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Fact Sheet - Final Amendments to the Regional Haze Rule and Guidelines for Best Available Retrofit Technology (BART) Determinations

printable version (PDF, 3 pp, 29 KB)


• On June 15, 2005, the Environmental Protection Agency (EPA) finalized amendments to the July 1999 regional haze rule. These amendments apply to the provisions of the regional haze rule that require emission controls known as best available retrofit technology, or BART, for industrial facilities emitting air pollutants that reduce visibility by causing or contributing to regional haze.

• The pollutants that reduce visibility include fine particulate matter (PM2.5), and compounds which contribute to PM2.5 formation, such as nitrogen oxides (NOx), sulfur dioxides (SO2), and under certain conditions volatile organic compounds, and ammonia.

• EPA evaluated three possible scenarios of actions the states may take to comply with this rule. Under the medium stringency scenario EPA estimates that BART controls will result in annual NOx reductions of about 600,000 tons. Emission reductions for SO2 will be approximately 400,000 tons annually.

• EPA’s benefits analysis estimates that the amendments will lead to significant improvements in visibility in southeastern and southwestern parks. Under the medium stringency scenario this rule will provide approximately $240 million in improved visibility benefits each year. In 2015, the final rule also will provide substantial health benefits valued at $8.4 - $9.8 billion annually -- preventing 1,600 premature deaths, 2,200 non-fatal heart attacks, 960 hospital admissions, and over 1 million lost school and work days. The total annual cost will range from 1.4 – 1.5 billion dollars.

• The BART requirements of the regional haze rule apply to facilities built between 1962 and 1977 that have the potential to emit more than 250 tons a year of visibility-impairing pollution. Those facilities fall into 26 categories, including utility and industrial boilers, and large industrial plants such as pulp mills, refineries and smelters. Many of these facilities previously have not been previously been subject to federal pollution control requirements for these pollutants.

• Under the 1999 regional haze rule, states are required to set periodic goals for improving visibility in the 156 natural areas. As states work to reach these goals, they must develop regional haze implementation plans that contain enforceable measures and strategies for reducing visibility-impairing pollution. Today’s amendments include guidelines, known as BART guidelines, for states to use in determining which facilities must install controls and the type of controls the facilities must use.

• States must develop their implementation plans by December, 2007. States will identify the facilities that will have to reduce emissions under BART and then set BART emissions limits for those facilities.

• States must consider a number of factors when determining what facilities will be covered by BART including:

    • the cost of the controls;
    • the impact of controls on energy usage or any non-air quality environmental impacts;
    • the remaining useful life of the equipment to be controlled;
    • any existing pollution controls already in place; and
    • visibility improvement that would result from controlling the emissions.

• The guidelines also explain:

    • How to identify the plants and equipment for which a BART analysis is required;
    • The circumstances under which a source may or may not be exempt from a detailed BART review;
    • The procedures for reviewing available emission control methods, and procedures for summarizing and reporting the results of this review; and
    • The type of air quality analysis that is needed to inform the state’s BART determination.
    • In a separate action EPA will propose additional revisions to the regional haze rule in the near future to address alternative emissions trading programs.

• On March 10, 2005, EPA issued the Clean Air Interstate Rule (CAIR), requiring reductions in emissions of SO2 and NOx from electricity generating units (EGUs) in 28 eastern States and the District of Columbia. When fully implemented, CAIR will reduce SO2 emissions in these states by over 70 percent and NOx emissions by over 60 percent from 2003 levels. The CAIR establishes an EPA-administered cap and trade program for EGUs in which States may participate as a means to meet these requirements. In the BART rule, EPA presents the results of an analysis showing that controls for EGUs subject to CAIR will result in more visibility improvement in natural areas than BART would have provided. Therefore, States which adopt the CAIR cap and trade program for SO2 and NOx are allowed to apply CAIR controls as a substitute for controls required under BART because our analysis concluded that CAIR controls are “better than BART” for EGUs in the states subject to CAIR.

• This rule will take effect 60 days after it is published in the Federal Register.


• Regional haze is a national problem caused by multiple sources over a wide area. Visibility is affected by different sources at different times of the year and under different weather conditions. Some other significant contributors to visibility impairment include car and truck emissions, area sources (broadly distributed and numerous small sources), wildfires, agricultural fires, and wind blown dust.

• The same pollution that causes haze also poses health risks for some people with chronic respiratory diseases.

• To reduce haze, and to meet requirements of the Clean Air Act, EPA in April 1999 issued a regional haze rule aimed at protecting visibility in 156 federal areas. The rule seeks to reduce the visibility impairment caused by many sources over a wide area. EPA’s previous visibility regulation, issued in 1980, addressed only local visibility impairment from local sources.

• Soon after the regional haze rule was finalized, several parties filed petitions to challenge the rule with the U.S. Court of Appeals for the D.C. Circuit.

• Because regional haze is a problem caused by multiple sources over a wide area, EPA's 1999 rule allowed states that were determining BART requirements to assess visibility impacts from multiple sources rather than on a source-by-source basis. In May 2002, the court ruled that aspects of EPA’s specific approach to this issue were not consistent with the Clean Air Act.

• On April 15, 2004 EPA reproposed a rule in response to the May 2002 ruling by the U.S. Court of Appeals for the D.C. Circuit vacating parts of the BART provisions of the regional haze rule (American Corn Growers et al. v. EPA, 291 F. 3d 1 (D.C. cir. 2002)).

• EPA initially proposed BART guidelines on July 20, 2001, but did not finalize that proposal, in light of the 2002 Court ruling.

• The 2004 proposal provided a process by which states can consider an individual facility’s contribution to regional haze when determining whether to require controls, and what the level of control should be.

• For large electric generating units, this rule recommends specific emissions limits for nitrogen oxides and sulfur dioxide.


• A copy of this notice and a copy of the Regional Haze rule is available at http://www.epa.gov/visibility

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