Residential heating oil tanks are not regulated.
Home heating oil tanks under 1,100 gallons are not regulated.

Residential underground storage tanks (USTs) require a closure permit for decommissioning.
In some instances, an inspection is also required.

Residential above ground tanks (ASTs) do not require permits.

Certain permitting agencies will allow homeowners to decommission tanks in place by leaving them empty once they have been pumped, triple rinsed and permanently capped.
Other agencies require homeowners to fill their tank or have them removed completely.

We do not use of polyurethane spray foam (PSF) to fill tanks.

• In its application phase, PSF releases harmful vapors
  known to make humans and animals sick.

• Until reaching a fully cured state, PSF emits harmful
  green house gasses. PSF is a petroleum based product.

• PSF does not provide consistently sound structural
  integrity for abandoned tanks.

• PSF makes tanks buoyant, rendering them virtual
  buoys. Tanks filled with PSF can actually surface under
  the right conditions.

• PSF has not been proven in the tank industry. Many
  states and municipalities prohibit the use of PSF for
  use in filling abandoned tanks.

Underground storage tanks are not always the cause of soil contamination.
Heating oil fuel lines associated with underground storage tanks can be a source of soil contamination if they are not properly installed or become damaged.