1507.025   BACKFILLING.
   (a)   Unless otherwise specified, backfill shall consist of coarse interlocking aggregate, including back-run gravel or limestone screenings. All fill shall be free of objectionable material and must be satisfactory to the City Engineer. No slag or foundry sand may be used.
   (b)   Where pipe is laid in a trench, all backfill shall be carefully placed and compacted by using an approved tamper. No wood blocking is to be left under pipes.
   (c)   The contractor must exercise care in placing backfill to a point eighteen inches above the pipe and must make certain that it is compacted properly in order that the pipe is not moved or that the alignment of the pipe is not disturbed. All trenches shall be backfilled in eighteen-inch maximum layers and tamped after each layer.
   (d)   All trenches, whether located in tree lawns or yards, shall be filled and compacted to within twelve inches of the finished grade. All trenches located under concrete or asphalt driveways, sidewalks or slag-type foundations shall be filled and compacted to finish grade with premium-type fill.
   (e)   Filling of all types of trenches relating to sewers and/or water valve boxes, abandoned lines or slab foundations shall be of premium fill and compacted to eliminate any and all settlement.
   (f)   All porches or decks which require concrete slabs shall be free of objectionable material and shall be of premium fill compacted to finish grade to eliminate any and all settlement.
(Ord. 20-92. Passed 2-18-92.)