Release of Final Documents Related to the Review of the National Ambient Air Quality Standards for Particulate Matter

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Notice of Availability.

SUMMARY:

The Office of Air Quality Planning and Standards (OAQPS) of EPA is announcing the availability of two final documents titled, Quantitative Health Risk Assessment for Particulate Matter and Particulate Matter Urban-Focused Visibility Assessment. These two documents describe the quantitative analyses that have been conducted as part of the review of the national ambient air quality standards (NAAQS) for particulate matter (PM).

DATES:

These documents will be available on or about June 30, 2010.

ADDRESSES:

The documents will be available primarily via the Internet at the following Web site: http://www.epa.gov/ttn/naaqs/standards/pm/s_pm_2007_risk.html.

FOR FURTHER INFORMATION CONTACT:

For questions related to the final document titled, Quantitative Health Risk Assessment for Particulate Matter, please contact Dr. Zachary Pekar, Office of Air Quality Planning and Standards (Mail code C504-06), U.S. Environmental Protection Agency, Research Triangle Park, NC 27711; e-mail: pekar.zachary@epa.gov; telephone: 919-541-3704; fax: 919-541-0237.

For questions related to the final document titled, Particulate Matter Urban-Focused Visibility Assessment, please contact Ms. Vicki Sandiford, Office of Air Quality Planning and Standards (Mail code C504-06), U.S. Environmental Protection Agency, Research Triangle Park, NC 27711; e-mail: sandiford,vicki@epa.gov; telephone: 919-541-2629; fax: 919-541-0237.

SUPPLEMENTARY INFORMATION:

Under section 108(a) of the Clean Air Act (CAA), the Administrator identifies and lists certain pollutants which “cause or contribute to air pollution which may reasonably be anticipated to endanger public health or welfare.” The EPA then issues air quality criteria for these listed pollutants, which are commonly referred to as “criteria pollutants.” The air quality criteria are to “accurately reflect the latest scientific knowledge useful in indicating the kind and extent of all identifiable effects on public health or welfare which may be expected from the presence of [a] pollutant in the ambient air, in varying quantities.” Under section 109 of the CAA, EPA establishes primary (health-based) and secondary (welfare-based) NAAQS for pollutants for which air quality criteria are issued. Section 109(d) of the CAA requires periodic review and, if appropriate, revision of existing air quality criteria. The revised air quality criteria reflect advances in scientific knowledge on the effects of the pollutant on public health or welfare. The EPA is also required to periodically review and revise the NAAQS, if appropriate, based on the revised criteria.

Presently, EPA is reviewing the NAAQS for PM. The EPA's overall plan and schedule for this review is presented in the Integrated Review Plan for the National Ambient Air Quality Standards for Particulate Matter. A draft of this integrated review plan was released for public review and comment in October 2007 and was the subject of a consultation with the Clean Air Scientific Advisory Committee (CASAC) on November 30, 2007 (72 FR 63177; November 8, 2007). Comments received from that consultation and from the public were considered in finalizing the plan and in beginning the review of the air quality criteria.

As part of EPA's review of the primary and secondary PM NAAQS, the Agency conducted quantitative assessments characterizing: (1) The health risks associated with exposure to ambient PM, and (2) urban visibility impairment associated with ambient PM. The EPA's plans for conducting these assessments, including the proposed scope and methods of the analyses, were presented in two planning documents titled, Particulate Matter National Ambient Air Quality Standards: Scope and Methods Plan for Health Risk and Exposure Assessment and Particulate Matter National Ambient Air Quality Standards: Scope and Methods Plan for Urban Visibility Impact Assessment (henceforth, Scope and Methods Plans). These documents were released for public comment in February 2009 and were the subject of a consultation with the CASAC on April 2, 2009 (74 FR 11580; March 18, 2009).

First and second external review drafts of the assessment documents were released for CASAC review and public comment in September 2009 (74 FR 46589; September 10, 2009) and January/February 2010 (75 FR 4067; January 26, 2010), respectively, and were the subjects of CASAC review meetings in October 2009 (74 FR 46586; September 10, 2009) and March 2010 (75 FR 8062; February 23, 2010), respectively. In preparing the final assessment documents, EPA has considered comments received from CASAC and the public on these earlier draft documents. The final assessment documents announced today convey the approaches taken to assess PM-related human health risks and urban visibility impairment, as well as present key results, observations, and related uncertainties associated with the quantitative analyses performed. These documents will be available on or about June 30, 2010, through the Agency's Technology Transfer Network (TTN) Web site at http://www.epa.gov/ttn/naaqs/standards/pm/s_pm_2007_risk.html.