921.15 SUBSTANCES LIMITED.
   The following described substances, materials, waters, or waste shall be limited in discharges to municipal systems to concentrations or quantities which will not harm either the sewers, wastewater treatment process or equipment, will not have an adverse effect on the receiving stream, or will not otherwise endanger lives, limb, public property, or constitute a nuisance. The Superintendent may set limitations lower than the limitations established in the regulations below if in his opinion such more severe limitations are necessary to meet the above objectives. Deliberate dilution with unpolluted water to meet the concentrations established in the regulations below shall not be acceptable. In forming his opinion as to the acceptability, the Superintendent will give consideration to such facts as the quantity of subject waste in relation to flows and velocities in the sewers, material of construction of the sewers, the wastewater treatment process employed, capacity of the wastewater treatment plant, degree of treatability of the waste in the wastewater treatment plant, and other pertinent factors. The limitations or restrictions on materials or characteristics of waste or wastewater discharged to the sanitary sewer which shall not be violated without approval of the Superintendent are as follows:
   (a)   Wastewater having a temperature higher than 150 degrees F;
   (b)   Wastewater containing more than 50 milligrams per liter of petroleum oil, nonbiodegradable cutting oils, product of mineral oil origin, or floatable oils, fat, wax, or grease, whether emulsified or not;
   (c)   Any garbage that has not been properly shredded. Garbage grinders may be connected to sanitary sewers from homes, hotels, institutions, restaurants, hospital, catering establishments or similar places where garbage originates from the preparation of food in kitchens for the purpose of consumption on the premises or when served by caterers.
   (d)   Any waters or wastes containing solids, liquids or gases in sufficient quantity either singly or by interaction with other wastes to injure or interfere with any wastewater treatment process, constitute a hazard to humans or animals, create a public nuisance, or create any hazard in the receiving waters of the Wastewater Treatment Plant, including, but not limited to, cyanides, hexavalent chromium, copper, zinc, cadmium, nickel and phenols in the waste as discharged to the public sewer. The following concentrations shall not be exceeded in industrial waters discharged to the public sewers: Ag(silver)-0.2 milligrams per liter(mg/l); Cd(Cadmium)-0.2 mg/l; CN(total cyanide)-0.5 mg/l; Cr + 6(hexavalent chromium)-0.25 mg/l; Cr(total Chromium)-4.2 mg/l; Cu(Copper) 1.0 mg/l; Fe(Iron); Hg(Mercury) 0.01 mg/l; Ni(Nickel) 2.0 mg/l; Pb(Lead)-0.5 mg/l; Phenols-0.2 mg/l; Zn(Zinc)-1.0 mg/l.
These maximum concentrations may be changed as necessary by the Superintendent or state regulatory agencies based on new information concerning inhibitory substances or to protect treatment plant processes. Industrial dischargers covered by Federal pre-treatment requirements shall meet those limitations specified under the effluent guidelines published under Section 304(b) and 307(b) of the Federal act or the above concentrations, whichever is more stringent. Major contributing industries discharging incompatible pollutants into the public sewers shall be regulated as provided in Section 921.16 .
   (e)   Any waters or wastes containing odor-producing substances exceeding limits which may be established by the Superintendent or any local or State regulatory agencies.
   (f)   Any radioactive wastes or isotopes of such half-life or concentration as may exceed limits in compliance with applicable State or Federal regulations.
   (g)   Quantities of flow, concentrations or both which constitute a “slug” as defined herein.
   (h)   Waters or wastes containing substances which are not amenable to treatment or reduction by the wastewater treatment process employed, or are amenable only to such degree that the wastewater treatment plant effluent cannot meet the requirements of other agencies having jurisdiction over discharge of the receiving waters.
   (i)   Any water or wastes which by interaction with other water or wastes in the public sewer system, release obnoxious gases, form suspended solids which interfere with the collection system, or create a condition deleterious to structures and treatment processes. (Ord. 386-1997. Passed 12-15-97.)