| (56) Individual permit--A permit, as defined in the
Texas Water Code (TWC), §27.011 and §27.021, issued by the
commission or the executive director to a specific person or persons
in accordance with the procedures prescribed in the TWC, Chapter 27
(other than TWC, §27.025).
(57) Injection interval--That part of the injection
zone in which the well is authorized to be screened, perforated, or
in which the waste is otherwise authorized to be directly emplaced.
(58) Injection operations--The subsurface emplacement
of fluids occurring in connection with an injection well or wells,
other than that occurring solely for construction or initial testing.
(59) Injection well--A well into which fluids are being
injected. Components of an injection well annulus monitoring system
are considered to be a part of the injection well.
(60) Injection zone--A formation, a group of formations,
or part of a formation that receives fluid through a well.
(61) In service--The operational status when an authorized
injection well is capable of injecting fluids, including times when
the well is shut-in and on standby status.
(62) Intermediate casing--A string of casing with diameter
intermediate between that of the surface casing and that of the smaller
long-string or production casing, and which is set and cemented in
a well after installation of the surface casing and prior to installation
of the long-string or production casing.
(63) Large capacity cesspool--A cesspool that is designed
for a flow of greater than 5,000 gallons per day.
(64) Large capacity septic system--A septic system
that is designed for a flow of greater than 5,000 gallons per day.
(65) Licensed professional geoscientist--A geoscientist
who maintains a current license through the Texas Board of Professional
Geoscientists in accordance with its requirements for professional
(66) Liner--An additional casing string typically set
and cemented inside the long string casing and occasionally used to
extend from base of the long string casing to or through the injection
(67) Long string casing or production casing--A string
of casing that is set inside the surface casing and that usually extends
to or through the injection zone.
(68) Lost circulation zone--A term applicable to rotary
drilling of wells to indicate a subsurface zone which is penetrated
by a wellbore, and which is characterized by rock of high porosity
and permeability, into which drilling fluids flow from the wellbore
to the degree that the circulation of drilling fluids from the bit
back to ground surface is disrupted or "lost."
(69) Mine area--The area defined by a line through
the ring of designated monitor wells installed to monitor the production
(70) Mine plan--A plan for operations at a mine, consisting
(A) a map of the permit area identifying the location
and extent of existing and proposed production areas; and
(B) an estimated schedule indicating the sequence and
timetable for mining and any required aquifer restoration.
(71) Monitor well--Any well used for the sampling or
measurement with field instrumentation of any chemical or physical
property of subsurface strata or their contained fluids. The term
"monitor well" shall have the same meaning as the term "monitoring
well" as defined in Texas Water Code, §27.002.
(A) Designated monitor wells are those listed in the
production area authorization for which routine water quality sampling
or measurement with field instrumentation is required.
(B) Secondary monitor wells are those wells in addition
to designated monitor wells, used to delineate the horizontal and
vertical extent of mining solutions.
(C) Pond monitor wells are wells used in the subsurface
surveillance system near ponds or other pre-injection units.
(72) Motor vehicle waste disposal well--A well used
for the disposal of fluids from vehicular repair or maintenance activities
including, but not limited to, repair and maintenance facilities for
cars, trucks, motorcycles, boats, railroad locomotives, and airplanes.
(73) Native groundwater--Groundwater naturally occurring
in a geologic formation.
(74) New injection well--Any well, or group of wells,
not an existing injection well.
(75) New waste stream--A waste stream not permitted.
(76) Non-commercial facility--A Class I permitted facility
which operates only non-commercial wells.
(77) Non-commercial underground injection control (UIC)
Class I well facility--A UIC Class I permitted facility where only
non-commercial wells are operated.
(78) Non-commercial well--An underground injection
control Class I injection well which disposes of wastes that are generated
on-site, at a captured facility or from other facilities owned or
effectively controlled by the same person.
(79) Notice of change (NOC)--A written submittal to
the executive director from a permittee authorized under a general
permit providing changes to information previously provided to the
agency, or any changes with respect to the nature or operations of
the facility, or the characteristics of the waste to be injected.
(80) Notice of intent (NOI)--A written submittal to
the executive director requesting coverage under the terms of a general
(81) Off-site--Property which cannot be characterized
(82) On-site--The same or geographically contiguous
property which may be divided by public or private rights-of-way,
provided the entrance and exit between the properties is at a cross-roads
intersection, and access is by crossing, as opposed to going along,
the right-of-way. Noncontiguous properties owned by the same person
but connected by a right-of-way which the owner controls and to which
the public does not have access, is also considered on-site property.
(83) Out of service--The operational status when a
well is not authorized to inject fluids, or the well itself is incapable
of injecting fluids for mechanical reasons, maintenance operations,
or well workovers or when injection is prohibited due to the well's
inability to comply with the in-service operating standards of this
(84) Permit area--The area owned or under lease by
the permittee which may include buffer areas, mine areas, and production
(85) Plugging--The act or process of stopping the flow
of water, oil, or gas into or out of a formation through a borehole
or well penetrating that formation.
(86) Point of injection--For a Class V well, the last
accessible sampling point prior to fluids being released into the
(87) Pollution--The contamination of water or the alteration
of the physical, chemical, or biological quality of water:
(A) that makes it harmful, detrimental, or injurious:
(i) to humans, animal life, vegetation, or property;
(ii) to public health, safety, or welfare; or
(B) that impairs the usefulness or the public enjoyment
of the water for any lawful and reasonable purpose.
(88) Pre-injection units--The on-site above-ground
appurtenances, structures, equipment, and other fixtures including
the injection pumps, filters, tanks, surface impoundments, and piping
for wastewater transmission between any such facilities and the well
that are or will be used for storage or processing of waste to be
injected, or in conjunction with an injection operation.
(89) Production area--The area defined by a line generally
through the outer perimeter of injection and recovery wells used for
(90) Production area authorization--An authorization,
issued under the terms of a Class III injection well area permit,
approving the initiation of mining activities in a specified production
area within a permit area, and setting specific conditions for production
and restoration in each production area within an area permit.
(91) Production well--A well used to recover uranium
through in situ solution recovery, including an injection well used
to recover uranium. The term does not include a well used to inject
(92) Production zone--The stratigraphic interval extending
vertically from the shallowest to the deepest stratum into which mining
solutions are authorized to be introduced.
(93) Project operator--A person holding an authorization
by rule, individual permit, or general permit to undertake an aquifer
storage and recovery project or an aquifer recharge project.
(94) Public water system--A system for the provision
to the public of water for human consumption through pipes or other
constructed conveyances as defined in §290.38 of this title (relating
(95) Radioactive waste--Any waste which contains radioactive
material in concentrations which exceed those listed in 10 Code of
Federal Regulations Part 20, Appendix B, Table II, Column 2, and as
(96) Recharge injection well--A Class V injection well
used for the injection of water into a geologic formation for an aquifer
recharge project, including an improved sinkhole or cave connected
to an aquifer.
(97) Registered Well--A well registered in accordance
with the requirements of §331.221 of this title (relating to
Registration of Wells).
(98) Restoration demonstration--A test or tests conducted
by a permittee to simulate production and restoration conditions and
verify or modify the fluid handling values submitted in the permit
(99) Restored aquifer--An aquifer whose local groundwater
quality, within a production area, has, by natural or artificial processes,
returned to the restoration table values established in accordance
with the requirements of §331.107 of this title (relating to
(100) Salt cavern--A hollowed-out void space that has
been purposefully constructed within a salt formation, typically by
means of solution mining by circulation of water from a well or wells
connected to the surface.
(101) Salt cavern disposal well--For the purposes of
this chapter, regulations of the commission, and not to underground
injection control (UIC) Class II or UIC Class III wells in salt caverns
regulated by the Railroad Commission of Texas, a salt cavern disposal
well is a type of UIC Class I injection well used:
(A) to solution mine a waste storage or disposal cavern
in naturally occurring salt; and/or
(B) to inject nonhazardous, industrial, or municipal
waste into a salt cavern for the purpose of storage or disposal of
(102) Salt dome--A geologic structure that includes
the caprock, salt stock, and deformed strata surrounding the salt
(103) Salt dome cavern confining zone--A zone between
the salt dome cavern injection zone and all underground sources of
drinking water and freshwater aquifers, that acts as a barrier to
movement of waste out of a salt dome cavern injection zone, and consists
of the entirety of the salt stock excluding any portion of the salt
stock designated as an underground injection control (UIC) Class I
salt dome cavern injection zone or any portion of the salt stock occupied
by a UIC Class II or Class III salt dome cavern or its disturbed salt
(104) Salt dome cavern injection interval--That part
of a salt dome cavern injection zone consisting of the void space
of the salt dome cavern into which waste is stored or disposed of,
or which is capable of receiving waste for storage or disposal.
(105) Salt dome cavern injection zone--The void space
of a salt dome cavern that receives waste through a well, plus that
portion of the salt stock enveloping the salt dome cavern, and extending
from the boundaries of the cavern void outward a sufficient thickness
to contain the disturbed salt zone, and an additional thickness of
undisturbed salt sufficient to ensure that adequate separation exists
between the outer limits of the injection zone and any other activities
in the domal area.
(106) Salt stock--A geologic formation consisting of
a relatively homogeneous mixture of evaporite minerals dominated by
halite (NaCl) that has migrated from originally tabular beds into
a vertical orientation.
(107) Sanitary waste--Liquid or solid waste originating
solely from humans and human activities, such as wastes collected
from toilets, showers, wash basins, sinks used for cleaning domestic
areas, sinks used for food preparation, clothes washing operations,
and sinks or washing machines where food and beverage serving dishes,
glasses, and utensils are cleaned.
(108) Septic system--A well that is used to emplace
sanitary waste below the surface, and is typically composed of a septic
tank and subsurface fluid distribution system or disposal system.
(109) Stratum--A sedimentary bed or layer, regardless
of thickness, that consists of generally the same kind of rock or
(110) Subsurface fluid distribution system--An assemblage
of perforated pipes, drain tiles, or other similar mechanisms intended
to distribute fluids below the surface of the ground. This definition
includes subsurface area drip dispersal systems as defined in §222.5
of this title (relating to Definitions).