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SECTION 312000 – SITE PREPARATION AND EARTHWORK

PART 1 - GENERAL

1.01 RELATED DOCUMENTS: A. Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 01 Specification Sections, apply to this Section.

1.02 SUMMARY: A. This Section includes Site preparation activities and certain items of earthwork common to other related work. B. Related Work Specified Elsewhere: 1. Section 312020 - Excavation and Backfill.

1.03 REFERENCES: A. Applicable Standards: 1. American Association of State and Transportation Officials (AASHTO): a. M80 - Coarse Aggregate for Portland Cement . b. T99 - The Moisture-Density Relations of Using a 5.5-lb. Rammer and a 12-inch Drop. c. T104 - Soundness of Aggregate by Use of Sodium Sulfate or Magnesium Sulfate. d. T180 - The Moisture-Density Relations of Soils Using a 10-lb. Rammer and an 18-inch Drop. 2. American Society for Testing and Materials (ASTM): a. D2167 - Test Method for Density and Unit Weight of in Place by Rubber Balloon Method. b. D4253 - Test Method for Maximum Index Density and Unit Weight of Soils Using a Vibratory Table. c. D4254 - Test Method for Minimum Index Density and Unit Weight of Soils and Calculation of Relative Density. d. D4318 - Test Method for Liquid Limit, Plastic Limit, and Plasticity Index of Soils. e. D4546 - Test Methods for One-Dimensional Swell/Settlement Potential of Cohesive Soils. f. D6938 - Standard Test Methods for In-Place Density and Content of Soil and Soil-Aggregate by Nuclear Methods (Shallow Depth). g. D698 - Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Standard Effort

1.04 SUBMITTALS: A. Submit as specified in Division 01.

PART 2 - PRODUCTS

2.01 EARTHWORK: A. Materials suitable for use in and fill include material free of debris, , organic matter, and frozen matter; and free of stone having any dimension greater than 2 inches in areas requiring a high degree of compaction or 4 inches in other embankment and fill areas: 1. Cohesionless materials include , - mixtures, , and gravelly sands exclusive of clayey material: a. Free-draining.

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b. Materials for which impact compaction will not produce a -defined, moisture- density relationship curve. c. Maximum density by impact methods will generally be less than by vibratory methods. d. For which generally less than 15% by dry weight, of soil particles pass the No. 200 sieve. 2. Cohesive materials include and clays generally exclusive of sands and gravel: a. Materials for which impact compaction will produce a well-defined, moisture- density relationship curve. B. Materials unsuitable for use in embankment and fill include all material that contains debris, roots, organic matter, frozen matter, gravel, stone, or shale particles (with any dimension greater than 2 inches in areas requiring a high degree of compaction or 4 inches in other embankment and fill areas), or other materials that are determined by Engineer to be too wet or otherwise unsuitable for providing a stable or stable for structures. C. Material for Embankment or Fill: 1. Borrow materials shall meet the requirements specified in Section 312020 – Excavation and Backfill. 2. For soils used below structural elements, such as footings, slabs, and mats. See General Notes on structural drawings. D. shall be stone or hard shale found in excavations in original ledge or in pieces equal to or larger than 9 ft.3, which cannot be broken or removed by means other than, drilling and wedging. E. Waste materials include excess usable materials and materials unsuitable for use in the Work, in accordance with Paragraph 3.02A.7. F. Borrow materials include all fill materials and obtained from locations off the Site: 1. Material shall be subject to approval of Design Professional. 2. Borrow areas shall be as follows: a. Arranged for by Contractor at no additional cost to Owner. b. Subject to approval of Design Professionals. G. Bedding material shall conform to the related specifications for trenching.

PART 3 - EXECUTION

3.01 SITE PREPARATION: A. Clearing and Grubbing: 1. Perform clearing and grubbing as indicated or as necessary to perform excavation, trenching, embankment, borrow, and other work required, and where desired by Contractor for subsidiary purposes subject to approval: a. Clearing: (1) Includes felling and disposal of trees, brush, and other vegetation. (2) Conduct Work in a manner to prevent damage to property and to provide for the safety of employees and others. (3) Keep operations within property lines as indicated. b. Grubbing: (1) Includes removal and disposal of tree stumps and roots larger than 1 inch in diameter. (2) Remove to a depth of at least 18 inches below existing elevation. See structural drawing notes for excavation and removals in new building foundation areas. (3) Backfill all excavated depressions with approved material and grade to drain.

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B. Protection of Trees: 1. Protect tops, trunks, and roots of existing trees on Project Site which are to remain, as follows: a. Box, fence around, or otherwise protect trees before any work is started. b. Do not permit or stockpiles within branch spread. c. Trim or prune to obtain working space in lieu of complete removal when possible. Conduct operation as follows: (1) With experienced personnel and with approval of KC Aviation Department. (2) Conform to good horticultural practice. (3) Preserve natural shape and character. (4) Protect cuts with approved tree paint. d. Grade around trees as follows: (1) Trenching: Where trenching is required around trees which are to remain, avoid cutting the tree roots by careful hand tunneling under or around the roots. Avoid injury to or prolonged exposure of roots. (2) Raising Grades: Where existing grade at a tree is below the new finished grade and fill not exceeding 16 inches is required, place 1 to 2 inches of clean, washed gravel directly around the tree trunk. Extend gravel out from trunk on all sides at least 18 inches and finish 2 inches above finished grade at tree. Install gravel before fill is placed. Do not leave new earth fill in contact with any tree trunks. (3) Lowering Grades: Regrade by hand to elevation required around existing trees in areas where new finished grade is to be lower. As required, the roots cleanly 3 inches below finished grade, and cover scars with tree paint. e. Contact Construction Manager when damage occurs and survival is doubtful. f. Replace with similar item in species and diameter when damaged through carelessness and so requested. C. Demolition: 1. General Requirements: a. Remove existing construction to limits indicated or as required to perform new construction. Remove materials from Site, or store and reuse as specified or as indicated. b. Included (but not limited to) are: (1) Fences. (2) Ducts light pole bases. (3) Other items on Sheet C101 Demolition. 2. Protection of Existing Structure and Property: a. Perform demolition work to ensure existing structure or property which is to remain against damage from operations, falling debris, or other causes. b. Take precautions to guard against movement or settlement; use sheeting and bracing where required by the Specifications or Drawings and where resulting slopes from excavation or trenching might endanger structures or utilities. c. If at any time safety of existing structure to remain is endangered, cease operations and notify Engineer. Do not resume operation prior to approval. D. Stripping: 1. Remove topsoil from areas within limits of excavation, trenching, and borrow and areas designated to receive embankment and compacted fill as follows: a. Scrape areas clean of all brush, grass, weeds, roots, and other materials.

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b. Strip to depth of approximately 6 inches or to a sufficient depth to remove excessive roots in heavy vegetation or brush areas and as required to segregate topsoil. c. Stockpile topsoil in areas designated where it will not interfere with construction operations or existing facilities. Stockpiled topsoil shall be reasonably free of , debris, and stones larger than 2 inch diameter. E. Debris: 1. Dispose of debris from clearing, grubbing, stripping, and demolition at a location off the Site as arranged for by Contractor or by burying on the Site with approval. 2. Contractor may claim and salvage any timber which Contractor may consider of value, but shall not delay in any manner either this Contract or other work with salvaging operations. 3. of debris on site will not be permitted.

3.02 EARTHWORK: A. Excavation: 1. Perform excavation as indicated or as required to complete the Work. 2. All materials encountered, regardless of type, character, composition, and condition thereof, shall be unclassified. Estimate quantity of various materials included prior to submitting Bid Form. Rock encountered shall be handled at no additional cost to Owner. 3. Normal materials to be excavated are earth and other materials which can be removed by power , , or other normal equipment, but not requiring the use of explosives or drills: a. If rock is encountered within the limits of the excavation, notify Engineer immediately. Do not proceed further until so instructed and measurements are made for establishing the volume of rock excavation. b. Strip rock for measurement before excavating. No rock excavated or loosened before measurement will be allowed or paid for as rock. c. NO additional payment will be made for rock excavation. 4. Blasting: Blasting will not be permitted. 5. Dewatering: a. General: (1) Confine all discharge piping and/or ditches to the available easement or to additional easement obtained by Contractor. Provide all necessary means for disposal of the water, including the obtaining of all necessary permits and of additional easement at no additional cost to Owner. (2) Control in a manner that preserves the strength of the foundation and subgrade soils, does not cause instability or raveling of the excavation slopes, and does not result in damage to existing structures. (3) Control around excavations to prevent surface water from flowing into excavation areas. (4) Drain or pump as required to continually maintain all excavations and free of water or mud from any source, and discharge to approved drains or channels. Commence when water first appears and continue until Work is complete to the extent that no damage will result from hydrostatic pressure, flotation, or other causes. (5) No additional payment will be made for any supplemental measures to control seepage, groundwater, or artesian head. b. Damages: (1) Remove subgrade materials rendered unsuitable by excessive wetting and replace with approved backfill material at no additional cost to Owner.

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c. Maintaining Excavation in Dewatered Condition: (1) Continuously maintain excavation in a dry condition with positive dewatering methods during preparation of subgrade, installation of pipe, and construction of structures until the critical period of construction and/or backfill is completed to prevent damage of subgrade support, piping, structure, side slopes, or adjacent facilities from flotation or other hydrostatic pressure imbalance. 6. Stockpiling: a. Stockpile in amounts sufficient for and in a manner to segregate materials suitable for the following: (1) Topsoiling. (2) Constructing embankments and fills. (3) Backfilling. b. Do not obstruct or prevent access to: (1) and driveways. (2) Utility control devices. (3) Ditches or natural drainage channels. c. Maintain safe distance between toe of stockpile and edge of excavation or . d. Stockpile in other areas or off site when adjacent structures, easement limitations, or other restrictions prohibit sufficient storage adjacent to the Work. Off-Site areas shall be arranged for by Contractor at no additional cost to Owner. 7. Waste Materials: a. Waste materials as described for purposes of this Contract within this Section consist of deleterious soils, rock, and other materials considered unacceptable for compaction or placement fill, and which are not environmentally contaminated. Waste materials shall not include environmental pollutants, hazardous substances, contaminated products, byproducts, samples, or waste materials of any kind that are regulated under environmental laws. b. Remove waste materials from Work area as excavated. c. Material shall become property of Contractor and shall be disposed of off-site at locations arranged for by Contractor. d. Grade waste areas and leave them free draining and with an orderly and neat appearance. B. Embankment: 1. Construct embankments to the contours and elevations indicated, using suitable approved material from excavations and borrow areas: a. Borrow: (1) Refers to all fill materials and topsoil obtained from approved locations off the Site. (2) Borrow shall include all excavating, handling, and final disposal of materials as specified. (3) Borrow areas shall be: (a) Arranged for by Contractor at no additional cost to Owner. (b) Subject to approval. (4) Material removed from borrow areas shall be as approved. (5) Leave borrow areas graded to drain and to present a neat appearance. b. Compaction: (1) Compact embankments using equipment as required to obtain reasonable uniformity. (2) Except as indicated otherwise, compact embankments to 95% of maximum dry density within the moisture content range from 0% below optimum to 4%

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above optimum. Optimum moisture and maximum density shall be as determined by AASHTO T 99, ASTM D698. (3) Compaction shall be as obtained by normal methods and equipment during the placing and grading of layers and to the minimum density specified for particular locations. (4) Moisture content shall be that required to obtain specified compaction of the soil: (a) Perform moisture curing by wetting or drying of the material as required to attain required compaction criteria. (5) Achieve minimum densities specified. c. Placement: (1) Place fill material in 8-inch layers. (2) Place embankment only on subgrades approved by Engineer. (3) Do not place snow, ice, or frozen earth in fill; do not place fill on a frozen surface. C. Subgrades: 1. General: a. Excavate or fill as required to construct subgrades to the elevations and grades indicated. b. Remove all unsuitable material and replace with approved fill materials. c. Perform all wetting, drying, shaping, and compacting required to prepare a suitable subgrade. d. Apply flyash as specified in related paving specifications. e. Exposed area to receive fill, backfill, or embankment shall be proofrolled to detect localized zones of excessively wet, unstable, organic, or low materials to the extent as follows: (1) Proofroll within limits of proposed construction of foundations, slabs, mats, or pavements and to extent of 10 ft. beyond the proposed exterior walls and stated limits, or as otherwise noted. Proofroll with tandem-axle loaded dump truck, loaded pan scrapper, 20-ton light class pneumatic tired roller compactor, or equivalent. Ground contact pressure of 80 psi with average speed of 5 miles per hour shall be maintained and continue until extent of soft spots is determined with not less than one pass per unit area of tire. Soft spots shall be over-excavated, backfilled, and compacted with suitable material. 2. Subgrade for Fills and Embankment: Roughen by discing or scarifying. Wet or dry top 6 inches, as required, to bond with fill or embankment. 3. Subgrade for Roadways, Drives, Parking Areas, shall be as specified in related paving specifications: a. Subgrades shall be rolled (except those to receive aggregate- type surfacing). 4. Subgrades for Concrete Slabs on Grade: a. Compact cohesive soil subgrades in embankment areas and in the top 12 inches in excavation areas to 95% of maximum dry density within the moisture content range from 0% below optimum to 4% above optimum. Optimum moisture and maximum dry density shall be determined by AASHTO T199/ASTM D698. b. Where subgrade consists of cohesionless granular materials, compact to 70 % relative density as determined by ASTM D4253 and D4254. D. Site Grading: 1. Excavate, fill, compact fill, and rough grade to bring Project area outside of buildings to subgrades as follows: a. For surfaced areas, to underside of respective surfacing or : b. Prepare subgrades as specified in related Sections.

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c. For lawn and planted areas, to 4 inches below finished grade. 2. Rock: a. Includes rock encountered in grading areas outside of buildings. b. Excavate rock to depths as follows: (1) Under surfaced areas, to 6 inches below the top of respective subgrades. (2) Under lawn and planted areas, to 24 inches below finished grade: (a) Boulder or protruding rock outcrop shall be left undisturbed where indicated. c. Backfill to grade with approved earth fill compacted-in-place: (1) Achieve minimum density specified for particular location. 3. Fill: a. Fill as required to raise existing grades outside of building areas to the new grades as indicated. b. Such fill shall be performed as specified in PART 3, paragraph 3.02B - Embankment, this Section. c. Remove all debris subject to termite attack, rot, or corrosion from areas to be filled. 4. Rough Grading: a. All areas within the Project, including excavated and filled sections, and adjacent transition areas shall be reasonably smooth, compacted, and free from irregular surface changes. b. Degree of finish shall be that ordinarily obtained from blade grader or scraper operations, except as otherwise specified. c. Finished rough grades shall generally be not more than 0.5 ft. above or below established grade or approved cross sections with due allowance for topsoil and sod. d. Tolerance for areas within 10 ft. of building and areas to be paved shall not exceed 0.15 ft. above or below established subgrade. Finish all ditches, swales, and gutters to drain readily. e. Finish all ditches, swales, and gutters to drain readily. f. Unless otherwise indicated, slope the subgrade evenly to provide drainage away from building walls in all directions at a grade not less than 1/4 inch per foot. g. Provide roundings at top and bottom of banks and at other breaks in grade. E. Topsoiling: 1. Includes placement of topsoil on all areas not specified to receive paving or other surface treatment (including borrow or waste areas). 2. Materials: a. Those obtained from excavation which are most suitable and stockpiles for such purpose: (1) Topsoil shall be a fertile, friable, and loamy soil of uniform quality, free from materials such as hard clods, stiff , stone with any dimension greater than 1 inch, and similar impurities. Relatively free from grass, roots, weeds, and other objectionable plant material. b. Borrow when required. 3. Subgrade Treatment: a. Clear Site of vegetation heavy enough to interfere with proper grading and tillage operations. b. Clear surfaces of all stones or other objects larger than 3 inches in thickness or diameter, all roots, brush, wire, grade stakes, or other objectionable material. c. Loosen subgrade by discing or scarifying to a depth of 2 inches wherever compacted by traffic or other causes to permit bonding of the topsoil to the subgrade.

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4. Placement of Topsoil: a. Distribute over required areas without compaction in upper 1 ft., other than that obtained with spreading equipment. b. To extent material is available within following limits: (1) Not less than 4 inches in depth. (2) Do not exceed 2 ft. in depth. (3) Shape cuts, fills, and embankments to contours indicated. (4) Grade to match contours of adjacent areas and permit good, natural drainage. Provide gentle mound over trenches. 5. Maintenance: a. After topsoil has been spread, clear surface of stones or other objects larger than 1 inch in thickness or diameter and all other objects that might interfere with planting and maintenance operations. b. Protect topsoiled areas from the elements until grass is established and repair eroded areas as required. c. Keep paved areas clean. Promptly remove topsoil or other dirt dropped upon surfacing.

3.03 FIELD QUALITY CONTROL: A. Compaction: 1. Contractor will, through services of an independent laboratory, test all embankments, fills, and subgrades under this Contract to determine conformance with specified density relationships. 2. Method of test may be either of the following at Design Professional's option: a. ASTM D2167. b. ASTM D6938. 3. The frequency of tests will be in compliance with KCMO requirements (or as otherwise required by Owner). B. Subgrades: 1. Engineer will inspect all subgrades to determine conformance with indicated lines and grades. 2. Subgrades for roadways, drives, parking areas, and railroads shall have a maximum deviation of not more than 1/2 inch in any 10 ft. when tested with a 10-ft. straightedge applied parallel with and at right angles to the centerlines of subgrade areas, except that subgrades to receive aggregate-type surfacing shall have a maximum deviation of not more than 1 inch in any 10 ft.

3.04 PROTECTION OF THE WORK: A. Maintenance: 1. Protect newly graded and topsoiled areas from actions of the elements. 2. Fill and repair settling or erosion occurring prior to landscaping and reestablish grades to the required elevations and slopes. B. Correction of Backfill Settlement: 1. Under provisions of the guarantee, Contractor is responsible for correcting any settlement of backfill and damages created thereby within 1 year after acceptance of the Work. 2. Make repairs within 10 days from and after due notification by Owner of backfill settlement and resulting damage. 3. Make own arrangements for access to the Site for purposes of repair.

END OF SECTION 312000

312000 SITE PREPARATION AND EARTHWORK 312000 - 8 SECTION 312020 - EXCAVATION AND BACKFILL

PART 1 - GENERAL

1.01 RELATED DOCUMENTS: A. Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 01 Specification Sections, apply to this Section.

1.02 SUMMARY: A. This Section includes: 1. Preparing subgrades for slabs-on-grade, building foundations, turf and grasses, and, plants. 2. Excavating and backfilling for buildings and structures. 3. Drainage course for concrete slabs-on-grade. 4. Subsurface drainage backfill for walls and trenches. 5. Excavating and backfilling trenches for utilities and pits for buried utility structures. B. Related Sections: 1. Division 01, Section "Construction Progress Documentation or Photographic Documentation" for recording pre-excavation and earth moving progress. 2. Division 01, Section "Temporary Facilities and Controls" for temporary controls, utilities, and support facilities; also for temporary site fencing if not in another Section. 3. Division 03, Section "Cast-in-Place Concrete" for granular course. 4. Divisions 21, 22, 23, 26, 27, and 28 Sections for installing underground mechanical and electrical utilities and buried mechanical and electrical structures. 5. Division 31, Section "Site Preparation and Earthwork" for site stripping, grubbing, stripping, and stockpiling topsoil, and removal of above- and below-grade improvements and utilities.

1.03 DEFINITIONS: A. Backfill: Soil material or controlled low-strength material used to fill an excavation. 1. Initial Backfill: Backfill placed beside and over pipe in a trench, including haunches to support sides of pipe. 2. Final Backfill: Backfill placed over initial backfill to fill a trench. B. Bedding Course: Aggregate layer placed over the excavated subgrade in a trench before laying pipe. C. Borrow Soil: Satisfactory soil as defined in Geotechnical report imported from off-site for use as fill or backfill. D. Drainage Course: Aggregate layer supporting the slab-on-grade that also minimizes upward capillary flow of pore water. E. Excavation: Removal of material encountered above subgrade elevations and to lines and dimensions indicated. 1. Authorized Additional Excavation: Excavation below subgrade elevations or beyond indicated lines and dimensions as directed by Kansas City Aviation Department (KCAD) Representative. Authorized additional excavation and replacement material will be paid for according to Contract provisions for changes in the Work. 2. Unauthorized Excavation: Excavation below subgrade elevations or beyond indicated lines and dimensions without direction by KCAD Representative. Unauthorized excavation, as well as remedial work directed by KCAD Representative, shall be without additional compensation. F. Fill: Soil materials used to raise existing grades.

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G. Engineered Fill: Naturally or artificially graded mixture of natural and crushed gravel as defined in the specification. H. Rock: Rock material in beds, ledges, unstratified masses, conglomerate deposits, and boulders of rock material that exceed 1 cu. yd. for bulk excavation or 3/4 cu. yd. for footing, trench, and pit excavation that cannot be removed by rock excavating equipment equivalent to the following in size and performance ratings, without systematic drilling, ram hammering, ripping, or blasting, when permitted: 1. Excavation of Footings, Trenches, and Pits: Late-model, track-mounted hydraulic ; equipped with a 42-inch wide, maximum, short-tip-radius rock bucket; rated at not less than 138-hp flywheel power with bucket-curling force of not less than 28,700 lbf and stick-crowd force of not less than 18,400 lbf with extra-long reach boom; measured according to SAE J-1179. 2. Bulk Excavation: Late-model, track-mounted ; rated at not less than 230-hp flywheel power and developing a minimum of 47,992-lbf breakout force with a general- purpose bare bucket; measured according to SAE J-732. I. Structures: Buildings, footings, foundations, retaining walls, slabs, tanks, curbs, mechanical and electrical appurtenances, or other man-made stationary features constructed above or below the ground surface. J. Utilities: On-site underground pipes, conduits, ducts, and cables, as well as underground services within buildings.

1.04 ACTION SUBMITTALS: A. Product Data: For each type of the following manufactured products required: 1. . 2. Controlled low-strength material, including design mixture. 3. Warning tapes. 4. Fill. 5. Borrow. B. Samples for Verification: For the following products, in sizes indicated below: 1. : 12 by 12 inches.

1.05 INFORMATIONAL SUBMITTALS: A. Qualification Data: For qualified testing agency. B. Material Test Reports: For each borrow soil material proposed for fill and backfill as follows: 1. Classification according to ASTM D2487. 2. Laboratory compaction curve according to ASTM D698. C. Blasting not allowed on this project. D. Pre-excavation Photographs or Videotape: Show existing conditions of adjoining construction and site improvements, including finish surfaces, which might be misconstrued as damage caused by earth moving operations. Submit before earth moving begins.

1.06 QUALITY ASSURANCE: A. Geotechnical Testing Agency Qualifications: Qualified according to ASTM E329 and ASTM D3740 for testing indicated. 1. Sampling and Testing: a. Contractor will, through the services of an independent, commercial laboratory, perform all testing of Owner-furnished materials. b. Tests to determine conformance with all requirements of this specification for quality and properties of all Contractor-secured materials, including borrow materials (both on or off-site) proposed for use, shall be performed by an

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independent, commercial laboratory retained and compensated by Contractor, and approved by Design Professional. c. When incorporating materials into the Work, quality control testing will be performed during construction by a testing laboratory retained and compensated by the Contractor. B. Pre-excavation Conference: Conduct conference at Project Site.

1.07 PROJECT CONDITIONS: A. Traffic: Minimize interference with adjoining roads, streets, walks, and other adjacent occupied or used facilities during earth moving operations. 1. Do not close or obstruct streets, walks, or other adjacent occupied or used facilities without permission from Owner and authorities having jurisdiction. 2. Provide alternate routes around closed or obstructed traffic ways if required by Owner or authorities having jurisdiction. B. Utility Locator Service: Notify Missouri One-Call and KC Aviation Department for area where Project is located before beginning earth moving operations. C. Do not commence earth moving operations until temporary erosion- and sedimentation-control measures, specified in Division 01, Section "Temporary Facilities and Controls," Division 31, Section "Site Preparation and Earthwork," and on Sediment and Plans and approved SWPPP are in place. D. Do not commence earth moving operations until plant-protection measures specified in Division 31, Section "Site Preparation and Earthwork" are in place. E. The following practices are prohibited within protection zones: 1. Storage of construction materials, debris, or excavated material. 2. Parking vehicles or equipment. 3. Foot traffic. 4. Erection of sheds or structures. 5. Impoundment of water. 6. Excavation or other unless otherwise indicated. 7. Attachment of signs to or wrapping materials around trees or plants unless otherwise indicated. F. Do not direct vehicle or equipment exhaust towards protection zones. G. Prohibit heat sources, flames, ignition sources, and smoking within or near protection zones.

PART 2 - PRODUCTION

2.01 SOIL MATERIALS: A. General: Provide borrow soil materials when sufficient satisfactory soil materials are not available from excavations. B. Satisfactory Soils: Groups CL, CL-ML, and GW according to ASTM D2487 free of rock or gravel larger than 2 inches in any dimension, debris, waste, frozen materials, vegetation, and other deleterious matter. 1. Liquid Limit: < 45%. 2. Plasticity Index: < 25%. C. Unsatisfactory Soils: Soil Classification Groups not listed as satisfactory. 1. Unsatisfactory soils also include satisfactory soils not maintained within zero to +4% of optimum moisture content for fine-grained soils and pavement subgrade at time of compaction. D. Engineered Fill: Naturally or artificially graded mixture of natural or crushed gravel, , and natural or crushed sand; ASTM D2940; with at least 90% passing a 1-1/2-inch sieve and not more than 12% passing a No. 200 sieve. Soil Classification Groups CL, CL-ML, and

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GW according to ASTM D2487, free of rock or gravel larger than 2 inches in any dimension, debris, waste, frozen materials, vegetation, and other deleterious matter. 1. Liquid: <45% 2. Plastic Limit: <25% E. Bedding Course: Naturally or artificially graded mixture of natural or crushed gravel, crushed stone, and natural or crushed sand; ASTM D2940; except with 100% passing a 1-inch sieve and not more than 8% passing a No. 200 sieve. F. Drainage Course: Narrowly graded mixture of washed crushed stone, or crushed or uncrushed gravel; ASTM D448; coarse-aggregate grading Size 57; with 100% passing a 1-1/2-inch sieve and 0 to 5% passing a No. 8 sieve. G. Filter Material: Narrowly graded mixture of natural or crushed gravel, or crushed stone and natural sand; ASTM D448; coarse-aggregate grading Size 67; with 100% passing a 1-inch sieve and 0 to 5% passing a No. 4 sieve. H. Impervious Fill: Clayey gravel and sand mixture capable of compacting to a dense state.

2.02 GEOTEXTILES: A. Subsurface Drainage Geotextile: Nonwoven needle-punched geotextile, manufactured for subsurface drainage applications, made from polyolefins or polyesters; with elongation greater than 50%; complying with AASHTO M 288 and the following, measured per test methods referenced: 1. Survivability: Class 2; AASHTO M 288. 2. Grab Tensile Strength: 157 lbf; ASTM D4632. 3. Sewn Seam Strength: 142 lbf; ASTM D4632. 4. Tear Strength: 56 lbf; ASTM D4533. 5. Puncture Strength: 56 lbf; ASTM D4833. 6. Apparent Opening Size: No. 70 sieve, maximum; ASTM D4751. 7. Permittivity: 0.2 per second, minimum; ASTM D4491. 8. UV Stability: 50% after 500 hours' exposure; ASTM D4355. B. Separation Geotextile: Woven geotextile fabric, manufactured for separation applications, made from polyolefins or polyesters; with elongation less than 50%; complying with AASHTO M 288 and the following, measured per test methods referenced: 1. Survivability: Class 2; AASHTO M 288. 2. Grab Tensile Strength: 247 lbf; ASTM D4632. 3. Sewn Seam Strength: 222 lbf; ASTM D4632. 4. Tear Strength: 90 lbf; ASTM D4533. 5. Puncture Strength: 90 lbf; ASTM D4833. 6. Apparent Opening Size: No. 60 sieve, maximum; ASTM D4751. 7. Permittivity: 0.02 per second, minimum; ASTM D4491. 8. UV Stability: 50% after 500 hours' exposure; ASTM D4355.

2.03 CONTROLLED LOW-STRENGTH MATERIAL: A. Controlled Low-Strength Material: Self-compacting, flowable concrete material produced from the following: 1. Portland Cement: ASTM C150, Type I or Type II. 2. Fly Ash: ASTM C618, Class C. 3. Normal-Weight Aggregate: ASTM C33, 3/4-inch nominal maximum aggregate size. 4. Foaming Agent: ASTM C869. 5. Water: ASTM C94/C94M. 6. Air-Entraining Admixture: ASTM C260. B. Produce low-density, controlled low-strength material with the following physical properties:

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1. As-Cast Unit Weight: 36 to 42 lb./cu. ft. at point of placement, when tested according to ASTM C138/C 138M. 2. Compressive Strength: 200 psi when tested according to ASTM C495. C. Produce conventional-weight, controlled low-strength material with 200 psi compressive strength when tested according to ASTM C39.

2.04 ACCESSORIES: A. Detectable Warning Tape: Acid- and alkali-resistant, polyethylene film warning tape manufactured for marking and identifying underground utilities, a minimum of 6 inches wide and 4 mils thick, continuously inscribed with a description of the utility, with metallic core encased in a protective jacket for corrosion protection, detectable by metal detector when tape is buried up to 30 inches deep; colored as follows: 1. Red: Electric. 2. Yellow: Gas, oil, steam, and dangerous materials. 3. Orange: Telephone and other communications. 4. Blue: Water systems. 5. Green: Sewer systems.

PART 3 - EXECUTION

3.01 PREPARATION: A. Protect structures, utilities, sidewalks, pavements, and other facilities from damage caused by settlement, lateral movement, undermining, washout, and other hazards created by earth moving operations. B. Protect and maintain erosion and sedimentation controls during earth moving operations. C. Protect subgrades and foundation soils from freezing temperatures and frost. Remove temporary protection before placing subsequent materials.

3.02 DEWATERING: A. Prevent surface water and ground water from entering excavations, from ponding on prepared subgrades, and from flooding Project Site and surrounding area. B. Protect subgrades from softening, undermining, washout, and damage by rain or water accumulation. 1. Reroute surface water runoff away from excavated areas. Do not allow water to accumulate in excavations. Do not use excavated trenches as temporary drainage ditches.

3.03 EXPLOSIVES: A. Explosives: Do not use explosives.

3.04 EXCAVATION, GENERAL: A. Unclassified Excavation: Excavate to subgrade elevations regardless of the character of surface and subsurface conditions encountered. Unclassified excavated materials may include rock, soil materials, and obstructions. No changes in the Contract Sum or the Contract Time will be authorized for rock excavation or removal of obstructions. 1. If excavated materials intended for fill and backfill include unsatisfactory soil materials and rock, replace with satisfactory soil materials. 2. Remove rock to lines and grades indicated to permit installation of permanent construction without exceeding the following dimensions: a. 24 inches outside of concrete forms other than at footings. b. 6 inches outside of minimum required dimensions of concrete cast against grade.

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c. Outside dimensions of concrete walls indicated to be cast against rock without forms or exterior waterproofing treatments. d. 6 inches beneath bottom of concrete slabs-on-grade. e. 6 inches beneath pipe in trenches, and the greater of 24 inches wider than pipe or 42 inches wide.

3.05 EXCAVATION FOR STRUCTURES: A. Excavate to indicated elevations and dimensions within a tolerance of ±1 inch. If applicable, extend excavations a sufficient distance from structures for placing and removing concrete formwork, for installing services and other construction, and for inspections. 1. Excavations for Building Slab: High plastic clay within at least 24 inches of building floor slab subgrade shall be excavated and replaced with fill Engineered Fill. 2. Excavations for Footings and Foundations: a. Base Bid Footing Foundations: (1) Excavations shall extend to 2-ft. below the bottom of planned footing elevation and the bottom width of the excavation shall be twice the footing width as indicated on the drawings. (2) Excavations shall be backfilled with unreinforced lean concrete to footing bearing elevations. (3) Excavation and backfilling process should be completed within the same working day. b. Excavate by hand to final grade just before placing concrete reinforcement. Trim bottoms to required lines and grades to leave solid base to receive other work. 3. Excavation for Underground Tanks, Basins, and Mechanical or Electrical Utility Structures: Excavate to elevations and dimensions indicated within a tolerance of plus or minus 1 inch. Do not disturb bottom of excavations intended as bearing surfaces. B. Excavations at Edges of Tree- and Plant-Protection Zones: 1. Excavate by hand to indicated lines, cross sections, elevations, and subgrades. Use narrow-tine spading forks to comb soil and expose roots. Do not break, tear, or chop exposed roots. Do not use mechanical equipment that rips, tears, or pulls roots. 2. Cut and protect roots according to requirements in Division 31, Section "Site Preparation and Earthwork."

3.06 EXCAVATION FOR WALKS AND PAVEMENTS: A. Excavate surfaces under walks and pavements to indicated lines, cross sections, elevations, and subgrades.

3.07 EXCAVATION FOR UTILITY TRENCHES: A. Using GIS, locate beginning and end point of utility alignments installed; include interim locations at major alignment changes. Provide data to KCAD Representative and Design Professional. B. Excavate trenches to indicated gradients, lines, depths, and elevations. 1. Beyond building perimeter, excavate trenches to allow installation of top of pipe below frost line. C. Excavate trenches to uniform widths to provide the following clearance on each side of pipe or conduit. Excavate trench walls vertically from trench bottom to 12 inches higher than top of pipe or conduit unless otherwise indicated. D. Trench Bottoms: Excavate and shape trench bottoms to provide uniform bearing and support of pipes and conduit. Shape subgrade to provide continuous support for bells, joints, and barrels of pipes and for joints, fittings, and bodies of conduits. Remove projecting stones and sharp objects along trench subgrade.

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1. For pipes and conduit less than 6 inches in nominal diameter, hand-excavate trench bottoms and support pipe and conduit on an undisturbed subgrade. 2. For pipes and conduit 6 inches or larger in nominal diameter, shape bottom of trench to support bottom 90 degrees of pipe or conduit circumference. Fill depressions with tamped sand backfill. 3. For flat-bottomed, multiple-duct conduit units, hand-excavate trench bottoms and support conduit on an undisturbed subgrade. 4. Excavate trenches 6 inches deeper than elevation required in rock or other unyielding bearing material to allow for bedding course. E. Trench Bottoms: Excavate trenches 6 inches deeper than bottom of pipe and conduit elevations to allow for bedding course. Hand-excavate deeper for bells of pipe. 1. Excavate trenches 6 inches deeper than elevation required in rock or other unyielding bearing material to allow for bedding course. F. Trenches in Tree- and Plant-Protection Zones: 1. Hand-excavate to indicated lines, cross sections, elevations, and subgrades. Use narrow- tine spading forks to comb soil and expose roots. Do not break, tear, or chop exposed roots. Do not use mechanical equipment that rips, tears, or pulls roots. 2. Do not cut main lateral roots or taproots; cut only smaller roots that interfere with installation of utilities. 3. Cut and protect roots according to requirements in Division 31, Section "Site Preparation and Earthwork."

3.08 SUBGRADE INSPECTION: A. See paving specifications for paving subgrades. B. Foundation Subgrade: Excavate or backfill as required to construct subgrades to elevations and grades indicated. 1. Remove all unsuitable material and replace with acceptable fill material and perform all wet-ting, drying, shaping, and compacting required to prepare subgrade. Proofrolling: Exposed area to receive fill, backfill, or embankment shall be proofrolled to detect localized zones of excessively wet, unstable, organic, or low bearing capacity materials as follows: a. Proofroll as a single-pass operation with conventional compaction equipment during sub-grade preparation and prior to placement of fill, and as a spot check process without the need for complete coverage per unit area of tire. Soft spots shall be over-excavated, backfilled, and compacted with suitable material. b. Proofroll within limits of proposed construction of footings, slabs, mats, or pavement and to extent of 10 feet beyond proposed exterior walls and stated limits, or as otherwise noted. c. Proofroll with loaded tandem-axle dump truck, loaded pan scrapper, 20-ton light class pneumatic tired roller compactor, or equivalent. Ground contact pressure of 80 psi and average speed of 5 miles per hour shall be maintained and continue until ex-tent of soft spots is determined with not less than one pass per unit area of tire. Soft spots shall be over-excavated, backfilled, and compacted with suitable material. 2. Subgrade for Fills and Embankments: Roughen by discing or scarifying and wet or dry top 6 inches as required to bond with fill or embankment. 3. Compact cohesive soil subgrades to a minimum of 95% of maximum dry density within the moisture content range from 0% below optimum to 4% above optimum. Optimum moisture and maximum dry density shall be determined by ASTM D698 (ASTM D1557).

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3.09 UNAUTHORIZED EXCAVATION: A. Fill unauthorized excavation under foundations or wall footings by extending bottom elevation of concrete foundation or footing to excavation bottom, without altering top elevation. Lean concrete fill, with 28-day compressive strength of 2,500 psi may be used when approved by KCAD Representative. 1. Fill unauthorized excavations under other construction, pipe, or conduit as directed by KCAD Representative.

3.10 STORAGE OF SOIL MATERIALS: A. Stockpile borrow soil materials and excavated satisfactory soil materials without intermixing. Place, grade, and shape stockpiles to drain surface water. Cover to prevent windblown dust. 1. Stockpile soil materials away from edge of excavations. Do not store within drip line of remaining trees. 2. Protect stockpile in accordance with SWPPP for Site.

3.11 BACKFILL: A. Place and compact backfill in excavations promptly, but not before completing the following: 1. Construction below finish grade including, where applicable, subdrainage, dampproofing, waterproofing, and perimeter insulation. 2. Surveying locations of underground utilities for Record Documents. 3. Testing and inspecting underground utilities. 4. Removing concrete formwork. 5. Removing trash and debris. 6. Removing temporary shoring and bracing, and sheeting. 7. Installing permanent or temporary horizontal bracing on horizontally supported walls. B. Place backfill on subgrades free of mud, frost, snow, or ice.

3.12 UTILITY TRENCH BACKFILL: A. Place backfill on subgrades free of mud, frost, snow, or ice. B. Place and compact bedding course on trench bottoms and where indicated. Shape bedding course to provide continuous support for bells, joints, and barrels of pipes and for joints, fittings, and bodies of conduits. C. Trenches under Footings: Backfill trenches excavated under footings and within 18 inches of bottom of footings with engineered fill; fill with concrete to elevation of bottom of footings. Concrete is specified in Division 03, Section "Cast-in-Place Concrete." D. Trenches under Roadways: Provide 4-inch thick, concrete-base slab support for piping or conduit less than 30 inches below surface of roadways. After installing and testing, completely encase piping or conduit in a minimum of 4 inches of concrete before backfilling or placing roadway subbase course if encasement is defined on plans. Concrete is specified in related utility specification. E. Backfill voids with satisfactory soil while removing shoring and bracing. F. Place and compact initial backfill of satisfactory soil, free of particles larger than 1 inch in any dimension, to a height of 12 inches over the pipe or conduit. 1. Carefully compact initial backfill under pipe haunches and compact evenly up on both sides and along the full length of piping or conduit to avoid damage or displacement of piping or conduit. Coordinate backfilling with utilities testing. G. Controlled Low-Strength Material: Place initial backfill of controlled low-strength material to a height of 12 inches over the pipe or conduit if CLSM is specified on plans. Coordinate backfilling with utilities testing. H. Place and compact final backfill of satisfactory soil to final subgrade elevation.

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I. Controlled Low-Strength Material: Place final backfill of controlled low-strength material to final subgrade elevation. J. Install warning tape or 3M Marker Ball directly above utilities (signal side up), 12 inches below finished grade, except 6 inches below subgrade under pavements and slabs.

3.13 SOIL FILL: A. Plow, scarify, bench, or break up sloped surfaces steeper than 1 vertical to 4 horizontal so fill material will bond with existing material. B. Place and compact fill material in layers to required elevations as follows: 1. Under grass and planted areas, use satisfactory soil material. 2. Under walks and pavements, use satisfactory soil material. 3. Under steps and ramps, use engineered fill. 4. Under building slabs, use engineered fill. 5. Under footings and foundations, use engineered fill. C. Place soil fill on subgrades free of mud, frost, snow, or ice.

3.14 SOIL MOISTURE CONTROL: A. Uniformly moisten or aerate subgrade and each subsequent fill or backfill soil layer before compaction to within zero to +4% of optimum moisture content for fine-grained soils. 1. Do not place backfill or fill soil material on surfaces that are muddy, frozen, or contain frost or ice. 2. Remove and replace, or scarify and air dry, otherwise satisfactory soil material that exceeds optimum moisture content by 4% (for fine-grained soils) and is too wet to compact to specified dry unit weight.

3.15 COMPACTION OF SOIL BACKFILLS AND FILLS: A. Place backfill and fill soil materials in layers not more than 8 inches in loose depth for material compacted by heavy compaction equipment, and not more than 4 inches in loose depth for material compacted by hand-operated tampers. B. Place backfill and fill soil materials evenly on all sides of structures to required elevations, and uniformly along the full length of each structure. C. Compact soil materials to not less than the following percentages of maximum dry unit weight according to ASTM D698: 1. Under structures, building slabs, steps, and pavements, scarify and recompact top 6 inches of existing subgrade and each layer of backfill or fill soil material at 95% Standard Proctor. 2. Under walkways, scarify and recompact top 6 inches below subgrade and compact each layer of backfill or fill soil material at 95%. 3. Under turf or unpaved areas, scarify and recompact top 6 inches below subgrade and compact each layer of backfill or fill soil material at 90%. 4. For utility trenches, compact each layer of initial and final backfill soil material at 95%.

3.16 GRADING: A. General: Uniformly grade areas to a smooth surface, free of irregular surface changes. Comply with compaction requirements and grade to cross sections, lines, and elevations indicated. 1. Provide a smooth transition between adjacent existing grades and new grades. 2. Cut out soft spots, fill low spots, and trim high spots to comply with required surface tolerances.

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B. Site Rough Grading: Slope grades to direct water away from buildings and to prevent ponding. Finish subgrades to required elevations within the following tolerances: 1. Turf or Unpaved Areas: ±1 inch. 2. Walks: ±1 inch. 3. Pavements: ±1/2 inch. C. Grading inside Building Lines: Finish subgrade to a tolerance of 1/2 inch when tested with a 10-foot straightedge.

3.17 SUBSURFACE DRAINAGE: A. Subdrainage Pipe: Specified in Division 22, Section "Facility Storm Drainage Piping." B. Subsurface Drain: Place subsurface drainage geotextile around perimeter of subdrainage trench. Place a 6-inch course of filter material on subsurface drainage geotextile to support subdrainage pipe. Encase subdrainage pipe in a minimum of 12 inches of filter material, placed in compacted layers 6 inches thick, and wrap in subsurface drainage geotextile, overlapping sides and ends at least 6 inches. 1. Compact each filter material layer to 70 % of relative density as determined by ASTM D4253 and D4254. C. Drainage Backfill: Place and compact filter material over subsurface drain, in width indicated, to within 12 inches of final subgrade, in compacted layers 6 inches thick. Overlay drainage backfill with one layer of subsurface drainage geotextile, overlapping sides and ends at least 6 inches. 1. Compact each filter material layer to 70 % of relative density as determined by ASTM D4253 and D4254.

3.18 SUBBASE AND BASE COURSES UNDER PAVEMENTS AND WALKS: A. See Pavement specifications.

3.19 DRAINAGE COURSE UNDER CONCRETE SLABS-ON-GRADE: A. Place drainage course on subgrades free of mud, frost, snow, or ice. B. On prepared subgrade, place and compact drainage course under cast-in-place concrete slabs- on-grade as follows: 1. Place drainage course 6 inches or less in compacted thickness in a single layer. 2. Compact each layer of drainage course to required cross sections and thicknesses

3.20 FIELD QUALITY CONTROL: A. Special Inspections: Contractor will engage a qualified special inspector to perform the following special inspections: 1. Determine prior to placement of fill that Site has been prepared in compliance with requirements. 2. Determine that fill material and maximum lift thickness comply with requirements. 3. Determine, at the required frequency, that in-place density of compacted fill complies with requirements. B. Testing Agency: Contractor will engage a qualified independent testing agency to perform tests and inspections. C. Allow testing agency to inspect and test subgrades and each fill or backfill layer. Proceed with subsequent earth moving only after test results for previously completed work comply with requirements. D. Footing Subgrade: At footing subgrades, at least one test of each soil stratum will be performed to verify design bearing capacities. Subsequent verification and approval of other footing subgrades may be based on a visual comparison of subgrade with tested subgrade when approved by KCAD Representative.

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E. Testing agency will test compaction of soils in place according to ASTM D1556, ASTM D2167, ASTM D2922, and ASTM D2937, as applicable. Tests will be performed at the following locations and frequencies: 1. Paved and Building Slab Areas: At subgrade and at each compacted fill and backfill layer, at least one test for every 5,000 sq. ft. or less of paved area or building slab, but in no case fewer than three tests. 2. Foundation Wall Backfill: At each compacted backfill layer, at least one test for every 300 feet or less of wall length, but no fewer than two tests. 3. Trench Backfill: At each compacted initial and final backfill layer, at least one test for every 300 feet or less of trench length, but no fewer than two tests. F. When testing agency reports that subgrades, fills, or backfills have not achieved degree of compaction specified, scarify and moisten or aerate, or remove and replace soil materials to depth required; recompact and retest until specified compaction is obtained.

3.21 PROTECTION: A. Protecting Graded Areas: Protect newly graded areas from traffic, freezing, and erosion. Keep free of trash and debris. B. Repair and reestablish grades to specified tolerances where completed or partially completed surfaces become eroded, rutted, settled, or where they lose compaction due to subsequent construction operations or weather conditions. 1. Scarify or remove and replace soil material to depth as directed by KCAD Representative; reshape and recompact. C. Where settling occurs before Project correction period elapses, remove finished surfacing, backfill with additional soil material, compact, and reconstruct surfacing. 1. Restore appearance, quality, and condition of finished surfacing to match adjacent work, and eliminate evidence of restoration to greatest extent possible.

3.22 DISPOSAL OF SURPLUS AND WASTE MATERIALS: A. Remove surplus satisfactory soil and waste materials, including unsatisfactory soil, trash, and debris, and legally dispose of them off Owner's property. B. Transport surplus satisfactory soil to designated storage areas on Owner's property. Stockpile or spread soil as directed by KCAD Representative. 1. Remove waste materials, including unsatisfactory soil, trash, and debris, and legally dispose of them off Owner's property.

END OF SECTION 312020

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