WASHINGTON — States no longer will have to add corn-based ethanol or MTBE to gasoline to fight pollution -- a requirement that costs as much as 8 cents a gallon -- under rules announced Wednesday by the Environmental Protection Agency.
The rules eliminate a mandate from the 1990 Clean Air Act that gasoline used in the smoggiest metropolitan areas contain 2% oxygen by weight. That law did not say which oxygenate must be used, but most refiners use either ethanol or methyl tertiary-butyl ether, known as MTBE.
California, New York and Connecticut unsuccessfully had asked the EPA for a waiver of the requirement because the states had banned MTBE after finding it polluted the groundwater. The states were forced to use ethanol, which they contended had worsened pollution problems.
In denying the waiver request, most recently in June, the EPA said the states had not shown that using an oxygenate had prevented or interfered with their ability to meet federal air standards.
The rules announced Wednesday fulfill part of the energy law enacted last summer.
Sen. Dianne Feinstein (D-Calif.) said: "The announcement means that California refiners will finally be allowed to make gasoline that is cleaner-burning than what they are making today."
The rules will take effect nationwide May 6 and in California 60 days after their publication in the Federal Register, which should happen within the next three months, said EPA spokesman John Millett. (California has a different status under clean-air laws than the rest of the country because of the state's pollution problems.)
Parts of more than a dozen states have been under the 2% oxygenate requirement, according to the EPA; others use oxygenates voluntarily. Nationwide, about 30% of gasoline contains oxygenates.
Oxygenate additives on average increase the price of gasoline by 4 cents to 8 cents a gallon, the EPA estimates.
But the agency says the benefits include at least 100,000 tons per year fewer smog pollutants nationally, equivalent to the tailpipe emissions of 16 million vehicles.
Refineries now have other ways to blend cleaner-burning fuel that will allow states to achieve clean-air benefits without using oxygenates, the EPA says, though states still can use oxygenates if they choose.