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8-Hour Ozone (2015) Nonattainment Area Summary
8-Hour Ozone (2015) Nonattainment Area Summary
Data is current as of March 31, 2025Classification | Number of Areas | Number of Counties | 2010 Population |
---|---|---|---|
Extreme | 2 | 12 | 19,544,668 |
Severe 15 | 3 | 1 | 4,369,276 |
Serious | 23 | 124 | 72,123,048 |
Moderate | 6 | 26 | 10,208,117 |
Marginal | 11 | 18 | 8,920,691 |
Marginal (Rural Transport) | 1 | 1 | 0 |
SUBTOTAL | 46 | 182 | 115,165,800 |
GRAND TOTAL | 46 | 182 | 115,165,800 |
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