Classification of regions.

The New York plans were evaluated on the basis of the following classifications: Air quality control region Pollutant Particulate matter Sulfur oxides Nitrogen dioxide Carbon monoxide Photochemical oxidants (hydrocarbons) Niagara Frontier Intrastate I I III III I Champlain Valley Interstate II II III III III Central New York Intrastate I II III I I Genesee-Finger Lakes Intrastate II II III III I Hudson Valley Intrastate I II III III III Southern Tier East Intrastate II II III III III Southern Tier West Intrastate II II III III III New Jersey-New York-Connecticut Interstate I I I I I [37 FR 10882, May 31, 1972, as amended at 39 FR 16347, May 8, 1974]