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Air Emissions and Maintenance Events

Air Emissions Events and Maintenance, Startup, and Shutdown Activities regulated under 30 TAC Chapter 101

Certain incidents that result in unauthorized emissions are required to be recorded or reported to TCEQ. The types of included events are emissions events; scheduled maintenance, startup, and shutdown (MSS) activities; and excess opacity events as defined in 30 TAC Chapter 101 Subchapter F. With the goals of efficiency and consistency, the TCEQ created the Emissions Event Review Section on September 01, 2022, which was tasked with reviewing and investigating all air emissions and maintenance events reported in the State of Texas.

For more information about STEERS, reporting requirements, or to search for incidents reported to TCEQ, you can visit Reports of Air Emissions Events.

When an emissions event occurs, Air Emissions and Maintenance Events (AEME) notifications and reports are required to be submitted via STEERS, the State of Texas Environmental Electronic Reporting System (STEERS). The initial notification must be submitted within 24 hours of discovery if a reportable quantity will be exceeded. A final report must be entered into STEERS two weeks (14 days) from the end date and time of the event.

STEERS notification and reporting is not required for small businesses that meet the small business definition in Texas Water Code Section 5.135(g)(2). Small businesses shall provide notifications and reporting by any viable means that meet the time frames required by 30 TAC Chapter 101. Small businesses should email the notification or report to EE@tceq.texas.gov.

In the event that STEERS is unavailable due to mechanical failures or scheduled maintenance or you are a small business, required reporting under 30 Texas Administrative Code (TAC) Chapter 101 (e.g. emissions event, opacity event, and maintenance, startup, & shutdown activity) may be completed by emailing the form below to EE@tceq.texas.gov.  If you are not a small business, emailing the form to the Emissions Event Review Section only allows you to meet the reporting deadline. Once STEERS is available you must submit the required notification or report in STEERS.

If you encounter issues with the STEERS operating system, your user account or password, or have questions about scheduled system maintenance:

You can also consult the STEERS Air Emissions and Maintenance Events (AEME) Help page for assistance with entering events into STEERS.

Additional guidance specific to oil and gas facilities can be reviewed on the Small Business and Local Government Assistance's Oil and Gas Facilities: Air Compliance Information webpage.

Upset events that are determined not to be excessive emissions events are subject to an affirmative defense to all claims in enforcement actions brought for these events, other than claims for administrative technical orders and actions for injunctive relief.

NOTE:The affirmative defenses found in 30 TAC 101.222 do not apply to excessive emissions events or federally promulgated performance or technology-based standards and you may still be assessed a violation even if AD was determined to be met.

After receiving the initial notification from STEERS, TCEQ conducts an initial screening of the incident based on criteria located in the Texas Administrative Code. This review is to determine if the event was avoidable and assess whether or not operators took measures to minimize emissions.

Once TCEQ receives a final report for a reportable emissions event, the Emission Events Review Section will email questions to the company contact, to ask for additional information. If you claim an affirmative defense, you will be given 30 days to respond to the questions. If an affirmative defense is not claimed, there will be fewer questions and you will be given one week to respond.

After the responses are received, an investigator will review the information to determine if the event meets the criteria for an excessive emissions event and, if not, whether the company has met the affirmative defense requirements (if claimed). The investigator may email additional follow-up questions to the company contact. If no violations are cited, or if it is determined that the incident was not a reportable emissions event, a closure letter will be sent to the company.

If the investigator determines that a Notice of Violation (NOV) should be issued, the owner/operator or regulated entity (regulated entity) will be notified by email. Following receipt of the NOV, the regulated entity will need to provide information that demonstrates compliance or a date when the violation(s) will be resolved. Compliance must be achieved within 30 days from the date of the NOV. If compliance is not achieved within the 30-day timeframe, a Notice of Enforcement (NOE) may be issued, and the incident will be referred to the TCEQ Enforcement Division.

If the investigator determines that the incident necessitates a NOE and an affirmative defense claim was made, a Notice of Preliminary Findings (NOPF) letter will first be emailed to the regulated entity. The regulated entity may provide any additional information addressing the violation(s) at that time or request a meeting to discuss the alleged violation(s) within 5 days. Reasonable requests for additional time will be evaluated on a case-by-case basis. Based on the response or lack thereof, either a NOE or a closure letter will be provided to the company.

If an affirmative defense is not claimed, a similar NOV or NOE process is followed as described above. However, no NOPF letter is transmitted.

If an affirmative defense is claimed but it is determined that not all applicable criteria have been met, the NOV or NOE will identify which criteria were not met.

For more information on penalty assessment and enforcement, review the current Enforcement Initiation Criteria.

The TCEQ reviews all reported incidents to determine if they meet the criteria for an excessive emissions event (EEE). The criteria are listed in 30 TAC § 101.222(a)(1)-(6). If the agency determines that one or more of the six criteria have been met, the incident may be considered excessive. In general, emissions events that cause significant impact to human health or the environment may be determined to be excessive. Examples include onsite or offsite impacts, but are not limited to:

  • injuries requiring treatment at a medical facility,
  • documented health impacts (e.g., in a physician’s report or an investigator’s recorded experience),
  • a fatality, or
  • wildlife, domesticated animals, or vegetative impacts.

When reviewing the frequency of the incidents under 30 TAC § 101.222(a)(1), the evaluation is based on incidents that occurred at the specific facility under review; this includes incidents that affect the whole site (i.e., incidents that impacted more than just the specific facility under review).

When reviewing the cause of the emissions event under 30 TAC § 101.222(a)(2), the investigator will evaluate whether the event could have been foreseen. Examples of events that could have been foreseen may include, but are not limited to, operator error (including third party contractors), not protecting equipment from the elements and wildlife, and preventable accidents.

The third criterion, 30 TAC § 101.222(a)(3), concerns quantity and impact of the emissions event on human health or the environment. If the event was of a large enough magnitude that an Air Monitoring Comparison Value (AMCV), Effects Screening Level (ESL), NAAQS, or PSD increment might have been exceeded, the owner/operator will likely be requested to conduct dispersion modeling of the event. The modeling results will be reviewed in coordination with the agency’s Air Permits and Toxicology Divisions.

When reviewing the duration of the emissions event, under criteria 30 TAC § 101.222(a)(4) and (5), the investigator will evaluate the duration and percentage of the specific emissions event in relation to that facility’s annual operating hours.

For the final criterion, 30 TAC § 101.222(a)(6), the investigator will review the provided information to determine whether there was a need for a startup, shutdown, or maintenance activity, which could have helped to reduce or eliminate the emissions associated with the event.

  • (Q) Why can't I enter my final excess opacity report in STEERS?
    • (A)Excess opacity events only have an initial notification, so your initial notification IS your final report. STEERS will not allow you to submit a final report for an excess opacity event. TCEQ will reach out to you for additional information after receiving your initial notification and you can include any revisions to your initial notification in your response.
  • (Q)The event that I reported in STEERS ended up not exceeding a reportable quantity and I would like it revoked or deleted.
    • (A)Initial notifications, once submitted in STEERS cannot be revoked, deleted, or retracted. Please note that no reportable quantity was exceed on your Final Report in STEERS. If you have already submitted your Final Report, include that information in your response to the affirmative defense questions.
  • (Q) Why can't I see my incident in STEERS or on the external search?
    • (A) This means your incident is not verified in STEERS and is considered to be DRAFT. You will need to verify the incident in order for it to be "live" and visible.
  • (Q) Why can't I see my initial notification in STEERS and submit my final report?
    • (A) The incident is visible on the external search. You will need to contact EE@tceq.texas.gov since the incident may have already been assigned to a pending investigation and the status in our system is "CLOSED". Closed incidents are not visible in STEERS.
  • (Q) I am receiving a STEERS error message that my account is in probationary status, but have verified with STEERS Help Line that it is active, what is wrong?
    • (A) The error could be caused by the incident being in "CLOSED" status due to being associated to an investigation. Contact EE@tceq.texas.gov for assistance.
  • (Q) How do I update information on my STEERS account?
  • UPDATE Victoria County is no longer maintenance for ozone standards, so the reportable quantity for NOx is 5,000 pounds.