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Environment DEC


From the March 2008 issue

MTBE Study of LI Gas Stations Released

Four years after the gasoline additive methyl tertiary butyl ether (MTBE) was banned from New York State, the effects of the chemical continue to pose environmental and public health threats to Long Island's aquifer, according to a new study released by the Department of Environmental Conservation (DEC). The study of 52 retail gasoline stations in Nassau and Suffolk counties concentrated on two known MTBE issues--spills and groundwater contamination.

gas pump
MTBE is now banned, but concerns remain about the additive's effect on human health and the environment

Testing uncovered 32 petroleum spills that were not previously reported. These spills affected soil and/or groundwater, with one spill in Ronkonkoma threatening a public drinking water supply. DEC's actions at the site prevented the drinking water from becoming contaminated.

Potentially Widespread Contamination

New York was among the first states in the country to ban MTBE as a gasoline additive, and, as of 2004, it is no longer legally allowed as a component of gasoline sold in the state. Despite that, the recent study confirmed that MTBE contamination from spills continues to pose risks to the Long Island aquifer system, the sole source of drinking water for more than 2.7 million residents in Nassau and Suffolk counties.

Because of MTBE's ability to migrate with groundwater flow beyond an individual site's boundaries, the potential for contamination is more widespread than at specific locations such as gas stations. With approximately 1,100 gasoline stations on Long Island alone, the findings of this study represent the overall effect MTBE may be having on the region, as well as in other communities throughout New York.

Risks Outweigh Benefits

MTBE is a manufactured chemical compound that had been used in New York and other states since 1979 as an oxygenate additive to gasoline to help reduce air pollution. Despite the perceived air-quality benefits, DEC grew concerned about effects on groundwater from spills of gasoline containing MTBE and, in 1998, determined there was a need to further assess the effects and extent of MTBE contamination. A subsequent survey of gasoline spills reported between July 1978 and September 1998 showed that 32 percent had MTBE effects on groundwater quality, predominantly on Long Island.