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Benzene Contamination

Environmental pollution by benzene, a carcinogenic compound found in gasoline and commonly detected at LUST sites.

Benzene is a volatile organic compound (VOC) and known human carcinogen that is a natural component of crude oil and gasoline. It is one of the most commonly detected contaminants at leaking underground storage tank sites. Benzene is highly mobile in groundwater and poses serious health risks even at very low concentrations, making it a primary driver of cleanup requirements at LUST sites.

The EPA's Maximum Contaminant Level (MCL) for benzene in drinking water is 5 parts per billion (ppb), reflecting its carcinogenic potential. At LUST sites, benzene concentrations in groundwater can range from trace levels to thousands of ppb near the source area. Benzene can also volatilize from contaminated groundwater and soil, creating vapor intrusion risks for nearby buildings.

Remediation of benzene contamination often involves a combination of technologies including groundwater extraction and treatment, air sparging, soil vapor extraction, and enhanced bioremediation. Natural attenuation of benzene occurs through biodegradation, but the process may be too slow to protect sensitive receptors. Sites with benzene contamination near drinking water sources typically receive priority attention from regulatory agencies.

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