News Releases - 2001

Chicago Area Achieves Health Smog Standard Early

Chicago -- Illinois Environmental Protection Agency Director Renee Cipriano today announced air monitoring data for the past three years shows the Chicago area is the largest metropolitan area in the nation to achieve the one-hour health standard for ground-level ozone (smog) — six years ahead of the federal deadline.

Illinois EPA Director Renee Cipriano (left) checks ozone levels with environmental "superhero" Breathe Easy Man (right) at the "Renewable City" exhibit at the Chicago Museum of Science and Industry.

Illinois plans to petition the U.S. Environmental Protection Agency for formal redesignation of the area to "attainment" under the federal Clean Air Act, Director Cipriano said. "If approved by USEPA, that will mean Chicago will also be the largest city in the nation to go from a designation of severe non-attainment to attainment," she added.

The severe non-attainment designation was given in response to the 1990 Clean Air Act Amendments because of numerous ozone monitor readings the prior three years in excess of the federal health standard of 125 parts per billion, called "exceedances." U.S. EPA originally set the standard in 1978. The monitors measure the average concentration of ozone in the air over a one-hour period.

Included in the original designation were the Illinois counties of Cook, DuPage, Lake, Kane, McHenry, Will and portions of Kendall and Grundy, as well as Lake and Porter Counties in Indiana and Kenosha and Racine Counties in Wisconsin.

To qualify for attainment, none of the individual monitoring sites can measure more than three exceedances within three years.

None of the 21 ozone monitors located in the Illinois portion of the Chicago non-attainment area recorded any exceedances of the one-hour ozone standard during the past three years. This year's ozone season in Illinois ended Oct. 31.

Illinois has vigorously implemented a variety of regulatory and voluntary programs impacting both industrial sources and vehicles to reduce the primary chemicals — volatile organic compounds, and nitrogen oxides — that react with sunlight to form ground-level ozone. As a result, there have been substantial reductions in the amounts of those chemicals going into the air.

Current U.S. EPA regulations require states to meet the attainment standard by November 2007. Illinois' petition will demonstrate that it has met the standard six years ahead of the federal requirement.

"This is a great milestone that has been achieved because of the efforts of business and individual citizens, and government, to reduce the pollutants that can cause ozone,"said Governor George H. Ryan.

"We must remember our work is not done," said Director Cipriano. "Together, we face more challenges ahead in maintaining our compliance with the one-hour standard and addressing the new eight-hour standard for ozone."

U.S. EPA has not yet issued regulations or a timetable to implement the eight-hour health standard for ozone, which would set a limit of 85 parts per billion, averaged over an eight-hour period.