SECTION EARTHWORK PART 1 - GENERAL 1.1 RELATED DOCUMENTS

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1 SECTION EARTHWORK PART 1 - GENERAL 1.1 RELATED DOCUMENTS A. Drawings and general provisions of the Contract, including General and Modification to General Conditions and Division 01 Specification Sections, apply to this Section. 1.2 SUMMARY A. The work described in this section includes cutting, grading, filling, and rough contouring the site for structures, buildings, pavement and landscape areas. Exporting surplus materials or importingneeded materials are the responsibility of the contractor. Earthwork operations shall be in accordance with the project geotechnical report. B. Related Sections include: 1. Section Excavation Support and Protection 2. Section Subdrainage 3. Section Sanitary Sewerage Utilities 4. Section Storm Drainage Utilities C. Work Included: 1. Soil materials: a. Subsoil and topsoil materials. 2. Aggregate materials. 3. Rough grading: a. Removal of top soil and sub soil. b. Cutting, grading, filling, and rough contouring the site for structures, buildings, pavement. 4. Excavating: a. Excavating for building foundations. b. Excavating for slabs on grade, paving, landscaping. c. Excavating for utilities within the building and to 5 feet outside the building. d. Excavating for site utilities. 5. Backfilling: a. Building perimeter and site structures backfilling to subgrade elevations. b. Site filling and backfilling, including landscaped areas. c. Fill under slabs on grade EARTHWORK

2 d. Fill under paving. e. Consolidation and compaction. f. Fill for over-excavation. g. Sheet vapor retardant (vapor barrier) and aggregate ballast (sand cushion). h. Geotextile fabric. i. Backfilling of utilities within the building and to 2 feet outside the building. j. Backfilling for utilities not within pavement areas. 6. Trenching: a. Excavating trenches for utilities from 2 feet outside building to municipal connections. b. Compacted fill from top of utility bedding to subgrade elevations. c. Backfilling and compaction. d. Geotextile fabric. 7. Aggregate Base Course 1.3 DEFINITIONS A. Excavation consists of removal of material encountered to subgrade elevations indicated and subsequent disposal of materials removed. B. Unauthorized excavation consist of removal of materials beyond indicated subgrade elevations or dimensions without specific direction of Engineer. Unauthorized excavation, as well as remedial work directed by Engineer, shall be at Contractor's expense. 1. Under footings, foundation bases, or retaining walls, fill unauthorized excavation by extending indicated bottom elevation of footing or base to excavation bottom, without altering required top elevation. Lean concrete fill (1,000 psi concrete or 1000 PSI K- Krete) may be used to bring elevations to proper position, when acceptable to Engineer. 2. In locations other than those above, backfill and compact unauthorized excavations as specified for authorized excavations of same classification, unless otherwise directed by Engineer. C. Additional Excavation: When excavation has reached required subgrade elevations, notify Soils Engineer, who will make an inspection of conditions. If Soils Engineer determines bearing material at required subgrade elevations are unsuitable, continue excavation until suitable bearing materials are encountered and replace excavated material as directed by Soils Engineer. The Contract Sum may be adjusted by an appropriate Contract Modification. D. Subgrade: Undisturbed earth or compacted soil layer immediately below granular sub-base, drainage fill, or topsoil materials. E. Borrow: Soil material obtained off-site when sufficient approved soil material is not available from excavations. F. Sub-base Course: A preparatory course constructed over an inadequate subgrade and below the base course in a paving system EARTHWORK

3 G. Aggregate Base: Course of washed granular material supporting slab-on-grade placed to cut off upward capillary flow of capillary water. In a paving system, the foundations course of a pavement structure placed upon a prepared subgrade or sub-base. H. Structure: Buildings, footings, foundations, slabs, curbs, or other man-made stationary features occurring above or below ground surface. 1.4 SUBMITTALS A. Material Test Reports: From a qualified testing agency indicating and interpreting test results for compliance of the following with requirements indicated: 1. Classification according to ASTM D 2487 of each borrow soil material proposed for fill and backfill. 2. Laboratory compaction curve according to ASTM D 698 for each on-site or borrow soil material proposed for fill and backfill. 3. Aggregate base. PART 2 - PRODUCTS 2.1 SOIL MATERIALS A. Top Soil: 1. Excavated and reused material, graded, free of roots, rocks larger than 1/2", subsoil, debris, large weeds and foreign matter or imported friable loam; reasonably free of roots, rocks larger than 1/2", subsoil, debris, large weeds, and foreign matter; acidity range (ph) of 5.5 to 7.5; containing a minimum of 3% and a maximum of 20% organic matter; conforming to ODOT CMS Item B. Subsoil Fill Material: 1. Excavated and re-used material, graded, free of lumps larger than 3", rocks larger than 2" or imported material, graded, free of lumps larger than 3", rocks larger than 2", and debris conforming to ASTM D2487 Group Symbol. Material shall be capable of compaction in accordance with requirements of project geotechnical report. C. Backfill: 1. Coarse Aggregate: Size #57 conforming to ODOT CMS Item Fine Aggregate: Sand conforming to ODOT CMS Item , Concrete: Lean concrete conforming to ODOT Item 305 with a compressive strength of 1000 psi. 4. Subsoil: Material type as listed in B Controlled Density Fill (CDF) (Conforming to ODOT Item 613): a. Controlled density fill shall have strength levels between 100 psi and 150 psi. b. Initial trial mixture shall be as follows (cubic yard basis):

4 D. Aggregate Base: 1) Cement 90 lbs. 2) Fly Ash 250 lbs. 3) Water 55 lbs. 4) Fine Aggregate 2850 lbs. c. These quantities of materials are expected to yield approximately one cubic yard of fill of the proper consistency. Adjustments of the proportions may be made providing the total absolute volume of the materials is maintained. d. Mix proportioning shall be adjusted to achieve necessary flowability and strength. The design compressive strength shall be between 100 psi and 150 psi at 28 days. Care shall be exercised in mix proportioning to prevent achieving greater strengths than specified. e. Cement shall conform to ASTM C-150, Type 1. f. Fly ash shall be Class F, ASTM C Material conforming to ODOT CMS Item 304. Aggregate made from recycled concrete is not permitted and shall not be used. E. Sub-base: 1. Material conforming to ODOT CMS Item 304. Aggregate made from recycled concrete is not permitted and shall not be used. F. Engineered Fill: 1. Sub-Soil fill materials as noted in B.1 above, or backfill material as noted in C above, constructed and compacted in accordance with the project geotechnical requirements and the plans. 2.2 GEOTEXTILES A. Subsurface Drainage Geotextile: Nonwoven needle-punched geotextile, manufactured for subsurface drainage applications, made from polyolefins or polyesters; with elongation greater than 50 percent; complying with AASHTO M 288 and the following, measured per test methods referenced: 1. Survivability: Class 2; AASHTO M Grab Tensile Strength: 157 lb; ASTM D Sewn Seam Strength: 142 lb; ASTM D Tear Strength: 56 lb; ASTM D Puncture Strength: 56 lb; ASTM D Apparent Opening Size: No. 60 sieve, maximum; ASTM D Permittivity: 0.01 per second, minimum; ASTM D UV Stability: 50 percent after 500 hours exposure; ASTM D B. Separation Geotextile: Woven geotextile fabric, manufactured for separation applications, made from polyolefins or polyesters; with elongation less than 30 percent; complying with ODOT Type D and the following, measured per test methods referenced:

5 1. Survivability: Class 2; AASHTO M Grab Tensile Strength: 200 lb; ASTM D Sewn Seam Strength: 222 lb; ASTM D Tear Strength: 70 lb; ASTM D Puncture Strength: 95 lb; ASTM D Apparent Opening Size: No. 40 sieve, maximum; ASTM D Permittivity: per second, minimum; ASTM D UV Stability: 50 percent after 500 hours exposure; ASTM D C. Reinforcing Fabric 1. Reinforcing fabric shall be made from woven polypropylene containing heavy monofilament and fibrillated yarns with the minimum physical properties: a. Grab Strength ASTM D lbs b. Mullen Burst ASTM D psi c. Trapezoidal Tear ASTM D psi d. Water Flow Rate ASTM D gpm 2. Typically used as subgrade stabilization D. Reinforcing Geogrid 1. Reinforcing geogrid shall be made from polypropylene with the minimum physical properties: a. True Initial Modulus In Use Type I 17,140 lb/ft b. Flexural Stiffness Type I 250,000 cm c. Aperture Stability Modulus Type I 3.2 deg d. Resistance to Installation Damage Type I 70% GP 2. Typically used as subgrade stabilization E. Manufacturers 1. TenCate Mirafi. 2. SI Geosolutions 3. US Fabrics 4. Geo-Synthetics 5. PS Construction Fabrics PART 3 - EXECUTION 3.1 PREPARATION A. Identify required lines, levels, contours, and datum. B. Locate, identify, and protect utilities that remain, from damage. C. Notify utility companies to remove and/or relocate utilities.

6 D. Protect plant life, trees, lawns, rock outcropping and other features remaining as a portion of final landscaping. E. Protect bench marks, existing structures, fences, sidewalks, paving, and curbs from excavation equipment and vehicular traffic. 3.2 EXCAVATION (GENERAL) A. Underpin adjacent structures which may be damaged by excavation work. B. Excavate topsoil and subsoil required to accommodate building foundations, slabs-ongrade, paving and site structures, construction operations. C. Machine slope banks to angle of repose or less, until shored. D. Do not interfere with 45 bearing splay of foundation. E. Grade top perimeter of excavation to prevent surface water from draining into excavation. F. Remove lumped subsoil, boulders, and rock up to 1 cu. yd. measured by volume from site. G. Notify Engineer of unexpected subsurface conditions and discontinue affected work in areas until notified to resume work. H. Protect excavations by methods required to prevent cave-in or loose soil from falling into excavation. I. Protect bottom of excavations and soil adjacent to and beneath foundation, from freezing. J. Excavate subsoil required for utilities installation. K. Cut utility trenches sufficiently wide to enable installation and allow inspection. L. Barricade open excavations occurring as part of this work and post with warning lights and signs. Provide, erect and maintain temporary fences and guardrails as required. All such measures shall conform to applicable Federal, State and Local laws, rules and regulations. 3.3 SITE FILLING AND BACKFILLING (GENERAL) A. Preparation: 1. The building and pavement subgrades should then be shaped and proof-compacted with sufficient equipment. Areas which fail to stabilize or which become unstable beneath the compaction equipment should be undercut and replaced with structural fill consisting of a combination of #1 and #2 crushed natrual aggregate rolled into the subgrade and choked off with ODOT Item 304 or as approved by the project geotechnical engineer. 2. All excavations at the site should be designed and performed in accordance with the criteria presented in 29 CFR Part 1926 of the Occupational Safety and Health

7 Standards Excavations, Final Rule. Excavations should extend to depths as necessary to establish the plan subgrades or remove unsuitable soils in their entirety. The excavated subgrades should be crowned and sloped to direct any collected precipitation and any groundwaters which enter the excavations to their periphery where swales, sumps and pumps should be located to dewater the excavations. 3. All excavations should be completed so as not to undermine the foundations of the adjacent structures or utilities. In general, excavations at the sites should not encroach within an existing foundation or utilities zone of influence defined by a line extending out and down from the existing foundation, grade beam or utility at an inclination of one (1) vertical on one (1) horizontal. Excavations which encroach within the zone should be sheeted, shored and/or braced to support the soil adjacent structure loads; or, the foundation or utility should be underpinned to establish it s bearing at a deeper level. 4. All excavation subgrades and structural fill surfaces should be crowned or sloped to direct precipitation, runoff or groundwater which enters the excavations to their periphery. Sumps and pumps should be used as required to depress and remove water and to maintain the excavations in the dry. 5. Stabilization of isolated subsurface materials may be possible by using crushed stone to bridge or choke into the yielding materials, as approved by the project geotechnical engineer. B. Site Filling: 1. Fill areas to contours and elevations with unfrozen materials. 2. On-site soil (excluding topsoil or any unsuitable material as determined by a soil engineer), as encountered in the borings, is considered suitable for use as fill when compacted at the proper moisture content. a. Fill soil placed for foundation and pavement support should be placed in loose lifts. The first lift of material should be only approximately four (4) inches thick in the loose state. Each lift of soil thereafter should be placed in maximum eight (8) inches loose thickness, within plus or minus two (2) percent of the optimum moisture content, as determined by the Standard Proctor test (ASTM D-698). Fill soil placed under pavement or structures shall be compacted in accordance with the subsurface soil investigation report prepared by the project geotechnical engineer. Fill soil with a maximum dry unit weight of between 90 and 105 pounds per cubic foot (pcf) shall be compacted to not less than 98% of its maximum dry density 1.5%. Soil with a maximum dry density of less than 90- pcf should not be employed as fill material. Fill soil containing excess moisture shall be required to dry prior to or during compaction to a moisture content not greater than 2% above or below optimum. Drying of wet soil shall be expedited by the use of plows, discs, or by other approved methods when so ordered by the site soil engineer. 3. Maintain optimum moisture content of fill materials to attain required compaction density. 4. Make grade changes gradual. Blend slope into level areas. 5. Remove surplus fill materials from site. 6. Grade top surface of subgrade to ± 1/2 of plan elevations, grade the detention basin to ±1/2 of plan elevations. 7. Building pads shall be graded to 8 below finish floor elevation. Center of the pad

8 shall be installed with a very slight crown to drain without trapping or ponding water. 8. The contractor shall provide temporary swales to drain the building pad and pavement areas. 9. The contractor shall smooth roll all disturbed areas within the building pad and pavement areas prior to expected rainfall events. No ponding of water is permitted to occur on the building pad or pavement areas. C. Subgrade Inspection: 1. Notify Architect when excavations have reached required subgrade. 2. If Architect determines that unsatisfactory soil is present, continue excavation and replace with compacted backfill or fill material as directed. 3. Proof-roll subgrade below the building slabs and pavements with heavy pneumatictired equipment to identify soft pockets and areas of excess yielding. Do not proof-roll wet or saturated subgrades. a. Completely proof-roll subgrade in one direction, repeating proof-rolling in direction perpendicular to first direction. Limit vehicle speed to 3 mph (5 km/h). b. Proof-roll with a loaded 10-wheel, tandem-axle dump truck weighing not less than 15 tons (13.6 tonnes). c. Excavate soft spots, unsatisfactory soils, and areas of excessive pumping or rutting, as determined by Architect, and replace with compacted backfill or fill as directed. 4. Authorized additional excavation and replacement material will be paid for according tocontract provisions for changes in the Work. 5. Reconstruct subgrades damaged by freezing temperatures, frost, rain, accumulated water, or construction activities, as directed by Architect, without additional compensation. D. Backfilling: 1. Backfill areas to contours and elevations with unfrozen materials. 2. Systematically backfill and provide proper compaction. Do not backfill over porous, wet, frozen or spongy subgrade surfaces. 3. Coarse aggregate or fine aggregate: Place and compact materials in continuous layers not exceeding 6" compacted depth. 4. Aggregate base and sub-base: Place and compact materials in continuous layers not exceeding 6" compacted depth. 5. Subsoil: Place and compact material in continuous layers not exceeding 8" loose depth. 6. Employ a placement method that does not disturb or damage other work. 7. Maintain optimum moisture content of backfill materials to attain required compaction density. Backfill against supported foundation walls. Do not backfill against unsupported foundation walls. 8. Backfill simultaneously on each side of unsupported foundation walls until supports are in place. 9. Make gradual grade changes. Blend slope into level areas. 10. Remove surplus backfill materials from site. 11. Leave fill material stockpile areas free of excess fill materials. 12. Grade top surface of backfilling under paved areas and structures, ±¼ from required elevations.

9 13. Grade top surface of general backfilling: ±½ from required elevations. E. Aggregate Placement (General): 1. Place aggregate in maximum 6" layers and compact. 2. Level and contour surfaces to elevations and gradients indicated. 3. Add water to assist compaction. If excess water is apparent, remove aggregate and aerate to reduce moisture content. 4. Use mechanical tamping equipment in areas in accessible to compaction equipment. 5. Tolerances: a. Flatness: Maximum variation of 1/4" measured with 10 foot straight edge. b. Scheduled Compacted Thickness: Within 1/4". c. Variation from True Elevation: Within 1/4". 3.4 FIELD QUALITY CONTROL A. Field inspection and testing will be performed under provisions of Division 1. B. Compaction testing will be performed in accordance with ANSI/ASTM D698. C. If tests indicate work does not meet specified requirements, remove work, replace and retest. D. Frequency of Tests: Perform one fill density test for every 1,000 SF of each lift placed. 3.5 EROSION CONTROL A. Provide erosion control methods in accordance with project plans and authorities having juris- diction. B. Smooth roll disturbed earth area to seal surface prior to rainfall events to reduce erosion. C. Install rock or stone check dams and diversion berms such that runoff is directed into sediment control traps or basins. 3.6 MAINTENANCE (GENERAL) A. Stockpiling: 1. Stockpile materials on site at locations indicated or approved by Engineer. 2. Stockpile in sufficient quantities to meet project schedule and requirements. 3. Separate differing materials with dividers or stockpile apart to prevent mixing. 4. Direct surface water away from stockpile site so as to prevent erosion or deterioration of materials. 5. Install and maintain silt fence around stockpile. Provide seeding and establish temporary vegetation cover.

10 B. Stockpile Cleanup: 1. Remove stockpile, leave area in a clean and neat condition. Grade site surface to prevent freestanding surface water. Provide seeding and establish permanent vegetation cover. C. Dewatering: 1. Prevent surface water and subsurface or ground water from flowing into excavations and from flooding project site and surrounding area. a. Do not allow water to accumulate in excavations. Remove water to prevent soften- ing of foundation bottoms, undercutting footings, and soil changes detrimental to stability of subgrades and foundations. Provide and maintain pumps, well points, sumps, suction, and discharge lines, and other dewatering system components necessary to convey water away from excavations. b. Establish and maintain temporary drainage ditches and other diversions outside excavation limits to convey rain water and water removed from excavations to collecting or runoff areas. Do not use trench excavations as temporary drainage ditches. c. Provide temporary drainage structures as detailed on plans as "manhole/catch basin/inlet ~ abandonment and temporary usage." Number of such structures to be determined at Contractor's option. d. Protection of Finished Work: 1) Protect finished work under provisions of Division 1. 2) Reshape and re-compact fills subjected to vehicular traffic during construction. 3.7 SCHEDULE OF EMBANKMENT SOIL COMPACTION Compaction and moisture content of suitable soil material shall be in accordance with the project subsurface soil investigation report, prepared by the project geotechnical engineer. A. Exterior Slab-On-Grade Areas: 1. Engineered Fill (2.1.F.1), (Depth Varies); Compacted to 96% (min.) of maximum dry density per ASTM-D Fine aggregate backfill (2.1.C.2), 4 inches thick, compacted to 96% (min.) of maximum density per ASTM-D-4253 and D Pipe trenches within the building areas shall be backfilled with suitable inert, granular material and properly compacted in 6" lifts to 96% of the maximum density per ASTM- D-4253 and D B. Fill Under Grass Areas and Athletic Play Fields: 1. Subsoil fill material (2.1.B.1), 6 inches below finish grade, compacted to 94% (min.) of maximum dry density per ASTM-698.

11 C. Fill Under Landscape Areas: 1. Subsoil Fill Material (2.1.B.1), 12 inches below finish grade, compacted to 96% (min.) of maximum dry density per ASTM-698. D. Fill Under Paving and Trench Backfill within 5 feet of Pavement: 1. Compact subsoil to 96% of its maximum dry density per ASTM D Engineered fill (depth varies), compacted to 96% of its maximum dry density per ASTM D-698. E. Fill Under Building, Building Foundation, and Within 10 of Building: 1. Compact subsoil to 98% of its maximum dry density per ASTM D Engineered fill (depth varies), compacted to 98% of its maximum dry density per ASTM D-698. END OF SECTION