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9/2/2020 <br /> <br />31 20 00 EARTH MOVING Page 10 of 13 <br />F. Warning Tape: Install warning tape directly above utilities, 12 inchesbelow finished grade, except <br />6 inchesbelow subgrade under pavements and slabs. <br />3.13 SOIL FILL <br />A. Plow, scarify, bench, or break up sloped surfaces steeper than 1 vertical to 4 horizontal so fill <br />material will bond with existing material. <br />B. Place and compact fill material in layers to required elevations as follows: <br />1. Under grass and planted areas, use satisfactory soil material. <br />2. Under walks and pavements, use satisfactory soil material. <br />3. Under steps and ramps, use Aggregate Base Course <br />4. Under building slabs, use Aggregate Base Course <br />5. Under footings and foundations, use satisfactory soil material <br />C. Place soil fill on subgrades free of mud, frost, snow, or ice. <br />3.14 SOIL MOISTURE CONTROL <br />A. Uniformly moisten or aerate subgrade and each subsequent fill or backfill soil layer before <br />compaction to within 3 percent of optimum moisture content. <br />1. Do not place backfill or fill soil material on surfaces that are muddy, frozen, or contain <br />frost or ice. <br />2. Remove and replace, or scarify and air dry, otherwise satisfactory soil material that exceeds <br />optimum moisture content by 3 percent and is too wet to compact to specified dry unit <br />weight. <br />3.15 COMPACTION OF SOIL BACKFILLS AND FILLS <br />A. Place backfill and fill soil materials in layers not more than 8 to 10 in loose depth for material <br />compacted by heavy compaction equipment and not more than 4 inchesin loose depth for material <br />compacted by hand-operated tampers. <br />B. Place backfill and fill soil materials evenly on all sides of structures to required elevations and <br />uniformly along the full length of each structure. <br />C. Compact soil materials to not less than the following percentages of maximum dry unit weight <br />according to ASTM D 698: <br />1. Under structures, building slabs, steps, and pavements, scarify and recompact top 12 <br />inchesof existing subgrade and each layer of backfill or fill soil material at 98 percent. <br />2. Under walkways, scarify and recompact top 6 inchesbelow subgrade and compact each <br />layer of backfill or fill soil material at 95 percent. <br />3. Under turf or unpaved areas, scarify and recompact top 6 inchesbelow subgrade and <br />compact each layer of backfill or fill soil material at 85 percent. <br />4. For utility trenches, compact each layer of initial and final backfill soil material at 98 <br />percent and in turf areas 85 percent. <br />DocuSign Envelope ID: 7D9ACD4F-8F6C-42B6-9ADB-C60032DB6D03