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Class V Injection Wells Regulated by the TCEQ

Class V injection wells are used to inject nonhazardous fluids into or above formations that contain underground sources of drinking water. This page includes instructions, guidance documents, and authorization/inventory forms for new or amended authorizations/inventories to construct, convert, modify, operate Class V Injection wells.

Contact the TCEQ UIC Permits staff if you have any questions or would like to schedule a meeting.

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Types of Class V Injection Wells

A well is a bored, drilled, or driven shaft whose depth is greater than the largest surface dimension, a dug hole whose depth is greater than the largest surface dimension, an improved sinkhole, or a subsurface fluid distribution system. A well does not include any surface pit, surface excavation, or natural depression. Injection wells are wells into which any material or substance which flows or moves whether in a semisolid, liquid, gas or any other form or state are injected. Class V wells are injection wells that are not included in Classes I, II, III, IV or VI.

Air conditioning return flow wells in an open loop system used to return groundwater used for heating or cooling in a heat pump to the supply aquifer

Aquifer recharge wells used to replenish the water in an aquifer or for storage and subsequent retrieval for beneficial use as part of an aquifer storage and recovery project

Aquifer remediation wells, temporary injection points, and subsurface fluid distribution systems used to inject nonhazardous fluids into the subsurface to aid in the remediation of soil and groundwater

Drainage wells, improved sinkholes and subsurface fluid distribution systems used to drain storm water runoff into a subsurface formation

Drywells used for the injection of wastes into a subsurface formation

Experimental wells used to test new technologies or to conduct tracer dye studies

Industrial cooling water return flow wells used to inject noncontact water used to cool industrial process equipment

Large capacity septic systems designed to inject greater than 5,000 gallons per day of waste or effluent

Mine sand backfill wells used to control subsidence, dispose of mining byproducts, and/or fill sections of a mine

Saltwater intrusion barrier wells used to inject water into a freshwater aquifer to prevent the intrusion of salt water into the fresh water

Septic systems designed to inject 5,000 gallons per day or less of waste or effluent, except for single family residential septic systems

Subsidence control wells used to control land subsidence caused by groundwater withdrawal

Subsurface fluid distribution systems or subsurface area drip dispersal systems used for disposal of treated effluent from a wastewater treatment plant

Wells used to dispose of nonhazardous brine generated by a desalination operation or nonhazardous drinking waste treatment residuals

Wells used to dispose of nonhazardous industrial process wastewater

Other wells not defined above and not used for activities related to energy production

Authorization/Inventory Forms and Related Information

Most Types of Class V Injection Wells

Most Class V wells, including wells used for aquifer recharge, require authorization from the Texas Commission on Environmental Quality (TCEQ) prior to construction, conversion, modification, and operation of the wells. Authorization approval for most types of Class V wells may be obtained by completing and submitting the Class V Injection Well Authorization/Inventory Form for review and approval by the executive director. 

Guidance Documents Related to Aquifer Recharge (AR)

TCEQ offers guidance for site selection criteria for aquifer recharge from stormwater (AS-487)

There are a few exceptions when authorization is obtained by completing and submitting alternate forms. The following types of Class V wells require submittal of the indicated alternate forms.

Aquifer Storage and Recovery (ASR)

ASR projects involve the injection of water into a geologic formation for subsequent recovery and beneficial use by the operator.

Authorization Form

Authorization is required before construction, conversion, modification, and/or storage or recovery operations. An ASR project may be authorized by rule, by an individual permit, or by a general permit. The TCEQ anticipates most ASR projects may be authorized by rule.

Texas Aquifer Storage & Recovery Applet (TxASR app) ! Temporarily Unavailable Due to Maintenance

The TxASR app  provides a user-friendly interface with features to assess the feasibility of water recharge, storage, and recovery. The ASR app provides an initial assessment. Complex aquifer systems may require additional numerical modeling to justify recoverability. This app is not intended as a substitute for modeling requirements in an ASR project application.

Guidance Documents Related to ASR and Arsenic

TCEQ offers guidance for minimizing potential arsenic mobilization (AS-218) and guidelines for the treatment and management of injected water to minimize the potential release of arsenic (AS-219).

Wastewater Discharge

Large capacity septic systems, septic systems which accept industrial waste, subsurface area drip dispersal systems, and subsurface fluid distribution systems are used for the disposal of treated effluent from a wastewater treatment plant.

Inventory Requirements

The TCEQ UIC Permits Section requires the submittal of a worksheet from applicants applying for a municipal or industrial wastewater discharge permit. Access to TCEQ municipal and industrial wastewater discharge webpages is provided below:

Open Loop AC Return Flow Wells

The TCEQ UIC Permits Section requires water well drillers to submit to the TCEQ a copy of the Texas Department of Licensing and Regulation Well Report Form  within 30 days from the date the well construction is completed for open loop injection and air conditioning return flow wells.

Nonhazardous Brine/Drinking Water Treatment Residuals Disposal (DWTR)

Class V injection wells are used to dispose of nonhazardous brine generated by a desalination operation or for the disposal of DWTR using a Class II injection well permitted by the Railroad Commission of Texas (RRC). DWTR containing naturally occurring radioactive material must be disposed of in a Class I well under a UIC permit and a radioactive material license in accordance with 30 TAC 336 Subchapter K.

Authorization Form

Authorization is required to authorize a Class II injection well owner or operator permitted by the RRC to dispose of nonhazardous brine generated by a desalination operation or nonhazardous DWTR into a Class II-Class V injection well.

Additional Requirements for Class V Authorizations

RRC Reports:

A Class II injection well owner or operator is required to have:

  • An active Form P-5 Organization Report in good standing with the RRC
  • A Class II RRC permit in active status

TCEQ Reports:

A Class II injection well owner or operator is required to submit semi-annual status reports and summary reports using the TCEQ-RRC Class V Reporting Worksheet (Form TCEQ-20736a).

Prohibited Disposal Wells and Large Capacity Cesspools

The TCEQ does not authorize cesspools or motor vehicle waste disposal wells. Any existing large capacity cesspools or motor vehicles waste disposal wells must be inventoried by submitting the Class V Injection Well Authorization/Inventory Form (Form TCEQ-10338). Once inventoried, the large capacity cesspools or motor vehicle waste disposal wells must be plugged.

Large Capacity Cesspools are drywells that receive untreated sanitary waste containing human excreta, and which sometimes have open bottoms and/or sometimes have perforated sides and are designed for a flow of greater than 5,000 gallons per day.

Motor vehicle waste disposal wells used for the disposal of fluids from vehicular repair or maintenance activities, such as an automotive repair shop, auto body shop, car dealership, boat, motorcycle, or airplane dealership, or repair facility.

Rules and Definitions

Rules: Title 30, Texas Administrative Code, Chapter 331 Underground Injection Control