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 |
40 C.F.R. §52.171