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Code · CFR · Title 40 — Protection of Environment · Part 52 · § 52.121

§ 52.121. Classification of regions.

74 words·~1 min read·/us/cfr/t40/s§ 52.121·

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The Arizona plan is evaluated on the basis of the following classifications: AQCR (constituent counties) Classifications PM SOX NO2 CO O3 Maricopa Intrastate (Maricopa)IIIIIIIII Pima Intrastate (Pima)IIIIIIIIIIIII Northern Arizona Intrastate (Apache, Coconino, Navajo, Yavapai)IIIIIIIIIIIII Mohave-Yuma Intrastate (La Paz, Mohave, Yuma)IIIIIIIIIIIII Central Arizona Intrastate (Gila, Pinal)IIAIIIIIII Southeast Arizona Intrastate (Cochise, Graham, Greenlee, Santa Cruz)IIAIIIIIIIII [83 FR 42219, Aug. 21, 2018, as amended at 89 FR 71835, Sept. 4, 2024; 90 FR 59056, Dec. 18, 2025]
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§ 52.121
Classification of regions.
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