UST systems in use on or after December 22, 1998 must meet the closure requirements at 40 CFR 280.70 when an owner and operator decides to close the UST system. You can close your UST temporarily or permanently. In either case, USTs must be closed properly.
Closing TemporarilyYou may temporarily close your UST for up to 12 months by following these requirements for temporary closure:
- Continue to monitor for leaks by maintaining the UST's leak detection. (If your UST is empty, you do not need to maintain leak detection. An UST is considered empty if no more than one inch of residue is present or not more than 0.3 percent by weight of the total capacity of the UST system remains in the system.) Also, continue to monitor and maintain any corrosion protection systems. If a release is discovered, quickly stop the release, notify your regulatory authority, and take appropriate action to clean up the site.
- If the UST remains temporarily closed for more than 3 months, leave vent lines open, but cap and secure all other lines, pumps, manways, and ancillary equipment.
- You must permanently close your UST if it doesn't meet the applicable requirements for new or upgraded USTs (except for spill and overfill).
- You can ask your regulatory authority for an extension beyond 12 months, if you provide an assessment that determines whether contamination is present at your site.
- Your UST can remain temporarily closed without needing an extension granted by the regulatory authority if the UST meets the applicable requirements for new or upgraded USTs (except for spill and overfill) and the requirements noted above for temporary closure.
Closing PermanentlyIf you decide to close your UST permanently, follow these requirements for permanent closure:
- Notify the regulatory authority at least 30 days before you close your UST.
- Determine if contamination from your UST is present in the surrounding environment. If there is contamination, you may have to take corrective action. For at least 3 years, keep a record of the actions you take to determine if contamination is present at the site (or you can mail this record to your regulatory authority).
- Either remove the UST from the ground or leave it in the ground. In both cases, the tank must be emptied and cleaned by removing all liquids, dangerous vapor levels, and accumulated sludge. These potentially very hazardous actions need to be carried out carefully by trained professionals who follow standard safety practices. If you leave the UST in the ground, have it filled with a harmless, chemically inactive solid, like sand.
Don't forget to check with your state agency for their closure requirements.
Safe Closure Is A Must
People who do not follow standard safety practices are killed or injured every year while closing or removing tanks. For a safe closure, you need qualified professionals who will use standard safety practices.
For more information on standard safety practices, UST owners and closure contractors should refer to "Closure of Underground Petroleum Storage Tanks," API Recommended Practice 1604 (1996), which is available from the American Petroleum Institute, 1220 L Street, NW, Washington, DC 20005, or call (202) 682-8000 for assistance. You can also visit API's website.
The video and companion booklet called "Tank Closure Without Tears: An Inspector's Safety Guide" are available from the New England Interstate Environmental Training Center at (978) 323-7929. You can also visit NEIWPCC's website.