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Cross-State Air Pollution Rule

Regulatory Actions

The U.S. Court of Appeals for the D.C. Circuit issued its ruling on CSAPR. EPA is reviewing the court decision. CAIR remains in place.

June 5, 2012 - EPA issued the final set of minor adjustments to the Cross-State Air Pollution Rule (CSAPR). This final rule will help sources comply with the program by increasing state budgets for Arkansas, Georgia, Indiana, Kansas, Louisiana, Mississippi, Missouri, Nebraska, New York, Ohio, Oklahoma, South Carolina, and Texas. This rule also revises new unit set-asides for Arkansas, Louisiana, and Missouri.

May 11, 2012 - On May 10, 2012, EPA withdrew the Direct Final Revisions Rule (77 FR 10342, February 21, 2012). The Agency issued a parallel proposal (77 FR 10350, February 21, 2012) along with the direct final rule proposing the same revisions and will take final action on the proposed revisions rule expeditiously. The withdrawal does not affect the Final CSAPR Revisions Rule (77 FR 10324, February 21, 2012). Exit EPA Disclaimer

April 20, 2012 - EPA has reviewed the comments submitted in response to the Direct Final Revisions Rule. EPA intends to withdraw the Direct Final Revisions Rule prior to its effective date and take final action on the proposed revisions rule expeditiously.

February 7, 2012 - EPA issued two sets of minor adjustments to the Cross-State Air Pollution Rule (CSAPR). These final rules maintain the significant health benefits of CSAPR, while making minor technical adjustments based on the latest and best data to ensure a smooth transition for utilities. The adjustments provide flexibility to states by increasing budgets in seventeen states and easing limits on market-based compliance options.

    Final Revisions Rule
    The final revisions rule will enhance compliance flexibility and smooth the transition from the Clean Air Interstate Rule (CAIR) programs to the CSAPR programs.

    Direct Final Rule
    In a separate but related rule, EPA is taking direct final action on several additional revisions to provide consistent technical adjustments to the CSAPR.

December 15, 2011 - EPA finalized a supplemental rule that includes five additional states - Iowa, Michigan, Missouri, Oklahoma, and Wisconsin - in the ozone season NOX program in the Cross-State Air Pollution Rule (CSAPR). EPA has concluded that these five states plus Kansas significantly contribute to nonattainment and/or interference with maintenance of the 1997 ozone NAAQS in other states.

  • Supplemental Notice of Final Rulemaking Federal Register (76 FR 80760, December 27, 2011) (PDF 18pp) Exit EPA Disclaimer
  • Fact Sheet (PDF 3pp, 80 KB)
  • Presentation (PDF 33pp, 1.80 MB) Updated December 15, 2011 to reflect the final supplemental rule for CSAPR, the proposed technical revisions rule, recent implementation activities, and other information.

October 6, 2011 - EPA is proposing technical adjustments to the final Cross-State Air Pollution Rule (CSAPR). CSAPR is a sound, achievable, market-based program that will deliver strong public health protections. No changes are being proposed or contemplated to the core elements of the program. The proposed revisions will not affect the significant air quality improvements slated to occur under CSAPR, nor have a major impact on CSAPR's goal to reduce interstate transport of pollution to help downwind states in their efforts to attain and maintain the National Ambient Air Quality Standards (NAAQS).

July 6, 2011 - EPA finalized a rule that protects the health of millions of Americans by helping states reduce air pollution and meet Clean Air Act Standards. The Cross-State Air Pollution Rule (CSAPR) requires eastern and central states to significantly improve air quality by reducing power plant emissions that cross state lines and contribute to ground-level ozone and fine particle pollution in other states.

In a separate but related regulatory action, EPA also issued a supplemental notice of proposed rulemaking to require six states: Iowa, Kansas, Michigan, Missouri, Oklahoma, and Wisconsin to make summertime NOX reductions under the CSAPR ozone-season control program.

EPA also issued a "Notice of Data Availability Concerning Transport Rule Allowance Allocations to Existing Units" informing the public of the availability of detailed unit-by-unit data, calculations, and allowance allocation determinations in a technical support document for the final Cross State Air Pollution Rule. EPA is not requesting comments on the data made available through this NODA.

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Final Cross-State Air Pollution Rule (CSAPR)

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Supplemental Notice of Proposed Rulemaking

EPA received some requests to extend the comment period for the supplemental notice of proposed rulemaking (SNPR) related to the Cross-State Air Pollution Rule. The comment period on this rule ended on August 22, 2011. The supplemental proposal and all of the key supporting documentation and model results were posted on our website on July 7, 2011 and the SNPR was formally published in the Federal Register on July 11, 2011. We believe the comment period provided was sufficient for interested parties to review the supplemental proposal, and to prepare and submit public comment that was within the scope of the issues presented for public comment in the SNPR. As such, EPA has not extended the public comment period for this rulemaking.

Notice of Data Availability

*For annual SO2 and NOX allocations, tables include sources located in states covered by the CSAPR. For ozone-season allocations, tables include sources located in states covered by the final CSAPR as well as the 6 states that are included in the Supplemental Notice of Proposed Rulemaking for ozone-season NOX emission reductions.

Disclaimer: The official version of these documents will be in the docket when the rule is published in the Federal Register.

January 7, 2011 - EPA issued a "Notice of Data Availability For Federal Implementation Plans To Reduce Interstate Transport of Fine Particulate Matter and Ozone: Request for Comment on Alternative Allocations, Calculation of Assurance Provisions Allowance Surrender Requirements, New-Unit Allocations in Indian Country and Allocations by States".

October 27, 2010 - Emissions inventories data supporting the CSAPR were made available for review.

September 17, 2010 - EPA received and declined several requests to extend the comment period for the proposed Transport Rule. The comment period on this rule ended on October 1, 2010. The proposed rule and much of the key supporting documentation were posted on our website on July 6, 2010 and the rule was formally published in the Federal Register on August 2, 2010. We believe the comment period provided was sufficient for interested parties to review the rule, and prepare and submit input. This time frame allowed EPA to consider public comments and develop a final rule in time to obtain needed emissions reductions.

September 1, 2010 - EPA announced a Notice of Data Availability Supporting the Proposed Transport Rule

August 2, 2010 - EPA held three public hearings on the proposed Transport Rule. Each hearing began at 9 a.m. and continued until 8 p.m. The public was able to preregister to speak at the hearings at a specific time, or they could register in person on the day of the hearing and were worked in to openings in the schedule of speakers.

Federal Register Notice announcing public hearings (PDF) (2pp, 47k)Exit EPA Disclaimer

July 6, 2010 - EPA proposed a rule that would significantly reduce emissions that contribute to fine particle and ozone pollution in the eastern United States.

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