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 Director of Public Works 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 opinion as to the acceptability of these wastes, the Director of Public Works 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 maximum limits established by regulatory agencies. The substances prohibited are:
(A) Any liquid or vapor having a temperature higher than 150°F (65°C);
(B) Any waters or wastes containing toxic or poisonous materials 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°F and 150°F (0°C and 65°C);
(C) Any garbage that has not been properly shredded. The installation and operation of any garbage grinder equipped with a motor of 3/4 horsepower (0.76 hp metric) or greater shall be subject to the review and approval of the city;
(D) Any waters or wastes containing strong acid, iron pickling wastes or concentrated plating solution, whether neutralized or no;.
(E) Any waters or wastes containing iron, chromium, copper, zinc or 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 Director of Public Works for such materials;
(F) Any waters or wastes containing phenols or other waste odor-producing substances in such concentration as to exceed limits which may be established by the Director of Public Works as necessary after treatment of the composite sewage to meet the requirements of the state, federal or other public agencies of jurisdiction for such discharge to the receiving waters;
(G) Any radioactive wastes or isotopes of such half-life or concentration as may exceed limits established by the Director of Public Works in compliance with applicable state or federal regulations;
(H) Any mercury or any of its compounds in excess of 0.0005 mg/l as Hg at any time except as permitted by the city in compliance with applicable state and federal regulations;
(I) Materials which exert or cause:
(1) Unusual concentrations or 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;
(2) Excessive discoloration, such as, but not limited to dye wastes and vegetable tanning solutions;
(3) Unusual BOD, chemical oxygen demand or chlorine requirements in such quantities as to constitute a significant load on the sewage treatment works; or
(4) Unusual volume of flow or concentrations of wastes constituting slugs, as defined herein;
(J) Waters or wastes containing substances which are not amenable to treatment or reduction by the sewage treatment processes employed, or are amendable to treatment only to such degree that the sewage treatment plant effluent cannot meet the requirements of agencies having jurisdiction over discharge to the receiving waters.