Air Plan Approval; Texas; Reasonable Further Progress Plan for the Dallas-Fort Worth Ozone Nonattainment Area, 77770-77774 [2022-27603]

Download as PDF 77770 Federal Register / Vol. 87, No. 243 / Tuesday, December 20, 2022 / Proposed Rules consider and use in this proceeding, as appropriate. The Commission will consider all timely and responsive public comments that it receives on or before February 21, 2023. For information on the Commission’s privacy policy, including routine uses permitted by the Privacy Act, see https://www.ftc.gov/site-information/ privacy-policy. By direction of the Commission. April J. Tabor, Secretary. Note: the following statement will not appear in the Code of Federal Regulations. lotter on DSK11XQN23PROD with PROPOSALS1 Statement of Chair Lina M. Khan People decide what to buy, or not to buy, for all kinds of reasons. One of those reasons increasingly seems to be environmental impact. Before making a purchase, many American consumers want to know how a product contributes to climate change, or pollution, or the spread of microplastics. Businesses have noticed. Walk down the aisle at any major store—you’re likely to see packages trumpeting their low carbon footprint, their energy efficiency, or their quote-unquote ‘‘sustainability.’’ For the average consumer, it’s impossible to verify these claims. People who want to buy green products generally have to trust what it says on the box. That’s why it’s so important for companies making these claims to tell the truth. If they don’t, it distorts the market for environmentally friendly products. It puts honest companies, who bear the costs of green business practices, at a competitive disadvantage. And it harms consumers who want to make conscientious decisions about what products to buy and what businesses to support. The Commission has a strong track record of suing companies for deceptive environmental claims. It has reached several multi-million-dollar settlements just in the past few years.1 And, since 1992, the FTC has published the Guides for the Use of Environmental Marketing Claims.2 The ‘‘Green Guides,’’ as we call them, are administrative interpretations 1 United States v. Walmart Inc., Case No. 1:22– cv–00965 (D.D.C. Apr. 8, 2022), https:// www.ftc.gov/system/files/ftc_gov/pdf/ 2023173WalmartComplaint.pdf; United States v. Kohl’s Inc., Case No. 1:22–cv–00964 (D.D.C. Apr. 8, 2022), https://www.ftc.gov/system/files/ftc_gov/pdf/ 2023171KohlsOrder.pdf; FTC v. Truly Organic Inc., Case No. 1:19–cv–23832 (S.D. Fla. Sept. 18, 2019), https://www.ftc.gov/system/files?file=documents/ cases/truly_organic_stipulated_final_order_0.pdf. 2 The most recent revisions to the Guides occurred in 2012. See Guides for the Use of Environmental Marketing Claims, 77 FR 62122 (Oct. 11, 2012). VerDate Sep<11>2014 17:32 Dec 19, 2022 Jkt 259001 of the FTC Act as applied to environmental claims. They help companies avoid running afoul of the law’s ban on deceptive advertising. And they clarify the boundaries for fair, legal competition. To be effective, the Green Guides have to keep up with developments in both science and consumer perception. That’s why the Commission is commencing a regulatory review of the guides. At a broad level, the questions focus on whether any aspects are outdated and in need of revision. For example, recent reports suggest that many plastics that consumers believe they’re recycling actually end up in landfills. One question, then, is whether claims that a product is recyclable should reflect where a product ultimately ends up, not just whether it gets picked up from the curb. I’m particularly interested in receiving comments, including consumer perception research, on relatively emerging environmental topics. I’d like to thank staff for their hard work on this matter, and I encourage members of the public to submit comments to make sure their voice is heard. [FR Doc. 2022–27558 Filed 12–19–22; 8:45 am] BILLING CODE 6750–01–P ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 52 [EPA–R06–OAR–2020–0161; FRL–10428– 01–R6] Air Plan Approval; Texas; Reasonable Further Progress Plan for the DallasFort Worth Ozone Nonattainment Area Environmental Protection Agency (EPA). ACTION: Supplemental notice of proposed rulemaking. AGENCY: The Environmental Protection Agency (EPA) is supplementing a proposed approval published on October 9, 2020 (‘‘October 2020 proposal’’), for revisions to the Texas State Implementation Plan (SIP) to meet the Reasonable Further Progress (RFP) requirements for the Dallas-Fort Worth (DFW) serious nonattainment area for the 2008 ozone National Ambient Air Quality Standard (NAAQS). This proposal supplements the EPA’s October 2020 proposal with respect to the substitution of emission reductions of nitrogen oxide (NOX) for emission reductions of volatile organic compounds (VOC), based on comments SUMMARY: PO 00000 Frm 00022 Fmt 4702 Sfmt 4702 received during the public comment period for the October 2020 proposal. In the October 2020 proposal, the EPA proposed to approve the substitution of NOX emission reductions for VOC emission reductions but did not address how the substitution is consistent with the Clean Air Act (CAA). In this supplemental proposal, EPA is proposing to approve the substitution of NOX emission reductions for VOC emission reductions as consistent with section 182(c)(2)(C) of the CAA. The EPA is providing an opportunity for public comment on this supplemental proposal. The EPA is not reopening for comment the October 2020 proposal. Comments received on the October 2020 proposal and this supplemental proposal will be addressed in a final rule. DATES: Written comments on this supplemental proposal must be received on or before January 19, 2023. ADDRESSES: Submit your comments, identified by Docket No. EPA–R06– OAR–2020–0161, at https:// www.regulations.gov or via email to paige.carrie@epa.gov. Follow the online instructions for submitting comments. Once submitted, comments cannot be edited or removed from Regulations.gov. 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 (i.e., on the web, cloud, or other file sharing system). For additional submission methods, please contact Carrie Paige, 214–665–6521, paige.carrie@epa.gov. For the full EPA public comment policy, information about CBI or multimedia submissions, and general guidance on making effective comments, please visit https:// www.epa.gov/dockets/commenting-epadockets. Docket: The index to the docket for this action is available electronically at www.regulations.gov. While all documents in the docket are listed in the index, some information may not be publicly available due to docket file size restrictions or content (e.g., CBI). FOR FURTHER INFORMATION CONTACT: Carrie Paige, EPA Region 6 Office, Infrastructure & Ozone Section, 214– E:\FR\FM\20DEP1.SGM 20DEP1 Federal Register / Vol. 87, No. 243 / Tuesday, December 20, 2022 / Proposed Rules 665–6521, paige.carrie@epa.gov. Out of an abundance of caution for members of the public and our staff, the EPA Region 6 office may be closed to the public to reduce the risk of transmitting COVID– 19. The EPA Region 6 office encourages the public to submit comments via https://www.regulations.gov. Please call or email the contact listed above if you need alternative access to material indexed but not provided in the docket. SUPPLEMENTARY INFORMATION: Throughout this document, ‘‘we,’’ ‘‘us,’’ and ‘‘our’’ refers to the EPA. by November 9, 2020. We received relevant adverse comments on our proposal that included, among other comments, that our proposal did not address how the substitution of NOX emission reductions for VOC emission reductions in the DFW RFP is consistent with the CAA. Thus, we are addressing the NOX substitution in this supplemental proposal action. All comments received on our October 2020 proposal and this supplemental proposal will be addressed in the final action. I. Background A. An Overview of Ozone Chemistry and NOX Substitution Effects lotter on DSK11XQN23PROD with PROPOSALS1 On May 13, 2020, the Texas Commission on Environmental Quality (TCEQ or State) submitted to EPA a SIP revision addressing RFP requirements for the 2008 8-hour ozone NAAQS for the two serious ozone nonattainment areas in Texas—the DFW and HoustonGalveston-Brazoria (HGB) areas. On October 9, 2020 (85 FR 64084), we published a proposed rule to approve those portions of the May 13, 2020, Texas SIP revision addressing the DFW RFP requirements.1 In this supplemental proposal, we refer to the May 13, 2020, Texas SIP revision as ‘‘the RFP submittal’’ and we refer to our October 9, 2020, proposed action and Technical Support Document (TSD) as ‘‘the October 2020 proposal.’’ 2 In our October 2020 proposal, we provided information on ozone formation, the ozone standards, area designations, related SIP revision requirements under the CAA, and the EPA’s implementing regulations for the 2008 ozone standards, referred to as the 2008 Ozone SIP Requirements Rule (‘‘2008 Ozone SRR’’).3 The DFW Area, comprising Collin, Dallas, Denton, Ellis, Johnson, Kaufman, Parker, Rockwall, Tarrant, and Wise counties was classified as Serious nonattainment for the 2008 ozone standards and as such was subject to the serious area requirements, one of which was to demonstrate reasonable further progress in reducing VOC.4 In demonstrating RFP, NOX emission reductions may be substituted for VOC reductions with the appropriate justification. Comments on our October 2020 proposal were required to be received 1 We addressed the RFP for the HGB serious ozone nonattainment area in a separate rulemaking. See 86 FR 24717 (May 10, 2021). 2 The RFP submittal and our October 2020 proposal are provided in the docket for this action. 3 See 80 FR 12264 (March 6, 2015). 4 The EPA’s recent final determination that the DFW Serious nonattainment area failed to attain the 2008 ozone NAAQS by the area’s attainment date is outside the scope of this action. 87 FR 60926 (October 7, 2022). VerDate Sep<11>2014 17:32 Dec 19, 2022 Jkt 259001 As explained in our October 2020 proposal, ground-level ozone is formed when VOC and NOX react in the presence of sunlight.5 However, rather than varying directly with emissions of its precursors, ozone changes in a nonlinear fashion with the concentrations of its precursors. As described in EPA’s Health Risk and Exposure Assessment for Ozone,6 NOX emissions lead to both the formation and destruction of ozone, depending on the local concentrations of NOX, VOC, and radicals such as the hydroxyl (OH) and hydroperoxy (HO2) radicals. In areas dominated by fresh emissions of NOX, these radicals are removed via the production of nitric acid (HNO3), which lowers the ozone formation rate. In addition, the depletion of ozone by reaction with NOX is called ‘‘titration’’ and is often found in downtown metropolitan areas, especially near busy streets and roads, and in power plant emission plumes.7 This ‘‘titration’’ results in ozone concentrations that can be much lower than in surrounding areas. Titration is usually confined to areas close to strong NOX sources, and the NO2 formed can lead to ozone formation later and further downwind. Consequently, ozone response to reductions in NOX emissions is complex and may include ozone decreases at some times and locations and increases in ozone at other times and locations. In areas with low NOX concentrations, such as those found in remote 5 VOC and NO are also referred to as ozone X precursors. 6 EPA, Health Risk and Exposure Assessment (HREA) for Ozone Final Report, August 2014. Available at https://www.epa.gov/naaqs/ozone-o3standards-risk-and-exposure-assessments-reviewcompleted-2015. 7 Oxides of nitrogen (NO ) can be in the form of X nitric oxide (NO), nitrite (NO2), etc. Ozone (O3) is a highly reactive gas that decays to ordinary oxygen (O2). When O3 reacts with NOX, the result oxidizes the NOX, i.e., the molecule of oxygen (O) moves from the O3 to the NOX. For example, O3 + NO forms NO2 + O2. This reaction can also move in the opposite direction, to form ozone. PO 00000 Frm 00023 Fmt 4702 Sfmt 4702 77771 continental areas and rural and suburban areas downwind of urban centers, the net production of ozone typically varies directly with NOX concentrations and increases with increasing NOX emissions. In general, the rate of ozone production is limited by either the concentration of VOC or NOX. Ozone formation resulting from these two precursors relies on the relative sources of OH and NOX. When OH radicals are abundant and are not depleted by reaction with NOX and/or other species, ozone production is referred to as being ‘‘NOX-limited.’’ 8 In this situation, ozone concentrations are most effectively reduced by lowering NOX emissions, rather than lowering emissions of VOCs. When the abundance of OH and other radicals is limited either through low production or reactions with NOX and other species, ozone production is sometimes called ‘‘VOC-limited’’ or ‘‘NOX-saturated’’ and ozone is most effectively reduced by lowering VOCs. However, even in NOX-saturated conditions, very large decreases in NOX emissions can cause the ozone formation regime to become NOXlimited. Consequently, reductions in NOX emissions (when large), can make further emissions reductions more effective at reducing ozone. Between the NOX-limited and NOX-saturated extremes there is a transitional region, where ozone is less sensitive to marginal changes in either NOX or VOCs. In rural areas and downwind of urban areas, ozone production is generally NOX-limited. However, across urban areas with high populations, conditions may vary. CAA section 182(c)(2)(C) requires serious and above ozone nonattainment areas to make reasonable progress in reducing VOC, and also grants the EPA discretion to define the conditions under which NOX reductions may be substituted for or combined with VOC reductions ‘‘in order to maximize the reduction in ozone air pollution’’ and does not further specify the conditions that represent an ‘‘equivalent’’ reduction in ozone. For instance, it does not require a specific concentration test at every monitor or at specific locations within an area. No such requirement appears in the CAA’s other provisions governing the RFP demonstration, which define specific percentage reductions aimed at ensuring timely attainment of the NAAQS, or in the 8 See EPA’s Integrated Science Assessment (ISA) for Ozone and Related Photochemical Oxidants, Final Report, February 2013, section 3.2.4, posted at https://www.epa.gov/naaqs/ozone-o3-standardsintegrated-science-assessments-review-completed2015. E:\FR\FM\20DEP1.SGM 20DEP1 77772 Federal Register / Vol. 87, No. 243 / Tuesday, December 20, 2022 / Proposed Rules EPA’s 1993 NOX Substitution Guidance, which describes a recommended procedure for states to utilize NOX substitution.9 We interpret CAA section 182(c)(2)(C) and these supporting authorities as properly reflecting Congress’s intent to allow NOX reductions to be considered within an RFP demonstration so long as these reductions are at least as effective as using VOC reductions in reducing ozone. lotter on DSK11XQN23PROD with PROPOSALS1 B. Ozone Chemistry in the DFW Area The dynamics of ozone formation in the DFW area, including the proportion of VOC to NOX (‘‘VOC: NOX ratio’’), are described in Appendix D of the DFW Serious Area Attainment Demonstration SIP Revision for the 2008 Ozone NAAQS.10 Appendix D is the conceptual model for the DFW area, providing details on ozone transport, as well as trends and formation. The highest levels of ozone typically occur north and northwest of the Dallas urban core, e.g., at the Denton Airport South and Grapevine Fairway monitors — these monitors are often downwind during the ozone season, as surface winds during this time are predominately from the south and southeast.11 The Grapevine Fairway monitor, northwest of the Dallas urban core, was the ‘‘controlling’’ monitor in 2018 and 2020; the Dallas North monitor, north of the Dallas urban core, was the controlling monitor in 2019; and the Pilot Point monitor, northnorthwest of the Dallas urban core, was the controlling monitor in 2021.12 The controlling monitor is the monitor with the highest ozone design value (DV) in the nonattainment area. The DV is the annual fourth highest daily maximum 8hour average ozone concentration and is the metric to determine compliance with the 2008 ozone NAAQS. Thus, the controlling monitor determines the ozone DV for the nonattainment area. The DFW area is the fourth largest metropolitan area in the United States with about 7.5 million residents.13 9 EPA’s NO Substitution Guidance is posted in X the docket for this rulemaking and at https:// www3.epa.gov/ttn/naaqs/aqmguide/collection/cp2_ old/19931201_oaqps_nox_substitution_ guidance.pdf. 10 Henceforth referred to as ‘‘Appendix D’’ and posted in the docket for this action. 11 A map showing the location of the 20 ozone monitors in the DFW area is posted in the docket for this action. 12 The TCEQ posts the annual fourth highest daily maximum 8-hour average ozone concentrations. See https://www.tceq.texas.gov/cgi-bin/compliance/ monops/8hr_attainment.pl. 13 U.S. Census Bureau, 2020 census data for the 10 counties comprising the DFW area. See https:// www.census.gov/library/visualizations/interactive/ 2020-population-and-housing-state-data.html. VerDate Sep<11>2014 17:32 Dec 19, 2022 Jkt 259001 Ozone precursor emissions (both NOX and VOC) in the DFW area and particularly the urban core of Dallas and Fort Worth have historically been dominated by mobile source emissions.14 In recent years however, only the NOX emissions in the DFW area are dominated by mobile sources and VOC emissions are dominated by area sources.15 Appendix D mentions that the highest average NOX concentrations have been measured at the Dallas Hinton Street ozone monitor, located in the Dallas urban core near several busy roadways. Monitors located to the south and southeast of Dallas County, in areas that are relatively rural, have measured the lowest NOX concentrations. NOX concentrations in the DFW area have declined since the mid-1980s and NOX concentrations at the Dallas Hinton Street monitor showed a 50 percent (%) decrease from 2003 through 2013. We believe that NOX emissions have continued to decrease since 2013, as seen in the more recent and lower emission inventories for the DFW area cited earlier (81 FR 88124 and 87 FR 56891). Appendix D mentions that reductions in NOX concentrations outside the DFW urban core are not as large as those observed close to its center, which suggests that the measured decreases may be a result of reductions in NOX emissions from mobile sources. Decreases in VOC concentration have also been measured in the DFW area but are not as dramatic as the decreases in NOX emissions. The TCEQ uses analyses in Appendix D to conclude that monitors to the northwest and on the edges of the DFW area are transitional or NOX-limited, indicating that NOX controls would be more effective at controlling ozone in these areas. Monitors to the northwest include the Denton Airport South, Grapevine Fairway, Keller, and Eagle Mountain Lake, and monitors on the edges of the DFW area include Pilot Point, Parker County, Granbury, Cleburne Airport, Italy, Corsicana Airport, Kaufman, Rockwall Heath, and Greenville. Of these monitors, only the Grapevine Fairway, Pilot Point, and Cleburne Airport monitors had ozone DVs above 75 ppb from 2018 through 2021. Of the 20 ozone monitors in the DFW area, 15 have ozone DVs at or below 75 ppb from 2018 through 2021 and thus, are not relevant to the discussion on NOX substitution since these monitors 14 For example, see the approved emission inventories at 73 FR 58475 (October 7, 2008). 15 See the emission inventories approved at 79 FR 67068 (November 12, 2014), 81 FR 88124 (December 7, 2016), and 87 FR 56891 (September 16, 2022). PO 00000 Frm 00024 Fmt 4702 Sfmt 4702 are not violating the 2008 ozone NAAQS. Four of the five monitors with ozone DVs above 75 ppb (Frisco, Dallas North, Grapevine Fairway, and Pilot Point) are north and northwest (and typically downwind) from the Dallas urban core and thus, consistent with our earlier discussion on ozone chemistry and the TCEQ’s analyses in Appendix D, we would expect NOX controls to be more effective than VOC controls for reducing ozone at these monitors. The fifth monitor with ozone DVs above 75 ppb is the Cleburne Airport monitor, which, as noted earlier, is on the edge of the DFW area and is south-southwest of the DFW urban core. While surface winds during the ozone season are predominately from the south and southeast, it is not unusual for surface winds to flow from the northeast (and thus, flow downwind from the DFW urban core) on days when the Cleburne Airport monitor exceeds the ozone standard.16 Therefore, consistent with our earlier discussion on ozone chemistry and the TCEQ’s analyses in Appendix D, we would expect NOX controls to be more effective than VOC controls for controlling ozone at this monitor, too. A new analysis published by EPA authors looks at ozone formation regimes in 2007 and 2016 in ozone nonattainment areas, including the DFW area.17 Details for DFW are included in the supplemental information of that paper which suggests that: (1) day-ofweek analysis points to the DFW area as a whole being NOX-limited in 2016 but the controlling monitor being ‘‘transitional,’’ and (2) photochemical model sensitivity analysis (i.e., model predictions of how ozone will change with emissions perturbations) predicts that in 2016 all locations in the DFW area were NOX-limited on average across days with ozone levels above 70 ppb (there could be some variability among those days). The controlling monitor in 2016 was the Denton Airport South monitor, northwest of the Dallas 16 See the 2014–2016 back trajectory analyses from the Cleburne Airport monitor provided in the Dallas-Fort Worth and Houston-Galveston-Brazoria Nonattainment Areas Final Area Designations for the 2015 Ozone National Ambient Air Quality Standards Technical Support Document, Figure 6b on page 18. Figure 6b shows winds predominantly from the northeast on days when the Cleburne Airport monitor exceeded the 2015 ozone NAAQS. This TSD is posted at https://www.regulations.gov/ document/EPA-HQ-OAR-2017-0548-0403. 17 Reference: Koplitz, S; Simon, H; Henderson, B; Liljegren, J; Tonnesen, G; Whitehill, A; and Wells, B. Changes in Ozone Chemical Sensitivity in the United States from 2007 to 2016. ACS Environ. Au 2022, 2, 206–222. See also https://doi.org/10.1021/ acsenvironau.1c00029. This article and the supplemental information are in the docket for this action. E:\FR\FM\20DEP1.SGM 20DEP1 lotter on DSK11XQN23PROD with PROPOSALS1 Federal Register / Vol. 87, No. 243 / Tuesday, December 20, 2022 / Proposed Rules urban core, with an ozone DV of 80 ppb.18 An analysis of ozone and NOX for each day of the week for 1997–2013 is also provided in Appendix D. In the scientific literature, day-of-week analysis has been used to infer ozone chemical regimes.19 In many urban areas, NOX concentrations decrease on weekends while VOC concentrations remain fairly constant due to shifts in heavy-duty diesel vehicle patterns throughout the week. All other conditions being equal, if ozone concentrations decrease in parallel with these lower weekend NOX values that suggests a location has NOX-limited ozone formation regime. Conversely higher weekend ozone concentrations suggest a VOC-limited ozone formation regime. The analysis presented in Appendix D finds that on Sundays, ozone and NOX concentrations were significantly lower compared to other days of the week and on Fridays, ozone and NOX concentrations were higher compared to other days of the week. Appendix D notes that the highest NOX concentrations (on Fridays) are also when traffic (on-road mobile source activity) is at its peak. Appendix D further presents site-level ozone concentrations by day-of-week and shows that the highest ozone concentrations occur mid-week at both an urban core site (Dallas Hinton Street) and at one of the controlling monitors (Grapevine Fairway) suggesting NOXlimited conditions in these locations. The analysis in Appendix D reviewed the number of days with ozone concentrations greater than 75 ppb (‘‘high ozone days’’) for each day of the week at all monitoring sites in the DFW area and found that fewer high ozone days occur on Sundays compared to other days of the week. Sunday had 85 high ozone days and Monday had the second lowest number of high ozone days—103. High ozone days occur most often on Fridays, with 137 days. While the day-of-week analysis is for years 1997–2013, NOX reductions in the DFW area since 2013 are expected to result in more NOX-limited conditions than would have been present during the period of this analysis. From 2018 through 2021, 15 of the 20 monitors in the DFW area recorded ozone DVs at or below 75 ppb and five monitors had ozone DVs above 75 ppb: Pilot Point, Grapevine Fairway, Dallas North, Frisco, and Cleburne Airport. 18 The ozone DV at the Denton Airport South monitor was at or below 75 ppb from 2018 through 2021. 19 Please see the list of references provided in the docket for this action. VerDate Sep<11>2014 17:32 Dec 19, 2022 Jkt 259001 The TCEQ’s analyses in Appendix D indicate that NOX controls would be more effective at controlling ozone in these monitor locations. The TCEQ’s findings here are consistent with our understanding of ozone chemistry and recent analysis of ozone formation regimes described earlier. Therefore, we find the TCEQ’s use of NOX substitution in the DFW area reasonable, especially where the DFW monitors have DVs above 75 ppb from 2018 through 2021. II. NOX Substitution in the TX RFP SIP for the DFW Area As described here and in our October 2020 proposal, the DFW serious nonattainment area for the 2008 ozone NAAQS had an attainment date of July 20, 2021.20 The attainment year ozone season is the ozone season immediately preceding a nonattainment area’s maximum attainment date (see 40 CFR 51.1100(h)). Therefore, pursuant to CAA section 182(c)(2) and 40 CFR 51.1110, the RFP submittal for the DFW serious nonattainment area must demonstrate emissions reductions within the nonattainment area of three percent per year from January 1, 2018, to the end of the attainment year and thus, a nine percent reduction in emissions is required from January 1, 2018, through December 31, 2020. In addition, because the State has already satisfied the 15 percent VOC emissions reduction requirement for the DFW area,21 all 10 counties in the DFW Serious nonattainment area may substitute NOX reductions for VOC, consistent with the 2008 Ozone SRR (see 80 FR 12264, 12271), 40 CFR 51.1110, and EPA’s NOX Substitution Guidance. The RFP submittal for the DFW area provides the required nine percent reductions as eight percent NOX emissions reductions and one percent VOC emissions reductions. As noted earlier, Appendix D describes the highest levels of NOX in the urban core and the highest concentrations of ozone recorded at monitors downwind of the urban core, predominantly in the north and northwest portions of the DFW area. Appendix D also describes a transitional regime in the DFW urban core and at the Eagle Mountain Lake monitor however, the monitors in the DFW urban core and the Eagle Mountain Lake monitor have ozone DVs at or below 75 ppb from 2018 through 2021 and thus, are not relevant to the discussion on NOX substitution. Appendix D also describes, consistent 20 See 84 FR 44238, (August 23, 2019). The EPA’s final determination that the DFW area did not meet the July 20, 2021, attainment date for the 2008 ozone NAAQS is outside the scope of this action (see 87 FR 60926). 21 See 81 FR 88124 (December 7, 2016). PO 00000 Frm 00025 Fmt 4702 Sfmt 4702 77773 with EPA’s discussion on ozone chemistry elsewhere in this action, that monitors to the north, northwest, and on the edges of the DFW area are transitional or NOX-limited. As mentioned earlier, four of the five monitors that recorded violations of the 2008 ozone NAAQS between 2018 and 2021 are north and northwest of the Dallas urban core: Pilot Point, Grapevine Fairway, Dallas North, and Frisco. The fifth monitor—the Cleburne Airport monitor—is on the southsouthwest edge of the DFW area. Finally, the State’s review of ozone and NOX for each day of the week links levels of NOX with ozone levels, indicating that decreasing levels of NOX would result in decreasing levels of ozone. Because ambient NOX and ozone data indicate those areas of DFW with the highest ozone values are NOXlimited, and because there are no violating monitors in the DFW areas described as VOC-limited, we agree with Texas that reductions in NOX are at least as effective in reducing ozone as VOC reductions. In addition, based on the EPA’s analysis referenced earlier 22 and the TCEQ’s day-of-the-week analyses of NOX concentrations and ozone levels, we would also expect NOX reductions at the DFW urban core monitors to be at least as effective in reducing ozone as VOC reductions. Therefore, we find that the State’s use of NOX substitution is warranted and appropriately implemented, and we propose to approve the NOX substitution provided in the RFP submittal for the DFW serious nonattainment area for the 2008 ozone NAAQS. III. Environmental Justice Considerations Executive Order 12898 (Federal Actions to Address Environmental Justice in Minority Populations and Low-Income Populations, 59 FR 7629, February 16, 1994) directs Federal agencies to identify and address ‘‘disproportionately high and adverse human health or environmental effects’’ of their actions on minority populations and low-income populations to the greatest extent practicable and permitted by law. The EPA defines environmental justice (EJ) as ‘‘the fair treatment and meaningful involvement of all people regardless of race, color, national origin, or income with respect to the development, implementation, 22 Koplitz, S; Simon, H; Henderson, B; Liljegren, J; Tonnesen, G; Whitehill, A; and Wells, B. Changes in Ozone Chemical Sensitivity in the United States from 2007 to 2016. ACS Environ. Au 2022, 2, 206– 222. This article and the supplemental information are in the docket for this action. E:\FR\FM\20DEP1.SGM 20DEP1 77774 Federal Register / Vol. 87, No. 243 / Tuesday, December 20, 2022 / Proposed Rules and enforcement of environmental laws, regulations, and policies.’’ The EPA further defines the term fair treatment to mean that ‘‘no group of people should bear a disproportionate burden of environmental harms and risks, including those resulting from the negative environmental consequences of industrial, governmental, and commercial operations or programs and policies.’’ 23 For this proposed action, the EPA conducted screening analyses using the EJScreen (Version 2.1) tool. We conducted the analyses for the purpose of providing information to the public, not as a basis of our proposed action. The EJScreen analysis reports are available in the docket for this rulemaking. The EPA found, based on the EJScreen analyses, that this proposed action will not have disproportionately high or adverse human health or environmental effects on communities with EJ concerns, as the RFP is an accounting of ozone precursor emission reductions throughout the 10county DFW nonattainment area. IV. Supplemental Proposed Action The EPA is supplementing our October 2020 proposal addressing revisions to the Texas SIP to meet the RFP requirements for the DFW serious nonattainment area for the 2008 ozone NAAQS. In this supplemental proposal, we are proposing to approve the substitution of NOX emission reductions for VOC emission reductions as consistent with section 182(c)(2)(C) of the CAA. The EPA is providing an opportunity for public comment on this supplemental proposal. However, we are not reopening for comment our October 2020 proposal. The EPA will address all comments received on our October 2020 proposal and on this supplemental proposal in our final action. lotter on DSK11XQN23PROD with PROPOSALS1 V. Statutory and Executive Order Reviews Under the CAA, the Administrator is required to approve a SIP submission that complies with the provisions of the Act and applicable Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in reviewing SIP submissions, the EPA’s role is to approve state choices, provided that they meet the criteria of the CAA. Accordingly, this action merely proposes to approve state law as meeting Federal requirements and does not impose additional requirements beyond those imposed by state law. For that reason, this action: 23 See https://www.epa.gov/environmentaljustice/ learn-about-environmental-justice. VerDate Sep<11>2014 17:32 Dec 19, 2022 Jkt 259001 • Is not a ‘‘significant regulatory action’’ subject to review by the Office of Management and Budget under Executive Orders 12866 (58 FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 21, 2011); • Does not impose an information collection burden under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.); • Is certified as not having a significant economic impact on a substantial number of small entities under the Regulatory Flexibility Act (5 U.S.C. 601 et seq.); • Does not contain any unfunded mandate or significantly or uniquely affect small governments, as described in the Unfunded Mandates Reform Act of 1995 (Pub. L. 104–4); • Does not have federalism implications as specified in Executive Order 13132 (64 FR 43255, August 10, 1999); • Is not an economically significant regulatory action based on health or safety risks subject to Executive Order 13045 (62 FR 19885, April 23, 1997); • Is not a significant regulatory action subject to Executive Order 13211 (66 FR 28355, May 22, 2001); • Is not subject to requirements of section 12(d) of the National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) because application of those requirements would be inconsistent with the CAA; and • Does not provide EPA with the discretionary authority to address, as appropriate, disproportionate human health or environmental effects, using practicable and legally permissible methods, under Executive Order 12898 (59 FR 7629, February 16, 1994). In addition, the SIP is not approved to apply on any Indian reservation land or in any other area where EPA or an Indian tribe has demonstrated that a tribe has jurisdiction. In those areas of Indian country, the proposed rule does not have tribal implications and will not impose substantial direct costs on tribal governments or preempt tribal law as specified by Executive Order 13175 (65 FR 67249, November 9, 2000). List of Subjects in 40 CFR Part 52 Environmental protection, Air pollution control, Incorporation by reference, Nitrogen dioxide, Ozone, Volatile organic compounds. Authority: 42 U.S.C. 7401 et seq. Dated: December 15, 2022. Earthea Nance, Regional Administrator, Region 6. [FR Doc. 2022–27603 Filed 12–19–22; 8:45 am] BILLING CODE 6560–50–P PO 00000 Frm 00026 Fmt 4702 Sfmt 4702 ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 52 [EPA–R09–OAR–2022–0681; FRL–10386– 01–R9] Approval of Air Quality Implementation Plans; Vehicle Miles Traveled Emissions Offset Demonstrations for the 2015 Ozone Standards; California Environmental Protection Agency (EPA). ACTION: Proposed rule. AGENCY: The Environmental Protection Agency (EPA) is proposing to approve revisions to the California state implementation plan (SIP) concerning vehicle miles traveled (VMT) offset demonstrations for the Los Angeles— South Coast Air Basin (South Coast), Riverside County (Coachella Valley), Los Angeles—San Bernardino Counties (West Mojave Desert), and San Joaquin Valley nonattainment areas (NAAs) for the 2015 ozone national ambient air quality standards (NAAQS). The EPA is proposing to approve these revisions because they demonstrate that California has added or implemented specific enforceable transportation control strategies and transportation control measures to offset the growth in emissions from growth in VMT and vehicle trips. We are proposing to approve these revisions under the Clean Air Act (CAA or ‘‘the Act’’), which establishes VMT offset demonstration requirements for ozone nonattainment areas classified as ‘‘Severe’’ or ‘‘Extreme.’’ SUMMARY: Written comments must arrive on or before January 19, 2023. ADDRESSES: Submit your comments, identified by Docket ID No. EPA–R09– OAR–2022–0681 at https:// www.regulations.gov. For comments submitted at Regulations.gov, follow the online instructions for submitting comments. Once submitted, comments cannot be edited or removed from Regulations.gov. 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 DATES: E:\FR\FM\20DEP1.SGM 20DEP1

Agencies

[Federal Register Volume 87, Number 243 (Tuesday, December 20, 2022)]
[Proposed Rules]
[Pages 77770-77774]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-27603]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R06-OAR-2020-0161; FRL-10428-01-R6]


Air Plan Approval; Texas; Reasonable Further Progress Plan for 
the Dallas-Fort Worth Ozone Nonattainment Area

AGENCY: Environmental Protection Agency (EPA).

ACTION: Supplemental notice of proposed rulemaking.

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SUMMARY: The Environmental Protection Agency (EPA) is supplementing a 
proposed approval published on October 9, 2020 (``October 2020 
proposal''), for revisions to the Texas State Implementation Plan (SIP) 
to meet the Reasonable Further Progress (RFP) requirements for the 
Dallas-Fort Worth (DFW) serious nonattainment area for the 2008 ozone 
National Ambient Air Quality Standard (NAAQS). This proposal 
supplements the EPA's October 2020 proposal with respect to the 
substitution of emission reductions of nitrogen oxide (NOX) 
for emission reductions of volatile organic compounds (VOC), based on 
comments received during the public comment period for the October 2020 
proposal. In the October 2020 proposal, the EPA proposed to approve the 
substitution of NOX emission reductions for VOC emission 
reductions but did not address how the substitution is consistent with 
the Clean Air Act (CAA). In this supplemental proposal, EPA is 
proposing to approve the substitution of NOX emission 
reductions for VOC emission reductions as consistent with section 
182(c)(2)(C) of the CAA. The EPA is providing an opportunity for public 
comment on this supplemental proposal. The EPA is not reopening for 
comment the October 2020 proposal. Comments received on the October 
2020 proposal and this supplemental proposal will be addressed in a 
final rule.

DATES: Written comments on this supplemental proposal must be received 
on or before January 19, 2023.

ADDRESSES: Submit your comments, identified by Docket No. EPA-R06-OAR-
2020-0161, at https://www.regulations.gov or via email to 
[email protected]. Follow the online instructions for submitting 
comments. Once submitted, comments cannot be edited or removed from 
Regulations.gov. 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 (i.e., on the web, cloud, or other file sharing system). For 
additional submission methods, please contact Carrie Paige, 214-665-
6521, [email protected]. For the full EPA public comment policy, 
information about CBI or multimedia submissions, and general guidance 
on making effective comments, please visit https://www.epa.gov/dockets/commenting-epa-dockets.
    Docket: The index to the docket for this action is available 
electronically at www.regulations.gov. While all documents in the 
docket are listed in the index, some information may not be publicly 
available due to docket file size restrictions or content (e.g., CBI).

FOR FURTHER INFORMATION CONTACT: Carrie Paige, EPA Region 6 Office, 
Infrastructure & Ozone Section, 214-

[[Page 77771]]

665-6521, [email protected]. Out of an abundance of caution for 
members of the public and our staff, the EPA Region 6 office may be 
closed to the public to reduce the risk of transmitting COVID-19. The 
EPA Region 6 office encourages the public to submit comments via 
https://www.regulations.gov. Please call or email the contact listed 
above if you need alternative access to material indexed but not 
provided in the docket.

SUPPLEMENTARY INFORMATION: Throughout this document, ``we,'' ``us,'' 
and ``our'' refers to the EPA.

I. Background

    On May 13, 2020, the Texas Commission on Environmental Quality 
(TCEQ or State) submitted to EPA a SIP revision addressing RFP 
requirements for the 2008 8-hour ozone NAAQS for the two serious ozone 
nonattainment areas in Texas--the DFW and Houston-Galveston-Brazoria 
(HGB) areas. On October 9, 2020 (85 FR 64084), we published a proposed 
rule to approve those portions of the May 13, 2020, Texas SIP revision 
addressing the DFW RFP requirements.\1\ In this supplemental proposal, 
we refer to the May 13, 2020, Texas SIP revision as ``the RFP 
submittal'' and we refer to our October 9, 2020, proposed action and 
Technical Support Document (TSD) as ``the October 2020 proposal.'' \2\
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    \1\ We addressed the RFP for the HGB serious ozone nonattainment 
area in a separate rulemaking. See 86 FR 24717 (May 10, 2021).
    \2\ The RFP submittal and our October 2020 proposal are provided 
in the docket for this action.
---------------------------------------------------------------------------

    In our October 2020 proposal, we provided information on ozone 
formation, the ozone standards, area designations, related SIP revision 
requirements under the CAA, and the EPA's implementing regulations for 
the 2008 ozone standards, referred to as the 2008 Ozone SIP 
Requirements Rule (``2008 Ozone SRR'').\3\ The DFW Area, comprising 
Collin, Dallas, Denton, Ellis, Johnson, Kaufman, Parker, Rockwall, 
Tarrant, and Wise counties was classified as Serious nonattainment for 
the 2008 ozone standards and as such was subject to the serious area 
requirements, one of which was to demonstrate reasonable further 
progress in reducing VOC.\4\ In demonstrating RFP, NOX 
emission reductions may be substituted for VOC reductions with the 
appropriate justification.
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    \3\ See 80 FR 12264 (March 6, 2015).
    \4\ The EPA's recent final determination that the DFW Serious 
nonattainment area failed to attain the 2008 ozone NAAQS by the 
area's attainment date is outside the scope of this action. 87 FR 
60926 (October 7, 2022).
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    Comments on our October 2020 proposal were required to be received 
by November 9, 2020. We received relevant adverse comments on our 
proposal that included, among other comments, that our proposal did not 
address how the substitution of NOX emission reductions for 
VOC emission reductions in the DFW RFP is consistent with the CAA. 
Thus, we are addressing the NOX substitution in this 
supplemental proposal action. All comments received on our October 2020 
proposal and this supplemental proposal will be addressed in the final 
action.

A. An Overview of Ozone Chemistry and NOX Substitution 
Effects

    As explained in our October 2020 proposal, ground-level ozone is 
formed when VOC and NOX react in the presence of 
sunlight.\5\ However, rather than varying directly with emissions of 
its precursors, ozone changes in a nonlinear fashion with the 
concentrations of its precursors. As described in EPA's Health Risk and 
Exposure Assessment for Ozone,\6\ NOX emissions lead to both 
the formation and destruction of ozone, depending on the local 
concentrations of NOX, VOC, and radicals such as the 
hydroxyl (OH) and hydroperoxy (HO2) radicals. In areas 
dominated by fresh emissions of NOX, these radicals are 
removed via the production of nitric acid (HNO3), which 
lowers the ozone formation rate. In addition, the depletion of ozone by 
reaction with NOX is called ``titration'' and is often found 
in downtown metropolitan areas, especially near busy streets and roads, 
and in power plant emission plumes.\7\ This ``titration'' results in 
ozone concentrations that can be much lower than in surrounding areas. 
Titration is usually confined to areas close to strong NOX 
sources, and the NO2 formed can lead to ozone formation 
later and further downwind. Consequently, ozone response to reductions 
in NOX emissions is complex and may include ozone decreases 
at some times and locations and increases in ozone at other times and 
locations. In areas with low NOX concentrations, such as 
those found in remote continental areas and rural and suburban areas 
downwind of urban centers, the net production of ozone typically varies 
directly with NOX concentrations and increases with 
increasing NOX emissions.
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    \5\ VOC and NOX are also referred to as ozone 
precursors.
    \6\ EPA, Health Risk and Exposure Assessment (HREA) for Ozone 
Final Report, August 2014. Available at https://www.epa.gov/naaqs/ozone-o3-standards-risk-and-exposure-assessments-review-completed-2015.
    \7\ Oxides of nitrogen (NOX) can be in the form of 
nitric oxide (NO), nitrite (NO2), etc. Ozone 
(O3) is a highly reactive gas that decays to ordinary 
oxygen (O2). When O3 reacts with 
NOX, the result oxidizes the NOX, i.e., the 
molecule of oxygen (O) moves from the O3 to the 
NOX. For example, O3 + NO forms NO2 
+ O2. This reaction can also move in the opposite 
direction, to form ozone.
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    In general, the rate of ozone production is limited by either the 
concentration of VOC or NOX. Ozone formation resulting from 
these two precursors relies on the relative sources of OH and 
NOX. When OH radicals are abundant and are not depleted by 
reaction with NOX and/or other species, ozone production is 
referred to as being ``NOX-limited.'' \8\ In this situation, 
ozone concentrations are most effectively reduced by lowering 
NOX emissions, rather than lowering emissions of VOCs. When 
the abundance of OH and other radicals is limited either through low 
production or reactions with NOX and other species, ozone 
production is sometimes called ``VOC-limited'' or ``NOX-
saturated'' and ozone is most effectively reduced by lowering VOCs. 
However, even in NOX-saturated conditions, very large 
decreases in NOX emissions can cause the ozone formation 
regime to become NOX-limited. Consequently, reductions in 
NOX emissions (when large), can make further emissions 
reductions more effective at reducing ozone. Between the 
NOX-limited and NOX-saturated extremes there is a 
transitional region, where ozone is less sensitive to marginal changes 
in either NOX or VOCs. In rural areas and downwind of urban 
areas, ozone production is generally NOX-limited. However, 
across urban areas with high populations, conditions may vary.
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    \8\ See EPA's Integrated Science Assessment (ISA) for Ozone and 
Related Photochemical Oxidants, Final Report, February 2013, section 
3.2.4, posted at https://www.epa.gov/naaqs/ozone-o3-standards-integrated-science-assessments-review-completed-2015.
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    CAA section 182(c)(2)(C) requires serious and above ozone 
nonattainment areas to make reasonable progress in reducing VOC, and 
also grants the EPA discretion to define the conditions under which 
NOX reductions may be substituted for or combined with VOC 
reductions ``in order to maximize the reduction in ozone air 
pollution'' and does not further specify the conditions that represent 
an ``equivalent'' reduction in ozone. For instance, it does not require 
a specific concentration test at every monitor or at specific locations 
within an area. No such requirement appears in the CAA's other 
provisions governing the RFP demonstration, which define specific 
percentage reductions aimed at ensuring timely attainment of the NAAQS, 
or in the

[[Page 77772]]

EPA's 1993 NOX Substitution Guidance, which describes a 
recommended procedure for states to utilize NOX 
substitution.\9\ We interpret CAA section 182(c)(2)(C) and these 
supporting authorities as properly reflecting Congress's intent to 
allow NOX reductions to be considered within an RFP 
demonstration so long as these reductions are at least as effective as 
using VOC reductions in reducing ozone.
---------------------------------------------------------------------------

    \9\ EPA's NOX Substitution Guidance is posted in the 
docket for this rulemaking and at https://www3.epa.gov/ttn/naaqs/aqmguide/collection/cp2_old/19931201_oaqps_nox_substitution_guidance.pdf.
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B. Ozone Chemistry in the DFW Area

    The dynamics of ozone formation in the DFW area, including the 
proportion of VOC to NOX (``VOC: NOX ratio''), 
are described in Appendix D of the DFW Serious Area Attainment 
Demonstration SIP Revision for the 2008 Ozone NAAQS.\10\ Appendix D is 
the conceptual model for the DFW area, providing details on ozone 
transport, as well as trends and formation.
---------------------------------------------------------------------------

    \10\ Henceforth referred to as ``Appendix D'' and posted in the 
docket for this action.
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    The highest levels of ozone typically occur north and northwest of 
the Dallas urban core, e.g., at the Denton Airport South and Grapevine 
Fairway monitors -- these monitors are often downwind during the ozone 
season, as surface winds during this time are predominately from the 
south and southeast.\11\ The Grapevine Fairway monitor, northwest of 
the Dallas urban core, was the ``controlling'' monitor in 2018 and 
2020; the Dallas North monitor, north of the Dallas urban core, was the 
controlling monitor in 2019; and the Pilot Point monitor, north-
northwest of the Dallas urban core, was the controlling monitor in 
2021.\12\ The controlling monitor is the monitor with the highest ozone 
design value (DV) in the nonattainment area. The DV is the annual 
fourth highest daily maximum 8-hour average ozone concentration and is 
the metric to determine compliance with the 2008 ozone NAAQS. Thus, the 
controlling monitor determines the ozone DV for the nonattainment area.
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    \11\ A map showing the location of the 20 ozone monitors in the 
DFW area is posted in the docket for this action.
    \12\ The TCEQ posts the annual fourth highest daily maximum 8-
hour average ozone concentrations. See https://www.tceq.texas.gov/cgi-bin/compliance/monops/8hr_attainment.pl.
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    The DFW area is the fourth largest metropolitan area in the United 
States with about 7.5 million residents.\13\ Ozone precursor emissions 
(both NOX and VOC) in the DFW area and particularly the 
urban core of Dallas and Fort Worth have historically been dominated by 
mobile source emissions.\14\ In recent years however, only the 
NOX emissions in the DFW area are dominated by mobile 
sources and VOC emissions are dominated by area sources.\15\ Appendix D 
mentions that the highest average NOX concentrations have 
been measured at the Dallas Hinton Street ozone monitor, located in the 
Dallas urban core near several busy roadways. Monitors located to the 
south and southeast of Dallas County, in areas that are relatively 
rural, have measured the lowest NOX concentrations. 
NOX concentrations in the DFW area have declined since the 
mid-1980s and NOX concentrations at the Dallas Hinton Street 
monitor showed a 50 percent (%) decrease from 2003 through 2013. We 
believe that NOX emissions have continued to decrease since 
2013, as seen in the more recent and lower emission inventories for the 
DFW area cited earlier (81 FR 88124 and 87 FR 56891). Appendix D 
mentions that reductions in NOX concentrations outside the 
DFW urban core are not as large as those observed close to its center, 
which suggests that the measured decreases may be a result of 
reductions in NOX emissions from mobile sources. Decreases 
in VOC concentration have also been measured in the DFW area but are 
not as dramatic as the decreases in NOX emissions.
---------------------------------------------------------------------------

    \13\ U.S. Census Bureau, 2020 census data for the 10 counties 
comprising the DFW area. See https://www.census.gov/library/visualizations/interactive/2020-population-and-housing-state-data.html.
    \14\ For example, see the approved emission inventories at 73 FR 
58475 (October 7, 2008).
    \15\ See the emission inventories approved at 79 FR 67068 
(November 12, 2014), 81 FR 88124 (December 7, 2016), and 87 FR 56891 
(September 16, 2022).
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    The TCEQ uses analyses in Appendix D to conclude that monitors to 
the northwest and on the edges of the DFW area are transitional or 
NOX-limited, indicating that NOX controls would 
be more effective at controlling ozone in these areas. Monitors to the 
northwest include the Denton Airport South, Grapevine Fairway, Keller, 
and Eagle Mountain Lake, and monitors on the edges of the DFW area 
include Pilot Point, Parker County, Granbury, Cleburne Airport, Italy, 
Corsicana Airport, Kaufman, Rockwall Heath, and Greenville. Of these 
monitors, only the Grapevine Fairway, Pilot Point, and Cleburne Airport 
monitors had ozone DVs above 75 ppb from 2018 through 2021.
    Of the 20 ozone monitors in the DFW area, 15 have ozone DVs at or 
below 75 ppb from 2018 through 2021 and thus, are not relevant to the 
discussion on NOX substitution since these monitors are not 
violating the 2008 ozone NAAQS. Four of the five monitors with ozone 
DVs above 75 ppb (Frisco, Dallas North, Grapevine Fairway, and Pilot 
Point) are north and northwest (and typically downwind) from the Dallas 
urban core and thus, consistent with our earlier discussion on ozone 
chemistry and the TCEQ's analyses in Appendix D, we would expect 
NOX controls to be more effective than VOC controls for 
reducing ozone at these monitors. The fifth monitor with ozone DVs 
above 75 ppb is the Cleburne Airport monitor, which, as noted earlier, 
is on the edge of the DFW area and is south-southwest of the DFW urban 
core. While surface winds during the ozone season are predominately 
from the south and southeast, it is not unusual for surface winds to 
flow from the northeast (and thus, flow downwind from the DFW urban 
core) on days when the Cleburne Airport monitor exceeds the ozone 
standard.\16\ Therefore, consistent with our earlier discussion on 
ozone chemistry and the TCEQ's analyses in Appendix D, we would expect 
NOX controls to be more effective than VOC controls for 
controlling ozone at this monitor, too.
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    \16\ See the 2014-2016 back trajectory analyses from the 
Cleburne Airport monitor provided in the Dallas-Fort Worth and 
Houston-Galveston-Brazoria Nonattainment Areas Final Area 
Designations for the 2015 Ozone National Ambient Air Quality 
Standards Technical Support Document, Figure 6b on page 18. Figure 
6b shows winds predominantly from the northeast on days when the 
Cleburne Airport monitor exceeded the 2015 ozone NAAQS. This TSD is 
posted at https://www.regulations.gov/document/EPA-HQ-OAR-2017-0548-0403.
---------------------------------------------------------------------------

    A new analysis published by EPA authors looks at ozone formation 
regimes in 2007 and 2016 in ozone nonattainment areas, including the 
DFW area.\17\ Details for DFW are included in the supplemental 
information of that paper which suggests that: (1) day-of-week analysis 
points to the DFW area as a whole being NOX-limited in 2016 
but the controlling monitor being ``transitional,'' and (2) 
photochemical model sensitivity analysis (i.e., model predictions of 
how ozone will change with emissions perturbations) predicts that in 
2016 all locations in the DFW area were NOX-limited on 
average across days with ozone levels above 70 ppb (there could be some 
variability among those days). The controlling monitor in 2016 was the 
Denton Airport South monitor, northwest of the Dallas

[[Page 77773]]

urban core, with an ozone DV of 80 ppb.\18\
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    \17\ Reference: Koplitz, S; Simon, H; Henderson, B; Liljegren, 
J; Tonnesen, G; Whitehill, A; and Wells, B. Changes in Ozone 
Chemical Sensitivity in the United States from 2007 to 2016. ACS 
Environ. Au 2022, 2, 206-222. See also https://doi.org/10.1021/acsenvironau.1c00029. This article and the supplemental information 
are in the docket for this action.
    \18\ The ozone DV at the Denton Airport South monitor was at or 
below 75 ppb from 2018 through 2021.
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    An analysis of ozone and NOX for each day of the week 
for 1997-2013 is also provided in Appendix D. In the scientific 
literature, day-of-week analysis has been used to infer ozone chemical 
regimes.\19\ In many urban areas, NOX concentrations 
decrease on weekends while VOC concentrations remain fairly constant 
due to shifts in heavy-duty diesel vehicle patterns throughout the 
week. All other conditions being equal, if ozone concentrations 
decrease in parallel with these lower weekend NOX values 
that suggests a location has NOX-limited ozone formation 
regime. Conversely higher weekend ozone concentrations suggest a VOC-
limited ozone formation regime. The analysis presented in Appendix D 
finds that on Sundays, ozone and NOX concentrations were 
significantly lower compared to other days of the week and on Fridays, 
ozone and NOX concentrations were higher compared to other 
days of the week. Appendix D notes that the highest NOX 
concentrations (on Fridays) are also when traffic (on-road mobile 
source activity) is at its peak. Appendix D further presents site-level 
ozone concentrations by day-of-week and shows that the highest ozone 
concentrations occur mid-week at both an urban core site (Dallas Hinton 
Street) and at one of the controlling monitors (Grapevine Fairway) 
suggesting NOX-limited conditions in these locations. The 
analysis in Appendix D reviewed the number of days with ozone 
concentrations greater than 75 ppb (``high ozone days'') for each day 
of the week at all monitoring sites in the DFW area and found that 
fewer high ozone days occur on Sundays compared to other days of the 
week. Sunday had 85 high ozone days and Monday had the second lowest 
number of high ozone days--103. High ozone days occur most often on 
Fridays, with 137 days. While the day-of-week analysis is for years 
1997-2013, NOX reductions in the DFW area since 2013 are 
expected to result in more NOX-limited conditions than would 
have been present during the period of this analysis.
---------------------------------------------------------------------------

    \19\ Please see the list of references provided in the docket 
for this action.
---------------------------------------------------------------------------

    From 2018 through 2021, 15 of the 20 monitors in the DFW area 
recorded ozone DVs at or below 75 ppb and five monitors had ozone DVs 
above 75 ppb: Pilot Point, Grapevine Fairway, Dallas North, Frisco, and 
Cleburne Airport. The TCEQ's analyses in Appendix D indicate that 
NOX controls would be more effective at controlling ozone in 
these monitor locations. The TCEQ's findings here are consistent with 
our understanding of ozone chemistry and recent analysis of ozone 
formation regimes described earlier. Therefore, we find the TCEQ's use 
of NOX substitution in the DFW area reasonable, especially 
where the DFW monitors have DVs above 75 ppb from 2018 through 2021.

II. NOX Substitution in the TX RFP SIP for the DFW Area

    As described here and in our October 2020 proposal, the DFW serious 
nonattainment area for the 2008 ozone NAAQS had an attainment date of 
July 20, 2021.\20\ The attainment year ozone season is the ozone season 
immediately preceding a nonattainment area's maximum attainment date 
(see 40 CFR 51.1100(h)). Therefore, pursuant to CAA section 182(c)(2) 
and 40 CFR 51.1110, the RFP submittal for the DFW serious nonattainment 
area must demonstrate emissions reductions within the nonattainment 
area of three percent per year from January 1, 2018, to the end of the 
attainment year and thus, a nine percent reduction in emissions is 
required from January 1, 2018, through December 31, 2020. In addition, 
because the State has already satisfied the 15 percent VOC emissions 
reduction requirement for the DFW area,\21\ all 10 counties in the DFW 
Serious nonattainment area may substitute NOX reductions for 
VOC, consistent with the 2008 Ozone SRR (see 80 FR 12264, 12271), 40 
CFR 51.1110, and EPA's NOX Substitution Guidance.
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    \20\ See 84 FR 44238, (August 23, 2019). The EPA's final 
determination that the DFW area did not meet the July 20, 2021, 
attainment date for the 2008 ozone NAAQS is outside the scope of 
this action (see 87 FR 60926).
    \21\ See 81 FR 88124 (December 7, 2016).
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    The RFP submittal for the DFW area provides the required nine 
percent reductions as eight percent NOX emissions reductions 
and one percent VOC emissions reductions. As noted earlier, Appendix D 
describes the highest levels of NOX in the urban core and 
the highest concentrations of ozone recorded at monitors downwind of 
the urban core, predominantly in the north and northwest portions of 
the DFW area. Appendix D also describes a transitional regime in the 
DFW urban core and at the Eagle Mountain Lake monitor however, the 
monitors in the DFW urban core and the Eagle Mountain Lake monitor have 
ozone DVs at or below 75 ppb from 2018 through 2021 and thus, are not 
relevant to the discussion on NOX substitution. Appendix D 
also describes, consistent with EPA's discussion on ozone chemistry 
elsewhere in this action, that monitors to the north, northwest, and on 
the edges of the DFW area are transitional or NOX-limited. 
As mentioned earlier, four of the five monitors that recorded 
violations of the 2008 ozone NAAQS between 2018 and 2021 are north and 
northwest of the Dallas urban core: Pilot Point, Grapevine Fairway, 
Dallas North, and Frisco. The fifth monitor--the Cleburne Airport 
monitor--is on the south-southwest edge of the DFW area. Finally, the 
State's review of ozone and NOX for each day of the week 
links levels of NOX with ozone levels, indicating that 
decreasing levels of NOX would result in decreasing levels 
of ozone. Because ambient NOX and ozone data indicate those 
areas of DFW with the highest ozone values are NOX-limited, 
and because there are no violating monitors in the DFW areas described 
as VOC-limited, we agree with Texas that reductions in NOX 
are at least as effective in reducing ozone as VOC reductions. In 
addition, based on the EPA's analysis referenced earlier \22\ and the 
TCEQ's day-of-the-week analyses of NOX concentrations and 
ozone levels, we would also expect NOX reductions at the DFW 
urban core monitors to be at least as effective in reducing ozone as 
VOC reductions. Therefore, we find that the State's use of 
NOX substitution is warranted and appropriately implemented, 
and we propose to approve the NOX substitution provided in 
the RFP submittal for the DFW serious nonattainment area for the 2008 
ozone NAAQS.
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    \22\ Koplitz, S; Simon, H; Henderson, B; Liljegren, J; Tonnesen, 
G; Whitehill, A; and Wells, B. Changes in Ozone Chemical Sensitivity 
in the United States from 2007 to 2016. ACS Environ. Au 2022, 2, 
206-222. This article and the supplemental information are in the 
docket for this action.
---------------------------------------------------------------------------

III. Environmental Justice Considerations

    Executive Order 12898 (Federal Actions to Address Environmental 
Justice in Minority Populations and Low-Income Populations, 59 FR 7629, 
February 16, 1994) directs Federal agencies to identify and address 
``disproportionately high and adverse human health or environmental 
effects'' of their actions on minority populations and low-income 
populations to the greatest extent practicable and permitted by law. 
The EPA defines environmental justice (EJ) as ``the fair treatment and 
meaningful involvement of all people regardless of race, color, 
national origin, or income with respect to the development, 
implementation,

[[Page 77774]]

and enforcement of environmental laws, regulations, and policies.'' The 
EPA further defines the term fair treatment to mean that ``no group of 
people should bear a disproportionate burden of environmental harms and 
risks, including those resulting from the negative environmental 
consequences of industrial, governmental, and commercial operations or 
programs and policies.'' \23\ For this proposed action, the EPA 
conducted screening analyses using the EJScreen (Version 2.1) tool. We 
conducted the analyses for the purpose of providing information to the 
public, not as a basis of our proposed action. The EJScreen analysis 
reports are available in the docket for this rulemaking. The EPA found, 
based on the EJScreen analyses, that this proposed action will not have 
disproportionately high or adverse human health or environmental 
effects on communities with EJ concerns, as the RFP is an accounting of 
ozone precursor emission reductions throughout the 10-county DFW 
nonattainment area.
---------------------------------------------------------------------------

    \23\ See https://www.epa.gov/environmentaljustice/learn-about-environmental-justice.
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IV. Supplemental Proposed Action

    The EPA is supplementing our October 2020 proposal addressing 
revisions to the Texas SIP to meet the RFP requirements for the DFW 
serious nonattainment area for the 2008 ozone NAAQS. In this 
supplemental proposal, we are proposing to approve the substitution of 
NOX emission reductions for VOC emission reductions as 
consistent with section 182(c)(2)(C) of the CAA. The EPA is providing 
an opportunity for public comment on this supplemental proposal. 
However, we are not reopening for comment our October 2020 proposal. 
The EPA will address all comments received on our October 2020 proposal 
and on this supplemental proposal in our final action.

V. Statutory and Executive Order Reviews

    Under the CAA, the Administrator is required to approve a SIP 
submission that complies with the provisions of the Act and applicable 
Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in 
reviewing SIP submissions, the EPA's role is to approve state choices, 
provided that they meet the criteria of the CAA. Accordingly, this 
action merely proposes to approve state law as meeting Federal 
requirements and does not impose additional requirements beyond those 
imposed by state law. For that reason, this action:
     Is not a ``significant regulatory action'' subject to 
review by the Office of Management and Budget under Executive Orders 
12866 (58 FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 21, 
2011);
     Does not impose an information collection burden under the 
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
     Is certified as not having a significant economic impact 
on a substantial number of small entities under the Regulatory 
Flexibility Act (5 U.S.C. 601 et seq.);
     Does not contain any unfunded mandate or significantly or 
uniquely affect small governments, as described in the Unfunded 
Mandates Reform Act of 1995 (Pub. L. 104-4);
     Does not have federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Is not an economically significant regulatory action based 
on health or safety risks subject to Executive Order 13045 (62 FR 
19885, April 23, 1997);
     Is not a significant regulatory action subject to 
Executive Order 13211 (66 FR 28355, May 22, 2001);
     Is not subject to requirements of section 12(d) of the 
National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 
note) because application of those requirements would be inconsistent 
with the CAA; and
     Does not provide EPA with the discretionary authority to 
address, as appropriate, disproportionate human health or environmental 
effects, using practicable and legally permissible methods, under 
Executive Order 12898 (59 FR 7629, February 16, 1994).
    In addition, the SIP is not approved to apply on any Indian 
reservation land or in any other area where EPA or an Indian tribe has 
demonstrated that a tribe has jurisdiction. In those areas of Indian 
country, the proposed rule does not have tribal implications and will 
not impose substantial direct costs on tribal governments or preempt 
tribal law as specified by Executive Order 13175 (65 FR 67249, November 
9, 2000).

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Incorporation by 
reference, Nitrogen dioxide, Ozone, Volatile organic compounds.

    Authority: 42 U.S.C. 7401 et seq.

    Dated: December 15, 2022.
Earthea Nance,
Regional Administrator, Region 6.
[FR Doc. 2022-27603 Filed 12-19-22; 8:45 am]
BILLING CODE 6560-50-P
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