Finding of Failure To Attain the 1997 8-Hour Ozone Standards; California; San Joaquin Valley

ENVIRONMENTAL PROTECTION AGENCY <CFR>40 CFR Part 52</CFR> <DEPDOC>[EPA-R09-OAR-2024-0587; FRL-12483-01-R9]</DEPDOC> <SUBJECT>Finding of Failure To Attain the 1997 8-Hour Ozone Standards; California; San Joaquin Valley</SUBJECT> <HD SOURCE="HED">AGENCY:</HD> Environmental Protection Agency (EPA). <HD SOURCE="HED">ACTION:</HD> Proposed determination. <SUM> <HD SOURCE="HED">SUMMARY:</HD> The Environmental Protection Agency (EPA) is proposing to determine that the San Joaquin Valley, California area failed to attain the 1997 8-hour ozone national ambient air quality standard by its June 15, 2024 “Extreme” area attainment date. This proposed determination is based on quality-assured and certified ambient air quality monitoring data from 2021 through 2023. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> Comments must be received on or before August 11, 2025. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> Submit your comments, identified by Docket ID No. EPA-R09-OAR-2024-0587 at <E T="03">https://www.regulations.gov.</E> For comments submitted at <E T="03">Regulations.gov</E> , follow the online instructions for submitting comments. Once submitted, comments cannot be edited or removed from <E T="03">Regulations.gov</E> . The EPA may publish any comment received to its public docket. Do not submit electronically any information you consider to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Multimedia submissions (audio, video, etc.) must be accompanied by a written comment. The written comment is considered the official comment and should include discussion of all points you wish to make. The EPA will generally not consider comments or comment contents located outside of the primary submission ( <E T="03">i.e.,</E> on the web, cloud, or other file sharing system). For additional submission methods, please contact the person identified in the <E T="02">FOR FURTHER INFORMATION CONTACT</E> section. For the full EPA public comment policy, information about CBI or multimedia submissions, and general guidance on making effective comments, please visit <E T="03">https://www.epa.gov/dockets/commenting-epa-dockets.</E> If you need assistance in a language other than English or if you are a person with a disability who needs a reasonable accommodation at no cost to you, please contact the person identified in the <E T="02">FOR FURTHER INFORMATION CONTACT</E> section. <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> Laura Lawrence, EPA Region IX, ARD-2, 75 Hawthorne St., San Francisco, CA 94105: telephone number: (415) 972-3407; email address: <E T="03">lawrence.laura@epa.gov.</E> </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> Throughout this document, “we,” “us,” and “our” refer to the EPA. <HD SOURCE="HD1">Table of Contents</HD> <EXTRACT> <FP SOURCE="FP-2">I. Background</FP> <FP SOURCE="FP1-2">A. Regulatory Context</FP> <FP SOURCE="FP1-2">B. History of the 1997 8-Hour Ozone NAAQS in the San Joaquin Valley</FP> <FP SOURCE="FP-2">II. EPA Analysis</FP> <FP SOURCE="FP1-2">A. Applicable Statutory and Regulatory Provisions</FP> <FP SOURCE="FP1-2">B. Monitoring Network Considerations</FP> <FP SOURCE="FP1-2">C. Data Considerations</FP> <FP SOURCE="FP-2">III. Public Comment and Proposed Action</FP> <FP SOURCE="FP-2">IV. Statutory and Executive Order Reviews</FP> </EXTRACT> <HD SOURCE="HD1">I. Background</HD> <HD SOURCE="HD2">A. Regulatory Context</HD> Ground-level ozone pollution is formed from the reaction of volatile organic compounds (VOCs) and oxides of nitrogen (NO <E T="52">X</E> ) in the presence of sunlight. These two pollutants, referred to as ozone precursors, are emitted by many types of sources, including on- and off-road motor vehicles and engines, power plants and industrial facilities, and smaller area sources such as lawn and garden equipment and paints. Scientific evidence indicates that adverse public health effects occur following exposure to ozone, particularly in children and adults with lung disease. Breathing air containing ozone can reduce lung function and inflame airways, which can increase respiratory symptoms and aggravate asthma or other lung diseases. <SU>1</SU> <FTREF/> <FTNT> <SU>1</SU>  EPA, Health Effects of Ozone Pollution, available at <E T="03">https://www.epa.gov/ground-level-ozone-pollution/health-effects-ozone-pollution.</E> </FTNT> Under section 109 of the Clean Air Act (CAA or “Act”), the EPA promulgates national ambient air quality standards (NAAQS or “standards”) for pervasive air pollutants, such as ozone. The NAAQS are concentration levels whose attainment and maintenance the EPA has determined to be requisite to protect public health and welfare. In 1979, under section 109 of the CAA, the EPA established primary and secondary standards for ozone at 0.12 parts per million (ppm) averaged over a 1-hour period. <SU>2</SU> <FTREF/> <FTNT> <SU>2</SU>  44 FR 8202 (February 8, 1979). </FTNT> In July 1997, the EPA revised the primary and secondary NAAQS for ozone to set the acceptable level of ozone in the ambient air at 0.08 ppm, averaged over an 8-hour period. <SU>3</SU> <FTREF/> The EPA set the 1997 8-hour ozone NAAQS based on scientific evidence demonstrating that ozone causes adverse health effects at lower concentrations and over longer periods of time than was understood when the pre-existing 1-hour ozone standards were set. The EPA determined that the 8-hour standard would be more protective of human health, especially for children and for adults who are active outdoors, and for individuals with a preexisting respiratory disease, such as asthma. <FTNT> <SU>3</SU>  62 FR 38856 (July 18, 1997). Primary standards provide public health protection, including protecting the health of “sensitive” populations such as asthmatics, children, and the elderly. Secondary standards provide public welfare protection, including protection against decreased visibility and damage to animals, crops, vegetation, and buildings. Since the primary and secondary standards established in 1997 are set at the same level, we refer to them herein using the singular “1997 8-hour ozone NAAQS” or “1997 8-hour ozone standard.” </FTNT> In March 2008, the EPA completed another review of the primary and secondary ozone standards and tightened them further by lowering the level for both to 0.075 ppm. <SU>4</SU> <FTREF/> The EPA revoked the 1997 8-hour ozone NAAQS effective April 6, 2015;  <SU>5</SU> <FTREF/> however, to comply with anti-backsliding requirements of the Act, areas designated nonattainment at the time that the 1997 8-hour ozone NAAQS was revoked remain subject to certain requirements based on their classification at the time of revocation, including requirements related to nonattainment contingency measures under CAA sections 172(c)(9) and 182(c)(9) and, for “Severe” and “Extreme” areas, major source fee programs under CAA section 185. <SU>6</SU> <FTREF/> The EPA's determination that an area failed to attain by its attainment date, which is made under CAA section 301 and consistent with section 181(b)(2), triggers these anti-backsliding requirements. <E T="03">See South Coast Air Quality Mgmt. Dist.</E> v. <E T="03">EPA,</E> 882 F.3d 1138, 1147 (D.C. Cir. 2018). <FTNT> <SU>4</SU>  73 FR 16436 (March 27, 2008). </FTNT> <FTNT> <SU>5</SU>  80 FR 12264 (March 6, 2015). </FTNT> <FTNT> <SU>6</SU>  40 CFR 51.1100(o). </FTNT> The San Joaquin Valley ozone area, excluding areas of Indian country, <SU>7</SU> <FTREF/> is under the jurisdiction of the San Joaquin Valley Unified Air Pollution Control District (SJVUAPCD or “District”). Under California law, SJVUAPCD is responsible for adopting and implementing stationary source rules in the San Joaquin Valley, such as the fee program rules required under CAA section 185, while the California Air Resources Board (CARB) adopts and implements consumer products and mobile source rules subject to the requirements of CAA section 209. CARB submits the District and State rules to the EPA. <FTNT> <SU>7</SU>  “Indian country” as defined at 18 U.S.C. 1151 refers to: “(a) all land within the limits of any Indian reservation under the jurisdiction of the United States Government, notwithstanding the issuance of any patent, and, including rights-of-way running through the reservation, (b) all dependent Indian communities within the borders of the United States whether within the original or subsequently acquired territory thereof, and whether within or without the limits of a state, and (c) all Indian allotments, the Indian titles to which have not been extinguished, including rights-of-way running through the same.” </FTNT> An area is considered to have attained the 1997 8-hour ozone standard if there are no violations of the standard, as determined in accordance with 40 CFR 50.10, based on three consecutive years of complete, quality-assured, and certified monitoring data. A violation of the NAAQS occurs when the ambient ozone air quality monitoring data show that the 3-year average of the annual fourth-highest daily maximum 8-hour average ozone concentrations at an ozone monitor is greater than 0.08 ppm. <SU>8</SU> <FTREF/> <FTNT> <SU>8</SU>  40 CFR 50.10 and 40 CFR part 50, appendix I. As explained in section II.A. of this document, due to rounding and truncation conventions the computed 3-year average ozone concentration of 0.085 ppm is the smallest value that is greater than 0.08 ppm. </FTNT> <HD SOURCE="HD2">B. History of the 1997 8-Hour Ozone NAAQS in the San Joaquin Valley</HD> The San Joaquin Valley area consists of San Joaquin, Stanislaus, Merced, Madera, Fresno, Tulare, and Kings counties, and the western portion of Kern County. The area stretches over 250 miles from ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 31k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━