{"abstract":"On July 18, 1997, in accordance with sections 108 and 109 of the Clean Air Act (Act), EPA completed its review of the national ambient air quality standards (NAAQS) for ozone (O<INF>3</INF>) by promulgating revised primary and secondary standards (62 FR 38856; henceforth, \"1997 final rule\"). On May 14, 1999, the United States Court of Appeals for the District of Columbia Circuit (D.C. Circuit) remanded the O<INF>3</INF> NAAQS to EPA to consider, among other things, the alleged beneficial health effects of O<INF>3</INF> pollution in shielding the public from the \"harmful effects of the sun's ultraviolet rays.\" 175 F. 3d 1027 (D.C. Cir. 1999). Today's action provides EPA's proposed response to that aspect of the court's remand. As explained more fully below, based on its review of the air quality criteria and NAAQS for O<INF>3</INF> completed in 1997, and its additional assessment of the potential beneficial effects of tropospheric O<INF>3</INF>, EPA has provisionally determined that the information linking changes in patterns of ground-level O<INF>3</INF> concentrations likely to occur as a result of programs implemented to attain the 1997 O<INF>3</INF> NAAQS to changes in relevant exposures to UV-B radiation of concern to public health is too uncertain at this time to warrant any relaxation in the level of public health protection previously determined to be requisite to protect against the demonstrated direct adverse respiratory effects of exposure to O<INF>3</INF> in the ambient air. Further, the Administrator notes that it is the Agency's view that associated changes in UV-B radiation exposures of concern, using plausible but highly uncertain assumptions about likely changes in patterns of ground-level ozone concentrations, would likely be very small from a public health perspective. As a result, the revised O<INF>3</INF> NAAQS will remain set at a level of 0.08 parts per million (ppm), with a form based on the 3-year average of the annual fourth-highest daily maximum 8-hour average O<INF>3</INF> concentrations measured at each monitor within an area. The primary standard provides increased protection to the public, especially children and other at-risk populations, against a wide range of health effects directly induced by breathing O<INF>3</INF> in the ambient air, including decreased lung function (primarily in children active outdoors), increased respiratory symptoms (particularly in highly sensitive individuals), hospital admissions and emergency room visits for respiratory causes (among children and adults with pre-existing respiratory disease such as asthma), inflammation of the lung, and possible long-term damage to the lungs. The secondary standard provides increased protection to the public welfare against effects on vegetation, such as agricultural crop loss, damage to forests and ecosystems, and visible foliar injury to sensitive species associated with direct exposure to O<INF>3</INF> in the ambient air. Today's action constitutes EPA's proposed response to the part of the remand of the 1997 O<INF>3</INF> NAAQS by the D.C. Circuit related to whether tropospheric O<INF>3</INF> has a beneficial effect with regard to attenuation of naturally occurring solar radiation. Other issues related to the 1997 O<INF>3</INF> NAAQS are now before the D.C. Circuit for proceedings consistent with the February 27, 2001 opinion of the United States Supreme Court in this case, Whitman v. American Trucking Associations, 531 U.S. 457 (2001), and are not addressed by today's action.","action":"Proposed response to remand.","agencies":[{"raw_name":"ENVIRONMENTAL PROTECTION AGENCY","name":"Environmental Protection Agency","id":145,"url":"https://www.federalregister.gov/agencies/environmental-protection-agency","json_url":"https://www.federalregister.gov/api/v1/agencies/145","parent_id":null,"slug":"environmental-protection-agency"}],"body_html_url":"https://www.federalregister.gov/documents/full_text/html/2001/11/14/01-27820.html","cfr_references":[{"chapter":null,"citation_url":null,"part":50,"title":40}],"citation":"66 FR 57268","comment_url":null,"comments_close_on":"2002-01-14","correction_of":null,"corrections":[],"dates":"Comments on this proposed response must be received by January 14, 2002.","disposition_notes":null,"docket_ids":["FRL-7099-1"],"dockets":[],"document_number":"01-27820","effective_on":null,"end_page":57292,"executive_order_notes":null,"executive_order_number":null,"explanation":null,"full_text_xml_url":"https://www.federalregister.gov/documents/full_text/xml/2001/11/14/01-27820.xml","html_url":"https://www.federalregister.gov/documents/2001/11/14/01-27820/national-ambient-air-quality-standards-for-ozone-proposed-response-to-remand","images":{"EP14NO01.001":{"large":"https://img.federalregister.gov/EP14NO01.001/EP14NO01.001_large.png","medium":"https://img.federalregister.gov/EP14NO01.001/EP14NO01.001_medium.png","original_size":"https://img.federalregister.gov/EP14NO01.001/EP14NO01.001_original_size.png"}},"images_metadata":{"EP14NO01.001":{"large":{"identifier":"EP14NO01.001","content_type":"image/png","size":37421,"width":822,"sha":"535892f360f9c92103f235f12d8e232b","url":"https://img.federalregister.gov/EP14NO01.001/EP14NO01.001_large.png","height":781},"medium":{"identifier":"EP14NO01.001","content_type":"image/png","size":18145,"width":479,"sha":"d78c2555e23805409353e665dbbadd9f","url":"https://img.federalregister.gov/EP14NO01.001/EP14NO01.001_medium.png","height":455},"original_size":{"identifier":"EP14NO01.001","content_type":"image/png","size":102590,"width":3616,"sha":"8f9c9503580d95bc6b77a3eae89afa39","url":"https://img.federalregister.gov/EP14NO01.001/EP14NO01.001_original_size.png","height":3435}}},"json_url":"https://www.federalregister.gov/api/v1/documents/01-27820?publication_date=2001-11-14","mods_url":"https://www.govinfo.gov/metadata/granule/FR-2001-11-14/01-27820/mods.xml","not_received_for_publication":null,"page_length":25,"page_views":{"count":52,"last_updated":"2026-04-04 18:15:03 -0400"},"pdf_url":"https://www.govinfo.gov/content/pkg/FR-2001-11-14/pdf/01-27820.pdf","presidential_document_number":null,"proclamation_number":null,"public_inspection_pdf_url":null,"publication_date":"2001-11-14","raw_text_url":"https://www.federalregister.gov/documents/full_text/text/2001/11/14/01-27820.txt","regulation_id_number_info":{"2060-ZA11":null},"regulation_id_numbers":["2060-ZA11"],"regulations_dot_gov_info":{"supporting_documents":[{"title":"Record of telephone call between Senator Barbara Mikulski and Carol Browner, EPA to notify of PM/OZ Air Standards Rules [A-95-58-IV-E-165]","document_id":"EPA-HQ-OAR-2004-0394-8182"},{"title":"Letter to David B. Struhs, Boston, MA from John S. Seitz, Director, OAQPS, regarding Ozone / Particulate Matter NAAQS [A-95-58-IV-C-199]","document_id":"EPA-HQ-OAR-2004-0394-8173"},{"title":"Letter to Dr. R. Holmes Johnson, Kodiak, Alaska from John S. Seitz, Director, OAQPS, regarding Ozone / Particulate Matter NAAQS [A-95-58-IV-C-196]","document_id":"EPA-HQ-OAR-2004-0394-8170"},{"title":"Ponka, A. (1991) Asthma and Low Level Air Pollution in Helsinki. Archives of Environmental Health 46: 262-270. [A-95-58-II-I-378]","document_id":"EPA-HQ-OAR-2004-0394-8168"},{"title":"Plopper, C. G., Dungworth, D. L., Tyler, W. S., and Chow, C. K. (1979) Pulmonary Alterations in Rats Exposed to 0.2 and 0.1 ppm Ozone: A Correlated Morphological and Biochemical Study. Archives of Environmental Health 34: 390-395 [A-95-58-II-I-377]","document_id":"EPA-HQ-OAR-2004-0394-8167"},{"title":"Memorandum from Art Fraas and Chris Wolz, OMB, re: Meeting of an\nInteragency Group on the Environmental Protection Agency's\nReview of the National Ambient air quality Standard for ozone, Wednesday, April 6, 1994. [A-95-58-II-F-3]","document_id":"EPA-HQ-OAR-2004-0394-8160"},{"title":"Response to January 9,1997 letter to Administrator Browner from Tanner & Guin, P.C. [A-95-58-IV-C-21]","document_id":"EPA-HQ-OAR-2004-0394-1619"},{"title":"U.S. Environmental Protection Agency. (1996a) Air quality criteria for ozone and related photochemical oxidants. Research Triangle Park, NC...  [A-95-58-II-I-477]","document_id":"EPA-HQ-OAR-2004-0394-1529"},{"title":"Mathtech, Inc. (1994). The regional model farm (RMF): an agricultural sector benefits assessment model, version 3.0 for personal computers. Report to U.S. EPA, September  [A-95-58-II-I-304]","document_id":"EPA-HQ-OAR-2004-0394-1527"},{"title":"Record of meeting with American Public Health Association to discuss PM/OZ proposed Air Standards Rules. [A-95-58-IV-E-156]","document_id":"EPA-HQ-OAR-2004-0394-1506"}],"comments_url":"https://www.regulations.gov/docketBrowser?rpp=50&so=DESC&sb=postedDate&po=0&dct=PS&D=EPA-HQ-OAR-2004-0394","supporting_documents_count":1409,"docket_id":"EPA-HQ-OAR-2004-0394","regulation_id_number":null,"title":"Review of the National Ambient Air Quality Standards: Ozone","checked_regulationsdotgov_at":"2019-11-03T11:00:13Z"},"regulations_dot_gov_url":null,"significant":null,"signing_date":null,"start_page":57268,"subtype":null,"title":"National Ambient Air Quality Standards for Ozone: Proposed Response To Remand","toc_doc":"Ozone; response to remand","toc_subject":"Air programs:","topics":["Air pollution control","Carbon monoxide","Environmental protection","Lead","Nitrogen dioxide","Ozone","Particulate matter","Sulfur oxides"],"type":"Proposed Rule","volume":66}