§ 58-131. Prohibited discharges.

(a)

No user shall contribute or cause to be contributed, directly or indirectly, any pollutant or wastewater which will cause interference or pass through. This general prohibition applies to all users of the municipal wastewater system, whether or not the user is subject to categorical pretreatment standards or any other national, state or local pretreatment standards or requirements. Furthermore, no user may contribute the following substances to the system:

(1)

Any liquids, solids or gases which, by reason of their nature or quantity, are or may be sufficient, either alone or by interaction with other substances, to cause fire or explosion or be injurious in any other way to the municipal wastewater system. Included in this subsection are waste streams with a closed cup flashpoint of less than 140 degrees Fahrenheit (60 degrees Celsius). At no time shall two successive readings on an explosion hazard meter at the point of discharge into the system or at any point in the system be more than five percent nor any single reading over ten percent of the lower explosive limits (LEL) of the meter.

(2)

Solid or viscous substances in amounts which will cause interference with the flow in a sewer but in no case solids greater than one-half inch (1.27 centimeters) in any dimension.

(3)

Any fats or greases, including but not limited to petroleum oil, nonbiodegradable cutting oil or products of mineral oil origin, in amounts that will cause interference or pass through.

(4)

Any wastewater having a pH less than 5.0 or more than 9.0, or otherwise causing corrosive structural damage to the system, city personnel or equipment.

(5)

Any wastewater containing pollutants in sufficient quantity (flow or concentration), either singly or by interaction with other pollutants, to pass through or interfere with the municipal wastewater system, any wastewater treatment or sludge process or constitute a hazard to humans or animals.

(6)

Any noxious or malodorous liquids, gases or solids or other solids or other wastewater which, either singly or by interaction with other wastes, are sufficient to create a public nuisance or hazard to life or are sufficient to prevent entry into the sewers for maintenance and repair.

(7)

Any substance which may cause the treatment plant effluent or any other residues, sludges or scums to be unsuitable for reclamation and reuse or to interfere with the reclamation process. No substance discharged to the system shall cause the city to be in noncompliance with sludge use or disposal regulations or permits issued under section 405 of the act, the Solid Waste Disposal Act, the Clean Air Act, the Toxic Substances Control Act or other state requirements applicable to the sludge use and disposal practices being used by the city.

(8)

Any wastewater which imparts color which cannot be removed by the treatment process, such as but not limited to dye wastes and vegetable tanning solutions, which consequently imparts color to the treatment plant effluent violating the city's NPDES permit. Color, in combination with turbidity, shall not cause the treatment plant effluent to reduce the depth of the compensation point for photosynthetic activity by more than ten percent from the seasonably established norm for aquatic life.

(9)

Any wastewater having a temperature greater than 150 degrees Fahrenheit (35 degrees Celsius) or which will inhibit biological activity in the treatment plant resulting in interference, but in no case wastewater which causes the temperature at the introduction into the treatment plant to exceed 104 degrees Fahrenheit (40 degrees Celsius).

(10)

Any wastewater containing any radioactive wastes or isotopes, except as specifically approved by the superintendent in compliance with applicable state or federal regulations.

(11)

Any pollutants which result in the presence of toxic gases, vapors or fumes within the system in a quantity that may cause worker health and safety problems.

(12)

Any trucked or hauled pollutants, except at discharge points designated by the city in accordance with section 58-143.

(13)

Stormwater, surface water, groundwater, artesian well water, roof runoff, subsurface drainage, swimming pool drainage, condensate, deionized water, cooling water and unpolluted industrial wastewater, unless specifically authorized by the superintendent.

(14)

Any industrial wastes containing floatable fats, waxes, grease or oils or which become floatable at the wastewater temperature at the introduction to the treatment plant during the winter season; but in no case industrial wastewater containing more than 100 mg/l of emulsified oil or grease.

(15)

Nonbiodegradable cutting oils, commonly called soluble oils, which form a persistent water emulsion, and nonbiodegradable complex carbon compounds.

(16)

Any sludges, screenings or other residues from the pretreatment of industrial wastes.

(17)

Any medical wastes, except as specifically authorized by the superintendent in a wastewater permit.

(18)

Any material containing ammonia, ammonia salts or other chelating agents which will produce metallic complexes that interfere with the municipal wastewater system.

(19)

Any material identified as hazardous waste according to 40 CFR 261, except as may be specifically authorized by the superintendent.

(20)

Any wastewater causing the treatment plant effluent to show a lethal concentration of 50 percent (l.c. ₅₀ ) as determined by a toxicity test of 96 hours or less, using a percentage of the discharge and aquatic test species chosen by the superintendent.

(21)

Recognizable portions of the human or animal anatomy.

(22)

Any wastes containing detergents, surface active agents or other substances which may cause excessive foaming in the municipal wastewater system.

(b)

Wastes prohibited by this section shall not be processed or stored in such a manner that these wastes could be discharged to the municipal wastewater system. All floor drains located in process or materials storage areas must discharge to the industrial user's pretreatment facility before connecting with the system.

(Ord. No. 91-4, § 2.1, 12-11-1991)