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[Federal Register Volume 89, Number 9 (Friday, January 12, 2024)]
[Notices]
[Page 2223]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-00168]

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ENVIRONMENTAL PROTECTION AGENCY

[EPA-HQ-OAR-2014-0128; FRL-5788-04-OAR]

Release of Policy Assessment for the Review of the Secondary 
National Ambient Air Quality Standards for Oxides of Nitrogen, Oxides 
of Sulfur and Particulate Matter

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of availability.

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SUMMARY: On or about January 12, 2024, the Environmental Protection 
Agency (EPA) will make available the document, Policy Assessment for 
the Review of the Secondary National Ambient Air Quality Standards for 
Oxides of Nitrogen, Oxides of Sulfur and Particulate Matter (PA, EPA-
452/R-24-003). This document was prepared as part of the current review 
of the secondary national ambient air quality standards (NAAQS) for 
Oxides of Nitrogen (NOX), Oxides of Sulfur (SOX), 
and Particulate Matter (PM). The PA serves to ``bridge the gap'' 
between the currently available scientific and technical information 
and the judgments required of the Administrator in determining whether 
to retain or revise the existing secondary NO2, 
SO2 and PM NAAQS. The secondary NAAQS for oxides of 
nitrogen, oxides of sulfur, and particulate matter are set to protect 
the public welfare from known or anticipated effects of these 
pollutants in the ambient air.

DATES: This document will be available on or about January 12, 2024.

ADDRESSES: This document will be available on the EPA's website at 
https://www.epa.gov/naaqs/nitrogen-dioxide-no2-and-sulfur-dioxide-so2-secondary-air-quality-standards. The document will be accessible under 
``Policy Assessments'' from the current review.

FOR FURTHER INFORMATION CONTACT: Ginger Tennant, Office of Air Quality 
Planning and Standards, (Mail Code C504-06), U.S. Environmental 
Protection Agency, P.O. Box 12055, Research Triangle Park, NC 27711; 
telephone number: 919-541-4072, or email: [email protected].

SUPPLEMENTARY INFORMATION: Two sections of the Clean Air Act (CAA or 
the Act) govern the establishment and revision of the NAAQS. Section 
108 directs the Administrator to identify and list certain air 
pollutants and then issue ``air quality criteria'' for those 
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 such pollutant in the ambient air . . .'' 
(CAA section 108(a)(2)). Under section 109 of the Act, the EPA is then 
to establish primary (health-based) and secondary (welfare-based) NAAQS 
for each pollutant for which the EPA has issued air quality criteria. 
Section 109(d)(1) of the Act requires periodic review and, if 
appropriate, revision of existing air quality criteria. Revised air 
quality criteria are to reflect advances in scientific knowledge on the 
effects of the pollutant on public health and welfare. Under the same 
provision, the EPA is also to periodically review and, if appropriate, 
revise the NAAQS, based on the revised air quality criteria.
    The Act additionally requires appointment of an independent 
scientific review committee that is to periodically review the existing 
air quality criteria and NAAQS and to recommend any new standards and 
revisions of existing criteria and standards as may be appropriate (CAA 
section 109(d)(2)(A)-(B)). Since the early 1980s, the requirement for 
an independent scientific review committee has been fulfilled by the 
Clean Air Scientific Advisory Committee (CASAC).
    The EPA's overall plan for this review is presented in the 
Integrated Review Plan for the Secondary National Ambient Air Quality 
Standards for Ecological Effects of Oxides of Nitrogen, Oxides of 
Sulfur and Particulate Matter (IRP).\1\ As described in the IRP, the 
EPA has prepared the Integrated Science Assessment (ISA) for Oxides of 
Nitrogen, Oxides of Sulfur and Particulate Matter Ecological Criteria 
(U.S. EPA, 2020), drafts of which were released in March 2017 and June 
2018 for public comment and review by the CASAC.\2\ A draft of the PA 
was also reviewed by the CASAC (88 FR 17572, March 23, 2023; 88 FR 
45414, July 17, 2023). The final PA reflects consideration of the 
advice and comments from the CASAC on the draft PA, as well as public 
comments. The PA serves to ``bridge the gap'' between the scientific 
and technical information in the 2020 ISA and any air quality, 
exposure, and risk analyses available in this review, and the judgments 
required of the Administrator in determining whether to retain or 
revise the existing secondary ambient air quality standards for 
NO2, SO2 and PM. The final PA document will be 
available on EPA's website at https://www.epa.gov/naaqs/nitrogen-dioxideno2-and-sulfur-dioxide-so2-secondaryair-quality-standards. The 
document briefly described here does not represent and should not be 
construed to represent any final EPA policy, viewpoint, or 
determination.
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    \1\ The IRP is available at https://www.epa.gov/naaqs/nitrogen-dioxide-no2-and-sulfur-dioxide-so2-secondary-standards-planning-documents-current.
    \2\ The ISA is available at: https://www.epa.gov/naaqs/nitrogen-dioxide-no2-and-sulfur-dioxide-so2-secondary-air-quality-standards-
integrated.

    Dated: January 3, 2024.
Erika N. Sasser,
Director, Health and Environmental Impacts Division.
[FR Doc. 2024-00168 Filed 1-11-24; 8:45 am]
BILLING CODE 6560-50-P
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