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Houston-Galveston-Brazoria: Ozone History

Background and history of Houston-Galveston-Brazoria (HGB) area compliance with the National Ambient Air Quality Standards (NAAQS) for ground-level ozone.

The SIP files on this page are hosted by the Texas Records and Information Locator (TRAIL) web archive . If you need assistance with a file, please contact siprules@tceq.texas.gov.

2015 Eight-Hour Ozone NAAQS (2015 to Present)

On October 1, 2015 the United States Environmental Protection Agency (EPA) revised the primary and secondary eight-hour ozone standards to 0.070 parts per million (ppm). The 2015 eight-hour ozone NAAQS became effective on December 28, 2015 ( 80 FR 65291 ). On June 4, 2018 the EPA designated a six-county HGB area including Brazoria, Chambers, Fort Bend, Galveston, Harris, and Montgomery Counties as marginal nonattainment for the 2015 eight-hour ozone NAAQS ( 83 FR 25776 ). Liberty and Waller Counties, which were designated nonattainment for the 2008 eight-hour ozone NAAQS, were not included in the HGB 2015 eight-hour ozone nonattainment area and were designated attainment (for more information, visit the State Ozone Designation Recommendation webpage). Under a marginal classification, the HGB area is required to attain the 2015 eight-hour ozone standard by the end of 2020 to meet an August 3, 2021 attainment date.

On June 10, 2020, the commission adopted the Emissions Inventory (EI) SIP Revision for the 2015 Eight-Hour Ozone NAAQS to satisfy the federal Clean Air Act (FCAA), §172(c)(3) and §182(a)(1) emissions inventory reporting requirements for nonattainment areas under the 2015 eight-hour ozone standard, including the HGB area. On June 29, 2021, the EPA published final approval of the EIs for the HGB, DFW, and Bexar County 2015 ozone nonattainment areas ( 86 FR 34139 ). On September 9, 2021, the EPA published final approval of the nonattainment new source review and emissions statement portions of this SIP revision ( 86 FR 50456 ).

The HGB nonattainment area did not meet the August 3, 2021 marginal attainment date. On April 13, 2022, the EPA proposed to reclassify the HGB nonattainment area from marginal to moderate for the 2015 eight-hour ozone NAAQS ( 87 FR 21842 ). On October 7, 2022, the EPA reclassified the six-county HGB area from marginal to moderate nonattainment, effective November 7, 2022 ( 87 FR 60897 ). The attainment date for the HGB moderate nonattainment area is August 3, 2024, with a 2023 attainment year.

2008 Eight-Hour Ozone NAAQS (2008 to Present)

On March 27, 2008, the EPA revised the primary and secondary eight-hour ozone NAAQS to 0.075 parts per million (ppm) ( 73 FR 16436 ). On March 10, 2009, the governor recommended to the EPA that only counties already designated nonattainment for the 1997 eight-hour ozone NAAQS (Brazoria, Chambers, Fort Bend, Galveston, Harris, Liberty, Montgomery, and Waller) be designated nonattainment for the 2008 eight-hour ozone NAAQS. (See the governor's 2009 designation recommendation letter ).

In September 2009, the EPA announced it would reconsider the 2008 ozone NAAQS. On January 19, 2009, the EPA proposed to lower the primary ozone NAAQS to a range of 0.060–0.070 ppm and proposed a separate secondary NAAQS based on cumulative seasonal average ozone concentrations. On September 2, 2011, President Obama announced that he had requested the EPA withdraw the proposed reconsidered ozone NAAQS.

In a September 22, 2011 memo from EPA Assistant Administrator Gina McCarthy , the EPA announced that it would proceed with initial area designations under the 2008 eight-hour ozone NAAQS, starting with the recommendations states made in 2009 and updating them with the most current, certified air quality data (2008 through 2010). On October 31, 2011, the governor sent a revised recommendation to the EPA that the same counties (Brazoria, Chambers, Fort Bend, Galveston, Harris, Liberty, Montgomery, and Waller) included in the March 10, 2009 governor’s recommendation be designated nonattainment for the 2008 eight-hour ozone NAAQS. (See the governor's 2011 revised designation recommendation letter ).

The EPA sent a letter to the governor on December 9, 2011 responding to the state's recommendations for area designations under the 2008 eight-hour ozone NAAQS (see the EPA's 2011 response to the revised recommendation ). In that letter, the EPA indicated that it intended to modify the state's recommended HGB nonattainment area designation to include Matagorda County.

On May 21, 2012, the EPA published final designations for the 2008 eight-hour ozone NAAQS in the Federal Register ( 77 FR 30088 ). An eight-county HGB area including Brazoria, Chambers, Fort Bend, Galveston, Harris, Liberty, Montgomery, and Waller Counties was designated nonattainment and classified marginal under the 2008 eight-hour ozone NAAQS effective July 20, 2012. The HGB area includes the same eight counties that were designated nonattainment under the 1997 eight-hour ozone NAAQS. Matagorda County was designated attainment/unclassifiable. As a result of the December 23, 2014 D.C. Circuit Court ruling and the EPA’s Implementation of the 2008 National Ambient Air Quality Standards for Ozone: State Implementation Plan Requirements; Final Rule (2008 ozone standard SIP requirements rule) published in the March 6, 2015 Federal Register ( 80 FR 12264 ), the attainment deadline is July 20, 2015 with a 2014 attainment year.

The HGB area did not attain the 2008 eight-hour ozone standard in 2014, but qualified for a one-year attainment date extension in accordance with federal Clean Air Act (FCAA), §181(a)(5). On February 27, 2015, the TCEQ submitted a one-year attainment date extension request to the EPA and on May 22, 2015, provided clarification regarding the TCEQ's certification that Texas meets the requirements of FCAA, §181(a)(5)(A). On May 4, 2016, the EPA approved a one-year attainment deadline extension for the HGB 2008 eight-hour ozone marginal nonattainment area to July 20, 2016 ( 81 FR 26697 ). Because the HGB area’s 2015 design value exceeded the 2008 eight-hour ozone NAAQS, the EPA published a final determination of nonattainment and reclassification of the HGB 2008 eight-hour ozone nonattainment area from marginal to moderate nonattainment on December 14, 2016 ( 81 FR 90207 ). The EPA set a January 1, 2017 deadline for the state to submit an attainment demonstration that addresses the 2008 eight-hour ozone NAAQS moderate nonattainment area requirements.

On December 15, 2016, the commission adopted the HGB 2008 Eight-Hour Ozone Attainment Demonstration and Reasonable Further Progress (RFP) SIP revisions to meet FCAA requirements for the 2008 eight-hour ozone NAAQS for a moderate nonattainment area with a July 20, 2018 attainment deadline and a 2017 attainment year. The AD SIP revision included a photochemical modeling analysis, a weight of evidence analysis, a reasonably available control technology analysis, a reasonably available control measures analysis, a motor vehicle emissions budget for 2017, and a contingency plan. The AD SIP revision incorporated revisions to 30 Texas Administrative Code Chapter 115 to update reasonably available control technology (RACT) for volatile organic compounds (VOC) storage tanks in the HGB area. The RFP SIP revision included an analysis of reasonable further progress toward attainment of the 2008 eight-hour ozone standard, which demonstrated a 15% emissions reduction in ozone precursors from the 2011 base year through the 2017 attainment year and a 3% emissions reduction for contingency in 2018, and included updated RFP motor vehicle emissions budgets (MVEBs). The SIP and rule revisions were submitted to the EPA on December 29, 2016. On May 15, 2017, the EPA approved Section 4.9 of the attainment demonstration SIP revision that describes how FCAA requirements for vehicle inspection and maintenance, nonattainment new source review, and emission statements for large stationary point sources are met in the HGB area for the 2008 ozone NAAQS ( 82 FR 22291 ). On June 6, 2017, the EPA published its finding that the MVEBs in the HGB RFP SIP are adequate and must be used for transportation conformity determinations in the HGB area ( 82 FR 26091 ).

On February 16, 2018, the United States Court of Appeals for the District of Columbia Circuit issued an opinion in the case South Coast Air Quality Management District vs. EPA, 882 F.3d 1138 (D.C. Cir. 2018) . The court's decision vacated parts of the EPA's final 2008 eight-hour ozone standard SIP requirements rule, including the redesignation substitute, removal of anti-backsliding requirements for areas designated nonattainment under the 1997 eight-hour ozone NAAQS, waiving requirements for transportation conformity for maintenance areas under the 1997 eight-hour ozone NAAQS, and elimination of the requirement to submit a second 10-year maintenance plan. In response to the ruling, the commission adopted the HGB Redesignation Request and Maintenance Plan for the One-Hour and 1997 Eight-Hour Ozone Standards SIP Revision on December 12, 2018. See the 1997 Eight-Hour Ozone Standard and the One-Hour Ozone Standard sections below for more information.

On August 23, 2019, the EPA reclassified the eight-county HGB nonattainment area from moderate to serious for the 2008 eight-hour ozone NAAQS ( 84 FR 44238 ). The attainment date for serious nonattainment areas is July 20, 2021 with a 2020 attainment year. On March 4, 2020, the commission adopted the HGB Serious Classification Attainment Demonstration SIP Revision for the 2008 Eight-Hour Ozone NAAQS and the DFW and HGB RFP SIP Revision for the 2008 Eight-Hour Ozone Standard. The SIP revisions were submitted to the EPA on May 13, 2020. Serious classification attainment demonstration and RFP SIP revisions were due to the EPA by August 3, 2020. On September 29, 2020, the EPA published proposed approval of the serious classification RFP SIP revision for the HGB nonattainment area ( 85 FR 60928 ). On May 10, 2021, the EPA published partial final approval of the serious classification RFP SIP revision for the HGB nonattainment area ( 86 FR 24717 ). This action did not finalize the proposed approval of the portion of the SIP that addresses contingency measure requirements for the 2008 eight-hour ozone NAAQS.

On June 30, 2021, the commission adopted Chapter 115 VOC RACT Rules to address the EPA’s 2016 Oil and Natural Gas Industry Control Technique Guidelines (CTG) for the HGB 2008 eight-hour ozone nonattainment area.

On March 25, 2021, the TCEQ submitted the 2008 Eight-Hour Ozone NAAQS Milestone Compliance Demonstration for the 2020 Calendar Year for the HGB serious nonattainment area. The EPA responded with a letter of adequacy on July 1, 2021.

The HGB nonattainment area did not meet the July 20, 2021, serious area attainment date, but it did meet the qualifications for a one year attainment date extension. On April 5, 2021, the TCEQ submitted a one-year attainment date extension request to the EPA for the HGB 2008 eight-hour ozone nonattainment area.

On April 13, 2022, the EPA proposed to reclassify the HGB nonattainment area from serious to severe for the 2008 ozone standard ( 87 FR 21825 ). On October 7, 2022, the EPA reclassified the eight-county HGB area from serious to severe nonattainment, effective November 7, 2022 ( 87 FR 60926 ). As a part of this final action, the EPA denied the one-year attainment date extension request citing air quality trends and environmental justice concerns. The attainment date for the HGB severe nonattainment area is July 20, 2027, with a 2026 attainment year.

1997 Eight-Hour Ozone NAAQS (1997 to Present)

Note: The HGB area (Brazoria, Chambers, Fort Bend, Galveston, Harris, Liberty, Montgomery, and Waller Counties) is currently classified severe nonattainment for the 1997 eight-hour ozone NAAQS, with an attainment deadline of June 15, 2019.

On July 18, 1997, the EPA published the revised NAAQS for ground-level ozone in the Federal Register ( 62 FR 38856 ), and it became effective on September 16, 1997. The EPA phased out and replaced the previous one-hour ozone NAAQS with an eight-hour NAAQS set at 0.08 ppm based on the three-year average of the annual fourth-highest daily maximum eight-hour average ozone concentrations measured at each monitor within an area.

Effective June 15, 2004, Brazoria, Chambers, Fort Bend, Galveston, Harris, Liberty, Montgomery, and Waller Counties were designated nonattainment in the first phase of the EPA's implementation rule for the 1997 eight-hour ozone NAAQS ( 69 FR 23951 ). The HGB area was classified moderate nonattainment for the standard, with an attainment deadline of June 15, 2010. The TCEQ was required to submit a SIP revision for the 1997 eight-hour ozone NAAQS to the EPA by June 15, 2007. The EPA addressed the control obligations that apply to areas designated nonattainment for the 1997 eight-hour ozone NAAQS in the second phase of the implementation rule ( 70 FR 71612 ).

The commission adopted the 2007 HGB 1997 Eight-Hour Ozone Nonattainment Area SIP revision on May 23, 2007 as the first step in addressing the 1997 eight-hour ozone NAAQS in the HGB area. The revision included additional Voluntary Mobile Source Emissions Reduction Program (VMEP) commitments, a RACT analysis, and the Texas 2002 Periodic Emissions Inventory for the HGB ozone nonattainment area. The SIP revision also incorporated amendments to 30 Texas Administrative Code (TAC) Chapter 114, relating to the Texas low emission diesel (TxLED) rule for certain marine fuels and 30 TAC Chapter 115, relating to the control VOC emissions from storage and degassing operations in the HGB area. On April 2, 2013, the EPA published approval of portions of the RACT analysis for certain VOC and nitrogen oxides (NOX) categories and the VMEP commitments (applicable through 2009) ( 78 FR 19599 ). On April 15, 2014 and March 27, 2015, the EPA published approval of the RACT analysis for the remaining source categories that were not previously approved as meeting RACT requirements ( 79 FR 21144  and 80 FR 16291 ).

The commission also adopted the 2007 HGB 1997 Eight-Hour Ozone Nonattainment Area Reasonable Further Progress (RFP) SIP revision on May 23, 2007, which demonstrated that a required 15% emissions reduction in ozone precursors (VOC and NOX) would be met for the 2001 through 2008 RFP analysis period. On April 22, 2009, the EPA published approval of this SIP revision, the associated motor vehicle emission budgets (MVEB), and the 2002 base year emissions inventory ( 74 FR 18298 ).

On June 15, 2007, the state requested that the HGB area be reclassified from a moderate to a severe nonattainment area for the 1997 eight-hour ozone NAAQS, with an attainment deadline of June 15, 2019. (See the governor's 2007 reclassification request letter ).

On December 31, 2007, the EPA published its proposal to grant the governor's request and took comments on a range of dates for the state to submit a revised SIP ( 72 FR 74252 ). The TCEQ provided comments to the EPA that supported the reclassification and justification for an April 2010 SIP submission date. (See the TCEQ's comments concerning the EPA's proposed redesignation ).

On October 1, 2008, the EPA published approval of the governor's request to voluntarily reclassify the HGB ozone nonattainment area from a moderate to a severe nonattainment area for the 1997 ozone NAAQS ( 73 FR 56983 ) effective October 31, 2008. The EPA set April 15, 2010 as the date for the state to submit a revised SIP addressing the severe-ozone nonattainment requirements. The HGB area's new attainment deadline for the 1997 ozone NAAQS is as expeditious as practicable but no later than June 15, 2019.

On March 10, 2010, the commission adopted two revisions to the Texas SIP for the HGB ozone nonattainment area. The 2010 HGB Attainment Demonstration SIP Revision for the 1997 Eight-Hour Ozone Standard included a photochemical modeling analysis and a weight of evidence analysis to demonstrate attainment of the 1997 eight-hour ozone NAAQS by the June 15, 2019 deadline. This SIP revision also included MVEBs, VOC and NOX RACT analyses, Reasonably Available Control Measures (RACM) analysis, contingency plan, and a mid-course review commitment. In addition, this SIP revision incorporated revisions to 30 TAC Chapters 101 and 115, also adopted on March 10, 2010, which include the Mass Emissions Cap and Trade (MECT) Program Cap Integrity, the Highly Reactive Volatile Organic Compounds (HRVOC) Emissions Cap and Trade (HECT) Program Cap Reduction and Allowance Reallocation, and the VOC Control Techniques Guidelines (CTG) Update for offset lithographic printing. On April 2, 2013, April 15, 2014, and August 4, 2014, the EPA published its approvals of the RACT analysis for NOX and certain VOC CTG categories in this SIP revision ( 78 FR 19599 , 79 FR 21144 , and 79 FR 45105 ). On March 27, 2015, the EPA published the remaining source categories not previously approved as meeting RACT requirements ( 80 FR 16291 ). On January 2, 2014, the EPA published its approval of this attainment demonstration SIP revision and revisions to the MECT and HECT programs ( 79 FR 57 ).

The 2010 HGB RFP SIP Revision for the 1997 Eight-Hour Ozone Standard , as required by the EPA, demonstrated that an 18% emissions reduction requirement will be met for the 2002 through 2008 RFP analysis period and that an average of 3% per year emissions reduction will occur between each of the milestone years 2008, 2011, 2014, 2017, and 2018. This SIP revision established baseline emission levels, calculated reduction targets, identified control strategies to meet emission target levels, and tracked actual emission reductions against established emissions growth. This revision also included an MVEB for each milestone year and a contingency plan. On January 25, 2011, the EPA published a notice of its determination that the MVEBs in the March 10, 2010 SIP revisions, which were developed using the on-road mobile source emissions inventories based on the EPA's MOBILE 6.2 model, were adequate for transportation conformity purposes ( 76 FR 4342 ). On January 2, 2014, the EPA published approval of this RFP SIP revision ( 79 FR 51 ).

On December 7, 2011, the commission adopted the 2011 HGB RACT Analysis Update SIP Revision for the 1997 Eight-Hour Ozone Standard . This SIP revision updated the RACT analysis for VOC emission sources to include the seven CTG documents issued by the EPA from 2006 through 2008 that were not addressed in the 2010 HGB Attainment Demonstration SIP revision. This SIP revision incorporated concurrent CTG-related rulemaking that revises Chapter 115, Subchapter E to implement RACT for those CTG emission source categories in the HGB area. On March 27, 2015, the EPA published approval of this SIP update ( 80 FR 16291 ).

On April 23, 2013, the commission adopted the 2013 HGB 1997 Eight-Hour Ozone Standard Nonattainment Area MVEB Update SIP Revision . This SIP revision updated on-road mobile source emissions inventories and MVEBs for the HGB area using the EPA's latest mobile emissions estimation model, the Motor Vehicle Emissions Simulator (MOVES2010a). This SIP revision also met the primary obligation of the mid-course review commitment in the 2010 HGB attainment demonstration SIP revision by demonstrating that the outstanding 3% contingency requirement was fulfilled. Updated on-road inventories and emissions analysis based on the EPA’s August 30, 2012 vehicle miles traveled offset guidance and a modified version of the MOVES model demonstrated compliance with FCAA requirements for transportation control measures in severe nonattainment areas. On January 2, 2014, the EPA published approval of this MVEB SIP update to the 2010 attainment demonstration SIP revision ( 79 FR 57 ).

The EPA published a final determination of attainment for the 1997 eight-hour ozone standard for the HGB area in the December 30, 2015 Federal Register ( 80 FR 81466 ).

On August 18, 2015, the TCEQ submitted the Redesignation Substitute Report for the HGB 1997 Eight-Hour Ozone Standard Nonattainment Area to the EPA. This report fulfills the EPA’s redesignation substitute requirements in its 2008 ozone standard SIP requirements rule to lift anti-backsliding obligations for the revoked 1997 eight-hour ozone NAAQS by ensuring that specific redesignation requirements are met under the revoked standard. This redesignation substitute would take the place of a redesignation request and maintenance plan, which the EPA would require for a standard that has not been revoked. According to EPA’s 2008 ozone standard SIP requirements rule, this report is based on certain FCAA redesignation criteria and includes: monitoring data showing attainment of the revoked 1997 eight-hour ozone NAAQS; a showing that attainment was due to permanent and enforceable emissions reductions; and a demonstration that the area can maintain the standard through 2028 via emissions inventory trends and future emission projections. The EPA published final approval of the redesignation substitute report on November 8, 2016 ( 81 FR 78691 ) with an effective date of December 8, 2016.

On April 27, 2016, the commission adopted the HGB Area Redesignation Substitute SIP Revision for the 1997 Eight-Hour Ozone NAAQS (Non-Rule Project No. 2015-001-SIP-NR).

On December 14, 2018, the TCEQ submitted the HGB Redesignation Request and Maintenance Plan for the One-Hour and 1997 Eight-Hour Ozone Standards SIP Revision to the EPA which includes a request that the HGB area be formally redesignated to attainment for the 1997 eight-hour ozone NAAQS. On May 16, 2019, the EPA proposed: a determination that the HGB area has met redesignation criteria and is continuing to attain the 1997 eight-hour ozone NAAQS; termination of the antibacksliding obligations; and approval of the maintenance plan ( 84 FR 22093 ).

On December 12, 2018, the commission adopted the HGB Redesignation Request and Maintenance Plan for the One-Hour and 1997 Eight-Hour Ozone Standards SIP Revision  in response to the South Coast Air Quality Management District vs. EPA 882 F.3d 1138 (D.C. Cir. 2018) ruling. The SIP revision was submitted to the EPA on December 14, 2018 and includes a request that the HGB area be formally redesignated to attainment for the 1997 eight-hour ozone NAAQS. On May 16, 2019, the EPA proposed: a determination that the HGB area has met redesignation criteria and is continuing to attain the one-hour and 1997 eight-hour ozone NAAQS; termination of the anti-backsliding obligations; and approval of the maintenance plan ( 84 FR 22093 ). On February 14, 2020, the EPA published final action on the SIP revision ( 85 FR 8411 ). The final rule terminates all anti-backsliding obligations for the HGB area for the 1997 eight-hour ozone NAAQS and approves the maintenance plan. The action did not redesignate the area to attainment, because the EPA has taken the position that it lacks the authority to redesignate areas to attainment under revoked standards.

One-Hour Ozone NAAQS

Note: In 1997, the one-hour ozone NAAQS was replaced by the more protective eight-hour ozone NAAQS. Although the EPA revoked the one-hour ozone NAAQS in June 2005, some former one-hour ozone nonattainment areas have continuing obligations to comply with the anti-backsliding requirements described in 40 Code of Federal Regulations §51.905(a).

In 1990, the eight-county HGB one-hour ozone nonattainment area was classified as severe according to the FCAA. At that time, the FCAA also required submission of a SIP revision describing actions to be taken to reduce NOX and VOC by November 1996. Before that deadline, however, modeling showed uncertainties in the actual impact that NOX reductions would have on ground-level ozone formation. The HGB area was therefore granted a temporary exemption until December 1997 to fulfill its NOX attainment requirements, after which the HGB area was given a new attainment deadline of November 15, 2007.

The 2000 HGB One-Hour Ozone Attainment Demonstration SIP revision was adopted on December 6, 2000 with a November 15, 2007 attainment date. The attainment demonstration contained numerous air pollution control measures. A 2001 Follow-Up HGB Attainment Demonstration SIP revision was adopted in September 2001 that incorporated revisions to several control strategies. On November 14, 2001, the EPA published approval of these SIP revisions (66 FR 57159 ).

The commission incorporated additional revisions with the 2002 One-Hour Ozone Attainment Demonstration SIP revision , which was adopted on December 13, 2002. These revisions addressed: (1) the agreements contained in the consent order arising from the litigation with the Business Coalition for Clean Air Appeal Group and several industrial companies and (2) the incorporation of energy efficiency measures and the protocol for the Texas Emissions Reduction Plan.

On October 27, 2004, the commission adopted the 2004 HGB One-Hour Ozone Post 1999 Rate-of-Progress (ROP) SIP revision . This revision updated the emissions inventories, ROP budgets, and MVEBs for the area. On February 14, 2005, the EPA published approval of this SIP revision ( 70 FR 7407 ).

On December 1, 2004, the commission adopted the 2004 HGB One-Hour Ozone Attainment Demonstration Mid-Course Review SIP revision , reflecting a strategy based on reducing NOX and point source HRVOC rather than NOX alone. This revision contained results of photochemical modeling and technical documentation in support of the one-hour ozone attainment demonstration by November 15, 2007. The revision changed a number of NOX control strategies and added the HRVOC emission reduction requirements. On September 6, 2006, the EPA published approval of the HGB area’s one-hour ozone attainment demonstration and associated rules ( 71 FR 52656 ). The approval was published in six parts, covering the rules for the control of HRVOC, the one-hour ozone attainment plan, the HECT Program for HRVOC, the MECT Program for NOX, the Emissions Credit Banking and Trading program, and the Discrete Emissions Credit Banking and Trading program.

On June 19, 2012, the EPA published a final determination that the HGB area failed to attain the one-hour ozone NAAQS by its November 15, 2007 attainment deadline ( 77 FR 36400 ). Although the EPA revoked the one-hour ozone NAAQS, states must continue to meet two one-hour ozone anti-backsliding requirements that are triggered by a finding of failure to attain by the applicable attainment date: contingency measures and FCAA, §185 major stationary source fee programs. Reductions from contingency measures have already been achieved in the HGB area, and a final determination of failure to attain does not trigger additional emission reductions. However, a final determination of failure to attain by the area's one-hour attainment date triggers the one-hour anti-backsliding obligation to implement the penalty fee program under FCAA, §182(d)(3) and §185, unless that obligation is terminated. On May 22, 2013, the commission adopted rules under 30 TAC Chapter 101, Subchapter B to implement these FCAA provisions. .

On July 22, 2014, the TCEQ submitted a Redesignation Substitute Report for the HGB One-Hour Ozone Standard Nonattainment Area to the EPA. This report fulfills the EPA’s redesignation substitute requirements in its 2008 ozone standard SIP requirements rule ( 78 FR 34178 ) to lift anti-backsliding obligations for the revoked one-hour ozone NAAQS by ensuring that specific redesignation requirements are met for the HGB area under the revoked standard. This redesignation substitute would take the place of a redesignation request and maintenance plan, which the EPA would require for a standard that has not been revoked. According to the EPA’s 2008 ozone standard SIP requirements rule, this report is based on certain FCAA redesignation criteria and includes: monitoring data showing attainment of the revoked one-hour ozone NAAQS; a showing that attainment was due to permanent and enforceable emissions reductions; and a demonstration that the area can maintain the standard through 2026 via emissions inventory trends and future emission projections. The EPA published final approval of the redesignation substitute report on October 20, 2015 ( 80 FR 63429 ).

On July 1, 2015, the commission adopted the HGB Redesignation Substitute SIP Revision for the One-Hour Ozone NAAQS (Non-Rule Project No. 2014-011-SIP-NR).

On December 14, 2018, the TCEQ submitted the HGB Redesignation Request and Maintenance Plan for the One-Hour and 1997 Eight-Hour Ozone Standards SIP Revision to the EPA in response to the South Coast Air Quality Management District vs. EPA, 882 F.3d 1138 (D.C. Cir. 2018) ruling. The SIP revision includes a request that the HGB area be formally redesignated to attainment for the one-hour ozone NAAQS. On February 14, 2020, the EPA published final action on the SIP revision ( 85 FR 8411 ). The final rule terminates all anti-backsliding obligations for the HGB area for the one-hour ozone NAAQS and approves the maintenance plan. The action did not redesignate the area to attainment, because the EPA has taken the position that it lacks the authority to redesignate areas to attainment under revoked standards. 

Comprehensive History of the Texas SIP

This SIP History gives a broad overview of the SIP revisions that have been submitted to the EPA by the State of Texas. Some sections may be obsolete or superseded by new revisions but have been retained for the sake of historical completeness.