Permitting options and guidance relating to oil and gas sites that handle or produce ‘sour’ gas.
While the regulation of oil and gas activities in Texas falls primarily under the jurisdiction of the Railroad Commission of Texas (RRC), TCEQ regulates air emissions resulting from these activities. Of specific focus in this webpage are hydrogen sulfide (H2S) emissions from oil and natural gas handling and production sites. Owners and operators of these sites must obtain a TCEQ air authorization.
Operations related to oil and gas wells are designated as sweet or sour depending on the concentration of H2S. The RRC’s Statewide Rule 36 imposes certain additional requirements when the concentration of H2S is equal to or greater than 100 parts per million (ppm). [Title 16 Texas Administrative Code Section 3.36 (16 TAC 3.36)
TCEQ designates operations as sour if the concentration of H2S contains more than 1.5 grains per 100 cubic feet, or more than 30 grains of total sulfur per 100 cubic feet. This quantity is the equivalent of approximately 24 ppm, well below the 100 ppm RRC threshold. [30 TAC 101.1(96)
While a site may be below the RRC's H2S threshold, it could still meet the TCEQ threshold. If the concentration of H2S at a site meets or exceeds TCEQ’s definition of sour, the operations are subject to increased regulatory requirements.
It is the owner or operator’s responsibility to ensure that each site complies with all applicable regulations and apply the 24 ppm level to their determinations for sour gas compliance with TCEQ.
As oil and gas wells age, the H2S levels of fields where they are located may increase. To ensure ongoing compliance, owners and operators are strongly encouraged to periodically review the current H2S concentration representations to determine if sites are keeping sour gas below the 24 ppm H2S threshold.
While there are numerous methods to demonstrate if a site is not handling sour gas, TCEQ encourages sites that have a H2S gas analysis greater than two years to perform a H2S concentration gas analysis of the product to ensure compliance under the proper authorization. If your site is handling or producing sour gas per the TCEQ definition, you will be subject to increased regulatory requirements, dependent on the site’s specific type of air permit.
TCEQ has developed a tiered approach to provide more options for permitting oil and gas facilities that include: de minimis exclusion; historical authorization; permits by rule; standard permits; and case-by-case (New Source Review) permits.
Determine if your site is authorized under the De Minimis rule.
Find out if your site qualifies for a historical authorization for existing, unchanged oil and gas sites.
Certain oil and gas handling and processing facilities may be eligible for coverage under the Permit by Rule in 30 TAC 106.352
if they are not authorized under the de minimis rule or a historical standard exemption.
Facilities located outside the Barnett Shale counties and that are handling sour gas are required to meet the following:
Facilities located within counties in the Barnett Shale (Cooke, Dallas, Denton, Ellis, Erath, Hill, Hood, Jack, Johnson, Montague, Palo Pinto, Parker, Somervell, Tarrant, and Wise) are required to comply with the requirements of 30 TAC 106.352 subparts (a-k) of the Permit By Rule.
Find additional guidance information on this PBR at TCEQ's Air PBR 106.352 webpage.
Depending on the operating scenario, other PBRs may be applicable to the facility.
If facilities cannot meet the requirements in the Permit by Rule, they may be eligible for coverage under the Standard Permit in 30 TAC 116.620
. The Standard Permit has additional requirements for facilities with fugitive emissions or using field gas for combustion, if the gas is sour.
H2S fugitive emissions are prohibited unless the equipment is inspected and repaired as per subsection (c)(3) of the standard permit. [30 TAC 116.620(a)(11)]
H2S fugitive emissions are prohibited unless the equipment is inspected and repaired as per subsection (c)(3) of the standard permit OR
H2S emissions are monitored with ambient property line monitors as per subsection (e)(1) of the standard permit. [30 TAC 116.620(a)(11)]
Exception: If a flare is the only combustion unit on a property, the operator is not required to maintain such records on flare pilot gas.
Find additional guidance information on this Standard Permit at the Standard Permit for Oil and Gas webpage.
Facilities within the Barnett Shale constructed or modified after April 1, 2011, are subject to the requirements of subsections a-k of this permit. Requirements specific to the handling of sour gas are:
All new projects and dependent facilities not located in the Barnett Shale counties are subject to subsection l of this permit and are held to the requirements of Standard Permit 116.620. For projects located outside the Barnett Shale counties which are constructed or modified on or after April 1, 2011, companies may voluntarily register under the new requirements in (a)-(k).
Find additional guidance on the Non-Rule Standard Permit on the Standard Permit for Oil and Gas webpage.
If a facility cannot meet the requirements of the Permit by Rule or the Standard permits, then they must authorize their site using one of the other available individual or “case-by-case” air permits. You can find information on these permits and their applications at the New Source Review Application Tools webpage.
The Texas Environmental, Health and Safety Audit Privilege Act (Audit Act) may be helpful to certain facilities that are unsure of their compliance status. The Audit Act provides certain immunities from administrative or civil penalties for violations voluntarily disclosed and corrected within a reasonable amount of time. Learn more about the
Find more information and compliance resources at the TCEQ Oil and Gas Activities webpage. If you have questions about air authorizations or the definition of sour gas within TCEQ regulations, please contact the Small Business and Local Government Assistance section at (800) 447-2827 or the Air Permits Division at (512) 239-1250 . You can also email any questions about these issues to TexasEnviroHelp@tceq.texas.gov.