Cavity Excavation

To create Cavity Excavation, fill in required cover on diagram below – allow for pavement and fill. ACO recommends a minimum of 12" total cover for landscape applications and a minimum of 24" for vehicle traffic applications.

Cover Material
Cover material is split between pavement and fill. Fill cover dimension on diagram below.

Cover Layer in
Base Layer 6 in

Backfill Material
Backfill material will be calculated from a 6" layer under the tank with 24" at all sides. Cover dimension filled in the diagram above will be used in the calculation. Please note, this does not account for your pavement design. The finished floor surface (bitumen, concrete, etc.) dimension will need to be removed by you from the Backfill Material calculation given here.

Backfill Material 100 ft3
100 ft
100 ft
100 ft

Diagram shows cavity size rounded to nearest foot.

See Excavation Plan