Backfall

Refers to a length of pipe having an upward gradient opposite to the direction of flow.

Backfill Density

Percent compaction for pipe backfill (required or expected).

Backflow Device

Mechanism that prevents wastewater from flowing back upstream.

Backstop

Reinforced area of the entrance pit wall directly behind the track.

Band

A ring of steel welded at or near the front of the lead section of casing to cut relief and strengthen the casing.