Geothermal
- Geothermal Authority
- Closed-Loop Geothermal Wells for Heating or Cooling
- Injection Wells for Geothermal Energy
Authority
The Railroad Commission (RRC) regulates the exploration, development, and production of geothermal energy and associated resources on public and private land for the purpose of conservation and the protection of correlative rights. Injection wells used for the production of geothermal or geopressured water and their by-products must be permitted by the RRC prior to beginning injection.
As of September 1, 2023, in accordance with Senate Bill 786 of the 88th Legislature, all geothermal wells are under the jurisdiction of the Commission, including closed-loop geothermal wells that use the earth as a heat sink to heat or cool a structure. All rules, standards and forms used by the Texas Commission on Environmental Quality (TCEQ) to regulate closed-loop geothermal wells remain in effect until altered by RRC. TCEQ will transfer any pending closed-loop geothermal well permit applications to RRC by September 1, 2023. As applicable, RRC will issue substitute permits for any closed-loop geothermal wells currently permitted by TCEQ by December 1, 2023.
Closed-Loop Geothermal Wells Used for Heating or Cooling
RRC’s regulation of closed-loop geothermal wells is the same as TCEQ’s regulation (rules, standards and forms) until RRC amends those rules or adopts new rules. RRC does not plan to change the rules, standards or forms at this time. TCEQ’s Underground Injection Control (UIC) Class V rules, which includes closed-loop geothermal wells, can be found in Title 30, Texas Admin. Code (TAC), Chapter 331, Subchapter H (“Standards for Class V Wells”).
Summary of Closed-loop Geothermal Well Rules
- Authorization: Closed-loop geothermal wells are authorized by rule unless requested to submit an application for a permit. For example, a well owner or operator may be required to submit an application for a permit if the well is not in compliance with the Standards for Class V Wells.
- Licensed Driller: Closed-loop geothermal wells must be drilled and completed by a water well driller licensed in Texas.
- Completion:
- Annulus:
- The annular space of a closed-loop geothermal well shall be backfilled to the total depth with impervious bentonite or a similar material.
- Where no groundwater or only one zone of groundwater is encountered, sand, gravel, or drill cuttings may be used to backfill up to 30 feet from the surface. The top 30 feet shall be filled with impervious bentonite.
- Comminglingly Prohibited: Closed-loop geothermal wells shall be completed so that aquifers or zones containing waters that are known to differ significantly in chemical quality are not allowed to commingle through the borehole-casing annulus and cause degradation of any freshwater aquifer. The well must be constructed so that there is no significant movement of fluids into any underground source of drinking water.
- Surface Completion:
- If the well is completed with casing at or above grade: The slab or block shall extend at least two feet from the well in all directions and have a minimum thickness of four inches and shall be separated from the well casing by a plastic or mastic coating or sleeve to prevent bonding of the slab to the casing. The surface of the slab shall be sloped so that liquid will drain away from the well.
- Closed loop injection wells which are completed below grade are exempt from surface completion standards. Pitless adapters may be used in wells provided that: the adapter is welded to the casing or fitted with another suitably effective seal, and the annular space between the borehole and the casing is filled with cement to a depth not less than 15 feet below the adapter connection.
- Annulus:
- Completion Report and Working Fluid: The water well driller must submit a copy of the Texas Department of Licensing and Regulation Well Report Form to RRC within 30 days of well completion. Any additives, constituents, or fluids (other than potable water) that are used in the closed loop injection well system shall be reported in the Water Quality Section on the state well report form.
- Plugging:
- It is the responsibility of the owner or operator to close a closed-loop geothermal well which is to be permanently discontinued or abandoned. Closure shall be accomplished by removing all of the removable casing and the entire well shall be pressure filled via a tremie pipe with cement from bottom to the land surface.
- If the well is not completed through zones containing undesirable groundwater, water that is injurious to human health and the environment or water that can cause pollution to land or other waters, the well may be filled with fine sand, clay, or heavy mud followed by a cement plug extending from land surface to a depth of not less than ten feet below the land surface.
- If the well is completed through zones containing undesirable groundwater, water that is injurious to human health and the environment or water that can cause pollution to land or other waters, either the zone(s) containing undesirable groundwater or the fresh groundwater zone(s) shall be isolated with cement plugs and the remainder of the wellbore filled with bentonite grout (9.1 pounds per gallon mud or more) followed by a cement plug extending from land surface to a depth of not less than ten feet below the land surface.
Injection Wells for Geothermal Energy
If you are planning a geothermal energy project in Texas, it is recommended that you discuss with Injection-Storage Permits Unit staff before submitting an application to permit an injection well for your project. You can email us at UIC@rrc.texas.gov.
Rules
An applicant for an injection well permit to produce geothermal energy and associated resources will be required to submit information typical of injection/disposal well applications and information addressing the specific nature of the proposed operation. The applicant must abide by all applicable RRC rules. Oil and Gas Division rules regarding administration, oil and gas well construction and operation, and injection wells (for example, 16 TAC §3.1, 3.13, 3.14 and 3.46) are generally applicable to a geothermal injection well unless specifically stated otherwise.
Confidentiality
If you believe that any of the information requested below is confidential, contact the Injection-Storage Permits Unit Manager or Office of General Counsel prior to submitting any potentially confidential information. Permit applications are Open Records under the Texas Public Information Act (Texas Government Code, Chapter 552).
Geothermal Energy Operator Requirements
- You must have an active Form P-5, Organization Report.
- You must be the Form P-4 (leaseholder) of an on-schedule well.
Geothermal Energy Production Well Forms
- Form W-1 (Application to Drill, Deepen or Reenter)
- Form W-2/G-1 (Completion Report) in the online Completion Report system
- Form GT-1 (Geothermal Production Test, Completion or Recompletion Report, and Log)
- Form GT-1 should be attached to the Completion Report packet in the online system.
- Form GT-2 (Producer's Monthly Report of Geothermal Wells)
Geothermal Energy Injection Well Permit Application
- Form GT-5 (Application to Inject Fluid into a Reservoir Productive of Geothermal Resources)
- Note: Form GT-5 does not include a space for Operator Number or Field Number. Please include those numbers and other reference information on the forms where applicable.
- Form H-1A (Injection Well Data for H-1 Application)
- Provide all the applicable information required by the Forms required above with applicable fees and surcharges, including fees for exceptions if applicable.
- All injectate components and sources
- Safety Data Sheets for chemicals
Common Attachments
- Provide all the attachments typically required to be submitted with the Forms H-1/H-1A, including:
- Well Log
- Groundwater Letter (Form GW-2)
- AOR (1/4 mile)
- Include water well survey in AOR
- Historic Seismicity data across AOI (9.08 km radius), including
- Perpendicular cross-sections with formations and zones annotated
- Structure maps on top and bottom of proposed zone(s)
- Isopach map of proposed zone(s)
- A map and accompanying list showing the names, address and locations of adjacent landowners within one-half mile of the proposed geothermal well or facility; the location of water wells within one mile of the proposed geothermal well or facility; the names, addresses and locations of operators within ½ mile of the proposed geothermal well or facility.
- Proof of notice of application
- Published Notice
- Notice of application to all Operators within one-half mile
- Notice of application to all adjacent surface owners
- Freshwater Injection questionnaire & Form H-7 (Fresh Water Data Form), if applicable.
- Provide detailed information on why freshwater must be used for injection and how much will be used, including water quality analysis.
Injection Well Construction
- Provide information regarding compatibility of the casing and the injectate. All casing materials shall be suitable for the proposed operating design stresses and temperatures.
- Provide a well diagram.
- Detailing the size, type, depth of casing strings and cement behind the casing strings.
- How Usable-Quality Water (UQW, ≤ 3,000 ppm TDS) will be protected.
- How Underground Sources of Drinking Water (USDW, ≤ 10,000 ppm TDS) will be protected.
- Whether the completion is open hole or cased.
- If tubing and packer or surface casing is not used, provide an:
- Explanation as to why tubing and packer or surface casing cannot be used
- Explanation of how safety and protection of natural resources will be maintained without typical well construction
- Explanation of how the mechanical integrity of the well will be determined without tubing and packer
Injection Well Completion
- Provide a description of the planned completion program for the well, including:
- The proposed well treatment, acid job, hydraulic fracture, etc.
- Proposed monitoring during completion.
Injection Operations
- Provide a discussion of injection purpose and procedures.
- Provide a surface facility diagram with purpose, dimensions and capacities of storage.
- See pit permitting information on the Pits webpage.
- Provide a proposed Maximum Surface Injection Pressure (MSIP) or procedure for determining the MSIP. For example: “A Step-Rate Test (SRT) will be performed to determine fracture pressure of the reservoir. The Maximum Surface Injection Pressure (MSIP) will be no greater than 90% of the fracture pressure. The proposed MSIP will be submitted to the Commission within 10 days of completion of the SRT.”
- Provide a description of the expected lifetime of the facility and conditions for closure.
- Provide a description of proposed Facility closure procedures.
Injection Monitoring
- Mechanical Integrity Test (MIT)
- Initial MIT must be performed before injection and the results filed on Form H-5 (Online)
- Annual MIT must be performed
- The operator must provide a description of the MIT procedure, which should include, at a minimum:
- Initial and annual annulus pressure tests, and
- The results of a temperature or noise log.
- The wellhead must have all gauges required by rule. Provide a description of the gauges you will have on the wellhead and your procedures for monitoring well head pressure.
- Provide a description of the methods, procedures, and frequency for injectate water quality testing, and frequency of reporting to the Commission.
- Well testing and logging data required within 30 days:
- An electric log as defined by SWR 16 from surface
- Cement Bond Log (CBL)
Injection Reporting
- The operator must file an online completion packet (Form W-2/G-1) within 30 days of completion
- Form H-10 (Annual Disposal/Injection Well Monitoring Report)