A. No user shall discharge or cause to be discharged, directly or indirectly, any of the following described substances into the wastewater disposal system or to any public sewer.
1. Any liquids, solids or gases which by reason by 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 wastewater disposal system or to the operation of the system. At no time, shall two (2) successive readings on an explosion hazard meter, at the point of discharge into the system or any point in the system, be more than five percent (5%) nor any single reading over ten percent (10%) of the lower explosive limit (LEL) of the meter. Prohibited materials include, but are not limited to, gasoline, kerosene, naphtha, benzene, toluene, xylene, ethers, alcohols, ketones, aldehydes, peroxides, chlorates, perchlorates, bromates, carbides, hydrides and sulfides.
2. Solid or viscous substances which will or may cause obstruction to the flow in a sewer or other interference with the operation of the wastewater treatment facilities such as, but not limited to, grease, garbage with particles greater than one-half inch (1/2") in any dimension, animal guts or tissues, paunch manure, bones, hair, hides or fleshings, entrails, whole blood, feathers, ashes, cinders, sand, spent lime, stone or marble dust, metal, glass, straw, shavings, grass clippings, leaves, rags, spent grains, spent hops, wastepaper, wood, plastic, gas, tar, asphalt residues, residues from refining or processing of fuel or lubricating oil, mud or glass grinding or polishing wastes.
3. Any wastewater having a pH lower than 5.0 or greater than 11.0 or having any other corrosive property capable of causing damage or hazard to structures, equipment and personnel of the wastewater disposal system.
4. Any wastewater containing toxic pollutants in sufficient quantity, either singly or by interaction with other pollutants, to injure or interfere with any wastewater treatment process, constitute a hazard to humans or animals, or create a toxic effect in the receiving waters of the wastewater disposal system. A toxic pollutant shall include, but not be limited to, any pollutant identified pursuant to section 307(a) of the act.
5. Any radioactive wastes or isotopes of such half-life or concentration as may exceed limits established by applicable state or federal regulations.
6. Any noxious or malodorous liquids, gases or solids, which either singly or by interaction with other wastes are capable of creating a public nuisance or hazard to life or are sufficient to prevent entry into the sewers for their maintenance and repair.
7. Any substance which may cause the wastewater disposal system's effluent or any other product of the wastewater treatment process such as residues, sludges or scums, to be unsuitable for reclamation and reuse or to interfere with the reclamation process. In no case, shall a substance discharged to the wastewater disposal system cause the system to be in noncompliance with sludge use or disposal criteria, guidelines or regulations developed under section 405 of the act; any criteria, guidelines or regulations affecting sludge use or disposal developed pursuant to the solid waste disposal act, the clean air act, the toxic substances control act or state standards applicable to the sludge management method being used.
8. Any substance which will cause the wastewater disposal system to violate its NPDES and/or state disposal system permit or the receiving water quality standards.
9. Any wastewater with objectionable color not removed in the treatment process, such as, but not limited to, dye wastes and vegetable tanning solutions.
10. Any wastewater which creates conditions at or near the wastewater disposal system which violates any statute or any rule, regulation or ordinance of any public agency or state or federal regulatory body.
11. Any wastewater having a temperature greater than one hundred fifty degrees Fahrenheit (150°F) (65.6°C) or causing, individually or in combination with other wastewater, the influent at the wastewater treatment plant to have a temperature exceeding one hundred four degrees Fahrenheit (104°F) (40°C), or having heat in amounts which will inhibit biological activity in the publicly owned treatment works resulting in interference.
12. Any slug load, which shall mean any pollutant, including oxygen demanding pollutants (BOD, etc.), released in a discharge of such volume or strength which, either singly or by interaction with other pollutants will cause interference in the wastewater disposal system.
13. Any unpolluted water including, but not limited to, non-contact cooling waters, storm water, surface waters, roof runoff, subsurface drainage or ground water.
14. Any wastewater containing fats, wax, grease or oils, whether emulsified or not, in excess of one hundred fifty milligrams per liter (150 mg/l) or containing substances which may solidify or become viscous at temperatures between thirty two degrees Fahrenheit (32°F) and one hundred fifty degrees Fahrenheit (150°F) (0°C) and (65.6°C); and any wastewater containing oil and grease concentrations of mineral origin of greater than one hundred milligrams per liter (100 mg/l), whether emulsified or not.
15. Wastewater containing inert suspended solids (such as, but not limited to, fuller's earth, lime slurries and lime residues) or of dissolved solids (such as, but not limited to, sodium chloride and sodium sulfate) in such quantities that they would cause interference with wastewater systems.
16. Any garbage that has not been properly shredded. The installation and operation of any garbage grinder equipped with a motor of three-fourths (3/4) horsepower (0.76 hp metric) or greater shall be subject to review and approval of authorized city personnel.
17. Waters or wastes containing substances which are not amenable to treatment or reduction by the sewage treatment processes employed, or are amenable to treatment only to such degree that the sewage treatment plant effluent cannot meet the requirements of other agencies having jurisdiction over discharge to the receiving waters.
18. Pollutants which create a fire or explosive hazard in the POTW, including, but not limited to, waste streams with a closed-cup flashpoint of less than 140 degrees F (60 degrees C) using the test methods specified in 40 CFR 261.21.
19. Petroleum oil, nonbiodegradable cutting oil, or products of mineral oil origin, in amounts that will cause interference or pass through.
In addition to these prohibitions, no user shall discharge to any public sewer any discharge which causes pass through or interference, with the wastewater disposal system. Pollutants in the effluent from an industrial user shall not be considered to cause pass through or interference where the industrial user is in compliance with specific prohibitions or standards developed by federal, state or local governments. Where the industrial user is in compliance with such specific prohibitions or standards, and pollutants in the effluent from the industrial user's facility nevertheless are determined to have caused or significantly contributed to a violation of any requirement of the city's NPDES or state disposal system permit, and are likely to cause such a violation in the future, the city must take appropriate action to develop and enforce specific effluent limits for that industrial user to ensure renewed and continued compliance with the city's NPDES or state disposal system permit.
B. If any waters or wastes are discharged, or are proposed to be discharged to the public sewers, which waters contain the substances or possess the characteristics enumerated in subsection A of this section, and which may have a deleterious effect upon the sewage works, processes, equipment or receiving waters, or which otherwise create a hazard to life or constitute a public nuisance, the city may:
1. Reject the wastes,
2. Require pretreatment to an acceptable condition for discharge to the public sewers,
3. Require control over the quantities and rates of discharge, and/or
4. Require payment to cover the added cost of handling and treating the wastes not covered by existing taxes or sewer charges under the provisions of section 7-2-5 of this chapter.
If the city permits or requires the pretreatment or equalization of waste flows, the design and installation of the plants and equipment shall be subject to review, approval of the city and to the requirements of all applicable codes, ordinances, laws and federal and state regulations.
C. All oils, greases, flammable wastes, sand or other harmful ingredients shall be removed from the interceptor and placed in containers and disposed of in such a manner that no part thereof shall drain into the sanitary sewer system.
Authorized city personnel shall make the necessary inspection of the interceptors described in this section and take all required steps of enforcement. Any person who is found in violation of this chapter shall be subject to the penalties of section 7-2-10 this chapter.
D. Where preliminary treatment or flow-equalizing facilities are provided for any waters or wastes, they shall be maintained continuously in satisfactory and effective operation by the owners at their expense.
E. New discharges of non-contact cooling water to the POTW are prohibited unless there is no cost-effective alternative. Existing discharges of non-contact cooling water to the POTW shall be eliminated where elimination is cost effective, or where infiltration/inflow analysis and sewer system evaluation indicate the need for such removal.
F. Wastes trucked or hauled to a POTW shall be discharged only at a point designated by the POTW authority. (1987 Code; amd. Ord. 2000-12, 9-5-2000; Ord. 2022-12, 5-23-2022)