Release of the Policy Assessment for the Reconsideration of the National Ambient Air Quality Standards for Particulate Matter

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Notice of availability; policy assessment.

SUMMARY:

On or about May 23, 2022, the Environmental Protection Agency (EPA) will make available the document, Policy Assessment for the Reconsideration of the National Ambient Air Quality Standards for Particulate Matter (PA). This document was prepared as a part of the current reconsideration of the 2020 final decision on the National Ambient Air Quality Standards (NAAQS) for 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 PM NAAQS.

DATES:

This document will be available on or about May 23, 2022.

ADDRESSES:

This document will be available on the EPA's website at https://www.epa.gov/naaqs/particulate-matter-pm-air-quality-standards. The document will be accessible under “Policy Assessments” from the current review.

FOR FURTHER INFORMATION CONTACT:

Dr. Lars Perlmutt, Office of Air Quality Planning and Standards, (Mail Code C539-04), U.S. Environmental Protection Agency, Research Triangle Park, NC 27711; telephone number: 919-541-3037, fax number: 919-541-5315; or email: perlmutt.lars@epa.gov.

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). In December 2020, the EPA announced its final decision to retain the primary and secondary PM_2.5 and PM₁₀ standards, without revision (85 FR 82684, December 18, 2020). On June 10, 2021, the Agency announced its decision to reconsider the 2020 p.m. NAAQS final action. In its announcement of the reconsideration of the PM NAAQS, the Agency explained that, in support of the reconsideration, it would develop a supplement to the 2019 Integrated Science Assessment (ISA Supplement) and an updated PA. A draft of the ISA Supplement was released in September 2021 (86 FR 54186, September 30, 2021) and a draft of the PA was released in October 2021 (86 FR 56263, October 8, 2021). The draft ISA Supplement and the draft PA were reviewed by the seven-member chartered CASAC, with support from the PM CASAC Panel. The final PA reflects consideration of the advice and comments from the CASAC, as well as public comments, on the draft PA. The PA serves to “bridge the gap” between the scientific and technical information in the 2019 ISA and ISA Supplement and any air quality, exposure and risk analyses available in the reconsideration, and the judgments required of the Administrator in determining whether to retain or revise the existing PM NAAQS. The PA builds upon the information presented in the 2019 ISA, the ISA Supplement, and the 2020 PA. The PA document will be available on or about May 23, 2022, on the EPA's website at https://www.epa.gov/naaqs/particulate-matter-pm-air-quality-standards.

The document briefly described above does not represent and should not be construed to represent any final EPA policy, viewpoint, or determination.