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HomeMy WebLinkAboutWWP2703356.3ca 0 cri 0 z rn O O r- O rn i- W W % "Z o n. aU) ONCL ON Di N 0 Onri 0 /d OQ N [L O\_= ?\<.Q CL d- (Oa. ni WWW� 7-MMQ ZF-F-Z �ix Ev)ii� 0 PART TWO - MATERIALS 2-1 GENERAL All materials and equipment shall be new and workmanship and materials shall be good quality. All material incorporated into `the work shall conform to the provisions of this part. All references to Specifications shall be of the latest edition. 2-2 MATERIAL LISTS AND SPECIFICATIONS The Developer or his Contractor shall deliver to the Engineer a material list not less than ten (10) days before commencement of construction. The list shall contain the manufacturer and model number, if applicable, of the material and equipment to be installed as a part of the work so that the Engineer may determine whether such materials conform to the Plans and Specifications. No materials that are not included in the material list shall be installed as a part of the work. The manufacturer's technical specifications _ for pipe, appurtenances and equipment to be incorporated into the work shall be submitted to the Engineer at least ten (10) days prior to commencement of construction with the materials listed. 2-3 GUARANTEE BY MANUFACTURER If requested by the District or by the Engineer, a written guarantee made by the manufacturer of any materials to be incorporated into the work shall be furnished, guaranteeing to the District that such materials shall conform to these Specifications and any specifications otherwise applying to the work. 2-4 SEWER PIPE AND APPURTENANCES, NON -PRESSURE Non -pressure sewer pipe shall be PVC pipe conforming to ASTM D-3034 for depths of cover between 5 feet to 12 feet; and Ductile Iron pipe, class 50, cement lined conforming to AWWA Standard C-151 and C-104 for depths of cover less than 5 feet or exceeding 12 feet and for slopes less than 1% and and over 15%. Pipes installed at slopes 15% or greater shall incorporate "Field Lok" gaskets for the entire run. PVC sewer pipe is defined as flexible conduit. Joints shall conform to ASTM D-3212 using a restrained rubber gasket conforming to ASTM F-477. Fittings shall be injection molded tees or factory solvent welded saddle tees. Saddles fastened to pipe with external bands are not acceptable on any new system. Ductile Iron pipe is defined as rigid conduit. Mechanical or push -on joints shall conform to AWWA Standard C-110. 2-5 SEWER PIPE AND APPURTENANCES PRESSURE Unless otherwise specified, pressure pipe shall be constructed of: (a) Ductile Iron pipe conforming to AWWA C-151 with a manufacturer's thin cement lining conforming to AWWA C-104 (except as to thickness) and with the type of joint, class, thickness, designation and markings as specified. (b) Cast Iron fittings shall be rubber -gasket and shall conform to AWWA C-110 and C-111. Valves shall conform to AWWA Specifications C-500. 2-6 MANHOLES - 54" STANDARD (a) Manhole Frames and Covers Cast Iron frames and covers shall conform to the Olympic Foundry Company No. MH30A, or equivalent. Castings shall conform to the requirements of ASTM A48, class 30 and shall be free of porosity, shrink cavities, cold shuts, or cracks or any surface defects which would impair service ability. Repair of defects by welding, or by the use of "smooth -on" or similar material will not be permitted. Cover to be non-skid type surface and shall have the word "SEWER" in large raised letters. A bituminous coating shall be applied to all surfaces. The finished coating shall be continuous, smooth, neither brittle when cold nor sticky when exposed to the sun, and shall be strongly adherent to the casting. The District shall have the right to require inspection and approval of all castings prior to painting. Manhole rings and covers shall be machine finished or ground on seating surfaces to assure non -rocking fit in any position, and interchangeability. At the request of the District, there shall be made available at the foundry standard rings and standard covers for use by inspectors in testing fit and seating. Manholes located outside public rights -of -way shall be equipped with a locking device of such design that the cover may be readily released from the ring. All movable parts shall be made of non -corrosive metals otherwise arranged to avoid possible binding. At the request of the District, there shall be made available at the foundry a testing device suitable for proving the capacity of the of the assembly to resist an uplift pressure on the lid equal to a 20-foot head. The locking frame and cover shall be Metro standard frame and cover with 3-screw-type locking lids. All manhole frames and covers shall be identified by the name or symbol of the manufacturer. This identification shall be in a plainly visible location when the frames and covers are installed. In addition to the manufacturer's identification, the material shall be identified by the following "NOD" or "DUC" for nodular or ductile iron respectively. The manufacturer's identification and the material identification shall be adjacent to each other and shall be minimum 1/2-inch letters, recessed to be flush with the adjacent surfaces. (b) Precast Manhole Components Precast manhole components shall conform to ASTM C-478 except as modified herein. Base section openings to receive pipe shall be circular, tapered inward, and held to the minimum size practical to aecomodate the pipe to be inserted to effectively seal the joint. Pipe to manhole connections shall be made with a rubber boot installed in a pre -cored opening. DESIGNED PH DRAWN JMU CHECKED DBH ISYM Precast manhole elements shall be provided with steps and/or ladders such that the completed manhole will contain a continuous vertical ladder with rungs equally spaced at 12 inches apart plus or minus 3/4 inch. The lowest rung shall be not more than 16 inches above the shelf, and the uppermost rung shall be not more than 18 inches below the street surface. Joints between precast manhole elements shall be rubber gasketed similarly to pipe joints and shall conform to ASTM C-433. Shop drawings of the joint design shall be submitted to the 'Engineer for approval, prior to manufacture. Completed joints shall show no visible leakage and shall conform to the dimensional requirements of ASTM C-478. Standard flat slab covers for shallow manholes shall be a minimum of 8 inches thick and shall conform to the outer dimension of the standard sections upon which they are to be placed. The 24-inch diameter opening shall be eccentrically located as shown on the Standard Plans to provide at least 6 inches minimum radial distance from the edge of the 24-inch opening to the inside face of the standard section below. Reinforcing shall be as shown on the Standard Plans. Reduction to 24 inches shall be made by means of of a flat slab, for shallow manholes, or an eccentric precast cone for standard manholes. (c) Deformed Bar Steps Galvanized deformed bar steps shall be 1-inch-diameter deformed bar conforming to ASTM A-615, Grade 40 or Grade 60, hot bent and galvanized after bending. For Bending, the temperature shall be at least 1,600 degrees F. Galvanizing shall conform to ASTM A-123. Step dimensions and pattern shall conform to the Standard Plans. Polypropylene coated steps shall conform to ASTM C-478 with deformed bar conforming to ASTM A-615. Steps shall be Lane model P-14938 or approved equal. (d) Ladders Precast manhole base sections more than three feet in height shall be provided with a ladder as detailed on the Standard Plans. Ladders shall be galvanized steel or polypropylene coated. 2-7 IMPORTED BACKFILL MATERIAL Imported backfill material shall be free from wood, bark, roots or other extraneous material and shall meet the following requirements: U.S. Standard % Passing Sieve Size I By Weight 2-112" Square Opening 100 1/4 Sieve 25 Min. No. 200 10 Max. Sand Equivalent 35 Min, PEA GRAVEL WILL NOT BE ALLOWED AS BACKFILL MATERIAL. 2-8 TRENCH FOUNDATION MATERIAL Over -excavated material shall be replaced with trench foundation material conforming to one of the following gradations as specified: U.S. Standard Class "A" Class "B" Sieve Size Min. Max. Min. Max. 2-1/2" square opening 98% 100% 95% 100% 2" square opening 92 100 75 100 1-1/2" square opening 72 87 30 60 1-1/4" square opening 58 75 0 15 3/4" square opening 27 47 0 1 3/8" square opening 3 14 0 0 No. 4 sieve 0 1 0 0 2-9 BEDDING MATERIAL Bedding material shall be well -graded, clean, granular material, commonly known as pea gravel and shall meet the following requirements: U.S. Standard % Passing Sieve Size By Weight Pea Gravel: 3/8" square opening 100 #8 sieve 0-5 2-10 ASPHALTIC CONCRETE Asphalt concrete pavement shall conform to the technical requirements for Class B Asphalt in the latest edition of the State of Washington Standard Specifications for Road, Bridge and Municipal Construction. 2-il TOP COURSE AND KEYSTONE MATERIAL For use in the restoration of excavated areas, Top Course and Keystone material shall be manufactured from ledge or talus rock, be free from woo roots, bark and other extraneous material and shall conform to the folio requirements: U.S. Standard % Passing Sieve Size y Weight 5/8" square opening 100 1/4" square opening 55-75 U.S. No. 40 sieve 8-24 U.S. No. 200 sieve 10 Max. Sand Equivalent 40 Min. 2-12 BASE COURSE MATERIAL Base course material shall conform to the following requirements: U.S. Standard % Passing Sieve Size By Weight 1-1/2" square opening 100 5/8" square opening 50-80 1/4" square opening 30-50 U.S. No. 40 sieve 3-18 U.S. No. 200 sieve 7.6 Max. Sand Equivalent 40 Min. •� ���� pii6E, REVISION DATE BJ An Engineering Services Company 2-13 wing CONCRETE BEDDING AND BLOCKING 3-9 PIPELAYING Compaction of backfill shall be achieved by power operated tampers, roller 3-17 TESTING OF PRESSURE SEWER PIPE vibration equipment or other mechanical means. Water settling will not be Bedding and blocking concrete shall be Portland cement concrete containing Each pipe shall be laid with bells upgrade and the invert of the pipe to the acceptable as a means of compaction. If excavated material has a California All force mains shall be tested at a minimum pressure of at least 50 percent four sacks of cement per cubic yard and maximum aggregate size of 1-1/2 alignment and grade shown on the Plans. Concentric joints shall be closed Bearing Ratio for compacted and soaked sample of less than 7, or for any above the design operating pressure for at least 30 minutes. Leakage shall inches. Maximum slump shall be 3-1/2 inches. and a smooth invert provided. Open ends of. pipes or fittings shall be other reason cannot be compacted as specified, such excavated material shall not exceed the amount given by the following formula: temporarily blocked or covered when laying is not in progress. be replaced with imported backfill material. No backfill shall be placed N D./T PART THREE -CONSTRUCTION without immediate compaction according to these specifications. L= 1850 Adjustment to the line and grade shall be done by scraping away or filling 3-1 GENERAL and tamping bedding material under the body of the pipe. No wedging or The District will require that the services of an independent testing laboratory Where: L = allowable leakage in gallons per hour blocking of the pipe for adjustment to line and grade may be done. or county testing laboratory be employed to perform in -place density tests to N = the number of pipe joints Except as otherwise noted herein, all work shall be accomplished as recommended ascertain whether the specified density can be or has been obtained. The D = the pipe diameter in inches in the latest revision of AWWA and APWA Specifications and according to the The pipe shall be lowered into the trench by means of ropes, tripod, crane or costs of these tests shall be borne by the Developer. P = the test pressure in psi recommendations of the manufacturer of the material and equipment concerned. any other suitable means, shall not be dropped or handled roughly, and shall All specified depths shall be compacted depths. be checked for cracks and defects before installation. Any cracked or Regardless of the approval of the District as to the manner of compaction or 3-18 6-INCH SIDE SEWER FROM MAIN TO PROPERTY LINE defective pipe shall not be installed. testing, the Developer shall repair any settlement of trenches and excavations In roadway areas, all asphalt and concrete pavement shall be saw cut. When that may occur within two years after completion and formal acceptance of the The material and strength class of side sewer pipe shall be the same as the trenching operations cut through concrete pavement, the pavement shall be Tees, wyes and standing services shall be installed as shown in the Standard work by the District. sewer pipe to which it connects and these specifications shall be applicable removed to a width of 18 inches eater than the top width of the trench. The Details herein and at such locations as shown on the Plans, or as otherwise to side sewer work. The slope of side sewers shall not exceed 2-foot vertical concrete shall be saw cut on a straight line and shall be beveled so that the cut _ _ directed by the District. They shall not be covered until the District has 3 14 CLEANING AND FLUSHING o I - foot o ' o tal and a e shall not be less than 2 ercent. Side sewers gr p t 1 f of h riz n d will be approximately 1 inch wider at the top than at the bottom. Asphalt paving completed inspection and recorded their exact location. " shall have minimum 48 cover. When change in slope exceeds 2 inches per foot, shall be saw cut ahead of the backhoe to prevent excessive tearing up of the Prior to pipe testing, all pipes shall be cleaned as provided in this section. standard wye bends shall be used. All side sewers shall be plugged and the surfacing and to eliminate ragged edges. Variance from established line and grade shall not be greater than 1/32nd of An inflatable ball of a size that will inflate to fit snugly into the pipe shall be plugs blocked. an inch per, inch of pipe diameter, but shall not exceed 1/2 inch or result in furnished by the Contractor and placed in the last manhole on the pipe to be 3-2 TRENCH EXCAVATION a level or reverse sloping invert. cleaned. The ball may be used with a tag line or a rope may be fastened to The ends of all side sewers at the property lines shall be marked with a the ball to locate and control its position at all times. Water shall be 2" x 4" board, the bottom of which shall be located at the invert of Trenches shall be excavated to the line and grade designated by the District. 3-10 PIPE JOINTS introduced behind the ball and the ball shall pass through the pipe with only the end of the side sewer and the top of which shall be painted °green and Unless otherwise specified, trench sides shall be excavated vertically. Trench the force of the water impelling it. All debris flushed ahead of the ball shall extended 4 feet above the ground with the length of the board and labeled widths shall be adequate for proper working space and placement of bedding No joints shall be covered until examined and approved by the District. Only be removed at the first manhole where presence of the debris is noted. In the "SEWER" in 2" high white stenciled letters. The entire length of the board shall material under and around the pipe. The trench width, from the bottom of the pipelayers experienced with the type of gasket being used in the work shall event that cemented or wedged debris or damaged pipe shall stop the ball, the be wrapped with a heavy gauge wire which is attached to the spigot end of the trench to 4" above the crown of the pipe, shall not exceed 40 inches for 15- be allowed to lay pipe. On the request of the District, proof of such obstruction shall be removed. pipe. inch diameter and smaller pipe, or 1.5 times the inside diameter of 1.8-inch experience shall be funished before laying may begin. or larger pipe, plus 18 inches. If these widths are exceeded, a stronger grade of pipe and/or a higher classification and amount of bedding material shall be Joint material shall be installed according to the manufacturer's 3-15 TESTING OF NON -PRESSURE SEWER PIPE -DEFLECTION 3-19 CONNECTION TO THE EXISTING SYSTEM furnished, as directed by the District. recommendations. After the gasket has been affixed, the pipe shall be TESTING FOR FLEXIBLE SEWER PIPE No connections shall be made to the existing sewer system without the handled to ,avoid bumping the gasket, knocking out of position or loading it All non -pressure sewer pipe shall be air tested. The procedures set forth in presence of the District. Written application for connection shall be made to Excavation for manholes or other structures shall be sufficient to provide a with dirt or other foreign material. Any gasket so disturbed shall be removed, this section shall be employed in conducting the testing. All facilities and the District for connection, and the connection shall be made at a time agreed minimum of 18 inches between the structure and the sides of the excavation, replaced, cleaned and relubricated before the joint is made. The pipe shall be personnel for conducting the testing under the observation of the District shall upon with the District. enough to allow for proper compaction of the surrounding backfill. properly aligned before the .joint is forced home. During insertion of the be furnished by the Developer. All equipment and personnel to conduct the tounge or spigot, the pipe shall be partially supported by hand, sling or crane test shall be subject to the approval of the District. Although air testing may Connections to existing manholes shall be made as follows: If the manhole is "live, be tightly to breaking into All material excavated from trenches and piled next to the trench, shall be as required to minimize lateral pressure on the gasket and to maintain be performed for the convenience of the Contractor before backfillin , no manhole channel shall covered, prior placed and maintained so that the top of the material is at least 2 feet from concentricit;f until the gasket is properly positioned. Pipe deflection and pipe shall be accepted until air tests have been performed after bacillin and P P g the manhole wall, to prevent debris from entering the sewer line. the edge of the trench. Excavated material shall be located so that free access straightening shall be avoided once the joint is home, to prevent creep of the compacting. immediately after the connection is made, the new pipe shall be plugged. is provided to all fire hydrants, water valves, meters and other utilities, and joint. The plug shall not be removed without permission of the District. If the clearance shall be left to enable free flow of storm water in all gutters, conduits and natural water courses. Sufficient pressure shall be applied in making the joint to assure that the joint All es, tees and ends of side sewer stubs shall be plugged with flexible �' P gg existing manhole is not "live," a plug shall be installed in the downstream or discharge pipe of the existing manhole in addition to the above. is home, as defined in the pipe manufacturers standard instructions for joint caps, or an alternate acceptable to the District, and securely fastened to 3-3 TIMBERING AND SHEETING installation. Sufficient restraint shall be applied to the line to assure the withstand the internal test pressure: Such plugs or caps shall be readily removable and their removal shall provide a socket suitable for making a Connections of new mains to existing sewer lines shall be made as follows: The developer shall provide and install timbering and sheeting as necessary joints, once home, are held so by tamping .fill under and alongside the pipe or other appropriate means. At the end of the day's work, the last pipe laid flexible -jointed lateral connection or extension. No double plugs shall be Anew manhole shall be placed over the existing line. The manhole shall be precast 54-inch diameter except that the base slab shall be cast in place. The to protect workers, the work, existing buildings, utilities and other properties, shall be blocked in such a manner as may be required to prevent creep during used. new connection shall be plugged and blocked and the existing sewer pipe and shall meet all OSHA and WISHA requirements. downtime. Immediate) following the pipe cleaning, y g p'p anng, and manhole channeling the pipe shall not be opened without the permission of the District. 3-4 JACKED OR BORED CROSSING 3-11 MANHOLIES installed shall be tested with low pressure air. Air shall be slowly supplied Connections of side sewers to an existing sewer line shall be made as follows, to the plugged pipe installation until the internal air pressure reaches 4.0 or as directed by the District Engineer,. All work shall be done in conformance with the requirements of the agency Precast manhole base sections shall be placed on a well -compacted bedding The the bedding be less than Pounds per square inch greater than the average back pressure of any ground water that may submerge the pipe. At least two minutes shall be allowed A) For ductile iron the be made a stainless in control of the facility being bored or jacked. See Roadway and Railway course of bedding material. depth of shall not for temperature stabilization before future procedure. A pressure gauge with pipe, connection. shall with Crossings for further details. 4 inches thick, extending a minimum of 12 inches beyond the outside perimeter of the base section. The balance of any remaining excavated area a maximum of 30 p.s.i. shall be used for testing. steel, or stainless steel with ductile iron flange,. tapping tee, Romac model "SST" or equal, A FL by MJ adapter is required. 3-5 ROADWAY AND RAILWAY CROSSINGS shall be filled with imported backfill material and well tamped to the level of the top of the bedding before the manhole is set in place. The bedding shall The pipe shall be acceptable if the time required in seconds for the pressure B) For PVC or AC pipe, the connection shall be made with a sewer Any method may be used for roadway or railway crossings that provides for be well tamped and made smooth and level to assure uniform contact supportn to decrease from 3.5 to 3.0 psi greater than the average back .pressure is equal to or greater than the listed values for corresponding sizes of pipe shown of saddle Romac style " " I , ye CB or equal. satisfactory results and is acceptable to both the District and the governmental or private agency having control of the road or track, provided that the road to the precast elements. the air test graph Located elsewhere in Part Four. Hazards created by use of The existing sewer pipe shall be cut or drilled to ive-a smooths symmetrical g P P g or track shall be restored to its original condition after the crossing is All lift holes and the inside and outside face of rubber gasketed joints air pressure for testing pipe shall be guarded against, and all plugs shall be securely blocked to prevent blowouts. A supply air regulator shall be opening of the proper size. Each connection shall be bedded with a 4-inch completed. If tunneling or jacking is elected or required for crossings, steel, p hng j g ' q g cast iron or concrete pipe casing shall be placed and the sewer pipe laid between precast .sections shall be thoroughly wetted, pointed, .then filled with mortar, and smoothed both inside and out. Precast sections shall be placed installed on the air supply to the sewer that will allow only a maximum thick concrete pad in place to the lower quadrant of the pipe barrel. Unsuitable foundation material shall be overexcavated and replaced with within the casing. For District Standards for boring or tunneling see "Water and aligned to provide vertical sides and vertical alignment of ladder rungs. of 6 psig in the line to be tested and. all pressure shall be relieved from the sewer line before removal of test plugs. bedding material. or Sewer Casing Detail on seperate sheet. The completed manhole shall be rigid, true to dimension and watertight. 3-6 TRENCH FOUNDATION Manholes set in paved streets or other paved areas shall be set to the finished When required b the Engineer, all sari sewers constructed of flexible 3-20 q y TRAFFIC CONTROL grade of the paving. When required, the manhole frame shall be tilted to pipe shall be deflection tested not less than 30 days after the trench backfill All traffic control shall be per the Manual of Uniform Traffic Control Devices, If, in the judgement of the District, the native trench bottoms will provide a conform to the grade of the paved surface. Manholes not set in paved areas 1p P P and compaction has been completed. The test shall be conducted by pulling a solid pointed mandrel with diameter equal to 95 percent of the pipe and/or agency of jurisdiction. During construction, traffic shall not be delayed / g y j g Y firm base for the subsequent placement of bedding, pipe and backfill, such shall be set at a finished grade slightlyhi her than that of the surrounding �' g � terrain to prevent surface water infiltration into the system. Manholes set p yst diameter through the completed .pipeline. Testing shall be conducted on a a for more than 5 minutes unless previously approved b the District and the P y PP y agency of jurisdiction. ag Y native trench bottom may be used if the bottom is leveled and smoothed so that the entire length of pipe will rest on a well -compacted base. Trench in unpaved areas shall have an asphalt pad, 2" thick and 6' in diameter manhole -to -manhole basis and shall be done after the line has been bottoms shall be over -excavated as necessary to remove all unstable soil and laced around the manhole casting. Manholes at the end of a line with no P g completely flushed out with water. The Contractor will be required, at his 3-21 expense, to locate and repair any sections failing to passs the test and to T.V. INSPECTION " "quick" eliminate "boiling or quick conditions to such a depth as to provide a firm inflow, shall have sloped floors to drain to the outflow. If there is inflow, p retest the section base. Over -excavated materials shall be replaced with trench foundation a channel shall be provided. Unless needed to clear a paved road, stub- Prior to acceptance, all pipe shall be flushed at the contractors expense and material as specified in Section 2-8. Foundation material shall be placed outs and channels intended to faciliate future hookup shall be omitted. T.V. inspected by the District at contractors expense. Contractor shall notify when ordered by the District. - 3 16 MANHOLE ACCEPTANCE TESTS the District 48 hours pior to the need for flushing and T.V. inspection. All Manhole channels shall be made to conform to the sewer grade and shall be manholes must be channeled, the sewer system completed and the roadway 3-7 BEDDING MATERIAL PLACEMENT brought together with well-rounded junctions. Channel sides shall be carried All manholes shall be subject to an acceptance test at the request of the subbase (ATB or 2" class B asphalt) installed before the T.V. inspection. vertically to the crown elevation of the various pipes. The concrete shelf Owner. Manholes shall be tested by an approved vacuum test. Sewer dye, Norlab or approved equal, shall be introduced into the system prior All flexible pie shall be placed in bedding material of the type specified in shall be smoothly finished with slopes to drain. Channels shall not narrow to the T.V. inspection, if required. The T.V. camera must be pulled through Section 2-9 (a). The bedding shall be placed from a minimum of 4 inches down to less than the inside diameter of the pipe, Water testing of the manholes shall not be allowed. the pipe without use of a hydraulic flushing nozzle. VHS video tape of this below the pipe barren to 4 inches above the pipe as shown on the inspection shall be submitted to the District along with a completed certified Standard Detail herein. Bedding material shall be worked by hand under, around All pipe openings, when practical, shall be cored before setting the manhole. The vacuum test shall be performed prior to the installation of the manhole report by the Contractor. Video must start at the downstream manhole and and over the pipe to the depths required for the full width of the trench. Pipe connections shall be made by use of a rubber boot connector, Kor N channeling. proceed upstream against the flow. All defects revealed by the T.V. inspection Seal or equal. shall be repaired by the Contractor to the Districts satisfaction. Any pipe or All rigid pipe shall be placed in bedding material of the type specified in All lift holes shall be plugged and seams sealed. All pipes entering the sanitary manhole channel with a sag that creates a standing water depth of 1/4-inch may be rejected by the District (No sag of 1/2-inch or greater will Section 2-9 (a) or (b). The bedding shall be placed from a minimum+ of 4 3-11: BACKFILhING manhole shall be temporarily plugged, taking care to securely brace the be accepted.) Depending on the severity and extent of the defects, the inches below the pipe barrel to the spring line of the pipe as shown on the pipes and plugs to prevent them from being drawn into the manhole. District may require that the entire pipe run be relayed. Standard Detail. Bedding shall be placed in more than one lift. The first lift, No backfilling shall be performed until after the District has inspected the to provide at least 4-inch thickness under any portion of the pipe, shall be installation of the pipe and bedding and approved backfilling. The test head shall be placed at the top of the manhole in accordance to placed before the pipe is installed and shall be spread smoothly so that the the manufacturer's recommendations. A vacuum of 10 inches of mercury 3-22 SIDE SEWERS pipe is uniformly supported along the barrel. Subsequent lifts of not more than 6-inch thickness shall be placed as shown on the Standard Detail and The initial backfill shall be hand placed select material spread evenly over the bedding material and compacted by hand to an elevation of 6 inches above shall be drawn on the manhole, the valve on the vacuum line of the test head closed, and the vacuum pump shut off. The time shall be measured A side sewer permit will be required from the District before installation of individually compacted to a minimum of 90 percent of maximum density. the crown of the pipe for Ductile Iron vie and 10 inches above the crown for the vacuum to dropto 9 inches of mercury. The manhole shall ass if side sewers. Commercial waste discharge from fixtures and equipment that d, Shoring to be removed,. or moveable trench shields or boxes, shall be located of the Rive for PVC. This shall be done in such a manner that subsequent the time A takes the ere to dropfrom 10 inches of mere to 9 may contain grease, including but not limited to, scullery sinks, -pot and pan at least 2-1/2 pipe diameters away from flexible pipe if the bottom of the baefillin will not disturb the pipe in an way. Subsequent lifts of not more g P P y y q inches of mercury meets or exceeds the values indicated in Table l below, sinks, dishwashers, soup kettles, and floor drains located in areas where shoring, shield or box extends below the to of the pipe, unless a satisfactory g P P�P i'3' than 2-foot thickness shall be placed as shown on the Standard Details and ease containing materials may exist, will require a grease interceptor prior �' g y q g P means of reconsolidating the bedding or side support material disturbed by individually compacted to a minimum of 90 percent maximum density. TABLE 1 to entering the sanitary sewer system. Commercial establishments that may shorin removal can be demonstrated discharge oil into the sanitary sewer system will require an oil separator prior g Subsequent backfilling shall be performed by pushing material from the end In solid rock excavation, all ledge rock, boulders or stones shall be removed of the trench along and directly over the pipe so that the material will be g applied in a. rolling slope, rather than by side filling. Backfilling from the to provide a minimum clearance of 8 inches under the pipe. All material thus sides of the trench will not be done until the District has determined that removed shall be replaced with bedding material. material has been carefully placed over the pipe to a sufficient depth. 3-8 GRADE LINES In areas such as existing paving, or in areas to be paved, where the District determines that minor settlement would be detrimental and the native excavated The Contractor shall maintain the correct grades between manholes and shall_ material is :not suitable for compaction as backfill, the trench shall be backfilled check all intermediate grade stakes by means of a taut grade wire between at with imported backfill material as specified in Section 2-7. least three intermediate grade stakes. In the event that the grade stakes do not line up, the work shall be stopped until the situation is corrected. All bench 3-13 COMPACT:[ON OF BACKFILL marks, reference points and stakes shall be preserved. In case of destruction of any of them, the resulting expense of restoration shall be borne by the Compaction of backfill and backfill procedures in public rights -of -way shall, Developer. Construction staking shall consist of grade stakes at 10 foot at the minimum, conform to the requirements of the governmental agency UN B . offsets. Stakes at each manhole and intermediate grade stakes shall be offset having jurisdiction thereof. e�;�� w,4sk ��' nF 10 feet and located at 50 foot stations between manholes. Laser beam equipment for grade and alignment control is an acceptable alternative. Bacldilling shhall be compacted to 95 percent of maximum theoretical density �� ti� c�- 11255 Kirkland Way, Suite 300 Kirkland, WA 98033 p. 425.827.2014 1 f. 425.827.5043 &I1 i Structurai Pianning, Survey in all areas where paving will be placed over the backfill or in shoulder areas and to 90 Dercent of maximum theoretical density in al. other areas, Measurement. of compaction density shall be by the modified AASHTO method. •,_.' --. tom..COAL CREEK UTILITY DISTRICT DATE MAY 2007 SCALE NO SCALE Depth (feet) Manhole Diameter inches 48 54 60 66 72 Time (seconds) 8 20 45 26 29 80 10 25 45 33 36 80 12 30 45 39 43 80 14 35 45 45 51 80 16 40 60 52 58 120 18 45 60 59 65 120 20 50 60 65 72 120 to entering the sewer system. 3-23 STREAMGUARD CATCH BASIN INSERTS All catch basins located along project shall have a streamguard sediment catch basin insert model 9226 as manufactured by Ultra -Drain Guard, model 3003 as manufactured by Foss Environmental or approved equal installed. Inserts are to be cleaned and replaced by Contractor per manufacturer's recommendations or by District direction. S•335603 LU SHORT PLAT SEWER EXTENSION NOTES �, I<, EXPn2Es 07/07/6-1 02 01 ts' �ss4"(WA . j ' I EXPUM 03/04/ JOB NUMBER 07009.00 SHEET NAME NOTES SHEET 3 OF 3 Q0'.-)-5»bVD - --- ----•- L• - ---