Groundwater Contamination
The pollution of underground water sources by petroleum products or hazardous substances from leaking USTs or other sources.
Groundwater contamination from leaking underground storage tanks is one of the most widespread environmental problems in the United States. When petroleum products or hazardous substances leak from UST systems, they can migrate through soil and reach the water table, contaminating aquifers that serve as drinking water sources for millions of Americans.
Petroleum-related groundwater contamination typically involves compounds like benzene, toluene, ethylbenzene, and xylenes (collectively known as BTEX), as well as fuel additives like MTBE. These contaminants can travel significant distances in groundwater plumes, affecting water supplies far from the original release location.
The EPA tracks proximity to drinking water sources for all UST facilities and LUST release sites. Key metrics include the population within 1,500 feet, the number of private wells nearby, and whether the site is within a source water protection area or wellhead protection area. Sites with greater proximity to drinking water sources typically receive higher priority for investigation and cleanup.
Related Terms
A designated zone around a public water supply well where contamination poses a direct threat to drinking water quality.
Source Water Protection Area (SPA)The area from which a public water system draws its drinking water, where contamination prevention is critical.
Benzene ContaminationEnvironmental pollution by benzene, a carcinogenic compound found in gasoline and commonly detected at LUST sites.
MTBE ContaminationEnvironmental pollution by methyl tert-butyl ether (MTBE), a gasoline additive that readily dissolves in and contaminates groundwater.