Underground Oil Tank Removal

Tanks still leaking.

Residential underground oil storage tanks (USTs) commonly begin leaking after about 20 to 30 years of use. Most residential underground oil tanks are now over 50 years old and have been leaking for many years, even while still in service. Often a significant quantity of heating oil remains in these tanks, even after many years of leaking.

What must be done.

Most residential heating oil tanks are not regulated by the State of NC, but leakage from a tank and/or soil contamination must be reported to the NC Department of Environmental Quality (NCDEQ). Before the property may be legally conveyed, a Notice of Residual Petroleum must be filed for the property. This Notice must be filed before the NCDEQ will issue a Notice of No Further Action (NFA) for the release. Obtaining a NFA is commonly a minimum requirement for banks and buyers before a property is sold.

Underground tank located between the aboveground tank that replaced it and a water supply well.

UST fill and vent pipes are visible in front of the replacement AST. This is an almost certain sign that the UST has leaked. A water supply well is next to the underground tank. The State will require further work in this case, or the well must be abandoned.

High risk situations.

Underground oil tank removal, cleanup of contaminated soils, and environmental assessment work is usually not required for residential sites. However, certain site conditions are considered as emergency or high risk factors by the NCDEQ.

Two such risk factors commonly encountered are:

  • The presence of a water supply wells, whether in use or not, within 150 feet of a leaking heating oil tank.
  • The presence of oil or oil vapors in the crawlspace or basement areas of a residence.

In these cases soil cleanup work or other environmental assessment, which could include the removal of the tank and excavation of contaminated soils, will be required.

Additionally, prospective buyers, or financial institutions, or insurers, may require the removal of an oil tank, whether it has leaked or not.

Underground tank beneath new foundation trench.

UST exposed under new foundation trench. This required removal of the UST as it would not have the strength to support the extension foundation.

Site inspections essential.

During a site inspection, Cedar Rock assesses any site conditions that may cause the State to require tank removal and/or other environmental cleanup and assessment work, and will provide advice and recommendations for your situation. Cedar Rock normally recommends proper abandonment of an underground tank which ensures that the tank will not cause any new problems, or worsen existing issues. Tank removal disturbs the landscape much more than tank abandonment.

Severely corroded underground oil tank being removed from the ground.

Severely corroded 1,000-gallon UST being removed from beside a house.

Tank removal procedure.

Underground oil tank removal typically involves access to the UST location with a backhoe. The tank is exposed and then cut open to allow removal of fluids and cleaning of the tank. If required, contaminated soils are excavated and transported to a disposal facility. An average size excavation pit is about a 10 foot cube. The pit is backfilled and tamped to grade, and the impacted yard is regraded, reseeded, and strawed. This process requires about one day to complete.

What to do next.

Your first step should be to organize a site inspection to determine if your property of interest has any USTs, and whether or not they have leaked. Cedar Rock can inspect the property and locate any USTs, and determine whether or not they have leaked. Cedar Rock will then be able to advise you on the possible courses of action and the factors to be considered in deciding what to do about the UST(s). Cedar Rock is able to provide services to abandon or remove USTs and to satisfy requirements of the NCDEQ before a NFA is issued.

Schedule a site inspection today to check for the presence of an underground oil tank and/or soil contamination on your property of interest. Call us at 336 684-2734 or use our online contact form.