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Green Book

Green Book Early Action Compact (EAC) Areas

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.Fourteen areas were listed in 40 CFR Part 81 Subpart C as participating in an Early Action Compact (EAC) and designated nonattainment with a deferred effective date.

  1. Area Listings Sorted by
    1. Classification
    2. State/Area/County
    3. Area/State/County

  2. Area Maps
    1. U.S. Map

  3. Area Designation Data
    1. Data

  4. Area Summary Report


On June 15, 2005 the 1-Hour Ozone standard was revoked for all areas except the 8-Hour Ozone nonattainment Early Action Compact (EAC) areas. This happened by virtue of 40 CFR 50.9(b). Due to the revocation of the 1-Hour Ozone standard, effective June 15, 2005 (70 FR 44470), 1-Hour Ozone designations and classifications were removed for all areas except EAC areas that had deferred effective dates for their designations under the 8-Hour Ozone 1997 standard.  
See 70 FR 44470

By April 2008, 13 of the areas were designated attainment when they met all of their EAC requirements and had clean 8-Hour Ozone (1997) data by December 31, 2007.

The Denver-Boulder-Greeley-Ft Collins-Loveland, Colorado Subpart 1 EAC area, was designated nonattainment for 8-Hour Ozone, effective November 20, 2007 (72 FR 53952), based on air quality data from 2005, 2006 and the first three quarters of 2007. For Denver, the 1-Hour standard was revoked November 20, 2008. 
See 72 FR 53952

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. 

Current Status

On April 2, 2008, EPA finalized (73 FR 17897) the designation of the remaining 13 Early Action Compact (EAC) Areas as attainment for the 8-Hour Ozone (1997) National Ambient Air Quality Standards (NAAQS), effective April 15, 2008. The States in which these 13 areas are located had submitted quality-assured data indicating that the areas are in attainment for the 8-Hour Ozone NAAQS based on ambient air monitoring data from 2005, 2006 and 2007.

In addition, consistent with EPA's implementing regulations, the 1-Hour Ozone NAAQS no longer applied in each of these areas one year after the effective date of the designation. The 8-Hour Ozone (1997) NAAQS tables were modified in the regulations to reflect the attainment designation for the 13 EAC areas and the 1-Hour Ozone NAAQS tables in the regulations to reflect that the 1-Hour standard no longer applies in these areas as of April 15, 2009. 
See: 73 FR 17897