§ 53.24 HAZARDOUS DISCHARGES.
   (A)   Flammable, toxic, corrosive, and obstructive substances; preliminary treatment.
      (1)   No person shall discharge or cause to be discharged any of the following described waters or wastes to any public sewers:
         (a)   Any gasoline, benzene, naphta, fuel oil, or other flammable or explosive liquid, solid, or gas;
         (b)   Any waters or wastes containing toxic or poisonous solids, liquids, or gases in sufficient quantity, either singly or by interaction with other wastes, to injure or interfere with any sewage treatment process, constitute a hazard to humans or animals, create a public nuisance, or create any hazard in the receiving waters of the sewage treatment plant, including but not limited to cyanides in excess of two mg/l as CN in the wastes as discharged to the public sewer;
         (c)   Any waters or wastes having a pH lower than 5.5, or having any other corrosive property capable of causing damage or hazard to structures, equipment, and personnel of the sewage works;
         (d)   Solid or viscous substances in quantities or of such size capable of causing obstruction to the flow in sewers, or other interference with the proper operation of the sewage works such as, but not limited to, ashes, cinders, sand, mud, straw, shavings, metal, glass, rags, feathers, tar, plastics, wood, unground garbage, whole blood, paunch manure, hair and fleshings, entrails, and paper dishes, cups, mild containers, and the like, either whole or ground by garbage grinders; or
         (e)   Any waters or wastes having a five-day BOD greater than 300 parts per million by weight, or containing more than 350 parts per million by weight of suspended solids, or having an average daily flow greater than 2% of the average sewage flow of the city shall be subject to the review of the Superintendent.
      (2)   Where necessary in the opinion of the Superintendent, the owner shall provide, at his or her expense, such preliminary treatment as may be necessary to reduce the biochemical oxygen demand to 300 parts per million by weight, or reduce the suspended solids to 350 parts per million by weight, or control the quantities and rates of discharge of such waters or wastes. Plans, specifications, and any other pertinent information relating to proposed preliminary treatment facilities shall be submitted for the approval of the Superintendent and no construction of such facilities shall be commenced until the approvals are obtained in writing.
   (B)   Specific prohibitions as determined by Superintendent. No person shall discharge or cause to be discharged the following described substances, materials, waters, or wastes if it appears likely in the opinion of the Superintendent that such wastes can harm either the sewers, sewage treatment process, or equipment, have an adverse effect on the receiving stream, or can otherwise endanger life, limb, public property, or constitute a nuisance. In forming his or her opinion as to the acceptability of these wastes, the Superintendent will give consideration to such factors as the quantities of subject wastes in relation to flows and velocities in the sewers, materials of construction of the sewers, nature of the sewage treatment process, capacity of the sewage treatment plant, degree of treatability of wastes in the sewage treatment plant, and other pertinent factors. The substances prohibited are:
      (1)   Any liquid or vapor having a temperature higher than 150°F (65°C);
      (2)   Any water or waste containing fats, wax, grease or oils, whether emulsified or not, in excess of 100 mg/l or containing substances which may solidify or become viscous at temperatures between 32° and 150°F;
      (3)   Any garbage that has not been properly shredded. The installation and operation of any garbage grinder equipped with a motor of three-fourths horsepower (0.76 hp metric) or greater shall be subject to the review and approval of the Superintendent;
      (4)   Any waters or wastes containing strong acid, iron, pickling wastes, or concentrated plating solutions whether neutralized or not;
      (5)   Any waters or wastes containing iron, chromium, copper, zinc, and similar objectionable or toxic substances; or wastes exerting an excessive chlorine requirement, to such degree that any such material received in the composite sewage at the sewage treatment works exceeds the limits established by the state for such materials;
      (6)   Any waters or wastes containing phenols or other taste- or odor-producing substances, in such concentrations exceeding limits which may be established by the state as necessary, after treatment of the composite sewage, to meet the requirements of state, federal, or other public agencies of jurisdiction for such discharge to the receiving waters;
      (7)   Any radioactive wastes or isotopes of such half-life or concentration as may exceed limits established by the state in compliance with applicable state or federal regulations;
      (8)   Any waters or wastes having a pH in excess of 11;
      (9)   Materials which exert or cause:
         (a)   Unusual concentrations of inert suspended solids (such as, but not limited to, Fullers earth, lime slurries, and lime residues) or of dissolved solids (such as, but not limited to, sodium chloride or sodium sulfate);
         (b)   Excessive discoloration (such as, but not limited to, dye wastes and vegetable tanning solutions);
         (c)   Unusual BOD, chemical oxygen demand, or chlorine requirements in such quantities as to constitute a significant load on the sewage treatment works; or
         (d)   Unusual volume of flow or concentration of wastes constituting “slugs” as defined herein.
      (10)   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.
   (C)   Rejection, pretreatment, control of discharge, or use fee surcharge.
      (1)   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 division (B) above, and which in the judgment of the Superintendent may have a deleterious effect upon the sewage works, processes, equipment, or receiving waters, or which otherwise create a hazard to life to constitute a public nuisance, the Superintendent may:
         (a)   Reject the wastes;
         (b)   Require pretreatment to an acceptable condition for discharge to the public sewers;
         (c)   Require control over the quantities and rates of discharge; and/or
         (d)   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 division (D) below.
      (2)   If the Superintendent permits the pretreatment or equalization of waste flows, the design and installation of the plants and equipment shall be subject to the review and approval of the NDEE and subject to the requirements of all applicable codes, ordinances, and laws.
   (D)   Special exceptions permitted; use fee surcharge. No statement contained in this chapter shall be construed as preventing any special agreement or arrangement between the city and any industrial concern whereby an industrial waste of unusual strength of character may be accepted by the city for treatment, subject to payment therefore by the industrial concern.
(Prior Code, § 53.24) Penalty, see § 53.99