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Cross-State Air Pollution Final and Proposed Rules

On July 6, 2011 the US Environmental Protection Agency (EPA) finalized the Cross-State Air Pollution Rule (CSAPR), limiting the interstate transport of emissions of nitrogen oxides (NOX) and sulfur dioxide (SO2) that contribute to harmful levels of fine particle matter (PM2.5) and ozone in downwind states.

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July 6, 2011: Final Cross-State Air Pollution Rule (CSAPR)

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.

Technical Support Documents

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January 7, 2011: Notice of Data Availability

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."

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October 27, 2010: Notice of Data Availability

Emissions inventories data supporting the CSAPR were made available for review.

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September 1, 2010: Notice of Data Availbility

EPA announced a Notice of Data Availability Supporting the Proposed Transport Rule


August 19 - September 1, 2010: Public Hearings

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

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July 6, 2010: Proposed Cross-State Air Pollution Rule (CSAPR)

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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Technical Support Documents:

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