2017-07558. Release of the Policy Assessment for the Review of the Primary National Ambient Air Quality Standards for Oxides of Nitrogen

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Notice of availability.

SUMMARY:

The Environmental Protection Agency (EPA) is announcing the availability of the final document titled Policy Assessment for the Review of the Primary National Ambient Air Quality Standards for Oxides of Nitrogen (NO₂PA). Nitrogen dioxide (NO₂) is the component of oxides of nitrogen (NO_X) for which we have the greatest concern for public health. Accordingly, the current primary (health-based) National Ambient Air Quality Standards (NAAQS) for NO_X are in terms of NO_2. The NO₂ PA presents considerations and conclusions relevant for the EPA's review of the primary NO₂ NAAQS. The primary NO₂ NAAQS are set to protect the public health from exposures to NO₂ in ambient air.

DATES:

The NO₂ PA will be available on or about April 12, 2017.

ADDRESSES:

The NO₂ PA will be available primarily via the Internet at: https://www.epa.gov/​naaqs/​nitrogen-dioxide-no2-primary-standards-policy-assessments-current-review.

FOR FURTHER INFORMATION CONTACT:

Ms. Breanna Alman, Office of Air Quality Planning and Standards (Mail Code C504-06), U.S. Environmental Protection Agency, Research Triangle Park, NC 27711; telephone number: 919-541-2351; email: [e-mail].

SUPPLEMENTARY INFORMATION:

Two sections of the Clean Air Act (CAA) 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 . . .” 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(b). 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. 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, if appropriate, revise the NAAQS 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).

Presently, the EPA is reviewing the criteria and the primary NAAQS for NO_X. The EPA released the final Integrated Science Assessment for Oxides of Nitrogen—Health Criteria (the ISA) in January 2016. Drawing from the ISA, a draft NO₂ PA was prepared by the EPA's Office of Air Quality Planning and Standards, within the Office of Air and Radiation. The draft NO₂ PA presented preliminary staff conclusions on the adequacy of the current standards and addressed key policy-relevant science issues that guided the review. The draft NO₂ PA was reviewed by the CASAC at a public meeting on November 9-10, 2016, and a teleconference on January 24, 2017. The CASAC's advice on the draft NO₂ PA was conveyed in a letter to the Administrator dated March 7, 2017.^[1] The final NO₂ PA being released at this time reflects consideration of the CASAC's advice and public comments received on the draft NO₂ PA.

Dated: April 10, 2017.

Stephen Page,

Director, Office of Air Quality Planning and Standards.

Footnotes

1.  Available at: https://yosemite.epa.gov/​sab/​sabproduct.nsf/​LookupWebProjectsCurrentCASAC/​7C2807D0D9BB4CC8852580DD004EBC32/​$File/​EPA-CASAC-17-001.pdf.