Section 620.110  Definitions

 

The definitions of the Environmental Protection Act [415 ILCS 5] and the Groundwater Protection Act [415 ILCS 55] apply to this Part.  The following definitions also apply to this Part;

 

"Act" means the Environmental Protection Act [415 ILCS 5].

 

"Agency" means the Illinois Environmental Protection Agency.

 

"Aquifer" means saturated (with groundwater) soils and geologic materials that are sufficiently permeable to readily yield economically useful quantities of water to wells, springs, or streams under ordinary hydraulic gradients. [415 ILCS 55/3(b)]

 

"BETX" means the sum of the concentrations of benzene, ethylbenzene, toluene, and xylenes.

 

"Board" means the Illinois Pollution Control Board.

 

"Carcinogen" means a contaminant that is classified as a Category A1 or A2 Carcinogen by the American Conference of Governmental Industrial Hygienists; or a Category 1 or 2A/2B carcinogen by the World Health Organization's International Agency for Research on Cancer; or a "Human carcinogen" or "Anticipated Human Carcinogen" by the United States Department of Health and Human Service National Toxicological Program; or a Category A or B1/B2 Carcinogen or as "carcinogenic to humans" or "likely to become carcinogenic to humans" by the United States Environmental Protection Agency in Integrated Risk Information System or a Final Rule issued in a Federal Register notice by the USEPA. [415 ILCS 5/58.2]

 

"Chemical Abstracts Service Registry Number" or "CASRN" means a unique numerical identifier designated for only one substance, assigned by the Chemical Abstracts Service for the substance.

 

"Community water supply" means a public supply that serves or is intended to serve at least 15 service connections used by residents or regularly serves at least 25 residents. [415 ILCS 5/3.145]

 

"Contaminant" means any solid, liquid, or gaseous matter, any odor, or any form of energy, from whatever source. [415 ILCS 5/3.165]

 

"Corrective action process" means the procedures and practices that a regulatory agency may perform, require, or otherwise oversee, including corrective action and controls and management, to address a potential or existing violation of any Subpart D standard due to a release of one or more contaminants.

BOARD NOTE:  This definition includes the performance of activities that, under Section 620.450(a)(3), stay the applicability of otherwise applicable standards specified in Section 620.410, 620.420, 620.430, or 620.440.  This definition also includes the implementation of controls and management, under Section 620.250(d)(2) and (e), after the completion of corrective action.

 

"Cumulative impact area" means the area, including the coal mine area permitted under the Surface Coal Mining Land Conservation and Reclamation Act [225 ILCS 720] and 62 Ill. Adm. Code 1700 through 1850, within which impacts resulting from the proposed operation may interact with the impacts of all anticipated mining on surface water and groundwater systems.

 

"Detection" means the identification of a contaminant in a sample at a value equal to or greater than the:

 

"Method detection limit" or "MDL"; or

 

"Lower limit of quantitation" or "LLOQ".

 

"Groundwater" means underground water that occurs within the saturated zone and geologic materials where the fluid pressure in the pore space is equal to or greater than atmospheric pressure. [415 ILCS 5/3.210]

 

"Hydrologic balance" means the relationship between the quality and quantity of water inflow to, water outflow from, and water storage in a hydrologic unit, such as a drainage basin, aquifer, soil zone, lake, or reservoir.  It encompasses the dynamic relationships among precipitation, runoff, evaporation, and changes in ground and surface water storage.

 

"IGPA" means the Illinois Groundwater Protection Act.  [415 ILCS 55]

 

"Lower limit of quantitation" or "LLOQ" means the minimum concentration of a substance that can be measured or reported under "Test Methods of Evaluation Solid Wastes, Physical/Chemical Methods", incorporated by reference in Section 620.125.

 

"Lowest concentration minimum reporting level" or "LCMRL" means the lowest spiking concentration such that the probability of spike recovery in the 50% or 150% range is at least 99%.

 

"Lowest observable adverse effect level" or "LOAEL" means the lowest tested concentration of a chemical or substance that produces a statistically significant increase in frequency or severity of non-overt adverse effects between the exposed population and its appropriate control.

 

"Licensed Professional Engineer" or "LPE" means a person, corporation, or partnership licensed under the laws of the State of Illinois to practice professional engineering. [415 ILCS 5/57.2]

 

"Licensed Professional Geologist" or "LPG" means an individual who is licensed under the Professional Geologist Licensing Act to engage in the practice of professional geology in Illinois. [225 ILCS 745/15]

 

"Method detection limit" or "MDL" means the minimum measured concentration of a substance that can be reported with 99% confidence that the measured concentration is distinguishable from method blank results as determined under 40 CFR 136, appendix B (2017), incorporated by reference in Section 620.125.

 

"Mutagen" means a carcinogen that can induce an alteration in the structure of DNA.

 

"No observable adverse effect level" or "NOAEL" means the highest tested concentration of a chemical or substance that does not produce a statistically significant increase in frequency or severity of non-overt adverse effects between the exposed population and its appropriate control.

 

"Non-community water supply" means a public water supply that is not a community water supply. [415 ILCS 5/3.145]

 

"Off-site" means not on-site.

 

"On-site" means on the same or geographically contiguous property that may be divided by public or private right-of-way, if the entrance and exit between properties is at a crossroads 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 that he or she controls and that the public does not have access to is also considered on-site property.

 

"Operator" means the person responsible for the operation of a site, facility, or unit.

 

"Owner" means the person who owns a site, facility, or unit, or part of a site, facility, or unit, or who owns the land on which the site, facility, or unit is located.

 

"Potable" means generally fit for human consumption in compliance with accepted water supply principles and practices. [415 ILCS 5/3.340]

 

"Potential primary source" means any unit at a facility or site not currently subject to a removal or remedial action that:

 

Is used for the treatment, storage, or disposal of any hazardous or special waste not generated at the site; or

 

Is used for the disposal of municipal waste not generated at the site, other than landscape waste and construction and demolition debris; or

 

Is used for the landfilling, land treating, surface impounding, or piling of any hazardous or special waste that is generated on the site or at other sites owned, controlled, or operated by the same person; or

 

Stores or accumulates at any time more than 75,000 pounds above ground, or more than 7,500 pounds below ground, of any hazardous substances. [415 ILCS 5/3.345]

 

"Potential route" means abandoned and improperly plugged wells of all kinds, drainage wells, all injection wells, including closed loop heat pump wells, and any excavation for the discovery, development or production of stone, sand, or gravel. This term does not include closed loop heat pump wells using USP (U.S. Pharmacopeia) food grade propylene glycol. [415 ILCS 5/3.350]

 

"Potential secondary source" means any unit at a facility or a site not currently subject to a removal or remedial action, other than a potential primary source, that:

 

Is used for the landfilling, land treating, or surface impounding of waste that is generated on the site or at other sites owned, controlled, or operated by the same person, other than livestock and landscape waste, and construction and demolition debris; or

 

Stores or accumulates at any time more than 25,000 but not more than 75,000 pounds above ground, or more than 2,500 but not more than 7,500 pounds below ground, of any hazardous substance; or

 

Stores or accumulates at any time more than 25,000 gallons above ground, or more than 500 gallons below ground, of petroleum, including crude oil or any fraction of crude oil that is not otherwise specifically listed or designated as a hazardous substance; or

 

Stores or accumulates pesticides, fertilizers, or road oils for commercial application or for distribution to retail sales outlets; or

 

Stores or accumulates at any time more than 50,000 pounds of any de-icing agent; or

 

Is used for handling livestock waste or for treating domestic wastewaters other than private sewage disposal systems as defined in the Private Sewage Disposal Licensing Act [225 ILCS 225]. [415 ILCS 5/3.355]

 

"Previously mined area" means land disturbed or affected by coal mining operations before February 1, 1983.

BOARD NOTE:  February 1, 1983, is the effective date of the Illinois Department of Natural Resources Permanent Program regulations (62 Ill. Adm. Code 1800 through 1850) implementing the Surface Coal Mining Land Conservation and Reclamation Act [225 ILCS 720], as specified in 62 Ill. Adm. Code 1700.11(c).

 

"Property class" means the class assigned by a tax assessor to real property for real estate taxes.

BOARD NOTE:  The property class (rural property, residential vacant land, residential with dwelling, commercial residence, commercial business, commercial office, or industrial) is identified on the property record card maintained by the tax assessor in compliance with the Illinois Real Property Appraisal Manual (February 1987), published by the Illinois Department of Revenue, Property Tax Administration Bureau.

 

"Public water supply" means all mains, pipes, and structures through which water is obtained and distributed to the public, including wells and well structures, intakes and cribs, pumping stations, treatment plants, reservoirs, and storage tanks and appurtenances, collectively or severally, actually used or intended for use for furnishing water for drinking or general domestic use, and that serve at least 15 service connections or that regularly serve at least 25 persons at least 60 days per year.  A public water supply is either a "community water supply" or a "non-community water supply". [415 ILCS 5/3.365]

 

"Regulated entity" means a facility or unit regulated for groundwater protection by any State or federal agency.

 

"Regulated recharge area" means a compact geographic area, as determined by the Board under Section 17.4 of the Act, the geology of which renders a potable resource groundwater particularly susceptible to contamination. [415 ILCS 5/3.390]

 

"Regulatory agency" means the Illinois Environmental Protection Agency, Department of Public Health, Department of Agriculture, the Office of Mines and Minerals and the Office of Oil and Gas Resource Management in the Department of Natural Resources, and the Office of State Fire Marshal.

 

"Resource groundwater" means groundwater that is presently being, or in the future is capable of being, put to beneficial use by reason of being of suitable quality. [415 ILCS 5/3.430]

 

"Saturated zone" means a subsurface zone in which all the interstices or voids are filled with water under pressure greater than that of the atmosphere. 

 

"Setback zone" means a geographic area, designated under the Act, containing a potable water supply well or a potential source or potential route having a continuous boundary, and within which specified prohibitions or regulations apply to protect groundwaters. [415 ILCS 5/3.450]

 

"Site" means any location, place, tract of land, and facilities, including buildings and improvements used for purposes subject to regulation or control by the Act or regulations under the Act. [415 ILCS 5/3.460]

 

"Spring" means a natural surface discharge of an aquifer from rock or soil.

 

"Threshold dose" means the lowest dose of a chemical at which a specified measurable effect is observed and below which it is not observed.

 

"Treatment" means the technology, treatment techniques, or other procedures for compliance with 35 Ill. Adm. Code, Subtitle F.

 

"Unit" means any device, mechanism, equipment, or area (exclusive of land used only for agricultural production). This term includes secondary containment structures and their contents at agrichemical facilities.  [415 ILCS 5/3.515]

 

"USEPA" means the United States Environmental Protection Agency.

 

"Wellhead protection area" or "WHPA" means the surface and subsurface recharge area surrounding a community water supply well or well field, delineated outside of any applicable setback zones under Section 17.1 of the Act [415 ILCS 5/17.1] and Illinois' Wellhead Protection Program, through which contaminants are reasonably likely to move toward that well or well field.

 

"Wellhead Protection Program" or "WHPP" means the wellhead protection program for the State of Illinois, approved by USEPA under 42 U.S.C. 300h-7.

BOARD NOTE:  Derived from 40 CFR 141.71(b) (2003).  The wellhead protection program includes the "groundwater protection needs assessment" under Section 17.1 of the Act [415 ILCS 5/17.1] and 35 Ill. Adm. Code 615-617.

 

(Source:  Amended at 49 Ill. Reg. 4488, effective March 28, 2025)