The Arkansas plan was evaluated on the basis of the following classifications: ----------------------------------------------------------------------------------------------------------------
Pollutant
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Air quality control region Particulate Sulfur Nitrogen Carbon
matter oxides dioxide monoxide Ozone----------------------------------------------------------------------------------------------------------------Central Arkansas Intrastate............................... II III III III IIIMetropolitan Fort Smith Interstate........................ II III III III IIIMetropolitan Memphis Interstate........................... I III III III IMonroe (Louisiana)-El Dorado (Arkansas) Interstate........ II III III III IIINortheast Arkansas Intrastate............................. III III III III IIINorthwest Arkansas Intrastate............................. III III III III IIIShreveport-Texarkana-Tyler Interstate..................... II III III III III---------------------------------------------------------------------------------------------------------------- [37 FR 10850, May 31, 1972, as amended at 39 FR 16346, May 8, 1974; 45 FR 6571, Jan. 29, 1980]