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§ 52.321 Classification of regions.

40 CFR 52.321

Citation40 CFR 52.321
CorpusDaily eCFR
Displayed edition2026-05-14
Last updated2026-05-14

§ 52.321 Classification of regions.

The revised Denver Emergency Episode Plan, adopted by the State of Colorado February 28, 1996, was submitted by the Governor of Colorado with a September 16, 1997 letter.

Air quality control regionPollutant
Particulate matterSulfur oxidesNitrogen dioxideCarbon monoxideOzone
Pawnee IntrastateIIIIIIIIIIIII
Metropolitan Denver IntrastateIIIIIIIII
Comanche IntrastateIIIIIIIIIIIIIII
San Isabel IntrastateIIIIIIIIIIIII
San Luis IntrastateIIIIIIIIIIIIIII
Four Corners InterstateIAIAIIIIIIIII
Grand Mesa IntrastateIIIIIIIIIIIIIII
Yampa IntrastateIIIIIIIIIIIIIII

[37 FR 10855, May 31, 1972, as amended at 39 FR 16346, May 8, 1974; 44 FR 57409, Oct. 5, 1979; 74 FR 47891, Sept. 18, 2009]