40 CFR § 52.721 - Classification of regions.

§ 52.721 Classification of regions.

The Illinois plan was evaluated on the basis of the following classifications:

Air quality control region Pollutant
Particulate matter Sulfur oxides Nitrogen dioxide Carbon monoxide Ozone
Burlington-Keokuk Interstate I I III III III
East Central Illinois Intrastate III II III III III
Metropolitan Chicago Interstate (Indiana-Illinois) I I I I I
Metropolitan Dubuque Interstate I III III III III
Metropolitan Quad Cities Interstate I III III III III
Metropolitan St. Louis Interstate (Missouri-Illinois) I I III I I
North Central Illinois Intrastate II IA III III III
Paducah (Kentucky)-Cairo (Illinois) Interstate I II III III III
Rockford (Illinois)-Janesville-Beloit (Wisconsin) Interstate II III III III III
Southeast Illinois Intrastate III II III III III
West Central Illinois Intrastate I IA III III III
[37 FR 10862, May 31, 1972, as amended at 39 FR 16346, May 8, 1974; 45 FR 11493, Feb. 21, 1980]

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