Buried Oil Tanks: Hidden Hazards for Homeowners and Buyers

When purchasing an older home, one of the most significant hidden liabilities can be an underground storage tank (UST), commonly known as a buried oil tank. These tanks, once a standard method for storing heating oil, pose severe environmental and financial risks if they begin to leak.

The Risks of a Leaking Tank

Most buried oil tanks are made of bare steel, which inevitably corrodes over time. When a tank leaks, heating oil can contaminate the surrounding soil and groundwater. The cost of environmental cleanup is substantial and typically falls on the current property owner, regardless of who owned the home when the leak occurred.

Signs of a Buried Oil Tank

While the tank itself is underground, there are often clues to its existence. Look for fill pipes or vent pipes protruding from the ground near the foundation, or disconnected oil lines in the basement. However, some tanks have been abandoned with no visible surface evidence.

The Importance of a Tank Sweep

A tank sweep, or underground storage tank search, uses specialized equipment like ground-penetrating radar or metal detectors to locate buried tanks. This search is a critical step during the due diligence period of a home purchase, especially for homes built before the 1990s.

What to Do if a Tank is Found

If a tank is discovered, it must be properly addressed. This usually involves removing the tank and testing the soil for contamination. In some cases, a tank can be legally abandoned in place by filling it with an inert material like sand or foam, but removal is generally preferred to eliminate future liability.