Part 301: INTRODUCTION

Section 301.341 Pollutant Minimization Program "Pollutant Minimization Program" means a structured set of activities to improve processes and pollutant controls that will prevent and reduce pollutant loading. (Source: Amended at 47 Ill. Reg. 4415, effective March 23, 2023)

Section 301.345 Population Equivalent "Population Equivalent" is a term used to evaluate the impact of industrial or other waste on a treatment works or stream. One population equivalent is 100 gallons (380 l) of sewage per day, containing 0.17 pounds (77 g) of BOD5 (five day bio…

Section 301.346 Preliminary Effluent Limitation "Preliminary Effluent Limitation" or "PEL" is an estimate of an allowable discharge considering mixing or dilution. (Source: Amended at 47 Ill. Reg. 4415, effective March 23, 2023)

Section 301.350 Pretreatment Works "Pretreatment Works" means a treatment works designed and intended to treat wastewater from an indirect discharge or industrial user as defined in 40 CFR 403 (2022) before it is introduced into a sewer system tributary to a publicly owned or pub…

Section 301.355 Primary Contact "Primary Contact" means any recreational or other water use in which there is prolonged and intimate contact with the water involving considerable risk of ingesting water in quantities sufficient to pose a significant health hazard, such as swimmin…

Section 301.356 Projected Effluent Quality "Projected Effluent Quality" or "PEQ" is the amount of a contaminant estimated to be discharged by a facility or activity considering a statistical analysis of the discharge or activity. (Source: Amended at 47 Ill. Reg. 4415, effective M…

Section 301.360 Public and Food Processing Water Supply "Public and Food Processing Water Supply" means any water use in which water is withdrawn from surface waters of the State for human consumption or for processing of food products intended for human consumption.

Section 301.365 Publicly Owned Treatment Works "Publicly Owned Treatment Works" means a treatment works owned by a municipality, sanitary district, county, or state agency, and which treats domestic and industrial wastes collected by a publicly owned or regulated sewer system. In…

Section 301.370 Publicly Regulated Treatment Works "Publicly Regulated Treatment Works" means otherwise private companies that are regulated as public utilities engaged in the disposal of domestic and industrial wastes and regulated by the Illinois Commerce Commission under the P…

Section 301.371 Quantification Level "Quantification Level" is a measurement of the concentration of a contaminant obtained by using a specified laboratory procedure calibrated at a specified concentration above the method detection level. It is considered the lowest concentratio…

Section 301.372 Reasonable Potential Analysis "Reasonable Potential Analysis" or "Reasonable Potential to Exceed" means the procedure to predict whether an existing or future discharge would cause or contribute to a violation of water quality standards, criteria or values. (Sourc…

Section 301.373 Same Body of Water "Same Body of Water" means that, for purposes of evaluating intake toxic substances consistent with 35 Ill. Adm. Code 352.425, the Agency will consider intake toxic substances to be from the same body of water if the Agency finds that the intake…

Section 301.375 Sanitary Sewer "Sanitary Sewer" means a sewer that carries wastewater together with incidental land runoff. (Source: Amended at 3 Ill. Reg. 25, page 190, effective June 21, 1979)

Section 301.380 Secondary Contact "Secondary Contact" means any recreational or other water use in which contact with the water is either incidental or accidental and in which the probability of ingesting appreciable quantities of water is minimal, such as fishing, commercial and…

Section 301.385 Sewage "Sewage" means water-carried human and related wastes from any source. (Source: Amended at 3 Ill. Reg. 25 page 190, effective June 21, 1979)

Section 301.390 Sewer "Sewer" means a stationary means of transport or stationary system of transport, excluding natural waterways, constructed and operated for the purpose of collecting and transporting wastewater or land runoff, or both. (Source: Amended at 3 Ill. Req. 25 page …

Section 301.395 Sludge "Sludge" means any solid, semisolid, or liquid waste generated from a municipal, commercial, or industrial wastewater treatment plant, water supply treatment plant, or air pollution control facility, or any other waste having similar characteristics and eff…

Section 301.400 Standard of Performance "Standard of Performance" means a standard promulgated by the Administrator under Section 306 of the CWA for the control of the discharge of pollutants reflecting the greatest degree of effluent reduction that the Administrator determines t…

Section 301.405 STORET "STORET" means the national water quality data system of the federal Environmental Protection Agency.

Section 301.410 Storm Sewer "Storm Sewer" means a sewer intended to receive only land runoff.

Section 301.411 Total Maximum Daily Load "Total Maximum Daily Load" or "TMDL" is the sum of the individual wasteload allocations for point sources and load allocations for nonpoint sources and natural background, as more fully defined at 40 CFR 130.2(i). A TMDL sets and allocates…

Section 301.413 Total Metal "Total Metal" means the dissolved fraction of metal in a solution plus the suspended fraction. (Source: Added at 27 Ill. Reg. 158, effective December 20, 2002)

Section 301.415 Treatment Works "Treatment Works" means individually or collectively those constructions or devices (except sewers, and except constructions or devices used for the pretreatment of wastewater prior to its introduction into publicly owned or regulated treatment wor…

Section 301.420 Underground Waters "Underground Waters" means any waters of the State located beneath the surface of the earth.

Section 301.421 Wasteload Allocation "Waste Load Allocation" or "WLA" is the portion of receiving water's loading capacity that is allocated to one of its existing or future point sources of pollution, as more fully defined at 40 CFR 130.2(h). In the absence of a TMDL approved by…

Section 301.425 Wastewater "Wastewater" means sewage, industrial waste, or other waste, or any combination of these, whether treated or untreated, plus any admixed land runoff.

Section 301.430 Wastewater Source "Wastewater Source" means any equipment, facility, or other source of any type that discharges wastewater, directly or indirectly to the waters of the State. (Source: Amended at 47 Ill. Reg. 4415, effective March 23, 2023)

Section 301.435 Watercraft "Watercraft" means every type of boat, ship or barge used or capable of being used as a means of transportation on water.

Section 301.440 Waters "Waters" means all accumulations of water, surface and underground, natural, and artificial, public and private, or parts thereof, which are wholly or partially within, flow through, or border upon the State of Illinois, except that sewers and treatment wor…

Section 301.441 Water Quality Based Effluent Limitation "Water Quality Based Effluent Limitation" or "WQBEL" is a limit imposed in a permit so that the applicable water quality standard, criteria or value is not exceeded outside of a designated mixing zone. (Source: Amended at 47…

Section 301.442 Wet Weather Point Source "Wet Weather Point Source" means any discernible, confined, and discrete conveyance from which pollutants are, or may be, discharged as the result of a wet weather event. Discharges from wet weather point sources must include only: dischar…

Section 301.443 Whole Effluent Toxicity "Whole Effluent Toxicity" or "WET" means a test procedure that determines the effect of an effluent on aquatic life. (Source: Amended at 47 Ill. Reg. 4415, effective March 23, 2023)

Section 301.APPENDIX A References to Previous Rules (Repealed) (Source: Repealed at 47 Ill. Reg. 4415, effective March 23, 2023)