TO INSURE PROPER COMPACTION AROUND PIPING, TRENCHES SHALL BE BACKFILLED WITH CLEAN EARTH IN THIN LAYERS TO AT LEAST______INCHES ABOVE THE TOP OF THE PIPE THEREAFTER DEEPER LAYERS ARE PERMITTED.

TO INSURE PROPER COMPACTION AROUND PIPING, TRENCHES SHALL BE BACKFILLED WITH CLEAN EARTH IN THIN LAYERS TO AT LEAST______INCHES ABOVE THE TOP OF THE PIPE THEREAFTER DEEPER LAYERS ARE PERMITTED.