40 CFR § 81.158
Southern Wisconsin Intrastate Air Quality Control Region
June 9, 2020
The Southern Wisconsin Intrastate Air Quality Control Region consists of the territorial area encompassed by the boundaries of the following jurisdictions or described area (including the territorial area of all municipalities (as defined in section 302(f) of the Clean Air Act, 42 U.S.C. 1857h(f)) geographically located within the outermost boundaries of the area so delimited):
In the State of Wisconsin: Columbia County, Dane County, Dodge County, Green County, Iowa County, Jefferson County, Lafayette County, Richland County, Sauk County.