40 CFR § 81.220
Eastern Oregon Intrastate Air Quality Control Region
June 9, 2020
The Eastern Oregon 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 Oregon: Baker County, Gilliam County, Grant County, Harney County, Malheur County, Morrow County, Umatilla County, Union County, Wallowa County, Wheeler County.