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SIP Revisions: DFW Moderate Classification Attainment and Reasonable Further Progress Demonstrations for the 2008 Eight-Hour Ozone Standard

Revisions to the Texas State Implementation Plan (SIP) developed for the Dallas–Fort Worth (DFW) 2008 eight-hour ozone standard moderate nonattainment area.

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.

Summary of the SIP Revisions

On March 12, 2008, the EPA strengthened the eight-hour ozone standard from 0.08 ppm to 0.075 ppm. Under the 0.075 ppm (75 parts per billion) standard, the EPA designated Collin, Dallas, Denton, Ellis, Johnson, Kaufman, Parker, Rockwall, Tarrant, and Wise Counties as nonattainment with a moderate classification, effective July 20, 2012. These counties form the DFW 2008 eight-hour ozone standard moderate nonattainment area. On June 3, 2015, the Texas Commission on Environmental Quality (TCEQ) adopted an attainment demonstration (AD) SIP revision and a Reasonable Further Progress (RFP) SIP revision for the DFW moderate nonattainment area under the 2008 eight-hour ozone National Ambient Air Quality Standard (NAAQS).

DFW AD SIP Revision for the 2008 Eight-Hour Ozone Standard (2013-015-SIP-NR)

Adoption Date: 06/03/2015
Proposal Date: 12/10/2014
EPA Action: Approved federal Clean Air Act (FCAA) Requirements for Vehicle Inspection and Maintenance and Nonattainment New Source Review on 6/14/2017 ( 82 FR 27122 ); Conditionally approved nitrogen oxides (NOX) reasonably available control technology (RACT) on 9/22/2017 ( 82 FR 44320 ); Approved volatile organic compounds (VOC) RACT on 12/21/2017 ( 82 FR 60546 )

Background: The FCAA requires states to submit plans to demonstrate attainment of the NAAQS for nonattainment areas within the state. On May 1, 2012, the 10-county DFW area, consisting of Collin, Dallas, Denton, Ellis, Johnson, Kaufman, Parker, Rockwall, Tarrant, and Wise Counties, was designated as a moderate nonattainment area for the 2008 eight-hour ozone standard. The attainment date for the DFW moderate nonattainment area was established in the United States Environmental Protection Agency’s (EPA) implementation rule for the 2008 ozone NAAQS published in the Federal Register (FR) on May 21, 2012 ( 77 FR 30160 ) and was set as December 31, 2018. Attainment of the standard (expressed as 0.075 parts per million) is achieved when an area’s design value does not exceed 75 parts per billion (ppb).

On December 23, 2014, the D.C. Circuit Court ruled on a lawsuit that modified the attainment date from December 31, 2018 to July 20, 2018. In addition, because the attainment year ozone season is the ozone season immediately preceding a nonattainment area’s attainment date, the attainment year for the DFW moderate nonattainment area changed from 2018 to 2017. Due to the timing of the court’s ruling and the EPA’s subsequent rulemaking action, it was not possible to complete all work necessary for this DFW AD SIP revision to demonstrate attainment in 2017. Therefore, this DFW AD SIP revision included the work completed to date to demonstrate that the DFW nonattainment area would attain the 2008 eight-hour ozone NAAQS by 2018 as proposed, and demonstrated progress toward attainment by the new 2017 attainment year. The DFW AD SIP revision also committed to develop a new AD SIP revision for the DFW 2008 eight-hour ozone nonattainment area as long as 2017 remains the attainment year.

Key Changes:

This SIP revision included:

  • Photochemical modeling and a weight of evidence analysis to demonstrate attainment by December 31, 2018;
  • Two rulemakings for RACT requirements for all control techniques guidelines (CTG) and all non-CTG major source emission source categories of VOC and NOX.
  • A contingency plan; and
  • A commitment to develop a new SIP revision to include an attainment demonstration, reasonably available control measures (RACM) analysis, and motor vehicle emissions budgets (MVEB) for the 2017 attainment year.

SIP Narrative and Appendices

This section contains downloadable documents containing the revisions to the SIP, including narratives, responses to comments, and appendices. Files linked from this page are in Portable Document Format (PDF).

Associated Rule Revisions

The commission adopted the following rule revisions for incorporation into the DFW AD SIP revision.

DFW RFP SIP Revision for the 2008 Eight-Hour Ozone Standard (2013-014-SIP-NR)

Adoption Date: 06/03/2015
Proposal Date: 12/10/2014
EPA Action: Approved 12/7/2016 ( 81 FR 88124 )

Background: The FCAA requires states to submit plans that demonstrate progress in reducing emissions for areas that are not attaining the NAAQS within their jurisdictions. On March 12, 2008, the EPA strengthened the eight-hour ozone standard from 0.08 ppm to 0.075 ppm. Under the 0.075 ppm (75 parts per billion) standard, the EPA designated Collin, Dallas, Denton, Ellis, Johnson, Kaufman, Parker, Rockwall, Tarrant, and Wise Counties as nonattainment with a moderate classification, effective July 20, 2012. These counties form the DFW 2008 eight-hour ozone standard moderate nonattainment area. The attainment date for the DFW moderate nonattainment area was established in the EPA’s implementation rule for the 2008 ozone NAAQS published in the Federal Register on May 21, 2012 ( 77 FR 30160 ) and was set as December 31, 2018. To fulfill FCAA requirements for moderate ozone nonattainment areas, the state is required to submit an RFP plan demonstrating that the DFW nonattainment area will reduce emissions of ozone precursors (VOC and NOX) consistent with moderate nonattainment area requirements. The DFW RFP SIP revision provides analyses of incremental reductions in NOx and VOC from a 2011 base year out to the attainment year for the 2008 eight-hour ozone standard.

On December 23, 2014, the D.C. Circuit Court ruled on a lawsuit that modified the attainment date from December 31, 2018 to July 20, 2018. In addition, because the attainment year ozone season is the ozone season immediately preceding a nonattainment area’s attainment date, the attainment year for the DFW moderate nonattainment area changed from 2018 to 2017. In order to address the change in the attainment year, the adopted SIP revision provides a required RFP analysis for the 2017 attainment year, including a contingency plan and MVEBs. This SIP revision also demonstrates an 18% emissions reduction in ozone precursors from the 2011 base year through a 2018 attainment year, a 3% emissions reduction demonstration for contingency for each milestone year, and updated RFP MVEBs for each milestone year, in the event that the 2018 attainment year requirement is reinstated.

Key Changes:

This SIP revision included:

  • An RFP analysis for both the originally proposed 2018 attainment year and the revised 2017 attainment year;
  • Updated 2011 base year emissions inventories for point, area, non-road mobile, and on-road mobile sources;
  • MVEBs for the revised 2017 attainment year as well as the originally proposed 2018 attainment year and 2017 milestone year; and
  • A contingency plan.

SIP Narrative and Appendices

This section contains downloadable documents containing the revisions to the SIP, including narratives, responses to comments, and appendices. Files linked from this page are in Portable Document Format (PDF).

Update: The 2017 Wise County RFP demonstration in the adopted DFW RFP SIP revision used a transfer of excess VOC reductions from the nine-county area previously designated as nonattainment to the newly designated Wise County. Upon notification that the option to transfer creditable VOC reductions between county groups was no longer available per the EPA's final 2008 Ozone Standard SIP Requirements Rule ( 80 FR 12264 ), the TCEQ corrected the adopted DFW RFP analyses to remove the VOC reduction transfer and credit emission reductions from drilling rig controls that were available but had not been credited. The corrections were submitted to the EPA in an April 22, 2016 technical supplement.

Contact Information and Updates

TCEQ: Get Information or Contact Staff

Dallas–Fort Worth: Contacts, Related Links

Dallas-Fort Worth: Latest Ozone Planning Activities