In July 15, 2015, EPA published the 2015 underground storage tank regulation and the 2015 state program approval regulation. The revisions strengthen the 1988 federal underground storage tank (UST) regulations by increasing emphasis on properly operating and maintaining UST equipment. The revisions will help prevent and detect UST releases, which are a leading source of groundwater contamination. The revisions will also help ensure all USTs in the United States, including those in Indian country, meet the same minimum standards. This is the first major revision to the federal UST regulations since 1988.