Closing Regulated Underground Storage Tanks

(If your underground storage tank installed before November 30, 1987, and is regulated by the Department of Agriculture and Natural Resources (DANR), you will have to close or upgrade your underground storage tank to meet the December 22,1998, compliance deadline.


Tank Closure

Closure is one way to help protect human health and the environment, particularly groundwater, from the threats posed by many older underground storage tanks. Was your underground storage tank (UST) installed before November 30 1987, and is it regulated by the Department of Agriculture and Natural Resources (DANR) ? If the answer is "yes," by December 22, 1998, you must select one of the following three options: Upgrade the UST by adding spill, overfill, and corrosion protection, OR Replace it with a new UST that has spill, overfill, and corrosion protection, OR Properly close the old UST. The information that follows will help you close your UST properly. You can close your UST temporarily or permanently.


Closing Temporarily

You may temporarily close your UST for up to 12 months by following these requirements: 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.) Also, continue to monitor and maintain any corrosion protection systems. If a release is discovered, quickly stop the release, notify DANR, 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. After 12 months of temporary closure, you have two options: 1. UST systems that meet the current compliance requirements and have had all product removed from them, may be left in temporary closure provided an assessment has been done to show no leakage has occurred from the tank system and the results from the leak detection system show no loss of product. 2. USTs may be left in place longer than 12 months provided certain specific site conditions are met. Please contact Storage Tank Section to discuss the conditions.


Closing Permanently

If you decide to close your UST permanently, follow these requirements: Notify the Department of Agriculture and Natural Resources at least 30 days before you close your UST. Perform a site assessment to determine if the tank has leaked. The simplest form of a site assessment is to collect soil samples under each tank (in the case of removal) or as close to the tank basin (in the case of in-place closure), and also from beneath the dispenser. A soil sample must also be taken from under the distribution line, if it is more than 25 feet long. These samples must be sent to a laboratory to be analyzed for the presence of contamination. For all analyses of soil and groundwater for petroleum-hydrocarbon contamination, the person collecting the samples must be certified by the State of South Dakota. The test results must be sent to the DANR. If the test results show samples are free from contamination, you will receive a tank closure letter from DANR. If there is contamination, you may have to take corrective action. A program was developed by the South Dakota Legislature to provide funds for clean up of contamination caused by the release from petroleum underground storage tanks. The program is administered by the Petroleum Release Compensation Fund (PRCF). For specific information on fund deductibles and certification requirements, please contact the PRCF at Phone (605) 773-3769.


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 call the Department of Agriculture and Natural Resources (DANR), Phone # (605) 773-3296. UST Owners and Closure Contractors should refer to South Dakota's "Handbook For Investigation and Corrective Action Requirements For Discharges from Storage Tanks, Piping Systems and Other Releases" Version 2.0, March 2003. This guidance has been developed by the Department of Agriculture and Natural Resources, Inspection, Compliance, & Remediation Program.


Hire a Qualified Contractor

The following tips may help you find a reliable contractor to close your tanks: Ask other tank owners who have closed tanks to recommend contractors they have used. Look closely at the contractor's qualifications and experience to make sure you are satisfied with both. Ask for references from the contractor.


Want More Information?

If you have any further questions concerning the storage tank program, please contact Kayla Fawcett, Justin Allen, Marshall Brown, or Bailey McTigue in Pierre at (605) 773-3296, or Scott Bickler in Sioux Falls at (605) 362-3500 or in Rapid City contact Zachary Burggraff at (605) 394-2229 or E-mail

Risk to Public and Private Wells

The South Dakota Department of Environment and Natural Resources has developed a comprehensive guidance document on how to evaluate risk to public and private wells from a petroleum release site. The guidance document also clarifies the Tier 2 risk based assessment and Tier 3 requirements at the aquifer sites including the wellhead protection areas.

The Tier 3 modeling can be done at release sites where Tier 2 risk based assessment has been done and identified the presence of public or private wells. For details check out the guidance document.