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Title 40

Displaying title 40, up to date as of 9/23/2021. Title 40 was last amended 9/23/2021.

Title 40

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§ 52.121 Classification of regions.

The Arizona plan is evaluated on the basis of the following classifications:

AQCR (constituent counties) Classifications
PM SOX NO2 CO O3
Maricopa Intrastate (Maricopa) I III III I I
Pima Intrastate (Pima) I III III III I
Northern Arizona Intrastate (Apache, Coconino, Navajo, Yavapai) I III III III III
Mohave-Yuma Intrastate (Mohave, Yuma) I III III III III
Central Arizona Intrastate (Gila, Pinal) I IA III III III
Southeast Arizona Intrastate (Cochise, Graham, Greenlee, Santa Cruz) I IA III III III

[83 FR 42219, Aug. 21, 2018]