The Metropolitan Billings Intrastate Air Quality Control Region (Montana) has been renamed the Billings Intrastate Air Quality Control Region and 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):
Code of Federal Regulations
Note:
For purposes of identification, the Regions are referred to by Montana authorities as follows:
Sec.
481.168Great Falls Intrastate Air Quality Control Region: Region II.
481.169Helena Intrastate Air Quality Control Region: Region IV.
481.170Miles City Intrastate Air Quality Control Region: Region III.
481.171Missoula Intrastate Air Quality Control Region: Region I.
481.88Billings Intrastate Air Quality Control Region: Region V.