Regulations last checked for updates: Nov 24, 2024

Title 40 - Protection of Environment last revised: Nov 21, 2024
§ 52.1221 - Classification of regions.

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

Air quality control region Pollutant
Particulate matter Sulfur oxides Nitrogen dioxide Carbon monoxide Photochemical oxidants (hydrocarbons)
Central Minnesota IntrastateIIIIIIIIIIIIII
Southeast Minnesota-La Crosse (Wisconsin) InterstateIIIaIIIIIIIII
Duluth (Minnesota)-Superior (Wisconsin) InterstateIIIIIIIIIIII
Metropolitan Fargo-Moorhead InterstateIIIIIIIIIIIIII
Minneapolis-St. Paul IntrastateIIIIIIIII
Northwest Minnesota IntrastateIIIIIIIIIIIIII
Southwest Minnesota IntrastateIIIIIIIIIIIIIII
[37 FR 10874, May 31, 1972, as amended at 39 FR 16346, May 8, 1974]
authority: 42 U.S.C. 7401
cite as: 40 CFR 52.1221