2020-11121. Release of Policy Assessment for the Ozone National Ambient Air Quality Standards

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Notice of availability.

SUMMARY:

On or about May 29, 2020, the Environmental Protection Agency (EPA) will make available the document, Policy Assessment for the Ozone National Ambient Air Quality Standards (PA, EPA-452/R-20-001). This document was prepared as part of the current review of the national ambient air quality standards (NAAQS) for photochemical oxidants including ozone (O₃). 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 O₃ NAAQS. The primary and secondary O₃ NAAQS are set to protect the public health and the public welfare from O₃ and other photochemical oxidants in ambient air.

DATES:

This document will be available on or about May 29, 2020.

ADDRESSES:

This document will be available on the EPA's website at https://www.epa.gov/​naaqs/​ozone-o3-air-quality-standards. The document will be accessible under “Policy Assessments” from the current review.

FOR FURTHER INFORMATION CONTACT:

Dr. Deirdre L. Murphy, Office of Air Quality Planning and Standards, (Mail Code C504-06), U.S. Environmental Protection Agency, Research Triangle Park, NC 27711; telephone number: 919-541-0729, fax number: 919-541-0237; or email: [e-mail].

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).

Presently the EPA is reviewing the air quality criteria and NAAQS for photochemical oxidants and O₃.^[1] The EPA's overall plan for this review is presented in the Integrated Review Plan for the Ozone NAAQS (IRP).^[2] As described in the IRP, the EPA has prepared an Integrated Science Assessment for Ozone and Related Photochemical Oxidants (ISA), a draft of which was released in September 2019 for public comment and review by the CASAC.^[3] A draft of the PA was also reviewed by the CASAC (84 FR 58713, November 1, 2019; 85 FR 4656, January 27, 2020). The final PA reflects consideration of the advice and comments from the CASAC,^[4] as well as public comments, on the draft PA. The PA serves to “bridge the gap” between the scientific and technical information in the final ISA and any air quality, exposure and risk analyses available in the review, and the judgments required of the Administrator in determining whether to retain or revise the existing ozone NAAQS. The PA builds upon information presented in the ISA and quantitative air quality, exposure and risk analyses (presented in appendices to the PA). The PA document will be available on or about May 29, 2020, on the EPA's website at https://www.epa.gov/​naaqs/​ozone-o3-air-quality-standards. The document briefly described here does not represent and should not be construed to represent any final EPA policy, viewpoint, or determination.

Dated: May 19, 2020.

Panagiotis Tsirigotis,

Director, Office of Air Quality Planning and Standards.

Footnotes

1.  The EPA's call for information for this review was issued on June 26, 2018 (83 FR 29785).

2.  The IRP is available at https://www.epa.gov/​naaqs/​ozone-o3-standards-planning-documents-current-review.

3.  The ISA is available at: https://www.epa.gov/​naaqs/​ozone-o3-standards-integrated-science-assessments-current-review.

4.  The CASAC comments are available at: https://yosemite.epa.gov/​sab/​sabproduct.nsf/​WebProjectsbyTopicCASAC!OpenView.