The subgrade shall be free of sod, vegetative, or organic matter, soft clay, and other objectionable materials for a depth of at least two feet below the finished surface of the subgrade. The subgrade shall be properly rolled, shaped, and compacted and shall be subject to the approval of the Village Engineer. Soils tests shall be performed by a soils testing laboratory. Copies of the tests shall be furnished to the Village Engineer. Costs of the tests are the responsibility of the subdivider.