet of TDH. Are there any concerns with the Installer replacing the specifi ed 2” with 1.5” PVC pipe?

10. A pump tank with dimensions of 4 feet wide and 6 feet long had the water level drop 8 inches in 6 minutes. Determine the pump delivery rate in gallons per minute.


Distributi on11. Design a non-level pressure distributi on for an at-grade with two laterals: • Line 1 at elevati on 104’ • Length of soil treatment area = 75’ • Line 2 at elevati on 102’ • Length of soil treatment area = 60’

1. Enter soil treatment area (STA) length in order of the Highest Elevation to the Lowest Elevation:

Lateral 1 Pipe Elevation ft ft Highest

Lateral 2 Pipe Elevation ft Length of STA ft



Lateral 5 Pipe Elevation ft Length of STA ft Lowest

2. Calculate Change in Elevation over the laterals

= Highest Elevation (Lateral 1) - Lowest Elevation (Last Lateral above) ft - ft = ft

3. Select Minimum Average Head : ft

Use 1.0 ft for dwellings using 1/4 inch or 3/16 inch holes.

Use 2.0 ft for dwellings using 1/8 inch holes; or, for MSTS or other establishments using 1/4 inch or 3/16 inch holes.

4. Calculate the Total Head = Minimum Average Head (Line 3) + Change in Elevation (Line 2)

ft + ft = ft

5. Calculate Pressure Head for Each Lateral

A. Highest trench elevation (Pipe Elevation 1): Pressure Head equals Minimum Average Head (Line 3)

B. All other trenches: Pressure Head equals Minimum Average Head (Line 3) plus the Change in Elevation from Lateral 1.

OSTP Non-Level Pressure Distribution Design Worksheet

This worksheet cannot be used for a Minimum Average Head of 5.0 feet. Design must be modified or valving must be used to equalize flow.

Minimum Average Head Pressure HeadElevation of

Length of STA from manifold

Elevation of

Lat 1 ft + [ ft - ft] = ft





6. Determine the Flow Rate per Hole

c=0.60; d=perforation diameter; h=pressure head

or Calculate Perforation Discharge (Q) in GPM:

Lat 1 Pressure Head = GPM FALSE HighestFALSE

Lat 2 Pressure Head = GPM FALSEFALSE



Lat 5 Pressure Head = GPM FALSE Lowestft Perforation Diameter

Minimum Average Head Pressure Head

ft Perforation Diameter

Elevation of L t l 1




Select a Perforation Diameter and the corresponding gallonsper minute from Table I, interpolating as needed.

Elevation of L t l

hcdQ 265.19



7. Calculate Flow in Gallons Per Minute for Lateral 1

A. Select Perforation Spacing : feet

B. Length of Laterals = Length of STA (Line 1) - 2 Feet

C.

ft/ ft = Spaces

D. Select Type of Manifold Connection (End or Center):

E. Number of Perforations =Number of Perforation Spaces (Line 11) + 1.

F. Flow Rate for Lateral 1 = Number of Perforations X Flow Rate Per Hole for Lateral 1

X = GPM for Lateral 1

8.

Gallons Per Length = Flow Rate for Lateral 1 divided by Length of Lateral 1

÷ = GPM/Foot

Number of Perforation Spaces = Divide the Length of Lateral 1 (7.B) by the Perforation Spacing (Line 10) and round down to the nearest whole number. Check Table II to ensure the maximum number of perforations is not exceeded.

Calculate the Gallons Per Minute Per Foot for Lateral 1. This value will then be used to make surethat the gallons per minute per foot is equivalent in each lateral

- 2 ft =

Spaces +1 =

End Center

9. Balance flows for other lateral lengths, spacing, and size.

If you end up with large perforation spacing (3' is max) lower the initial spacing for Lateral 1 (Line 7.A) or the perforation size (Line 6)

Lateral 2 GPM = Length of Lateral X Gallons Per Minute Per Foot (Line 8)

ft X GPM

Number of Perforations = GPM/Flow Rate for Lateral 2 (Line 6.2)

÷ = Perforations Select Type of Manifold Connection (End or Center):

Spacing = (Length of Lateral)/(Number of Perforations -1)

( = ft

Check Table to ensure the maximum number of perforations is not exceeded.

) ÷ ( Perforations-1)

GPM/ft=

End Center




ft X GPM




( = ft


ft X GPM




( = ft


ft X GPM




GPM/Ft=

) ÷ (

Perforations-1)



GPM/Ft=

GPM/Ft=

) ÷ (

Perforations-1)

End Center

End Center

End CenterSpacing = (Length of Lateral)/(Number of Perforations -1)

( = ft

10. Calculate Total GPM for system - the total GPM need from the pump.

Lateral 1 Flow + Lateral 2 Flow + Lateral 3 Flow + Lateral 4 Flow + Lateral 5 Flow = Total Flow

+ + + + = GPM

11. Summary

Highest

Lowest

Lateral 4

Min. Delieved Dose Volume = Five X the Total Volume of Piping =

Lateral 5

(Date)(License #)

I hereby certify that I have completed this work in accordance with all applicable ordinances, rules and laws.

(Designer) (Signature)

Lateral 3

Total Volume of Distribution Piping =

Lateral 2

Lateral 1

Enter the minimum pipe size that allows for even distribution and the volume of liquid in the pipe from the table.

Perforations-1)) ÷ (

Total Volume to Fill Pipe

(gal) Spacing (ft)Perforation

Size (in)Pipe Length

(ft)Pipe Volume

(gal/ft)Pipe Size (in)

End Center


Pump Selecti on

12. What is the advantage of pumps in parallel?

13. Why can an Advanced Designer use a pump that delivers 11 gpm for a pressure system with 12 homes in the subdivision?

14. From the diagram, what is the system curve?

15. What is the esti mated operati ng point?


A. 0

1. If pumping to gravity enter the gallon per minute of the pump: GPM

2. If pumping to pressure, is the pump for the treatment system or the collection system:

0

3. If pumping to a pressurized treatment system, what part or type of system:

4. If pumping to a pressurized distribution system: GPM

(Line 11 of Pressure Distribution or Line 10 of Non-Level or enter if Collection System)

3. ft

4. ft

5.

1. PUMP CAPACITY

Elevation Difference

Additional Head Loss:

Distribution Head Loss:

OSTP Pump Selection Design Worksheet

2. HEAD REQUIREMENTS

NOTE : IF system is an individual subsurface sewage treatment system, complete steps 4 - 9. If system is a Collection System, skip steps 4, 5, 7 and 8 and go to Step 10.

ft (due to special equipment, etc.)

between pump and point of discharge:

Pumping to Gravity or Pressure Distribution:

Soil Treatment Unit Media Filter Other

Collection System

Gravity Pressure

Treatment System

6. A. Supply Pipe Diameter: in

B. Supply Pipe Length: ft

7.

Friction Loss =

8.

ft X 1.25 = ft

9.

ft per 100ft X ft ÷ 100 = ft

Based on Friction Loss in Plastic Pipe per 100ft from Table I:

Calculate Supply Friction Loss by multiplying Friction Loss Per 100ft (Line 6) by the Equivalent Pipe Length (Line 7) and divide by 100.

Determine Equivalent Pipe Length from pump discharge to soil dispersal area discharge point. Estimate by adding 25% to supply pipe length for fitting loss. Supply Pipe Length (5.B) X 1.25 = Equivalent Pipe Length

Supply Friction Loss =

ft per 100ft of pipe

Soil Treatment Unit Media Filter Other

Collection System

Gravity Pressure

Treatment System


OSTP Pump Selection Design Worksheet

10. Equivalent length of pipe fittings.

Quantity X Equivalent Length Factor = Equivalent Length

X =

X =

X =

X =

X =

X =

X =

X =

X =

X =

X =

A. Sum of Equivalent Length due to pipe fittings: ft

B. Total Pipe Length = Supply Pipe Length (5.B) + Equivalent Pipe Length (9.A.)

Hazen-Williams Equation for h

Valve 11

NOTE: System installer should contact system designer if the number of fittings varies from the design to the actual installation.

Section 10 is for Collection Systems ONLY and does NOT need to be completed for individual subsurface sewage treatment systems.

QuantityFitting Type

45 Deg Elbow

90 Deg Elbow

Gate Valve

Equivalent Length Factor

Equivalent Length (ft)

Butterfly Valve

Globe Valve

Angle Valve

Tee - Branch Flow

Tee - Flow Thru

Swing Check Valve

Valve 10

NOTE: Equivalent length values for PVC pipe fittings are based on calculations using the Hazen-Williams Equation. See Advanced Designs for SSTS for equation. Other pipe material may require different equivalent length factors. Verify other equivalent length factors with pipe material manufacturer.

LCQh *)(*5.10 85.1ft + ft = ft

C. Hazen-Williams friction loss due to pipe fittings and supply pipe (hf): Q in gpm L in feet D in inches C = 130

X ( X Total Pipe Length (10.B)

in4.87 ) X ( gpm ÷ 130)1.85 X ft = ft

11.

ft + ft + ft + ft = ft

Total Head requirement is the sum of the Elevation Difference (Line 3), the Distribution Head Loss (Line 4), Additional Head Loss (Line 5), and either Supply Friction Loss (Line 9 ), or Friction Loss from the Supply Pipe and Pipe Fittings for collection systems (Line 10.C)

Pipe Diameter4.87 )

(10.5 ÷

I hereby certify that I have completed this work in accordance with all applicable ordinances, rules and laws.

GPM (Line 1 or Line 2) with at least feet of total head.

(10.5 ÷ Flow Rate ÷ Constant)1.85

Pump typeComments:

3. PUMP SELECTION

(Date)

NOTE: Friction Loss from the Supply Pipe and Pipe Fittings (Line 9.C) need ONLY be used if system is a collection system.

(Designer) (Signature) (License #)

NOTE: Supply Friction Loss (Line 8) need ONLY be used if NOT a collection system.

A pump must be selected to deliver at least

LCQD

hf *)(* 85.187.4


Documents

Advanced Inspecti on - I