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HomeMy WebLinkAbout31-2200-Earthwork_Rev_131 2200 - Earthwork Page 1 of 24 Dennis Yarmouth Intermediate Middle School January 19, 2021 Dennis Yarmouth Regional School District 100% Construction Documents Perkins Eastman DPC, Project No. 71011 31 2200 - EARTHWORK PART 1 - GENERAL 1.01 DESCRIPTION A. Drawings and general provisions of Contract, including General and Supplementary Conditions and Division 1 Specification Sections, apply to this Section. B. Provide all facilities, labor, materials, tools, equipment, appliances, transportation, supervision, and related work necessary to complete the work specified in this section, and as shown on the Drawings. C. The work of this section includes but is not necessarily limited to: 1. Excavation of encountered site soil material including: topsoil, loose silty and sandy glacial fluvial soil as well as any other found unsuitable soil. a. Although less likely on this site: removal of large boulders, buried concrete, pavements, utilities, building debris, and b. To provide materials required to construct the proposed building foundations, slabs, structures, utilities, roadways, parking areas, detention basins, and other site developments shown on the Drawings. c. The required excavation shall include the removal of all unsuitable soils from within the zone of influence of proposed foundations, utilities, structures, and below paved areas and other site developments. 2. Providing, placement, moisture conditioning, compaction, and grading of all required fill and backfill materials to the required horizontal and vertical limits and percent compaction that is required to construct proposed foundations, slabs, structures, utilities, roadways, parking areas, detention basins, and other site developments shown on the Drawings. 4. Excavation, fill, and backfill, as indicated or required, including compaction. 5. Excavation, as required, to the lines and grades indicated on the Drawings. 6. Removal from the site and legal disposal of excess materials or materials that are not suitable for on-site re-use. 7. Rough grading, including placement, moisture conditioning and compaction of fills and backfills. 8. Base and subbase course materials under structures, pavements, slabs and footings, including compaction. 9. Trench excavation, bedding and backfill for all structures, foundations, and utilities, including compaction. 10. The removal, hauling and stockpiling of suitable excavated materials for subsequent use in the work. 31 2200 - Earthwork Page 2 of 24 11. All rehandling, hauling and placing of stockpiled materials for use in refilling, filling, backfilling, grading and such other operations. 12. Protection of existing buildings, pavements, and utilities to remain. 13. Furnishing and installing all sheeting, shoring, and bracing of structural and trench excavations. All excavations, including all sheeting, shoring, and bracing, shall be made in accordance with OSHA requirements and other applicable laws and regulations. 14. Environmental controls. 15. Rip-rap. 16. Obtain and pay for all required permits, licenses, and approvals of appropriate municipal and utility authorities, prior to commencing the work of this Section, and pay all costs incurred therefrom. 17. Controlling intruding surface water and groundwater providing construction dewatering. 1.02 RELATED SECTIONS A. Carefully examine all of the Contract Documents for requirements which affect the work in this section. Other specifications sections which directly relate to the work of this section include, but are not limited to, the following: 1. Section 02270 - Erosion Control 2. Section 02400 - Storm Drainage System 3. Section 02513 - Bituminous Concrete Pavement 4. Section 02400 - Storm Drainage System 5. Section 02570 - Sanitary Sewage System 6. Section 02800 - Seeding 1.03 REFERENCE STANDARDS A. Reference herein to any technical society, organization, group or body are made in accordance with the following abbreviations and, unless otherwise noted or specified, all work under this Section shall conform to the latest edition as applicable: 1. ASTM: American Society for Testing and Materials 2. ANSI: American National Standards Institute 3. OSHA: Occupational Safety and Health Administration 4. AGCA: Associated General Contractors of America, Inc. 5. AASHTO: American Association of State Highway Transportation Officials B. Applicable specifications of the American Society for Testing and Materials (ASTM). 1. D422 Method for Particle Size Analysis of Soils. 2. D698 Test for Moisture-Density Relations of Soils Using 5.5 lb. (2.5 Kg) Rammer and 12-inch (304.8 mm) Drop (Standard Proctor). 3. D1556 Test Method for Density of Soil in Place by the Sand Cone Method. 4. D1557 Test methods for moisture-density relations of soils and soil aggregate mixtures using 10 lb. hammer and 18-inch drop. 5. D2167 Test for Density of Soil in Place by the Rubber Balloon Method. 31 2200 - Earthwork Page 3 of 24 6. D2216 Laboratory Determination of Water Moisture Content of Soil, Rock, and Soil Aggregate Mixtures. 7. D2487 Classification of Soils for Engineering Purposes 8. D2922 Test methods for density of soil and soil- aggregate in place by nuclear methods (shallow depth). 9. D3017 Test for Moisture Content of Soil and Soil-Aggregate in Place by Nuclear Methods (Shallow Depth). 10. D4318 Test for Plastic Limit, Liquid Limit, and Plasticity Index of Soils. 1.04 LAWS AND REGULATIONS A. All work shall be accomplished in accordance with regulations of local, county and commonwealth agencies and national or utility company standards as they apply. 1.05 QUALITY ASSURANCE A. The Owner will retain a Geotechnical Engineer or Testing Agency to perform on-site observation and testing during the following phases of the construction operations. The services of the Geotechnical Engineer or Testing Agency may include but are not necessarily limited to the following: 1. Observation during excavation and dewatering of construction areas, building subgrade areas, roadway areas, and controlled fill areas. 2. Observation during placement and compaction of fills within the roadway area, building subgrade areas, and other controlled fill areas as appropriate. 3. Laboratory testing and analysis of fill and bedding materials specified, as required. Note this laboratory testing is typically provided by a source pit’s documented recent testing or by a Testing Agency. 4. Observation of construction and performance of water content, gradation, and compaction tests at a frequency and at locations determined by the Geotechnical Engineer or Testing Agency in consultation with the site General Contractor’s representative. a. The results of these tests will be submitted to the Contractor and Architect, on a timely basis so that the Contractor can take such action as is required to remedy indicated deficiencies. b. During the course of construction, the Geotechnical Engineer or Testing Agency will advise the Architect in writing with copy to Contractor if, at any time, in his opinion, the work is not in substantial conformity with the Contract Documents. 5. Observation of excavated materials for assessing reuse or other disposition. B. The Geotechnical Engineer's or Testing Agency’s presence does not include supervision or direction of the actual work by the Contractor, his employees or agents. Neither the presence of the Geotechnical Engineer or Testing Agency, nor any observations and testing performed by him, nor any notice of failure to give notice shall excuse the Contractor from defects discovered in his work. C. The Owner reserves the right to modify or waive Geotechnical Engineer or Testing Agency services. 31 2200 - Earthwork Page 4 of 24 D. All costs related to retesting due to failures shall be paid for by the Contractor at no additional expense to Owner, and the costs thereof will be deducted by the Owner from the Contract Sum. E. The Contractor shall not place any fill or prepare any subgrade unless the Geotechnical Engineer or Testing Agency is present. The Contractor shall keep the Geotechnical Engineer or Testing Agency informed of planned work activities to allow the Geotechnical Engineer or Testing Agency sufficient time to arrive on-site. 1.06 SAMPLES AND TESTING A. All fill materials and their placement shall be subject to quality control testing. A qualified testing laboratory will be selected and paid by the Owner to perform tests on materials. Test results and laboratory recommendations will be available to the Contractor. B. The Contractor shall be responsible for obtaining test samples of fill materials proposed to be used and transporting them to the site sufficiently in advance of time planned for use of these materials for testing of materials to be completed. Use of the proposed materials by the Contractor prior to testing and approval (or rejection), shall be at the Contractor's risk. C. The Geotechnical Engineer will be the sole and final judge of the suitability of all materials. D. The Geotechnical Engineer or Testing Agency will determine from laboratory test results the maximum dry density and optimum water content in accordance with ASTM D1557, Method D for a given material, and its on-site in-place density in accordance with ASTM D1556, or D2922 and D3017. E. Tests of a material as delivered may be made from time to time to insure consistency with the initial submittal tests. Materials found questionable may not be used, pending updated test results. Tests of compacted materials will be made regularly. Rejected materials should be removed from the site. F. The Contractor should cooperate with the soils testing laboratory in obtaining field samples of in-place materials after compaction. The Contractor should furnish incidental field labor in connection with these tests. G. When initial tests indicate non-compliance with the specification, subsequent retesting occasioned by the non-compliance shall be performed by the same testing laboratory, and the costs thereof will be deducted by the Owner from the Contract Sum. 1.07 SUBMITTALS A. At least ten (10) days prior to mobilizing to the site, the Contractor shall submit the following: 1. Proposed schedule, sequence and procedures for all earthwork operations. Proposed earthwork sequencing and procedures shall include detailed descriptions of all methods, operations and equipment proposed for excavation, subgrade preparation, backfilling, surface water control, and construction dewatering. 31 2200 - Earthwork Page 5 of 24 2. Details of compaction equipment, including descriptions, product literature, specifications and ratings, proposed for use in compacting fill and backfill materials. B. Submit a covered, ¾ full, 5-gallon bucket sample of each type of off-site fill material that is to be used at the site to the testing laboratory, a minimum of one week prior to delivery to the site. Alternately, material source laboratory testing may be accepted if approved by the Geotechnical Engineer. As materials are brought on-site following initial submittal testing and acceptance, additional samples shall be provided, as requested by the Geotechnical Engineer, to evaluate the consistency of the source or process, at no additional cost to the Owner. C. Submit the name of each material supplier and specific type and source of each material. Any change in source throughout the job requires approval of the Architect or Geotechnical Engineer. D. For use of fabrics or geogrids, submit manufacturer's literature and a sample for approval by the Geotechnical Engineer or Architect. E. Prior to delivery to the site, submit chemical test data and source site data on fill materials being imported to the site to the Architect. All materials being imported to the site shall be free of contamination, oil and hazardous materials. Submit documentation that confirms that all imported materials are free of contamination and are below Reportable Concentrations as defined by the Massachusetts Contingency Plan or other statute. 1. Source site data shall include: a. Location, owner and nature of source site. b. Present and past source site usage c. Any site assessment reports prepared for the source site relating to the presence of oil or hazardous materials F. If directed by the Architect due to the nature of the material or its source, the Contractor shall conduct testing on proposed fill material and submit results prior to delivery to the site, at no additional cost to the Owner: 1. Chemical test data, if requested by the Architect, shall include: a. Total Petroleum Hydrocarbons (EPA Method 418.1) every 100 yards b. Volatile Organic Compounds (EPA Method 8240) every 500 yards c. PCB and Pesticides (EPA Method 8080) every 500 yards d. Total RCRA Metals (EPA Method 6000-7000 series) every 500 yards e. Polynuclear Aromatic Hydrocarbons (EPA Method 8270) every 500 yards f. TCLP for those total parameters which exceed twenty times the TCLP criteria every 500 yards. Testing shall be conducted by a testing laboratory certified in the Commonwealth of Massachusetts. G. Submittal requirements related to construction dewatering and drainage control shall be made to the Architect prior to construction. 31 2200 - Earthwork Page 6 of 24 1.08 DISTURBANCE OF EXCAVATED AND FILLED AREAS DURING CONSTRUCTION A. The Contractor shall take the necessary steps to avoid disturbance of subgrade and underlying natural soils/compacted fill during excavation and filling operations. Methods of excavation and filling operations shall be revised as necessary to avoid disturbance of subgrade and underlying soils/fill, including restricting the use of certain types of construction equipment and their movement over sensitive or unstable materials, dewatering, and other acceptable control measures. Disturbance shall be construed to include deterioration of fill (after placement and satisfactory compaction) due to the Contractor's operations, such as moving equipment, hauling trucks, etc. The Contractor shall cooperate with the Architect or Geotechnical Engineer to modify his operations as necessary to minimize disturbance and protect bearing soils, based on the Architect's or Geotechnical Engineer's recommendations. B. All excavated or filled areas disturbed during construction, all loose or saturated soil, and other areas that will not meet compaction requirements as specified herein shall be removed and replaced with Compacted Structural Fill. Fill that cannot be compacted within 48 hours because of its saturated condition shall be removed and replaced with Compacted Structural Fill. Costs of removal of disturbed material and recompaction with Compacted Structural Fill shall be borne by the Contractor. 1.09 COORDINATION A. Prior to start of earthwork the Contractor shall arrange an on-site meeting with the Architect and Geotechnical Engineer or Testing Agency for the purpose of establishing the Contractor's schedule of operations and scheduling inspection procedures and requirements. B. As construction proceeds, the Contractor shall be responsible for notifying the Architect and Geotechnical Engineer or Testing Agency prior to the start of earthwork operations requiring inspection and/or testing. 1.10 SUBSURFACE SOIL DATA AND EXISTING CONDITIONS A. The Contractor should review logs of borings, reports of explorations and other pertinent data for the site. After obtaining Owner's permission, take whatever additional subsurface explorations deemed necessary at no expense to the Owner. Any test pit explorations should avoid disturbance of future building’s structural bearing soils. B. A geotechnical engineering report specific to this site was prepared by Geotechnical Partnership, Inc. of Swampscott, MA entitled “Design Phase Geotechnical Report Proposed Dennis Yarmouth Intermediate School 296 Station Avenue South Yarmouth, Massachusetts (18 February 2020). It is included in the Project Documents. 1.11 LINES, GRADES AND TOLERANCE A. The Contractor shall be responsible for establishing all lines, grades, and other survey control to complete the Work. B. Construct finished soil, and backfill surfaces to plus or minus ½-inch of the elevations indicated on the Drawings. C. Maintain the moisture content of fill material as it is being placed within plus or minus two percent of the optimum moisture content of the material as determined by the laboratory tests specified herein. 31 2200 - Earthwork Page 7 of 24 D. Where not shown otherwise on the Drawings or criteria given in the specifications, grades at the perimeter of excavated areas shall be gradually transitioned into existing grades. PART 2 - PRODUCTS 2.01 MATERIAL CLASSIFICATION A. On-Site Fill 1. Limited granular fill should be expected at surface below any included former paved site areas to less than 1 ft. +/- in thickness. This material where found may be acceptable for re-use on-site as engineered fill pending laboratory gradation testing. 2. Common (silt loam) fill soil materials are present on-site near surface, in general site areas. They are encountered directly above the native sandy glacial soil deposits to up to 3.5 ft.+/- in found thickness. 3. Although, not found in the borings, The common fill may contain variable quantities of soil, cobbles, boulders and other materials which have not been systematically screened or segregated. 4. The on-site common fill may be acceptable for use as Common Fill/Ordinary Fill provided oversized boulders, bedrock, blast rock, brush, organic soils, debris, trash, solid waste and other deleterious materials are removed and the material is placed and compacted as required herein as Common Fill/Ordinary Fill, and forms a firm, stable subgrade and fill without weaving and instability, as judged by the Geotechnical Engineer or Testing Agency. B. On-Site Native Soils 1. Excavated native clean glacial fluvial sand soil and silty sand soil deposits may be stockpiled for potential reuse as Common Fill/Ordinary Fill outside the proposed building limits. Native sand with sufficient found gravel content may qualify for re-use as engineered fill. 2. During favorable, dry, warm weather, the native sand containing sufficient gravel content may be excavated and stockpiled for potential reuse as Compacted Granular Fill (see geotechnical site review, page 26), depending upon the results of associated laboratory soil particle gradation testing. 3. Moisture conditioning, particularly during wet weather periods, may be required to permit placement in thin lifts of native clean glacial fluvial sand to the required compaction. The placement and compaction of glacial fluvial soil materials below slabs must be observed and documented in the field by the Geotechnical Engineer or Testing Agency. 4. The following should be considered when evaluating the use of the on-site glacial fluvial sand with gravel for Compacted Granular Fill (see geotechnical site review, page 26),: a. Control moisture content of excavated glacial fluvial sand. Moisture conditioning by drying or adding water may be necessary. 31 2200 - Earthwork Page 8 of 24 b. Oversize stones (size greater than of the lift thickness) would have to be removed prior to placement. c. Placement and compaction of glacial fluvial sand must be completed when ambient air temperatures are above 32 degrees Fahrenheit. d. Compact and smooth-roll glacial fluvial sand fill, which is placed during the day, at the end of the work day. e. Remove any soils used which freeze overnight prior to placing additional fill. 5. Provide drainage from or cover stockpiles of glacial fluvial sand when not in use or during precipitation. C. Crushed Concrete (Recycled Concrete) 1. Crushed concrete demolition debris may also be used, or combined with other acceptable materials for use as Compacted Structural Fill, subject to acceptance of the Geotechnical Engineer. 2. Crushed concrete shall not be used where free-draining fill is required, directly beneath slabs or where subsequent excavations are required, unless specifically approved by the Geotechnical Engineer. 3. Use of crushed concrete during wet conditions as Compacted Structural Fill should be avoided due to difficulty in compaction. It becomes notably spongey. D. Common Fill/Ordinary Borrow 1. Common Fill/Ordinary Borrow shall consist of a material satisfactory to the Geotechnical Engineer and not specified as Gravel Borrow, Compacted Structural Fill, Compacted Granular Fill, Sand Borrow, or other particular kinds of fill or borrow. 2. This material shall be free from organic material, weak or compressible material, highly plastic clays, frozen and other unsuitable material. It shall have the properties such that it may be readily spread and compacted for raising grades in pavement, site and outside building areas, the formation of embankments and shall conform to the following: Sieve (ASTM D422) Percent Passing by Weight 6-inch 100 No. 40 15-80 No. 200 0-40 3. If Common Fill/Ordinary Borrow is placed as backfill material in trenches outside building areas, near utilities, or within 2 feet of foundation walls (outside the building), the largest particle dimension shall be 3 inches. 4. On-site excavated materials may be acceptable for use as Common Fill/Ordinary Borrow if debris particles larger than 6-inches and deleterious materials are removed, the material is judged by the Geotechnical Engineer or Testing Agency 31 2200 - Earthwork Page 9 of 24 to be compactible, and subject to the requirements discussed herein for each material. Special handling such as the use of screens may be required to segregate over-sized debris and miscellaneous deleterious materials. E. Gravel Borrow (Types B and C): Gravel Borrow shall consist of inert material that is hard, durable stone and coarse sand, free from loam, clay, surface coatings and deleterious materials. Gravel Borrow shall conform to the following gradation: Sieve Percent (ASTM D422) Passing ½-inch 50-85 No. 4 40-75 No. 50 8-28 No. 200 (ASTM D1140) 0-8 The maximum size of stone in gravel shall be: 3 inches (Type B) 2 inches (Type C) F. Sand Borrow (Types A and B): Sand Borrow shall consist of clean, inert, hard, durable grains of quartz or other hard, durable rock, free from loam or clay, surface coatings and deleterious materials. The allowable amount of material passing a No. 200 sieve as determined by AASHTO- T11 (ASTM D1140) shall not exceed 10 percent by weight. The maximum size for Sand Borrow Type A shall be ¼-inch. The maximum size for Sand Borrow Type B shall be determined by the Site Civil Engineer. G. Crushed Stone 1. Crushed Stone shall be composed of durable crushed rock consisting of angular fragments, free from a detrimental quantity of thin, flat, elongated pieces or other objectionable pieces; or durable crushed gravel stone obtained by artificial crushing of gravel boulders, fieldstone, or blast rock with a minimum diameter before crushing of 8 inches. The crushed stone shall be reasonably free from clay, loam or deleterious material and not more than 1.0 percent of satisfactory material passing a No. 200 sieve will be allowed to adhere to the stone. 2. Crushed Stone shall conform to the following gradations: Sieve Size Percent Passing By Weight ¾-Inch ½-Inch 1 inch 100 --- 3/4 inch 90-100 --- 5/8 inch --- 100 1/2 inch 10-50 85-100 3/8 inch 0-20 15-45 No. 4 0-5 --- No. 8 --- 0-5 31 2200 - Earthwork Page 10 of 24 Sieve Size Percent Passing By Weight 1-1/2-Inch 1-1/4-Inch 2 inch 100 --- 1-1/2 inch 95-100 100 1-1/4 inch --- 85-100 1 inch 35-70 --- 3/4 inch 0-25 10-40 1/2 inch --- 0-8 H. Loam Borrow 1. Loam Borrow materials shall conform to the requirements of M1.05.0 of the MHD Standard Specifications for Highway Bridges, 1988. 2. Topsoil stripped from the site: Topsoil stripped from the site and properly stockpiled prior to application may, upon the approval of the Architect, be used for preparation of areas to be seeded. It shall be free of large (two inches or greater) cobbles, roots, old sod, trash, wood, or other contaminants, and be friable consistency and suitable for plant growth. 3. Samples for testing will be taken in the field upon notification of source, and no topsoil may be placed without proper authorization by the Architect. 4. Samples shall be tested by a qualified soils lab approved by the Architect. 5. Testing must confirm that the loam, either obtained from the site or borrow off site, contains not less than 4 percent nor more than 20 percent organic matter as determined by the loss on ignition of oven-dried samples. Test samples shall be oven-dried to a constant weight at a temperature of 221 degrees F (+5) and certified test results shall be sent to the Architect by the laboratory for approval. I. Compacted Structural Fill 1. Compacted Structural Fill beneath footings and slabs shall consist of suitable off- site bank-run sand and gravel, free of organic material, snow, ice, or other unsuitable materials. Use of Recycled Concrete as Compacted Structural Fill in wet conditions should be avoided due to difficulty in compacting. Compacted Structural Fill should be well-graded within the following limits: Sieve Size Percent Finer by Weight 6 in. (or 2/3 lift thickness maximum) 100 No.4 30-90 No. 40 10-50 No. 200 0-10 Compacted Structural Fill shall be placed in lift thicknesses not exceeding 12 in. in loose measure, and should be compacted to a dry density of at least 95 percent of the maximum dry density as determined in accordance with ASTM Test Designation D 1557. Compaction equipment in open areas should consist of fully-loaded ten-wheel dump trucks or self-propelled vibratory rollers such as a BoMag BW-60S. In confined areas, hand-guided equipment such as a large vibratory plate 31 2200 - Earthwork Page 11 of 24 compactor should be used, the loose lift thickness should not exceed 9 in., and the maximum particle size should be reduced to 4 in. A minimum of four systematic passes of the specified compaction equipment should be used to compact each lift. J. Processed Rock Fill 1. Processed Rock Fill should consist of well-graded crushed rock processed so that its largest dimension does not exceed 1.5 inches. Processed Rock Fill shall be placed and compacted to the requirements for Compacted Structural Fill. K. Choke Stone 1. Choke stone shall have a max. rock size of 9 inches and shall have fifty percent (50%) finer than 1-1/2 inches and twenty-five percent (25%) finer than ¾ inches. L. Filter Fabric/Geotextiles 1. Geotextile Fabric may be used as directed by the Geotechnical Engineer or Site Civil Engineer to prevent soil intrusion into drains and/or assist in stabilizing soil subgrades to be laid on approved soil subgrades prior to placement of fill materials. Fabric shall consist of a non-woven, synthetic, chemically resistant, non-biodegradable fabric with a minimum weight of 6 ounces per square yard. 2. Filter Fabric shall be Mirafi 140N, manufactured by Mirafi, Inc., Charlotte, NC 28224, or approved equal. 3. Stabilization fabric shall be Mirafi 600X, manufactured by Mirafi, Inc., Charlotte, NC 28224, or approved equal. M. Riprap 1. Riprap for pipe ends/energy dissipaters shall be stone conforming to the requirements of M2.02.3 of the MHD Standard Specifications for Highway Bridges, 1988. Stone for pipe ends shall be sound, durable rock which is angular in shape. Rounded stones, boulders, sandstone, and similar stone or relatively thin slabs will not be acceptable. Each stone shall be a minimum of 18-inches and a maximum of 30-inches in size. The stones shall be so graded that when placed with each other, the entire mass will be compact. N. Gravel Filter Layer 1. Gravel Filter Layer material for pipe ends/energy dissipaters shall be crushed rock or crushed gravel, conforming to ASTM D448, Size Number 67 gradation, as follows: Percent Passing Sieve Size by Weight 3 inch 100 2 inch 95-100 1 inch 55-85 No. 4 27-52 No. 200 (based on the fraction 0-12 passing the No. 4) 31 2200 - Earthwork Page 12 of 24 O. Dense Graded Crushed Stone - Dense graded crushed stone shall conform to the following gradations: Sieve Size (ASTM D422) Percent Passing by Weight 2 inch 100 1-1/2 inch 70-100 3/4 inch 50-85 No. 4 30-55 No. 50 10-35 No. 100 8-24 No. 200 3-10 P. Impervious Soil borrow for detention basins shall conform to the general requirements of MHD M1.08.0. The material shall generally be silt-clay materials in accordance with AASHTO-M145, except A-2 soils shall contain more than 20 percent by weight passing the No. 200 sieve. The material shall be reasonably free of stumps, brush and stones larger than 3 inches. 2.02 USE OF MATERIALS A. On-Site Common Fill: Use of existing soil as Common Fill/Ordinary Borrow if suitable for reuse in accordance with these Specifications. B. On-Site Native Glacial Fluvial Sand: Use as Common Fill/Ordinary Borrow if suitable for reuse in accordance with these Specifications. Where sufficient gravel is present within the glacial fluvial sand soil matrix utilize as Granular Fill per geotechnical report page 26. C. Crushed Concrete: Use as Common Fill/Ordinary Borrow and/or Compacted Structural Fill (in dry conditions) if suitable for reuse in accordance with these Specifications. D. Common Fill/Ordinary Borrow: Use common fill and/or ordinary borrow for general site grading, as backfill, embankment fill in areas outside the building and pavement limits. Use common fill to raise grades to pavement subgrade level and in landscape areas. Fill material shall be free of stones larger than two (2) inches maximum dimensions when used in trenches or when backfilling within two (2) feet of a structure. E. Gravel Borrow (Type B): Use for backfill in utility trenches, as subbase materials under all pavement areas, and at other locations as shown on the construction details. Gravel Borrow (Type C): Use for embedment materials around water sewer and drainage pipe and foundations for sewer and drain structures. F. Sand Borrow: Use for conduit bedding. G. Crushed Stone: Use crushed stone as a filter material around perforated pipe, and as shown elsewhere on the Drawings. H. Loam Borrow: Use as fill in landscape and lawn areas, if off-site material is required. I. Compacted Structural Fill: Use Compacted Structural Fill in building areas such as beneath floor slabs, foundations, and in other soil bearing situations. Compacted Structural Fill shall also be used for backfill against interior building foundations and frost walls. 31 2200 - Earthwork Page 13 of 24 J. Blast Rock Fill: unlikely to be used on this site; descriptions provided for completeness 1. Blast Rock Fill Below Building Areas, consisting of on-site blast rock, may be reused as Compacted Granular Fill below footings and slabs. Blast Rock Fill may be placed and compacted above the suitable foundation bearing stratum up to 5 ft below footing or slab bearing level. 2. Blast Rock Fill Below Site Areas. a. Blast Rock Fill used in general site areas (outside building areas) may be placed up to within 36 inches of finish grade in paved areas, to within two feet of finish grade in lawn areas, and to within 18 inches of inverts of utility lines. First lift over the top of Rock Fill shall be a choke stone layer 18 inches thick. Compaction shall be by minimum of four coverages of a self- propelled vibratory drum roller in each direction (i.e., north-south and east- west). The minimum weight of the drum shall be 10,000 lbs. b. Blast Rock Fill shall not be placed within a 5-foot horizontal distance on either side of any proposed utility line. The intent is to leave a zone of granular fill that can later be excavated for installation of utilities. Also, large rock fragments should be kept away from utility pipes. K. Processed Rock Fill: unlikely to be used on this project; data offered for completeness 1. Use Processed Rock Fill directly over blast rock fill up to footing or slab bearing level. L. Choke Stone: Use in general site areas directly over Blast Rock Fill (See Blast Rock Fill in Site Area above) and in other areas as shown on the Drawings. M. Filter Fabric/Geotextiles: Use Filter Fabrics around foundation perimeter drains, underslab drains, and other drains where required to prevent siltation of coarser-grained materials. Use Stabilization fabric to stabilize subgrades where directed by the Geotechnical Engineer. N. Riprap: Use riprap for slope stabilization and for erosion control in channel bottoms and at pipe outlets where shown on the Drawings. O. Gravel Filter Layer: Use Gravel Filter Layer material for pipe ends/energy dissipaters, and as shown on the Drawings. P. Dense Graded Crushed Stone - Use for base course material in pavement sections requiring heavy-duty flexible pavement and in other areas shown on the Drawings. Q. Impervious Soil Borrow shall be used to line detention basins as shown on the Drawings. 31 2200 - Earthwork Page 14 of 24 PART 3 - EXECUTION 3.01 STRIPPING, HANDLING, SEGREGATION AND STOCKPILING OF MATERIALS A. During the course of the Work, various quantities of materials will be accumulated and stockpiled for future re-use on-site or for off-site disposition. The Contractor shall handle, segregate to prevent intermixing, protect, stockpile, and dispose of the excavated soils as required, in accordance with these Specifications. B. Materials shall not be stockpiled within the limits of any 100 ft. Wetlands Buffer Zones shown on the Drawings. C. Strip any and all topsoil to its full depth within the Contract limits. Topsoil shall be processed to remove all roots, stones larger than 2 inches in diameter and other deleterious materials and stockpiled as approved by the Geotechnical Engineer. Protect topsoil from contamination from other materials. 3.02 EXCAVATION A. General Requirements 1. Excavation shall include the removal of all materials encountered including fill, native soil, bedrock, boulders, blast rock, pavement, existing debris, trash, utilities and incidental structures. 2. The required excavations may encounter groundwater. Groundwater was encountered within 5 feet of existing site grade (see geotechnical report pages 17-18 and page 23). Surface water flooding on-site from perimeter ditching associated with tidal fluctuation coupled with storm events has occurred here. 3. The Contractor shall control the grading so that ground is pitched to prevent water from running to excavated areas, damaging other structures, or adjacent properties. 4. Surface water and groundwater control by the Contractor is part of this contract. Remove by pumping or other means water accumulated in excavations until earthwork operations are complete. All dewatering shall be performed at the Contractor's cost. 5. Where soil has been softened or eroded by flooding or placement during unfavorable weather, it shall be removed and replaced with suitable material at no cost to the Owner. 6. Exercise care to preserve the material below and beyond the lines of excavation. Where excavation is carried out, through error, below indicated grade or beyond the lines of excavation, backfill to the indicated grade and compact with approved fill at no additional cost to the Owner, and at the direction of the Architect. 7. The Contractor shall provide sheathing, shoring and bracing to complete and protect all excavated areas, as required for safety or compliance with OSHA, at no additional cost to the Owner. The Contractor shall be solely responsible for maintaining site safety, in accordance with OSHA, the Contractor’s Health and Safety Plan and other applicable regulations. 8. Excavated materials unsuitable for reuse and surplus excavated soil not used to fulfill requirements of the Contract shall become the property of the Contractor 31 2200 - Earthwork Page 15 of 24 and shall be removed from the site in accordance with the regulations and requirements of all municipalities or agencies having jurisdiction over the disposal sites and the route between the project and the disposal sites. 9. All excavation and backfilling shall be performed in-the-dry. 10. Where excavations are made to remove unsuitable fill and any organic soils beneath the planned building foundations, slabs, or other structural elements, excavations shall be completed to the top of naturally-deposited, undisturbed inorganic soil (clean glacial fluvial sand). The horizontal limits of excavation shall be sufficient to place Compacted Structural Fill to a horizontal limit equal to the height of the required fill plus 1 foot beyond the edge of the proposed structural element down to the suitable natural inorganic bearing soil (Zone of Influence). 11. Dewater and maintain drainage control in accordance with this Section. 3.03 EXCAVATION CLASSIFICATIONS A. Unclassified Excavation 1. Excavation shall be unclassified and no consideration will be given to the nature of the materials. Unclassified excavation shall comprise and include the satisfactory removal and disposal of all materials encountered regardless of the nature of the materials and shall be understood to include but not be limited to fill, native soils, pavements, curbs, piping, trash, debris, concrete, drainage structures and utility structures abandoned and not removed. B. Trench Excavation 1. Trench excavation shall include the removal and satisfactory disposal of all materials encountered in the construction of drainage, water, sewer, electric, telephone, gas, and other necessary utilities. 2. Excavate all fill and native soil to at least 6 inches below utility lines. Backfill with compacted bedding material as specified. 3. Excavations for manholes, catch basins and miscellaneous site structures shall provide 12-inch minimum clearance on all sides. 4. Trench excavation shall be of sufficient width and depth at all points to allow pipes to be laid, and appurtenant work to be built in a workman-like manner and, when needed, to allow for sheeting and shoring, pumping and draining, and/or for removing and replacing any materials unsuitable for support. 5. Trenches shall be excavated to the minimum limits shown on the Drawings. 6. The Contractor shall furnish, place, remove or leave in place (as directed) all sheeting and bracing required to support the sides of all trenches of other excavations in accordance with OSHA. 7. Where organic deposits or soft or unstable materials (in the opinion of the Geotechnical Engineer or Testing Agency) are encountered at excavation subgrade, the unstable soils shall be over-excavated at least 1 foot below required excavation subgrade or deeper as necessary to form a firm and stable subgrade. Place sub-bedding material consisting of compacted gravel borrow or ¾-inch crushed stone wrapped in non-woven filter fabric (Mirafi 140N or 31 2200 - Earthwork Page 16 of 24 equivalent) up to the bottom of the required pipe bedding material. In all cases, the Contractor shall provide a firm, stable subgrade to place the bedding and construct the utility. The additional excavation and backfilling work shall be performed at no additional cost to the Owner. 3.04 SUBGRADE PREPARATION AND PROTECTION A. General Requirements 1. Remove vegetation, debris, unsatisfactory soil materials, obstructions, and deleterious materials from ground surface prior to placement of fills. Plow, strip, or break up sloped surfaces steeper than one vertical to four horizontal so that fill material will bond with existing surface. Subgrades that become soft or unstable due to inadequate dewatering, caving of the excavation, prolonged exposure, improper methods or other causes shall be re-excavated and re-prepared, at no additional cost to the Owner. 2. All subgrade areas shall be made ready for fill by removal of all organic material, unsuitable soils and deleterious materials as directed by the Architect. 3. Care shall be taken to avoid disturbance to native inorganic soil (clean glacial fluvial sand) or previously-placed fill subgrades in areas to receive fill or support future structures. 4. Upon completion of the required excavation and observation of the subgrade by the Geotechnical Engineer, the subgrade shall be re-compacted as required above to provide a firm, stable subgrade without excessive weaving and instability. 5. In areas of weaving or soft or unstable soils, the soft materials shall be excavated and replaced with Compacted Structural Fill, compacted crushed stone or other acceptable materials to the limits as recommended by the Geotechnical Engineer, at no additional cost to the Owner. B. Proof Rolling Subgrades (Outside Building Area) 1. Prior to placement of fill, proof roll natural ground by making a minimum of two passes with approved compaction equipment. 3.05 PLACEMENT AND COMPACTION OF MATERIALS A. General Requirements 1. Place and compact fill to the limits, of the types and in the manner as specified herein. Unless otherwise specified or directed, material used for filling and backfilling shall meet the requirements specified under Part 2, Products. If material removed from the excavations does not meet the requirements, new material from an approved off-site source which does meet the criteria shall be used for backfilling. 2. Placement of fill shall not begin prior to observation and approval of subgrade conditions by the Geotechnical Engineer or Testing Agency. The Contractor shall not place any fill material in the absence of the Geotechnical Engineer or Testing Agency. 31 2200 - Earthwork Page 17 of 24 3. Dewater subgrade areas prior to filling. 4. Compaction by puddling or jetting is prohibited. 5. Control groundwater and surface runoff to minimize disturbance of material being placed. 6. Do not place fill on frozen ground. 7. Do not place frozen fill. 8. Place fill in uniform horizontal layers and compact immediately after placement. 9. Slope fill surfaces at the end of each day to provide for free surface drainage. 10. Protect structures and pipes from damage during backfilling operations. 11. Placement of fill shall not begin prior to inspection and approval of subgrade conditions by the Geotechnical Engineer or Testing Agency. 12. Protect foundations, footings, and any waterproofing during backfilling. Repair damage at no cost to Owner. 13. If excessive weaving or instability is observed during compaction, as judged by the Geotechnical Engineer or Testing Agency, compaction efforts shall be discontinued until the Contractor stabilizes the subgrade. If required, the Contractor shall excavate and replace the unstable material with acceptable compacted material, at no additional cost to the Owner. 14. Prior to backfilling between foundation wall and any sheeting, remove unsuitable material, including rubbish, organic materials or other debris. Do not commence filling operations until conditions have been observed by the Geotechnical Engineer or Testing Agency and/or Architect. 15. Backfill shall not be placed against walls until they are braced or have cured sufficiently to develop strength necessary to withstand, without damage, pressure from backfilling and compacting operations. 16. Place Compacted Structural Fill within an envelope defined by 1 foot horizontally from the bottom the structural element (including all building concrete aprons and building sidewalks) at the bearing elevation, and down on 1H:1V slope to suitable natural inorganic bearing soil. 17. Provide suitable transition layers or non-woven filter fabric, as required to prevent the migration of fine material into void spaces of coarser material. Transition layers may consist of limited thickness of ¾-inch Crushed Stone (less than 6 inches thick), lean concrete or other methods approved by the Geotechnical Engineer. 18. The on-site fill soils may contain various types and quantities of miscellaneous debris including, but not limited to, boulders, wood, brush, organics, concrete, and other miscellaneous debris that has not be segregated. Prior to or during reuse as Common Fill, the Contractor shall remove all organic material and non- soil materials, except brick and non-reinforced concrete (1.5-in. maximum size), so that the material can be placed and compacted to form a firm, stable subgrade and fill (in the judgment of the Geotechnical Engineer or Testing Agency), and 31 2200 - Earthwork Page 18 of 24 meet the required compaction. Additional measures that the Contractor could use may include, but are not limited to, screening the material or placing the material in thinner lifts than typically required so the debris can be removed (culled out). B. Equipment 1. Compaction equipment used to compact soil in open areas, where space permits, shall consist of vibratory rollers weighing at least 15,000 pounds applying a dynamic centrifugal force of at least 22,000 pounds, fully-loaded ten- wheel dump trucks, pneumatic compactors or other similar approved equipment sufficient to provide a firm, stable subgrade and achieve the required compaction. Compaction equipment used to compact crushed concrete in open areas, where space permits, shall consist of vibratory rollers applying a dynamic centrifugal force of at least 30,000 pounds. 2. Compaction equipment used to compact soil fill materials in tight access areas shall consist of a walk-behind vibratory drum roller or other equivalent equipment having at least 10,000 pounds centrifugal force with at least four passes and sufficient to provide a firm, stable subgrade and achieve the required compaction. Hand-guided equipment shall not be used to compact crushed concrete. 3. Compaction equipment used to compact soil fill materials adjacent to below- grade walls shall consist of small, walk-behind vibratory drum rollers or large vibratory plate compactors with at least four passes and sufficient to provide a firm, stable subgrade and achieve the required compaction. The above equipment shall be used to compact all fills from the face of the wall a distance equal to the height of the fill lift above the bottom of the wall. 4. The Contractor shall use compaction equipment appropriate to obtain the specified compaction at all times. In some cases, additional passes or heavier equipment may be required. The gradation of some materials on-site (particularly high gravel content mixes) are such that field unit weight testing methods (sand cone and nuclear density equipment) may not provide representative compaction results. In these cases, the Geotechnical Engineer or Testing Agency will use judgment in evaluating if the Contractor achieved the intent of the specifications. 3.06 TRENCH BACKFILL A. Trenches shall be backfilled as soon as practicable with suitable approved material. All trench backfilling shall be done with special care, in the following manner and as the Geotechnical Engineer or Testing Agency may direct from time to time. B. Utility bedding material for pipe bedding shall be deposited in the trench, uniformly on both sides of the pipe, for the entire width of the trench to the springline of the pipe. The backfill material shall be placed by hand shovels, in layers not more than 4 inches thick in loose depth, and each layer shall be thoroughly and evenly compacted by tamping on each side of the pipe to provide uniform support around the pipe, free from voids. C. The balance of backfill shall be spread in layers not exceeding 6 inches in loose depth. Each layer shall be dampened, thoroughly compacted by tamping or other approved method and shall meet the density requirements specified herein. 31 2200 - Earthwork Page 19 of 24 D. All trench backfilling shall be done with special care and must be carefully placed so as not to disturb the work at any time. The moisture content of the backfill material shall be such that proper compaction will be obtained. Puddling of backfill with water will generally not be permitted except as specified below. Backfill within areas of pavement construction shall be made to grades required to establish the proper pavement base courses. E. In backfilling trenches, each layer of backfill material shall be moistened and compacted to a density at least equal to that of the surrounding undisturbed soil, and in such a manner as to permit the rolling and compaction of the filled trench or excavation with the adjoining earth to provide the required bearing value, so that paving of the excavated and disturbed areas, where required, can proceed immediately after backfilling is completed. F. Any trenches or excavations improperly backfilled or where settlement occurs shall be reopened, to the depth required for proper compaction, then refilled and compacted with the surface restored to the required grade and condition, at no additional expense to the Owner. G. During filling and backfilling operations, pipelines will be checked by the Architect to determine whether any displacement of the pipe has occurred. If the inspection of the pipelines shows poor alignment, displaced pipe or any other defects shall be remedied in a manner satisfactory to the Engineer at no additional cost to the Owner. H. Trench backfill material above the utility bedding material, for utilities located outside the building limits, may consist of the excavated soils, provided the excavated soils meet the requirements of Common Fill, and can be readily spread and compacted. Peat, organic silt, loam and other organic soils shall not be used as trench backfill. 3.07 BACKFILL AND FILL A. Ground Surface Preparation: Remove vegetation, debris, unsatisfactory soil materials, obstructions, and deleterious materials from ground surface prior to placement of fills. Plow, strip, or break up sloped surfaces steeper than one vertical to four horizontal so that fill material will bond with existing surface. B. Subgrade Preparation: After the subgrade has been shaped to line, grade, and cross section, it shall be thoroughly compacted. This operation shall include any required reshaping and wetting to obtain proper compaction. All soft or otherwise unsuitable material shall be removed and replaced with suitable material from excavation or borrow. The resulting area, and all other low sections, holes, or depressions shall be brought to the required grade with approved material and the entire subgrade shaped to line, grade and cross section and thoroughly compacted. C. Frost Protection: Frozen material shall not be placed as fill or backfill. No fill shall be placed over frozen ground. D. Backfill Material Selection: Unless otherwise specified or directed, material used for filling and backfilling shall meet the requirements specified under Part 2—Products. If material removed from the excavations does not meet the requirements specified for common fill, new material which does meet this criteria shall be used for backfilling utility trenches. All backfill placed within the building limits shall be sand and gravel fill unless otherwise specified. 31 2200 - Earthwork Page 20 of 24 3.08 BACKFILLING AGAINST STRUCTURES A. Backfilling against masonry or concrete shall only be done when approved. The Contractor shall not place backfill against or on structures until they have attained sufficient strength to support the loads (including construction loads) to which they will be subjected, without distortion, cracking or other damage. As soon as practicable after the structures are structurally adequate and other necessary work has been satisfactorily completed, special leakage tests of the structures shall be made by the Contractor, as required by the Architect, at the Contractor's expense. After the satisfactory completion of leakage tests and the satisfactory completion of any other required work in connection with the structures, the backfilling around the structures shall proceed using suitable and approved material. Just prior to placing backfill, the areas shall be cleaned of all excess construction material and debris and the bottom of excavations shall be in a thoroughly compacted condition. B. Symmetrical backfill loading shall be maintained. Special care shall be taken to prevent any wedging action or eccentric loading upon or against the structures. During backfilling operations, care shall be exercised that the equipment used will not overload the structures in passing over and compacting these fills. Except as otherwise specified or directed, backfill shall be placed in layers not more than 12 inches in loose depth and each layer of backfill shall be compacted thoroughly and evenly using approved types of mechanical equipment. Each pass of the equipment shall cover the entire area of each layer of backfill. C. In compacting and other operations, the Contractor shall conduct his operations in a manner to prevent damage to structures due to passage of heavy equipment over, or adjacent to, structures, and any damage thereto shall be made good by the Contractor at no additional expense to the Owner. D. After backfilling trenches and excavations, the Contractor shall maintain the surfaces of backfill areas in good condition so as to present a smooth surface at all times level with adjacent surfaces. Any subsequent settling over backfilled areas shall be repaired by the Contractor immediately, in a manner satisfactory to the Architect, and such maintenance shall be provided by the Contractor for the life of this Contract, at no additional expense to the Owner. E. The finished subgrade of the filled excavations upon which pavements are to be constructed shall not be disturbed by traffic of other operations and shall be maintained in a satisfactory condition until the finished courses are placed. The storage or stockpiling of materials on finished subgrade will not be permitted. F. Uniformly smooth grading of all areas to be graded, as indicated and as directed, including excavated sections and all areas disturbed as a result of the Contractor's operations, shall be accomplished. The finished surfaces shall be reasonably smooth, compacted and free from surface irregularities. 3.09 COMPACTION A. Compaction Requirements 1. The degree of compaction is expressed as a percentage of the maximum dry density at optimum moisture content as determined by ASTM Test D1557, Method C. The minimum compaction requirements are as follows: 31 2200 - Earthwork Page 21 of 24 ASTM Density Degree of Compaction Area D1557 Below footings 95% Below slabs 95% Pavement base course 95% Pavement subbase 95% General fill below pavement subbase 93% Trench backfill 93% Lawn areas 90% B. Moisture Control 1. Fill that is too wet for proper compaction shall be harrowed, or otherwise dried to a proper moisture content to allow compaction to the required density. If fill cannot be dried within 24 hours of placement, it shall be removed and replaced with drier fill. 2. Fill that is too dry for proper compaction shall receive water uniformly applied over the surface of the loose layer. Sufficient water shall be added to allow compaction to the required density. 3. In no case shall fill be placed over material that is frozen. No fill material shall be placed, spread or rolled during unfavorable weather conditions. When work is interrupted by heavy rains, fill operations shall not be resumed until the moisture content and the density of the previously placed fill are as specified. 4. The existing fills and native soils excavated from on-site excavations may be too wet and may require moisture conditioning prior to reuse on-site or other measures as required in order to provide a firm, stable subgrade and achieve the compaction requirements herein. Additional measures such as spreading the material and harrowing the material out to facilitate drying, adding stabilizing agents such as lime to hydrate excess moisture in the material, or other methods, will likely be required in order the place the soils and as a firm, stable compacted fill. C. Lift Thickness of Material 1. Place fill in uniform horizontal layers. 2. Gravel Borrow, Compacted Structural Fill, Sand Borrow and Other Engineered Fill: Place in layers not to exceed 12 inches in loose lift thickness prior to compaction when utilizing heavy self-propelled vibratory compaction equipment, and 8 inches when utilizing hand- operated compaction equipment. Compact material with a minimum of 4 complete coverages per lift. 3. Common Fill. Place in layers not to exceed 12 inches in loose lift thickness prior to compaction when utilizing heavy self-propelled compaction equipment, and 8 inches loose-lift thickness when utilizing light hand-operated compaction equipment. Compact with a minimum of 4 complete coverages per lift with acceptable compaction equipment. 31 2200 - Earthwork Page 22 of 24 4. Crushed Stone, Gravel, Dense Graded Crushed Stone. Place in layers not to exceed 12 inches in loose lift thickness prior to compaction when utilizing heavy self-propelled compaction equipment, and 8 inches loose lift thickness when utilizing light hand- operated compacted equipment. Compact with a minimum of 4 complete coverages per lift of acceptable compaction equipment. 5. Crushed Concrete: Place in layers not exceeding 8 in. in depth measured prior to compaction in open areas, and 6 in. in depth in confined areas. Compact each layer with a minimum of four coverages of the approved equipment. 3.10 SITE SUBGRADE PREPARATION AND FILLING (OUTSIDE BUILDING AREA) A. General Requirements 1. All suitable material removed from the excavations, as determined by the Architect or Site Civil Engineer, shall be used as directed in the formation of fill sections, embankments, subgrade, etc. 2. The Architect or Site Civil Engineer may determine that excavated material from certain strata is unsuitable for use under paved areas, but that such material may be deposited in berms or embankment areas outside the paved. B. Borrow Material: Should there be a deficiency of proper fill material from within the graded area on the site, the Contractor shall supply all such borrow material from other areas approved in writing by the Architect and/or Site Civil Engineer. C. Proofrolling: Prior to placing compacted fills, the Contractor shall proof roll the subgrade. Where materials of low density are indicated by rutting or weaving under the compactor, the Contractor may be required to make up to three (3) additional complete coverages of the area with the compactor as determined by the Architect. The cost of all proof rolling shall be included in the Contract Sum. If materials of low density are encountered that cannot be compacted to the extent necessary to support the proposed embankment fills as determined by the Site Civil Engineer, the Contractor shall remove those materials and replace them with compacted fill. Alternately, an initial layer of fill may be allowed to form a working platform. The need, manner of construction, and thickness of such a layer shall be subject to approval of the Architect and the layer will be permitted only where the lack of support is, as determined by the Architect, not due to deficient ditching, grading or drainage practices, or where the embankment could be constructed in the approved manner by the use of different equipment or procedures. Thicknesses of up to three (3) feet may be permitted for such a layer. D. Placing Fill 1. Fill sections and embankments shall be constructed of earth, rock, or a mixture of earth and rock deposited in successive lifts. Except as hereinafter permitted, the loose thickness of each lift shall not be more than twelve (12) inches before compaction. 2. Rock fill may be used in deep fill areas. 3. No rock in excess of six (6) inches in its largest dimension shall be incorporated in the top two (2) foot layer of embankment immediately below the subgrade. 31 2200 - Earthwork Page 23 of 24 4. During fill and embankment construction operations, earth moving equipment shall be routed as evenly as possible over the entire width of the work. 4. At the close of each day's work the working surface shall be crowned, shaped, and rolled with smooth steel or pneumatic tired rollers to ensure proper drainage. E. Moisture 1. If, in the opinion of the Site Civil Engineer or Testing Agency, the fill material becomes too wet for the required compaction, prior to commencing or continuing compaction operations the fill shall be dried by a method approved by the Site Civil Engineer or Testing Agency (e.g. harrowing). 2. If, in the opinion of the Site Civil Engineer or Testing Agency, the fill material becomes too dry for the required compaction, the fill shall be moistened prior to commencing or continuing compaction operations. F. Protection of Fill 1. Protection of all compacted fill shall be the responsibility of the Contractor. Newly graded areas shall be protected from the actions of the elements and traffic. Any settlement or surface washing that occurs prior to acceptance of the work shall be repaired and grades shall be re-established to the required elevations and slopes. Damage to any compacted lift (including those lifts previously tested and approved by the Site Civil Engineer or Testing Agency) occurring at any time during the course of construction which is caused by equipment, moisture entering the embankment, or from any other cause whatsoever shall be fully repaired by the Contractor prior to placement of any overlying materials at his own expense, to the complete satisfaction of the Site Civil Engineer or Testing Agency. 2. In the event of and prior to the commencement of heavy rains, the Contractor shall suspend fill operations immediately and shall take all necessary steps to keep the site as well drained as possible. Fill operations shall not be resumed until the moisture content of the fill is such as to permit compliance with the Specifications. 3. All corrective work or operations necessary to maintain proper moisture control of the fill material shall be at the expense of the Contractor. 4. The Contractor shall take the necessary steps to avoid disturbance of subgrade and underlying native soils/compacted fill during excavation and filling operations. Methods of excavation and filling operations shall be revised as necessary to avoid disturbance of subgrade and underlying soils/fill, including restricting the use of certain types of construction equipment and their movement over sensitive (such as hard silty clay) or unstable materials, dewatering, and other acceptable control measures. Disturbance shall be construed to include deterioration of fill (after placement and satisfactory compaction) due to the Contractor's operations, such as moving equipment, hauling trucks, etc. The Contractor shall cooperate with the Site Civil Engineer or Testing Agency to modify his operations as necessary to minimize disturbance and protect bearing soils. 5. All excavated or filled areas disturbed during construction, all loose or saturated soil, and other areas that do not meet compaction requirements as specified herein shall be removed and replaced with suitable materials. Fill that cannot be 31 2200 - Earthwork Page 24 of 24 compacted within 24 hours because of its moisture condition shall be removed and replaced with Compacted Structural Fill, compacted crushed stone or other material approved by the Site Civil Engineer. Costs of removal of disturbed material and replacement shall be borne by the Contractor. G. Final Surface 1. Upon completion of the work, ground surface shall be left in a firm, stable, unyielding, uniform condition, free of ruts and surface irregularities, in accordance with the grading requirements shown on the Drawings. 2. Uniformly smooth-grade all areas to be graded, as indicated and as directed, including excavated sections and all areas disturbed as a result of the Contractor's operations. 3.09 IMPORTING AND EXPORTING MATERIAL AND MATERIAL DISPOSAL A. In order to accomplish the required construction, various materials will be required to be imported to the site, such as Gravel Borrow, Compacted Structural Fill, ¾-inch Crushed Stone, Common Fill, Dense Graded Crushed Stone and other materials. The cost of providing all of these required materials shall be included in the base bid for the Work. B. A basic requirement of the Work is to re-use the available on-site materials, as much as possible, except as noted herein. Materials shall not be removed from the site without authorization by the Geotechnical Engineer or Site Civil Engineer. END OF SECTION 312200