D. Removal of existing storm sewerage pipe and drainage structures.

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1 SECTION PART 1 - GENERAL 1.01 RELATED DOCUMENTS A. Drawings and General Provisions of the Contract, including General and Supplemental Conditions, Division B and other Division 1 Specifications Sections, apply to this Section WORK INCLUDED A. Storm Sewerage System, including all manholes, pipe, bedding, fittings, connections to existing facilities, system accessories and construction of Infiltration Areas. B. Bypass Pumping during work activities (if necessary). C. Cleaning, inspection, and testing. D. Removal of existing storm sewerage pipe and drainage structures FIELD MEASUREMENTS A. Contractor shall be responsible for the horizontal and vertical layout of the proposed sewers and structures based upon the information shown on the contract drawings. If the Contractor deems that additional data may be required, the Owner must be notified in writing prior to the submittal of the bid. B. Verify that survey bench mark, control point, and intended elevations for the work are as shown on the drawings and that the layout can be performed based upon the information provided on the drawings. C. Where existing utilities are to be crossed or connect into by proposed facilities, the Contractor shall excavate and obtain facility elevations prior to the start of the sewer work. The Contractor shall immediately notify the Owner and Professional of any discrepancies, other than what has been assumed on the plan, so that adjustments and/or relocations can be made. D. Upon completion of the work activities, the Contractor must provide the Owner with As-Built Drawings of all sewers installed, denoting horizontal location on the site, with top and invert elevations of the sewers. The Owner reserves the right to request that the As-Built Drawings be signed and sealed by a registered professional land surveyor QUALITY ASSURANCE A. Regulatory Requirements: Comply with applicable requirements of federal, state, and local laws, regulations and codes having jurisdiction at project site. B. Reference Standards and Specifications: 1. Applicable requirements of standards and specifications ( )

2 1.05 SUBMITTALS referenced herein, apply to this section in addition to the following publications of the issues listed below, but referred to by basic designations only, form an integral part of this Specification. 2. Pennsylvania Department of Transportation (PennDOT) Standards: Form 408, Latest Edition. 3. American Society for Testing and Materials (ASTM) Specifications. 4. Standard Specifications for Materials and Construction for Local Governments and Authorities. A. Product Data for all piping. B. Shop Drawings for all sewer appurtenances proposed for use, including but not limited to precast concrete structures, including frames, grates, boot connectors, etc. C. Upon completion of work, accurately survey and record actual locations of pipe runs, connections, structures, with associated tops and invert elevations. An As-Built Plan must be submitted, and the Owner reserves the right to request that a Professional Surveyor certify the location and elevations of the facilities installed PROJECT CONDITIONS A. Coordination: Coordinate this work with the work of other Sections to avoid any delay or interference with other work. B. Cooperation: Coordinate this work with the work of other Sections to avoid any delay in progress of building or any interference with progress of other work. C. Where existing utilities are to be crossed by proposed construction, the Contractor shall excavate test pits, or verify by other means, prior to the start of any construction activities to determine the existing elevations, materials, and sizes. Test pit information shall be supplied to the Owner prior to the start of construction to permit adjustments that may be required to avoid conflict. The Contractor must also verify, prior to construction, the elevation of the any utilities proposed to be crossed or where connection to new facilities are proposed, to determine if any change in proposed grade is necessary. D. Existing Utilities 1. PA One Call: The Contractor's attention is called to the fact that he may go across gas, cable television, electric and water lines, so, before starting any work, all utility companies must be notified so their service lines can be located. The Contractor shall notify Pennsylvania One Call System, Inc. at a minimum of three working days prior to any construction on site. The Contractor shall verify the depth of ( )

3 these lines well in advance of any construction in order to adjust the new line in case of any conflict. 2. Locations indicated are approximate based upon information available at the time of site design work. Contact local "PA One Call System" prior to excavation and verify exact locations of all existing utilities. 3. Perform necessary exploratory tests for verification if necessary. The Owner and Professional will assume no responsibility for hazardous conditions, losses and accidents arising out of failure to perform by this Contractor or other Parties or both. 4. Should incorrectly charted or uncharted piping or other utilities be encountered during excavation, consult utility Owner immediately for directions. Cooperate with Owner and utility services in keeping respective services and facilities in operation. Repair damaged utilities to the satisfaction of utility Owner. 5. The Contractor shall remove and legally dispose off-site the existing storm sewer piping and drainage structures specified on the Construction Drawings, including all paving materials required to be removed in order to gain access to the pipe and any pipe trench backfill material deemed to be unsuitable for reuse as backfill by the Owner s Representative. The Contractor shall ascertain the alignment of the sewer pipe to be removed and layout the alignments of proposed pavement sawcuts for review and acceptance of the Owner s Representative prior to initiating sawcutting operations. The Contractor shall backfill the trenches created by the pipe and drainage structure removals with the materials and in the manner as shown on the Pipe Bedding and Trenching Detail. Materials excavated during the removal operations, deemed to be acceptable as backfill material by the Owner s Representative may be reused as backfill, at the discretion of the Contractor. The Contractor shall restore the finished ground-surface to, or better than, its condition prior to the pipe and structure removals. E. Disposition of Utilities: 1. Observe rules and regulations governing respective utilities during execution of work of this Section. 2. Adequately protect all active utilities from damage. 3. Remove or relocate all active utilities only as shown or as specified. 4. Remove, plug or cap inactive and abandoned utilities encountered in excavating and grading operations. In absence of specific requirements, remove, plug or cap such utilities lines at least 3 feet outside building walls or as required by local regulations. 5. No additional compensation shall be paid to the Contractor in ( )

4 the event that an existing utility line must be replaced due to damaged as a result of the construction activities. F. Benchmarks, Monuments and Other Reference Points: Protect from damage and displacement; if disturbed or destroyed, replace at Contractor s expense. PART 2 - PRODUCTS 2.01 BEDDING MATERIAL A. Shall be angular or subangular No. 57 aggregate meeting grading requirements of PennDOT Specifications Section PIPE A. Polyethylene Pipe for Storm Sewer: Storm Sewer Pipe (for sizes up to and including 36" diameter) shall be corrugated polyethylene pipe type S (smooth lined interior) conforming with standards of AASHTO M294 Type S. Pipe to be ADS N-12 by Advance Drainage Systems or approved equal. Pipe shall be perforated, where so specified. All fittings and associated appurtenances shall be as recommended by the manufacturer. B. Corrugated Plastic Tubing for Underdrains: ASTM F405 flexible type, perforated with required fittings, installed with perforations down; provide with geotextile- surround where indicated. C. Polyvinylchloride Pipe (PVC): PVC sewer pipe shall conform to Standard Specifications for Rigid Polyvinyl chloride Compounds, ASTM D-1784, Class B or C or C. The pipe shall be produced using a continuous extrusion process employing a prime grade l of unplasticized polyvinyl chloride. PVC sewer pipe 15 inches in diameter or smaller shall meet the requirements of ASTM D 3034 SDR 35 minimum; pipe and fittings larger than 15 inches in diameter shall meet the requirements of ASTM F 679, wall thickness T-1, pipe stiffness of 46 psi. The joint system shall be an integral bell gasketed joint, which forms a watertight seal. D. Fittings and Accessory Components: Provide proper fittings for installation and connection of lines as shown on construction plans meeting applicable requirements of associated types of pipe. All materials shall be provided and installed in strict accordance with manufacturer s instructions INLETS / MANHOLES A. All inlets, drain basins and yard drains, shall be as detailed and noted on the Contract Drawings. B. Precast concrete units are permitted for all storm manholes and inlets, and shall conform to ASTM Specification C 478 and shall be as manufactured by United States Concrete Pipe Company or approved equal. Yard Drain structures shall consist of 24"-diameter Reinforced Concrete Pipe, or approved equal. Precast structures shall meet PennDOT Form 408 Specifications and federal and local standards. The ( )

5 connection of all pipes to manholes must be made via prefabricated factory openings or core drilled openings using a Kor-N-Seal Expansion Band connector or approved equal. Drain Basins to be constructed as components of the Infiltration Areas shall be of heavy-duty PVC as manufactured be Nyloplast, or Owner-approved equal. (Nyloplast America, 3130 Verona Avenue, Buford, GA 30518, Telephone: , Fax: ). C. Brick: Brick for manholes, inlets, bulkheads, inlets and other drainage structures shall be solid concrete brick, hard burned common brick having low absorption, or well-burned No.2 paving brick. D. Grates, Frames, and Covers: 1. Shall be cast of gray iron and shall be sound true to form and thickness, and fitted and match-marked to assure proper seating. Castings shall be free from burnt-on sand and other injurious defects. 2. Standard Manhole Frames shall conform to the Standard Detail shown on the Contract Drawings. Otherwise, manhole frames and covers to be Neenah Foundry Co. No. R-1573 or Allegheny Foundry Co. Frame Pattern No. 109 and Cover Pattern No. 110, or approved equal. 3. Standard Inlet Frames shall be Type M Series No or 3574 as manufactured by Neenah Foundry Company, or approved equal. A Bicycle Safe Grate shall be installed in all Pedestrian Traffic Areas which would consist of the parking lots. A Basket Type Grate shall be installed in drainage channels, and a diagonal Grate shall be installed at other locations as specified on the Drawings. Yard Drains shall be topped with a Beehive Grate and Frame No. R-2564, as manufactured by Neenah Foundry Co., or approved equal. 4. All storm manhole covers to bear the words Storm Sewer. 5. The contact surfaces of all manhole covers and corresponding supporting rings in the frames shall be machined to provide full perimeter contact. E. An adjusting ring equal to R1979-H as manufactured by Neenah Foundry Co., or approved equal, shall be provided for each manhole in a street or parking lot area. F. Manhole and/or Inlet Steps shall be Allegheny Foundry Co. Pattern No. A-1488 or Polypropylene Plastic Coated (ASTM D-2146 Type II CR ) 3/8 Grade 40 Deformed Steel Bar (ASTM A-615), or approved equal. G. Mortar shall be ASTM C-270 Type M. Prepackaged masonry cement will not be acceptable. Mortar shall consist of one (1) part cement to two and one-half (2-1/2) parts sand, and water. 1. Cement shall conform to ATM C-150, Type Sand shall conform to PennDOT Section ( )

6 3. Water shall be clean and free from oil, acids, salts or other injurious substances CONCRETE AND REINFORCEMENT A. Concrete for storm sewer appurtenance construction shall be 4,000 psi mix. Joint mortar shall be 1:2 Portland cement-sand mix, masonry mortar to be 1:3. At Contractor's option, hydrated lime may be substituted for cement, not to exceed 10% of cement used in masonry mortar. B. The minimum compressive strength for all concrete and concrete sections shall be 4,000 p.s.i. C. Reinforcement: Steel conforming to the following: 1. Fabric: ASTM A-185, welded wire fabric, plain. 2. Reinforcement Bars: ASTM A-615, Grade 60, deformed, epoxy coated. D. Concrete Encasement: 1. Storm sewer piping which passes beneath the building shall be encased in concrete, as shown and detailed on the Contract Drawings. 2. Loose material shall be removed from the trench and the concrete placed with continuous contact with undisturbed soil on the sides and bottom of the trench. A base course of concrete shall be screeded to a level that ensures the pipe to be at the specified grade. Each length of pipe shall be held in rigid alignment and braced to prevent flotation. The pipe joints shall be carefully sealed to prevent entrance of concrete mortar and water into the joints. Jointing of the pipe shall be done before the encasement is poured. The Contractor has the option to construct formwork, in lieu of placing the encasement concrete against undisturbed soil trench walls. No additional monies will be paid to the Contractor in the event the Contractor chooses this option. 3. The minimum compressive strength of the concrete encasement shall be 4000 psi. 4. Reinforcement bars shall not be placed within the concrete encasement. PART 3 - EXECUTION 3.01 EXAMINATION A. Examine areas in which work is to be performed. Report, in writing, to the Owner's Representative, all prevailing conditions that will adversely affect satisfactory execution of work. Do not proceed with ( )

7 work until unsatisfactory conditions have been corrected. B. Starting work constitutes acceptance of the existing conditions and this Contractor shall then, at his expense, be responsible for correcting all unsatisfactory and defective work encountered. C. Contractor shall assume full responsibility for safeguarding and protecting all poles and other structures which may occur near to his work or in any way may be affected by any of his work under this Contract TRENCHING, BACKFILLING AND COMPACTION A. Trenching, backfilling and compacting: In accordance with applicable requirements of Section B. Generally, excavate to the line and grade shown. The excavation shall not be carried closer than to within two inches of final grade until the pipe is ready to be installed. Fine graders just ahead of the pipe laying operation shall remove the remaining two inches. C. The Infiltration Areas shown on the Contract Drawings must not be constructed or placed in service until the entire contributing drainage areas have been stabilized. Runoff from untreated, recently constructed areas within the drainage area may otherwise load the newly formed area with a large load of fine sediment, seriously impairing the natural infiltration ability of the Infiltration Area (basin) floors. D. Backfilling from top of bedding to a point at least one foot over the top of pipe barrel shall be placed by hand in six (6) inch layers and thoroughly tamped into place around the pipe. Extreme care shall be exercised to the level one foot above pipe barrel to insure that no damage is caused to the pipe or that its alignment or grade is not disturbed in any way. Only clean materials may be used in this operation, clean earth (no rocks) sand or rock dust INSTALLATION OF SEWERS A. Install sewer lines in straight line and on uniform rate of grade between points where changes in alignment or grade are shown. Bed the barrel of pipe firmly at required line and grade. Keep stopper in mouth of pipe when pipe-laying is not in progress. Set bell of pipe upstream. Support barrels of pipe continuously and scoop out space for proper clearance of bell. B. Installation of pipe shall be against the flow and shall be to grades and alignment indicated on Drawings to provide a smooth, uniform flow line. Under no circumstances shall pipe be blocked to grade. C. Pipe shall not be installed during undesirable weather conditions. Under no circumstances shall pipe be installed in water. D. All joints shall be kept free of dirt, watertight and thoroughly secured. Contractor shall take all measures necessary to insure a tight joint ( )

8 E. Pipe Bedding: The trench bottom shall be filled with material in six (6) inch maximum lift and compacted to 95% maximum density ASTM D up to the spring line of the pipe. The remainder of the trench shall be backfilled as specified on the Drawings. F. All pipe entering structures shall be cut flush with the inside face of the structure, and the cut ends of the pipe surface of the structure shall be properly rounded and finished so that there will be no protrusion, ragged edges or imperfections that will impede the flow of water or affect the hydraulic characteristics of the installation. G. After installed piping has been tested and inspected, backfill excavations with approved material. Tamp and compact in place. Tamp carefully around pipe and above top of pipe in layers not over 6 inches. Observe care in backfilling not to disturb pipe. H. Provide granular bedding and dewatering materials and methods required to facilitate installation. I. Bypassing when connecting to existing facilities shall be performed by pumping flow from a manhole upstream of the work area to a manhole below the work area. Other means of bypass pumping may be accepted upon approval of the Owner s Representative. The pumps(s) and bypass lines shall be of adequate capacity and size to handle the flow. J. All proposed direct connections to sewer pipe shall be made by core drilling and performing the connection in accordance with the detail provided on the Plans CONSTRUCTION OF STRUCTURES A. Size of excavation shall be sufficient to leave a minimum of twelve (12) inches and a maximum of twenty-four (24) inches clear between structure and the excavation or bracing. Any over-depth excavation below such appurtenances that has not been directed will be considered unauthorized and shall be refilled with bedding material at no additional cost. B. Masonry work shall be laid up true and plumb and horizontal joints shall not be more than ½. Masonry units shall be laid in full bed of mortar and joints in each course shall be filled solid with mortar before another course is laid on top. Brick shall be wet before being laid in warm weather. Brick shall not be laid in freezing weather. Protect brick work from the weather when storming or freezing and at other times when necessary during the progress of the work. Inlet frames shall be set in a full bed of mortar and at the elevation established by the Contract Drawings. C. Precast structures shall be set on properly prepared granular or concrete subbase providing full support to unit. D. All inflow / outflow pipes shall be cut flush with inside face of inlet/manhole and parged with cement mortar. E. Concrete base for precast inlets/manholes shall have a minimum thickness of eight (8) inches if on earth and six (6) inches if on ( )

9 rock and shall be poured in place using concrete. Concrete flow lines shall be poured in all inlets to direct the flow of water to the outflow pipe. Casting shall be set in full mortar bed. Care shall be exercised to see that frames and grates are to exact finished grades specified on the Contract Drawings. F. Upon installation of all Concrete Structures, Manholes and Inlets, and piping networks in and out of such structures, the Contractor shall pour a concrete invert in the structures to direct low flow from the inlet pipe(s) to the outlet pipe(s). The poured in place concrete invert shall have a minimum depressed area of four (4) inches for low flow 3.06 FIELD QUALITY CONTROL A. Tests: 1. Visual Test: All sewer lines shall be inspected visually by the Contractor and checked by the Owner's Representative to verify accuracy of alignment and freedom from debris and obstructions. The full diameter of the pipe should be visible when viewed between consecutive manholes. The method of test can be photography, closed circuit television or visually lamping with mirrors and lights. 2. Deflection Testing: The maximum allowable pipe deflection is 7.5 %. If the Owner's Representative directs as a result of the visual test, a "go, no-go" mandrel or sewer ball shall be used to prove pipe deflection is within allowable limits. The Contractor may, at his option, use a deflectometer, calibrated television or photography PROTECTION OF PROPOSED STRUCTURES Use of heavy equipment over or across the storm drainage system at any stage of construction shall be at the risk of the Contractor. Displacement or injury to the system due to such operation shall be repaired or replaced when directed at no additional cost to the Owner CLEANING OF NEW SEWERS Upon completion of site drainage facilities, if deemed necessary by the Owner, the entire sewer system that was installed by the Contractor shall be flushed using high pressure water jets to remove dirt and other foreign material from pipe and related structures. Any debris shall be screened at the downstream point of connection to the existing storm/sanitary system and not be allowed to enter the system. Debris shall be removed and disposed of at an approved offsite location ABANDONMENT OF EXISTING STORM SEWER A. The Contractor shall close open ends of abandon underground piping indicated to remain in place. Include closures strong enough to ( )

10 END OF SECTION withstand hydrostatic and earth pressures that may result after ends of abandon pipe have been closed. Any of the following procedures may be used: 1. Close open ends of pipe with at lease 8" thick, brick masonry bulkheads. 2. Close open ends of pipe with threaded metal caps, plastic plugs, or other acceptable methods suitable for size and type of material being closed. Do not use wood plugs ( )