The U.S. Environmental Protection Agency is seeking comment on its proposal to credit the additional carbon monoxide benefits of ethanol-blended fuels under the reformulated gasoline program. The Agency proposes to reduce the Phase 2 reformulated gasoline volatile organic compounds performance standard by 1 percentage point for reformulated gasoline blends with 10 percent ethanol (3.5 wt. percent), approximately equivalent to an Reid vapor pressure increase of 0.2 psi). The adjustment is expected to provide refiners with additional flexibility in producing blendstocks for reformulated gasoline with ethanol.

The Environmental Protection Agency is also seeking comment on a proposal by the Illinois Environmental Protection Agency that supports a volatile organic compounds adjustment of 3.7 percentage points (equivalent to an increase in Reid vapor pressure of 0.5 psi) for carbon monoxide emissions reductions from the use of ethanol reformulated gasoline. In fact, the analysis demonstrates that an even greater Reid vapor pressure credit for ethanol may be appropriate when considering a base fuel with no oxygenates rather than one blended with MTBE.