Adjustments to Original 8-Hour Ozone (2015) Nonattainment Area Baseline

Data is current as of September 30, 2024

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BOUNDARY CHANGE

June 14, 2021, Effective July 14, 2021 ( 86 FR 31438 )

Chicago, IL-IN-WI - ILLINOIS

June 14, 2021, Effective July 14, 2021 ( 86 FR 31438 )

Chicago, IL-IN-WI - INDIANA

June 14, 2021, Effective July 14, 2021 ( 86 FR 31438 )

Chicago, IL-IN-WI - WISCONSIN

June 14, 2021, Effective July 14, 2021 ( 86 FR 31438 )

Manitowoc County, WI - WISCONSIN

June 14, 2021, Effective July 14, 2021 ( 86 FR 31438 )

Milwaukee, WI - WISCONSIN

June 14, 2021, Effective July 14, 2021 ( 86 FR 31438 )

Sheboygan County, WI - WISCONSIN

June 14, 2021, Effective July 14, 2021 ( 86 FR 31438 )

St. Louis, MO-IL - ILLINOIS

June 14, 2021, Effective July 14, 2021 ( 86 FR 31438 )

St. Louis, MO-IL - MISSOURI

November 30, 2021, Effective December 30, 2021 ( 86 FR 67864 )

Denver Metro/North Front Range, CO - COLORADO

November 30, 2021, Effective December 30, 2021 ( 86 FR 67864 )

El Paso-Las Cruces, TX-NM - TEXAS

CHANGE TO A HIGHER CLASSIFICATION (BUMP-UPS)

June 02, 2021, Effective July 02, 2021 ( 86 FR 29522 )

San Diego County, CA - CALIFORNIA

Reclassify from Moderate to Severe 15

DESIGNATION TO NONATTAINMENT

July 25, 2018, Effective September 24, 2018 ( 83 FR 35136 )

San Antonio, TX - TEXAS

June 14, 2021, Effective July 14, 2021 ( 86 FR 31438 )

Door County-Revised, WI - WISCONSIN