Skip to main content
U.S. flag

An official website of the United States government

Here’s how you know

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

HTTPS

Secure .gov websites use HTTPS
A lock (LockA locked padlock) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

    • Environmental Topics
    • Air
    • Bed Bugs
    • Cancer
    • Chemicals, Toxics, and Pesticide
    • Emergency Response
    • Environmental Information by Location
    • Health
    • Land, Waste, and Cleanup
    • Lead
    • Mold
    • Radon
    • Research
    • Science Topics
    • Water Topics
    • A-Z Topic Index
    • Laws & Regulations
    • By Business Sector
    • By Topic
    • Compliance
    • Enforcement
    • Laws and Executive Orders
    • Regulations
    • Report a Violation
    • Environmental Violations
    • Fraud, Waste or Abuse
    • About EPA
    • Our Mission and What We Do
    • Headquarters Offices
    • Regional Offices
    • Labs and Research Centers
    • Planning, Budget, and Results
    • Organization Chart
    • EPA History

Breadcrumb

  1. Home
  2. Green Book

Green Book Early Action Compact (EAC) Areas


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. EAC Data

  4. Area Summary Report

History

On June 15, 2005 the 1-Hour Ozone standard was revoked for all areas except the 8-Hour Ozone nonattainment Early Action Compact (EAC) areas.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

Green Book

  • 8-Hour Ozone (2015)
  • 8-Hour Ozone (2008)
  • 8-Hour Ozone (1997)
  • 1-Hour Ozone (1979)
  • PM-2.5 (2012)
  • PM-2.5 (2006)
  • PM-2.5 (1997)
  • PM-10 (1987)
  • Sulfur Dioxide (2010)
  • Sulfur Dioxide (1971)
  • Lead (2008)
  • Lead (1978)
  • Carbon Monoxide (1971)
  • Nitrogen Dioxide (1971)
  • Multi-Pollutant
  • Downloads
  • FAQ
  • Related Links
  • Recent Updates
Contact Us about Green Book
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on March 27, 2025
  • Assistance
  • Spanish
  • Arabic
  • Chinese (simplified)
  • Chinese (traditional)
  • French
  • Haitian Creole
  • Korean
  • Portuguese
  • Russian
  • Tagalog
  • Vietnamese
United States Environmental Protection Agency

Discover.

  • Accessibility Statement
  • Budget & Performance
  • Contracting
  • EPA www Web Snapshot
  • Grants
  • No FEAR Act Data
  • Plain Writing
  • Privacy
  • Privacy and Security Notice

Connect.

  • Data
  • Inspector General
  • Jobs
  • Newsroom
  • Regulations.gov
  • Subscribe
  • USA.gov
  • White House

Ask.

  • Contact EPA
  • EPA Disclaimers
  • Hotlines
  • FOIA Requests
  • Frequent Questions
  • Site Feedback

Follow.