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[Federal Register Volume 73, Number 169 (Friday, August 29, 2008)]
[Notices]
[Pages 50965-50967]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E8-20136]

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ENVIRONMENTAL PROTECTION AGENCY

[EPA-HQ-OAR-2007-1145; FRL-8709-3]

Draft Risk and Exposure Assessment Report for Review of the 
Secondary National Ambient Air Quality Standards for Oxides of Nitrogen 
and Oxides of Sulfur

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of draft report for public review and comment.

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SUMMARY: On or about August 27, 2008, the Office of Air Quality 
Planning and Standards (OAQPS) of EPA is making available for public 
review and comment a draft document titled ``Risk and Exposure 
Assessment to Support the Review of the Secondary National Ambient Air 
Quality Standards for Oxides of Nitrogen and Oxides of Sulfur: First 
Draft.'' The purpose of this draft document is to convey the approach 
EPA has taken to assess environmental exposures to ambient oxides of 
nitrogen and sulfur and to characterize associated public welfare 
risks, as well as to present the results of those assessments. We 
anticipate the release of an additional chapter(s) on or about the week 
of September 15, 2008.

DATES: Comments on the above report must be received on or before 
October 15, 2008.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-
OAR-2007-1145, by one of the following methods:
    http://www.regulations.gov: Follow the on-line 
instructions for submitting comments.
     E-mail: Comments may be sent by electronic mail (e-mail) 
to [email protected], Attention Docket ID No. EPA-HQ-OAR-2007-
1145.
     Fax: Fax your comments to 202-566-9744, Attention Docket 
ID. No. EPA-HQ-OAR-2007-1145.
     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-2007-1145.
     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-
2007-1145. 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 e-mail. The http://www.regulations.gov 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

[[Page 50966]]

to EPA without going through http://www.regulations.gov 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 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. 
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: Dr. Anne Rea, Office of Air Quality 
Planning and Standards (Mailcode C539-02), U.S. Environmental 
Protection Agency, Research Triangle Park, NC 27711; e-mail: 
[email protected]; telephone: 919-541-0053; fax: 919-541-0840.

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 
http://www.regulations.gov 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.
    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 
reproduced.
     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.

SUPPLEMENTARY INFORMATION: Under section 108(a) of the Clean Air Act 
(CAA), the Administrator identifies and lists certain pollutants which 
``cause or contribute to air pollution which may reasonably be 
anticipated to endanger public health or welfare.'' The EPA then issues 
air quality criteria for listed pollutants, which are commonly referred 
to as ``criteria pollutants.'' The 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, in varying quantities.'' Under section 
109 of the CAA, EPA establishes NAAQS for each listed pollutant, with 
the NAAQS based on the air quality criteria. Section 109(d) of the CAA 
requires periodic review and, if appropriate, revision of existing air 
quality criteria. The revised air quality criteria reflect advances in 
scientific knowledge on the effects of the pollutant on public health 
or welfare. The EPA is also required to periodically review and revise 
the NAAQS, if appropriate, based on the revised criteria.
    EPA is currently conducting a joint review of the existing 
secondary (welfare-based) national ambient air quality standards 
(NAAQS) for nitrogen dioxide (NO2) and sulfur dioxide 
(SO2). Because NOX, SOX, and their 
associated transformation products are linked from an atmospheric 
chemistry perspective as well as from an environmental effects 
perspective, and because of the National Research Council's (NRC's) 
2004 recommendations to consider multiple pollutants in forming the 
scientific basis for the NAAQS, EPA has decided to jointly assess the 
science, risks, and policies relevant to protecting the public welfare 
associated with oxides of nitrogen and oxides of sulfur. This is the 
first time since NAAQS were established in 1971 that a joint review of 
these two pollutants has been conducted. Since both the Clean Air 
Scientific Advisory Committee (CASAC) and EPA have recognized these 
interactions historically, and the science related to these 
interactions has continued to evolve and grow to the present day, there 
is a strong basis for considering them together.
    As part of its review of the secondary NAAQS for NOX and 
SOX, EPA is preparing an assessment of exposures and 
characterization of risks for adverse ecological effects associated 
with atmospheric NOX and SOX deposition. A draft 
plan describing the proposed approaches to assessing ecological 
exposures and effects is described in the draft document, Draft Scope 
and Methods Plan for Risk/Exposure Assessment: Secondary NAAQS Review 
for Oxides of Nitrogen and Oxides of Sulfur. This document was released 
for public review and comment in March, 2008 and was the subject of a 
consultation with the CASAC on April 2 and 3, 2008. Comments received 
from that consultation have been considered in developing the first 
draft risk and exposure assessment for the secondary NOX/
SOX NAAQS review being released at this time.
    The first draft risk and exposure assessment for the secondary 
NOX/SOX NAAQS review released at this time 
conveys our approach to assess ecological effects due to the deposition 
of ambient NOX and SOX, and present the results 
of these analyses. This draft document will be available online at: 
http://www.epa.gov/ttn/naaqs/standards/no2so2sec/cr_rea.html.
    The EPA is soliciting advice and recommendations from the CASAC by 
means of a review on the draft document at an upcoming public meeting 
of the CASAC scheduled for October 1-2, 2008 in Research Triangle Park, 
N.C. Following the CASAC

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meeting, EPA will consider comments received from the CASAC and the 
public in preparing a second draft risk and exposure assessment report. 
The release of the second draft report will be followed by another 
CASAC meeting which will be announced in a future Federal Register 
notice and ultimately EPA will release a final risk and exposure 
assessment document taking into consideration comments from the CASAC 
and public.

    Dated: August 21, 2008.
Jennifer N. Edmonds,
Acting Director, Office of Air Quality Planning and Standards.
[FR Doc. E8-20136 Filed 8-28-08; 8:45 am]
BILLING CODE 6560-50-P
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