In underground storage tank installation projects, compaction refers to the process of tamping or packing backfill material. Compaction helps prevent subsequent settling of the material. If voids are allowed to remain in the backfill, the tanks will not have adequate support.
Mechanical compactors are sometimes used. These are machines, about the size of power lawn mowers that employ a vibrating motion to pack sand or other backfill material into tighter compression.
