40 CFR 52.2221: Classification of regions.

The Tennessee 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)

Eastern Tennessee-Southwestern Virginia Interstate I I III III III

Tennessee River Valley-Cumberland Mountains Intrastate I I III III III

Middle Tennessee Intrastate I II III III I

Western Tennessee Intrastate I III III III III

Chattanooga Interstate I II III III III

Metropolitan Memphis Interstate I III III III I