The U.S. Environmental Protection Agency is finalizing a rule designed to recognize the additional carbon monoxide benefits provided by reformulated gasoline blended with 10 percent ethanol. The rule will provide a volatile organic compounds credit equal to 0.3 pounds per square inch Reid vapor pressure, providing refiners additional flexibility in meeting the volatile organic compounds standard in ethanol-blended reformulated gasoline.

The ruling implements the recommendation of the National Research Council that the reformulated gasoline program recognize the contribution of carbon monoxide to smog formation. The ruling will maintain the air quality benefits of reformulated gasoline while reducing the need for refiners to use specially tailored, low-Rvp blendstocks with ethanol, and thus potentially reducing the cost to produce ethanol-blended reformulated gasoline.

Currently the adjustment is limited to Chicago and Milwaukee. As ethanol reduces carbon monoxide emissions wherever it is used, the ethanol industry supports expanding the rule to cover the other reformulated gasoline areas already using ethanol-blended fuel: St. Louis, Missouri; Louisville, Kentucky; Cincinnati, Ohio; and California. Approximately 50 percent of St. Louis, Louisville and Cincinnati reformulated gasoline is blended with ethanol, while 10 percent of California reformulated gasoline contains ethanol.