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HomeMy WebLinkAboutC 903 General SpecificationsSECTION 01010 - GENERAL CONDITIONS 1. The Indiana Department of Transportation, Standard Specifications 1999, are the basic materials and reference specification. The sections noted below for various items are to clarify the intent of the requirements for this project. Please f1L?!Qt that othPf SPCtions g( ingse %nfjnrds Specitif q(I(; ls. No construction is to occur within the Hamilton County Hi hw Dept. dedicated right of way nor may any storm sewer lines ay be installed until the Developer and their contractor recieve a signed set of plans from both the City of Carmel Engineer Department and the Hamilton County Surveyor's Office. 2. These specifications in themselves, or when combined with the American Institute of Architects (AIA Document A201) General Conditions of the contract for construction shall be considered as part of the contract. 3. By executing the Contract, Contractor represents that he has acquainted himself with the site and has made all evaluations and investigations necessary to a full understanding of any difficulties which may be encountered in performing the work within the time frame allotted. All construction operations must be constructed as shown in the approved construction drawings. Variances from the construction drawings must be approved by the appropriate department before it is constructed in the field. All items which are not constructed as shown in the approved drawings will result in the removal and reconstruction of the item(s) without any negotiations. r 4. Any soil investigation data furnished to Contractor by Owner shall be for the convenience of Contractor, and Owner will not be responsible for any variance in actual conditions with such data or interpretations or conclusions drawn therefrom. Data on subsurface conditions do not constitute a representation or warranty of the continuity of such conditions. 5. Contractor shall schedule a pre- construction conference with the Hamilton County Highway Dept., Surveyor's Office, and County SWCD Engineer prior to start of construction to review the plans and scope of project. Contractor shall obtain latest set of drawings prior to start of construction. Minor changes may be made if all reviewing agency approvals are not granted before bidding. Changes in cost shall be negotiated prior to physical construction based on unit prices submitted on the contract documents. 6. The Contractor shall contact all utility companies to locate all mains, conduits, service lines, etc. in the construction affected area. Existing utility structures are shown here in accordance with available information at time of design. The location and protection of utility structures and facilities, their support and maintenance during construction (in cooperation with applicable utility), is the express responsibility of the Contractor in the performance of the Contract and in the preparation of the bid. The contractor shall notify the engineer of any changes, errors or omissions found on these plans or in the field before work is started or resumed. Extra care should be taken where a long time period occurs between design and construction. 7. The contractor shall be responsible for obtaining or verifying that all permits and approvals are obtained from the respective private, City, County and State agency prior to starting construction. The contractor shall also be responsible to comply with the conditions set forth within each permit. 8. It is the responsibility of the developer and contractor to maintain quality control management throughout the project. Failure to do so may result in removal and replacement of the defective work. It is recommended that the developer have a qualified supervisor on the job at all times during construction. 9. It is essential that the work to be done in conjunction with this project be installed according to these plans and specifications. Upon completion, the Engineer will be required to certify to certain portions of this project. Therefore, it is necessary that the work being performed comply with these plans and specifications in order to obtain acceptance by the governing agency. Any damaged or defective work will be the contractor's responsibility to correct or replace. All changes or discrepancies in plans shall be reviewed with the engineer prior to implementing changes in field. 10. Maintain carefully all bench marks, monuments and other reference points; if disturbed or destroyed, contractor shall contact engineer. Boundary lines of property have been established on the plans and contractor shall exercise care that building lines are established in accurate conformity with dimensions indicated. For construction and grading purposes, a bench mark has been established; the elevation is indicated on the drawings. All vertical dimensions and final grades shall be established from the bench mark. 11. All quantities given on the prints, verbally or in the Scope of Work section are estimates and shall be confirmed by the bidding contractor. 12. Contractor shall be required to maintain records of all as -built drawings and construction activity during the construction process. All as -built drawings shall be submitted to the Engineer upon completion. SECTION 01020 - QUALITY OF WORK 1. Perform all work in the most workmanlike manner and according to the best standard practices. All work shall be free from faults and defects in workmanship. 2. Contractor shall be soley responsible for quality control of the work and shall maintain quality control over suppliers, manufacturers, products, services, site conditions and workmanship to produce work of specified quality. 3. Required testing and inspection are intended to assist in determination of probable compliances of the work with the Contract Documents but do not relieve Contractor or Subcontractor of responsibility for those compliances. Specified testing and inspection are not intended to limit Contractor's quality control program. SECTION 01040 - SAFETY 1. Contractor shall take all necessary precautions for the safety of persons and the protection of the work and adjoining property. Contractor shall comply with all applicable provisions of federal, state and local safety 18Wb dttd buildi;4 codas. 2. Contractor shall erect and properly maintain at all times, as required by conditions and the progress of the work, all necessary safeguards for the protection of the employees of Contractor, his subcontractors, Owner and its lessee, Owner's other contractors, members of the public and for the protection of the work and adjoining property. 3. All workmanship shall comply with the Occupational Safety and Health Administration Standards. SECTION 01340 - SHOP DRAWINGS AND SAMPLES 1. Submit all drawings, diagrams, illustrations, schedules, performance charts, instructions, specifications and other project data illustrating portions of the work as required by the specification sections. Such submittals, whether or not referred to as shop drawings herein prescribed. Unless otherwise noted in the specification sections, submit a minimum of five (5) sets of shop drawings to Project Engineer. Two (2) sets will be returned to Contractor unless otherwise requested. 2. Do not commence any portion of the work requiring a shop drawing or sample submittal until the submittal has been approved as prescribed herein. All such portions of the work shall be in accordance with approved shop drawings or samples. SECTION 02110 - SITE CLEARING 1. Scope of Work Clearing and grubbing shall consist of cutting, removal and satisfactory disposal of all trees, down timber, brush, projecting roots, stumps, rubbish, boulders, broken concrete, fencing (as designated), and other material on the project site as indicated on the Site Demolition Plan. 2. All debris generated from the clearing operations stated in Item i shall be removed and legally disposed of off the project site; unless a "Bury- Pit ", approved by the Construction Manager and Developer, can be utilized in an area where it shall not be beneath building areas and /or pavement areas and shall not be located in an area where any utility structures are located or where impoundment of surface drainage may occur. 3. Materials shall not be disposed of by burning unless approved by the local Fire Marshall and the Construction Manager, and all required permits are obtained by the Contractor. 4. Traffic: Conduct site clearing operations to ensure minimum interference with roads, streets, walks, and other adjacent occupied or used facilities. Do not close or obstruct streets, walks or other occupied or used facilities without permission from the appropriate governmental agency, see Traffic Control Plan. 5. Protection of Existing Improvement: Provide protections necessary to prevent damage to existing improvements indicated to remain in place. a. Protect improvements on adjoining properties and on Owner's property. b. Restore damaged improvements to their original conditions, as acceptable to parties having jurisdiction. 6. Protection of Existing Trees and Vegetation: Protect existing trees and other vegetation indicated to remain inplace, against unnecessary cutting, breaking or skinning of roots, skinning and bruising of bark, smothering of trees by stockpiling construction materials within drip line, excess foot or vehicular traffic, or parking of vehicles within drip line. Provide temporary guards to protect trees and vegetation to be left standing. 7. All trash and lose debris is to be picked up and disposed of at least once a week. Outfoll structure of proposed lake is to be kept free o! ,. ^�! ±rash. SECTION 02210 - STRIPPING 1. The Contractor shall remove all topsoil in the areas to be occupied by roads, parking areas, walks buildings and designated future building fill areas. Topsoil shall be removed to a depth of six (6) inches or deeper, if necessary, to remove vegetative matter where required. if site has been recently stripped, the topsoil shall be removed to depth required to remove all roots as required by engineer or testing lab. 2. Topsoil shall be kept separated from suitable fill materials and shall not be used as fill under pavement and building areas. 3. Topsoil shall be stored at a location where it does not interfere with construction operations. 4. Topsoil shall be reasonably free from subsoil debris, stones, etc. 5. Topsoil shall be spread over all areas to receive seeding and landscaping. Landscaped islands and planting area shall have a minimum of 12 inches of topsoil and seeded or sodded areas shall have a minimum of 6 inches of topsoil spread. 6. Excess topsoil to be stockpiled in the areas designated on the grading plan, or removed from the site if directed by the owner or engineer. SECTION 02220 - EARTHWORK Scope of Work Extent: The work required under this section consists of all common rvorlon, fillinrj, rrlltth Vidinfl, backfilling and riIlfl!ed iltfflF -; necessary to complete the work indicated on the drawings and d described in the specifications. 1. In general, the items of work to be performed under this section shall include: fill compaction and rough and finish grading of entire site as indicated on the drawings including subgrade preparation and grading for streets, building pods, parking lots, walks and general cut and fill. 2. Fill material: shall consist of earth obtained from cut areas, borrow pits or other off -site sources. Earth shall be free from vegetable matter and other deleterious substances and large rocks. Fill obtained from off -site shall be of kind and quality as specified for fills and the source shall be approved by the owner. The fill material shall be placed in layers not to exceed six inches following compaction. Moisture content of fill material will be such that compaction to specified density is possible. All fill beneath paved areas, floor slabs and future buildings shall be compacted to at least 95% of the modified Proctor maximum dry density (ASTM -D -1557) or higher if recommended by Soils Engineer See soil boring report by Dated----------- - - - - -- 3. Excavate, replace and dispose of site soil materials determined to be unsuitable by Project Engineer or Soils Engineer if Engineer so directs. 4. Replace unsuitable soil materials with Common Fill Materials specified and backfill, compact and grade the replacement materials as specified herein. 5. Dispose of unsuitable soil materials on site in the area designated by Engineer and seed as noted. Bury pits can be utilized in nonstructural fill area not restricted by other easements to obtain suitable fill material and waste unsuitable soil and unused topsoil. 6. Contractor will be compensated for excavation, replacement and disposal of unsuitable soil materials for soil other than noted on plans based on the volume of excavation, time and the contract unit price of the specified fill. 7. Perform earthwork operations to establish required elevations and dimensions within the following tolerances, except that no tolerance will be permitted that would allow a lesser size than indicated for footings and foundations or a lesser thickness than indicated for paving, paving base courses and concrete floor slabs -on- grade. A. Under buildings and paving areas & swales: + 0.10 feet. B. Other Areas: + 0.20 feet. 8. Place topsoil to minimum depths indicated on the planting plans in each respective area. Place topsoil in 6" compacted lifts and develop smooth planting surfaces. Subgrade shall be scarified 3" to 6" in depth before topsoil is spread. Remove all vegetation, stones, roots and rubbish from topsoil and rake to even surface. Carefully spread topsoil to meet walks, paving, adjacent properties, and be free of low spots. Finish grade shall be + 1" of finish grade elevations shown on the grading plan. 9. Settling: Where settling is measurable or observable at excavated areas during general project warranty period, remove surface (pavement, lawn or other finish), add backfill material, compact, and replace surface treatment. Restore appearance, quality, and condition of surface or finish to match adjacent work, and eliminate evidence of restoration to greatest extent possible. 10. Removal from Owner's Property. Remove waste materials, including surplus excavated material, unacceptable excavated material, trash and debris, topsoil, and legally dispose of it off project site unless otherwise directed. The location of dump and length of haul shall be the Contractor's responsibility. SECTION 02510 - STREETS AND PARKING LOTS I. Scope of Work The work required under this section includes all concrete and bilufliintlut pflvirltl and 1pinitttl it rfi flecessary is complete the work indicated on drawings and described in the specifications, including but not limited to: All streets, parking areas in contract limits Curbs and gutters Signs, concrete slabs 2. Concrete: Plain concrete pavements shall be constructed in accordance with Section 501 of the Indiana Dept. of Transportation Specifications. Concrete shall be ready -mixed concrete and shall be a mix of proportioned fine and coarse aggregates with Portland cement and water. Minimum cement content shall be 6 bags per cubic yard of concrete and maximum water content shall be 5.5 U.S. gallons per sock of cement, including moisture in the aggregate. Slump for normal weight concrete shall be a maximum of 4 inches and a minimum of 2 inches. The slump of machine ~)laced concrete shall be no less than 1 -1/4 inches nor more than 3 inches. Standard test ASTM C -143 shall be used to measure slump. Compressive strength of concrete at 28 days shall be 4000 psi. All exterior concrete shall have air entrainment of 5% to 8% by volume per ASTM C -260. Retempering of delivered concrete will not be allowed. Concrete shall be composed of: A. Portland Cement: Conforming to ASTM C -150, Type IA or Type IIIA. B. Aggregates: Conforming to ASTM C -33. C. Water: Shall be clear and free from injurious amounts of oils, acids, alkalies, organic materials or other deleterious substances. 3. Welded Steel Wire Fabric: Where required for concrete reinforcement shall conform to ASTM A185. 4. Premoulded Joint Filler: Shall be of non - extruding type meeting ASTM D -544, except that premoulded joint filler used in concrete walk construction may be either non - extruding or resilient. 5. Bituminous Pavement Materials: All materials proposed for the construction of bituminous pavements shall comply with the Indiana Department of Highways Specifications, per latest revisions (Section 402) 6. Compacted Aggregate Subbase: Shall be crushed stone or gravel. Crushed gravel shall be a minimum of 35% crushed material. Chert shall be lim;,ed to a maximum of 8% of the total. Material shall be free from an excess of flat, elongated, thinly laminated, soft a disintegrated pieces; and shall be free from fraoments coated with dirt. Compacted aggregates be graded as follows: SIEVE SIZE % PASSING 1 -1/2 "- 100 1 80 -100 3/4° 70 -90 1/2" 55 -80 #4 35 -60 N8 25-50 #30 12 -30 #200 5 -10 7. Tack and Prime Coats: To assure bond between base and binder courses or between binder and surface courses, apply complete tack and prime coating. Place binder and /or surface course immediately after opplying tack or prime coat after specified drying time. A. Apply tack coat to contact surfaces of previously constructed asphalt or portland cement concrete and surfaces abutting or projecting into asphalt concrete pavement. Distribute at rate of 0.05 to 0.15 gallon per square yard of surface. Cut -back asphalt type: AASHTO M 82 (ASTM D 2027) MC -30, MC -700, MC -250. B. Apply prime coat over compacted base stone. Apply material to penetrate and seal, but not flood, surface. Cure and dry as long as necessary to attain penetration and evaporation of volatile. Distribute at a rate of 0.2 to 0.5 gallon per square yard. Emulsified asphalt; AASHTO M140 (ASTM D 997) or M208 (D 2397); SS -I, SS -1H, CSS -1 diluted with one part water to one part emulsified asphalt. 8. Striping Materials: Traffic paint, white, chlorinated rubber base, factory mixed, quick drying, non - bleeding: conforming to Fed. Spec. TT- 0 -115C, Type II and conforming to ISHSS Section 908. 9. Grading: Do any necessary grading to that performed in accordance with Earthwork Section, to bring subgrades, after final compaction, to the required grades and sections for site improvement. 10. Preparation of Subgrade: Remove spongy and otherwise unsuitable material and replace with stable material. No traffic will be allowed on prepared subgrade prior to paving. 11. Compaction of Subgrade: The first 6 inches below the subgrade shall be compacted to at least 95% of the maximum dry density as determined by the provisions of AASHTO T -99. Water shall be prevented from standing on the compacted subgrade. Clay and silty clay soil shall be compacted at a moisture content 1% to 2% above optimum moisture to reduce future volume changes. All testing shall be performed by a qualified Soils Engineer. 12. Acceptance of Subgrade: The placing of the stone base constitutes that the paving contractor has accepted the condition of the subgrade and accepts full responsibility for maintaining the grade elevations and contours indicated on the Drawings. Subgrade shall be inspected and tested by the appropriate governmental agency prior to pavement construction. Should the paving contractor refuse acceptance of the subgrade, he shall notify the General Contractor immediately of the deficiencies. Should the paving contractor fail to notify the General Contractor of any deficiencies and /or proceed in the placing of the stone base, said actions shall constitute acceptance of subgrade. 13. Utility Structures: Check for correct elevation of all manhole covers, valve boxes and similar structures located within areas 10 be paved, and make, or har made, any necessary adjustments ih such ,. tructures. 14. Placing Concrete: A. Subgrade: Place concrete only on a moist, compacted subgrade or base free from loose material. Place no concrete on a muddy or frozen subgrade. B. Forms: All forms shall be free from warp, tight enough to prevent leakage and substantial enough to maintain their shape and position without springing or settling, when concrete is placed. Forms shall be clean and smooth immediately before concreting. C. Placing Concrete: Concrete sholl be deposited so as to require as little rehandling as practicable. When concrete is to be placed at an atmospheric temperature of 35 degrees F. or less, paragraph 702.10 of the Indiana Department of Highways Specifications, latest revision shall be followed. 15. Concrete Curb and Gutter: A. Expansion Joints: Shall be 112 inch thick premoulded at ends of all returns and at a maximum spacing of 100 feet and at all inlets. B. Contraction Joints: Unless otherwise provided, contraction joints shall be sawed joints spaced 10 feet on center and 5' on all curved radii.. C. Finish: Tamp and screed concrete as soon as placed, and fill any honey combed place. Finish square corners to 1/4 inch radius and other corners to radii shown. D. To prevent underming by water, curbs shall be promptly and carefully backfilled after application of curing protection, which shall take place immediately after the slip forming or removal of forms. Curing shall meet Section 501.17(e) of the Standard Specifications. Backfill shall be compacted as soon as practical and maintained at an elevation slightly below the curbs (max. 1 "). As the backfill settles, it shall be regraded as often as necessary to keep it slightly below the curb. 16. Concrete Walks and Exterior Steps conforming to Section 604 of the Indiana Dept. of Highways Specifications. A. Slopes: Provide 1/4 inch per foot cross slope. Make adjustments in slopes at walk intersections as necessary to provide proper drainage. B. Dimensions: Walks and steps shall be one course construction and of widths and details shown on the drawings. 17. Bituminous Pavement: Hot asphalt concrete pavement shall be as specified in Section 402 of the Indiana Department of Transportation Specifications, latest revisions. Paving will not be permitted during unfavorable weather or when the temperature is 40 degrees F. and falling. 18. Compacted Aggregate Subbase: The thickness shown on the drawings is the minimum thickness of the fully compacted subbase. Compaction shall be accomplished by rolling with a smooth wheeled roller weighing 8 to 10 tons. Compact to 100% of maximum dry density in accordance with Section 304.05. Along curbs, headers and walls and at all places not accessible to the roller, the aggregate material shall be tamped with mechanical tampers or with approved hand tampers. 19. Construction within Right -of -Way. All street construction within the lines of dedicated right -of -way shall be in accordance with the Specifications of the Hamilton County Highway Dept. 20. Pavements built by stage construction, that is pavements used to carry traffic before the full pavement structure is in place, will have each stage used by traffic inspected by the Hamilton County Highway Dept., for distressed areas before the next stage is started. Distressed areas will be repaired to the satisfaction of the Hamilton County Highway Dept. before an additional stage is constructed. 21. Street Signs: Street name signs shall be furnished at the developer's expense and installed prior to the release of the performance bond or prior to the issuance of the first occupancy permit, whichever occurs first. The signs shall be installed on one post at each street intersection at an appropriate spot in the northeast corner wherever possible. Signs and posts shall be standard sizes and colors on reflective surfaces. 22. Regulatory and Warning Signs: Regulatory and warning signs shall be furninshed at the developers expense and installed by the Hamilton County Highway Dept. in conformity with the Indiana Manual on Uniform Traffic Control Devices. The signs shall be delivered prior to the release of the performance bond or prior to the issuance of the first occupance permit, whichever occurs first. Signs and posts shall be standard sizes and colors on reflective surfaces. SECTION 02620 - UTILITIES (Gas, Electric, Telephone and T.V.) 1. Utilities: It shall be the responsibility of each contractor to verify all existing utilities and conditions pertaining to his phase of work. It shall also be the caflfrat tuf s Iesponsiblhty to cotiltict 4fie ownefs of the various utilities before work is started. The contractor shall notify in writing the owners or the Engineer of any changes, errors or omissions found on these plans or in the field before work is started or resumed. 2. If active utilities are encountered but not shown on the drawings, the Engineer and utility representative shall be advised before work is continued. 3. Inactive and abandoned utilities encountered in excavating and grading operations shall be reported to the Engineer and utility company. They shall be removed, plugged or capped as directed by the utility company and Engineer. 4. Rules and regulations governing the respective utilities shall be observed in executing all work under this section. 5. Granular backfill shall be required for all utility crossings under pavement areas except for utilities which are bored or pushed under street. 6. Conduit shall be required for all crossings under pavement areas. Contractor shall coordinate with each respective utility for their location and installation. Conduit shall be 4" PVC Schedule 20 or approved equal. 7. Existing storm sewers, sanitary sewers, water mains, gas mains, electric ducts, telephone ducts, steam mains and other underground structures have been shown on the plans according to the best available information. The exact location and protection of these facilities and structures, their support and maintenance in operation during construction (in cooperation with the proper authorities of the utility involved), is the express responsibility of the Contractor in the performance of his contract and in the preparation of his bid. 8. All electrical light posts must be set back in the designated utility easement as shown in the construction plans. Any lights which are installed within the dedicated right of way shall be removed and /or relocated at the Developer's expense. SECTION 02720 - STORM SEWERS 1. Scope of Work The work under this section includes all storm sewers, storm wolf 11hi`s, and i ldIe-d hff �, inAdirl O'1!,�Uhh fi N � J d backfilling, necessary to complete the work shown on the drawings. 21 Standard specifications of Indiana Department of Transporation shall apply for all work and materials. Pipe shall be installed in in accordance with Section 715. 3. All storm sewer pipe shall be reinforced concrete pipe conforming to ASTM Designation C -76 Class III, unless otherwise noted, in accordance with Section 906. Joints shall conform to ASTM C -433 latest revision. A.A.S.H.T.O. M 294 TYPE S (PIPES 12" - 36 ") A.S.T.M. D 3350 PIPES & FITTINGS A.S.T.M. D 2321 INSTALLATION A.A.S.H.T.O. T 99 BACKFILL (6" LIFTS W/95% COMPACTION) 4. Subdroinage system shall be installed as shown on plans and be of pipes designated in Section 907 of Indiana Dept. of Transportation specifictions as follows: Pipes to be installed for subsurface drainage only shall be the following: Perforated Corrugated drainage pipe in accordance with AASHTO M252 or AASHTO M 294. PVC shall have minimum cell classification conforming to requirement of 12344 -C ASTM D -1784. Where pipe is to be used for a collector of other subsurface laterals and /or sump pumps and installed with provisions for cleaning, it may be one of the following: A. ABS Composite in accordance with ASTM D -2680. B. PVC in accordance with ASTM D -3034 SDR -35, C. PVC Corrugated with smooth interior in accordance with ASTM F949. 5. Backfill around all structures and cuts under paved areas and within 5 feet of pavement edges with granular material in accordance with Section 211. Select Granular Fill - Well graded sand and gravel or crushed stone that has a uniformity coefficient (ASTM D -2487) of aggregates and contains less than 5 percent (by weight) fines passing a No. 200 Sieve size. Onsite excavated granular materials may be utilized if approved by the Soils Engineer. 6. See storm detail sheet for construction dimensions of storm structures. Manholes, inlets and catch basins shall be in accordance with Section 720. Precast concrete and steel for manholes and inlets shall be in accordance with ASTM C -478, latest revision. Steps shall be ductile iron or aluminum integrally cast into catch basin sidewalis. 7. The Contractor shall provide a minimum of 2' of cover over all storm sewers. Contact engineer if problems are encountered. 8. Rip rap shall be a minimum 6" and a maximum of 17" in size and a minimum 18" in depth. Dimensions for rip rap on this plan are for estimating purposes only Actual best placement of rip rap shall he determined by field conditions and shall be in accordance with Section 616. 9. All drainage pipe and ditch outfolls to receiving streams shall be constructed in accordance with drawings, subject however, to any modification required by Engineer at the time installation is completed and to any adjustments needed for field conditions not adequately anticipated by the design drawings. 10. Castings shall be as shown on storm detail sheet for manufacturer, type and number. All castings shall be Neenah or East Jordan or approved equal. Castings shall be gray iron meeting ASTM A -48, latest revision. 11. Install gaskets in accordance with manufacturer's recommendations for use of lubricants, cements and other special installation requirements. 12. Place plugs in ends of incomplete piping at end of work day or whenever work stops, and at stubs for future development. 13. Carry depth of trenches for piping to establish indicated flow lines and invert elevations. Notch under pipe bells where applicable to provide solid bearing for entire body of pipe. 14. Trenching: Lay all pipe in open trenches, except when the local authority gives written permission for tunneling. Open the trench sufficiently ahead of pipe - laying to reveal any obstructions. The width of the trench shall be the outside pipe diameter plus 6 inches each side for 12 inches above the pipe. Sheet and brace trench as necessary to protect workmen and adjacent structures. All trenching to comply with Occupational Safety and Health Administration Standards. Keep trenches free from water while construction is in progress. Under no circumstances lay pipe or appurtenances in standing water. Conduct the discharge from trench dewatering to drains or notrual drainage channels. 15. Backfilling: For a depth of at least 12 inches above the top of the pipe, backfill with earth or granular material free from large stones, rock fragments, roots or sod. Tomp this backfill thoroughly, taking care not to disturb the pipe. For the remaining trench depth, backfill with earth or granular motoerial containing stones or rocks not larger than 4 inches. Backfill under walks, parking areas, driveways and streets shall be granular material only -- thoroughly compacted, by approved methods. Trenches parallel to and within 5 feet of paved roadways shall be constructed the some. 16. Manhole Inverts: Construct manhole flow channels of concrete, sewer pipe or brick, smoothly finished and of semi - circular section conforming to the inside diameter of the connecting sewers. Make changes in size or grade gradually and changes in direction by true curves. Provide such channels for all connecting sewers at each manhole. 17. Shop drawings of all drainage structures shall be submitted to the Engineer per Section 01340.