16 Tex. Admin. Code § 4.110 - [Effective 7/1/2025] Definitions

The following words and terms when used in this chapter shall have the following meanings unless the context clearly indicates otherwise.

(1) 25-year, 24-hour rainfall event--The maximum 24-hour precipitation event, in inches, with a probable recurrence interval of once in 25 years, as defined by the National Weather Service and published by the National Oceanic and Atmospheric Administration for the county in which the waste management activity is occurring.

(2) 100-year flood--A flood that has a 1.0% or greater chance of occurring in any given year.

(3) 100-year flood plain--The lowland and relatively flat areas adjoining inland and coastal waters, including flood-prone areas of offshore islands, that are inundated by the 100-year flood, as determined from maps or other data from the U.S. Army Corps of Engineers or the Federal Emergency Management Agency (FEMA).

(4) Action leakage rate--The calculated volume of waste liquid that has bypassed the primary liner into the leak detection layer at a rate of gallons per acre per day that if exceeded indicates failure of the primary liner.

(5) Active cell--A waste management unit that has received oil and gas waste and has not completed closure.

(6) Active life--The period of time beginning when a waste management unit first receives waste and ending when closure of the waste management unit is complete.

(7) Activities associated with the exploration, development, and production of oil or gas or geothermal resources--Activities associated with:

(A) the drilling of exploratory wells, oil wells, gas wells, injection wells, disposal wells, or geothermal resource wells;

(B) the production of oil or gas or geothermal resources, including activities associated with:

(i) the drilling of injection water source wells that penetrate the base of usable quality water;

(ii) the drilling of cathodic protection holes associated with the cathodic protection of wells and pipelines subject to the jurisdiction of the Commission to regulate the production of oil or gas or geothermal resources;

(iii) the drilling of seismic holes and core holes subject to the jurisdiction of the Commission to regulate the exploration, development, and production of oil or gas or geothermal resources;

(iv) gasoline plants, natural gas or natural gas liquids processing plants, pressure maintenance plants, or repressurizing plants;

(v) any underground natural gas storage facility, provided the terms "natural gas" and "storage facility" shall have the meanings set out in the Texas Natural Resources Code § 91.173;

(vi) any underground hydrocarbon storage facility, provided the terms "hydrocarbons" and "underground hydrocarbon storage facility" shall have the meanings set out in the Texas Natural Resources Code § 91.201; and

(vii) the storage, handling, reclamation, gathering, transportation, or distribution of oil or gas prior to the refining of such oil or prior to the use of such gas in any manufacturing process or as a residential or industrial fuel;

(C) the operation, abandonment, and proper plugging of wells subject to the jurisdiction of the Commission to regulate the exploration, development, and production of oil or gas or geothermal resources; and

(D) the management of oil and gas waste or any other substance or material associated with any activity listed in subparagraphs (A) - (C) of this paragraph, except for waste generated in connection with activities associated with gasoline plants, natural gas or natural gas liquids processing plants, pressure maintenance plants, or repressurizing plants if that waste is a hazardous waste as defined by the administrator of the United States Environmental Protection Agency (EPA) pursuant to the federal Solid Waste Disposal Act, as amended (42 USC § 6901, et seq.).

(8) Affected person--A person who, as a result of the activity sought to be permitted, has suffered or may suffer actual injury or economic damage other than as a member of the general public or a competitor.

(9) Aquifer--A geological formation, group of formations, or portion of a formation capable of yielding significant quantities of groundwater to wells or springs.

(10) ASTM--ASTM International (successor to the American Society for Testing and Materials).

(11) Authorized--An activity that is permitted or allowed by a rule.

(12) Authorized pit--A reserve pit, mud circulation pit, completion/workover pit, makeup water pit, fresh mining water pit, water condensate pit, or produced water recycling pit that is permitted by rule and described and operated in accordance with Division 3 of this subchapter (relating to Operations Authorized by Rule).

(13) Basic sediment--A mixture of crude oil or lease condensate, water, sediment, and other substances or hydrocarbon-bearing materials that are concentrated at the bottom of tanks and pipeline storage tanks (also referred to as "basic sediment and water" or "tank bottoms").

(14) Brine pit--A pit used for storage of brine in connection with the solution mining of brine, the operation of an underground hydrocarbon storage facility, or other activities associated with oil and gas exploration, development, storage or production that involve the creation or use of a salt cavern.

(15) Buffer zone--The minimum distance allowed between a waste management unit and another feature, such as a property boundary, surface water, or water well.

(16) Carrier--A person who is permitted to transport oil and gas wastes. A carrier of another person's oil and gas wastes may be a generator of its own oil and gas wastes. A permitted waste hauler is a carrier.

(17) Coastal Management Program (CMP) rules--The enforceable rules of the Texas Coastal Management Program codified at 31 Texas Administrative Code Chapters 26 through 29.

(18) Coastal Natural Resource Area (CNRA)--One of the following areas defined in Texas Natural Resources Code § 33.203: coastal barriers, coastal historic areas, coastal preserves, coastal shore areas, coastal wetlands, critical dune areas, critical erosion areas, gulf beaches, hard substrate reefs, oyster reefs, submerged land, special hazard areas, submerged aquatic vegetation, tidal sand or mud flats, water in the open Gulf of Mexico, and water under tidal influence.

(19) Coastal waters--Waters along the coast under the jurisdiction of the State of Texas, including tidal influence and waters of the open Gulf of Mexico.

(20) Coastal zone--The area within the boundary established in 31 Texas Administrative Code § 27.1 (relating to Coastal Management Program Boundary).

(21) Commercial facility--A facility permitted under Division 4 of this subchapter (relating to Requirements for All Permitted Waste Management Operations), whose owner or operator receives compensation from others for the management of oil field fluids or oil and gas wastes and whose primary business purpose is to provide these services for compensation.

(22) Commission--The Railroad Commission of Texas.

(23) Completion/workover pit--A pit used for storage or disposal of spent completion fluids and solids, workover fluids and solids, and drilling fluids and solids, silt, debris, water, brine, oil scum, paraffin, or other materials which have been cleaned out of the wellbore of a well being completed, worked over, or plugged.

(24) Contact stormwater--Stormwater that has come into contact with any amount of oil and gas wastes or areas that contain or have contained oil and gas wastes. See also "Non-contact stormwater" and "Stormwater."

(25) Container--A means of primary containment used for the management of oil and gas waste such as a pit, sump, tank, vessel, truck, barge, or other receptacle.

(26) Critical area--A coastal wetland, an oyster reef, a hard substrate reef, submerged aquatic vegetation, or a tidal sand or mud flat as defined in Texas Natural Resources Code § 33.203.

(27) Dewater--To remove free liquids from a media such that the remaining material passes a Paint Filter Liquids Test (EPA Method 9095B, as described in "Test Methods for Evaluating Solid Wastes, Physical/Chemical Methods," EPA Publication Number SW-846). See also "Free liquids".

(28) Director--The Director of the Oil and Gas Division or the Director's delegate.

(29) Discharge--To allow a liquid, gas, or other substance to flow out from where it has been confined.

(30) Disposal--The act of conducting, draining, discharging, emitting, throwing, releasing, depositing, burying, dumping, placing, abandoning, landfarming, allowing seepage, or causing or allowing any such act of disposal of any oil field fluid, oil and gas waste, or other substance or material subject to regulation by the Commission.

(31) Disposal pit--A pit used for the permanent storage of oil and gas waste.

(32) District Director--The Director of the Commission district where the management, disposal, or recycling of oil and gas wastes is located or the District Director's delegate.

(33) District Office--The Commission District Office in the Commission district where the waste management, disposal, and/or recycling is located.

(34) Drill cuttings--Bits of rock or soil cut from a subsurface formation by a drill bit during the process of drilling an oil or gas well or other wells within the Commission's jurisdiction and lifted to the surface by means of the circulation of drilling mud. The term includes any associated sand, silt, drilling fluid, spent completion fluid, workover fluid, debris, water, brine, oil scum, paraffin, or other material cleaned out of the wellbore.

(35) Drilling fluid--Any of a number of liquid and gaseous fluids and mixtures of fluids and solids (as solid suspensions, mixtures and emulsions of liquids, gases and solids) used in operations to drill boreholes into the earth.

(36) Electrical conductivity--A numerical expression of the ability of a material to carry a current, normally expressed in millimhos/centimeter (the reciprocal of resistivity). It is frequently used to estimate salinity in terms of total dissolved solids. In soil analysis, electrical conductivity may be used as one measure to evaluate a soil's ability to sustain plant growth.

(37) Environmental Protection Agency (EPA)--The United States Environmental Protection Agency.

(38) Facility--A site that shares a common area, common access, and a common purpose where oil field fluids or oil and gas wastes are managed. It may include one or more waste management units, may include permitted or authorized activities, and may be designated as either commercial or non-commercial.

(39) Free liquids--Liquids which readily separate from the solid portion of a waste under ambient temperature and pressure.

(40) Freeboard--The vertical distance between the top of a pit or berm and the highest point of the contents of the pit or berm.

(41) Fresh mining water pit--A pit used in conjunction with a brine mining injection well for storage of fresh water used for solution mining of brine.

(42) Generator--A person that generates oil and gas wastes.

(43) Geomembrane--An impermeable polymeric sheet material that is impervious to liquid and gas if it maintains its integrity and is used as an integral part of an engineered structure designed to limit the movement of liquid or gas in a system.

(44) Geotextile--A sheet material that is less impervious to liquid than a geomembrane but more resistant to penetration damage, and is used as part of an engineered structure or system to serve as a filter to prevent the movement of soil fines into a drainage system, to provide planar flow for drainage, to serve as a cushion to protect geomembranes, or to provide structural support.

(45) Groundwater--Subsurface water in a zone of saturation.

(46) Hydrocarbon condensate--Hydrocarbon liquids that condense from a natural gas stream.

(47) Inert oil and gas waste--Nonreactive, nontoxic, and essentially insoluble oil and gas wastes, including, but not limited to, concrete, glass, wood, metal, wire, plastic, synthetic liners, fiberglass, soil, dirt, clay, sand, gravel, brick, and trash. The term excludes asbestos or asbestos-containing waste, and oil and gas naturally occurring radioactive material (NORM) waste.

(48) Karst terrain--An area where karst topography, with its characteristic surface and/or subterranean features, is developed principally as the result of dissolution of limestone, dolomite, or other soluble rock. Characteristic physiographic features present in karst terrains include, but are not limited to, sinkholes, sinking streams, caves, large springs, and blind valleys.

(49) Land application--A method for the permanent disposition of low-chloride aqueous oil and gas waste by which the liquid waste is applied directly to the ground surface in a controlled manner via sprinkler or other irrigation systems without tilling or mixing with the native soils and without runoff to surface water or infiltration to groundwater.

(50) Landfarming--An authorized or permitted waste management practice in which low chloride, water-based drilling fluids, or oil and gas wastes are mixed with, or tilled into, the native soils in such a manner that the waste will not migrate from the authorized or permitted landfarming cell.

(51) Landfarming cell--The bermed area into which oil and gas waste is applied to the land and includes landfarming and landtreatment cells.

(52) Landtreating--An authorized or permitted waste management practice in which oil-based drilling fluids, oil impacted soils, and oil and gas wastes are mixed with or tilled into the native soil to degrade oil, grease, or other organic wastes through biological processes and in such a manner that the waste will not migrate from the authorized or permitted landtreatment cell.

(53) Leak detection system--A system used to detect leaks below the liner of pits.

(54) Liner--A continuous layer of impervious materials, synthetic or natural, beneath and on the sides of a pit that restricts or prevents the downward or lateral release or migration of oilfield fluids or oil and gas wastes.

(55) Makeup water pit--A pit used in conjunction with a drilling rig, completion operations, or a workover for storage of water used to make up drilling fluid or completion fluid.

(56) Manage or management of oil and gas waste--The receiving, handling, storage, treatment, processing, transportation, reclamation, recycling, and/or disposal of oil and gas wastes.

(57) Manifest--An electronic or paper document used to track shipments of oil and gas waste that is authenticated by all parties (the generator, carrier, and receiver) in the transfer of oil and gas waste, and contains information on the waste type, source, quantity, and instructions for handling.

(58) Mined brine--Brine produced from a brine mining injection well by solution of subsurface salt formations. The term does not include saltwater produced incidentally to the exploration, development, and production of oil or gas or geothermal resources.

(59) Mud circulation pit--A pit used in conjunction with drilling rig for storage of drilling fluid currently being used in drilling operations.

(60) Natural gas or natural gas liquids processing plant--A plant whose primary function is the extraction of natural gas liquids from field gas, the fractionation of natural gas liquids, and the production of pipeline-quality gas for transportation by a natural gas transmission pipeline. The term does not include a separately located natural gas treating plant for which the primary function is the removal of carbon dioxide, hydrogen sulfide, or other impurities from the natural gas stream. A separator, dehydration unit, heater treater, sweetening unit, compressor, or similar equipment shall be considered a component of a natural gas or natural gas liquids processing plant only if it is located at a plant the primary function of which is the extraction of natural gas liquids from field gas or fractionation of natural gas liquids.

(61) Naturally occurring radioactive material (NORM)--Naturally occurring materials not regulated under the Atomic Energy Act whose radionuclide concentrations have been increased by or as a result of human practices. NORM does not include the natural radioactivity of rocks or soils, or background radiation, but instead refers to materials whose radioactivity is concentrated by controllable practices (or by past human practices). NORM does not include source, byproduct, or special nuclear material.

(62) Non-commercial facility--A facility authorized or permitted under this chapter that is not a commercial facility as defined in paragraph (21) of this section.

(63) Non-contact stormwater--Stormwater that, by design or direction, has not come into contact with any oil or gas wastes and is not otherwise designated as contact stormwater pursuant to §4.110(24). See also "Contact stormwater" and "Stormwater."

(64) Oil and gas NORM waste--Any solid, liquid, or gaseous material or combination of materials (excluding source material, special nuclear material, and by-product material) that in its natural physical state spontaneously emits radiation, is discarded or unwanted, constitutes, is contained in, or has contaminated oil and gas waste, and prior to treatment or processing that reduces the radioactivity concentration, exceeds exemption criteria specified in 25 Texas Administrative Code § 289.259(d) (relating to Licensing of Naturally Occurring Radioactive Material (NORM)).

(65) Oil and gas wastes--As defined in Texas Natural Resources Code § 91.1011, the term:

(A) means waste that arises out of or incidental to the drilling for or producing of oil or gas, including waste arising out of or incidental to:

(i) activities associated with the drilling of injection water source wells which penetrate the base of useable quality water;

(ii) activities associated with the drilling of cathodic protection holes associated with the cathodic protection of wells and pipelines subject to the jurisdiction of the Commission;

(iii) activities associated with gasoline plants, natural gas or natural gas liquids processing plants, pressure maintenance plants, or repressurizing plants;

(iv) activities associated with any underground natural gas storage facility, provided the terms "natural gas" and "storage facility" shall have the meanings set out in Texas Natural Resources Code § 91.173;

(v) activities associated with any underground hydrocarbon storage facility, provided the terms "hydrocarbons" and "underground hydrocarbon storage facility" shall have the meanings set out in Texas Natural Resources Code § 91.201; and

(vi) activities associated with the storage, handling, reclamation, gathering, transportation, or distribution of oil or gas prior to the refining of such oil or prior to the use of such gas in any manufacturing process or as a residential or industrial fuel;

(B) includes salt water, brine, sludge, drilling mud, and other liquid, semiliquid, or solid waste material; but

(C) does not include waste arising out of or incidental to activities associated with gasoline plants, natural gas or natural gas liquids processing plants, pressure maintenance plants, or repressurizing plants if that waste is a hazardous waste as defined by the administrator of the United States Environmental Protection Agency pursuant to the federal Solid Waste Disposal Act, as amended by the Resource Conservation and Recovery Act, 42 U.S.C. 6901 et seq., as amended.

(66) Oil field fluids--Fluid used or reused in connection with activities associated with the exploration, development, and production of oil or gas or geothermal resources, fluids to be used or reused in connection with activities associated with the solution mining of brine, and mined brine. The term "oil field fluids" includes, but is not limited to, drilling fluids, completion fluids, surfactants, and other chemicals used in association with oil and gas activities, but does not include produced oil, condensate, gas, or water that is not oil and gas waste. Oil field fluids no longer used or reused in connection with activities associated with the exploration, development, and production of oil or gas or geothermal resources, and oil field fluids that have been abandoned, are considered an oil and gas waste.

(67) Operator--A person, acting for itself or as an agent for others, designated to the Railroad Commission of Texas as the person with responsibility for complying with the Commission's rules and regulations in any acts subject to the Commission's jurisdiction.

(68) Partially treated waste--Oil and gas waste that has been treated or processed with the intent of being recycled, but which has not been determined to meet the environmental and engineering standards for a recyclable product established by the Commission in this subchapter or in a permit issued pursuant to this subchapter.

(69) Person--A natural person, corporation, organization, government or governmental subdivision or agency, business trust, estate, trust, partnership, association, or any other legal entity.

(70) Pit--A container for which earthen materials provide structure, shape, and foundation support. A container that includes a concrete floor or sidewall is a pit. A tank, as defined in paragraph (89) of this section, is not a pit.

(71) Pollution--The alteration of the physical, thermal, chemical, or biological quality of, or the contamination of, any surface or subsurface water that renders the water harmful, detrimental, or injurious to humans, animal life, vegetation, or property, or to public health, safety, or welfare, or impairs the usefulness or the public enjoyment of the water for any lawful or reasonable purpose.

(72) Primary containment--Measures put into place to confine, control, and secure a material to a defined space. See also "Container."

(73) Produced water--The water that was present in a subsurface formation and was brought to the surface during oil and gas exploration and production activities.

(74) Produced water recycling--The recycling of produced water and other aqueous fluid wastes produced from a wellbore during oil and gas exploration and production activities.

(75) Produced water recycling pit--An authorized pit used to manage produced water and other aqueous fluid wastes produced from a wellbore during oil and gas exploration and production activities.

(76) Public area--A dwelling, place of business, church, school, hospital, school bus stop, government building, any portion of a park, city, town, village, or other similar area that can expect to be populated.

(77) Public water system--A source of potable water for the public's use that has at least 15 service connections or serves at least 25 individuals for at least 60 days out of the year. This includes people that live in houses served by a system, but can also include employees, customers, or students.

(78) Pressure maintenance plant or repressurizing plant--A plant for processing natural gas for reinjection for reservoir pressure maintenance or repressurizing in a natural gas recycling project. These terms do not include a compressor station along a natural gas pipeline system or a pump station along a crude oil pipeline system.

(79) Receiver--A person who manages oil and gas waste that is received from a generator, another receiver, or carrier. A receiver of another operator's oil and gas wastes may be a generator of its own oil and gas wastes.

(80) Recyclable product--A reusable material that has been created from the treatment and/or processing of oil and gas waste as authorized or permitted by the Commission and that meets the environmental and engineering standards established by the permit or authorization for the intended use, and is used as a legitimate commercial product. A recyclable product is not a waste but may become a waste if it is abandoned or disposed of rather than recycled as authorized by the permit or authorization.

(81) Recycle--To process and/or use or re-use oil and gas wastes as a product for which there is a legitimate commercial use. This term also includes the actual use or re-use of oil and gas wastes. For the purpose of this chapter, the term "recycle" does not include injection pursuant to a permit issued under § 3.46 of this title (relating to Fluid Injection into Productive Reservoirs).

(82) Reserve pit--A pit used in conjunction with drilling rig for collecting spent drilling fluids; cuttings, sands, and silts; and wash water used for cleaning drill pipe and other equipment at the well site. Reserve pits are sometimes referred to as slush pits or mud pits.

(83) Secondary containment--Measures put into place to contain spills and prevent them from contaminating the surrounding area, such as dikes, berms, or other barriers. See also "Container" and "Primary containment."

(84) Sensitive area--An area defined by the presence of factors, whether one or more, that make it vulnerable to pollution from oil and gas surface waste management activities. Factors that are characteristic of sensitive areas include the presence of shallow groundwater or pathways for communication with deeper groundwater; proximity to surface water, including lakes, rivers, streams, dry or flowing creeks, irrigation canals, water wells, stock tanks, and wetlands; proximity to natural wildlife refuges or parks; or proximity to commercial or residential areas.

(85) Solid oil and gas waste--Oil and gas waste that is determined not to contain "free liquids" as defined by EPA Method 9095B (Paint Filter Liquids Test), as described in "Test Methods for Evaluating Solid Wastes, Physical/Chemical Methods" (EPA Publication Number SW-846).

(86) Storage or storing--The keeping, holding, accumulating, or aggregating of oil and gas waste for a temporary or indeterminate period.

(87) Stormwater--Water that falls onto and flows over the ground surface and does not infiltrate into the soil. See also "Contact stormwater" and "Non-contact stormwater."

(88) Surface and subsurface water--Groundwater, percolating, perched or otherwise, and lakes, bays, ponds, impounding reservoirs, springs, rivers, streams, creeks, estuaries, marshes, wetlands, inlets, canals, the Gulf of Mexico inside the territorial limits of the state, and all other bodies of surface water, natural or artificial, inland or coastal, fresh, saline, or salt, navigable or non-navigable, and including the beds and banks of all watercourses and bodies of surface water, that are wholly or partially inside or bordering the state or inside the jurisdiction of the state.

(89) Tank--A rigid, non-concrete, non-earthen container that provides its own structure and shape.

(90) TCEQ--The Texas Commission on Environmental Quality or its successor agencies.

(91) Technical Permitting Section or Technical Permitting--The Technical Permitting Section within the Oil and Gas Division of the Railroad Commission of Texas, located in Austin, Texas.

(92) Treated fluid--Fluid oil and gas waste that has been treated to remove impurities such that the fluid can be reused or recycled. Treated fluid that is abandoned or disposed of is classified as an oil and gas waste. Once treated fluid is reused or recycled, it is not classified as an oil and gas waste.

(93) Unified Soil Classification System--The standardized system devised by the United States Army Corps of Engineers for classifying soil types.

(94) Waste management unit--A container, structure, pad, cell, or area in or on which oil and gas wastes are managed.

(95) Water condensate pit--A pit used for storage or disposal of water condensed from natural gas.

(96) Wetland--An area including a swamp, marsh, bog, prairie pothole, or similar area having a predominance of hydric soils that are inundated or saturated by surface or groundwater at a frequency and duration sufficient to support and that under normal circumstances supports the growth and regeneration of hydrophytic vegetation. The term "hydric soil" means soil that, in its undrained condition, is saturated, flooded, or ponded long enough during a growing season to develop an anaerobic condition that supports the growth and regeneration of hydrophytic vegetation. The term "hydrophytic vegetation" means a plant growing in water or a substrate that is at least periodically deficient in oxygen during a growing season as a result of excessive water content. The term "wetland" does not include irrigated acreage used as farmland; a man-made wetland of less than one acre; or a man-made wetland for which construction or creation commenced on or after August 28, 1989, and which was not constructed with wetland creation as a stated objective, including but not limited to an impoundment made for the purpose of soil and water conservation which has been approved or requested by soil and water conservation districts (Texas Water Code § 11.502.).

Notes

16 Tex. Admin. Code § 4.110

Adopted by Texas Register, Volume 50, Number 01, January 3, 2025, TexReg 0065, eff. 7/1/2025