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8-Hour Ozone (2015) Nonattainment Area Summary

Data is current as of September 30, 2021


Classification Number of Areas Number of Counties 2010 Population
Extreme 2 12 19,544,668
Severe 15 3 1 4,369,276
Serious 2 1 821,740
Moderate 4 31 22,634,693
Marginal 38 157 77,352,596
Marginal (Rural Transport) 2 2 17,004
SUBTOTAL 51 204 124,739,977
 
GRAND TOTAL 51 204 124,739,977

County subtotals and grand totals may not equal sum of parts. Part counties are only counted one time across groupings. Multi-state nonattainment areas are not considered maintenance areas until all states in the area have been redesignated