Appeals Court Upholds California MTBE Ban

Published August 1, 2003

A federal appeals court has upheld California’s ban on the controversial gasoline additive MTBE (methyl tertiary butyl ether), finding the ban does not violate the federal Clean Air Act.

The Clean Air Act mandates that oxygenated agents be blended with gasoline to reduce pollution from vehicle exhaust systems. MTBE long has been the most prevalent agent blended with gasoline to satisfy the mandate, and the Natural Resources Defense Council has been particularly adamant in its championing of MTBE.

However, recent studies have suggested MTBE is contaminating groundwater and may cause cancer in humans at high enough levels.

Although the links between MTBE and human health concerns are largely speculative, in April of this year a California jury held Shell Oil and two other energy companies liable for MTBE that made its way into Lake Tahoe. Twenty-eight other defendants in the case had earlier settled out of court for $33 million in damages.

Free-market environmentalists have not missed the opportunity to point out such groundwater pollution would not have occurred if the federal government had not mandated costly and only marginally effective gasoline additives in the first place.

According to Ben Lieberman, director of clean air policy for the Competitive Enterprise Institute, “Given the downward trends in motor vehicle emissions, and expected continued declines as older cars and trucks are continually replaced by newer, cleaner ones, it is arguable that there was no need for the federal government to regulate fuel content. Nonetheless, the 1990 amendments to the Clean Air Act established detailed requirements for gasoline.

“Fortunately, the MTBE battle has broadened into a larger debate over whether oxygenates are needed at all,” added Lieberman. “The best response to MTBE concerns is to entirely eliminate the oxygen content requirement” from the Clean Air Act.

The panel of the federal Ninth Circuit Court of Appeals in San Francisco rejected arguments that the California MTBE ban unlawfully circumvented the federal Clean Air Act. The court determined the ban was proper because its environmental purpose “does not conflict with the goals and purposes of the Clean Air Act.”

The appellate court decision is just one of many recent blows to MTBE. After an economic boom after the Clean Air Act of 1990 virtually mandated the widespread use of MTBE, more than a dozen states have taken steps to ban the additive.

Moreover, the U.S. House and Senate each have passed bills this summer that would double the mandatory use of ethanol, a rival to MTBE. The Senate version would ban MTBE completely. A House-Senate conference committee will determine whether the MTBE ban will be incorporated into the final compromise bill.

James M. Taylor is managing editor of Environment & Climate News. His email address is [email protected].

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