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Extension of Public Comment Period: Second External Review Draft Integrated Science Assessment for Particulate Matter

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Environmental Protection Agency (EPA).


Extension of public comment period.


The EPA is announcing an extension of the public comment period for the draft document titled, “Integrated Science Assessment for Particulate Matter—Second External Review Draft” (EPA/600/R-08/139B and EPA/600/R-08/139BA). The document was prepared by the National Center for Environmental Assessment (NCEA) within EPA's Office of Research and Development as part of the review of the national ambient air quality standards (NAAQS) for particulate matter.

On July 31, 2009 (74 FR 38185), EPA released this draft document to seek review by the Clean Air Scientific Advisory Committee (CASAC) and the public (meeting date and location to be specified in a separate Federal Register notice). The draft document does not represent and should not be construed to represent any final EPA policy, viewpoint, or determination. EPA will consider any public comments submitted in response to this notice when revising the document.


The public comment period started on July 31, 2009 (74 FR 38185). This notice announces the extension of the deadline for public comment from September 30, 2009, to October 12, 2009. Comments must be received on or before October 12, 2009.


The “Second External Review Draft Integrated Science Assessment for Particulate Matter” is available primarily via the Internet on the National Center for Environmental Assessment's home page under the Recent Additions and Publications menus at​ncea. A limited number of CD-ROM or paper copies will be available. Contact Ms. Debbie Wales by phone (919-541-4731), fax (919-541-5078), or e-mail ( to request either of these, and please provide your name, your mailing address, and the document title, “Second External Review Draft Integrated Science Assessment for Particulate Matter” (EPA/600/R-08/139B and EPA/600/R-08/139C) to facilitate processing of your request.

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For technical information, contact Dr. Lindsay Wichers Stanek, NCEA; telephone: 919-541-7792; fax: 919-541-2985; or e-mail:

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I. Information About the Document

Section 108(a) of the Clean Air Act directs the Administrator to identify certain pollutants which, among other things, “cause or contribute to air pollution which may reasonably be anticipated to endanger public health or welfare” and to issue air quality criteria for them. These 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. * * *” Under section 109 of the Act, EPA is then to establish national ambient air quality standards (NAAQS) for each pollutant for which EPA has issued criteria. Section 109(d) of the Act subsequently requires periodic review and, if appropriate, revision of existing air quality criteria to reflect advances in scientific knowledge on the effects of the pollutant on public health or welfare. EPA is also to revise the NAAQS, if appropriate, based on the revised air quality criteria.

Particulate matter (PM) is one of six “criteria pollutants” for which EPA has established NAAQS. Periodically, EPA reviews the scientific basis for these standards by preparing an Integrated Science Assessment (ISA) (formerly called an Air Quality Criteria Document). The ISA and supplementary annexes, in conjunction with additional technical and policy assessments, provide the scientific basis for EPA decisions on the adequacy of the current NAAQS and the appropriateness of possible alternative standards. The Clean Air Scientific Advisory Committee (CASAC), an independent science advisory committee whose existence and whose review and advisory functions are mandated by Section 109(d)(2) of the Act, is charged (among other things) with independent scientific review of EPA's air quality criteria.

On June 28, 2007 (72 FR 35462), EPA formally initiated its current review of the air quality criteria for PM, requesting the submission of recent scientific information on specified topics. A draft of EPA's “Integrated Review Plan for the National Ambient Air Quality Standard for Particulate Matter” (EPA/452/P-08-006) was made available in October 2007 for public comment and was discussed by the CASAC PM Review Panel via a publicly accessible teleconference consultation on November 30, 2007 (72 FR 63177). EPA finalized the plan and made it available in March 2008 (EPA/452/R-08-004;​ttn/​naaqs/​standards/​pm/​s_​pm_​2007_​pd.html). In June 2008 (73 FR 30391), EPA held a workshop to discuss, with invited scientific experts, initial draft materials prepared in the development of the PM ISA and its supplementary annexes.

The First External Review Draft ISA for PM (EPA/600/R-08/139 and EPA/600/R-08/139A;​ncea/​cfm/​recordisplay.cfm?​deid=​201805) was released on December 22, 2008 (73 FR 77686). This document was reviewed by the CASAC and discussed at a public meeting on April 1 and 2, 2009 (74 FR 7688). The CASAC held a follow-up public teleconference on May 7, 2009 (74 FR 18230) to review and approve the CASAC PM Review Panel's draft letter providing comments to the Agency on the First External Review Draft ISA for PM (​sab/​Start Printed Page 44843sabproduct.nsf/​73ACCA834AB44A10852575BD0064346B/​$File/​EPA-CASAC-09-008-unsigned.pdf).

The Second External Review Draft ISA for PM was released on July 31, 2009 (74 FR 38185), and an updated version was posted on August 13, 2009 that included linkage of references in all chapters and annexes. The updated version of the draft ISA also included corrections to formatting issues in the text and some figures, but no substantive changes were made. In addition, the annexes were posted on August 13, 2009. The Second External Review Draft ISA for PM will be reviewed and discussed by CASAC at a public meeting. A future Federal Register notice will inform the public of the exact date and time of that CASAC meeting.

II. How To Submit Technical Comments to the Docket at

Submit your comments, identified by Docket ID No. EPA-HQ-ORD-2007-0517, by one of the following methods:

  • Follow the on-line instructions for submitting comments.
  • E-mail:
  • Fax: 202-566-1753.
  • Mail: Office of Environmental Information (OEI) Docket (Mail Code: 2822T), U.S. Environmental Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460. The phone number is 202-566-1752.
  • Hand Delivery: The OEI Docket is located in the EPA Headquarters Docket Center, Room 3334 EPA West Building, 1301 Constitution Ave., NW., Washington, DC. The EPA Docket Center Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. The telephone number for the Public Reading Room is 202-566-1744. Such deliveries are only accepted during the docket's normal hours of operation, and special arrangements should be made for deliveries of boxed information.

If you provide comments by mail or hand delivery, please submit three copies of the comments. For attachments, provide an index, number pages consecutively with the comments, and submit an unbound original and three copies.

Instructions: Direct your comments to Docket ID No. EPA-HQ-ORD-2007-0517. Please ensure that your comments are submitted within the specified comment period. Comments received after the closing date will be marked “late,” and may only be considered if time permits. It is EPA's policy to include all comments it receives in the public docket without change and to make the comments available online at, including any personal information provided, unless a comment includes information claimed to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Do not submit information through or e-mail that you consider to be CBI or otherwise protected. The Web site is an “anonymous access” system, which means EPA will not know your identity or contact information unless you provide it in the body of your comment. If you send an e-mail comment directly to EPA without going through, your e-mail address will be automatically captured and included as part of the comment that is placed in the public docket and made available on the Internet. If you submit an electronic comment, EPA recommends that you include your name and other contact information in the body of your comment and with any disk or CD-ROM you submit. If EPA cannot read your comment due to technical difficulties and cannot contact you for clarification, EPA may not be able to consider your comment. Electronic files should avoid the use of special characters, any form of encryption, and be free of any defects or viruses. For additional information about EPA's public docket visit the EPA Docket Center homepage at​epahome/​dockets.htm.

Docket: Documents in the docket are listed in the index. Although listed in the index, some information is not publicly available, e.g., CBI or other information whose disclosure is restricted by statute. Certain other materials, such as copyrighted material, are publicly available only in hard copy. Publicly available docket materials are available either electronically in or in hard copy at the OEI Docket in the EPA Headquarters Docket Center.

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Dated: August 18, 2009.

Rebecca Clark,

Acting Director, National Center for Environmental Assessment.

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[FR Doc. E9-20921 Filed 8-28-09; 8:45 am]