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§ 52.821 Classification of regions.

40 CFR 52.821

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Citation40 CFR 52.821
CorpusDaily eCFR
Displayed edition2026-05-14
Last updated2026-05-14

§ 52.821 Classification of regions.

The Iowa plan was evaluated on the basis of the following classification:

Air quality control regionPollutant
Particulate matterSulfur oxidesNitrogen dioxideCarbon monoxidePhotochemical oxidants (hydrocarbons)
Metropolitan Omaha-Council Bluffs InterstateIIIIIIIIIIII
Metropolitan Sioux Falls InterstateIIIIIIIIIIIIII
Metropolitan Sioux City InterstateIIIIIIIIIIIIIII
Metropolitan Dubuque InterstateIIIIIIIIIIIII
Metropolitan Quad Cities InterstateIIIIIIIIIIIII
Burlington-Keokuk InterstateIIIIIIIIIII
Northwest Iowa IntrastateIIIIIIIIIIIIIII
North Central Iowa IntrastateIAIIIIIIIIIIII
Northeast Iowa IntrastateIIIIIIIIIIIII
Southwest Iowa IntrastateIIIIIIIIIIIIIII
South Central Iowa IntrastateIIIIIIIIIII
Southeast Iowa IntrastateIIIIIIIIIIIIIII

[37 FR 10865, May 31, 1972, as amended at 39 FR 16346, May 8, 1974]