1020.06   BACKFILL METHODS.
   The method of making the necessary backfill where an excavation has been made shall be as follows:
   (A)   If a sewer is to be covered, stone sand shall be tamped solidly under and around the sewer, with proper tools for that purpose, to a depth of twelve inches. The remainder of the backfill shall be deposited in layers not exceeding four inches in thickness, each of which layers shall be well pounded and rammed with a rammer of suitable weight or with an approved pneumatic tamper.
   (B)   In the case of an excavation other than a sewer, the earth backfill shall be compacted in four-inch layers the same as stone backfill and shall at all times be compacted to a density of not less than ninety percent of the maximum density, according to the provisions of the State of Ohio Department of Transportation Construction and Material Specifications, the latest edition. Care that the backfill material contains the proper amount of moisture so as to obtain the maximum compaction shall be exercised at all times.
   (C)   In lieu of subsections (A) and (B) hereof, ready-mixed "flowable fill" may be used. If "flowable fill" is used, then overcutting the trench, as shown in the Standard Drawings is not necessary. The fill shall be placed to within two inches of the existing surface. The mix shall be: 100 pounds of Portland concrete cement, 300 pounds of (Class C) fly ash, 2,600 pounds of fine aggregate and approximately seventy gallons of water. The mix will yield approximately ICY of flowable mortar with a compressive strength of approximately 100 psi.
   Additional details of backfill methods can be found in the City of Lima's Standard Drawings available in the office of the City Engineer.
(Ord. 5-86. Passed 1-6-86.)