# 35 Ill. Adm. Code 310.110: Section 310.110 Definitions > Illinois · Regulations · In force URL: https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_110 ## Section - **Citation:** 35 Ill. Adm. Code 310.110 - **Heading:** Section 310.110 Definitions - **Jurisdiction:** Illinois - **Kind:** Regulations - **Status:** In force - **Text as of:** August 14, 2026 - **Source:** Compiled text - **Location:** Illinois Administrative Code / Title 35 ENVIRONMENTAL PROTECTION / CHAPTER I: POLLUTION CONTROL BOARD / Part 310 PRETREATMENT PROGRAMS / Section 310.110 Definitions ## Text Section 310 Section 310.110  Definitions The following definitions, derived from the general definitions of 40 CFR 401.11 and the pretreatment-specific definitions of 40 CFR 403.3, apply to this Part and 35 Ill. Adm. Code 307: "Act" means the Environmental Protection Act [415 ILCS 5]. "Agency" means the Illinois Environmental Protection Agency. BOARD NOTE:  The Board has consistently rendered "Director", as defined in corresponding 40 CFR 403.3(g), as "Agency" for all functions within the Agency's statutory authority and that USEPA has not clearly reserved the function to itself. "Approval Authority" means the Agency after USEPA has approved the Illinois wastewater pretreatment program.  "Approval Authority" means USEPA before USEPA approval of the Illinois wastewater pretreatment program. BOARD NOTE: Derived from 40 CFR 403.3(c) (2016). "Approved POTW pretreatment program" or "program" or "POTW pretreatment program" means a program administered by a POTW that has been approved by USEPA, under 40 CFR 403.11, or the Agency, in accordance with Sections 310.541 through 310.546. BOARD NOTE: Derived from 40 CFR 403.3(d) (2016). "Authorization to discharge" means an authorization issued to an industrial user by a POTW that has an approved pretreatment program.  The authorization may consist of a permit, license, ordinance, or another mechanism specified in the approved pretreatment program. BOARD NOTE: The Board added this term to distinguish a "pretreatment permit," which is a control mechanism issued by the Agency. "Best management practices" or "BMPs" means schedules of activities, prohibitions of practices, maintenance procedures, and other management practices to implement the prohibitions listed in Sections 310.201(a) and (c) and 310.202.  BMPs also include treatment requirements, operating procedures, and practices to control plant site runoff, spillage or leaks, sludge or waste disposal, or drainage from raw materials storage. BOARD NOTE:  Derived from 40 CFR 403.3(e) (2016) s of practices, maintenance procedures, and other management practices to implement the prohibitions listed in Sections 310.201(a) and (c) and 310.202.  BMPs also include treatment requirements, operating procedures, and practices to control plant site runoff, spillage or leaks, sludge or waste disposal, or drainage from raw materials storage. BOARD NOTE:  Derived from 40 CFR 403.3(e) (2016). "Blowdown" means the minimum discharge of recirculating water for discharging materials contained in the water, the further buildup of which would cause concentration in amounts exceeding limits established by best engineering practice. BOARD NOTE: Derived from 40 CFR 401.11(p) (2016). "Board" means the Illinois Pollution Control Board. BOARD NOTE:  The Board has consistently rendered "Director," as defined in corresponding 40 CFR 403.3(g), as "Board" for all functions within the Board's statutory authority and for which USEPA has not clearly reserved the function to itself. "CWA" means Federal Water Pollution Control Act, also known as the Clean Water Act, as amended (33 U.S.C. 1251 et seq.). BOARD NOTE: Derived from 40 CFR 403.3(b) (2016). "Control Authority" refers to the appropriate of the following: The POTW, if the POTW's pretreatment program submission has been approved by the Agency, in accordance with the requirements of Sections 310.541 through 310.546 or by USEPA in accordance with 40 CFR 403.11; or The Approval Authority, if no pretreatment program submission has yet been approved. BOARD NOTE:  Derived from 40 CFR 403.3(f) (2016). "Existing source" means any building, structure, facility, or installation from which there is or may be a discharge of pollutants, the construction of which occurred before the date that would qualify the building, structure, facility, or installation for definition as a "new source", as defined in Section 310.111 ssion has yet been approved. BOARD NOTE:  Derived from 40 CFR 403.3(f) (2016). "Existing source" means any building, structure, facility, or installation from which there is or may be a discharge of pollutants, the construction of which occurred before the date that would qualify the building, structure, facility, or installation for definition as a "new source", as defined in Section 310.111. BOARD NOTE:  The Board added this definition of a fundamental term that is used throughout the categorical standards to determine the applicability of those standards. "Indirect discharge" or "discharge" means the introduction of pollutants into a POTW from any non-domestic source regulated under section 307(b), (c), or (d) of the CWA (33 U.S.C. 1317 (b), (c), or (d)), incorporated by reference in Section 310.107. BOARD NOTE: Derived from 40 CFR 403.3(i) (2016). "Industrial user" or "user" means a source of an indirect discharge. BOARD NOTE: Derived from 40 CFR 403.3(j) (2016). "Industrial wastewater" means the spent or used water containing dissolved or suspended matter discharged by an industrial user to a sewer tributary to a POTW. "Interference" means a discharge, alone or in conjunction with a discharge or discharges from other sources, for which both of the following are true: The discharge inhibits or disrupts the POTW, its treatment processes or operations, or its sludge processes, use, or disposal; and As a result of the inhibition or disruption, the discharge is a cause of a violation of any requirement of the POTW's NPDES permit (including an increase in the magnitude or duration of a violation) or the prevention of sewage sludge use or disposal in compliance with applicable laws and permits issued under those laws, including 33 U.S.C. 405 and 40 CFR 503 (federal standards for sewage sludge use and disposal) and State standards relating to sludge use and disposal (such as 415 ILCS 5/21 and 22.56a and 35 Ill. Adm. Code 309.155, 309.208, and 391), 42 U.S.C. 6901 et seq of a violation) or the prevention of sewage sludge use or disposal in compliance with applicable laws and permits issued under those laws, including 33 U.S.C. 405 and 40 CFR 503 (federal standards for sewage sludge use and disposal) and State standards relating to sludge use and disposal (such as 415 ILCS 5/21 and 22.56a and 35 Ill. Adm. Code 309.155, 309.208, and 391), 42 U.S.C. 6901 et seq. (the federal Resource Conservation and Recovery Act (hazardous waste and municipal solid waste disposal requirements)) and 35 Ill. Adm. Code: Subtitle G derived from the federal solid waste and hazardous waste management standards, 42 U.S.C. 7401 et seq. (the federal Clean Air Act) and 35 Ill. Adm. Code:  Subtitle B derived from the federal Clean Air Act standards, 53 U.S.C. 2601 et seq. (the federal Toxic Substances Control Act) or any Illinois requirements relating to toxic substances (such as 415 ILCS 5/21 and 35 Ill. Adm. Code 742, 807, and 810), and 33 U.S.C. 1401 et seq. (the federal Marine Protection, Research, and Sanctuaries Act). BOARD NOTE: Derived from 40 CFR 403.3(k) (2016). "Municipality". See "unit of local government". "New source" means a new source as defined in Section 310.111. BOARD NOTE: Derived from 40 CFR 401.11(e) and 403.3(m) (2016). "Noncontact cooling water" means water used for cooling that does not come into direct contact with any raw material, intermediate product, waste product, or finished product. BOARD NOTE: Derived from 40 CFR 401.11(n) (2016). "Noncontact cooling water pollutants" means pollutants present in noncontact cooling waters. BOARD NOTE: Derived from 40 CFR 401.11(o) (2016). "NPDES permit" means a permit issued to a POTW under Section 402 of the CWA or Section 12(f) of the Act and Subpart A of 35 Ill. Adm. Code 309. BOARD NOTE: Derived from 40 CFR 403.3(n) (2016) duct. BOARD NOTE: Derived from 40 CFR 401.11(n) (2016). "Noncontact cooling water pollutants" means pollutants present in noncontact cooling waters. BOARD NOTE: Derived from 40 CFR 401.11(o) (2016). "NPDES permit" means a permit issued to a POTW under Section 402 of the CWA or Section 12(f) of the Act and Subpart A of 35 Ill. Adm. Code 309. BOARD NOTE: Derived from 40 CFR 403.3(n) (2016). "Pass through" means a discharge of pollutants that exits the POTW into waters of the State in quantities or concentrations which, alone or in conjunction with a discharge or discharges from other sources, is a cause of a violation of any requirement of the POTW's NPDES permit (including an increase in the magnitude or duration of a violation). BOARD NOTE: Derived from 40 CFR 403.3(p) (2016). "Person" means an individual, corporation, partnership, association, State, unit of local government, commission, or any interstate body.  This term includes the United States government, the State of Illinois, and their political subdivisions. BOARD NOTE: Derived from 40 CFR 401.11(m) (2016) and 33 U.S.C. 1362(5) (2014). "Point source" means any discernible, confined, and discrete conveyance, including any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, container, rolling stock, concentrated animal feeding operation, or vessel or other floating craft, from which pollutants are or may be discharged. BOARD NOTE:  Derived from 40 CFR 401.11(d) (2016). "Pollutant" means dredged spoil; solid waste; incinerator residue; sewage; garbage; sewage sludge; munitions; chemical wastes; biological materials; radioactive materials; heat; wrecked or discarded equipment; rock; sand; cellar dirt; and industrial, municipal, and agricultural waste discharged into a sewer. BOARD NOTE: Derived from 40 CFR 401.11(f) (2016). "Pollution" means the man-made or man-induced alteration of the chemical, physical, biological, and radiological integrity of water. BOARD NOTE: Derived from 40 CFR 401.11(g) (2015) radioactive materials; heat; wrecked or discarded equipment; rock; sand; cellar dirt; and industrial, municipal, and agricultural waste discharged into a sewer. BOARD NOTE: Derived from 40 CFR 401.11(f) (2016). "Pollution" means the man-made or man-induced alteration of the chemical, physical, biological, and radiological integrity of water. BOARD NOTE: Derived from 40 CFR 401.11(g) (2015). "POTW treatment plant" means that portion of the POTW that is designed to provide treatment (including recycling and reclamation) of municipal sewage and industrial wastewater. BOARD NOTE: Derived from 40 CFR 403.3(r) (2016). "Pretreatment" means the reduction of the amount of pollutants, the elimination of pollutants, or the alteration of the nature of pollutant properties in wastewater prior to or in lieu of discharging or otherwise introducing such pollutants into a POTW.  The reduction or alteration may be obtained by physical, chemical, or biological processes; process changes; or by other means, except as prohibited by Section 310.232.  Appropriate pretreatment technology includes control equipment, such as equalization tanks or facilities, for protection against surges or slug loadings that might interfere with or otherwise be incompatible with the POTW. However, if wastewater from a regulated process is mixed in an equalization facility with unregulated wastewater or with wastewater from another regulated process, the effluent from the equalization facility must meet an adjusted pretreatment limit calculated in accordance with Section 310.233. BOARD NOTE: Derived from 40 CFR 403.3(s) (2016). "Pretreatment permit" means a permit to discharge to a sewer that is issued by the Agency as the Control Authority. BOARD NOTE:  The Board added this term to distinguish an "authorization to discharge," which is a control mechanism issued by a POTW cility must meet an adjusted pretreatment limit calculated in accordance with Section 310.233. BOARD NOTE: Derived from 40 CFR 403.3(s) (2016). "Pretreatment permit" means a permit to discharge to a sewer that is issued by the Agency as the Control Authority. BOARD NOTE:  The Board added this term to distinguish an "authorization to discharge," which is a control mechanism issued by a POTW. "Pretreatment requirement" means any substantive or procedural requirement related to pretreatment imposed on an industrial user by a pretreatment permit or lawful order, other than a pretreatment standard. BOARD NOTE: Derived from 40 CFR 403.3(t) (2016). "Pretreatment standard" or "standard" means any regulation containing pollutant discharge limits promulgated by USEPA, and incorporated by reference in 35 Ill. Adm. Code 307.  This term includes prohibitive discharge limits established under Sections 310.201 through 310.213 or 35 Ill. Adm. Code 307.1101.  This term also includes more stringent prohibitions and standards adopted by the Board in this Part or 35 Ill. Adm. Code 307, including 35 Ill. Adm. Code 307.1101, 307.1102, and 307.1103. The term also includes local limits that are a part of an approved pretreatment program, as provided in Section 310.211. BOARD NOTE: Derived from 40 CFR 403.3(l) (2016). "Process wastewater" means any water that, during manufacturing or processing, comes into direct contact with or results from the production or use of any raw material, intermediate product, finished product, by-product, or waste product. BOARD NOTE: Derived from 40 CFR 401.11(q) (2016). "Process wastewater pollutants" means pollutants present in process wastewater. BOARD NOTE: Derived from 40 CFR 401.11(r) (2016) ns any water that, during manufacturing or processing, comes into direct contact with or results from the production or use of any raw material, intermediate product, finished product, by-product, or waste product. BOARD NOTE: Derived from 40 CFR 401.11(q) (2016). "Process wastewater pollutants" means pollutants present in process wastewater. BOARD NOTE: Derived from 40 CFR 401.11(r) (2016). "Publicly owned treatment works" or "POTW" means a "treatment works" that is owned by the State of Illinois or a "unit of local government." This definition includes any devices and systems used in the storage, treatment, recycling, and reclamation of municipal sewage or industrial wastewater.  It also includes sewers, pipes, and other conveyances only if they convey wastewater to a POTW treatment plant.  The term also means the "unit of local government" that has jurisdiction over the indirect discharges to and the discharges from such a treatment works. BOARD NOTE: Derived from 40 CFR 403.3(q) (2016). "Schedule of compliance" means a schedule of remedial measures included in an authorization to discharge or a pretreatment permit, or an NPDES permit, including an enforceable sequence of interim requirements (for example, actions, operations, or milestone events) leading to compliance with this Part and 35 Ill. Adm. Code 307.  A schedule of compliance does not protect an industrial user or POTW from enforcement. BOARD NOTE: Derived from 40 CFR 401.11(m) (2016) and 33 U.S.C. 1362(17). "Significant industrial user" means significant industrial user as defined in Section 310.112. BOARD NOTE: Derived from 40 CFR 403.3(v) (2016). "Sludge requirements" means any of the following permits or regulations:   35 Ill. Adm A schedule of compliance does not protect an industrial user or POTW from enforcement. BOARD NOTE: Derived from 40 CFR 401.11(m) (2016) and 33 U.S.C. 1362(17). "Significant industrial user" means significant industrial user as defined in Section 310.112. BOARD NOTE: Derived from 40 CFR 403.3(v) (2016). "Sludge requirements" means any of the following permits or regulations:   35 Ill. Adm. Code 309.155 (NPDES Permits), 309.208 (Permits for Sites Receiving Sludge for Land Application), 703.121 (RCRA Permits), 807.202 (Solid Waste Permits); Section 39(b) of the Act (NPDES Permits); Section 405(b) of the federal Clean Water Act (federally-imposed sludge use and management requirements); and 40 CFR 501 and 503. BOARD NOTE:  Derived from 40 CFR 403.3(k)(2) and 403.7(a) (2016). "Submission" means a request to the Agency by a POTW for approval of a pretreatment program, or for authorization to grant removal credits. BOARD NOTE:  Derived from 40 CFR 403.3(w) (2016). "Treatment works" is as defined in 33 U.S.C. 1292(2), incorporated by reference in Section 310.107.  It includes any devices and systems used in the storage, treatment, recycling, and reclamation of municipal or industrial wastewater to implement 33 U.S.C. 1281, or necessary to recycle or reuse water at the most economical cost over the estimated life of the works, including intercepting sewers, outfall sewers, sewage collection systems, pumping, power, and other equipment. BOARD NOTE:  Derived from 40 CFR 403.3(q) (2016) and 33 U.S.C. 1292(2). "Unit of local government" means a unit of local government, as defined by Art. 7, Sec. 1 of the Illinois Constitution.  Unit of local government includes municipalities and sanitary districts. BOARD NOTE:  Derived from 40 CFR 401.11(m) (2016) and 33 U.S.C. 1362(4). "USEPA" means the United States Environmental Protection Agency. ## Nearby sections - [35 Ill. Adm. Code 310.101 Section 310.101 Applicability](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_101.md) - [35 Ill. Adm. Code 310.102 Section 310.102 Objectives](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_102.md) - [35 Ill. Adm. Code 310.103 Section 310.103 Federal Law](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_103.md) - [35 Ill. Adm. Code 310.104 Section 310.104 State Law](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_104.md) - [35 Ill. Adm. Code 310.105 Section 310.105 Confidentiality](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_105.md) - [35 Ill. Adm. Code 310.107 Section 310.107 Incorporations by Reference](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_107.md) - [35 Ill. Adm. Code 310.110 Section 310.110 Definitions](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_110.md) - [35 Ill. Adm. Code 310.111 Section 310.111 New Source](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_111.md) - [35 Ill. Adm. Code 310.112 Section 310.112 Significant Industrial User](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_112.md) --- Source: Frix Law Library, https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_110. Check the current official text before relying on it. Not legal advice.