Jump to main content.

8-Hour Ozone Nonattainment Areas
(1997 Standard)

This page provides detailed information on designations and classifications of 8-hour ozone nonattainment areas.

On June 8, 2007, the United States Court of Appeals vacated the Subpart 1 portion of the Phase 1 Rule (Court Order). The Subpart 1 areas in the Greenbook are listed as "Former Subpart 1" until the reclassification of the areas is finalized. Proposed reclassifications were published on January 16, 2009 (74 FR 2936).

  1. Nonattainment Area Selections
    1. Area Listings
      1. Areas by Category/Classification
      2. Sorted by State/Area/County
      3. Sorted by Area/State/County
    2. Area Designation Data
      1. Air Quality Data, Population, Counties

  2. Maintenance Area Selections (Previously Nonattainment Areas)
    1. Area Listings
      1. Classified Areas Sorted by Classification
      2. Sorted by State/Area/County
      3. Sorted by Area/State/County
    2. Area Designation Data
      1. Air Quality Data, Population, Counties

  3. Area Maps
    1. National Maps
      1. National 8-Hour Ozone County Map of Maintenance and Nonattainment Areas in the U.S.
      2. National Map of 8-Hour Ozone Nonattainment Areas
    2. State Maps
      1. Individual State Maps with 8-Hour Nonattainment Areas
      2. Individual State Maps with 8-Hour Maintenance Areas
    3. State Map PDF Downloads
      1. File of All Maintenance State Maps in PDF format (.zip)
      2. File of All Nonattainment State Maps in PDF format (.zip)
    4. Area Shapefile Downloads
      1. GIS Area Download Page

  4. Other Information
    1. Summary Reports
      1. Nonattainment Area Summary Report
      2. Maintenance Area Summary Report
      3. Nonattainment Area Summary Report w/ History
    2. Comparison to Other Standards
      1. 8-Hour and Previous 1-Hour Ozone State/County Detail Report
      2. Sorted by State/Area/County with CO, PM-10, PM-2.5 and Previous 1-hr Ozone Classifications
      3. Sorted by Area/State/County with CO, PM-10, PM-2.5 and Previous 1-hr Ozone Classifications
      4. 8-Hr Ozone Nonattainment and Maintenance Areas and Previous 1-Hr Ozone Areas
      5. 8-Hr Ozone Nonattainment and Maintenance Areas Compared to 2006 PM-2.5 and 1997 PM-2.5 Nonattainment Areas
    3. 8-Hour Ozone Unclassifiable Areas
      1. Kansas and Missouri 8-Hour Ozone Unclassifiable Area Redesignation Federal Register Notices
        2. [ Proposal (February 10, 2005) ]   [ Final (May 3, 2005) ]
      2. Syracuse NY 8-Hour Ozone Unclassifiable Area Redesignation Federal Register Notices
        3. [ Proposal (July 7, 2005) ]   [ Final (May 15, 2006) ]

  5. Early Action Compact Areas (Attainment - Previously Deferred Designation)

    6. Based on air quality data from 2005, 2006 and the first three quarters of 2007, the Denver CO
    Subpart 1 EAC area was designated nonattainment for 8-hour Ozone, effective November 20, 2007
    (72 FR 53952).

    On February 6, 2008, EPA proposed (73 FR 6863) and on April 2, 2008, finalized (73 FR 17897)
    the designation of the remaining 13 Early Action Compact (EAC) Areas as attainment
    for the 8-hour ozone National Ambient Air Quality Standard (NAAQS), effective April 15, 2008.

    1. Area Listings
      1. Areas Sorted by Classification
      2. Sorted by State/Area/County
      3. Sorted by Area/State/County
    2. Area Maps
      1. U.S. Map
    3. Area Designation Data
      1. Air Quality Data, Population, Counties
    4. Summary Report
      1. EAC Summary
    5. Federal Register Notices
      1. Relating to EAC Areas

  6. Areas with a Maintenance Plan Requirement Under Section 110(a)(1) of the CAA

    The phase 1 final rule to implement the 8-hour ozone standard was published on April 30, 2004. The anti backsliding provisions in that rule set forth specific requirements for areas that are designated attainment for the 8-hour ozone standard; and that were - at the time of the 8-hour designations (generally June 15, 2004) - either attainment areas with maintenance plans for the 1-hour standard; or nonattainment for the 1-hour standard.

    Specifically, 40 CFR part 51, section 51.905(a)(3) and (4) requires these areas to submit a maintenance plan under section 110(a)(1) of the CAA. That maintenance plan must demonstrate maintenance out to 10 years after designation. This maintenance plan does not, however, carry with it any conformity obligations (unlike maintenance plans required under section 175A of the Act. The section 110(a)(1) maintenance plan must be submitted within 3 years after designation for the 8-hour ozone standard.

    1. Area Listings
      1. Classified Areas Sorted by Classification
      2. Sec. 185A Areas (for Sec 185A definition, click here.)
      3. Incomplete or No Data Areas
      4. Sorted by State/Area/County
      5. Sorted by Area/State/County
    2. Area Maps
      1. Classification by County - U.S. Map
    3. Area Designation Data
      1. Classified
      2. Sec. 185A
      3. Incomplete or No Data
    4. Area Summary Report
    5. Federal Register Notices
      1. 110(a)(1) Maintenance Plans

    The Maintenance Areas (Previously Nonattainment Areas) which are still subject to the 1-hour standard have maintenance plans required under section 175A, but are not at this time subject to the Section 110(a)(1) maintenance plan provision under 40 CFR part 51, section 51.905(a)(3) and (4). When the 1-hour standard no longer applies, they will be required to submit 110(a)(1) maintenance plans under 40 CFR part 51, section 51.905(a)(3) and (4), if they are attainment for the 8-hour standard.

    The areas are: Nashville, TN, Greensboro Winston Salem High Point, NC, and Denver Boulder, CO.


  7. Links to Related Topics
    1. More information on 8-hour ozone designations
    2. Early Action Compacts

  8. Federal Register Notices Relating to 8-Hour Ozone Designations and Classifications
    for the 1997 Standard
    1. Designation Notices
      1. 8-Hour Ozone Designation Federal Register Notice (April 30, 2004)     [ HTML ]   [ PDF ]
      2. 8-Hour Ozone Designation Federal Register Notice (June 18, 2004): Amends April 30, 2004 Notice     [ HTML ]
      3. Phase 2: Final 8-Hour Ozone Implementation Federal Register Notice (November 29, 2005)     [ HTML ]   [ PDF ]
      4. DC Court of Appeals Ozone Implementation Ruling (December 22, 2006)     [ PDF ]
      5. Phase 2 of the Final Rule To Implement the 8-Hour Ozone National Ambient Air Quality Standard--Notice of Reconsideration (June 8, 2007)     [ HTML ]
      6. DC Court of Appeals Ozone Implementation Rehearing (June 8, 2007)     [ PDF ]
      7. Proposed Settlement Agreement: Denver EAC Designation to Nonattainment, Effective November 20, 2007 (October 1, 2007)     [ HTML ]
      8. Ozone (O3) Standards - Documents from Review Completed in 2008 - Federal Register Notices
      9. Proposed Revision on Subpart 1 Area Reclassification and Anti-Backsliding Provisions Under Former 1-Hour Ozone Standard; Proposed Deletion of Obsolete 1-Hour Ozone Standard Provision (January 16, 2009)      [ PDF ]
      10. Ozone (O3) Standards - Documents from Current Review - Federal Register Notices
    2. Other Associated Federal Register Notices
      1. Clean Air/Attainment Determinations
      2. Changes to a Higher Classification
      3. All Federal Register Notices
        1. Notices Listed By Category
        2. Notices Listed By Area Name
        3. Notices Listed By State then Area
        4. Notices Listed By Date

File Utilities

Local Navigation

Jump to main content.