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Environmental Protection: MTBE Contamination From Underground Storage Tanks

GAO-02-753T Published: May 21, 2002. Publicly Released: May 21, 2002.
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To help limit air pollution, about a third of the states use gasoline that contains methyl tertiary butyl ether (MTBE), which burns cleaner. However, MTBE has migrated into wells and groundwater from leaking underground tanks used to store gasoline. The Environmental Protection Agency (EPA) has the responsibility through the Underground Storage Tank Program and works through the states to ensure that tanks do not leak and, if they do, that the contamination is cleaned up. To help states cover the program costs, Congress annually provides grants from a trust fund it created in 1986. Most of the 50 states have reported finding MTBE when they discover gasoline contamination in their tank sites and increasingly, in their groundwater, surface water, and drinking water. States have made progress in addressing the releases they have discovered, including MTBE contamination, but face a continuing and substantial cleanup workload. States typically depend on tank owners or operators to pay some of the cleanup costs and cover the remainder with their own funding programs and depend on relatively small federal trust fund grants to pay staff to oversee cleanups and administer their programs.

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ContaminationEnvironmental monitoringstate relationsHazardous substancesHealth hazardsPollution controlSafety standardsState-administered programsTanks (containers)Water pollutionWater pollution controlEnvironmental protection