Adjustments to Original 8-Hour Ozone (1997) Nonattainment Area Baseline

Data is current as of December 31, 2019


The 1997 8-hour Ozone NAAQS was revoked effective April 6, 2015 (80 FR 12264). Thirteen (13) EAC areas were designated attainment on April 15, 2008. Details can be seen here.

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Effective October 15, 2019, the initial designation of the SO2 (2010) Williamson County, IL nonattainment area was changed from nonattainment to attainment/unclassifiable (84 FR 48286).

AREA SPLIT

September 23, 2013, Effective October 23, 2013 ( 78 FR 58189 )

Los Angeles-South Coast Air Basin, CA - CALIFORNIA

September 23, 2013, Effective October 23, 2013 ( 78 FR 58189 )

Morongo Band of Mission Indians - CALIFORNIA

April 03, 2015, Effective April 03, 2015 ( 80 FR 18120 )

Pechanga Band of Luiseno Mission Indians of the Pechanga Reservation - CALIFORNIA

July 15, 2019, Effective July 15, 2019 ( 84 FR 33699 )

Inland Sheboygan County, WI - WISCONSIN

July 15, 2019, Effective July 15, 2019 ( 84 FR 33699 )

Shoreline Sheboygan County, WI - WISCONSIN

BOUNDARY CHANGE

September 17, 2004, Effective September 13, 2004 ( 69 FR 55956 )

Las Vegas, NV - NEVADA

The revised designation defines a smaller nonattainment area around the City of Las Vegas and designates the remainder of Clark County with the rest of the State as ``unclassifiable/attainment.''

October 13, 2006, Effective October 13, 2006 ( 71 FR 60429 )

Macon, GA - GEORGIA

This action corrects the 8-hour ozone nonattainment boundary for Monroe County, Georgia by deleting a highway from the boundary description, and clarifies the 8-hour ozone nonattainment boundary for Murray County, Georgia by adding a boundary description.

April 03, 2015, Effective April 03, 2015 ( 80 FR 18120 )

Los Angeles-South Coast Air Basin, CA - CALIFORNIA

April 03, 2015, Effective April 03, 2015 ( 80 FR 18120 )

San Diego, CA - CALIFORNIA

CHANGE TO A LOWER CLASSIFICATION

September 22, 2004, Effective November 22, 2004 ( 69 FR 56697 )

Cass Co, MI - MICHIGAN

Reclassify from Moderate to Marginal

September 22, 2004, Effective November 22, 2004 ( 69 FR 56697 )

Detroit-Ann Arbor, MI - MICHIGAN

Reclassify from Moderate to Marginal

September 22, 2004, Effective November 22, 2004 ( 69 FR 56697 )

Kent and Queen Anne's Cos, MD - MARYLAND

Reclassify from Moderate to Marginal

September 22, 2004, Effective November 22, 2004 ( 69 FR 56697 )

La Porte Co., IN - INDIANA

Reclassify from Moderate to Marginal

September 22, 2004, Effective November 22, 2004 ( 69 FR 56697 )

Lancaster, PA - PENNSYLVANIA

Reclassify from Moderate to Marginal

September 22, 2004, Effective November 22, 2004 ( 69 FR 56697 )

Memphis, TN-AR - ARKANSAS

Reclassify from Moderate to Marginal

September 22, 2004, Effective November 22, 2004 ( 69 FR 56697 )

Memphis, TN-AR - TENNESSEE

Reclassify from Moderate to Marginal

September 22, 2004, Effective November 22, 2004 ( 69 FR 56697 )

Muskegon, MI - MICHIGAN

Reclassify from Moderate to Marginal

September 22, 2004, Effective November 22, 2004 ( 69 FR 56697 )

Richmond-Petersburg, VA - VIRGINIA

Reclassify from Moderate to Marginal

CHANGE FROM SUBPART 1 TO SUBPART 2

May 14, 2012, Effective June 13, 2012 ( 77 FR 28424 )

Albany-Schenectady-Troy, NY - NEW YORK

Change from Former Subpart 1 to Marginal

May 14, 2012, Effective June 13, 2012 ( 77 FR 28424 )

Amador and Calaveras Cos. (Central Mountain Cos.), CA - CALIFORNIA

Change from Former Subpart 1 to Moderate

May 14, 2012, Effective June 13, 2012 ( 77 FR 28424 )

Buffalo-Niagara Falls, NY - NEW YORK

Change from Former Subpart 1 to Moderate

May 14, 2012, Effective June 13, 2012 ( 77 FR 28424 )

Chico, CA - CALIFORNIA

Change from Former Subpart 1 to Marginal

May 14, 2012, Effective June 13, 2012 ( 77 FR 28424 )

Denver-Boulder-Greeley-Ft. Collins-Loveland, CO - COLORADO

Change from Former Subpart 1 to Marginal

May 14, 2012, Effective June 13, 2012 ( 77 FR 28424 )

Essex Co (Whiteface Mtn), NY - NEW YORK

Change from Former Subpart 1 to Marginal

May 14, 2012, Effective June 13, 2012 ( 77 FR 28424 )

Jamestown, NY - NEW YORK

Change from Former Subpart 1 to Moderate

May 14, 2012, Effective June 13, 2012 ( 77 FR 28424 )

Kern Co (Eastern Kern), CA - CALIFORNIA

Change from Former Subpart 1 to Moderate

May 14, 2012, Effective June 13, 2012 ( 77 FR 28424 )

Las Vegas, NV - NEVADA

Change from Former Subpart 1 to Marginal

May 14, 2012, Effective June 13, 2012 ( 77 FR 28424 )

Mariposa and Tuolumne Cos (Southern Mtn), CA - CALIFORNIA

Change from Former Subpart 1 to Moderate

May 14, 2012, Effective June 13, 2012 ( 77 FR 28424 )

Nevada Co. (Western part), CA - CALIFORNIA

Change from Former Subpart 1 to Moderate

May 14, 2012, Effective June 13, 2012 ( 77 FR 28424 )

Phoenix-Mesa, AZ - ARIZONA

Change from Former Subpart 1 to Marginal

May 14, 2012, Effective June 13, 2012 ( 77 FR 28424 )

Pittsburgh-Beaver Valley, PA - PENNSYLVANIA

Change from Former Subpart 1 to Moderate

May 14, 2012, Effective June 13, 2012 ( 77 FR 28424 )

Rochester, NY - NEW YORK

Change from Former Subpart 1 to Marginal

May 14, 2012, Effective June 13, 2012 ( 77 FR 28424 )

San Diego, CA - CALIFORNIA

Change from Former Subpart 1 to Moderate

May 14, 2012, Effective June 13, 2012 ( 77 FR 28424 )

Sutter Co (Sutter Buttes), CA - CALIFORNIA

Change from Former Subpart 1 to Marginal

CHANGE TO A HIGHER CLASSIFICATION (BUMP-UPS)

February 13, 2008, Effective March 14, 2008 ( 73 FR 8209 )

Imperial Co, CA - CALIFORNIA

Reclassify from Marginal to Moderate

March 06, 2008, Effective April 07, 2008 ( 73 FR 12013 )

Atlanta, GA - GEORGIA

Reclassify from Marginal to Moderate

March 18, 2008, Effective April 17, 2008 ( 73 FR 14391 )

Beaumont-Port Arthur, TX - TEXAS

Reclassify from Marginal to Moderate

March 21, 2008, Effective April 21, 2008 ( 73 FR 15087 )

Baton Rouge, LA - LOUISIANA

Reclassify from Marginal to Moderate

March 28, 2008, Effective April 28, 2008 ( 73 FR 16547 )

Memphis, TN-AR - ARKANSAS

Reclassify from Marginal to Moderate

March 28, 2008, Effective April 28, 2008 ( 73 FR 16547 )

Memphis, TN-AR - TENNESSEE

Reclassify from Marginal to Moderate

May 20, 2008, Effective June 19, 2008 ( 73 FR 29073 )

Ventura Co, CA - CALIFORNIA

Reclassify from Moderate to Serious

October 01, 2008, Effective October 31, 2008 ( 73 FR 56983 )

Houston-Galveston-Brazoria, TX - TEXAS

Reclassify from Moderate to Severe-15

May 05, 2010, Effective June 04, 2010 ( 75 FR 24409 )

Los Angeles-South Coast Air Basin, CA - CALIFORNIA

Reclassify from Severe-17 to Extreme

May 05, 2010, Effective June 04, 2010 ( 75 FR 24409 )

Riverside Co. (Coachella Valley), CA - CALIFORNIA

Reclassify from Serious to Severe-15

May 05, 2010, Effective June 04, 2010 ( 75 FR 24409 )

Sacramento Metro, CA - CALIFORNIA

Reclassify from Serious to Severe-15

May 05, 2010, Effective June 04, 2010 ( 75 FR 24409 )

San Joaquin Valley, CA - CALIFORNIA

Reclassify from Serious to Extreme

December 20, 2010, Effective January 19, 2011 ( 75 FR 79302 )

Dallas-Fort Worth, TX - TEXAS

Reclassify from Moderate to Serious

February 01, 2012, Effective March 02, 2012 ( 77 FR 4901 )

Baltimore, MD - MARYLAND

Reclassify from Moderate to Serious

May 08, 2012, Effective June 07, 2012 ( 77 FR 26950 )

Los Angeles-San Bernardino Cos. (W Mojave Desert), CA - CALIFORNIA

Reclassify from Moderate to Severe-15

July 10, 2019, Effective July 10, 2019 ( 84 FR 32841 )

Riverside Co. (Coachella Valley), CA - CALIFORNIA

Reclassify from Severe 15 to Extreme

DESIGNATION TO NONATTAINMENT

April 02, 2008, Effective April 15, 2008 ( 73 FR 17897 )

Denver-Boulder-Greeley-Ft. Collins-Loveland, CO - COLORADO