40 CFR 52.171: Classification of regions.

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

Air quality control region Pollutant

Particulate matter Sulfur oxides Nitrogen dioxide Carbon monoxide Ozone

Central Arkansas Intrastate II III III III III

Metropolitan Fort Smith Interstate II III III III III

Metropolitan Memphis Interstate I III III III I

Monroe (Louisiana)-El Dorado (Arkansas) Interstate II III III III III

Northeast Arkansas Intrastate III III III III III

Northwest Arkansas Intrastate III III III III III

Shreveport-Texarkana-Tyler Interstate II III III III III