California Code of Regulations › Title 23 - Waters › Division 3 - State Water Resources Control Board and Regional Water Quality Control Boards › Chapter 15 - Discharges of Hazardous Waste to Land › Article 10 - Definitions › Section 2601 - Technical Definitions

Current through Register 2024 Notice Reg. No. 28, July 12, 2024
"Active life" means the period during which wastes are
					 being discharged to a waste management unit. The active life continues until
					 final closure of the waste management unit has been initiated pursuant to
					 Article 8 of this chapter. For surface impoundments, the active life includes
					 any time when the impoundment contains liquid fluid, including waste and
					 leachate.
"Affected medium" means any medium (e.g., ground water,
					 surface water, or the unsaturated zone) that has been affected by a release
					 from a waste management unit.
"Aquifer" means a geologic formation, group of formations,
					 or part of a formation capable of yielding a significant amount of ground water
					 to wells or springs.
"Attitude" means the orientation in space of a geologic
					 structural feature or structural element position of a geologic bed, stratum,
					 fracture, or surface relative to the horizontal.
"Background" means the concentrations or measures of
					 constituents or indicator parameters in water or soil that has not been
					 affected by waste constituents, or leachate from a the waste management unit
					 being monitored.
"Background monitoring point" means a well, device, or
					 location specified in the waste discharge requirements at which monitoring for
					 background water quality or background soil quality is conducted.
"Background plot" means an area adjacent to a waste
					 management unit used for land treatment that can reasonably be expected to have
					 the same, or similar soil conditions as were present at the waste management
					 unit prior to discharges of waste.
"Best management practices" means a practice, or
					 combination of practices, that is the most effective and feasible means of
					 controlling pollution generated by nonpoint sources for the attainment of water
					 quality objectives.
"Capillary forces" means the adhesive force between liquids
					 and solids which, in the case of ground water hydrology, causes soil-pore
					 liquid to move in response to differences in matric potential. This effect
					 causes water to rise from a saturated zone into the unsaturated zone, thereby
					 creating a capillary fringe forces that cause ground water to rise above the
					 surface of the saturated zone into the spaces between soil particles in the
					 unsaturated zone.
"Classified waste management unit" means a waste management
					 unit that has been classified by a regional board according to the provisions
					 of Article 3 of this chapter.
"Closure" means termination of waste discharges at a waste
					 management unit and operations necessary to prepare the closed unit for
					 post-closure maintenance. Closure may be undertaken incrementally.
"Coefficient of variation" means the standard deviation
					 divided by the mean. It is a statistical measure of the dispersion of
					 individual samples relative to the mean value of the samples.
"Concentration limit" means the value for a constituent
					 specified in the water quality protection standard including, but not limited
					 to, values for concentration, temperature, pH, conductivity, and
					 resistivity.
"Confined animal facility" means any place where cattle,
					 calves, sheep, swine, horses, mules, goats, fowl, or other domestic animals are
					 corralled, penned, tethered, or otherwise enclosed or held and where feeding is
					 by means other than grazing.
"Constituent" means an element or compound which occurs in
					 or is likely to be derived from waste discharged to the waste management unit
					 or a component of waste which is detectable.
"Constituents of concern" means any waste constituents,
					 reaction products, and hazardous constituents that are reasonably expected to
					 be in or derived from waste contained in a waste management unit.
"Containment" means the use of waste management unit
					 characteristics or installed systems and structures to prevent or restrict the
					 release of waste constituents or leachate.
"Containment feature" means any feature, whether natural or
					 artificial, used to contain waste constituents or leachate.
"Containment structure" means an artificial feature
					 installed to contain waste constituents or leachate.
"Contaminated materials" means materials that contain waste
					 constituents, or leachate.
"Control chart" means a graphical method for evaluating
					 whether a process is or is not in a state of statistical control.
"Cover" means a membrane or earthen layer placed over the
					 closed portion of a waste management unit.
"Cross-contamination" means a condition created when a
					 drill hole, boring, or improperly-constructed well forms a pathway for fluid
					 movement between a saturated zone which contains pollutants and a formerly
					 separated saturated zone containing uncontaminated ground water.
"Cutoff wall" means a subsurface barrier to lateral fluid
					 movement which extends from in-place natural geologic materials with the
					 required permeability to ground surface.
"Decomposable waste" means waste which, under suitable
					 natural conditions, can be transformed through biological and chemical
					 processes into compounds which do not impair the quality of waters of the
					 state. Incomplete decomposition, may result in some water quality degradation
					 (e.g., hardness, taste, odor, etc.).
"Dedicated" means a waste management unit which is used
					 exclusively for discharges of particular wastes.
"Dendritic" means a subdrain system that is arranged in a
					 branching pattern.
"Dewatered sludge" means residual semi-solid waste from
					 which free liquid has been evaporated, or otherwise removed.
"Discharger" means any person who discharges waste which
					 could affect the quality of waters of the state, and includes any person who
					 owns a waste management unit or who is responsible for the operation of a waste
					 management unit. When referring to dischargers of hazardous waste, the terms
					 "discharge" and "waste" in this definition have the same meaning as they would
					 have under the definitions for these terms provided in section
					 66260.10 of Chapter 11 of Division
					 4.5 of Title 22, CCR, effective July 1, 1991.
"DTSC" means Department of Toxic Substances Control.
"Electrical conductivity" means the relative ability of
					 water to conduct electrical current. It depends on the ion concentration of and
					 can be used to approximate the total filterable residue (total dissolved
					 solids) in the water.
"Excess exposure" means that, for an organism exposed to a
					 release from a waste management unit, the combined effect of all hazardous
					 constituents in the organism's environment is such that the organism will
					 suffer some measureable adverse effect on health or reproductive success, which
					 is partly or wholely attributable to the release.
"External hydrogeologic forces" means seasonal and other
					 fluctuations in ground water levels, and any other hydraulic condition which
					 could cause a change in the hydraulic stress on a containment structure.
"Facility" - See "Waste Management Facility."
"Facility wastewater" means all wastewater, from whatever
					 source, produced at a confined animal facility.
"Floodplain" means the land area which is subject to
					 flooding in any year from any source.
"Freeboard" means the vertical distance between the lowest
					 point along the top of a surface impoundment dike, berm, levee, or other
					 similar feature and the surface of the liquid contained therein.
"Free liquid" means liquid which readily separates from the
					 solid portions of waste under ambient temperature and pressure. Free liquids
					 are not present when a 100 milliliter representative sample of the waste can be
					 completely retained in a standard 400 micron conical paint filter for 5 minutes
					 without loss of any portion of the waste from the bottom of the filter (or an
					 equivalent test approved by DTSC).
"Geologic materials" means in-place naturally occurring
					 surface and subsurface rock and soil.
"Ground acceleration" means acceleration of earth particles
					 caused by an earthquake.
"Ground rupture" means disruption of the ground surface due
					 to an earthquake any structural disruption of the ground surface due to natural
					 or man-made forces; e.g., faulting, landslides, subsidence.
"Ground water" means (for the purpose of this chapter)
					 water below the land surface that is at or above atmospheric pressure.
"Grout curtain" means a subsurface barrier to fluid
					 movement, installed by injecting grout mixtures (such as cement, silicates,
					 synthetic resins, etc.) to fill and seal fractures in rock.
"Hazardous constituent" means a constituent identified in
					 Appendix VIII to Chapter 11 of Division 4.5 of Title 22, CCR, or an element,
					 chemical compound, or mixture of compounds which is a component of a waste or
					 leachate and which has a physical or chemical property that causes the waste or
					 leachate to be identified as a hazardous waste by the California Department of
					 Toxic Substances Control.
"Hazardous waste" means any waste which, under Article 1,
					 Chapter 11, Division 4.5 (§
										66261.3 et seq.) of Title 22 of
					 this code, is required to be managed according to Division 4.5 of Title 22 of
					 this code.
"Head" or "hydraulic head" means the pressure exerted by
					 fluid on a given area. It is caused by the height of the fluid surface above
					 the area.
"Holocene fault" means a fault which is or has been active
					 during the last 11,000 years.
"Inactive mining waste management unit" means any area
					 containing mining wastes which is located at a present or former mining or
					 milling site, and where all mining operations and discharges of mining waste
					 ended and have not been resumed for 5 years, or more.
"Independent sample" means an individual sample of a
					 monitored medium, obtained from a given monitoring point, that:
(1) does not contain a parcel of the medium
				  that has been previously sampled at that monitoring point sufficient to cause a
				  measurable effect in the analytical results; and
(2) has not been otherwise affected
				  differently than any other individual sample or group of samples with which it
				  will be compared.
In applying No. 1 above to ground water monitoring, the
					 parcel of water of interest is the parcel of water that was in the well bore at
					 the time of any previous sampling event.
"Indicator parameters" means measurable physical or
					 chemical characteristics of water or soil-pore moisture which are used to
					 detect the presence of waste constituents in water or soil-pore moisture, or
					 the effects of waste constituents on waters of the state.
"Interim cover" means any cover other than the final cover.
					 It includes daily cover and intermediate cover as defined in Title 14 of this
					 code.
"Landfill" means a waste management unit at which waste is
					 discharged in or on land for disposal. It does not include surface impoundment,
					 or waste pile, land treatment, or soil amendments.
"Land treatment unit" or "land treatment facility" means a
					 waste management unit at which liquid and solid waste is discharged to, or
					 incorporated into, soil for degradation, transformation, or immobilization
					 within the treatment zone. Such units are disposal units if the waste will
					 remain after closure.
"Leachate" means any liquid fluid, formed by the drainage
					 of liquids from waste or by the percolation or flow of liquid through waste. It
					 includes any constituents extracted from the waste and dissolved or suspended
					 in the fluid.
"Liner" means a continuous layer of natural or artificial
					 material or a continuous membrane of artificial material installed beneath or
					 on the sides of a waste management unit, which acts as a barrier to vertical or
					 lateral fluid movement.
"Liquid waste" means any waste materials which are not
					 spadable.
"Manure" means the accumulated moist animal excrement that
					 does not undergo decomposition or drying as would occur on open grazing land or
					 natural habitat. This definition shall include feces and urine which may be
					 mixed with bedding materials, spilled feed, or soil.
"Maximum credible earthquake" means the maximum earthquake
					 that appears capable of occurring under the presently known geologic framework.
					 In determining the maximum credible earthquake, little regard is given to its
					 probability of occurrence except that its likelihood of occurring is great
					 enough to be of concern.
"Maximum probable earthquake" means the maximum earthquake
					 that is likely to occur during a 100-year interval.
"Mining waste" means all waste materials (solid,
					 semi-solid, and liquid) from the mining and processing of ores and minerals
					 including soil, waste rock, and other forms of overburden as well as tailings,
					 slag, and other processed mining wastes.
"Moisture-holding capacity" means the amount of liquid
					 which can be held against gravity by waste materials without generating free
					 liquid.
"Monitoring parameter" means one of the set of parameters
					 specified in the waste discharge requirements for which monitoring is
					 conducted. Monitoring parameters shall include physical parameters, waste
					 constituents, reaction products, and hazardous constituents, that provide a
					 reliable indication of a release from a waste management unit.
"Monitoring point" means a well, device, or location
					 specified in the waste discharge requirements at which monitoring is conducted
					 and at which the water quality protection standard applies.
"Operating" means waste management units which are
					 currently receiving wastes. It includes temporarily idle units containing
					 wastes and at which discharges of waste may resume.
"Peak stream flow" means the maximum expected flow of
					 surface water at a waste management facility from a tributary watershed for a
					 given recurrence interval.
"Perched ground water" means a body of unconfined ground
					 water separated from the zone of saturation by a portion of the unsaturated
					 zone. Such perched water may be either permanent or ephemeral.
"Permeability" means the ability of natural and artificial
					 materials to transmit fluid.
"Physical parameter" means any measurable physical
					 characteristic of a substance including, but not limited to, temperature,
					 electrical conductivity, pH, and specific gravity.
"Point of compliance" means a vertical surface located at
					 the hydraulically downgradient limit of a waste management unit that extends
					 through the uppermost aquifer underlying the unit.
"Post-closure maintenance" means all activities undertaken
					 at a closed waste management unit to maintain the integrity of containment
					 features and to monitor compliance with applicable performance
					 standards.
"Post-closure maintenance period" means the period after
					 closure during which the waste could have an adverse effect on the quality of
					 the waters of the state.
"Probable maximum precipitation" means the estimated amount
					 of precipitation for a given duration, drainage area, and time of year, which
					 approaches and approximates the maximum that is physically possible within the
					 limits of contemporary hydrometeorological knowledge and techniques. These is
					 virtually no risk of its being exceeded.
"P-value" means the smallest significance level for which
					 the null hypothesis would be rejected, based on the data that was actually
					 observed.
"Rapid geologic change" means alteration of the ground
					 surface through such actions as landslides, subsidence, liquefaction, and
					 faulting.
"R Chart (range chart)" means a control chart for
					 evaluating the variability within a process in terms of the subgroup range
					 R.
"Reconstruction" means modification to an existing waste
					 management unit which entails costs amounting to 50 percent or more of the
					 initial cost of the unit.
"Relative compaction" means the degree of compaction
					 achieved, as a percentage of the laboratory compaction, in accordance with
					 accepted civil engineering practices.
"Runoff" means any precipitation, leachate, or other liquid
					 that drains from any part of a waste management unit.
"Runon" means any precipitation, leachate, or other liquid
					 that drains onto any part of a waste management unit.
"Saturated zone" means an underground zone in which all
					 openings in and between natural geologic materials are filled with
					 water.
"Semi-solid waste" means waste containing less than 50
					 percent solids.
"Sensitive biological receptor of concern" means a member
					 of any species of organism whose members are likely to be exposed to a release
					 from a waste management unit and experience some measurable adverse effect as a
					 result of that exposure.
"Slope failure" means downward and outward movement of
					 ground slopes (e.g., natural rock, soil, artificial fills, or continuations of
					 these materials).
"Sludge" means residual solids and semi-solids from the
					 treatment of water, wastewater, and other liquids. It does not include liquid
					 effluent discharged from such treatment processes.
"Soil-pore liquid" means the liquid contained in openings
					 between particles of soil in the unsaturated zone.
"Sorbent" means a substance which takes up and holds a
					 liquid either by absorption or adsorption.
"Statistically significant" means that the measured
					 difference between a sample value (e.g., monitoring samples) and background
					 values (or values set as water quality objectives, etc.) is greater than the
					 difference that could be measured between various samples from substances known
					 to have the same characteristics a statistical test has a p-value that is small
					 enough for the null hypothesis to be rejected.
"Storage" means the holding of waste for a temporary
					 period, at the end of which, the waste is either treated or is discharged
					 elsewhere.
"Storm" means the maximum precipitation for a given
					 duration that is expected during the given recurrence interval.
"Surface impoundment" means a waste management unit which
					 is a natural topographic depression, excavation, or diked area, and which is
					 designed to contain liquid wastes or wastes containing free liquids, and which
					 is not an injection well.
"Tailings pond" means an excavated or diked area and which
					 is intended to contain liquid and solid wastes from mining and milling
					 operations.
"Transmissivity" means the rate at which water of the
					 prevailing kinematic viscosity is transmitted through a unit width of the
					 aquifer under a unit hydraulic gradient rate at which fluid will pass through a
					 given area of the saturated zone.
"Treatment" means any method, technique, or process
					 designed to change the physical, chemical, or biological characteristics of
					 waste so as to render it less harmful to the quality of the waters of the
					 state, safer to handle, easier to contain or manage, including use as fuel,
					 nutrient, or soil amendment.
"Treatment zone" means a soil area of the unsaturated zone
					 of a land treatment unit within which constituents of concern are degraded,
					 transformed, or immobilized.
"Underlying ground water," for the purposes of waste
					 management unit siting criteria, includes water which rises above the saturated
					 zone of saturation due to capillary forces.
"Unified Soil Classification System" means one of the
					 several generally accepted methods for soil identification and classification
					 for construction purposes presented in Geotechnical Branch Training Manuals No.
					 4, 5, and 6, published by the United States Bureau of Reclamation in January of
					 1986, which is hereby incorporated by reference (available from Bureau of
					 Reclamation, Engineering and Research Center, Attention: Code D-7923-A, P.O.
					 Box 25007, Denver, Colorado 80225).
"Unsaturated zone" means the underground zone in which not
					 all openings in and between natural geologic material are filled with water.
					 The zone may contain water and other liquids held by capillary forces, or
					 percolating liquids between the ground surface and the regional water table or,
					 in cases where the uppermost aquifer is confined, the zone between the ground
					 surface and the top of the saturated portion of the confining layer.
"Uppermost aquifer" means the geologic formation nearest
					 the natural ground surface that is an aquifer, as well as lower aquifers that
					 are hydraulically interconnected with this aquifer.
"Waste constituent" means a constituent that is reasonably
					 expected to be in or derived from waste contained in a waste management
					 unit.
"Waste management facility" or "facility" means the entire
					 parcel of property at which waste discharge operations are conducted. Such a
					 facility may include one or more waste management units.
"Waste management unit" means an area of land, or a portion
					 of a waste management facility, at which waste is discharged. The term includes
					 containment features and ancillary features for precipitation and drainage
					 control and monitoring.
"Waste pile" means a waste management unit at which only
					 noncontainerized, bulk, dry solid waste is discharged and piled on the land
					 surface.
"X Bar chart" means a control chart for evaluating the
					 process level or subgroup differences in terms of the subgroup average.
"Zone of saturation" means the subsurface zone extending
					 downward from the base of the unsaturated zone in which the interstices are
					 filled with water under pressure that is equal to or greater than atmospheric
					 pressure. Although the zone may contain gas-filled interstices or interstices
					 filled with fluids other than water, it is still considered saturated.
1. Amendment
					 of definitions of "Active life," "Attitude," "Background," "Capillary forces,"
					 "Constituent," "Discharger," "Ground rupture," "Ground water," "Landfill,"
					 "Land treatment unit," "land treatment facility," "Leachate," "Rapid geologic
					 change," "Statistically significant," "Transmissivity," "Underlying ground
					 water," "Unified Soil Classification System," "Unsaturated zone"; and new
					 definitions of "Affected medium," "Aquifer," "Background monitoring point,"
					 "Concentration limit," "Excess exposure," "Facility," "Hazardous constituent,"
					 "Independent sample," "Monitoring parameter," "Monitoring point," "Perched
					 ground water," "Physical parameter," "Point of compliance," "P-value," "R Chart
					 (range chart)," "Sensitive biological receptor of concern," "Treatment zone,"
					 "Uppermost aquifer," "Waste constituent," "X Bar chart," "Zone of saturation,"
					 filed 5-24-91; operative 7-1-91 (Register 91, No. 22).
2. Editorial
					 correction of Appendix II (Register 95, No. 43).
3. Amendment of
					 definitions of "Active life," "Classified waste management unit."
					 "Constituent," "Free liquid," "Ground water" and "Hazardous constituent"; new
					 definitions for "DTSC" and "Hazardous waste"; and repealer of Appendices II and
					 III filed 6-18-97; operative 7-18-97 (Register 97, No. 25).
Note: Authority cited: Section
						1058, Water
						Code, Reference: Section
						13172, Water
						Code.