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Area Designations for 1997 Fine Particle (PM2.5) Standards

Regulatory Actions

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This page contains a chronological listing of regulatory actions and correspondence related to the PM2.5 standard.

March 29, 2007: Clean Air Fine Particle Implementation Rule Will Help States Control Fine Particle Air Pollution

Final rule February 23, 2006: Transportation Conformity Rule That Addresses Requirements for Project-level Conformity Determinations in PM2.5 and PM10 Nonattainment and Maintenance Areas

January 20, 2006: EPA Completes Response to Petitions Requesting Reconsideration of Fine Particle Designations

December 5, 2005: EPA Upholds Fine Particle Pollution Designations

November 2005: Public Hearing and Comment Period Extended on Proposed Rule to Implement the Fine Particle National Air Quality Standards

September 8, 2005: Proposed Rule to Implement the Fine Particle National Air Quality Standards

April 5, 2005: Twelve Areas Attain National Air Quality Standards for Fine Particle Pollution

December 17, 2004: Areas Designated Nonattainment for the Fine Particle National Air Quality Standards

February 2004: Recommendations for Areas to be Designated "Nonattainment" for the Fine Particle National Air Quality Standards




Clean Air Fine Particle Implementation Rule Will Help States Control Fine Particle Air Pollution

On March 29, 2007, EPA issued a final rule defining requirements for state plans to clean the air in 39 areas where particle pollution levels do not meet national air quality standards. Fine particles or "PM2.5" can aggravate heart and lung diseases and have been associated with premature death and a variety of serious health problems including heart attacks, chronic bronchitis and asthma attacks. This rule will help state and tribal environmental agencies develop and implement plans that will improve air quality for millions of Americans.

Final Rule (PDF) (83 pp, 524KB)
Fact Sheet


EPA Completes Response to Petitions Requesting Reconsideration of Fine Particle Designations

On December 5, 2005, EPA delivered letters to seven state and local government petitioners denying their requests that the Agency reconsider its decision to designate one or more full or partial county within their jurisdiction as nonattainment for EPA’s health-based national air quality standards for fine particle pollution. EPA sent an eighth letter to a government/business coalition denying their request to stay the effective date of the designations.

On January 20, 2006, EPA delivered letters to five state and local government petitioners denying their requests that the agency reconsider its decision to designate one or more full or partial county within their jurisdiction as nonattainment for EPA's health-based national air quality standards for fine particle pollution. EPA sent a sixth letter to Dynegy Midwest Generation Corporation, denying their request to remove the part of Randolph County, IL included in the St. Louis, MO-IL nonattainment area.

On August 16, 2007, EPA sent a letter to representatives for the Midwest Ozone Group and the West Virginia Chamber of Commerce which denies their request that the Agency reconsider its decision to designate certain full or partial counties as nonattainment.

More information about state designations

Petitioner Petition EPA Response Response Date
State of Connecticut Letter (PDF) (3 pp, 168KB) Letter (PDF) (4 pp, 935KB) Dec 2005
Commonwealth of Virginia Letter (PDF) (8 pp, 496KB) Letter (PDF) (3 pp, 935KB) Dec 2005
State of Maryland Letter (PDF) (2 pp, 166KB)
Attachment (12 pp, 672KB)
Letter (PDF) (4 pp, 935KB) Dec 2005
Guilford County, NC Letter (PDF) (8 pp, 300KB) Letter 1 (PDF) (5 pp, 935KB)
Letter 2 (PDF) (5 pp, 935KB)
Dec 2005
State of North Carolina Letter (PDF) (3 pp, 123KB) Letter (PDF) (4 pp, 935KB) Dec 2005
State of Alabama Letter (PDF) (6 pp, 254KB) Letter (PDF) (3 pp, 945KB) Dec 2005
State of Georgia Letter (PDF) (4 pp, 498KB) Letter (PDF) (3 pp, 935KB) Dec 2005
Southwestern PA Growth Alliance Letter (PDF) (8 pp, 644KB)
Attachment 1 (PDF) (10 pp, 653KB)
Attachment 2 (PDF) (24 pp, 305KB)
Letter (PDF) (2 pp, 935KB) Dec 2005
Oakland Co, MI
(first petition)
Letter 1 (PDF) (83 pp, 404KB)
Letter 2 (PDF) (4 pp, 167KB)
Letter 3 (PDF) (4 pp, 159KB)
Letter (PDF) (32 pp, 298KB) Jan 2006
State of Michigan Letter (PDF) (12 pp, 864KB) Letter (PDF) (5 pp, 50KB) Jan 2006
State of West Virginia Letter (PDF) (2 pp, 110KB) Letter (PDF) (8 pp, 177KB) Jan 2006
State of Ohio Letter (PDF) (32 pp, 1.0MB) Letter (PDF) (2 pp, 24KB) Jan 2006
State of Georgia Letter (PDF) (7 pp, 69KB) Letter (PDF) (70 pp, 937KB) Jan 2006
Dynegy Midwest Generation Letter (PDF) (166 pp, 2.6MB) Letter (PDF) (9 pp, 91KB) Jan 2006
Midwest Ozone Group/West Virginia Chamber of Commerce Letter (PDF) (6 pp, 103KB) Letter (PDF) (18 pp, 1.2MB)
Attachment (35 pp, 648KB)
Aug 2007
Oakland Co, MI
(second petition)
Letter 1 (PDF) (1 p, 32KB)
Attachment (PDF) (78 pp, 2MB)
Letter 2 (PDF) (7 pp, 430KB)
Appendix 1 (PDF) (473 pp, 6.3MB)
Appendix 2 (PDF) (13 pp, 683KB)
Appendix 3 (PDF) (28 pp, 2.3MB)
Letter (PDF) (38 pp, 2.9MB) Sep 2007


Public Hearing and Comment Period Extended on Proposed Rule to Implement the Fine Particle National Air Quality Standards

EPA will hold a public hearing Wednesday, Nov. 30, 2005 on its proposed rule for the 1997 fine particle (PM2.5) national ambient air quality standards. The hearing, at the Capitol Hilton in Washington, D.C., will last from 9 a.m. to 5 p.m.

Federal Register notice on the comment period extension (PDF) (2 pp, 55KB)


Proposed Rule to Implement the Fine Particle National Air Quality Standardsrds

On September 8, 2005, the Environmental Protection Agency (EPA) issued a proposed rule implementing the 1997 fine particle (PM2.5) national ambient air quality standards. The Agency will accept public comment on this proposal for 60 days from the date the notice appears in the Federal Register.

Proposed Rule (PDF) (85 pp, 728KB)
Fact Sheet
How to Comment


Twelve Areas Attain National Air Quality Standards for Fine Particle Pollution

On April 5, 2005, designations under the national air quality standards for fine particle pollution or PM2.5 became effective. EPA announced its decision on these designations in December 2004.

Fact sheet
Press release
Supplemental notice (PDF) (13pp, 216k)
Map of nonattainment areas
Table showing final designations
Areas changed to attainment status
Sample nonattainment requirements
PM2.5 Timeline
Benefits of meeting the PM2.5 standards
Particle pollution trends through 2003
PM standards review


Areas Designated Nonattainment for the Fine Particle National Air Quality Standards

On December 17, 2004, EPA took final action to designate attainment and nonattainment areas under the more protective national air quality standards for fine particles.

Fact sheet
Final designations rule
  Preamble (PDF) (45 pp, 340KB)
  Part 81
Map of nonattainment areas
Table showing nonattainment designations


Recommendations for Areas to be Designated "Nonattainment" for the Fine Particle National Air Quality Standards

In mid-February 2004, states and tribes recommended areas to be designated as "nonattainment". Nonattainment areas are those areas with air quality levels exceeding the standards, plus nearby areas contributing to such violations. EPA revised these recommendations and responded to the states and tribes in June 2004.

Fact Sheet
Map of EPA responses to PM2.5 recommendations

Comparison of state recommendations and EPA responses
PM2.5 Timeline
Benefits of meeting the PM2.5 standard
National trends in PM2.5 air quality
PM2.5 standards review

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