No person shall discharge or cause to be discharged any of the following described waters or wastes to any public sewer:

    1. Any gasoline, benzene, naphtha, fuel oil or other flammable or explosive liquid, solid or gas;

    2. Any waters or wastes containing toxic or poisonous solids, liquids or gases in sufficient quantity to either singly or by interaction with other wastes, injure or interfere with any sewage treatment process, constitute a hazard to humans or animals, create a public nuisance or create a hazard in the receiving waters of the sewage treatment plant, including, but not limited to, cyanides in excess of two mg/1 as CN in the wastes as discharged into the public sewer;

    3. Any discharge prohibited by 40 CFR Section 403.5;

    4. Any discharge prohibited by 40 CFR Section 403.6;

    5. Any combination of discharges that cause a treatment plant to exceed its influent capacity as listed in Section 8 of the city of Sioux City's 1983 Pretreatment Program.  (Ord. 83/T-2039; S-39108, 1979).