Exceptional Event Demonstrations for Particulate Matter
Demonstrations supporting the proposed exceptional events for particulate matter data.
About Exceptional Events
Definition
Exceptional events are unusual or naturally occurring events that affect air quality and are not reasonably controllable or preventable. Wildfires, prescribed fires, high winds blowing dust, dust from the Sahara Desert, fireworks to celebrate days such as July 4th, etc., can be considered exceptional events.
How They Affect Monitoring Data
States can request that the United States Environmental Protection Agency (EPA) exclude air quality monitoring data affected by an exceptional event from determining if an area met an air quality health standard . This page provides access to exceptional event demonstration documents developed by TCEQ.
EPA Regulations and Guidance
Exceptional event regulations and guidance are provided on EPA's Treatment of Air Quality Data Influenced by Exceptional Events website.
Draft Exceptional Event Proposals
2022 Atascosa, Hidalgo, Nueces, Tarrant, and Webb Counties
- Demonstration Summary (English)
- Demonstration Summary (Spanish)
- Proposed 2022 PM2.5 Exceptional Event at Atascosa, Hidalgo, Nueces, Tarrant, and Webb Counties Demonstration Report (English Only)
- Appendix A: Weather Maps and Graphs (English Only)
- Appendix B: NWS Discussions and Forecasts (English Only)
- Appendix C: Media Reports and TCEQ Forecasts (English Only)
- Appendix D: Initial Notification and Flagging (English Only)
Public Comment Period: August 5, 2025 – September 5, 2025
TCEQ is posting this demonstration for written public comment on August 5, 2025. For your comment to be submitted to the EPA along with the final demonstration, it must be e-mailed by 5:00 p.m. CDT on September 5, 2025, or it must be postmarked by September 5, 2025.
Submit comments on the demonstration to amda@tceq.texas.gov, with the subject line “2022 PM2.5 Exceptional Events Demonstration - Atascosa, Hidalgo, Nueces, Tarrant, and Webb Counties” or mail the comments to:
TCEQ Air Modeling and Data Analysis Section
MC 164
P.O. Box 13087
Austin, TX 78711-3087.
2023 Atascosa, Hidalgo, Tarrant, and Webb Counties
- Demonstration Summary (English)
- Demonstration Summary (Spanish)
- Proposed 2023 PM2.5 Exceptional Event at Atascosa, Hidalgo, Tarrant, and Webb Counties Demonstration Report (English Only)
- Appendix A: Weather Maps and Graphs (English Only)
- Appendix B: NWS Discussions and Forecasts (English Only)
- Appendix C: Media Reports and TCEQ Forecasts (English Only)
- Appendix D: Initial Notification and Flagging (English Only)
Public Comment Period: August 5, 2025 – September 5, 2025
TCEQ is posting this demonstration for written public comment on August 5, 2025. For your comment to be submitted to the EPA along with the final demonstration, it must be e-mailed by 5:00 p.m. CDT on September 5, 2025, or it must be postmarked by September 5, 2025.
Submit comments on the demonstration to amda@tceq.texas.gov, with the subject line “2023 PM2.5 Exceptional Events Demonstration - Atascosa, Hidalgo, Tarrant, and Webb Counties” or mail the comments to:
TCEQ Air Modeling and Data Analysis Section
MC 164
P.O. Box 13087
Austin, TX 78711-3087.
2024 Atascosa, Hidalgo, Nueces, Tarrant, and Webb Counties
- Demonstration Summary (English)
- Demonstration Summary (Spanish)
- Proposed 2024 PM2.5 Exceptional Event at Atascosa, Hidalgo, Nueces, Tarrant, and Webb Counties Demonstration Report (English Only)
- Appendix A: Weather Maps and Graphs (English Only)
- Appendix B: NWS Discussions and Forecasts (English Only)
- Appendix C: Media Reports and TCEQ Forecasts (English Only)
- Appendix D: Initial Notification and Flagging (English Only)
Public Comment Period: August 5, 2025 – September 5, 2025
TCEQ is posting this demonstration for written public comment on August 5, 2025. For your comment to be submitted to the EPA along with the final demonstration, it must be e-mailed by 5:00 p.m. CDT on September 5, 2025, or it must be postmarked by September 5, 2025.
Submit comments on the demonstration to amda@tceq.texas.gov, with the subject line “2024 PM2.5 Exceptional Events Demonstration - Atascosa, Hidalgo, Nueces, Tarrant, and Webb Counties” or mail the comments to:
TCEQ Air Modeling and Data Analysis Section
MC 164
P.O. Box 13087
Austin, TX 78711-3087.
2022, 2023, and 2024 Harrison, Kleberg and Travis Counties
- Demonstration Summary (English)
- Demonstration Summary (Spanish)
- Proposed 2022, 2023, and 2024 PM2.5 Exceptional Event at Harrison, Kleberg, and Travis Counties Demonstration Report (English Only)
- Appendix A: Weather Maps and Graphs (English Only)
- Appendix B: NWS Discussions and Forecasts (English Only)
- Appendix C: Media Reports and TCEQ Forecasts (English Only)
- Appendix D: Initial Notification and Flagging (English Only)
Public Comment Period: August 5, 2025 – September 5, 2025
TCEQ is posting this demonstration for written public comment on August 5, 2025. For your comment to be submitted to the EPA along with the final demonstration, it must be e-mailed by 5:00 p.m. CDT on September 5, 2025, or it must be postmarked by September 5, 2025.
Submit comments on the demonstration to amda@tceq.texas.gov, with the subject line “2022, 2023, and 2024 PM2.5 Exceptional Events Demonstration - Harrison, Kleberg and Travis Counties” or mail the comments to:
TCEQ Air Modeling and Data Analysis Section
MC 164
P.O. Box 13087
Austin, TX 78711-3087.
2022, 2023, and 2024 Jefferson County
- Demonstration Summary (English)
- Demonstration Summary (Spanish)
- Proposed 2022, 2023, and 2024 PM2.5 Exceptional Event at Jefferson County Demonstration Report (English Only)
- Appendix A: Weather Maps and Graphs (English Only)
- Appendix B: NWS Discussions and Forecasts (English Only)
- Appendix C: Media Reports and TCEQ Forecasts (English Only)
- Appendix D: Initial Notification and Flagging (English Only)
Public Comment Period: August 5, 2025 – September 5, 2025
TCEQ is posting this demonstration for written public comment on August 5, 2025. For your comment to be submitted to the EPA along with the final demonstration, it must be e-mailed by 5:00 p.m. CDT on September 5, 2025, or it must be postmarked by September 5, 2025.
Submit comments on the demonstration to amda@tceq.texas.gov, with the subject line “2022, 2023, and 2024 PM2.5 Exceptional Events Demonstration - Jefferson County” or mail the comments to:
TCEQ Air Modeling and Data Analysis Section
MC 164
P.O. Box 13087
Austin, TX 78711-3087.
2023 and 2024 El Paso County
- Demonstration Summary (English)
- Demonstration Summary (Spanish)
- Proposed 2023 and 2024 PM2.5 Exceptional Event at El Paso County Demonstration Report (English Only)
- Appendix A: Weather Maps and Graphs (English Only)
- Appendix B: NWS Discussions and Forecasts (English Only)
- Appendix C: Media Reports and TCEQ Forecasts (English Only)
- Appendix D: Initial Notification and Flagging (English Only)
Public Comment Period: August 5, 2025 – September 5, 2025
TCEQ is posting this demonstration for written public comment on August 5, 2025. For your comment to be submitted to the EPA along with the final demonstration, it must be e-mailed by 5:00 p.m. CDT on September 5, 2025, or it must be postmarked by September 5, 2025.
Submit comments on the demonstration to amda@tceq.texas.gov, with the subject line “2023 and 2024 PM2.5 Exceptional Events Demonstration - El Paso County” or mail the comments to:
TCEQ Air Modeling and Data Analysis Section
MC 164
P.O. Box 13087
Austin, TX 78711-3087.
Finalized Exceptional Event Demonstrations (Submitted to EPA)
El Paso, Nueces, and Harris County PM10 Demonstration for Three Days in 2021
- Demonstration Summary (English)
- Demonstration Summary (Spanish)
- Final PM10 Exceptional Event Demonstration Report (English only)
- Public Comments Received from June 27, 2023 to July 31, 2023 (English only)
- 9/12/2023 Letter to EPA Submitting Demonstration (English only)
El Paso Demonstrations
December 23, 2020 PM10 Exceptional Event
- Demonstration Summary (English)
- Demonstration Summary (Spanish)
- Final PM10 Exceptional Event Demonstration Report (English only)
- Public Comments Received from October 26, 2022 to December 2, 2022 (English only)
- 1/2/2023 Letter to EPA Submitting Demonstration (English only)
2017-2018 PM10 Exceptional Events
- Final 2017-2018 Exceptional Events Demonstration (English Only)
2010-2012 PM2.5 and PM10 Exceptional Events
- Final 2010-2012 Exceptional Events Demonstration (English Only)
- Addendum (English Only)
Houston Clinton Monitor Demonstrations (English Only)
2012 Exceptional Events
2011 Exceptional Events
2010 Exceptional Events
Related Topics
- Ozone Exceptional Event Demonstrations
- Mitigation Plans for Exceptional Events in Texas
- EPA Review of TCEQ Mitigation Plans
- International transport demonstrations to Texas nonattainment areas
- TCEQ Index of Air Topics lists a wide range of programs and how the agency is working to improve air quality in Texas