National Academy
of Sciences Meets to Discuss Ethanol's Impact on Ozone
The first meeting of the National Academy of Sciences Committee
charged with reviewing scientific data regarding ethanol's impact on urban
ozone formation was held in October. The Environmental Protection Agency
asked for the Academy review following a request from Senator Dick Lugar.
As currently structured, the EPA's mass-volatile organic compounds based
regulations for the reformulated gasoline program make it difficult to
use ethanol, particularly in Phase II reformulated gasoline. The increased
oxygen content and reduced reactivity of ethanol's emissions, however,
can more than offset the impact of increased mass-volatile organic compounds.
Dennis Lawler with the Illinois EPA presented the results of the Council
of Great Lakes Governors' Urban Airshed Model conducted for Chicago in
1993, which found that there is no difference in ozone formation with the
use of either 10 percent ethanol or 11 percent MTBE in reformulated gasoline.
Gary Whitten of Systems Applications, Inc. discussed the impact of carbon
monoxide and nitrogen oxide emissions on ozone, as well as the effect of
exhaust emissions on reactivity, the effect of commingling, distillation
and enrichment, and the relevance of urban airshed models.
Other presenters included Dean Simeroth, Air Director of the California
Air Resources Board regarding California's low emission vehicle program
and ongoing ethanol reactivity study, and Cal Hodge of the Oxygenated Fuels
Association, who spoke to the importance of utilizing reactivity to assess
the air quality benefits of clean fuels.
