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Underground Storage Tanks (USTs)

The National LUST Cleanup Backlog: A Study of Opportunities

(EPA 510-R-11-003). September 2011.

As of September 2020, over 559,000 releases from federally-regulated leaking underground storage tanks (LUSTs) were confirmed nationwide since the beginning of the UST program. States and EPA in Indian country have cleaned up over 493,000 of the releases. However, approximately 62,000 UST releases remain to be cleaned up (also known as the backlog). Reducing the backlog remains a priority for the national UST program, and states and EPA are continuing their steady progress on this effort. EPA’s semiannual report of UST performance measures provides information such as newly-confirmed UST releases reported and cleanups completed, both of which affect the number of UST releases in the backlog.

To understand the characteristics of UST releases in the backlog and why the pace of cleanup is slowing, EPA undertook a two-phase, data-driven analysis of LUST cleanups as of 2006 (Phase 1) and 2009 (Phase 2). The Phase 2 study, The National LUST Cleanup Backlog: A Study of Opportunities, compiled and analyzed available data from 14 state LUST programs. It identified key findings and potential opportunities to support continued reduction of the LUST cleanup backlog. 

As a result of this study, EPA is working with states, tribes, and other stakeholders to promote targeted cleanup strategies that can assist in bringing more releases to closure.  The national chapter discusses many of the strategies that states and EPA are already using, including:  

For more information on EPA’s backlog study, contact:

Susan Burnell (202) 564-0766
State and Territorial UST/LUST Program Contacts

The report contains a national chapter, 14 individual state chapters, and two appendices.

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