(A) Earthwork shall consist of preparing the subgrade, backfilling along the curbs, shaping the soil in accordance with the engineer’s instruction and approved construction plans, providing borrow and disposing of waste material.
(B) Excavation shall be true to the depths, slopes, grade and width as called for on the plans or as otherwise staked and ordered by the engineer. The work shall be so conducted that the excavation shall drain. No material that would be classified as rock or stone which could not be passed through a three-inch circular ring shall be left within 12 inches of the top of the finished subgrade. Care shall be exercised that no material be loosened below the required grade line. If soft, spongy materials which will not compact readily and form an unyielding roadbed are encountered below the grade, the contractor shall remove them, under the direction of the engineer, and replace them with IDOT gradation 13 crushed stone, or other material acceptable to the engineer, and compact as herein specified.