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

As of September 22, 2016
Classification Number of Areas Number of Counties 2010 Population
Severe 15 1 13 3,698,679
Serious 5 12 8,836,372
Moderate 24 83 28,003,515
Marginal 23 48 14,121,934
Rural Transport (Marginal) 2 2 39,605
Other 1 5 1,521,635
SUBTOTAL 56 163 56,221,740
Section 185A 8 17 5,007,208
Incomplete Data 9 11 921,272
SUBTOTAL 17 28 5,928,480
GRAND TOTAL 73 191 62,150,220

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

Part counties are only counted one time within groupings, and only if the county is not in a nonattainment area for the pollutant. So Kern Co is not counted, since it is in the East Kern Co maintenance area and in the San Joaquin Valley nonattainment area.

The Ohio portion of the Youngstown-Warren-Sharon OH-PA area is a maintenance area, while the Pennsylvania portion remains nonattainment. This report does not count the partially redesignated areas.

"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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