In light of new data suggesting carbon monoxide is a major contributor to ozone pollution, U.S. Environmental Protection Agency Assistant Administrator for Air and Radiation Bob Perciasepe said the EPA is pursuing a carbon monoxide standard for reformulated gasoline. To assist EPA with this effort, the Illinois EPA recently provided the Agency with a detailed analysis demonstrating the carbon monoxide benefits of a 10 percent ethanol blend.
"Consistent with this analysis, we believe that USEPA should allow a credit of at least 0.5 pounds per square inch Reid vapor pressure for the use of 10 percent volume blends of ethanol," Illinois EPA Bureau of Air Chief Bharat Mathur wrote to EPA. "In fact, the analysis suggests even a greater Reid vapor pressure credit for ethanol may be appropriate when considering a base fuel with no oxygenate, rather than MTBE. We believe that levels of 0.2 pounds per square inch, as has been suggested by some, does not provide full credit for the benefits resulting from the use of 3.5 weight percent oxygen blends." Mathur noted that an equivalent amount of ozone pollution results from a 7.3 pounds per square inch Reid vapor pressure reformulated gasoline fuel with 3.5 weight percent ethanol as from a 6.8 pounds per square inch Reid vapor pressure reformulated gasoline fuel with the minimum 2.0 weight percent oxygen.
