Abandoned underground oil tanks are a potential source of soil and groundwater contamination. Underground oil tanks should be decommissioned whenever they are no longer used, if they have questionable structural integrity, or if they are leaking.

According to the Model Toxics Control Act, a tank owner may be held liable for contamination caused by a leak.

Often the abandoned tank does not become an issue until the homeowner decides to sell their home. The inspections done before closing exposes the abandoned tank, resulting in the lending institutions and homebuyers requiring sellers to remove or decommission the abandoned heating oil tank.