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Underground Storage Tanks (USTs)

Significant Operational Compliance (SOC) Performance Measures

States will continue to report on SOC until they implement their revised 2015 UST regulations.  States who have already implemented the 2015 regulations will report on the Technical Compliance Rate measures.

In 2003 EPA and its state partners developed a uniform method for measuring certain aspects of underground storage tank (UST) system operational compliance with release detection and prevention requirements. Below are links to documents which discuss the background of the significant operational compliance effort; reporting requirements; criteria for determining significant operational compliance; matrices; and related matters. Significant Operational Compliance data from 2002 to present can be found in the UST Performance Measures.

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