The South Dakota plan evaluated on the basis of the following classifications: ----------------------------------------------------------------------------------------------------------------
Pollutant
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Air quality control region Photochemical
Particulate Sulfur Nitrogen Carbon oxidants
matter oxides dioxide monoxide (hydrocarbons)----------------------------------------------------------------------------------------------------------------Metropolitan Sioux City Interstate................... III III III III IIIMetropolitan Sioux Falls Interstate.................. II III III III IIIBlack Hills--Rapid City Intrastate................... III III III III IIISouth Dakota Intrastate.............................. III III III III III---------------------------------------------------------------------------------------------------------------- [37 FR 10893, May 31, 1972]