Water and Pollution Control Department

Pretreatment Program Definitions

Act: Federal Water Pollution Control Act, also known as the Clean Water Act, as amended, 33 U.S.C. 1251, et seq.
Authorized Representative: Highest official appointed or designated responsibility of operation and performance of the facility. May be a corporate officer, partner, or duly authorized representative of such in accordance with 40 CFR 403.12 (l).
Biosolids: Also known as sewage sludge; treated and stabilized solids, semi-solid, or liquid residue generated during the treatment of domestic wastewater at the POTW.
Categorical Industry or Facility: Classification of industries or facilities which must meet specific federal discharge limits set by EPA. Categorical status is determined by EPA.
CBOD5: (denoting 5-day Carbonaceous Biochemical Oxygen Demand) The quantity of oxygen used in the biochemical oxidation of organic matter under standard laboratory procedure in five days at 20oC, expressed in milligrams per liter (mg/L).
CFR: Code of Federal Regulations
City: City of Ames, Iowa
Civil Action: Legal action taken by the City to require compliance with the Code; may seek injunction and/or cease and desist order.
COD: (denoting Chemical Oxygen Demand) The oxygen equivalent of the organic matter content of a sample that is susceptible to oxidation by a strong chemical oxidant as determined by standard laboratory procedures for COD, expressed in milligrams per liter (mg/L).
Code: City of Ames, Iowa Municipal Code.
Composite Sample: A time-based or flow-proportional sample (as determined by the Water and Pollution Control Department staff) that is representative of a user’s or contributor’s typical work day discharge during a 24-hour period.
Contributor: Any entity that discharges wastewater into the City of Ames sanitary sewer system.
Director: The Director of the Ames Water and Pollution Control Department or any member of the Water and Pollution Control Department staff designated to act in the director’s behalf.
Discharge: Wastewater which is released into the city sanitary sewer system.
Domestic Wastewater: Wastewater resulting from residential dwellings or households. Typical or normal domestic wastewater has the following average maximum strength concentrations
	CBOD5: 250 mg/L
	COD: 550 mg/L
	TSS: 300 mg/L
	NH3: 30 mg/L
	TKN: 45 mg/L
FOG: Acronym for Fats, Oils, and Greases
Grab Sample: A sample taken from a waste stream on a one-time basis without regard to flow or consideration of time of day.
Interference: A discharge which, alone or in conjunction with a discharge or discharges from other sources:
inhibits or disrupts the POTW, its treatment processes or operations, or its sludge processes, use or disposal; and 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 of the prevention of sewage sludge use or disposal in compliance with the following statutory provisions and regulations or permits issued thereunder (or more stringent State or local regulations): Section 405 of the Clean Water Act, the Solid Waste Disposal Act (SWDA) (including title II, more commonly referred to as the Resource Conservation and Recovery Act (RCRA), and including State regulations contained in any State sludge management plan prepared pursuant to subtitle D of the SWDA), the Clean Air Act, the Toxic Substances Control Act, and the Marine Protection, Research and Sanctuaries Act.
Local Discharge Limits: Discharge limits for local facilities based on POTW headworks calculations and/or sanitary sewer worker safety.
Minor Non-Domestic Contributor or User: A contributor of non-domestic wastewater that is required to have a pretreatment permit. The need for a permit is determined based on a case-by-case evaluation of the quantity and quality of the contributor’s wastewater and the potential for discharging wastes of a non-domestic nature.
Municipal Infraction: A type of civil action taken by the City to ensure compliance with the Municipal Code. For pretreatment, a penalty of up to $1,000 per day per violation for the first and each subsequent violation or incidence of non-compliance may be assessed to the non-compliant entity.
NPDES: Acronym for National Pollutant Discharge Elimination System
NAICS: Acronym for North American Industry Classification System, the industry classification system used by the statistical agencies of the United States. NAICS replaces the 1987 Standard Industrial Classification (SIC).
New Source: New Source means any building, structure, facility, or installation from which there is or may be a Discharge of pollutants, the construction of which commenced after the publication of proposed Pretreatment Standards under Section 307(c) of the Act which will be applicable to such source if such Standards are thereafter promulgated in accordance with that section, provided that:
the building, structure, facility, or installation is constructed at a site at which no other source is located; or the building, structure, facility, or installation totally replaces the process or production equipment that causes the discharge of pollutants at an existing source; or the production or wastewater generating processes of the building, structure, facility, or installation are substantially independent of an existing source at the same site. In determining whether these are substantially independent, factors such as the extent to which the new facility is integrated with the existing plant and the extent to which the new facility is engaged in the same general type of activity as the existing source should be considered.
Non-Domestic Contributor or User: Any person or entity that discharges wastewater to the Ames sanitary sewer system which originates from other than typical domestic or household sources.
Non-Domestic Wastewater: Wastewater that contains concentrations that are higher than or that have substantially different ratios of pollutants that define typical domestic wastewater and/or any other substances attributable to industrial, commercial, agricultural, research or other non-residential activities.
Notice of Violation: A verbal or written notice given by the City to a contributor notifying the entity that a violation of the pretreatment regulation, the Code, or the permit has occurred.
Pass-Through: A discharge which exits the POTW into waters of the United States 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).
pH: A measure of the acidity or alkalinity of a substance; expressed in standard units.
POTW: An acronym for Publicly Owned Treatment Works; a treatment works as defined by Section 212 of the Act, which is owned by a state or municipality (as defined by Section 502(4) of the Act). This definition includes any devices and systems used for the collection, storage, treatment, recycling, and reclamation of municipal sewage, domestic sewage, or liquid industrial wastes. These include intercepting sewers, outfall sewers, sewage collection systems, pumping, power, and other equipment and their appurtenances; extensions, improvement, remodeling, additions, and alterations thereof; elements essential to provide a reliable recycled supply such as standby treatment units and clear well facilities; and any works, including site acquisition of the land that will be an integral part of the treatment process or is used for ultimate disposal of residues resulting from such treatment (including land for composting biosolids, temporary storage of such compost, and land used for the storage of treated wastewater in land treatment systems before land application); or any other method or system for preventing, abating, reducing, storing, treating, separating, or disposing of municipal or industrial wastewater. The term also means the municipality as defined in Section 502(4) of the Act, which has jurisdiction over the Indirect Discharges to and the discharges from such a treatment works.
POTW Treatment Facility: That portion of the POTW which is designed to provide treatment (including recycling and reclamation) of municipal sewage and industrial waste.
Pretreatment: 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 §403.6(d) [No dilution allowed.]. 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.
Pretreatment Program: The document approved by the Iowa Department of Natural Resources and the Ames City Council outlining requirements of the federal pretreatment requirements and detailing the procedures used by the City of Ames to implement and comply with the federal requirements.
Residential or Domestic Contributor or User: Any person or entity contributing wastewater to the Ames POTW whose lot, parcel or real estate, or building is used for domestic dwelling purposes only.
Sewer Surcharge: A user charge system adopted in the city’s sewer use ordinance to recover the actual cost of treating wastewater that is higher in concentration than typical or normal domestic wastewater for CBOD5, COD, TSS, NH3, or TKN.
Significant Industrial User, Significant Non-Domestic Contributor, or SIU: Defined in the EPA federal regulations (40 CFR 403.3(v)) as any contributor to the municipal sanitary sewer system which:
is subject to Categorical Pretreatment Standards under 40 CFR 403.6 and 40 CFR chapter I, subchapter N; or discharges an average of 25,000 gallons per day or more of process wastewater to the Publicly Owned Treatment Works (POTW), excluding sanitary, non-contact cooling, and boiler blowdown wastewater; or contributes a process waste stream which makes up five percent or more of the average dry-weather hydraulic or organic capacity of the POTW; or is designated as such by the City on the basis that the contributor has a reasonable potential to adversely affect the POTW’s operation or for violating any pretreatment standard or requirement.
Significant Non-Compliance: A violation that meets one or more of the following criteria as listed in 40CFR 403.8(f)(2)(viii).
Chronic violations of wastewater discharge limits, defined here as those in which 66 percent or more of all of the measurements taken during a six-month period exceed (by any magnitude) the daily maximum limit or the average limit for the same pollutant parameter Technical Review Criteria (TRC) violations, defined here as those in which 33 percent or more of all of the measurements for each pollutant parameter taken during a six-month period equal or exceed the product of the daily maximum limit or the average limit multiplied by the applicable TRC (TRC=1.4 for BOD, TSS, fats, oil, and grease and 1.2 for all other pollutants except pH Any other violation of a pretreatment effluent limit (daily maximum or longer-term average) that the City determines has caused, alone or in combination with other discharges, interference or pass-through (including endangering the health of POTW personnel or the general public) Any discharge of a pollutant that has caused imminent endangerment to human health, welfare, or the environment or has resulted in the POTW's exercise of its emergency authority to halt or prevent such a discharge Failure to meet, within 90 days after the schedule date, a compliance schedule milestone contained in a pretreatment permit or enforcement order for starting construction, completing construction, or attaining final compliance Failure to provide, within 30 days after the due date, required reports such as baseline monitoring reports, 90-day compliance reports, periodic self-monitoring reports, and reports on compliance with compliance schedules Failure to accurately report non-compliance Any other violation or group of violations which the City determines will adversely affect the operation or implementation of the local pretreatment program
Slug Discharge: Any discharge of a non-routine, episodic nature, including, but not limited to, an accidental spill or a non-customary batch discharge.
Standard Industry Classification (SIC) Code: A classification pursuant to the Standard Industrial Classification Manual issued by the U.S. Office of Management and Budget. Has been replaced by the North American Industry Classification System (NAICS).
Total Suspended Solids (TSS): Solids that either float on the surface or are in suspension in water, sewage, or other liquids and which are removable by standard laboratory filtering procedures, as expressed in milligrams per liter (mg/L).
Violation: Any instance of non-compliance (regardless of fault, negligence, or intent on the part of the contributor) with the requirements of the pretreatment program, any contract, federal or state law or regulation, or permit issued. Every violation shall trigger immediate liability; and each day that the violation(s) continues shall be deemed a separate instance of non-compliance.
Wastewater: Liquid or water-carried wastes and/or sewage from residential dwellings, commercial buildings, research facilities, industrial and manufacturing facilities, and institutions, whether treated or untreated.