UNUSED UNDERGROUND RESIDENTIAL HEATING OIL TANKS

Unused underground residential heating oil tanks ("UURHOT's") are increasingly becoming a matter of environmental concern. There are thousands of UURHOT's in Washington, many of which still contain heating oil. They are typically 200-300 gallons in size and are constructed of bare 12-gauge steel (about 1/8 thick). After 20 to 30 years in the ground, corrosion makes them prone to leakage and collapse.

Presently, there are no regulations specifically covering UURHOT's, other than the fire code requirement that a UURHOT taken out of service longer than one year must be removed or closed in a manner approved by the local fire department. However, lenders are increasingly requiring UURHOT's to be removed or closed as a condition of making a loan.

The Department of Ecology ("DOE") recommends the following actions for UURHOT owners:

1. Determine whether any heating oil remains in the tank.
2. Remove any remaining heating oil from the tank. Removing the oil ensures against future leakage and contamination, for which the owner could be liable. Oil recycling companies (Listed in the yellow pages under "Oil--Waste") will usually pump the tank for les than $100.
3. Clean and inert the inside of the tank. After removing the remaining oil, there will likely be a sludge left on the bottom of tank from foreign matter that has gotten into the tank and matter that has settled out of the heating oil. Companies that pump the tanks will often clean and inert them (remove the vapors) for an additional fee of about $400.
4. Unearth and remove the tank. The DOE recommends removal of UURHOT's as the most complete solution to the problem. The cost for removing and disposing of an UURHOT varies widely depending on location and accessibility, but is usually between $1,000 and $4,000.Once the tank is removed, any soil contamination from leaking or spilling must also be cleaned up. Again, professional assistance is highly recommended.
5. Fill the tank in place with an inert solid material. A less expensive alternative to removing an UURHOT, the tank could be pumped, cleaned, and filled with an inert solid material (typically sand, gravel, or concrete). The purpose of filling UURHOT's with inert material is to prevent the tank from shifting, floating, or collapsing, and to prevent harmful vapors from accumulating. The primary disadvantages of filing the tank are the increased costs of future removal and the potential for unknown soil contamination, which cause many lenders to require removal, rather than filling. Unless the UURHOT is either removed or closed in a manner approved by the local fire department, and any soil contamination is cleaned up, the existence of the UURHOT on the property should be disclosed to the purchaser. Of course, a real estate agent is not an expert on UURHOT's, and interested parties should contact the DOE, local fire department, and qualified professionals for additional information and assistance.

This article contains general information only, and should not be used or relied upon as a substitute for competent legal advice in specific situations.

RE LAW Bulletin No. 016 Page 1 of 1 Revised 4/1/92

Courtesy of:

Dougas S. Tingvall
Attorney at Law