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Guidance for 1-Hour SO2

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Environmental Protection Agency (EPA).


Notice of availability and public comment period.


Notice is hereby given that the EPA has posted its draft non-binding guidance titled, “Guidance for 1-Hour SO2 NAAQS SIP Submissions” on its Web site. The EPA invites public comments on this guidance document during the comment period specified below, and plans to issue an updated version of the guidance after reviewing timely submitted comments.


Comments should be submitted on or before November 2, 2011. Please refer to SUPPLEMENTARY INFORMATION for additional information on the comment period.


Submit your comments, identified by Docket ID No. EPA-HQ-OAR-2010-1059, by one of the following methods:

  • Follow the on-line instructions for submitting comments.
  • E-mail: Attention Docket ID No. EPA-HQ-OAR-2010-1059.
  • Fax: 202-566-9744. Attention Docket ID No. EPA-HQ-OAR-2010-1059.
  • Mail: Air Docket, Attention Docket ID No. EPA-HQ-OAR-2010-1059, Environmental Protection Agency, Mail Code: 6102T, 1200 Pennsylvania Ave., NW., Washington, DC 20460.
  • Hand Delivery: EPA Docket Center, 1301 Constitution Avenue, NW., Room 3334, Washington, DC. Such deliveries are only accepted during the Docket Start Printed Page 61099Center's normal hours of operation, and special arrangements should be made for deliveries of boxed information.

Instructions: Direct your comments to Docket ID No. EPA-HQ-OAR-2010-1059. The EPA's policy is that all comments received will be included in the public docket without change and may be made available online at, including any personal information provided, unless the 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 is unable to read your comment and contact you for clarification due to technical difficulties, 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. For additional instructions on submitting comments, go to Section II of the SUPPLEMENTARY INFORMATION section of this document.

Docket: All documents in the docket are listed in the index. Although listed in the index, some information is not publicly available, i.e., CBI or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, is not placed on the Internet and will be publicly available only in hard copy form. Publicly available docket materials are available either electronically in or in hard copy at the EPA Docket Center, EPA West, Room 3334, 1301 Constitution Avenue, NW., Washington, DC. The 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, and the telephone number for the Air Docket is (202) 566-1742.

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For questions concerning this action, please contact Larry D. Wallace, Ph.D., U.S. EPA, Office of Air Quality Planning and Standards, Air Quality Policy Division, C504-03, Research Triangle Park, NC 27711, telephone (919) 541-0906, e-mail at

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I. General Information

A. What should I consider as I prepare my comments for EPA?

1. Submitting CBI. Do not submit this information to EPA through or e-mail. Clearly mark the part or all of the information that you claim to be CBI. For CBI information in a disk or CD ROM that you mail to EPA, mark the outside of the disk or CD ROM as CBI and then identify electronically within the disk or CD ROM the specific information that is claimed as CBI. In addition to one complete version of the comment that includes information claimed as CBI, a copy of the comment that does not contain the information claimed as CBI must be submitted for inclusion in the public docket. Information so marked will not be disclosed except in accordance with procedures set forth in 40 CFR part 2. Send or deliver information identified as CBI only to the following address: Roberto Morales, U.S. EPA, Office of Air Quality Planning and Standards, Mail Code C404-02, Research Triangle Park, NC 27711, telephone (919) 541-0880, e-mail at, Attention Docket ID No. OAR-2010-1059.

2. Tips for Preparing Your Comments. When submitting comments, remember to:

  • Identify the docket number and other identifying information (subject heading, Federal Register date and page number).
  • Follow directions. The agency may ask you to respond to specific questions or organize comments by referencing a part or section number in the guidance.
  • Explain why you agree or disagree with EPA's guidance; and suggest alternatives and substitute language that would help to clarify or better explain the points made and positions taken in EPA's guidance document.

II. Background

The purpose of this notice is to solicit public comments on EPA's recently posted draft non-binding guidance titled, “Guidance for 1-Hour SO2 NAAQS SIP Submissions.” This document is available online at​airquality/​sulfurdioxide/​implement.html or within the associated docket, EPA-HQ-OAR-2010-1059.

The draft guidance document is intended to assist state and tribal governments in preparing State Implementation Plan (SIP) submittals under section 110(a)(1) of the Clean Air Act (CAA) to address implementation, maintenance, and enforcement of the 1-hour primary sulfur dioxide (SO2) National Ambient Quality Standards (NAAQS). The CAA directs states to submit these SIPs to EPA by no later than June 3, 2013, which is 3 years after promulgation of the primary SO2 NAAQS. To be approved, the EPA would expect the SIP submittals to demonstrate through the use of refined air quality dispersion modeling that the affected areas will attain the standard as expeditiously as practicable. This draft guidance provides the basic information that states, tribes and emission sources would need to address the section 110(a)(1) SIP submittal for the 1-hour SO2 NAAQS including modeling guidance. After receiving timely submitted public comments on the draft guidance, the EPA plans to issue updated non-binding guidance. In addition, the EPA will continue to work closely with states and tribes to address issues arising under the section 110(a)(1) SIP submittals.

EPA invites public comment on all aspects of this draft guidance during the 30-day comment period. The draft guidance is not a regulation or any other kind of final action and does not establish binding requirements on the EPA or any state, local, or tribal agency or any emissions source. While the EPA has established a docket and is requesting public comment on the draft guidance, this procedure does not alter the nature or effect of the draft guidance and does not constitute a formal rulemaking process or require the EPA to respond to public comments in the updated guidance before the EPA or other agencies may use the guidance in reaching decisions related to SIPs submitted under section 110(a)(1). The EPA retains the discretion to revise its guidance, issue additional guidance, propose regulations as appropriate, and to utilize information submitted in public comments to inform future decisions. Because this draft guidance does not constitute a formal rulemaking action, the EPA is not required to respond to comments, but intends to take significant comments under consideration in amending or updating Start Printed Page 61100the non-binding guidance. To the extent that the EPA determines that comments received during the 30-day comment period justify corrections or clarifications to the guidance, the EPA may revise and reissue the guidance and post the revised document at:​airquality/​sulfurdioxide/​implement.html.

Please refer to the ADDRESSES section above in this document for specific instructions on submitting comments.

III. Internet Web Site for Guidance Information

The guidance titled, “Guidance for 1-Hour SO2 NAAQS SIP Submissions” can be found at:​airquality/​sulfurdioxide/​implement.html.

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Dated: September 21, 2011.

Mary Henigin,

Acting Director, Office of Air Quality Planning and Standards.

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[FR Doc. 2011-25400 Filed 9-30-11; 8:45 am]