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Green Book

1-Hour Ozone (1979) Nonattainment Area Summary - NAAQS Revoked

As of September 22, 2016
Classification Number of Areas Number of Counties 2010 Population
Extreme 2 12 17,784,954
Severe 17 6 51 35,418,992
Severe 15 6 48 16,736,177
Serious 8 38 16,125,782
Moderate 5 12 1,736,909
Marginal 16 38 7,367,934
Rural Transport (Marginal) 2 2 0
Other 1 9 6,541,828
 
SUBTOTAL 46 201 101,712,576
 
Section 185A 3 4 459,668
Incomplete Data 14 15 1,259,464
 
SUBTOTAL 17 19 1,719,132
 
GRAND TOTAL 63 219 103,431,708

County subtotals and grand totals may not equal sum of parts.

Part counties are only counted one time within groupings.

"Section 185A" was previously called "Transitional".

The former 1-hour ozone designations and classifications as of June 15, 2004, are being retained in subpart C of Part 81 for purposes of the anti backsliding provisions of 40 CFR 51.905. 40 CFR 51.905(c) references subpart C of part 81 for the areas affected by the anti-backsliding regulation.


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