[Federal Register Volume 77, Number 20 (Tuesday, January 31, 2012)]
[Pages 4808-4810]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2012-2026]



[EPA-HQ-OAR-2012-0056; FRL-9625-1]

Conference on Air Quality Modeling

AGENCY: U.S. Environmental Protection Agency (EPA).

ACTION: Notice of conference.


SUMMARY: The EPA will be hosting the Tenth Conference on Air Quality 
Modeling on March 13-15, 2012. Section 320 of the Clean Air Act (CAA) 
requires a conference to be held every 3 years. The purpose of the 
conference is to provide an overview of the latest features of the 
agency's preferred air quality models and to provide a forum for public 
review and comment on how the agency determines and applies air quality 
models in the future.

DATES: Comments: Comments on how the agency determines and applies air 
quality models must be received on or before April 16, 2012.
    Conference: The conference will be held on March 13 through 15, 
2012, from 8:30 a.m. to 5:00 p.m. Requests to speak at the conference 
should be submitted to the individual listed below by March 5, 2012.

ADDRESSES: Comments: Submit your comments, identified by Docket ID No. 
EPA-HQ-OAR-2012-0056 by one of the following methods:
     http://www.regulations.gov: Follow the on-line 
instructions for submitting comments. This is the EPA's preferred 
method for receiving comments.
     Email: Comments may be sent by electronic mail (email) to 
[email protected], Attention Docket ID No. EPA-HQ-OAR-2012-0056.
     Fax: Fax your comments to (202) 566-9744, Attention Docket 
ID No. EPA-HQ-OAR-2012-0056.
     Mail: Send your comments to: Air and Radiation Docket and 
Information Center, Environmental Protection Agency, Mailcode: 2822T, 
1200 Pennsylvania Ave. NW., Washington, DC 20460, Attention Docket ID 
No. EPA-HQ-OAR-2012-0056.
     Hand Delivery or Courier: Deliver your comments to EPA 
Docket Center, 1301 Constitution Ave. NW., Room 3334, Washington, DC. 
Such deliveries are only accepted during the Docket'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-
2012-0056. 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 http://www.regulations.gov, 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 http://www.regulations.gov or email. The http://www.regulations.gov Web site 
is an ``anonymous access'' system, which means the EPA will not know 
your identity or contact information unless you provide it in the body 
of your comment. If you send an email comment directly to the EPA 
without going through http://www.regulations.gov, your email 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, the 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 the EPA cannot read your comment 
due to technical difficulties and cannot contact you for clarification, 
the 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 the 
EPA's public docket, visit the EPA Docket Center homepage at http://www.epa.gov/epahome/dockets.htm.
    Docket: All documents in the docket are listed in the http://www.regulations.gov 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 
form. Publicly available docket materials are available either 
electronically in http://www.regulations.gov or in hard copy at the Air 
Docket in the EPA Docket Center, EPA West, Room 3334, 1301 Constitution 
Ave. NW., Washington,

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DC. This docket facility is open from 8:30 a.m. to 4:30 p.m., Monday 
through Friday, excluding legal holidays. The Docket telephone number 
is (202) 566-1742; fax (202) 566-9744.
    Background Information: Additional information and a more detailed 
agenda are electronically available at http://www.epa.gov/ttn/scram/10thmodconf.htm.
    Conference: The conference will be held in the EPA Auditorium, Room 
C111, 109 T.W. Alexander Drive, Research Triangle Park, NC 27711.

FOR FURTHER INFORMATION CONTACT: George Bridgers, U.S. Environmental 
Protection Agency, Office of Air Quality Planning and Standards, Air 
Quality Assessment Division, Mail Code C439-01, Research Triangle Park, 
NC 27711; telephone: (919) 541-5563; fax: (919) 541-0044; email 
address: [email protected].


I. General Information

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

    1. Submitting CBI. Do not submit this information to the EPA 
through www.regulations.gov or email. 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 the 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.
    2. Tips for Preparing Your Comments. When submitting comments, 
remember to:
     Identify the rulemaking by 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 Code of 
Federal Regulations (CFR) part or section number.
     Explain why you agree or disagree; suggest alternatives 
and substitute language for your requested changes.
     Describe any assumptions and provide any technical 
information and/or data that you used.
     If you estimate potential costs or burdens, explain how 
you arrived at your estimate in sufficient detail to allow for it to be 
     Provide specific examples to illustrate your concerns, and 
suggest alternatives.
     Explain your views as clearly as possible, avoiding the 
use of profanity or personal threats.
     Make sure to submit your comments by the comment period 
deadline identified.

II. Background

    The Guideline on Air Quality Models (hereafter, called the 
Guideline, which is found in Appendix W to 40 CFR part 51), is used by 
the EPA, states and industry to prepare and review new source permits, 
source permit modifications, and State Implementation Plan submittals 
and revisions. The Guideline serves as a means by which national 
consistency is maintained in air quality analyses. We originally 
published the Guideline in April 1978, and it was incorporated by 
reference in the regulations for the Prevention of Significant 
Deterioration of Air Quality in June 1978. We revised the Guideline in 
1986, and updated it with supplement A in 1987, supplement B in July 
1993, and supplement C in August 1995. We published the Guideline as 
Appendix W to 40 CFR part 51 when we issued supplement B. We 
republished the Guideline in August 1996 (61 FR 41838) to adopt the CFR 
system for labeling paragraphs.
    To support the process of developing and revising the Guideline 
during the period 1977-1988, we held the First, Second, and Third 
Conferences on Air Quality Modeling as required by CAA Section 320 to 
help standardize modeling procedures. These modeling conferences 
provided us with comments on the Guideline and associated revisions, 
thereby helping us introduce improved modeling techniques into the 
regulatory process.
    In October 1988, we held the Fourth Conference on Air Quality 
Modeling to advise the public on new modeling techniques and to solicit 
comments to guide our consideration of any rulemaking needed to further 
revise the Guideline. We held the Fifth Conference in March 1991, which 
served as a public hearing for the proposed revisions to the Guideline. 
In August 1995, we held the Sixth Conference as a forum to update our 
available modeling tools with state-of-the-science techniques and for 
the public to offer new ideas. The Seventh Conference was held in June 
2000 and served as a public hearing for the proposed changes to the 
recommended air quality models in Appendix W including the CALPUFF 
modeling system, AERMOD modeling system, and ISC-PRIME model. We held 
the Eighth Conference on Air Quality Modeling in September 2005, which 
provided details on changes to these recommended air quality models, 
including the Notice of Data Availability published in September 2003 
related to the incorporation of the PRIME downwash algorithm in the 
AERMOD dispersion model in response to comments received from the 
Seventh Conference, and details on available methods for model 
performance evaluation. Additionally, at the Eighth Conference, there 
was a panel of experts discussion on the use of state-of-the-science 
prognostic meteorological data for informing the dispersion models.
    The most recent conference was the Ninth Conference on Air Quality 
Modeling held in October 2008. The conference began with an overview 
presentation and review of Appendix W and plans to reinstitute the 
Model Clearinghouse. Several presentations were made on non-guideline 
applications of dispersion models as well as a continuation of 
discussions from the Eighth Conference on the use of prognostic 
meteorological data with respect to informing the Appendix W models. 
Updates were provided on the regulatory status, recent coding changes, 
and future development of the AERMOD modeling system, the EPA's 
preferred model for near-field regulatory applications, and the CALPUFF 
modeling system, the EPA's preferred model for long-range transport of 
criteria pollutants and their impacts on Federal Class I areas. The 
Ninth Conference concluded with a collection of presentations reviewing 
the available model evaluation methods and reviewing new and emerging 
models and techniques for future consideration under Appendix W. The 
proceedings, including supporting material and public comments 
received, are found in Docket No. EPA-HQ-OAR-2008-0604.

III. Public Participation

    The Tenth Conference on Air Quality Modeling will be open to the 
public; no admission fee is charged and there is no formal 
registration. The conference will begin the first morning with 
introductory remarks by the presiding EPA official. The following 
topics will be presented:
    A. Appendix W overview;
    B. Model Clearinghouse update;
    C. Currently preferred air quality models (AERMOD and CALPUFF) 
status and updates;
    D. Review of prognostic meteorological data processing tool for 
dispersion models, MMIF;

[[Page 4810]]

    E. Modeling for compliance demonstration of the PM2.5 
National Ambient Air Quality Standards (NAAQS) including discussion of 
the draft PM2.5 (primary and secondary) modeling guidance;
    F. Modeling for compliance demonstration of the 1-hour 
NO2 and SO2 NAAQS including presentations from 
the AERMOD Implementation Workgroup NO2 and SO2 
modeling study;
    G. Review of new and emerging models/techniques for future 
consideration under Appendix W to address long-range transport and 
chemistry; and
    H. Other presentations by the public.
    Those wishing to speak at the conference, whether to volunteer a 
presentation on a special topic or to offer general comment on any of 
the modeling techniques scheduled for presentation, should contact the 
EPA at the address given in the FOR FURTHER INFORMATION CONTACT section 
(note the cutoff date). Such persons should identify the organization 
(if any) on whose behalf they are speaking and the length of the 
presentation. If a presentation of general comments is projected to be 
longer than 10 minutes, the presenter should also state why a longer 
period is needed. Persons failing to submit a written notice but 
desiring to speak at the conference should notify the presiding officer 
immediately before the conference, and they will be scheduled on a 
time-available basis.
    The conference will be conducted informally and chaired by an EPA 
official. There will be no sworn testimony or cross examination. A 
verbatim transcript of the conference proceedings will be produced and 
placed in the docket. Speakers should bring extra copies of their 
presentation for inclusion in the docket and for the convenience of the 
recorder. Speakers will also be permitted to enter written comments 
into the record. Additional written statements or comments should be 
sent to the OAR Regulatory Docket (see ADDRESSES section). A transcript 
of the proceedings and a copy of all written comments will be 
maintained in Docket ID No. EPA-HQ-OAR-2012-0056, which will remain 
open until April 16, 2012, for the purpose of receiving additional 

    Dated: January 25, 2012.
Mary E. Henigin,
Acting Director, Office of Air Quality Planning and Standards.
[FR Doc. 2012-2026 Filed 1-30-12; 8:45 am]