Comment submitted by Chris Frey (Part 1 of 3)

Summary of Submitted Comments These comments address the scientific-review process associated with EPA's review of the primary National Ambient Air Quality Standards (NAAQS) for oxides of nitrogen (NO₂), with particular focus on review of the draft Integrated Science Assessment for Oxides of Nitrogen – Health Criteria (ISA). The comments do not evaluate the scientific conclusions of the draft ISA and neither support nor oppose any specific NAAQS decision. Rather, they focus on whether EPA has adequately explained how the scientific-review process for the current NO₂ review will provide the breadth, depth, diversity, continuity, and multidisciplinary deliberation of expertise that EPA itself previously determined were necessary for the review. A central concern is the apparent disappearance of the CASAC NO₂ Review Panel from the current review process. EPA established the panel in January 2024 through a public nomination and appointment process, identified multiple areas of scientific expertise as necessary for the review, convened the panel, and used it during consultation on the Integrated Review Plan. The panel therefore became part of the review structure for the current NO₂ review cycle. However, the panel no longer appears among active CASAC panels, and EPA has not publicly explained whether the panel has been terminated, placed in inactive status, suspended, or otherwise removed from participation in the review. EPA also has not publicly explained how the scientific-review functions previously provided by the panel will be performed during review of the draft ISA and subsequent review products. The attached comments examine this issue from multiple perspectives, including EPA's own expertise determinations, historical use of pollutant-specific CASAC review panels, federal peer-review principles, National Academies recommendations regarding causal determinations, multidisciplinary scientific deliberation, the Clean Air Act, FACA, IQA, ERDDAA, and administrative-record considerations. The principal findings are: EPA determined in 2024 that multidisciplinary expertise was necessary for the current review. The NO₂ Review Panel became part of the review structure for the current review cycle. EPA has not publicly explained the status of the panel. EPA has not publicly explained how the scientific-review functions previously provided by the panel will be performed. EPA has not demonstrated that the current review structure provides scientific-review capabilities equivalent to those previously provided by the multidisciplinary review structure established for the review. The current review appears inconsistent with EPA's own recent and historical expertise determinations. The attached comments request clarification regarding: the status of the 2024 CASAC NO₂ Review Panel; whether EPA's determination regarding needed expertise has changed; how EPA will provide the breadth and depth of expertise previously identified as necessary; how EPA will provide multidisciplinary deliberation, evidence integration, review of causal determinations, and continuity across review stages; and whether EPA has evaluated the functional equivalence of the current review structure. The central question raised by the comments is: EPA determined in 2024 that multidisciplinary expertise was needed for this review, established a review panel to provide that expertise, and incorporated that panel into the review process. What explanation supports EPA's apparent decision not to continue utilizing that expertise structure during review of the draft ISA and subsequent review products, and how will the scientific-review functions previously provided by that structure now be performed? Attachment Information: The attached comment document contains citations to numerous supporting references. Due to Regulations.gov limits on file size (10 MB) and number of attachments (20 files per submission), not all cited references could be attached. Several cited EPA reports exceed the docket file-size limit. All references are fully identified in the submitted comments, and additional supporting reference materials are being submitted separately.