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Cross-State Air Pollution Rule (CSAPR)

Cross-State Air Pollution Rule (CSAPR)

What's New
  • October 23, 2014 - The U.S. Court of Appeals for the D.C. Circuit ordered that EPA's motion to lift the stay of the Cross-State Air Pollution Rule be granted.
  • June 26, 2014 - The U.S. government filed a motion with the U.S. Court of Appeals for the D.C. Circuit to lift the stay of the Cross State Air Pollution Rule. While the Court considers the motion, CAIR remains in place and no immediate action from States or affected sources is expected.
  • April 29, 2014 -The U.S. Supreme Court reversed the D.C. Circuit opinion vacating CSAPR. EPA is reviewing the opinion.
  • September 4, 2013 - The United States filed its opening merits brief with the Supreme Court challenging the D.C. Circuit decision on CSAPR.
  • June 24, 2013 - The U.S. Supreme Court granted the United States' petition asking the Court to review the D.C. Circuit Court's decision on CSAPR.
  • More news...
  • On July 6, 2011, the US Environmental Protection Agency (EPA) finalized a rule that protects the health of millions of Americans by helping states reduce air pollution and attain clean air standards. This rule, known as the Cross-State Air Pollution Rule (CSAPR), requires states to significantly improve air quality by reducing power plant emissions that contribute to ozone and/or fine particle pollution in other states. In a separate, but related, regulatory action, EPA finalized a supplemental rulemaking on December 15, 2011 to require five states - Iowa, Michigan, Missouri, Oklahoma, and Wisconsin - to make summertime NOX reductions under the CSAPR ozone season control program. CSAPR requires a total of 28 states to reduce annual SO2 emissions, annual NOX emissions and/or ozone season NOX emissions to assist in attaining the 1997 ozone and fine particle and 2006 fine particle National Ambient Air Quality Standards (NAAQS). On February 7, 2012 and June 5, 2012, EPA issued two sets of minor adjustments to the Cross-State Air Pollution Rule (CSAPR).

    This rule replaces EPA's 2005 Clean Air Interstate Rule (CAIR). A December 2008 court decision kept the requirements of CAIR in place temporarily but directed EPA to issue a new rule to implement Clean Air Act requirements concerning the transport of air pollution across state boundaries. This action responds to the court's concerns.

    The Cross-State Air Pollution Rule provides cleaner air and healthier lives for millions of Americans

    Estimated Annual Number of Adverse Health Effects Avoided Due to Implementing the CSAPR*
    Health Effect Number of Cases Avoided
    Premature mortality 13,000 to 34,000
    Non-fatal heart attacks 15,000
    Hospital and emergency department visits 19,000
    Accute bronchitis 19,000
    Upper and lower respiratory symptoms 420,000
    Aggravated asthma 400,000
    Days when people miss work or school 1.8 million

    *Impacts avoided due to improvements in PM2.5 and ozone air quality in 2014

    The CSAPR will help avoid tens of thousands of premature deaths and illnesses, achieving hundreds of billions of dollars in public health benefits. Pollution reductions will also lead to improvements in visibility in national and state parks, and increased protection for sensitive ecosystems including Adirondack lakes and Appalachian streams, coastal waters and estuaries, and forests.

    Picture of a small circle representing costs inside of a large circle representing benefits. The benefits circle is larger than the costs circle, demostrating a good return on investment.

    The benefits of the Cross-State Air Pollution Rule far outweigh the costs of the rule.

    The final rule yields $120 to $280 billion in annual health and environmental benefits in 2014, including the value of avoiding 13,000 to 34,000 premature deaths. This far outweighs the estimated annual costs of CSAPR. The $800 million in annual projected costs of this rule in 2014, along with the roughly $1.6 billion per year in capital investments already under way as a result of CAIR, are improving air quality for over 240 million Americans. This rule will not disrupt a reliable flow of affordable electricity for American consumers and businesses. Health benefits will be achieved at a very low cost, and while the effect on prices for specific regions or states may vary, they are well within the range of normal electricity price fluctuations. Any such costs will be greatly outweighed by the benefits.

    The Cross-State Air Pollution Rule improves air quality throughout the eastern half of the United States, helping states achieve national clean air standards.

    Click on the map to see a larger image | View this map as a table

    Map of States covered by the Cross-State Air Pollution Rule (CSAPR)

    The rule requires significant reductions in sulfur dioxide (SO2) and nitrogen oxide (NOX) emissions that cross state lines. These pollutants react in the atmosphere to form fine particles and ground-level ozone and are transported long distances, making it difficult for other states to achieve NAAQS. To see how the rule affects each state in the CSAPR region, view the table "States that are included in the CSAPR" on the Resources for Implementation page.

    Emission reductions will take effect quickly, starting January 1, 2012 for SO2 and annual NOX reductions, and May 1, 2012 for ozone season NOX reductions. By 2014, combined with other final state and EPA actions, the Cross-State Air Pollution Rule will reduce power plant SO2 emissions by 73 percent and NOX emissions by 54 percent from 2005 levels in the CSAPR region.

    The emission reductions expected from EPA's recently-finalized Mercury and Air Toxics Standards (MATS) are not included in the estimated emission reductions from the Cross-State Air Pollution Rule; once those standards are implemented, SO2 emissions from the power sector are likely to be reduced even further.

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