[Federal Register Volume 84, Number 156 (Tuesday, August 13, 2019)]
[Notices]
[Pages 40044-40047]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-17305]


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ENVIRONMENTAL PROTECTION AGENCY

[EPA-HQ-OAR-2019-0454; FRL-9997-87-OAR]


Conference on Air Quality Modeling

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of conference.

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SUMMARY: The Environmental Protection Agency (EPA) announces its 
Twelfth Conference on Air Quality Modeling. Such a conference is 
required by section 320 of the Clean Air Act (CAA) to be held every 3 
years. The purposes of the Twelfth Conference are to provide an 
overview of the latest features of the currently preferred air quality 
models and to provide a forum for public review and comment on 
potential revisions to the way the Agency determines and applies the 
appropriate air quality models in the future.

DATES: 
    Comments: Comments on potential revisions to the way the Agency 
determines and applies the appropriate air quality models must be 
received on or before November 4, 2019.
    Conference: The conference will be held on October 2 through 3, 
2019, from 8:30 a.m. to 5:00 p.m. Requests to speak at the conference 
should be submitted to the individual listed below in the FOR FURTHER 
INFORMATION CONTACT section by September 13, 2019.

ADDRESSES: 
    Comments: Submit your comments, identified by Docket ID No. EPA-HQ-
OAR-2019-0454 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.

[[Page 40045]]

     Email: Comments may be sent by electronic mail (email) to 
a-and-r-docket@epa.gov, Attention Docket ID No. EPA-HQ-OAR-2019-0454.
     Fax: Fax your comments to (202) 566-9744, Attention Docket 
ID No. EPA-HQ-OAR-2019-0454.
     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-2019-0454.
     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-
2019-0454. 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 website 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, 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.

FOR FURTHER INFORMATION CONTACT: George Bridgers, 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: bridgers.george@epa.gov.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Written Comments

    Submit your comments, identified by Docket ID No. EPA-HQ-OAR-2019-
0454, at https://www.regulations.gov (our preferred method), or the 
other methods identified in the ADDRESSES section. Once submitted, 
comments cannot be edited or removed from the docket. The EPA may 
publish any comment received to its public docket. Do not submit 
electronically any information you consider to be Confidential Business 
Information (CBI) or other information whose disclosure is restricted 
by statute. Multimedia submissions (audio, video, etc.) must be 
accompanied by a written comment. The written comment is considered the 
official comment and should include discussion of all points you wish 
to make. The EPA will generally not consider comments or comment 
contents located outside of the primary submission (i.e., on the Web, 
cloud, or other file sharing system). For additional submission 
methods, the full EPA public comment policy, information about CBI or 
multimedia submissions, and general guidance on making effective 
comments, please visit https://www.epa.gov/dockets/commenting-epa-dockets.
    Submitting CBI: 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 marked as CBI 
will not be disclosed except in accordance with procedures set forth in 
Title 40 Code of Federal Regulations (CFR) part 2.
    Do not submit information that you consider to be CBI or otherwise 
protected through http://www.regulations.gov or email. Send or deliver 
information identified as CBI to only the following address: OAQPS 
Document Control Officer (Room C404-02), U.S. EPA, Research Triangle 
Park, NC 27711, Attention Docket ID No. EPA-HQ-OAR-2019-0454.
    If you have any questions about CBI or the procedures for claiming 
CBI, please consult the person identified in the FOR FURTHER 
INFORMATION CONTACT section.
    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 (Confidential Business 
Information) 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 http://www.regulations.gov or in hard copy at the EPA Docket Center, EPA/DC, 
EPA WJC West Building, Room 3334, 1301 Constitution Ave. NW, 
Washington, DC. This Docket Facility 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.

B. Background Information

    Additional information and a more detailed agenda are 
electronically available at https://www.epa.gov/scram/12th-conference-air-quality-modeling.

C. Conference

    The conference will be held in the EPA Auditorium, Room C111, 109 
T.W. Alexander Drive, Research Triangle Park, NC 27711.

II. Background

    The Guideline on Air Quality Models (Guideline), which is found in 
Appendix W to 40 CFR (Code of Federal

[[Page 40046]]

Regulations) part 51, is used by the EPA, other federal, state, 
territorial, local, and tribal air quality agencies, and industry to 
prepare and review new or modified source permits, State Implementation 
Plan (SIP) submittals or revisions, conformity, and other air quality 
assessments required under the CAA and EPA regulations. The Guideline 
serves as a means by which national consistency is maintained in air 
quality analyses for regulatory activities under 40 CFR 51.112, 51.117, 
51.150, 51.160, 51.165, 51.166, 52.21, 93.116, 93.123, and 93.150.
    The EPA originally published the Guideline in April 1978 (EPA-450/
2-78-027), and it was incorporated by reference in the regulations for 
the PSD program in June 1978. The EPA revised the Guideline in 1986 (51 
FR 32176), and updated it with supplement A in 1987 (53 FR 32081), 
supplement B in July 1993 (58 FR 38816), and supplement C in August 
1995 (60 FR 40465). The EPA published the Guideline as appendix W to 40 
CFR part 51 when the EPA issued supplement B. The EPA republished the 
Guideline in August 1996 (61 FR 41838) to adopt the CFR system for 
labeling paragraphs. Subsequently, the EPA revised the Guideline on 
April 15, 2003 (68 FR 18440), to adopt CALPUFF as the preferred model 
for long-range transport of emissions from 50 to several hundred 
kilometers (km) and to make various editorial changes to update and 
reorganize information and remove obsolete models. The EPA further 
revised the Guideline on November 9, 2005 (70 FR 68218), to adopt 
AERMOD as the preferred model for near-field dispersion of emissions 
for distances up to 50 km. The publication and incorporation of the 
Guideline into the EPA's Prevention of Significant Deterioration (PSD) 
regulations satisfies the requirement under CAA section 165(e)(3) for 
the EPA to promulgate regulations that specify, with reasonable 
particularity, models to be used under specified sets of conditions for 
purposes of the PSD program.
    On July 29, 2015, the EPA proposed the revisions to the Guideline 
in the Federal Register (80 FR 45340). To inform the development of 
these proposed revisions to the Guideline and in compliance with CAA 
section 320, the EPA held the Tenth Conference on Air Quality Modeling 
in March 2012. The conference addressed updates on (1) the regulatory 
status and future development of AERMOD and CALPUFF; (2) review of the 
Mesoscale Model Interface (MMIF) prognostic meteorological data 
processing tool for dispersion models; (3) draft modeling guidance for 
compliance demonstrations of the fine particulate matter 
(PM2.5) National Ambient Air Quality Standards (NAAQS); (4) 
modeling for compliance demonstration of the 1-hour nitrogen dioxide 
(NO2) and sulfur dioxide (SO2) NAAQS; and (5) new 
and emerging models/techniques for future consideration under the 
Guideline to address single-source modeling for ozone and secondary 
PM2.5, as well as long-range transport and chemistry. Based 
on comments received from stakeholders at the Tenth Modeling 
Conference, ``Phase 3'' of the Interagency Workgroup on Air Quality 
Modeling (IWAQM) was formalized in June 2013 to provide additional 
guidance for modeling single-source impacts on secondarily formed 
pollutants (e.g., ozone and PM2.5) in the near-field and for 
long-range transport. A transcript of the conference proceedings and a 
summary of the public comments received are available in the docket for 
the Tenth Modeling Conference (Docket ID No. EPA-HQ-OAR-2012-0056). 
Additionally, all of the materials associated with this conference are 
available on the EPA's SCRAM website at https://www3.epa.gov/ttn/scram/10thmodconf.htm.
    The Eleventh Conference on Air Quality Modeling was held August 12-
13, 2015, in continuing compliance with CAA section 320. This 
conference included the public hearing for the proposed revisions to 
the Guideline. It began with a thorough overview of these proposed 
revisions, including presentations from EPA staff on the formulation 
updates to the preferred models and the research and technical 
evaluations that support these and other revisions. Specifically, there 
were presentations summarizing the proposed updates to the AERMOD 
modeling system; replacement of CALINE3 with AERMOD for modeling of 
mobile sources; incorporation of prognostic meteorological data for use 
in dispersion modeling; the proposed screening approach for long-range 
transport for NAAQS and PSD increments assessments with use of CALPUFF 
as a screening technique rather than an EPA-preferred model; the 
proposed 2-tiered screening approach to address ozone and 
PM2.5 in PSD compliance demonstrations; the status and role 
of the Model Clearinghouse; and updates to procedures for single-source 
and cumulative modeling analyses (e.g., modeling domain, source input 
data, background data, and compliance demonstration procedures). At the 
conclusion of these presentations, the public hearing on the proposed 
revisions to the Guideline was convened. The EPA presentations and the 
presentations from the public hearing, along with the transcript of the 
conference proceedings, are available in the docket for the Eleventh 
Modeling Conference (Docket ID No. EPA-HQ-OAR-2015-0310). Additionally, 
all of the materials associated with the Eleventh Modeling Conference 
and the public hearing are available on the EPA's SCRAM website at 
https://www3.epa.gov/ttn/scram/11thmodconf.htm.
    The 2015 proposed revisions to the Guideline were finalized and 
published in the Federal Register (82 FR 5182) on January 17, 2017. 
Supporting information on this final rule is available on the EPA's 
SCRAM website at https://www3.epa.gov/ttn/scram/appendix_w-2016.htm and 
a direct link to the final rule publication is https://www3.epa.gov/ttn/scram/guidance/guide/appw_17.pdf.

III. Public Participation

    The Twelfth 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:
    1. Conference overview;
    2. Currently preferred air quality models status and updates;
    3. Expert panel discussions and invited presentations on model/
technique enhancements:

 Treatment of low wind conditions
 Building downwash
 Mobile source modeling
 Overwater modeling
 Prognostic meteorological data
 Near-field and long-range model evaluation criteria
 NO2 modeling techniques
 Single source O3 and PM2.5 modeling 
techniques
 Plume rise;

    4. Model Clearinghouse and modeling guidance updates; and
    5. 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 us 
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

[[Page 40047]]

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-2019-0454, which will remain 
open until November 4, 2019, for the purpose of receiving additional 
comments.

    Dated: August 2, 2019.
Panagiotis E. Tsirigotis,
Director, Office of Air Quality Planning and Standards.
[FR Doc. 2019-17305 Filed 8-12-19; 8:45 am]
 BILLING CODE 6560-50-P


