Town of Ashland, MA Specifications

Resilient wedge valves shall be the products of the Mueller Valve Co., Decatur, Illinois, or Kennedy Valve Manufacturing Co., Elmira, New York, or approved equal. Resilient wedge valves shall only be permitted on hydrant laterals.

Resilient wedge valves shall be iron body, resilient seated type. The valves shall be designed for two hundred (200) pounds per square inch working pressure and four hundred (400) pounds per square inch test pressure. Valves are to have o-ring seals and a nonrising stem. Valves shall have a two-inch operating nut. Valves shall open left.

Resilient wedge valves shall meet the most recent version of the AWWA standard C501. Resilient wedge valves shall have mechanical joint ends. Valves shall be connected directly to anchor tees on all hydrant branches.

Butterfly valves.

The butterfly valves shall have a cast-iron body and shall conform to the AWWA specifications for Rubber-Seated Butterfly Valves, Designation:C504, except as otherwise specified herein. The butterfly valves shall be Model No. 450, manufactured by M&H Valve Co., or approved equal. The valves shall have mechanical joint ends when buried and flanged ends where exposed.

The valves shall be Class 150B and suitable for a nonshock shutoff pressure of one hundred fifty (150) pounds per square inch. The valves shall provide bubble-tight shutoff at two hundred (200) pounds per square inch when tested for leakage in accordance with the above-mentioned AWWA C504. The valve shall be rejected if it does not pass this test.

Butterfly valve designs utilizing continuous lining on the internal body surfaces and extending over the flanges will not be acceptable. Valve disks shall seat at an angle of ninety degrees (90°) to the axis of the pipe.

Valve seats shall be of molded natural rubber. Rubber seats may be attached to the body or the disk. If the rubber seat is attached to the disk, the seat ring on the body shall be of stainless steel. The valve disk shall be of either cast Ni-Resist or cast iron Class 40 conforming to ASTM A48, Specification for Gray Iron Castings.

Rubber seats mounted on the disk shall be securely clamped to the disk. All clamps, retaining rings and their fasteners shall be Series 300 stainless steel.

The valve shaft shall be Type 300 stainless steel or carbon steel with stainless steel joints. The valve disk and shaft connection shall be by means of mechanically secured taper pins extending through the disk and shaft. Taper pins, lock washers and nuts shall be 18-8 stainless steel. The shaft seals shall be designed for the use of standard chevron-type packing or standard o-ring seals.

The manual operating mechanism shall be firmly fixed to the valve body. The operator shall be permanently lubricated and shall be totally enclosed with a cast-iron case, and the hand wheel or two-inch nut for buried valves shall turn counterclockwise to open. The operator for buried valves shall be suitable for submersion. The operator shall be traveling-nut type designed to withstand four hundred fifty (450) foot-pounds of input torque at full open or closed positions without damage to the valve or operator.

Installation.

All valves shall be carefully erected and supported in their respective positions free from all distortion and strain. Care shall be taken to prevent damage or injury to the valves or appurtenances during handling and installation.

All material shall be carefully inspected for defects in workmanship and materials, all debris and foreign material shall be cleaned out of valve openings and seats, all operating mechanisms shall be operated to check their proper functioning and all nuts and bolts shall be checked for tightness. Valves and other equipment which do not operate easily or are otherwise defective shall be repaired or replaced at the contractor's expense. Mechanical joints shall be torqued to manufacturer's specifications.

Buried valves and valve boxes shall be set plumb and centered with the valve boxes directly over the valves. Earth fill shall be carefully tamped around the valve box to a distance of four (4) feet on all sides of the box or to undisturbed trench face, if less than four (4) feet.

Valve boxes.

Each valve shall be provided with a box. Covers shall have two (2) lifting holes, and the word "WATER" cast on the top. The top of the cover shall be flush with the top of the box rim.

Valve boxes shall be tar-coated cast iron and of the adjustable sliding, heavy pattern type. They shall be so designed and constructed as to prevent the direct transmission of traffic loads to the pipe or valve. The upper or sliding section of the box shall be provided with a flange having sufficient bearing area to prevent undue settlement. The lower section of the box shall be designed to enclose the operating nut and stuffing box of the valve and to rest on the backfill. The boxes shall be adjustable through at least six (6) inches vertically without reduction of the lap between sections to less than six (6) inches.

The inside diameter of boxes shall be at least four and one-half (41/2) inches, and the lengths shall be as necessary to suit the ground elevation [normal pipe cover five and zero-tenths (5.0) feet].

Tapping sleeve and valve.

The tapping sleeve and valve shall consist of a split cast-iron sleeve tee with mechanical joint ends on the main and a flange on the branch, and a tapping-type resilient wedge valve with one (1) flanged and one (1) mechanical joint end. The valve shall conform to the requirements hereinbefore specified for resilient wedge valves. The contractor shall be responsible for verifying the outside diameter of the pipe to be tapped.

Before backfilling, all exposed portions of any bolts used to hold the two (2) halves of the sleeve together shall be heavily coated with two (2) coats of bituminous paint comparable to Inertol No. 66 Special Heavy. Sleeves shall be of cast iron conforming to ASTM A-126 Class B, furnished with rubber gaskets. Gaskets shall cover the entire area of flange surfaces.

Tapping sleeves and valves shall be made by Ludlow-Rensselaer Valve Co., Inc., Troy, New York: Eddy-Iowa Div., James B. Clow & Sons, Inc., Chicago, Illinois; A.P. Smith Mfg. Co., East Orange, New Jersey; Mueller Valve Co., Decatur, Illinois, or be approved equal products.

Hydrants.

The hydrants shall conform to the requirements of AWWA Standard for Dry Barrel Fire Hydrants for Ordinary Water Works Service, Designation: C502-80, or latest revision.

The hydrants shall have one (1) pumper of four and one-half (41/2) inches and two (2) hose connections of two and one-half (21/2) inches, NST, with a six-inch mechanical joint shoe. The hydrant shall be equipped with a main valve of five and one-fourth (51/4) inches and shall have bronze-to-bronze seatings and open left. Hydrants shall also have an eight-inch ductile-iron lower barrel and a fusion-bonded epoxy-coated shoe. There will be a travel-stop nut located on the upper stem to prevent damage due to excessive force. Upper stem threads will be lubricated by the use of an all-temperature grease and sealed by double o rings.

For the purpose of standardization, hydrants will be the Waterous Pacer-WB 67 or the U.S. Pipe Metropolitan.

The hydrants shall be thoroughly cleaned and given two (2) shop coats of paint in accordance with the above-mentioned AWWA Specification C502, latest edition. Paint color shall be federal safety red, as manufactured by Hydrant Hyde Paint, with reflective white bonnet and white caps.

The hydrant, with its buried valve and valve box, shall be set plumb and centered with the valve box directly over the valve. Backfill around the hydrant and valve shall be thoroughly compacted to a distance of four (4) feet on all sides of the box or to the undisturbed trench face if less than four (4) feet. The hydrant connecting pipe shall have at least five and one-half (51/2) feet of cover. The hydrant shall be set upon a slab of stone or concrete not less than four (4) inches thick and fifteen (15) inches square. The side of the hydrant opposite the pipe connections shall be firmly wedged against the vertical face of the trench with a poured concrete thrust block as indicated on the standard details. No less than five (5) cubic feet of broken stone shall be placed around the base of the hydrant at the location of the drain holes. Strict attention shall be given to ensure drainage holes are kept free of any concrete. Fifteen-pound roofing felt shall be placed between the concrete thrust block and the hydrant and drainage gravel. Backfill around the hydrant shall be thoroughly compacted to the grade line in a satisfactory manner. The hydrant and valve shall have the interiors cleaned of all foreign matter before installation and shall be inspected in both the open and closed position.

The bury of the hydrant shall be of sufficient length to allow the hydrant to be set at the proper elevation, as shown on the standard details. Extensions shall be furnished and installed at the contractor's expense when required for greater depths.

All hydrants shall be mechanically connected to the water mains using a main line anchoring tee, fitted to take a six-inch resilient wedge valve mechanically connected on the side outlet, and a six-inch mechanical joint cement-lined cast-iron pipe to the hydrant. Retaining glands shall be used at all joints between the shutoff valve up to and including the hydrant. All bolts shall be torqued to manufacturer's specification.

(8)

Before exposure to the weather and after thorough cleaning to remove all rust, dirt, grease and other foreign matter, the equipment and appurtenances specified herein shall be painted in the shop as specified hereinafter. Ferrous surfaces which will be submerged shall be cleaned by sandblasting to remove all foreign matter. Following cleaning, the surfaces shall be painted in the shop as follows: interior and exterior surfaces of valves and valve appurtenances shall be given a shop finish of an asphalt varnish conforming to Federal Specification TT-V-51C, for Varnish Asphalt. Ferrous surfaces obviously not to be painted shall be given a shop coat of grease or other suitable protective coating.

Corporation cocks. Corporation cocks shall be bronze and shall be the approved equal of Mueller Valve Co., Decatur, Illinois, or Ford Meter Box Co., Wabash, Indiana, for copper service tube. End joints shall be compression fittings.

Tapping saddles. Tapping saddles shall be required on all cast-iron, polyvinyl chloride (PVC) and asbestos-cement (A.C.) pipe. Tapping saddles shall be Model 313, as manufactured by S&W.

Curb stops. Curb stops shall be bronze with a lapped, ground key and shall be the approved equal of Mueller Valve Co., Decatur, Illinois, or Ford Meter Box Co., Wabash, Indiana, for copper tube service, compression joint.

Copper tubing. For all residential services, type K copper tubing as noted in section M below may be allowed from the water main to the curb stop and to the meter connection for all service connections.

[Amended 11-28-2012 STM, Art. 12]

Meters. For the purposes of standardization, water meters shall be Trident T-10, provided with an ARB external reader and forty (40) feet of cable. Each meter shall be supplied with one (1) bent meter connection and one (1) straight meter connection. Meter connection nuts will have a hole in nut for purposes of sealing.

PE Tubing. PE tubing may be allowed from the water main to the curb stop and to the meter connection for all residential service connections. Prior to approval, the applicant shall verify in writing to the Town that no petroleum constituents are present in subsurface soil in the vicinity of the service. If subsurface petroleum constituents are present in the subsurface soil in the vicinity of the service then type K copper tubing shall be required from the water main to the curb stop and to the meter connection for all service connections. Otherwise, plastic water services shall be Polyethylene manufactured of PE3408 materials with SDR-9 minimum wall thickness, as defined in ASTM D3350. Polyethylene pipe shall be blue plastic and pressure class 200 psi. Dimensional and performance characteristics shall conform to the requirements of AWWA C901. The use of polyethylene pipe and tubing may be allowed for water services two (2) inches or under in diameter (4-inch and larger diameter water services shall use cement lined ductile iron water pipe). Polyethylene pipe shall be installed with enough slack to compensate for settlement and compaction and shall be laid on a bed of sand with six inches below, above, and to either side of the tubing. Sand shall meet the specifications of the Massachusetts Department of Transportation Standard Specifications for Highways and Bridges M1.04.0 Type a. Tubing shall EITHER include an embedded trace wire as provided by Endopoly PE3408/PE4710 High Density Polyethylene Pipe manufactured by Endot Industries, Rockaway, NJ, or approved equal OR shall have a trace wire laid no more than six inches above the pipe. If trace wire is used than the wire shall be continuous, with no splices, from the main to the structure. Trace wire shall be Copperhead Reinforced Tracer Wire by Copperhead Industries, Monticello, MN, or approved equal.

[Added 11-28-2012 STM, Art. 12]

§ 334-57 Cement-lined ductile-iron pipe and fittings.

General.

The contractor shall furnish, handle, haul, lay, joint, test and disinfect all cement-lined Class 52 ductile-iron pipe, including fittings and appurtenant work.

The pipe shall be installed with a minimum of five and one-half (51/2) feet of cover. Where the pipe cannot be reasonably installed with this cover, the contractor shall furnish and install insulation as approved by the Division. The contractor must have permission from the WSD to install any pipe with less than five and one-half (51/2) feet of cover, prior to installation.

For buried ductile-iron pipelines, the contractor shall use push-on-joint-type pipe. All fittings for push-on-joint pipe shall have mechanical joint ends. The pipe and fittings shall be cement-lined and coated. The pipe joints shall have rubber gaskets.

In all cases, water mains shall be installed twelve (12) feet from the property line on proposed streets.

Standard specifications.

Class 52 ductile-iron pipe shall conform to ANSI A21.50 (AWWA H3) and ANSI A21.51 (AWWA C151).

Class 250 ductile-iron fittings shall conform to ANSI A21.10 (AWWA C110).

Short-bodied Class 350 ductile-iron fittings shall conform to ANSI A21.53 (AWWA C153).

Pipe joints. Where required, pipe and fittings shall be furnished with restraining glands, approved lugs or hooks cast integrally for use with bolts or bridle rods and socket clamps to keep the piping from pulling apart under pressure.

Flange joints shall conform to ANS-A21.10, except that special drilling or tapping shall be as necessary to ensure correct alignment and bolting. Flanged pipe shall use long-hub flanges which shall be screwed on tight at the foundry by machine before they are faced and drilled.

Mechanical joints shall conform to ANS-A21.11.

Push-on joints shall conform to ANS-A21.11.

Fittings.

Fittings shall be Class 250 ductile iron or cast iron. Class 350 short-bodied fittings may be used at the contractor's option. Unless otherwise indicated, fittings shall have mechanical joint ends.

Flanged fittings shall be faced and drilled in accordance with ANSI-A21.10, except that special drilling or tapping shall be provided as necessary to ensure correct alignment and bolting.

Pipe for use with couplings. Pipe for use with sleeve-type couplings shall be as specified above, except that the ends shall be plain (without bells or beads).

Sleeve-type couplings.

To ensure correct fitting of pipe and couplings, all solid sleeve-type couplings and accessories shall be furnished by the supplier of the pipe and shall be Class 350, ductile iron through twelve-inch diameter and Class 250 ductile iron for greater than twelve-inch diameter.

Couplings for buried pipe shall be iron and shall be solid, mechanical joint sleeve. The couplings shall be provided with epoxy-coated galvanized-steel bolts and nuts.

All couplings shall be provided with gaskets.

Split couplings. For connecting cast-iron pipe, split couplings may be used instead of sleeve-type couplings. Split couplings shall be made of malleable iron and shall be suitable for use with grooved-end or shouldered-end cast-iron pipe. They shall be Victaulic Couplings made by the Victaulic Co. of America, Elizabeth, New Jersey; Gruvagrip couplings made by Gustin-Bacon Mfg. Co., Kansas City, Missouri; Groove couplings made by Eastern Malleable Iron Co., Pittsburgh, Pennsylvania; or approved equal products.

Lining and coating.

All pipe and fittings shall be lined and coated as specified below.

The inside of pipes and fittings shall be given a cement lining and bituminous seal coat in accordance with ANSI-A21.4.

The outside of pipe and fittings shall be coated with the standard bituminous coating specified under the appropriate ANSI standard specification for the pipe and fittings.

Machined surfaces shall be cleaned and coated with a suitable rust-preventative coating at the shop immediately after being machined.

Inspection and testing.

All pipe and fittings shall be inspected and tested at the foundry as required by the standard specifications to which the material is manufactured. The contractor shall furnish, in duplicate, to the WSD sworn certificates of such tests.

In addition, the WSD reserves the right to have any or all pipe, fittings and special castings inspected and/or tested by an independent service at either the manufacturer's plant or elsewhere. Such inspection and/or tests shall be at the WSD's expense.

Pipes and fittings shall be subjected to a careful inspection and a hammer test just before being laid or installed.

Handling and cutting pipe.

The contractor's attention is directed to the fact that cast-iron fittings and cement linings are comparatively brittle. Every care shall be taken in handling and laying pipe and fittings to avoid damaging the pipe and linings, scratching or marring machined surfaces and abrasion of the pipe coating or lining.

Any fitting or pipe showing a crack or which has received a severe blow that may have caused an incipient fracture, even though no such fracture can be seen, shall be marked as rejected and removed at once from the work.

In any pipe showing a distinct crack or deformity and in which it is believed there is no incipient deformity beyond the limits of the visible deformity, the deformed portions, if so approved, may be cut off by and at the expense of the contractor before the pipe is laid so that the pipe used may be perfectly sound. The cut shall be made in the sound barrel at a point at least twelve (12) inches from the visible limits of the deformity. Edges of pipe at the cut shall be beveled to eliminate all sharp edges.

Except as otherwise approved, all cutting shall be done with a machine suitable for cutting ductile-iron pipe.

Hydraulic squeeze cutters are not acceptable for cutting ductile iron pipe. Travel-type cutters and guillotine or rotary-type abrasive saws may be used. All cut ends shall be examined for possible defects caused by cutting.

The contractor's attention is directed to the fact that damage to the lining or pipe or fittings will render them unfit for use; he shall use the utmost care in handling and installing lined and coated pipe and fittings to prevent damage. Protective guards shall not be removed until the pipe is to be installed.

Lined and coated pipe and fittings shall be installed as and assembled with approved packing or gaskets of the type recommended by the pipe manufacturer for the particular lining used.

Installing pipe and fittings.

No defective pipe or fittings shall be laid or placed in the trench, and any piece discovered to be defective after having been laid or placed shall be removed and replaced by a sound and satisfactory piece.

Each pipe and fitting shall be cleared of all debris, dirt, etc., before being laid and shall be kept clean until accepted in the complete work.

Pipe and fittings shall be laid accurately to the lines and grades indicated on the drawings or as required. Care shall be taken to ensure a good alignment both horizontally and vertically. The pipe shall be laid on wood blocks, with two (2) blocks required for each length of pipe for support.

In buried pipelines, each pipe shall have a firm bearing along its entire length.

The deflection of alignment at a joint shall not exceed the appropriate permissible deflection as specified in the tabulation titled "Pipe Deflection Allowances."

	Pipe Deflection Allowances
	Maximum Permissible Deflection* (inches)
	Size of Pipe (inches)	Push-on-Joint
	8	19
	10	19
	12	19
	16	15
	* NOTE: Maximum permissible deflection for eighteen-foot length. Maximum permissible deflections for other lengths shall be in proportion of such lengths.

Castings to be encased in masonry shall be accurately set with the bolt holes, if any, carefully aligned.

Immediately prior to being set, castings shall be thoroughly cleaned of all rust, scale and other foreign material.

Assembling push-on-joint pipe.

Joining of push-on-joint pipe shall conform to the American Water Works Association AWWA Standard Specifications, Designation: C600, latest revision.

If effective sealing of the joint is not attained, the joint shall be disassembled, thoroughly cleaned, a new gasket inserted and the joint reassembled.

Assembling mechanical joint fittings. Assembling of fittings with mechanical joint ends shall conform to AWWA Standard Specification: C600, latest revision. Thrust blocks and retainer glands shall be used at all valves, hydrants, fittings and bends in excess of forty-five degrees (45°) and shall be of the size and type as shown on the Hydrant Setting Detail and the Thrust Block Detail in the Standard Details. Precast concrete blocks may be used as thrust blocks, provided that they meet the same criteria as poured-in-place concrete and are acceptable to the WSD.

Temporary plugs. At all times when pipe laying is not actually in progress, the open ends of pipe shall be closed by temporary watertight plugs or other approved means. If water is in the trench when work is resumed, the plug shall not be removed until all danger of water entering the pipe has passed.

Bolted joints.

Materials for bolted joints shall be as hereinbefore specified.

Before the pieces are assembled, rust-preventative coatings shall be removed from machined surfaces. Pipe ends, sockets, sleeves, housings and gaskets shall be thoroughly cleaned, and all burrs and other defects shall be carefully smoothed.

If effective sealing of the joint is not attained at the recommended maximum torque, the joint shall be disassembled and thoroughly cleaned, then reassembled. Bolts shall not be overstressed to tighten a leaking joint. A torque wrench shall be used.

Pressure and leakage tests.

Except as otherwise directed, all pipelines shall be given combined pressure and leakage tests in sections of approved length. The contractor shall furnish and install suitable temporary testing plugs or caps; all necessary pressure pumps, pipe connections, meters, gates and other necessary equipment; and all labor required. The WSD shall have the privilege of using its own gauges.

Subject to approval and provided that the tests are made within a reasonable time considering the progress of the project as a whole and the need to put the section into service, the contractor may make the tests when he desires, utilizing a testing company approved by the WSD. However, pipelines in excavation or embedded in concrete shall be tested prior to the backfilling of the excavation or placing of the concrete, and exposed piping shall be tested prior to field painting.

Unless it has already been done, the section of pipe to be tested shall be filled with water of approved quality, and all air shall be expelled from the pipe. If hydrants or blowoffs are not available at high points for releasing air, the contractor shall make the necessary excavations and do the necessary backfilling and make the necessary taps at such points and shall plug said holes after completion of the test.

The section under test shall be maintained full of water for a period of twenty-four (24) hours prior to the combined pressure and leakage test being applied.

The pressure and leakage test shall consist of first raising the water pressure (based on the elevation of the lowest point of the section under test and corrected to the gauge location) to a pressure of two hundred (200) pounds per square inch. If the contractor cannot achieve the specified pressure and maintain it for a period of one (1) hour, the section shall be considered as having failed to pass the pressure test.

Following or during the pressure test, the contractor shall make a two-hour leakage test by metering the flow of water into the pipe while maintaining in the section being tested a pressure of one hundred fifty (150) pounds per square inch. If the average leakage is equal to or less than that allowed under AWWA Standard C600, latest revision, for installation of that specific pipe, the section shall be considered as having passed the leakage test.

If the section fails to pass the pressure and leakage tests, the contractor shall do everything necessary to locate, uncover and repair or replace the defective pipe, fitting or joint, all at his own expense. Additional tests and repairs shall be made until the section passes the specified test.

Disinfecting and flushing.

The contractor shall disinfect all pipelines he has installed.

The contractor shall furnish all equipment and materials necessary to do the work of disinfecting and shall perform the work in accordance with the procedure outlined in the AWWA Standard for Disinfecting Water Mains, Designation: C651, latest revision, as approved by the WSD's representative. The chlorine dosage shall be such as to produce not less than ten (10) milligrams per liter residual after a contact time of twenty-four (24) hours. During the disinfection period, care shall be exercised to prevent contamination of water in existing mains.

After disinfecting treatment, the main shall be flushed with clean water until the residual chlorine content does not exceed zero and two-tenths (0.2) milligrams per liter.

The contractor shall dispose of the water used in disinfecting and flushing in an approved manner.

A bacteriological sample shall be taken and submitted to a laboratory approved by the WSD's representative with all costs borne by the contractor. Test results from the laboratory are to be sent directly to the Ashland Water and Sewer Division, Box 9, Ashland, Massachusetts, 01721, by the laboratory.

Failure of system.

The contractor will be required to make test excavations to ascertain that the proposed position of the connections to existing mains will be clear of joints, fittings or other obstructions.

If any failure occurs in connecting to existing mains, service shall be restored in the shortest possible time, the contractor working around the clock, if necessary. He shall cooperate with the WSD in notifying the consumers or supplying emergency water. If required by the WSD, the contractor shall make connections to water mains during night hours, on Sunday or at another off-peak time for the demand for water. The contractor shall be responsible for maintaining all existing services and repairing any damages to existing utilities.

§ 334-58 Backfilling, paving and materials.

Backfilling pipe trenches.

As soon as practicable after the pipes have been laid, backfilling shall be started. The contractor's attention is directed to backfilling trenches at pipe joints. At his own risk, the contractor may backfill the entire trench, including backfill at joints. He shall, however, be responsible for removing and replacing such backfill, at his own expense, in order to locate, repair or replace leaking or defective joints or pipe.

Tree stumps or roots twelve (12) inches or longer will be considered unsuitable material for backfilling of trenches. No stone, rock or pieces of bituminous pavement larger than twelve (12) inches in greatest dimension shall be placed in the backfill nor shall large masses of backfill be dropped into the trench in such a manner as to endanger the pipeline.

Should a sufficient quantity of excavated material be classified by the WSD as unsuitable for backfilling such that backfilling of the trench cannot be completed with the excavated material, the contractor shall supply gravel borrow to complete the backfilling.

Backfill of the trench up to a level of twelve (12) inches above the top of the pipe shall be done by hand shovel with earth fill free from stones having any dimension greater than three (3) inches.

This area of backfill is considered the zone around the pipe and shall be thoroughly compacted before the remainder of the trench is backfilled. Compaction of the zone around the pipe shall be done by use of power-driven tampers weighing at least twenty (20) pounds. Care shall be taken that material close to the bank, as well as in all other portions of the trench, is thoroughly compacted to a density of ninety-five percent (95%).

The remainder of the trench above the zone around the pipe shall be backfilled and compacted. Compaction of backfill in the remainder of the trench shall be done in layers not exceeding twelve (12) inches in depth and by use of power-driven tampers weighing at least twenty (20) pounds. Water jetting shall be used only when approved by the WSD.

Restoring trench surface. Where the trench occurs adjacent to paved streets in shoulders, sidewalks or in cross-country areas, the contractor shall thoroughly consolidate the backfill and shall maintain the surface as the work progresses. If settlement takes place, he shall immediately deposit additional fill to restore the level of the ground. Adjacent to streets and highways, the top twelve-inch layer of trench backfill shall consist of compacted gravel. If, in the opinion of the WSD, the top twelve-inch layer is unsuitable for use as subgrade or shoulder material, it may order the contractor to remove this layer and to provide gravel subbase. The contractor shall maintain repair of the trench for one (1) year from the date of surfacing or backfilling.

State highway paving. Work to be done on roads designated as state highways shall conform to the following subsections. References are made to sections and terms of the state highway specifications.

The gravel subbase shall conform to that as specified under Section 2E-8, Gravel Subbase, of the state specifications. The subbase shall be a minimum of twenty (20) inches, compacted measure, and shall be entirely new gravel subbase.

After backfilling has been completed and subgrades reestablished, a two-inch bituminous concrete Type I-1 temporary pavement shall be installed and maintained by the contractor. Permanent pavement shall not be placed until a period of at least ninety (90) days has elapsed from the time of trench backfilling.

When directed by the Superintendent or the Massachusetts Department of Public Works, the contractor shall remove the temporary pavement and regrade the gravel subbase for installation of permanent pavement. The permanent pavement shall consist of a six-inch cement concrete slab, a two-inch binder course and a one-half-inch-to-three-fourths-inch top course.

The concrete slab shall be cast-in-place conforming to Massachusetts standard specifications for Class F cement concrete and shall be high early strength. The slab shall be reinforced as required.

The binder course shall be Class I bituminous concrete pavement, Type I-1, and shall be in accordance with Section 460 of the standard specifications.

Upon completion of the binder course, the contractor shall install the surface treatment or top course which shall consist of Class I dense bituminous concrete, Type ST, machine laid. In the case of a transverse trench, the top course shall extend thirty (30) feet beyond the limits of each edge of the trench and vary in depth from three-fourths (3/4) inch to one-half (1/2) inch.

The contractor shall notify the District 4 Office of the Department of Public Works twenty-four (24) hours prior to the start of work. The District 4 Office is located at 519 Appleton Street, Arlington, Massachusetts, 02174, telephone number 648-6100. All work shall be done as directed by and to the satisfaction of the engineer from the Massachusetts Department of Public Works.

Temporary pavement (non-state highways).

Where directed by the WSD and immediately after backfilling, the contractor shall place temporary bituminous pavement between the edges of the existing pavement. It shall consist of Class I bituminous concrete pavement, Type I-1, two (2) inches thick, in accordance with Section 460 of the Standard Specifications for Highways and Bridges of the Department of Public Works of the Commonwealth of Massachusetts, dated 1973, and all amendments thereto.

The temporary pavement shall be repaired as necessary to maintain the surface of the pavement until replaced by the permanent pavement. When so directed by the WSD, the contractor shall remove the temporary pavement and regrade the subbase for installation of permanent pavement.

Permanent pavement (non-state highways).

The bituminous paving mixture, equipment, methods of mixing and placing and the precautions to be observed as to weather condition of base, etc., shall be in accordance with Section 460 of the Standard Specifications for Highways and Bridges of the Massachusetts Department of Public Works.

The bituminous concrete pavements shall consist of Class I bituminous concrete, Type I-1, as shown in Section 460 of the Standard Specifications for Highways and Bridges of the Massachusetts Department of Public Works.

The edges of the existing pavement shall be trimmed back to a reasonably smooth line subject to the approval of the Ashland Highway Division. Immediately prior to installing the binder course, the trimmed edges shall be stable and unyielding, free of loose or broken pieces, and all edges shall be thoroughly broom cleaned. The contact surfaces of bridge curbings, manholes, catch basins or other appurtenant structures in pavement shall be painted thoroughly with a thin uniform coating of bitumen (Specifications C-8) just before any mixture is placed against them.

The binder course shall be two and one-half (21/2) inches thick, compacted, and the mixture shall be within the composition limits of binder course as shown in Section M3.11.00 of Massachusetts Department of Public Works Standards. It shall be placed only between the edges of the existing pavement.

The top course of pavement shall be one and one-half (11/2) inches thick, compacted, and the mixture shall be within the composition limits of top course as shown in Section M3.11.00 of Massachusetts Department of Public Works Standards.

Pavement maintenance and repair. If points of settlement or holes appear in the temporary pavement, binder course pavement or top course pavement, the contractor shall repair the same within twenty-four (24) hours of notification by the WSD. In emergency situations, the contractor shall make repairs immediately.

Sidewalk and curbing replacement.

Where the replacement of sidewalks is required, the contractor shall construct either bituminous concrete sidewalks or cement concrete sidewalks, as determined in the field, to the required lines and grades and in accordance with these specifications.

If applicable, the contractor shall restore gravel sidewalks to a condition at least equal to that before the work was started.

Unsuitable material.

If material unsuitable for use in trenches is found (peat, muck, wood, tree stumps, roots, etc.), the contractor shall remove such material to the required width and depth and replace it with thoroughly compacted bank-run gravel as directed.