The Maine plan was evaluated on the basis of the following classifications:
Air quality control region | Pollutant | ||||
Particulate matter | Sulfur oxides | Nitrogen dioxide | Carbon monoxide | Ozone | |
Metropolitan Portland Intrastate | I | II | III | III | III |
Androscoggin Valley Interstate | IA | IA | III | III | III |
Down East Intrastate | IA | IA | III | III | III |
Aroostook Intrastate | III | III | III | III | III |
Northwest Maine Intrastate | III | III | III | III | III |
40 C.F.R. §52.1021