[Federal Register Volume 83, Number 94 (Tuesday, May 15, 2018)]
[Notices]
[Page 22479]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-10242]


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ENVIRONMENTAL PROTECTION AGENCY

[EPA-HQ-OAR-2013-0566; FRL-9977-81-OAR]


Release of Final Documents Related to the Review of the Primary 
National Ambient Air Quality Standards for Sulfur Oxides

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of availability.

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SUMMARY: The Environmental Protection Agency (EPA) is announcing the 
availability of two final documents titled, Risk and Exposure 
Assessment for the Review of the Primary National Ambient Air Quality 
Standard for Sulfur Oxides (REA) and Policy Assessment for the Review 
of the Primary National Ambient Air Quality Standard for Sulfur Oxides 
(PA). The indicator for the current standard is sulfur dioxide 
(SO2). The REA describes the quantitative analyses of 
SO2 exposures and health risks in this NAAQS review. 
Building on the Integrated Science Assessment for Sulfur Oxides--Health 
Criteria (ISA), completed in December 2017, the PA serves to ``bridge 
the gap'' between the scientific information and the judgments required 
of the Administrator in determining whether to retain or revise the 
existing primary NAAQS for SO2.

DATES: The REA and PA will be made available on or about May 9, 2018.

ADDRESSES: These documents will be available primarily via the internet 
at https://www.epa.gov/naaqs/sulfur-dioxide-so2-primary-air-quality-standards.

FOR FURTHER INFORMATION CONTACT: Dr. Nicole Hagan, Office of Air 
Quality Planning and Standards (Mail Code C504-06), U.S. Environmental 
Protection Agency, Research Triangle Park, NC 27711; telephone number: 
919-541-3153; fax number: 919-541-5315; email: [email protected].

SUPPLEMENTARY INFORMATION: Two sections of the Clean Air Act govern the 
establishment and revision of the NAAQS. Section 108 (42 U.S.C. 7408) 
directs the Administrator to identify and list certain air pollutants 
and then to issue air quality criteria for those pollutants. The 
Administrator is to list those air pollutants that in his ``judgment, 
cause or contribute to air pollution which may reasonably be 
anticipated to endanger public health or welfare''; ``the presence of 
which in the ambient air results from numerous or diverse mobile or 
stationary sources''; and ``for which . . . [the Administrator] plans 
to issue air quality criteria . . .'' (42 U.S.C. 7408(a)(1)(A)(C)). Air 
quality criteria are intended 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 . . .'' (42 
U.S.C. 7408(a)(2)). Under section 109 (42 U.S.C. 7409), the EPA 
establishes primary (health-based) and secondary (welfare-based) NAAQS 
for pollutants for which air quality criteria are issued. Section 
109(d) 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. Section 109(d)(2) requires that an independent scientific 
review committee ``shall complete a review of the criteria . . . and 
the national primary and secondary ambient air quality standards . . . 
and shall recommend to the Administrator any new . . . standards and 
revisions of the existing criteria and standards as may be appropriate 
. . . .'' Since the early 1980s, this independent review function has 
been performed by the Clean Air Scientific Advisory Committee (CASAC).
    The current periodic review of the air quality criteria and primary 
NAAQS for SOX began in 2013. The final ISA, prepared for 
this review by the EPA's Office of Research and Development, was made 
available in December 2017 (82 FR 58600).\1\ The REA and PA build upon 
information presented in the ISA. Drafts of the REA and PA were 
reviewed by the CASAC SOX Panel at a public meeting held on 
September 18-19, 2017, and a teleconference on April 20, 2018, and were 
made available for public comment. The CASAC's advice on the draft 
documents were provided in letters to the EPA Administrator dated April 
30, 2018.\2\ The final versions of the REA and PA reflect staff's 
consideration of the advice and comments from CASAC, as well as public 
comments. The final REA and PA are available at https://www.epa.gov/naaqs/sulfur-dioxide-so2-primary-air-quality-standards.
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    \1\ The final ISA is available at: https://www.epa.gov/naaqs/sulfur-dioxide-so2-primary-standards-integrated-science-assessments-current-review.
    \2\ The CASAC letters are available at: https://
yosemite.epa.gov/sab/sabproduct.nsf/
264cb1227d55e02c85257402007446a4/0125714DA9A892238525827F00751B99/
$File/EPA-CASAC-18-001.pdf and https://yosemite.epa.gov/sab/
sabproduct.nsf/264cb1227d55e02c85257402007446a4/
23631E258D63BDEB8525827F0075335E/$File/EPA-CASAC-18-002.pdf.

    Dated: May 8, 2018.
Panagiotis Tsirigotis,
Director, Office of Air Quality Planning and Standards.
[FR Doc. 2018-10242 Filed 5-14-18; 8:45 am]
 BILLING CODE 6560-50-P