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Dallas-Fort Worth Ozone Nonattainment Area
This page introduces Dallas–Fort Worth’s air quality challenges, air quality plan, and control strategies. It also contains links to rules, agreements, State Implementation Plan (SIP) revisions, and other documents that relate to the Dallas–Fort Worth area.


Counties: Collin, Dallas, Denton, Tarrant, Ellis, Johnson, Kaufman, Parker, Rockwall
Ozone Standard Designation: 9 counties, Moderate Nonattainment, June 2010 ( 69 FR 23858 Exit the TCEQ)
Attainment Deadline: June 15, 2010
Emissions Inventory: 2002
Fact Sheet: Dallas/Fort Worth SIP Revision


The 1990 Clean Air Act Amendments authorized the U.S. Environmental Protection Agency to designate areas failing to meet the National Ambient Air Quality Standard for ozone as nonattainment and to classify them according to severity. The DFW area was classified as a “moderate” nonattainment area and was required to demonstrate attainment by November 15, 1996. A SIP was submitted with controls focused almost entirely on volatile organic compounds, but the DFW area did not attain the standard by the mandated deadline. Consequently, in 1998 the EPA reclassified the DFW area from “moderate” to “serious,” resulting in a new attainment deadline of November 15, 1999.

The DFW area also failed to reach attainment by the November 1999 deadline. In the attainment demonstration SIP adopted by the TCEQ in April 2000, the importance of local nitrogen oxides (NOx) reductions as well as the transport of ozone and its precursors from the Houston-Galveston-Brazoria (HGB) area were taken into account. Based on photochemical modeling demonstrating that transport from the HGB area was impacting DFW’s air quality, the TCEQ requested an extension of the DFW attainment date to November 15, 2007, the same attainment date as for the HGB area.

Unlike the industrialized HGB and Beaumont–Port Arthur areas, where industrial point sources account for about half of the total NOx for each area, point source NOx in DFW is about one-eighth of the total inventory. The majority of NOx in the DFW area comes from onroad mobile (cars and trucks) and nonroad mobile (construction equipment, aircraft, locomotives, among others) sources.

As the result of a number of suits filed against the EPA in 2002, the courts ruled that the EPA does not have authority under the Clean Air Act to extend an area’s attainment date based on transport from another ozone nonattainment area. Although the DFW area was not the specific subject of any of these suits, by extension of the court’s basis for decision the DFW one-hour ozone attainment demonstration SIP cannot be approved by the EPA. Phase I of the EPA’s eight-hour Implementation published in the federal register on April 30, 2004 gave areas without an approved one-hour ozone attainment plan the option to submit a one-hour ozone attainment demonstration no later than one year after designation (by June 15, 2005); submit an eight-hour ozone plan no later than one year after designation (by June 15, 2005) that provides a 5 percent increment of progress from the area’s 2002 emissions baseline that are in addition to federal measures and state measures already approved by EPA, and to achieve these reductions by June 15, 2007; or submit an eight-hour ozone attainment demonstration by June 15, 2005. The TCEQ chose to meet the second option, which represented the best path forward for the DFW area at the time.

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Recent Activities

Last updated: 03/31/06

The following DFW SIP Modeling Sensitivities can be found at the Dallas-Fort Worth Ozone SIP Modeling Webpage:

Cement Kiln Sensitivity Results

East Texas Combustion/Engine Sensitivity Results

Major Source Sensitivity Results — includes Electric Generating Facilities and Industrial, Commercial, & Institutional (ICI) Sources

NCTCOG Proposed Onroad & Non-Road Sensitivity Resultscontrols proposed by the North Central Texas Council of Governments (NCTCOG) to onroad and non-road emissions

Map of DFW 9-County Major Sources (in PDF)  — includes Cement Kilns, Electric Generating Facilities and the top ten Industrial, Commercial, & Institutional (ICI) Sources.

The Dallas–Fort Worth 5 Percent Increment of Progress (IOP) SIP was adopted by the commission on April 27, 2005. Also on this date, the commission adopted several rules that support the DFW 5 Percent IOP SIP. These rules include new emission standards for lean-burn and rich-burn engines, an extension of existing requirements for both surface coating and Stage I gasoline unloading to the five newly designated counties, and a statewide portable fuel container rule.

Upcoming Activities

On August 8 the Commission will hold two public hearings to receive testimony concerning proposed revisions to 30 TAC Chapter 115, Control of Air Pollution from Volatile Organic Compounds.  The proposed amendments to §§115.10, 115.119, 115.129, 115.139, 115.149, 115.219, 115.239, 115.319, 115.359, 115.419, 115.439, 115.449, 115.519, and 115.539 would subject owners or operators of certain VOC-emitting facilities located in Ellis, Johnson, Kaufman, Parker, and Rockwall Counties to the same control, monitoring, testing, recordkeeping, and reporting requirements to which owners or operators of facilities in the other four counties in the DFW nonattainment area are subject.

Two public hearings on this proposal will be held on August 8, 2006, at 2:30 p.m. and 6:30 p.m. at the Waxahachie City Hall Council Chambers located at 401 S. Rogers in Waxahachie, TX .

The hearings will be structured for the receipt of oral or written comments by interested persons. There will be no open discussion during the hearings; however, commission staff members will be available to informally discuss the proposal 30 minutes before each hearing.

TCEQ continues to develop photochemical modeling and control strategies for an eight-hour ozone attainment demonstration. The DFW Attainment Demonstration SIP Revision Time Line lists TCEQ activities related to the DFW 8-hour ozone attainment demonstration.

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Potential Control Strategies in DFW

Potential Control Strategies to Consider for the Dallas-Fort Worth 8-Hour Ozone Attainment Demonstration

The TCEQ is considering a wide variety of point source, area source, nonroad mobile, and onroad mobile control strategies to implement in order to attain the 8-hour ozone standard in the Dallas-Fort Worth area.

The following rule concepts are being developed to potentially support the DFW 8-hour ozone SIP. Please note that these rule concepts do not necessarily represent all of the rules and control strategies that may be required to attain the 8-hour ozone standard:

2006-012-117-EN NOx RACT for Point Source and Utilities
2006-011-115-EN VOC RACT Update
2006-006-117-EN East Texas Combustion Sources
2006-005-117-EN DFW Minor Source Rule
2006-004-117-EN DFW Cement Kiln Rule
2006-003-117-EN DFW NOx Major Source and Utility Controls for Attainment Demonstration
2006-002-117-EN East Texas Electric Generating Facility Rules

Track the progress of these rule concepts

Interested parties are encouraged to provide constructive feedback to the TCEQ regarding the strategies listed and to provide potential strategies for consideration that are not currently included in the control strategies catalog. Comments and suggestions may be submitted to Please type "DFW Control Strategies" in the subject line in order to ensure proper delivery of your e-mail.

The TCEQ is also working in conjunction with the North Central Texas Council of Governments (NCTCOG) to develop an additional control strategy catalog for the Dallas-Fort Worth area. For more information on NCTCOG's efforts, please visit their website . Please check this web page periodically for further updates to the control strategies catalog documents.

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DFW Eight-Hour SIP & Rules Stakeholder Group

The DFW Eight-Hour SIP & Rules Stakeholder Group is an open-participation group that will meet to discuss concepts of potential rules for the 9-county DFW ozone nonattainment area in Title 30, Texas Administrative Code, Chapter 115 and Chapter 117 and to hear the public’s ideas on potential rulemaking concepts and the development of Texas’ clean air plan. Many of the links on this page point to files posted in Portable Document Format (PDF) Format. Help with PDF.

Agendas of Upcoming Meetings

Future DFW Eight-Hour SIP & Rules Stakeholder Group meeting notices will be posted here. Please check back for updates to this web page or join our list-serv for e-mail updates.

Previous Meetings

Meetings of the DFW Eight-Hour SIP & Rules Stakeholder Group were held on June 20 & 21, 2006, in the City of Irving City Council Chambers located at 825 W Irving Blvd. Individual rule concepts were discussed at the following times:

TCEQ Staff Presentations

North Central Texas Council of Governments (NCTCOG) Presentation

Meeting Summary

Informal Stakeholder Comments

Al Armendariz, Ph.D.

Jim Schermbeck


DFW Stakeholders

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Air Quality Plans

The links below take you to a listing of all air quality plans in Texas, including plans that pertain to the Dallas–Fort Worth area.

Contact Information

You can receive updates regarding stakeholder meetings, alerts about revisions to the SIP, requests for comments, and other SIP-related news items by joining our e-mail list. To join, send a blank e-mail to: with no subject or message. (NOTE: The alert list does not receive e-mails.)

For more information, please contact:

Tom Lawshae, DFW SIP Coordinator at 512/239-3181

Kelly Keel, SIP Team Leader at 512/239-3607

Ashley Forbes, Rule Development Team Leader at 512/239-0493.

Designated Air Quality Planning Groups

North Texas Clean Air Coalition (NTCAC)
P. O. Box 610246, DFW Airport, TX 75261-0246
Phone: 972/621-0400

North Central Texas Council of Governments (NCTCOG)
616 Six Flags Drive, Suite 200, Arlington, TX 76005-5888
Phone: 817/640-3300

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