Area Designations for 1997 Fine Particle (PM2.5) Standards
Note: EPA no longer updates this information, but it may be useful for historical purposes. See the PM Designations Home Page for more recent information about PM Designations.
FINAL CLEAN AIR FINE PARTICLE IMPLEMENTATION RULE
For Implementation of 1997 PM2.5 Standards
- On March 29, 2007, the Environmental Protection Agency (EPA) issued a rule defining requirements for state plans to clean the air in areas with levels of fine particle pollution that do not meet national air quality standards. State plans under this final rule, known as the Clean Air Fine Particle Implementation Rule, are the next step toward improving air quality for millions of Americans.
- EPA first established air quality standards for fine particles (PM2.5 – particles 2.5 micrometers in diameter and smaller) in 1997. After sufficient monitoring data was collected by state, local and tribal governments, EPA designated areas as “attainment” or “nonattainment” for the PM2.5 standards. These designations became effective in April 2005.
- Once an area is designated as nonattainment, the Clean Air Act requires the state to submit an implementation plan to EPA within three years. For the 1997 fine particle standards, state plans are due in April 2008. A Tribal area designated as not attaining the standards may submit an implementation plan. If they elect not to do so, the law requires EPA to develop an implementation plan on their behalf.
- This final rule describes the Clean Air Act framework and requirements that state, local, and tribal governments must meet in developing their PM2.5 implementation plans. An implementation plan includes rules and programs to reduce air pollutant emissions, and a demonstration that the area will meet the air quality standard within the time provided in the statute. The plan must include supporting technical analyses and any adopted state regulations as needed. State, local, and tribal plans must be reviewed and approved by EPA.
- States must meet the PM2.5 standard by 2010. However, in their 2008 implementation plans, states may propose an attainment date extension for up to five years. Those areas for which EPA approves an extension must achieve clean air as soon as possible, but no later than 2015.
- Key issues addressed in the rule:
- Reasonably available control measures (RACM) and reasonably available control technology (RACT) -- For each nonattainment area, the Clean Air Act requires the state to demonstrate that it has adopted all reasonably available control measures, considering economic and technical feasibility and other factors, that are needed to show that the area will attain the fine particle standards as expeditiously as practicable. This rule sets forth guidelines for making RACM and RACT determinations. The rule includes a presumption that for power plants subject to the Clean Air Interstate Rule (CAIR), compliance with CAIR would satisfy these requirements for sulfur dioxide and nitrogen oxides (with certain conditions).
- Attainment demonstrations and modeling – This final rule provides guidance on the required elements of an attainment demonstration, the recommended analytical process to follow to identify the most expeditious attainment date for an area, and guidance on air quality modeling.
- Policies on PM2.5 and precursors – Five main types of pollutants contribute to fine particle concentrations: direct PM2.5 emissions; sulfur dioxide; nitrogen oxides; ammonia; and volatile organic compounds. However, the effect of reducing emissions of each of these pollutants varies by area, depending on the fine particle composition, emission levels, and other area-specific factors. For this reason, the final rule establishes the following policies for evaluating and controlling sources of these emissions:
- PM2.5 direct emissions (including organic carbon, elemental carbon and crustal material) must be evaluated for emission reduction measures in all nonattainment areas.
- Sulfur dioxide must be evaluated for emission reduction measures in all nonattainment areas.
- Nitrogen oxides (NOx) must be evaluated for emission reduction measures in each area unless the state and EPA demonstrate that NOx is not a significant contributor to PM2.5 concentrations in a specific area.
- Volatile organic compounds are not required to be evaluated for emission reduction measures in each area unless the state or EPA demonstrates that VOCs significantly contribute to PM2.5 concentrations in a specific area.
- Ammonia is not required to be evaluated for emission reduction measures in each area unless the state or EPA demonstrates that ammonia significantly contributes to PM2.5 concentrations in a specific area.
- The final rule provides guidance on the types of analyses that may be included in a technical demonstration to reverse any of the presumptive precursor policies described above.
- The Bush Administration’s clean air strategy includes the introduction of ultra-low sulfur diesel fuel and clean diesel trucks and buses, the Clean Air Nonroad Diesel Rule to reduce pollution from nonroad diesel engines and the Clean Air Interstate Rule to reduce pollution from power plants in the eastern U.S. These federal programs will help all areas of the country meet the particle pollution standards.
- In September 2006, EPA issued revised national air quality standards for fine particle pollution. EPA significantly strengthened the previous daily fine particle standard from 65 micrograms of particles per cubic meter to 35 micrograms of particles per cubic meter of air. This standard increases protection of the public from short-term exposure to fine particles. The Clean Air Fine Particle Implementation Rule does not specifically address implementation of this recently revised standard.
FOR FURTHER INFORMATION
- Scientific studies have found an association between exposure to particulate matter and significant health problems, including: aggravated asthma; chronic bronchitis; reduced lung function; irregular heartbeat; heart attack; and premature death in people with heart or lung disease.
- Individuals particularly sensitive to fine particle exposure include older adults, people with heart and lung disease, and children.
- In July 1997, EPA promulgated the National Ambient Air Quality Standards for Fine Particles (PM-2.5). The annual standard is a level of 15 micrograms per cubic meter, based on the 3-year average of annual mean PM2.5 concentrations. The 24-hour standard is a level of 65 micrograms per cubic meter, based on the 3-year average of the 98th percentile of 24-hour concentrations.
- A number of events delayed the implementation of the 1997 PM-2.5 standard.
- EPA's 1997 standards were challenged by the American Trucking Association, the U.S. Chamber of Commerce and other state and business groups.
- In February 2001, the Supreme Court upheld EPA's authority under the Clean Air Act to set National Ambient Air Quality Standards that protect the American public from harmful effects of air pollution. The Supreme Court also sent the case back to the D.C. Circuit Court of Appeals to resolve several additional issues. In March 2002, the DC Circuit Court rejected all remaining legal challenges to EPA's 1997 ambient air quality standards for PM-2.5.
- The Transportation Equity Act for the Twenty-first Century revised the deadline to publish nonattainment designations in order to provide additional time to collect three years of air quality monitoring data.
- In April 2005, designations became effective for 39 metropolitan areas not attaining the 1997 fine particle standards. These areas include all or part of 208 counties, with a population of 88 million.
- Interested parties can download the notice from EPA's web site on the Internet at: https://www.epa.gov/pm/.
- Today’s action and other background information are also available electronically from www.regulations.gov, EPA’s electronic public docket and comment system, or in hard copy at EPA’s Air and Radiation Docket and Information Center, Environmental Protection Agency, Room 3334 Constitution Avenue, NW, Washington, D.C., (Docket ID No. EPA-HQ-OAR-2003-0062). The Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. The telephone number for the Public Reading Room is (202) 566-1744, and the telephone number for the Air and Radiation Docket and Information Center is (202) 566-1742.
- This final rule does not include new source review (NSR) requirements for the PM2.5 standards. These requirements will be addressed in a separate rulemaking. For more information, contact Raj Rao at (919) 541-5344, firstname.lastname@example.org.
- For additional information, visit the EPA’s website at: https://www.epa.gov/air/particles/implement.html or contact the following individuals at the EPA’s Office of Air Quality Planning and Standards: Rich Damberg (919) 541-5592, email@example.com.