The Wyoming plan was evaluated on the basis of the following classifications:
| Air quality control region
| Pollutant
|
|---|
| Particulate matter
| Sulfur oxides
| Nitrogen dioxide
| Carbon monoxide
| Photochemical oxidants (hydrocarbons)
|
|---|
| Cheyenne Intrastate | II | III | III | III | III
|
| Casper Intrastate | II | III | III | III | III
|
| Wyoming Intrastate | III | III | III | III | III |