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Draft Integrated Science Assessment for Oxides of Nitrogen and Sulfur-Environmental Criteria

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Environmental Protection Agency (EPA).


Notice of public comment period for draft Integrated Science Assessment for Oxides of Nitrogen and Sulfur—Environmental Criteria.


The EPA is announcing the public comment period for the draft document titled, “Integrated Science Assessment for Oxides of Nitrogen and Sulfur—Environmental Criteria; First External Review Draft” (EPA/600/R-07/145A). The draft document was prepared by the National Center for Environmental Assessment within EPA's Office of Research and Development as part of the Agency's review of the secondary (welfare-based) national ambient air quality standards (NAAQS) for nitrogen dioxide (NO2) and sulfur dioxide (SO2). EPA is releasing this draft document solely for the purpose of seeking comment from the public and the Clean Air Scientific Advisory Committee (CASAC). The document is being distributed solely for the purpose of pre-dissemination review under applicable information quality guidelines. It does not represent and should not be construed to represent any Agency policy, viewpoint, or determination. EPA will consider any public comments submitted in accordance with this notice when revising the document.


The public comment period begins on or about December 21, 2007. Comments must be received on or before February 21, 2008.


The draft, “Integrated Science Assessment for Oxides of Nitrogen and Sulfur—Environmental Criteria; First External Review Draft,” will be 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. Emily Lee by phone: 919-541-4169, fax: 919-541-1818, or e-mail: ( to request either of these, and please provide your name, your mailing address, and the draft document title, “Integrated Science Assessment for Oxides of Nitrogen and Sulfur—Environmental Criteria; First External Review Draft” (EPA/600/R-07/145A) to facilitate processing of your request. Comments may be submitted electronically via, by mail, by facsimile, or by hand delivery/courier. Please follow the detailed instructions provided in the SUPPLEMENTARY INFORMATION section of this notice.

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Ms. Emily Lee, NCEA; telephone: 919-541-4169, facsimile: 919-541-1818, or e-mail: For technical information, contact Tara Greaver, PhD, NCEA; telephone: 919-541-2435; facsimile: 919-541-1818; 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 “may reasonably be anticipated to endanger public health and 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 and welfare. EPA is also to revise the NAAQS, if appropriate, based on the revised air quality criteria.

Oxides of nitrogen and sulfur are two of six principal (or “criteria”) pollutants for which EPA has established air quality criteria and NAAQS. EPA periodically 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 a current NAAQS and the appropriateness of new or revised standards. The Clean Air Scientific Advisory Committee (CASAC), an independent science advisory committee established pursuant to section 109 of the Clean Air Act and part of the EPA's Science Advisory Board (SAB), provides Start Printed Page 72720independent scientific advice on NAAQS matters, including advice on EPA's draft ISAs.

EPA formally initiated its current review of the criteria for oxides of nitrogen and sulfur in December 2005 (70 FR 73236) and May 2006 (71 FR 28023) respectively, requesting the submission of recent scientific information on specified topics. In the initial stages of the criteria reviews, EPA recognized the merit of integrating the science assessment for these two pollutants due to their combined effects on atmospheric chemistry, deposition processes, and environment-related public welfare effects. In July 2007 (72 FR 34004), a workshop was held to discuss, with invited scientific experts, initial draft materials prepared in the development of the ISA and supplementary annexes for oxides of nitrogen and sulfur. EPA's “Draft Plan for Review of the Secondary National Ambient Air Quality Standards for Nitrogen Dioxide and Sulfur Dioxide” was made available in September 2007 for public comment and was discussed by the Clean Air Scientific Advisory Committee (CASAC) via a publicly accessible teleconference consultation on October 30, 2007 (72 FR 57568). The Plan is being finalized and will be made available on EPA's Web site​ttn/​naaqs/​standards/​no2so2sec/​cr_​pd.html.

The draft, “Integrated Science Assessment for Oxides of Nitrogen and Sulfur—Environmental Criteria; First External Review Draft,” will be discussed by CASAC at a future public meeting; public comments that have been received prior to the public meeting will be provided to the CASAC review panel. A future Federal Register notice will inform the public of the exact date and time of that CASAC meeting.

II. How To Submit Information to the Docket

Submit your comments, identified by Docket ID No. Docket ID EPA-HQ-OAR-2007-1145 by one of the following methods:

  • Follow the online 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, EPA West Building, Room 3334, 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 one unbound original with pages numbered consecutively, and 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-OAR-2007-1145. 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 that you consider to be CBI or otherwise protected through or e-mail. 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: All 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 material, such as copyrighted material, will be publicly available only in hard copy. Publicly available docket materials are available either electronically in or in hardcopy at the OEI Docket in the EPA Headquarters Docket Center.

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Dated: December 17, 2007.

Rebecca Clark,

Acting Director, National Center for Environmental Assessment.

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[FR Doc. E7-24906 Filed 12-20-07; 8:45 am]