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8-Hour Ozone (2015) Nonattainment Area Summary

Data is current as of August 31, 2020


Classification Number of Areas Number of Counties 2010 Population
Extreme 2 12 19,544,668
Severe 15 2 3 1,291,989
Serious 2 2 821,740
Moderate 5 33 25,711,980
Marginal 38 154 75,048,694
Marginal (Rural Transport) 1 1 0
SUBTOTAL 50 196 122,419,071
 
GRAND TOTAL 50 196 122,419,071

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