The U.S. Environmental Protection Agency counts more than 700,000 underground storage tanks still in operation nationwide, 30% of which may be leaking. Because the EPA database recognizes only registered tanks, the actual UST population is probably many times higher than the EPA estimate.

This much is certain: All USTs will eventually require permanent closure. And closure must include testing for past leaks and spills, an often-overlooked step.

Assessing the Site at UST Closure

According to Subpart 280.72 of the federal UST regulations, "Before permanent closure or a change-in-service is completed, owners and operators must measure for the presence of a release where contamination is most likely to be present at the UST site." Click Here for More

This requirement applies whether you plan to remove the tank or abandon it in place, and regardless of its age, size or condition. Previously abandoned tanks are not exempt from the site assessment requirement (Subpart 280.73). Closure and assessment records must be maintained for at least 3 years (Subpart 280.74). If soil or groundwater are found to be contaminated, the tank owner or operator must begin corrective action.

Guidance for UST Closure Site Assessments in New York

State and local protocols vary from agency to agency when it comes to assessing the "presence of a release."

In New York State, UST regulations are spelled out in the Code of Rules & Regulations (6NYCRR Parts 612-614) Acceptable procedures for UST closure assessment and remediation, however, must be gleaned from an alphabet soup of guidance documents known as SPOTS, TAGMs and STARS:

• Spill Prevention Operations Technology Series (SPOTS) #14: Site Assessments at Bulk Storage Facilities provides guidance on procedures and measurements to determine if past leaks or spills have caused soil or groundwater contamination: Field observations; sample collection, screening and analysis; contaminant delineation; reporting; and record keeping. See also, API Publication #1628: A Guide to the Assessment and Remediation of Underground Petroleum Releases, available HERE

• Technical and Administrative Guidance Memorandum (TAGM) #4046: Determination of Soil Cleanup Objectives and Cleanup Levels sets forth procedures to determine soil cleanup levels for site remediation. Downloadable HERE


• Spill Technology and Remediation Series (STARS) Memorandum #1: Petroleum-Contaminated Soil Guidance Policy sets forth requirements for handling, testing, disposal and/or reuse of non-hazardous petroleum-contaminated soil. Downloadable by clicking HERE.


• See also a series of 2000 and 2001 memos clarifying TAGM #4046 and STARS Memo #1, which can be downloaded HERE.

Photo: Glass vial containing water and PCB oil globules collected by Conrad Geoscience from a residential well.