MOUNT PLEASANT WATERWORKS

WASTEWATER COLLECTION SYSTEM SPECIFICATIONS

2004 Edition

Approved by SCDHECl June 1, 2004

PREFACE In an attempt to standardize the wastewater collection systems being deeded to or constructed for Mount Pleasant Waterworks (MPW), we have developed the following specifications for items that shall be incorporated into the design and construction of all wastewater collection systems. These specifications should be followed. If they must be deviated from, you should contact MPW’s Engineering Department at (843) 849-2745, and discuss the reasons for the deviation. We are aware that not all items will work in all situations and must ask for your cooperation in working with MPW to resolve problem areas. If you have any comments concerning these specifications, please feel free to contact us. These specifications will be updated periodically as deemed necessary. Contact MPW to verify that the revision you are working with is the most recent. All standards cited in the text refer to the latest revision of that standard under the same specification number or to superseding specifications under a new number. Please refer to MPW's "Guidelines for Development" for a detailed explanation of procedures and requirements that a developer must follow in order to plan, construct, and have MPW accept a wastewater extension for operation and maintenance.

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CHAPTER 1 WASTEWATER SYSTEM DESIGN STANDARDS

Topics covered in this chapter include:

! Protection of water supplies ! Service laterals and wyes ! General considerations ! Grease traps

Design standards as a minimum, shall conform to the requirements of SCDHEC and the latest Edition of the Ten State Standards. SECTION 1.1 - PROTECTION OF WATER SUPPLIES 1.1.1 Water Supply Interconnection: There shall be no physical connections between a public or private

potable water supply system and a wastewater system, or appurtenance thereto which would permit the passage of any wastewater or polluted water into the potable supply. No water pipe shall pass through or come in contact with any part of a gravity wastewater line or manhole.

1.1.2 Relation to Waterworks Structures: While no general statement can be made to cover all conditions, it

is generally recognized that wastewater shall meet the requirements of the appropriate reviewing agency with respect to minimum distances from public water supply wells or other water supply sources and structures.

1.1.3 Relation to Water Mains: 1. Horizontal Separation: Wastewater lines shall be laid at least ten (10') feet horizontally from any

existing or proposed water main. The distance shall be measured edge to edge. In cases where it is not practical to maintain a ten foot separation, the appropriate reviewing agency may allow deviation on a case-by-case basis, if supported by data from the design engineer. Such deviation may allow installation of the wastewater line closer to a water main, provided that the water main is in a separate trench or on an undisturbed earth shelf located on one side of the wastewater line and at an elevation so the bottom of the water main is at least eighteen (18”) inches above the top of the wastewater line. The above requirements apply to either gravity wastewater or force mains.

2. Crossing: Wastewater lines crossing water mains shall be laid to provide a minimum vertical distance of

eighteen (18") inches between the outside of the water main and the outside of the wastewater line. This shall be the case where the water main is either above or below the wastewater line. The above requirements apply to all gravity wastewater mains or service laterals and force mains.

The crossing shall be arranged so that the wastewater line joints shall be equidistant and as far as possible from the water main joints. Where a water main crosses under a wastewater line, adequate structural support shall be provided for the wastewater line to prevent damage to the water main.

3. Special Conditions: When it is impossible to obtain proper horizontal and vertical separation as

stipulated above, the wastewater line shall be designed and constructed as follows:

a. Maximize the distances between the wastewater lines and the potable water mains and the joints of each;

b. The pipe materials shall be equal to water pipe and shall be pressure tested to assure water

tightness prior to backfilling;

c. Allow enough distance to make repairs to one of the lines without damaging the other.

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SECTION 1.2 - SERVICE LATERALS AND WYES Service Laterals: 1. Service laterals shall be installed where required to provide a connection from the gravity wastewater line to

all lots. Wastewater service laterals shall terminate at the property line, unless otherwise directed. (See Construction Detail No. 1 & No. 2). Service lines to houses shall be four (4") inch schedule 40 minimums. If less than eighteen (18") inches of cover is provided underneath driveways or storm drains, or if less than thirty-six (36") inches of cover is provided underneath drainage ditches or swales, service lines shall be poly-lined ductile iron pipe (DIP). Transition from PVC to DIP shall be made with gasketed, PVC slip-on transition couplings. Fernco or MJ couplings are not approved. (See Construction Detail No. 3). See Appendix "1" for MPW requirements and procedures for connecting buildings to service laterals.

2. Service laterals from the main to the property line shall consist of 6" diameter DIP or PVC and conform to the

requirements of these specifications. A service wye shall be installed at the end of each service lateral and plugged in a manner to allow for air testing. The depth of a service shall be a minimum of thirty-six (36") inches below finished grade, and a maximum of sixty (60") inches. Service laterals must be provided with cleanouts spaced not more than seventy-five (75') feet apart. Vertical stacks shall be provided for service connections and shall be terminated with a cleanout, installed at finish grade level, and fitted with a concrete collar, which incorporates a cast-iron cap. The concrete collar shall be set at the proper grade so that the cast iron cap does not rest on the threaded PVC cleanout cap (See Construction Detail No. 1, No. 2, No. 3, No. 4 & No. 5).

3. Service laterals shall be connected at manholes whenever possible and installed so the crown of main

wastewater lines and service laterals are the same elevations. Where services enter manholes at a height of two (2') feet or more above the main line, an inside drop (See Construction Detail 6) shall be brought down to the bench.

1.2.2 WYES: 1. Wye branches shall be installed in gravity wastewater lines as required. If such branches are not used

immediately they shall be capped as specified by the manufacturer. 2. If the work consists of the construction of a wastewater line that is to replace an existing wastewater line,

all of the existing service lines shall be connected to the new line by a method approved by MPW prior to construction.

3. Wyes shall be installed in gravity wastewater line so as to properly serve each existing house and each

vacant lot facing or abutting the street or alley in which the wastewater line is being laid, and at such other locations as may be designated by MPW. The Engineer, before backfilling, shall determine the exact location of each connection.

4. Wyes shall be of the same material and strength as the main line on which they are installed. 1.2.3 Marking and Protecting Wyes and Service Laterals: 1. Location of wyes and ends of service laterals shall be shown on As-Built Drawings. 2. The location of the ends of all wyes and service laterals shall be marked and protected. All service lateral

stacks shall be protected from damage by the installation of three (3) metal fence posts arranged in a triangular pattern around the service cleanout stack and encircled with orange protective mesh a minimum of three (3') feet in height (See Construction Detail No. 7). Service wyes shall have plugs and stacks secured so as to withstand low-pressure air test (max. 9.0 psig).

3. In developments where concrete curb is installed, the location of all wastewater service laterals shall be

marked on the curb. Using a pipe saw or other suitable tool, a small “S” shall be ground into the curb adjacent to the wastewater service

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SECTION 1.3 - GENERAL CONSIDERATIONS 1. All connections to existing MPW manholes or collection systems must be made in the presence of an

MPW Inspector. All new holes in existing manholes shall be core drilled. A rubber gasket and/or link seal shall be used to seal core hole.

2. All single family or multi-family units must be served with an MPW acceptable sanitary wastewater

collection system. No more than two single family or multi-family units may be connected to one six (6") inch lateral service. Six (6") inch or four (4") inch collection systems will not be allowed, unless specifically approved by MPW and SCDHEC.

3. All sanitary wastewater lines shall be installed outside of pavement area when possible and within the

road right-of-way. 4. No wastewater line of any type shall be allowed to pass through any storm drainage structure without

prior approval of MPW. 5. Casing pipes shall be installed at:

a) Highway crossings, as directed by SCDOT, or;

b) As designated by MPW. 6. MPW will only consider for operation and maintenance, wastewater systems installed:

a) Within the boundaries of the MPW service area.

b) Systems meeting the requirements of these specifications and installed in a manner acceptable to MPW.

7. No system shall be put into service until MPW issues a letter of willingness to operate and maintain the

system, and SCDHEC permits the system for operation. 8. It is the contracting plumber's responsibility to check the As-Built Drawings and physically locate the service

lateral (See Appendix “B”, Wastewater Service Lateral Location Policy). SECTION 1.4 - GREASE TRAPS (SEE MPW OIL, GREASE AND SOLIDS REMOVAL STANDARD, APPENDIX “C”) 1. All facilities dealing with food preparation, automotive/mechanical repairs, or any operation involving

grease by products shall install adequately sized grease traps to remove grease from the wastewater stream prior to treatment. A separate line from kitchen facilities shall be run to grease traps.

Plumbing plans must be submitted to MPW for approval before construction begins. MPW will not provide service to the facility until the grease trap has passed inspection. Wastewater from garbage grinders should not be discharged to grease traps.

2. Flow control fittings should be installed on the inlet side of traps to protect against overloading or sudden

surges. Grease traps shall be sized in accordance with Section 3.2 of MPW’s Oil, Grease and Solids Removal Standard (See Appendix “C”).

NOTE: Minimum size grease trap shall be 1000 gallons.

3. Under certain circumstances MPW may approve internal grease traps (such as the Zurn Models.) Refer to MPW's Oil, Grease and Solids Removal Standard for further information.

4. It is the responsibility of the owner to assure grease traps are operated and cleaned regularly to

prevent the escape of appreciable quantities of grease.

5. In the event MPW wastewater lines become blocked with grease due to an improperly maintained or faulty grease trap, MPW shall recover all costs incurred for corrective measures from the owner.

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CHAPTER 2 SAFETY

Topics covered in this chapter include:

! Responsibilities ! Accident Prevention

SECTION 2.1 - RESPONSIBILITIES The Contractor is responsible for assuring that construction safety procedures, as required by Federal, State, and Local Regulations, are observed. The Contractor is required to take all necessary steps to prevent injury to persons or property in the performance of his contract. If the MPW Inspector, as part of his routine duties, observes unsafe practices or construction methods, he will normally inform the Contractor's Superintendent or Developer's Engineer of the hazard. If appropriate action is not taken, MPW’s Inspector may direct that all work be stopped until corrective measures are taken to assure a safe working environment. The Contractor will remedy all damage, injury or loss to any property caused, directly or indirectly, in whole or in part by the Contractor, Subcontractor, anyone directly or indirectly employed by either of them, or anyone for whose acts any of them may be liable. SECTION 2.2 - ACCIDENT PREVENTION In the performance of the contract, the Contractor shall comply with the applicable provisions of the regulations issued by the Secretary of Labor pursuant to Section 107 of the Contract Work Hours and Safety Standards Act Entitled "Safety and Health Regulations for Construction" C29 CFT 1518, renumbered as Part 1926. Occupational Safety and Health Standards (29 CFR Part 1910) issued by the Secretary of Labor pursuant to the Williams Steigen Occupational Safety and Health Act of 1970 are applicable to work performed by the Contractor subject to the provisions of the act. The Contractor will utilize and maintain, as required by conditions and progress of the work, all necessary safeguards. He will notify owners of adjacent utilities or property, when execution of the work may affect them. The Contractor will take all necessary precautions for the safety of the general public as well as his employees. All roadside work shall be properly marked, with lights, cones, and barrels in accordance with the most recent Revision of “Part V of the South Carolina Manual on Uniform Traffic Control Devices for Streets and Highways.” At all times during the construction of the project and its component parts, the Contractor shall provide, install, and maintain proper temporary supports, shoring, and bracing to prevent any damage, injury, or loss to all employees performing the work and other persons who may be affected.

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CHAPTER 3 TRENCH EXCAVATION AND BACKFILL

Topics covered in this chapter include:

! Backfill materials ! Execution

SECTION 3.1 - BACKFILL MATERIALS 3.1.1 Class I (Concrete) Backfill: 1. Conform to ASTM C 94, Alternate 3. Proportion to obtain a 28-day compressive strength of 3,000 pounds

per square inch. Use a minimum of five bags of cement per cubic yard of concrete. 2. Use Class I (concrete) backfill where there is less than twenty-four (24") inches of cover over the pipe for

proper protection. Class I is also required when a water main and a wastewater line cross with less than eighteen (18") inches clearance. In this case, the wastewater line shall be ductile iron pipe, which may be required to be encased in concrete.

3.1.2 Class II Backfill: 1. Material suitable for Class II backfill in a properly dewatered trench shall consist of any of the following:

well-graded coarse granular materials free of roots, branches, stumps, or other material not so suited, with maximum particle size not exceeding one (1") inch; sands, silty-sands or clayey-sands. Soils having more than twenty-five (25%) percent of its weight passing a No. 200 sieve shall not be used for backfill.

2. Class II Backfill shall be limited to paved streets, driveways and parking lots where final surface

replacement will be made shortly after backfilling and subsequent settlement must be held to a minimum. 3. Class II backfill shall also be used under all culverts, water, gas, irrigation, and wastewater lines, buried

telephone, power and television cables, and any other buried pipelines or cables that cross the excavated trench.

3.1.3 Class III Backfill: Class III backfill shall be used throughout the project and will generally be excavated

trench material free of roots, branches, stumps, or other unsuitable material. It is intended that all surfaces for which Class III backfill is specified shall be returned to equal or better condition than existed prior to construction. Surfaces shall not settle or rut due to normal weathering or vehicular traffic that can be expected for each area.

3.1.4 Imported Backfill Class: If the soils encountered in the trench are not suitable for backfill as outlined

above, the Contractor shall import suitable backfill material for use in the trench. The backfill material shall conform to Class II requirements as a minimum.

SECTION 3.2 - EXECUTION 3.2.1 Preparation of Right-of-way: 1. Obstructions: Remove obstructions within the trench area or adjacent thereto such as, but not limited

to, tree roots, stumps, abandoned pilings, buildings, concrete structures, logs, and debris of all types. Properly dispose of obstructions removed from the excavation in accordance with local municipality requirements.

2. Pavement, Curb, and Sidewalk Removal: Cut all bituminous and concrete pavements, regardless of

thickness, and all curbs and sidewalks, prior to excavation of the trenches as specified in the South Carolina Department of Transportation Policy. Width of the pavement cut shall be twelve (12") inches greater on each side of the required width of the trench at ground surface (See Construction Detail No. 8). Cut lines shall be even and parallel. Pavement and concrete materials removed shall be hauled from the site and not used for trench backfill.

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3.2.2 Excavation: 1. Trench Width: Minimum width of unsheeted trenches in which pipe is to be laid shall be eighteen (18")

inches greater than the inside diameter of the pipe, but not less than that required for proper compaction around the pipe. Sheeting requirements shall be independent of trench widths. The maximum trench width at the top of the pipe zone is limited to 1.33 times the pipe outside diameter plus eighteen (18") inches. In general, the maximum width at the top of the trench will not be limited, except where excess width of excavation would cause damage to adjacent structures or property. However, confine trench widths to dedicated rights-of-way or construction easements, unless special prior written agreements have been made with the affected property owner.

2. Grade: Excavate the trench to the lines and grades shown on the plans with proper allowance for pipe

thickness and for pipe bedding. If the trench is over excavated below the required grade, correct any part of the trench excavated below the grade with crushed stone or Class II backfill as specified herein. Place the bedding over the full width of trench in compacted layers not exceeding six (6") inches deep to the established grade.

3. Shoring, Sheeting, and Bracing of Trenches: Sheet and brace the trench consistent with OSHA

Regulations when necessary to prevent cave-ins during excavation or to protect adjacent structures, property, workmen, and the public. Increase trench widths accordingly by the thickness of the sheeting. Maintain sheeting in place until the pipe has been placed and backfilled. Shoring and sheeting shall be removed, as the backfilling is done, in a manner that will not damage the pipe or permit voids in the backfill. All sheeting, shoring, and bracing of trenches shall conform to the safety requirements of the Federal, State, or Local public agency having jurisdiction. The most stringent of these requirements shall apply.

4. Dewatering: Provide and operate equipment adequate to keep all excavations and trenches free of

water. Remove all water during periods when concrete is being placed, when pipe is being laid, during tunneling or jack and bore operations, during the placing of backfill, and at such other times as required for efficient and safe execution of the work. Prevent settlement or damage to adjacent property. Dispose of water in a manner that will not damage adjacent property. When dewatering open excavations, dewater from outside the structural limits and from a point below the bottom of the excavation. Design dewatering system to prevent removal of soils from the work area.

5. Foundation Stabilization: When the existing material in the bottom of the trench is unsuitable for

supporting the pipe, provide foundation stabilization as follows: Excavate below the pipe zone and backfill to specified grade with 67 granite stone or Class II backfill. Place the crushed stone or Class II backfill over the full width of the trench and compact to the required grade.

3.2.3 Backfill Procedures: 1. Pipe Base and Pipe Zone Backfill: Pipe base shall be crushed stone and gravel conforming to ASTM

C33, Gradation 67 (3/4" to No. 4). Material shall be granite in accordance with SCDOT Specification 406.08. The entire pipe zone shall be compacted to 95% of standard proctor density in accordance with ASTM D698.

2. Trench Backfill Above Pipe Zone - General: When backfill is placed mechanically, push the backfill

material onto the slope of the backfill previously placed and allow to slide down into the trench. Do not push backfill into the trench in such a way as to permit free fall of the material until at least two (2') feet of cover is provided over the top of the pipe. Under no circumstances allow sharp, heavy pieces of material to drop directly onto the pipe. Do not use backfill material of consolidated masses larger than 0.5 cubic foot.

3. Class I (Concrete) Backfill: Place concrete backfill in such a manner that no dirt or foreign material

becomes mixed with the concrete. Minimum thickness of concrete protection shall be six (6") inches on the top and sides of the pipe. Concrete shall have sufficient time to reach initial set before any additional backfill material is placed in the trench. Place stabilized aggregate base in all trenches requiring concrete backfill.

4. Class II Backfill Under Structures, Utilities, and/or Pavement: Backfill the trench above the pipe zone

with approved backfill material in lifts not exceeding six (6") inches loose depth and compact each lift 95%

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of standard proctor density in accordance with ASTM D698, with mechanical vibrating or impact tampers. No mechanical vibrating or impact tampers should be used in the first 24" of lifts above PVC pipe. Maintain the surface of the backfilled trench level with the existing grade using an eight (8") inch layer of stabilized aggregate base until the pavement is replaced. Any trenches, which resulted from, an open cut of State roads, shall be backfilled with flowable grout in accordance with requirements set forth by the SCDOT (See Construction Detail No. 8). Any subsequent settlement of the finished surfacing during the two (2) year warranty period shall be considered to be a result of improper or insufficient compaction and shall be promptly repaired at no cost to MPW.

5. Class III Backfill: Backfill the trench above the pipe zone with excavated trench materials. Place the

backfill in suitable lifts. Determine the type of compaction equipment, and method to provide all of the following: compaction to a density equal to the existing trench side materials but no less than ninety (90%) percent of maximum density as determined by ASTM D 1557; compaction so that subsequent settlement shall be prevented; compaction of graded surface along roads, road shoulders, and other areas subject to vehicular traffic so that the upper 6 inches of backfill reaches a minimum of ninety-five (95%) percent of maximum density as determined by ASTM D 1557.

Remove all boulders and stones 2-inches in diameter and larger from material used for backfill in the upper 12-inches of Class III backfilled trenches. Maintain the surface of the backfilled trench level with the existing grade until the entire project is accepted. Any subsequent settlement of the finished surface during the warranty period shall be considered the result of improper or insufficient compaction and shall be promptly repaired at no cost to MPW.

6. Moisture Control - Backfill: During all compacting operations, maintain optimum practicable moisture

content required for compaction purposes in each lift of the earth fill. Maintain moisture content uniform throughout the lift. Insofar as practicable, add water to the material at the site of excavation. Supplement, if required, by sprinkling the earth fill. During all compaction, the water content of the material shall be at optimum moisture content, plus or minus two (2%) percentage points.

Do not attempt to compact fill material that contains excessive moisture. Aerate material by blading, disking, harrowing, or other methods, to hasten the drying process.

7. Maintenance of Trench Backfill: Maintain the backfilled trench surface until the following activities have

been completed and approved by MPW:

a. Installation of valves and valve boxes. b. Hydrostatic testing. c. Cleanup and restoration of all physical features, utilities restored to their original condition or

better, and, in general, all work required with the exception of repaving.

This maintenance shall include, but not be limited to, the addition of crushed rock backfill material to keep the existing surface and backfilled trenches reasonably smooth, free from ruts and potholes, and suitable for normal traffic flow. No pavement replacement shall be undertaken until all items outlined above have been completed and approved by the agency having jurisdiction.

3.2.4 Compaction Equipment: 1. Utilize compaction equipment of suitable type and adequate to obtain a compaction in accordance with

ASTM D-1557. Operate in strict accordance with the manufacturer’s instructions and recommendations and maintain in such condition that it will deliver the manufacturer's rated compaction.

Impact type compactors are suitable. Rubber tired rollers and track type equipment is not suitable and is not allowed for Class II or III backfill. No mechanical vibrating or impact tampers should be used in first twenty-four (24") inches of lifts above PVC pipe.

2. Compaction: MPW reserves the right to require the contractor to provide, at his expense, all testing

necessary to determine the in-place density and moisture content of the subgrade and compacted fill according to ASTM D-1557.

Test results and a certified statement by the soil testing company that the actual soil compaction found meets these specifications shall be submitted to MPW as soon as they are available to the Contractor.

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3.2.5 Settlement: Any settlement noted within the warranty period in backfill, or in structures built over the

backfill will be considered to be caused by improper construction methods and shall be corrected at no cost to MPW. Structures or paved surfaces damaged by settlement shall be restored to their original condition at no cost to MPW.

3.2.6 Site Cleanliness: During execution of work, conduct cleaning and disposal operations in accordance

with local ordinances and anti-pollution laws. Do not burn or bury rubbish and waste materials on project site. The contractor is also responsible for dust and noise control. MPW’s Inspector may deny final inspection of project until site is cleaned satisfactorily.

3.2.7 Right-of-way Restoration: The contractor shall remove all dirt and debris, thoroughly rake, and clean all

right-of-ways. All right-of-way restoration work shall be in accordance with governing agency permits (i.e., SCDOT, Town of Mount Pleasant, Charleston County). Drainage ditches shall be restored to a SCDOT typical section.

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CHAPTER 4 PIPING AND VALVES

Topics covered in this section include:

! Materials ! Execution ! Testing

SECTION 4.1 - MATERIALS 4.1.1 Pipe Size and Type Selections: 1. On depths of one to three (1'-3') feet use DIP with an approved corrosion-proof interior coating and

external poly-wrap for gravity wastewater lines. 2. On depths of three to sixteen (3'-16') feet use PVC SDR-26 for gravity wastewater lines. (See

Construction Detail No. 9) 3. On depths of sixteen (16') feet and greater use DIP with an approved corrosion-proof interior coating and

external poly-wrap for gravity wastewater lines. 4. Any pipe greater than twelve (12") inches in diameter shall be submitted to MPW for approval prior to

installation regardless of depth. 5. Pipe enclosed in casings shall be DIP with an approved corrosion-proof interior coating only. 6. When a transition is required from a PVC gravity wastewater main or lateral to DIP, mechanical joints or

approved PVC-DIP adapters will be used. No Fernco Couplings will be allowed. 4.1.2 Pipe Material Specifications: 1. Ductile iron pipe and fittings shall be no less than pressure Class 150 and thickness Class 50 meeting the

requirements of ASTM A-377, ANSI A21.50 (AWWA C150) and of ANSI A21.51 (AWWA C151) with a standard outside coating of coal tar or asphalt base material. Interior coating for ductile iron pipe and fittings used shall be 40 mil dry film thickness of Protecto 401 Ceramic Epoxy, Permite Permox 9043 Type II, an equivalent polyethylene lining, or equal. Pipe shall have push-on-joints, mechanical joints (Megalugs), flanged joints, or restrained joints as required. Pipe joints including gaskets shall meet the requirements of ANSI A21.11 (AWWA C111). Fittings shall meet the requirements of ANSI A21.10 (AWWA C110) or ANSI A21.53 (AWWA C153).

2. PVC pressure wastewater piping and PVC fittings shall conform to all requirements of ASTM

Specifications D1784, ASTM D2241, and AWWA Standard C900 or C905 for Class 150 pipe. It shall have a Standard Dimension Ratio (SDR) of not more than 18. All PVC pressure pipe shall be Type 1, Grade 1 PVC suitable for a 150-psi working pressure (minimum) and designed to withstand (without failure) an internal hydrostatic pressure of 500 psi for 1000 hours per ASTM 1598. Joints shall be either push-on type or thermal fusion. Push-on joints shall utilize synthetic rubber ring gaskets conforming to ASTM D1869 and vegetable origin lubricant that is non-toxic and water-soluble. Thermally fused joints shall comply in all respects with the procedures and standards of the pipe manufacturer.

DIP pipe fittings to be used with PVC pipe shall have a corrosion-proof lining as noted in Section 4.1.2, (1). No. 1. PVC pipe shall have DIP outside diameters. Joint lengths shall be at the option of the installer.

3. High density polyethylene (HDPE) pressure wastewater piping shall meet the requirements for HDPE

pipe as outlined in the MPW Water Distribution Specifications. 4. PVC gravity wastewater pipe and fittings shall conform to the requirements of ASTM specification D3034,

or D3033. Wall thickness shall be SDR-26. Saddle type fittings shall not be used.

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5. Cast iron pipe and joints shall conform to ANSI A21.1, A21.6, A21.8, A21.10 and/or A21.11. 6. CIP and DIP force main installations shall conform to ASTM A-377; AWWA C-600; 7. All metallic pipe, valves, fittings, restrainers, and appurtenances are to be wrapped in an 8-mil

polyethylene film in accordance with ANSI Standard A21.5 (AWWA C105). Close all open ends and damaged areas securely with tape. If damaged polyethylene film cannot be repaired, replace with new film.

8. Pipe or fittings constructed of the following materials are not approved in any application: ABS plastic,

vitrified clay (VC). 9. PVC pipe used in trenchless applications (horizontal directional drilling) shall be submitted to MPW

Engineering Department for approval. MPW will consider non-conventional methods of joining pipe (thermal fusion, keyed couplings, etc.) provided these methods comply with all applicable SCDHEC, AWWA, ASTM, ANSI, and the piping manufacturer’s standards.

4.1.3 Pipe Protection: 1. Pipe storage and handling shall be in accordance with the pipe manufacturer's recommendations. Pipe

shall be stored on a smooth surface to avoid point loadings. Pipe shall be handled with care so as to prevent damage. Correct equipment should be used to load or unload pipe so as to eliminate dropping.

2. Wastewater pipe which, when completed, has less than three feet of cover shall be constructed of ductile

iron pipe with an internal corrosion-proof lining and external poly-wrap as specified in Section 4.1.2. 3. Where foundation conditions are not satisfactory as determined by the soil conditions, wastewater pipe

shall be either laid on a Class B concrete cradle, pipe foundation material, or constructed of ductile iron pipe, as approved in advance by MPW.

4. Where wastewater pipe is laid under storm drainage pipe, there must be a minimum of eighteen (18")

inches of clearance. When a wastewater pipe crosses under a storm drainage pipe, the wastewater pipe should be a twenty (20') foot joint of DIP, centered under the drainage line. In cases where eighteen (18") inches of clearance is not obtainable, special provisions such as concrete encasement or casing may be approved by MPW and SCDHEC on a case by case basis.

4.1.4 Air Valves: 1. Air release valves shall be installed at high points in the force main and/or as designated by the Engineer.

The air release valves shall be designed specifically for the flows and operating pressures of the particular system and shall be equal to the Golden-Anderson Figure No. 925 long body. The air valves shall have a valve body and cover of semi-steel, with viton resilient seat, stainless steel float and linkage. An inlet isolation gate valve (brass or Type 316 stainless steel) shall be provided. All connection piping external to the air release valve shall be brass or Type 316 stainless steel. Air release valves shall be enclosed in a five-foot diameter precast manhole with a flat slab top as a minimum standard. (See Construction Detail No. 10)

2. Combination air-release vacuum valves are not allowed. 3. Submittals on air-release valves should be sent to MPW for approval before ordering material. 4.1.5 Pipe Identification and Detection: 1. All wastewater mains shall be adequately identified by color coding pipe. Pipe color-coding will be as follows: Application Pipe Color Code Wastewater System White, Green, or Brown Wastewater Force Main White, Green, or Red

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2. All wastewater mains which are installed by the open-trench method, regardless of piping material, shall

also include the installation of an electronically or magnetically detectable tape buried directly over the pipe twelve (12") inches below the ground surface continuously. The tape shall be at least two (2") inches wide, be green on top, and be boldly labeled every eighteen to thirty-two (18"- 32") inches as follows �CAUTION WASTEWATER LINE BURIED BELOW�. The tape shall have a tensile strength of no less than 4000 psi, a dart impact strength of no less than 120 grams per 1.5 mils, be no less than 0.0055 inch thick, and include sufficient metal to allow easy detection at the above stated depths. The tape shall be designed to last as long as the pipe it is installed over, even in adverse soils.

3. All wastewater force main installations, regardless of piping material, shall also include the installation of

a locator wire. The locator wire shall be taped to the top of the pipe with standard duct tape during the pipe laying operation. For wastewater mains which are installed by the open-trench method, the locator wire shall be stranded 12-gauge copper with insulation rated UF or USE by Underwriter’s Laboratories. For wastewater mains which are installed by a trenchless method (horizontal directional drilling or other), the locator wire shall be stranded 10-gauge stainless steel with insulation rated UF or USE by Underwriter’s Laboratories. Underground splice connections shall be minimized and shall be rated for direct burial service. The tracer wire shall be looped into “dummy” cast-iron water valve boxes (with caps labeled “SEWER” and painted white) installed at grade level, one being installed adjacent to the valve vault at the source pump station. Additional valve boxes shall be installed at intervals of no greater than every one thousand (1000') feet along the length of the force main (unless the main was installed by a trenchless method). A final valve box shall be installed at the discharge point of the force main, whether that be at a manhole or at a “tee” into another force main. The looped termination shall allow for the connection of an electronic locator transmitter.

4. Prior to acceptance of the wastewater force main by MPW, the Contractor shall demonstrate that the locator wire functions properly. The Contractor shall use one of several commercially available utility locating instruments to energize and trace the locator wire. Where the wastewater force main is installed in the road shoulder, green-marking flags (pin flags) shall be installed along the length of the wastewater main at intervals of no greater than twenty (20') feet. Where the force main is installed under concrete or asphalt, green marking paint shall be used. Contact MPW’s Engineering Department for a list of acceptable locating instruments. Testing of the locator wire and installation of the marking flags shall be done prior to scheduling a final inspection of the wastewater system.

4.1.6 Stop Valves: 1. Eccentric plug valves shall be used exclusively on wastewater force main projects unless specifically

authorized by MPW’s Engineering Department. Plug valves shall be used for all sizes two (2") inches and larger. All valves shall open left (counter clockwise). All plug valves shall have a 450 foot-pound gear driven actuator minimum.

2. Valves with operating nuts greater than three (3') feet deep shall have valve nut extenders provided by

the valve manufacturer bringing the operating nut to within two (2') feet of finished grade. All valves shall have a cast iron screw-type valve box and a concrete collar.

3. All valves are to be designed for a minimum working pressure of no less than 150psi. Plug valves shall

be of the non-lubricated eccentric plug type with a resilient seat seal of Buna-N or Neoprene suitable for wastewater service. Seats shall be of non-metallic with seat coating thermally bonded and in full conformance with AWWA Standard C550. Valves shall be furnished with permanent corrosion resistant bearing surfaces in the upper and lower journals designed to withstand full-rated bearing loads and provide long life in wastewater service.

4. Valves shall have their internal wetted surfaces protected by nonmetallic coatings factory applied,

thermally bonded and in full conformance with AWWA Standard C550. All valves shall be furnished with MJ ends in accordance with ANSI Standard A21.11 unless specified otherwise and approved by MPW. Port area for all valves shall be a minimum of 80% of the full pipe area. Valve bodies shall be of ASTM A-126 Class B cast iron. Nominal valve pressure ratings, body flanges and wall thickness shall be in full conformance with ANSI B16.1-1975.

5. Valves designated for direct bury shall have gear actuator with two (2") inch square operating nut and

shall be capable of opening the valve at rated pressure of 150psi. All gearing shall be fully enclosed in a

12

suitable housing and be suitable for running a lubricant with seals provided on all shafts to prevent entry of dirt and water into the actuator. A suitable stop shall be set to provide watertight shut off in the closed position at full rated pressure. Plug valves for installation in valve pits or above ground shall have hand wheel operators.

6. Valves shall be oriented so that the plug blocks the UPSTREAM port when closed. 7. Valves supplied by the following manufacturers are acceptable: Mueller Company, American Darling

Valve Company, Milliken Valve Company. 8. Valve Box: Valve boxes shall be full cast iron with cast iron covers suitable for heavy traffic use and

conform to ASTM A 48, Class 20 Specifications. Valve boxes shall be screw type and have a five and one-quarter (5.25") inch inside shaft diameter. All parts shall have an asphaltic coating inside and outside with a minimum of 1 mil dry film thickness. All castings shall be manufactured in the United States of America by East Jordan Iron Works, Inc. (EJIW), Tyler Pipe, or Bingham and Taylor. The following units are the standards for MPW: EJIW 8550 Valve Box with 14” base flange, EJIW 8500 Risers, Tyler Pipe/Utility Division #6850 Series, and Bingham and Taylor #4905 or equivalent. Each casting shall be identifiable and show, at a minimum, the following: name of the producing foundry, country of manufacture (such as “Made in USA”), ASTM A48, CL 35B, individual part number and cast or heat date. Castings shall include all lettering as shown on the specification drawings. See detail in MPW Water Distribution Specifications.

4.1.7 Check Valves: 1. All check valves at pump stations shall be HDL Ball Check Valves, Type 2016, sinking ball as

manufactured by Flygt or approved equal. Check valves shall be mounted in the vertical position only. 2. All in-line check valves at force main manifold connections shall be of the duckbill type. The port area

shall contour down to a duckbill, which shall be of one-piece rubber construction (EPDM rubber or substitute material approved for wastewater applications by MPW Engineering Dept.) with fabric reinforcement. The valve body shall be drilled and tapped for a cleanout plug on the top of the body and flushing connections on the bottom of the body. The valve shall be two-piece split body construction and a rubber gasket shall seal the two halves. In-line check valves shall be Series 39 Inline Check Valves with epoxy coating as manufactured by Red Valve Company or approved equal. Manufacturer shall have available flow test data from an accredited hydraulics laboratory to confirm pressure drop data.

3. Valve body shall be of ductile iron construction with flanged ends and shall conform to ANSI B16.1 Class

250 with flat-faced bolt holes having straddle centerlines. Port areas shall be 100% of the mating pipe port area.

4. All bolts, nuts, and fasteners shall be AISI Type 316 stainless steel. 5. All check valves shall be submitted to MPW for approval. Included with the check valve submittal shall be

an Engineer’s Certification that the head conditions available in the force main are adequate to insure proper operation of the check valve, without hammering, when the valve is installed in the position (horizontal or vertical) indicated on the plan drawings.

6. Check valves shall incorporate a clean-out port, which permits access to the inside of the valve without

removal of the valve from the line. SECTION 4.2 - EXECUTION 4.2.1 Alignment and Grade: Install the pipe (alignment and profile) as shown on the approved drawings.

Maintain a minimum depth of cover of three (3') feet unless actual depths are shown otherwise on the approved construction drawings.

Gravity wastewater line installation must comply with ANSI/ASTM D2321-74 as the minimum acceptable standard as well as any additional requirements stated herein.

4.2.2 Rights-of-way, Easements, and Permits: It is the responsibility of the developer/engineer to obtain all

necessary legal documentation and permits and advise MPW of the status of each prior to

13

commencement of work. Wastewater lines not in a dedicated road right-of-way shall be installed in a fifteen (15') foot private easement dedicated to MPW. MPW may require a wider easement for deeper lines. When water and wastewater lines are installed parallel in a dual easement, the easement width shall be increased to twenty-five (25') feet with ten (10') foot separation between pipes.

All installation work is to be conducted within the parameters stipulated in the right-of-way, easements, and permits, etc. Any damages caused by encroachment beyond the legal limits as stipulated shall be the responsibility of the developer and/or contractor. The contractor shall adhere to all special conditions on encroachment permits. Contractor is responsible for restoring right-of-way to a condition satisfactory with governing agency.

4.2.3 Bedding: 1. Before the wastewater pipe is placed in position in the trench the bottom and sides of the trench shall be

carefully prepared as per manufacturer's specifications. Each pipe shall be accurately placed to the exact line and grade called for on the plans. Laser equipment shall be used in setting pipe grades in lieu of the batter board method.

2. Pipe shall be laid in a full bed of granite stone (ASTM C33, Gradation 67), as shown in Construction

Detail No. 9. Area around pipe bell shall be hand dug to assure full support around pipe barrel. Pipe laying shall proceed up-grade, starting at the lower end of the grade with the bells up-grade. Pipe shall be straight when placed in the trench. Trench bottoms found to be at incorrect grade after pipe-laying operations have begun shall be corrected and brought to exact line and grade.

3. After each line of pipe has been laid, it shall be carefully inspected and all earth, trash, rags, and other

foreign matter removed from the interior. 4.2.4 Installation: 1. Each joint shall be laid so that it will form a close concentric joint with adjoining pipe and so as to avoid

sudden offsets. 2. All joints for pipe and fittings shall be in accordance with the pipe manufacturer's recommendations. After

the pipe has been cleaned and inspected for defects and lowered into the trench, the mating surfaces of the compression joint shall be wiped clean and coated with lubricant of a type supplied by the pipe manufacturer. The pipe shall then be assembled with due care being taken to insure that the spigot end of the pipe is seated properly and that the pipe is left at proper grade and alignment.

3. Any leaks or defects discovered at any time after completion of the work shall be repaired immediately.

All pipes in place shall be carefully protected from damage until the backfilling operations have been completed.

4. Water shall not be allowed to run through the pipe or stand in the trench. 5. Whenever pipe laying operations are to be discontinued for a period of time exceeding two hours, the end

of the pipe shall be carefully secured to avoid displacement or misalignment and a tight fitting plug or stopper shall be placed in the line. Upon resumption of laying operations, the plug or stopper shall not be removed from the line until any water; mud or other debris has been removed to avoid entry into the completed section of the wastewater system.

6. Force main wet taps will be made by MPW. Contractor shall expose lines and the tap location must be

marked. Tap procedure will be similar to section 4.3.11 of the MPW’s Water Distribution Specifications. Contractor shall be responsible for traffic control, backfilling, and asphalting around the tap area as required. Contractors shall also be responsible for proper shoring and removal of water from trench. The respective developers or contractor will be quoted tap fees at the time their construction plans are reviewed. These fees must be paid before MPW will make the tap. No discharge will be allowed into existing MPW lines until new lines (and new pump stations, if applicable) have been purged clean and have passed MPW’s Inspection.

7. On force main installations, thrust blocking or restrained joints shall be provided at all changes in

alignment greater than or equal to thirty (30°) degrees.

14

4.2.5 Cutting Pipe: Cut pipe with milling type cutter, or abrasive saw cutter. Do not flame cut or use rolling

pipe cutter. Cuts must be perpendicular to the length of pipe. Dress cut ends of pipe in accordance with manufacturer's directives for the type of joint to be made.

4.2.6 Joining Pipe: 1. General: Lay pipe on bedding such that it is continuously supported along the barrel and not bearing on

the bell. After joint construction, place bedding material under bell. Unless otherwise directed, lay pipe with bell end facing the direction the pipeline is being extended.

2. Flanged: Prior to connecting flanged pipe, the faces of the flanges shall be thoroughly cleaned of all oil,

grease, and foreign material. The rubber gaskets shall be checked for proper fit and thoroughly cleaned. Care shall be taken to ensure proper seating of the flange gasket. Bolts shall be tightened so that the pressure on the gasket is uniform. Torque-limiting wrenches shall be used to ensure uniform bearing insofar as possible. If joints leak when the hydrostatic test is applied, the gaskets shall be replaced and bolts retightened.

3. Mechanical, Push-on, and Restrained Joint: Join pipe with mechanical or push-on type joints in

accordance with the manufacturer's recommendations. Provide all special tools and devices, such as special jacks, chokers, and similar items required for proper installation. Lubricant used for the pipe gaskets shall be in accordance with the manufacturer's standard.

4. Thermally-fused Joints: Join pipe with thermally-fused joints in accordance with the manufacturer's

recommendations. Provide all special tools and devices. Depending upon the application and the manufacturer’s recommendation, MPW may require that the extruded bead of pipe material be removed from the exterior and/or the interior of the pipe prior to installation of the pipe.

4.2.7 Deflection: The maximum permissible deflection at joints shall be 75% of the maximum allowed by

AWWA Standard C600, Tables 5 and 6. 4.2.8 Polyethylene Encasement of All Metallic Pipes: All metallic pipe, valves, fittings, restrainers, and

appurtenances are to be wrapped in a 8 mil polyethylene film in accordance with ANSI Standard A21.5 (AWWA C105). Close all open ends and damaged areas securely with tape. If damaged polyethylene film cannot be repaired, replace with new film.

4.2.9 Anchorage: 1. General: All tees, plugs, caps and bends which are equal to or greater than eleven and one-quarter

(11.25°) degrees, and at other locations where unbalanced forces exist, shall be securely anchored by acceptable thrust blocking, restrained joints or a combination of both. See thrust block details in MPW’s Water Distribution Specifications

2. Blocking: The concrete mix used for thrust blocking shall have a 28-day compressive strength of no less

than 3,000 pounds per square inch. Place blocking between the undisturbed ground and the fitting to be anchored. Place the blocking so that the pipe and fitting joints will be accessible for repairs, unless otherwise shown. Thrust blocking is required on all water lines greater than two and one-half (2.5") inches in diameter. Thrust blocking must also be installed on all lines two and one-half (2.5") inches and smaller if the joints are of the slip-joint type.

3. Restrained Joints: EBBA Iron Sales, Megalug retainer glands or equivalent shall be used for all

mechanical joints three (3") inches and larger. Where appropriate and as designated by the Engineer or Commission, Megalug retainer glands shall be used in combination with blocking. PVC fittings with restrainers manufactured by JCM Industries (or equal) may be used subject to approval by MPW.

4.2.10 Highway Crossings: 1. General: Installation shall conform to the permits of all agencies having jurisdiction. The Engineer shall

specify Method of installation. 2. Casing Pipe: Fully weld lengths of casing pipe to the preceding section in accordance with AWS

15

recommended procedures. Clean all debris from casing interior after casing installation is complete. Pressure grouts any void areas outside the casing. After installation of the carrier pipe, close ends of the casing with four (4") inch thick brick walls, plastered with Portland cement mortar and waterproofed with a bituminous coating.

3. Casing Spacers: Casing spacers shall be prefabricated (Type 316) stainless steel with polyethylene

insulators capable of being securely fastened to the carrier piping. All attaching hardware shall be (Type 316) stainless steel. Spacing of casing spacers shall be per manufacturers specifications. Casing spacers shall be equal to those manufactured by Cascade Manufacturing.

SECTION 4.3 - TESTING MPW will require that all wastewater systems pass the following tests prior to acceptance: (MPW must be notified 72 hours before test). 4.3.1 Deflection Test: After final backfill has been in place at least 30 days, PVC wastewater pipe shall be

tested for initial diametric deflection by the use of a five (5%) percent mandrel. Prior to the test, the mandrel shall be checked and approved by a Commission Inspector using a “proving ring” of the appropriate size. The initial diametric deflection shall not exceed five (5%) percent. The Contractor shall not use any mechanical device in the mandrel pull. The contractor will be responsible to provide appropriate safety equipment to allow entry to confined spaces in accordance with State and Federal OSHA/Labor Laws and Regulations. At his discretion, MPW’s Inspector may visually inspect lines. MPW will not accept any line, which fails a mandrel pull.

4.3.2 Low Pressure Air Test for Gravity Lines: The Contractor shall conduct a low pressure air test on all

completed sections of gravity wastewater lines. The air test results will be used to evaluate materials and construction of the lines and to verify there are no leaks. The Contractor shall furnish all equipment and materials necessary to conduct test. Air testing shall conform to ASTM F-1417. The following provisions will be adhered to when conducting low-pressure air tests.

1. Equipment:

a. Air Compressor: The Contractor shall furnish an air compressor, which will provide at least three hundred cubic feet of air per minute at 100 psig.

b. Plug Design: Either mechanical or pneumatic plugs may be used. All plugs shall be designed to

resist internal testing pressures without the aid of external bracing or blocking. However, the Contractor should internally restrain or externally brace the plugs to the manhole wall as an added safety precaution throughout the test. Plugs in wastewater lines eighteen (18") inch in size and larger shall be connected by cable for thrust reaction.

c. Singular Control Panel: To facilitate test verification by the inspecting Engineer, all air used

shall pass through a single, above ground control panel.

d. Equipment Controls: The above ground air control equipment shall include a shut-off valve, pressure regulating valve, input pressure gauge, and a continuous monitoring pressure gauge having a pressure range from 0 to at least 10 psi. The continuous monitoring gauge shall be no less than four (4") inches in diameter with minimum divisions of 0.10 psi and an accuracy of +0.04 psi.

e. Separate Hoses: Two separate hoses shall be used to:

1. Connect the control panel to the sealed line for introducing low pressure air, and; 2. A separate hose connection for constant monitoring of air pressure build-up in the line.

This requirement greatly diminishes any chance for over-pressurizing the line.

f. Pneumatic Plugs: If pneumatic plugs are utilized, a separate hose shall also be required to

inflate the pneumatic plugs from the above ground control panel.

16

2. Line Preparation: During wastewater line construction all service laterals, stubs, and fittings in the wastewater test section shall be properly capped or plugged to not allow air loss that could cause an erroneous air test result. It may be necessary and is always advisable to restrain gasketed caps, plugs, or short pipe lengths with bracing stakes, clamps and tie-rods, or wire harnesses over the pipe bells.

3. Gravity Line Low-Pressure Air Test Procedure:

a. Plug Installation and Testing: After a manhole to manhole reach of pipe has been backfilled to final grade, cleaned and prepared for testing, the plugs shall be placed in the line at each manhole and secured.

It is advisable to seal test all plugs before use. Laying one length of pipe on the ground and sealing it at both ends with the plugs to be checked may accomplish seal testing. The sealed pipe should be pressurized to 9 psig. The plugs shall hold against this pressure without bracing and without any movement of the plugs out of the pipe. No persons shall be allowed in the alignment of the pipe during plug testing.

It is advisable to plug the upstream end of the line first to prevent any upstream water from collecting in the test line. This is particularly important in high groundwater situations. When plugs are being placed, the pipe penetrating the manhole shall be visually inspected to detect any evidence of shear in the pipe due to differential settlement between the pipe and the manhole. A probable point of leakage is at the junction of the manhole and the pipe, and this fault may be covered by the pipe plug, and thus not revealed by the air test.

b. Line Pressurization: Low-pressure air shall be slowly introduced into the sealed line until the internal air pressure reaches 4.0 psig greater than the pressure of the groundwater above the pipe, but not greater than 9.0 psig. MPW’s Inspector shall approve the method of determining ground water elevation.

"Test psig = 4.0 psig + [.43 x (ground water elevation - pipe elevation)]" c. Pressure Stabilization: After a constant pressure of 4.0 psig (greater than the average groundwater

pressure) is reached, the air supply shall be maintained at that internal pressure for at least 2 minutes. This time permits the temperature of the entering air to equalize with the temperature of the pipe wall.

d. Timing Pressure Loss: When the pressure has stabilized, the air hose from the control panel to the air

supply shall be shut off or disconnected. The continuous monitoring pressure gauge shall then be observed while timing the decrease in pressure. A stopwatch or other timing device (at least 99.8% accurate) will be used to time the decrease in pressure from 4 psi (greater than the average groundwater back pressure).

A predetermined duration for a specified pressure drop shall be used to determine the lines acceptability. Traditionally a 1.0-psig-pressure drop test is required. However, other pressure drop tests may be acceptable, if the duration is adjusted accordingly. If the pressure drop is 0.5 psig rather than 1.0 psig, then the duration for 1.0 psig pressure drop must be halved. Specifying a 0.5 psig pressure drop is desirable in that it can reduce the time needed to accomplish the air test without compromising the test.

e. Specified Time Tables: To facilitate the proper use of this recommended practice for air testing, the

following tables are provided. Table I contains the specified minimum times required for a 1.0 psig pressure drop from a starting pressure of at least 3.5 psig greater than the average pressure of any groundwater above the pipe's invert. Table II contains specified minimum times required for 0.5 psig pressure drop from a starting pressure of at least 3.5 psig greater than the average back pressure of any groundwater above the pipe's invert. Both tables also include easy to use formulas for calculating required test times for various pipe sizes and odd lengths.

f. Determination of Line Failure: If the time shown in Table I (or Table II), for the designated pipe size and

length, elapses before the air pressure drops 1.0 psig (or 0.5 psig); the section undergoing test shall have passed and shall be presumed to be free of defects. The test may be discontinued once the prescribed time has elapsed even though the 1.0 psig (or 0.5 psig) drop has not occurred. If the pressure drops 1.0 psig (or 0.5 psig) before the appropriate time shown in Table I (or Table II) have elapsed, the air loss rate shall be considered excessive and the section of pipe has failed the test.

17

The Contractor or Engineer shall complete MPW's test form in the presence of an MPW Inspector and submit a copy to MPW as proof of test completion.

g. Line Repair or Replacement: If the section fails to meet these requirements, the Contractor shall

determine at their own expense, the source or sources of leakage, and they shall repair or replace all defective material and/or workmanship to the satisfaction of MPW. The extent and type of repair, which may be allowed, shall be subject to the approval of MPW. The corrected pipe installation shall then be retested to meet the requirements.

4.3.3 Force Main Pressure Test: All force mains shall successfully pass a pressure test of one and one half

times the working pressure, but in no case less than 100 psi. The pressure shall hold for two (2) hours. Force main pressure testing shall comply with AWWA C-600 (DIP) or AWWA C-605 (PVC).

The following AWWA formula for allowable pressure loss will determine if a force main is acceptable:

Allowable Leakage (Gal/Hr) = L*D * P where, 133,200

L = Length of pipe tested in ft.;

D = Nominal diameter in inches;

P = Average test pressure in psig.;

The Engineer shall complete the MPW test form in the presence of an MPW Inspector and submit a copy to MPW as proof of completion.

18

TABLE I Specification Time Required for a 1.0 PSIG Pressure Drop for size and length of pipe indicated.

1 Pipe

Diameter (in.)

2

Minimum Time (min.) (sec.)

3 Length

for Minimum

Time (ft.)

4 Time for

Longer Length (sec.)

Specification Time for Length (L) Shown (min:sec)

100 ft 150 ft 200 ft 250 ft 300 ft 350 ft 400 ft 450 ft

4 3:46 597 .308L 3:46 3:46 3:46 3:46 3:46 3:46 3:46 3:46

6 5:40 398 .854L 5:40 5:40 5:40 5:40 5:40 5:40 5:42 6:24

8 7:34 298 1.520L 7:34 7:34 7:34 7:34 7:36 8:52 10:08 11:24

10 9:26 239 2.374L 9:26 9:26 9:26 9:53 11:52 13:51 15:49 17:48

12 11:20 199 3.418L 11:20 11:20 11:24 14:15 17:05 19:56 22:47 25:38

15 14:10 159 5.342L 14:10 14:10 17:48 22:15 26:42 31:09 35:36 40:04

18 17:00 133 7.692L 17:00 19:13 25:38 32:03 38:27 44:52 51:16 57:41

21 19:50 114 10.470L 19:50 26:10 34:54 43:37 52:21 61:04 69:48 78:31

24 22:40 99 13.674L 22:47 34:11 45:34 56:58 68:22 79:46 91:10 102:33

27 25:30 88 17.306L 28:51 43:16 57:41 72:07 86:32 100:57 115:22 129:48

30 28:20 80 21.366L 35:37 53:25 71:13 89:02 106:50 124:38 142:26 160:15

33 31:10 72 25:852L 43:05 64:38 86:10 107:43 129:16 150:43 172:21 193:53

36 34:00 66 30.768L 51:17 76:55 102:34 128:12 153:50 179:29 205:07 230:46

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TABLE II Specification Time Required for a 0.5 PSIG Pressure Drop for size and length of pipe indicated.

1 Pipe Diameter (in.)

2 Minimum Time (min.) (sec.)

3 Length for Minimum Time (ft.)

4 Time for Longer Length (sec.)

Specification Time for Length (L) Shown (min:sec)

100 ft 150 ft 200 ft 250 ft 300 ft 350 ft 400 ft 450 ft 4 1:53 597 .190L 1:53 1:53 1:53 1:53 1:53 1:53 1:53 1:53

6 2:50 398 .427L 2:50 2:50 2:50 2:50 2:50 2:50 2:51 3:12

8 3:47 298 .760L 3:47 3:47 3:47 3:47 3:48 4:26 5:04 5:42

10 4:43 239 1.18L 4:43 4:43 4:43 4:57 5:56 6:55 7:54 8:54 12 5:40 199 1.709L 5:40 5:40 5:42 7:08 8:33 9:58 11:24 12:50

15 7:05 159 2.671L 7:05 7:05 8:54 11:08 13:21 15:35 17:48 20.02

18 8:30 133 3.846L 8:30 9:37 12:49 16:01 19:14 22:26 25:38 28:51

21 9:55 114 5.235L 9:55 13:05 17:27 21:49 26:11 30:32 34:54 39:16 24 11:20 99 6.837L 11:24 17:57 22:48 28:30 34:11 39:53 45:35 51:17 27 12:45 88 8.653L 14:25 21:38 28:51 36:04 43:16 50:30 57:42 64:54 30 14:10 80 10.683L 17:48 26:43 35:37 44:31 53:25 62:19 71:13 80:07 33 15:35 72 12.926L 21:33 32:19 43:56 53:52 64:38 75:24 86:10 96:57 36 17:00 66 15.384L 25:39 38:28 51:17 64:06 76:55 89:44 102:34 115:23

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MPW Gravity Wastewater Low Pressure Air And Mandrel Tests Project:

Contractor

Date:

Engineer:

MH

To MH

Line Diameter:

Length:

Specified Time for Length @ 1.0 Psig

Min

Sec

@ 0.5 Psig

Min

Sec

Time:

1.

Min

Sec

Pressure

2.

Min

Sec

Pressure

3.

Min

Sec

Pressure

4.

Min

Sec

Pressure

5.

Min

Sec

Pressure

6.

Min

Sec

Pressure

Pressure Test:

Passed

Failed

Mandrel Pull:

Passed

Failed

MH

To MH

Line Diameter:

Length:

Specified Time for Length @ 1.0 Psig

Min

Sec

@ 0.5 Psig

Min

Sec

Time:

1.

Min

Sec

Pressure

2.

Min

Sec

Pressure

3.

Min

Sec

Pressure

4.

Min

Sec

Pressure

5.

Min

Sec

Pressure

6.

Min

Sec

Pressure

Pressure Test:

Passed

Failed

Mandrel Pull:

Passed

Failed

Comments: Cc:

21

MPW Force Main Pressure Test

Project:

Contractor:

Date:

Engineer:

First Hour Start Time:

Stop Time:

Start Pressure (P1)

Stop Pressure (P2)

Pipe Length (FT)

Pipe Dia (Inches)

Refill Gallons:

Average Pressure (Pavg) = P1+P2 = 2 Allowable Leakage = L*D* Pavg (Gallons/hr) 133,200 = Second Hour Start Time:

Stop Time:

Start Pressure (P1)

Stop Pressure (P2)

Pipe Length (FT)

Pipe Dia (Inches)

Refill Gallons:

Average Pressure (Pavg) = P1+P2 = 2 Allowable Leakage = L*D* Pavg (Gallons/hr) 133,200 =

Passed: Failed:

Locator Wire Performance Check: Passed: Failed: Comments CC:

22

CHAPTER 5 MANHOLES

Topics covered in this chapter include:

! Manhole construction ! Manhole frames and covers ! General considerations

SECTION 5.1 - MANHOLE CONSTRUCTION 1. Manholes shall be precast reinforced concrete manhole sections with tongue and groove joints.

Manholes shall conform to the requirements of ASTM Specification C478. Concrete used in their manufacture shall have a 28-day compressive strength of not less than 4,000 pounds per square inch and the absorption shall not exceed six (6%) percent. (See Construction Details No. 11 and No. 12)

2. The minimum sizes and wall thickness of the manhole riser sections shall be:

Wastewater Line ID Manhole ID Minimum Wall Thickness Less than 12 Inches 4' 5" 12" to 15" 5' 5" 15" to 24" 6' 6" Greater than 24" 8' 8"

Cone sections shall have a minimum wall thickness of eight (8") inches at their top.

3. Base sections shall be made with bottoms cast monolithically. The minimum thickness of the bottom shall

be six (6") inches for manholes four (4') feet in diameter; and eight (8") inch thickness for manholes with a five (5') or (6') foot diameter.

4. Suitable openings for inlet and outlet wastewater pipe shall be cast or cored into the base sections and

riser sections for drop connections. These openings shall be circular, accurately made, and located as required for each manhole. The base section shall be set on compacted pipe bedding materials twelve (12") inches in thickness. (See Construction Details No. 6 & No. 13)

5. Flexible manhole sleeves or flexible manhole entrance joints shall be installed on all pipe entering and

leaving manholes. Flexible manhole sleeves shall be of high quality synthetic rubber terminating in a substantial serrated flange of the same material. The flange shall be secured to the wall of the manhole base to form a tight water-stop. Minimum thickness of the sleeve material shall be 3/8 inch. Sleeve material shall comply with the requirements of ASTM Specification C923. Sleeves shall be secured to the wastewater pipe to make a watertight union with stainless steel strap clamps or draw bolts and nuts.

6. Manhole steps shall be constructed of steel covered with polypropylene. The minimum tread width shall

be twelve (12") inches. The steps shall incorporate two non-skid grooves and shall be of the drop-front design. Polypropylene covered steel steps shall consist of a one-half (0.5") inch diameter Grade 60 steel reinforcing rod covered by corrosion resistant polypropylene plastic. Steps shall be capable of withstanding the vertical and horizontal load test specified in ASTM C478. The steps shall incorporate traction cleats and foot guide lugs. Steps shall be spaced sixteen (16") inches apart. The top step shall not be greater than thirty-two (32") inches below the top elevation of the manhole. (See Construction Detail No. 11) Eccentric manhole cones shall have the top properly orientated so that steps are directly accessible.

7. The manhole sections may be joined with either O-ring seals or butyl rubber type sealer. If O-rings are

used, they shall conform to ASTM C443 and shall be set in a groove cast into the spigot section of each base and riser. O-rings shall be installed as recommended by the manhole manufacturer. If butyl rubber sealer is used it shall be "Ram-Nek" joint sealer or equal. "Ram-Nek" shall be set on only clean and dry surfaces and placed as recommended by the manufacturer. (See Construction Detail No. 14).

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In both cases, after manhole sections are jointed, the inside and outside of the bell and spigot joint shall be covered with a smooth tapered coat of pre-mixed non-shrink grout to a thickness of one-half (0.5") inch at the joint. In areas subjected to vibration due to road traffic, etc., a six (6") inch band of “Ram-Nek” shall be wrapped around joint on exterior surface of manhole.

8. Manhole sections shall be free from honeycomb, cracks, spalls, chips, exposed reinforcing, and broken

bells or spigots. Allowable deviation in form joints shall be 0.25". Edge of bells and spigots shall be even and straight.

9. Manhole inverts shall be constructed of cement grout and shall have the same cross-section as the invert

of the pipes, which they connect. The manhole invert shall be carefully formed to the required size and grade by gradual and even changes in sections. Changes in direction of flow through the manhole shall be made to a true curve with as large a radius as the size of the manhole will permit. Concrete brick will be used only to form the invert channel walls. All other annular space shall be filled with non-shrink concrete grout. No fillers such as broken block, gravel, sand, or excavated material is allowed in the construction of fillets (benches). Inverts shall be "U" design with top of "U" even with the crown of the pipe. Invert piping shall not extend inside manhole any further than two (2") inches. The slope of the invert benches shall provide a minimum of 2" higher than the crown of the pipe. When dissimilar pipe sizes occur, the elevation of the crown of the pipes must be the same. (See Construction Detail No. 15

SECTION 5.2 - MANHOLE FRAMES AND COVERS 1. Manhole frames and covers shall be made of cast iron conforming to ASTM Specification A-48 Class 35.

All castings shall be made accurately to the required dimensions and pattern. The castings shall be sound, smooth, clean and free from blisters and other defects. Castings, which have been plugged or otherwise repaired, shall be unacceptable for use. The contact surface between the cover and supporting ring shall be machined to make contact on the complete perimeter. There shall be no holes or perforations in the cover. Manhole tops must be above minimum 50-year flood level where possible; otherwise, watertight covers must be used. Manholes in pavement shall be even with the pavement. Watertight covers or rain stoppers shall be used in areas susceptible to periodic flooding to prevent infiltration.

Frames and covers shall be U.S. Foundry USF 480 ring and RA-SSG cover, East Jordan Iron Works 2029AVH frame and cover with wiper gasket, or equal. The side of the cover shall have a side-seal gasket (See Construction Detail No. 16).

2. Leveling and final grading of manhole frames and covers shall be accomplished by using a maximum of

three - four (4") inch concrete grade rings or two - six (6") grade rings (See Construction Detail No. 11, No. 12, & No. 13). The total number of grade rings shall not exceed twelve (12") inches in thickness. Grade rings shall be laid in a full bed of non-shrink grout and covered after laying with a smooth coating of non-shrink grout or hydraulic cement a minimum of one-half (0.5") inch thick. A maximum of three (3) courses of leveling brick are allowed in lieu of grade rings. Bricks used for adjustment shall be whole new hand burned common building brick, meeting grade MA of ASTM Specifications Designation C32, latest revision.

3. After the manhole has been set in its final position, the cast iron frame for the cover shall be carefully set

above finished grade and properly bonded to the masonry with non-shrinking cement grout or hydraulic cement. Where manholes are constructed in paved areas, sidewalks, etc., the top surface off the frame and cover shall be tilted so as to conform to the exact slope crown and grade of the existing pavement.

SECTION 5.3 - GENERAL CONSIDERATIONS 1. Manholes shall be installed: at the end of each line; at all changes in grade, size, or alignment; at all

intersections; and at distances not greater than four hundred (400') feet for gravity wastewater lines fifteen (15") inches or less, and five hundred (500') feet for gravity wastewater lines eighteen (18") inches to thirty (30") inches. Greater spacing may be permitted in larger wastewater lines. Clean outs may be

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used only for special conditions and shall not be substituted for manholes. 2. Where the difference in the invert elevation between an intersecting gravity wastewater line and a

manhole is eighteen (18") inches or more, a drop manhole shall be constructed. The Engineer may design either an outside drop or an inside drop manhole. An outside drop manhole shall be similar in construction to the standard manhole except that a drop connection of pipe and fittings of the proper size and material shall be constructed outside the manhole and supported by Class B concrete. (See Construction Detail No. 13) If the Engineer selects an inside drop manhole, the diameter of the manhole shall be increased as needed to provide adequate working room for maintenance inside the manhole. In general, the next larger diameter manhole will be required. The inside drop shall be constructed similar to that shown for a service drop in Construction Detail No. 6 except that the drop pipe shall be the same size and material as the incoming main.

3. Whenever possible service laterals shall be connected to manholes. These services shall be brought in

as close to invert elevations as possible and shall be sloped to provide a smooth transitional flow. Where services enter manholes at a height of two (2') feet or more, an inside drop shall be brought down to the bench (See Construction Detail No. 6). A 45-degree bend shall be placed on the end of the drop and cast into the bench to make a smooth transition to the invert.

4. MPW will require corrosion-proof epoxy linings for areas subject to high levels of hydrogen sulfide gas,

where a forcemain discharges into a manhole, or in any installation where corrosion of the concrete manhole structure may be expected. If a corrosion-proof structure is required, all exposed surfaces and structures, including walls, bench and invert shall be protected. The method of providing a corrosion-proof structure and the sub-contractor who will be performing this specialized work shall be submitted to the MPW Engineering Department for approval.

5. Force mains tying into manholes shall enter the manhole a vertical distance of not more than two (2') feet

above the flow line of the receiving manhole. 6. Where the work requires special stream crossings or other extraordinary conditions, or where alternate

types of construction are not covered by these specifications, the materials and construction methods shall be submitted for approval to MPW Engineering Department.

7. MPW will not permit groundwater infiltration into new manhole structures regardless of the source. Any

infiltration, which is found during a final inspection, must be corrected. Repair of leakage by any technique other than disassembly and reassembly of the leaking structure (manhole lining, chemical grouting, etc.) must be approved by the MPW Engineering Department prior to use.

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CHAPTER 6 PUMP STATIONS

Topics covered in this chapter include:

! Submittals ! Site design ! Wet well ! Aboveground valve piping ! Pumps and motors ! Electrical ! Control panel ! Spare parts ! Odor control

SECTION 6.1 - SUBMITTALS The Engineer should submit the following design calculations:

1. Station service area ultimate loading; 2. Flotation calculation (weight of station without pumps vs. uplift). 3. Cycle time calculation for average daily flow and peak flow shall be no more than four (4) cycles/hour and

ten (10) cycles/hour, respectively. 4. Provide certification that motor and control circuit will permit ten (10) cycles/hour. SECTION 6.2 - SITE DESIGN 6.2.1 Fencing of Pump Station Site: 1. Area to be fenced shall be a minimum of 48 feet by 48 feet. (See Construction Detail No. 17) 2. All fence materials shall be Class I Galvanized Coated. (See Construction Detail No. 18)

a. Fabric shall be six (6') feet high, ends twisted and barbed, commercial grade 9 gauge, two (2") inch mesh;

b. End, corner and pull posts to be 2.5" O.D.; The top of the fence post footings shall be above grade and sloped to shed water.

c. Top and line posts shall be 2.0" O.D.; d. Bottom tension wire shall be 7-gauge spring coil wire; e. Barbed wire shall be 12.5 gauge twisted line wires with four point, 14 gauge barbs spaced five (5") inch on centers. Three (3) rows of outward facing barbed wire shall be used.

3. Gate shall be a pair of 8 foot long by 7 feet high sections constructed of 2" O.D. pipe. Gate shall be

equipped with a prop post center latch and hasp assembly. Gateposts shall be 3" O.D. galvanized coated. A ground anchor cast in concrete shall be provided. Gates shall be factory fabricated and equipped with gate holdbacks. Panel shall have a horizontal brace center of fabric height.

6.2.2 Miscellaneous Site Requirements: 1. The entire site shall be covered with a weed barrier of 8 mil black polyethylene. The weed barrier shall

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extend one (1') outside the fence line. A 6" layer of F.L.B.C.compacted to 100% of the maximum dry density (Modified Proctor) shall be applied over the polyethylene sheeting. A two (2")-inch thick layer of asphalt shall be applied to the site according to the specifications listed in Chapter 9. The asphalt should also extend one (1') foot outside the fenced area.

2. A power pole should be located within the fenced area and should be located in such a manner so the

electric meter can be easily read from outside the fenced area. All power lines within the site shall be underground. No overhead power line will be allowed to cross the site.

3. The site shall be serviced by an asphalt road constructed above the twenty-five (25) year flood elevation

according to the specifications given in Chapter 9. Road and site drainage shall be included and approved by appropriate agency. (See Construction Detail No. 17)

4. Adequate lighting for the interior of the fenced area of the site shall be provided with a switch at the

control panel on a separate circuit. 5. A Woodford-Iowa Model Y-34 yard hydrants supplied by a three-quarter (3/4") inch potable water supply

with a standard curb stop and a SCDHEC-approved reduced-pressure (RP) backflow preventer must be installed inside the fence.

SECTION 6.3 - WET WELL 1. Minimum allowable wet well diameter shall be six (6') feet (See Construction Detail No. 19). 2. Depth of wet well shall be set to accommodate the following level control system parameters:

a. Off: Set above the pump impeller. b. Lead-lag differential of a minimum of one (1') foot. c. Telemetry alarms setting one (1') foot above the lag setting. d. Audible alarm set above telemetry alarm. e. Influent pipes a minimum of six (6") inches above the alarm setting.

3. The bottom slab of the wet well shall be set on a minimum of eighteen (18") inches of gravel. All over-

excavated areas greater than eighteen (18") inches below the wet well bottom shall be filled with Class B concrete.

4. If a wastewater force main enters the wet well, a 90° fitting and stub shall be installed to turn the flow

toward the invert, and the interior surface of wet well shall be treated with a corrosion-resistant coating approved by the MPW Engineering Department.

5. Top of slab shall be one (1') foot above the 100-year flood elevation, or special flood proofing

considerations, as approved by MPW will be required. 6. Steps should NOT be used in wet wells. 7. Gravity wastewater influent line shall have a tee and a stub installed. Access hatch and hook for hoisting

cable shall be cast into the top of wet well (See Construction Detail No. 19). 8. Hatches shall be of the specific clear opening sizes indicated for each specific pump station and shall be

Series FIR (Floodtight) Access Hatch with Fall Protection Grating as manufactured by Halliday Products, Inc., Orlando, FL, or equal. Sealing and anchorage shall be by a full flange width Ken Seal, Ram-Nek or approved equal. Mounting bolts and expansion shields shall be AISI Type 316 stainless steel. The hatch material shall be 6063-T6, 0.25 inch thick aluminum alloy diamond plate reinforced to withstand a ten (10') foot column of standing water. The door shall incorporate a 90° return flange around the perimeter. Stainless steel pressure locks shall be provided to work in conjunction with a 1/4 thick neoprene compression gasket mounted to the under side of the door. Door shall open to 90° and automatically lock with a Type 316 stainless steel hold open arm with aluminum release handle. Handle, hinges, and all

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fastening hardware shall be Type 316 stainless steel. Unit shall lock with pad lock lugs. Unit shall carry a lifetime guarantee against defects in materials and workmanship. (See Construction Detail No. 20)

9. Each pump discharge line shall have a Type 39 Dresser Coupling (or approved equal) with T316

stainless steel bolts, which is located in a manner that facilitates removal of riser pipe. 10. Vent pipe shall be ductile iron and contain 0.125-inch mesh, Type 316 stainless steel bug screen. 11. MPW will require corrosion-proof epoxy linings for areas subject to high levels of hydrogen sulfide gas,

where a forcemain discharges into a wet well, or in any installation where corrosion of any structure may be expected. If a corrosion-proof coating is required, all exposed surfaces and structures, including walls and underside of top slab, riser piping, and metallic influent piping inside wet well shall be protected. The method of providing a corrosion-proof structures and the sub-contractor who will be performing this specialized work shall be submitted to the MPW Engineering Department for approval.

SECTION 6.4 - ABOVE-GROUND VALVES AND PIPING 1. Pump station shall be equipped with aboveground valve piping as shown in Construction Detail No. 21. 2. Each pump discharge riser pipe shall be equipped with a Flygt ball check valve or approved equal. 3. A Golden-Anderson Figure 925 (150psi working pressure) air release valve (or approved equal) shall be

provided with discharge piped into wet well. Discharge piping shall be one-half (½”) inch threaded, T-316 stainless steel, with a minimum of one (1) pipe union to facilitate removal of the piping. Flushing attachments are not required.

4. Eccentric plug valves with gear driven actuators shall be used exclusively on force mains two (2") inches

and larger. All plug valves shall meet the minimum requirements provided in Chapter 4. 5. A tee shall be located between the pump discharge plug valves and the force main plug valve with the tee

turned horizontally. Provide a male quick disconnect fitting for bypass with plug valve to isolate flow. Quick disconnect should be of a “cam-lock” style, which is, compatible with that used by the MPW Maintenance Department.

SECTION 6.5 - PUMPS AND MOTORS (SUBMERSIBLE STATIONS) 6.5.1 Acceptable Pump Manufacturers for Submersible Pumps: 1. Flygt 2. ABS 3. KSB 4. ENPO (Barnes) 6.5.2 Specifications for Pumps and Motors: 1. Submersible pumps shall be manufactured in accordance with ISO 9000 quality assurance standards.

Certified tests shall be performed on the actual assembled pumps to be supplied. These tests shall be performed in accordance with the Test Code for Centrifugal Pumps per the Standards of the Hydraulic Institute. Tests shall cover a range from shut-off to a minimum of twenty (20%) percent beyond the specified design performance capacity. The test conducted on all supplied pumps shall be certified and generate a curve showing actual flow, head, BHP and hydraulic efficiency. These test curves shall be submitted to the design engineer for approval prior to shipping.

2. Pumps shall be designed to handle peak flow with the largest pump out of service, and shall be capable of

passing at minimum a three (3") inch spherical solid.

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3. Motors shall be non-overloading over the entire pumping range. 4. Motors shall be dry, squirrel cage in design, having at minimum class "F" (155 degree C) insulation and with

class "B" (130 degree C) motor temperature. The motor shall further have at minimum a 1.1 service factor and not exceed 1800 RPM. The motor shall be designed for continuous duty at 40 degrees C ambient temperature.

5. Three phase power shall be required on all motors 4.5 HP and above. No "add-a-phase" systems shall be

allowed. 6. Unbalanced voltage on motors under load shall not exceed 1.0% when measured at the motor terminals.

Voltage shall be read with an accurate digital voltmeter; and recorded as part of the final inspection; calibration shall be NEMA Standard MG1-1972.

7. High efficiency motors shall be used in all cases. 8. Lightning arrester is required for all services. 9. The motor and pump shall have a shaft of at minimum 400 series stainless or ASTM A 576 GR 1045 carbon

steel that is completely isolated from the pump media by a mechanical seal. No other materials shall be acceptable for this application.

10. Impellers shall be non-clog in design and be secured from rotation on the shaft through the use of a shaft key

or locking collar. 11. Pump volutes shall be of at minimum ASTM A 48 class 30B cast iron having a minimum Brinell hardness

rating of 180. The volute shall further be protected from wear through the use of a replaceable wear ring. Lesser grades of cast iron or materials having a Brinell hardness rating less than 180 shall not be acceptable as compatible with the normal grit contaminate of the service.

12. Lower seals shall be tungsten carbide (or silicon carbide) to tungsten carbide (or silicon carbide). No carbon

seals will be allowed. Pumps shall be equipped with a plug on the outside of the oil chamber, in order to inspect lower seal condition.

13. Bearings shall be grease lubricated and have a B-10 bearing life of at minimum 40,000 hours. B-10 bearing

lives of less value shall not be accepted as compatible with the normal overall station life expectancies. 14. All piping shall be Class 53 DIP and all fittings shall be lined and conform to ANSI/ASTM D1248. All valves

shall be resilient seat gate valves having "open-right" stem operation. 6.5.3 Pump Removal: Pumps and motors shall be installed on a Type 316 stainless steel guide rail system for

easy removal. Pumps and motors shall have an adequately sized stainless steel chain of sufficient length to reach to the top of the wet well plus an additional six (6') feet. Adequately designed lift chain hooks (2) shall be imbedded into top slab and situated to facilitate easy removal of units (See Construction Detail No. 19).

6.5.4 Motor Requirements: 1. The motor shall be protected from moisture intrusion from the pumps hydraulic end through the use of, at

minimum, two completely independent and separate mechanical seals each having its own independent pressure compensating, compression spring. Further, the outboard seal shall have at minimum two faces each of tungsten. Motor/pump sealing systems not incorporating these minimum design features shall not be acceptable as compatible with the service.

2. The motor and motor housing shall be designed for use in domestic wastewater. Further, the motor shall

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be protected from water intrusion through the use of a sealed cable entry system, which shall include a grommet flanked by stainless steel washers. The cable shall be attached to the terminal board, which is isolated from the motor housing by o-rings. The system shall positively stop water from intruding into the pump through the cable if the cable is damaged below water level. The moisture detection shall be connected to a moisture detection lamp mounted on the control panel. Moisture detection shall cause motor shutdown.

3. Motor shall be equipped with overheat sensor which will shutdown motor should an overheat condition

occur. Control panel shall have separate indicator lamp for overheat shut down. 4. Motor shall be wired for lead-lag operation and shall be equipped for alternate cycle operation. Motor

starters shall be NEMA rated. 5. Each motor will be protected by an adjustable, electronic overload relay (Furnass ESP Series), meeting

NEMA Class 10 tripping characteristics and shall be temperature compensated. The U.L. listed overload relay will be approved for use in control panels. The control auxiliary contact of the overload relay must be connected in series with the motor contactor coil to switch off the contactor in the event of overload.

SECTION 6.6 - ELECTRICAL 1. A licensed electrician shall perform all electrical work. All installations shall be in accordance with National

Electrical Code. Electrical permit shall be applied for at Town of Mount Pleasant Building Department. 2. All electrical cables from the motor and wet well level sensors shall be terminated in a PVC weather tight box.

No junction box shall be installed in wet well. (See Construction Detail 22) 3. Conduit shall be PVC Schedule 40 leaving the electrical terminal box and shall have a gas tight seal. The

seal shall consist of a layer of Chico A3 Sealing Compound poured to a thickness no greater than ¼” (one-fourth inch) to insure a gas-tight seal and to facilitate future removal. The void space below the seal layer shall be filled with any suitable packing to prevent the intrusion of the sealing compound into the body of the seal-off fitting.

4. The wet well level backup float hanger shall be stainless steel and shall be located at the edge of the hatch. 5. The ultrasonic level transducer shall be supported with a Self-Leveling, chain-type hanger (Pendant

Transducer Support by RCI Enterprises or equal, T-316SS) secured to the edge of the hatch opening in a location where it can be serviced without entering the wet well. All hardware and conduit, which is supplied as part of the transducer installation, shall be corrosion-proof.

6. Electrical control panel shall be NEMA 4X, T-316 stainless steel. Panel shall be large enough to house all

control equipment, shall have a stainless steel hasp and hinge with 3/8" diameter hole; shall have a separate lockable weatherproof main disconnect adjacent to the control panel. Panel must have watertight gasket on a hinged outer door. No bolt-on outer doors will be accepted.

7. Pump and motor shall be shipped with non-wicking electrical power cable, over-heat cable and seal failure

cable, factory installed and tested. Cut ends are to be sealed and tagged at the factory for shipping. 8. Contractor shall leave a space on the control panel mounting bracket approximately 20" x 20" to permit the

installation of a telemetry unit. Penetrations in the main control box shall be provided for a power feed and a sensor feed to the telemetry unit.

9. Electrical control panel bracket shall be made entirely of aluminum above ground and adequately grounded

(See Construction Detail No. 22). 10. Concrete pad shall be provided for the electrical control panel and extend a minimum of three (3') feet -

measured from the front edge of the open door.

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11. Provide quick connect receptacle for emergency generator and manual transfer switch or walking beam

breaker assembly (See Construction Detail No. 23). Properly match the generator receptacle to the voltage of the station: 100A, 240V stations use Hubbell No. 4100B9W receptacle; 200A, 480V stations use Crouse-Hinds AREA 20425 receptacle.

12. Provide a non-fused service disconnect (in separate NEMA 4X T-316SS box) between the electrical utility

meter and the MPW equipment (See Construction Detail No. 23) 13. Engineer shall submit a detailed pump station design package to MPW Engineering Support Division

Manager for approval. This package shall consist of, as a minimum, pump station design calculations, pump curves (showing design operating point), manufacturer’s “cut sheets” for ALL pump station components including control panel components, and complete, detailed electrical schematics showing ALL installed electrical components. Incomplete submittal packages will be returned without review. The Engineer’s pump station design shall reflect proper consideration for pump operating efficiency and future upgrade capability.

SECTION 6.7 - CONTROL PANEL Enclosure shall be NEMA 4X T-316 stainless steel with latches (easy opening without tools) and padlocking provisions. In Zone V flood areas, 6 FP enclosures shall be used. Control panels may be mounted on aluminum tubing as shown on Construction Detail No. 22. NOTE: there shall be no penetrations in the top of the control panel. 6.7.1 Control Panel Components: A minimum of the following components shall be installed on the inner door: 1. Milltronics Hydroranger Plus level controller (Wall-Mount ONLY) 2. Oil-tight HOA (Hand, Off, Auto) selector switches 3. Lead 1, Lead 2 Automatic-selector switch. 4. Six (6) digit, none reset, pump elapsed time meters. All pilot devices shall be heavy-duty 30MM corrosion

resistant Furnas Class 52X or pre-approved equal.

5. Indicating LED’s for: g1 pump running g2 seal alarm

g3 motor failure (over-temperature pump breaker-overload tripped) g4 high level alarm g5 float levels

NOTE: Indicating light shall be Furnas Class 52X with 6.3 volt or 24 volt LED bulbs.

6. Pushbuttons for: h1 test float level switches h2 alarm horn silence h3 reset-motor over temperature

h4 test seal alarm 7. GF2i Duplex Receptacle 20A mounted on the exterior of the control panel with a weatherproof cover.

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6.7.2 Mounting Backplate: A minimum of the following components shall be mounted at the backplate: 1. Fuseless combination starters with instantaneous short circuit protection, heavy duty industrial contactors

(D.P. contactors are not acceptable), 3-Phase, adjustable, electronic overload protection (Furnas ESP 100), and NEMA rated starters (Furnas or pre-approved equal).

2. Control circuit transformer 115v with primary circuit breaker and secondary circuit breakers for:

b1 Control b2 Duplex receptacle b3 Yard light b4 SCADA

Note: Backup floats must operate on 24 volt AC power.

3. Lightning arrestor 4. Power terminals, boards, and control terminals shall be of adequate size. 5. SCADA terminal shall be provided as follows:

a. SCADA system power with 6 AMP fuse; b. Pump running; c. Pump Failure (overload, circuit breaker trip, over-temperature); d. Transfer switch in emergency mode; e. High level alarm (telemetry); h. Power trouble (phase loss, low voltage); i. Control power loss; j. High level alarm (audible); k. Wet well level (4-20mA)

8. Condensation protective space heater with thermostat. 9. Phase failure relay with a (2-second) delay trip and a 60 second delay on time, which will monitor:

Phase Failure Low Voltage (Brown Out)

10. The backup float control system shall incorporate a feature that will send a SCADA high-level alarm in the

event a float failure occurs.

11. Control relays shall be intrinsically safe and have pilot lights. 6.7.3 Station Alarm Light and Horn: 1. An alarm horn and a flashing alarm light with a minimum of a 40-watt light bulb shall be installed at the

panel (not on top) and located so as to be readily visible from main road. Alarm light shall be approved for vapor tight side installation. The alarm horn shall have provisions for continuous or timed operation.

2. Alarm light and horn shall be on at high level.

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3. Provide a separate 12-volt light and horn with 12-volt battery and charger to fit inside control panel. The

battery shall have capacity for a minimum of twelve (12) hours of continuous operation. 6.7.4 Miscellaneous Control Requirements: 1. Control sequence shall be designed so that panel will function automatically following a power failure, and

manual reset is not necessary. 2. Primary wet well level control shall be via an ultrasonic controller. Ultrasonic control equipment shall be

installed inside the main control panel and shall consist of a complete HydroRanger Plus (wall mount only) system manufactured by Milltronics. The system shall include a separate hand-held 20-key programmer and cabinet-mounted custom graphics LCD indicator screen and a wet-well mounted ultrasonic transducer, Model XPS-15 Echomax as manufactured by Milltronics.

3. Transducer shall be provided with sufficient cable (30’ minimum) to reach from the wet well to the control

panel without splices. 4. Hydroranger relays #1 and #2 shall be configured for alternate duty assist. Relay #3 shall be configured

for High Level Telemetry Alarm (for use by MPW). Relay #4 shall be left as a spare. 5. A backup 24-volt float control system shall be provided to allow both pumps to operated upon primary

level control failure. The High Level Audible Alarm float shall start the pumps if the wet well level exceeds the primary level controllers High Level (Telemetry). The pumps will shut off at the backup Low Level Float.

6. Sensor floats shall be mercury-free; 7. Seal failure relays shall be with a maximum of 24 volt, O.5mA, 5VA Signal Power. Provide seal fail

indicator light in control panel. 8. Control wire to be MTW 90 degree C #14 AWG. 9. All wiring should be neatly routed in plastic wire troughs except that wiring from the backplate to the door

shall be done in separate bundled harnesses for control, voltmeter and ammeter circuits. All wires shall have a wrap-around wire identification number as shown in the wiring diagram at both ends. All components shall be identified with the same number as shown in the wiring diagram. All door mount components shall have engraved nameplates. Also included in the control panel shall be a schematic, terminal board legend, and an overload heater table. These should be secured to the inside of the door and have a weather protective coating.

10. All conduits into the control panel must be sealed. (See Construction Detail No. 22) 11. Electrical supply, control and alarm circuits shall be designed to provide strain relief and to allow

disconnection from outside the wet well. Terminals and connectors shall be protected from corrosion by being located outside of the wet well or through the use of watertight seals. If located outside, weatherproof equipment shall be used.

12. The motor control center shall be located outside the wet well and be protected by a conduit seal or other

appropriate measures meeting the requirements of the National Electrical Code, to prevent the atmosphere of the wet well from gaining access to the control center. Motor starters shall be NEMA rated. The U.L. listed NEMA sized motor contactor must have guaranteed component life span of 3 million operations without maintenance or contact replacement. (Definite purpose contactors will not be allowed).

13. Voltage to floats shall be limited to twenty-four (24) volts maximum.

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14. Pump station generator hookups shall be provided as shown in Construction Detail No. 23. SECTION 6.8 - SPARE PARTS FOR SUBMERSIBLE PUMP STATIONS: Contractor shall furnish on or before final inspection one (1) each of the following: 1. Seal assemblies - top and bottom. 2. Bearings; one (1) complete set of bearings for one pump. 3. Three (3) complete sets of record drawings for wet wells, electrical, electronic schematics (and O&M

Manuals, with factory pump curves for pumps installed), copies of all certified test and inspection data and termination schedule.

4. Two (2) of each type of fuse

Two (2) of each type of LED bulb 5. One (1) ultrasonic level transducer (cable length 30’ minimum) and two (2) mechanical floats of the same

type as supplied in the wet well. 6. Pump O-ring and gasket kit. 7. Model 3753 Master Padlock #2 provided for the following:

a. Entry Gate b. Wet Well and Valve Pit c. All Electrical Controls (Control Box, Main Breaker Disconnect, Telemetry, etc.)

8. Forty (40') foot aluminum extension ladder rated at 250lb capacity or greater. NOTE: ITEM�S 7 AND 8 ABOVE ARE ONLY REQUIRED FOR NEW PUMP STATIONS INSTALLED BY DEVELOPERS SECTION 6.9 - ODOR CONTROL MPW may install an odor control unit at any pump station which may generate odors at any time during its design life. Odors can be caused by any condition which may encourage the formation and release of hydrogen sulfide gas including a forcemain discharge into a wet well, low wastewater flow and resulting extended detention times, or other conditions. The odor-control unit shall incorporate current “state of the art” technology and shall be manufactured by a company with at least a 5-year record of successful installations. Acceptable odor-control unit manufacturers shall be BioCube or BioRem or approved equal. The following items are general guidelines. The odor control unit shall be approved by the MPW Engineering Dept. prior to installation. 1. The primary odor control unit shall incorporate a biological odor-removal process which has been shown

to effectively remove odor-causing materials of a type and concentration expected to be present at the pump station.

2. A physico-chemical process (activated carbon, etc.) shall only be used as a secondary polishing step

downstream of the biological process; 3. The biological process and any other media shall provide a minimum 5-year service life (covered by a

manufacturer’s warranty);

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4. All equipment shall be constructed of corrosion-proof materials; all electrical equipment shall comply with Section 6.6 of this document.

5. The odor control system shall be a “turn-key” installation with all necessary electrical and water supply

necessary provided by the contractor. If needed, water supply can be provided via a connection to the yard hydrant service line (See Construction Detail 17). Provision should be made for the installation of a water meter by MPW.

6. Operation of the odor control unit shall be automatic, with only periodic input or inspection by MPW

service personnel; 7. The odor control manufacturer shall provide on-site startup services which shall be coordinated with the

pump station startup if appropriate. 8. The odor control manufacturer shall provide analysis and evaluation of the biological media and process

for a minimum of 1-year following startup (free of charge). 9. A concrete slab shall be provided for the odor control equipment (submit concrete slab detail drawings for

approval). The concrete slab shall fit within the pump station site, or an additional fenced area shall be provided.

10. Three (3) complete sets of record drawings for the odor control unit shall be provided including ,

electronic schematics and O&M Manuals copies of all certified test and inspection data and termination schedule.

35

MPW Pump Station Final Inspection List

Location: Date: SITE:

YES NO

1. Fenced Area with 6' chain link fence, size in accordance with design drawings Three rows of barbed wire on top. (If wooden, agreement has been executed.) 2. Gate opening is 16' minimum 3. Black polyethylene under 6" base course and 2" asphalt 4. No overhead power crossing the site. 5. Paved road above 25-year flood elevation with adequate turning radius. 6. Overhead light provides adequate lighting to the wet well and valve pit. 7. Water service inside of fence (3/4") with approved backflow preventer. WET WELL: 1. Diameter in accordance with approved plans. 2. Top of slab above the 100 year flood elevation. 3. Influent line with tee. 4. All stainless steel inside of the wet well. 5. If force main penetrates wet well, approved anti-corrosive coating applied. 6. Vent with screen VALVES AND PIPING 1. Each pump discharge line has a Dresser-Coupling, a ball check valve, a plug valve, 2. Valve is on the force main to prevent back flow. 3. There is a tee with a male cam-lock connect for a bypass pump 4. Approved air-release with ½” SS discharge piped to wet well and pipe union provided ELECTRICAL 1. No junction box in wet well. 2. Stainless steel NEMA 4X control panel, with hinged door and no penetrations in top. 3. Is control panel flood zone? 4. Control panel bracket is aluminum. 5. Quick connect receptacle for emergency generator and the manual transfer switch (matched to

voltage)

6. Alarm (audible and visual). 7. Separate power supply for the alarm and float systems. 8. Conduits into the control panel are sealed. 9. Electrical As-Builts. 10. Electrical schematics on inner door of control panel 11. Main (service) disconnect between electrical utility meter and MPW equipment GENERAL 1. Were the spare parts provided? i.e. pump seal assemblies - top and bottom, set of bearings for one

pump spare LED bulbs, two (2) floats, O-ring and gasket kit, Ultrasonic transducer,

2. Ladder, 40', aluminum extension, 250# capacity 3. Manual hoist and socket (10 horsepower pumps and smaller) Comments: MPW Inspector: MPW Electrical Department: MPW WW Maint. Dept.:

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Mount Pleasant Waterworks

Pump Station Test Data

Attach Manufacturer’s Certified Pump Test Data and field data obtained by pump manufacturer’s representative.

Motor Amperage L1-L2 L2-L3 L1-L3

Pump No. 1

Pump No. 2

Pump No. 3

Required Information A. Wet well diameter

B. Total feet well pumped down

C. Pump run time (minutes)

(A2) (5.87) (B) = ______________GPM

C Run Start time Stop time Elapsed

Time (min) Water Level

Start Water Level

Start Total Feet GPM

1

2

3

4

5

6

7

8

Comments

Passed [ ] Contractor: Engineer: Failed [ ] MPW Inspector: Date: CC:

37

CHAPTER 7 GRINDER PUMP STATIONS

Topics covered in this chapter include: ! General conditions ! Duplex station requirements ! Simplex station requirements SECTION 7.1 - GENERAL CONDITIONS 1. Under conditions that arise from time to time, where normal installations cannot be implemented, the MPW

Engineering Department will review Submittals for a grinder station installation. Under most situations these stations will remain the property of the owner/developer. In accordance with MPW’s Guidelines for Development, a Maintenance Agreement (Appendix 26 of the Guidelines) must be executed with MPW. Permitting for pump stations shall be in accordance with SCDHEC requirements.

2. A grinder pump station which discharges (manifolds) to another MPW wastewater force main will require

that a Construction Permit Application be submitted to SCDHEC. This application shall include design calculations prepared and stamped by an SC Registered Professional Engineer. A grinder pump station which discharges directly to a MPW gravity wastewater system does not require a SCDHEC Construction Permit.

3. Testing requirements for all grinder pump stations and associated force mains are the same as those

presented in Chapters 4 and 6 of this document, and shall be witness by an MPW Inspector or his designated representative.

SECTION 7.2 - DUPLEX STATION REQUIREMENTS (FOR MULTIPLE USERS - 2 REU'S OR MORE) 1. Duplex station shall be provided with guide rails. 2. To overcome required head pressures, motors shall be adequately sized. (Minimum of two (2)

horsepower). 3. Only ABS Piranha E-2, Meyers, KSB, Hydromatic, Flygt, or Barnes (ENPO) pumps will be allowed. Note: Distributors for these pumps are: Pumps, Parts & Service, Charlotte, NC; Duty & Associates, NC;

Mechanical Equipment, Mathews, NC; Hughes Supply, N. Charleston, SC; Bisanco International, Inc., Columbia, SC

4. A minimum of four (4') foot diameter precast concrete or fiberglass wet well may be used. Installation

must include method to prevent flotation. 5. Separate valve box (locking type) with gate valves and check valves. 6. If the Developer wishes to Deed the pump station and site to MPW, and MPW agrees to accept it,

Developer shall provide MPW with a spare pump for inventory. Pumps shall have a minimum warranty of two (2) years.

7. All installations shall be in accordance with National Electrical Code. A licensed electrician shall perform

all electrical work. All wire shall have a wrap around wire identification number as shown in the wiring diagram at both ends. All components shall be identified with the same number as shown in the wiring diagram.

8. Electrical requirements shall be in accordance with Section 6.6. Control Panel requirements shall be in

accordance with Section 6.7. Motor requirements shall be in accordance with Section 6.5.4.

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SECTION 7.3 - SIMPLEX STATION REQUIREMENTS (INDIVIDUAL HOMEOWNERS) 1. Simplex station shall be provided with guide rails. 2. To overcome required head pressures, motors shall be adequately sized (Minimum of two (2) horse

power). 3. Only ABS Piranha E-2, Meyers, KSB, Hydromatic, Flygt, or ENPO ( Barnes) pumps will be allowed. 4. A minimum thirty (30") inch diameter and five (5') foot deep precast concrete or fiberglass wet well may

be used. Installation must include a method to prevent flotation. 4. All installations shall be in accordance with the National Electrical Code. A licensed electrician shall

perform all electrical work. 5. Unless wiring is clearly color-coded (as indicated on the wiring diagram), all wires shall have a

wraparound wire identification number as shown in the wiring diagram at both ends. All components shall be identified with the same number as shown in the wiring diagram. Wiring diagram shall be mounted to the inside of control panel door and shall be protected from weather by coating or plastic envelope.

6. Except as specified below, the electrical controls for single-phase pumps shall be mounted in NEMA 4X

enclosure. Single-phase power shall be 115/230V, 60 HZ, 3-wire neutral ground system. All conduits to and from the pump shall be sealed and protected against water penetration.

7. Control panels shall be supplied by the selected pump manufacturer and should consist of the following

components

a. The control panel must be weatherproof, type NEMA 4X construction, stainless steel or fiberglass. b. The outer door shall be completely gasketed, hinged and equipped with a padlockable latch. The

cover shall be hinged with a heavy-duty corrosion resistant stainless steel piano hinge. The enclosure shall be provided with back-panel mounting provisions.

c. A main disconnect breaker shall be provided to de-energize the control panel. d. The panel shall include a fused alarm circuit, fused control circuit, I.E.C. rated motor contactor,

Klixon overload, pump hand-off-auto switch, pump run light, seal leak light, start and run capacitors, start relay, terminal blocks, ground lug and all necessary wiring and brackets.

e. Maximum voltage to the floats shall be twenty-four (24) volts.

f. The control panel shall be fitted with an integral red (40 watt minimum) flashing bulb, and tamper

proof alarm light. The light shall be mounted on top of the enclosure with a neoprene gasket. The alarm light shall flash during high-water conditions and must be visible and not blocked from view by shrubbery or any other obstruction. The alarm light will go out when the water level drops.

g. There shall be an electronic seal alarm-monitoring relay installed with seal fail light indicator.

h. A schematic diagram shall be permanently fastened to the inside of the enclosure. An Installation

and Service Manual shall also be included with each control panel.

i. The control panel shall be U.L. listed as an assembly. 8. Three floats shall control the pump. The operational sequence shall be:

a. Pump off b. Pump on c. High level alarm

39

CHAPTER 8

RECLAIMED WASTEWATER SYSTEMS Topics covered in this chapter include: ! Distribution system ! Valves and valve boxes ! Service connections ! Dedicated spray irrigation sites MPW will provide non-potable, reclaimed wastewater effluent with secondary treatment and disinfection. Reclaimed effluent shall not be used for drinking, food preparation, hand washing, automobile washing, or irrigation of fruits and vegetables. SECTION 8.1 - DISTRIBUTION SYSTEM 8.1.1 Line Design Requirements: Pipe for reclaimed wastewater system shall normally be polyvinyl chloride

(PVC) or ductile iron (DIP), conforming to the most recent revision of AWWA Standards C-900 and C-151, respectively. The design of the pipe for internal pressures and external loads shall conform to the requirements of the respective AWWA Standard. However, minimum thickness class for PVC pipe shall be DR 18 and for DI pipe Class 50.

Pipe, fittings and valves shall conform to the latest standards issued by the AWWA, and be acceptable to MPW.

1. Pipe Diameters: Pipe sizing shall be supported by hydraulic analysis (and future water use) as

applicable. The minimum size of mains installed shall be four (4") inches in diameter, with the following exceptions. Mains two (2") inches in diameter will only be allowed by approval of MPW and in no case will be allowed for any extension that can, at present or by future extension, possibly serve more than ten (10) domestic customers on a cul-de-sac or twenty (20) domestic customers on a line that is connected at both ends. Where the main is looped, two (2") inch mains shall be connected at each end to a main four (4") inches or larger in diameter. A two (2") main shall be looped to a main four (4") inches or larger in diameter in a cul-de-sac.

2. Depth Requirement: All mains shall have a minimum cover over the top of the pipe of thirty (30") inches

from the proposed finished grade and a maximum depth of thirty-six (36") inches from the finished grade, except where special vertical separation conditions govern. MPW must approve any deviations.

8.1.2 Minimum Separation: 1. Horizontal Separation: Reclaimed wastewater lines mains shall be laid at least 10 feet horizontally from

any existing or proposed potable water main or sanitary wastewater lines. The distance shall be measured edge to edge. In cases where it is not practical to maintain a ten-foot separation, MPW may allow deviation on a case-by-case basis. Such deviation may allow installation of the reclaimed wastewater lines main closer to a potable water main or wastewater lines, provided that the reclaimed wastewater lines main is laid in a separate trench.

2. Vertical Separation: Reclaimed wastewater mains crossing potable water mains and sanitary

wastewater lines shall be laid to provide a minimum vertical distance of 18-inches from outside edge of pipe to outside edge of pipe. This shall be the case where the reclaimed wastewater mains are either above or below the potable water main or wastewater lines. At crossings, potable water, reclaimed wastewater lines and wastewater pipe shall be ductile iron pipe, and one full length of reclaimed wastewater lines shall be located so both joints will be as far from the water main and wastewater lines as possible. Water, wastewater lines and reclaimed wastewater lines shall normally be located from the street surface in the order of: potable water, reclaimed wastewater lines, and sanitary wastewater lines.

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8.1.3 Pipe Identification and Detection: 1. All reclaimed wastewater mains shall be adequately identified by color coding pipe and with an approved

marking scheme. For pipes ten (10") inches or larger, there shall be a minimum of three colored stripes per length of pipe (located at 10 o’clock, 2 o’clock, and 12 o’clock when the pipe is installed) each a minimum of one (1") inch wide and the pipe description shall appear one or more times every 36 inches in one (1") inch wide letters. For pipes small than ten (10") inches there shall be a minimum of one two (2") inch wide colored stripe along the entire length of pipe (located at 12 o’clock when the pipe is installed) and the pipe description shall appear one or more times every thirty-six (36") inches in one (1") inch wide letters.

Pipe description shall be:

Application Pipe Color Description

Reclaimed Wastewater Purple “Reclaimed Wastewater” 2. All reclaimed wastewater main installations, regardless of piping material, shall also include the

installation of a utility identifier warning tape buried directly over the pipe twelve (12") inches below the ground surface continuously. The tape shall be at least two (2") inches wide, be purple on top, and be boldly labeled every eighteen (18") to thirty-two (32") inches as follows �CAUTION RECLAIMED WASTEWATER LINE BURIED BELOW�. The tape shall have a tensile strength of no less than 4000 psi, a dart impact strength of no less than 120grams per 1.5 mils, and be no less than 0.0055 inch thick. The tape shall be designed to last as long as the pipe it is installed over, even in adverse soils.

3. All water main installations, regardless of piping material, shall also include the installation of a locator

wire. The locator wire shall be installed in the same ditch and as close as possible to all water mains in a continuous fashion and terminating in the valve boxes and/or blow-off boxes. The wire shall be looped in the valve boxes and/or blow-off boxes to allow for the convenient connection of an electronic locator transmitter at intervals of not greater than every one thousand (1000') feet along the length of the water main. If a valve box is not available to provide this interval, the wire shall be looped into a “dummy” cast-iron valve box set at grade level. Locator wire shall be stranded 12-gauge copper with insulation rated UF or USE by Underwriter’s Laboratories. Underground splice connections shall be minimized and shall be rated for direct burial service. Prior to acceptance of the water main, the Contractor shall conduct a continuity check of the tracer wire, to verify that the wire has not been broken during installation.

8.1.4 Dead Ends: Dead ends shall be minimized by the looping of all mains whenever practical. Where dead

end mains occur they shall be provided with a blow-off for flushing purposes. No flushing device shall be directly connected to any gravity wastewater line.

SECTION 8.2 - VALVES AND VALVE BOXES 8.2.1 Isolation Valves: Sufficient isolation valves shall be provided on reclaimed wastewater mains so that

inconvenience and sanitary hazards will be minimized during repairs. Valve location requirements are: 1. Two valves at the point where one main ties to another. 2. Three valves where two mains cross. 3. Four valves at major distribution points.

Valves should be located at not more than 500-foot intervals in commercial districts and at not more that one block (or 800 foot intervals) in other districts. All valves shall open to the left (i.e., counter-clock-wise) and shall comply in all respects with the requirements in Section 4.1.6 of this document unless approved otherwise by the MPW Engineering Dept.

8.2.2 Air Release Valves and Blow-off Assemblies: 1. Air Relief Valves: At high points in reclaimed wastewater mains, where air can accumulate, provisions

shall be made to remove the air by means of air relief valves.

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2. Blow-Off Valves: Blow-off valves may be installed on dead end lines and low points in a transmission

line for purposes of removing silt and debris from the distribution system. No blow-offs shall be directly connected to any wastewater line. A square lockable lid cover marked “Reclaimed Wastewater Valve” shall identify blow-offs. The lid shall be painted red. All fittings, valves, and pipe inside the service box shall be painted purple.

3. Chamber Drainage: Chambers, pits or manholes containing valves, blow-offs, meters or other such

appurtenances for a reclaimed wastewater distribution system, shall not be connected directly to any storm drainage or sanitary wastewater line, nor shall blow-offs or air relief valves be connected directly to any wastewater line.

8.2.3 Valve Boxes: Reclaimed wastewater valve box covers shall be square and painted purple. Valve box

covers shall be marked "Reclaimed Wastewater" ) and shall comply in all respects with the requirements in Section 4.1.6 of this document.

SECTION 8.3 - SERVICE CONNECTIONS 8.3.1 Service Lines: Service lines shall be as required by the property served, but shall in no case be less

than one (1") inch in diameter. All other sized service lines are subject to the approval of MPW. 8.3.2 Service Connections: A service box shall be located at the property line and contain a lockable curb

stop or isolation valve and meter. The lid, fittings, valves, meters and other items contained in the service box shall be painted purple.

8.3.3 Customer Responsibilities: MPW and SCDHEC must approve other reuse applications of effluent

aside from irrigation. Customers who use reclaimed wastewater shall be responsible for all uses or misuses on their premises. Each customer shall install and maintain suitable devices to ensure that no reclaimed wastewater is injected into any aquifer, including shallow aquifers, or is allowed to flow into surface water, including, but not limited to lagoons, creeks, drainage ditches, drainage pipes, tidal creeks. Dikes, berms, etc. may be required to contain runoff.

8.3.4 Prohibitions and Limitations: No connection between the reclaimed wastewater system and the

potable water system shall be allowed. Irrigation systems using reclaimed wastewater shall not be connected to any potable water system or well that is used for drinking, food preparation, clothes washing or for any other purpose that normally calls for potable water.

SECTION 8.4 - DEDICATED SPRAY IRRIGATION SITES 8.4.1 Application Rates: The design effluent application shall not exceed two (2") inches per week. In

general, golf course irrigation shall occur during nighttime hours, and irrigation of other dedicated sites shall occur during daylight hours.

8.4.2 Storage: A lined pond is required for the storage of treated effluent when land application cannot be

properly carried out due to reduced loading rates (e.g., prolonged rain) or complete system shutdown. Storage requirements should be based on a water balance computation, taking into consideration the evapotranspiration, soil percolation, and precipitation rates. The minimum storage pond capacity will be as computed or seven days average daily design flow, whichever is greater. All storage ponds must be permitted and approved by SCDHEC. This will include, but is not limited to the installation of an impermeable liner.

8.4.3 Golf Courses:

1. Spraying: Spraying of effluent shall be restricted to designated greens, tees, and fairways. Buffer zones

will be maximized with a minimum distance of 75 feet between spray impact area and residences. 2. Mixing Ponds: Golf courses normally have to supplement the effluent with either storm water, potable

water or both. Consequently, a mixing or blending pond should be provided, since dual irrigation systems are not usually feasible and cross-connections are not allowed. If the mixing pond has three sources of

42

water (storm water retention ponds, effluent storage ponds, and the potable water system) the potable water inlet should be placed above the top elevation of the mixing pond dike, so there is an air gap to prevent the possibility of a cross-connection. The storm water retention pond would have two outlets, one to surface waters and one to the mixing pond. The effluent storage pond and the storm water retention pond inlets to the mixing pond should be designed to prevent effluent discharges to surface waters through the storm water system. The mixing pond must be permitted and approved by SCDHEC and should not be used as a golf course water hazard.

43

CHAPTER 9 ASPHALT PAVEMENT

Topics covered in this chapter include: ! Applicable standards ! Materials ! Execution ! Guarantee SECTION 9.1 - APPLICABLE STANDARDS All construction, repair, and resurfacing of asphalt pavement shall be conducted in accordance with the South Carolina Department of Transportation (SCDOT) Standard Specification for Highway Construction and the American Society for Testing Materials (ASTM):

D-698 Test for Moisture-Density Relations for Soils D-1557 Test for Moisture-Density Relations for Soils

SECTION 9.2 - MATERIALS 1. Provide fossilized limestone base course (with prime) in accordance with Section 306, Type 2, of the

SCDOT Standard Specifications, latest edition, with the following exception: Less than 8% of the material shall be permitted to pass the #200 sieve. Compact base course to 100% of the maximum dry density when tested in accordance with ASTM D1557, Method D (Modified Proctor Density).

2. Provide 0.20-gallons/sq. yd. of bituminous prime material meeting the requirements of RC-250 Cutback

Asphalt (Rapid Cure) AASHO M81. 3. Provide Type I hot laid asphalted concrete surface course in accordance with Section 403 of the SCDOT

Standard Specifications. Compaction shall be required to be at least 97% of the laboratory density as determined by the 50 blow Marshall mix design method (ASTM D 1559).

SECTION 9.3 - EXECUTION 1. Apply bituminous prime coat in accordance with Section 406 of the SCDOT Standard Specifications.

Bituminous prime coat shall only be applied when the air temperature in the shade is above 60 degrees Fahrenheit. Bituminous material shall be applied to the full width of the area to be paved. The Contractor shall protect all structures and concrete surfaces from the bituminous material.

2. Apply asphalted concrete surface course in accordance with Section 403 of the SCDOT Standard

Specifications. The asphalted concrete surface course shall be laid using a mechanical spreader when possible. The pavement shall be constructed on the previously completed and approved surface or base. Rolling of placed material shall begin immediately. The air temperature when placing the when placing the asphalted mixture shall be not less than 60 degrees Fahrenheit and rising. The Contractor shall supply copies of all pavement material invoices indicating conformance with specifications to the Engineer upon request.

3. Pavement replacement shall extend a minimum of one foot beyond the trench line, and shall include

replacement of all defective pavements resulting from the Contractor’s operations, regardless of whether caused by blasting, trenching, equipment operation, cave-in or other cause. Where the cut edge of pavement is less than one foot from the edge of the trench, or has been disturbed during construction, the Contractor shall cut through and remove existing pavement as required to permit a neat pavement patch. Irregular or uneven patches will not be permitted. Prior to replacing pavement, the inside edges of the existing asphalt shall be coated with a thin application of liquid bituminous material.

SECTION 9.4 - GUARANTEE The Developer and Contractor shall guarantee all pavement work and pavement repair work completed incidental

44

to the installation of the wastewater lines for a period of two (2) years following acceptance by MPW, and shall repair or replace, at no cost to MPW, any pavement or pavement repair, which crumbles, cracks, or is otherwise unsound during this two year period. Warranty period does not go into effect until roadways have been inspected and approved by Town, County, or State Highway Departments. If asphalt work involves county or state encroachment permits, it is the contractor and developers responsibility to assure that all permit requirements have been met.