(1) Any liquids, solids or gases which by reason of 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 POTW or to the operation of the POTW. At no time shall two successive readings on an explosion hazard meter, at the point of discharge into the system (or at any point in the system) be more than five percent nor any single reading over 10 percent 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, sulfides, and any pollutant which creates a fire hazard or explosion hazard in the POTW, including but not limited to waste streams with a closed cup flashpoint of less than 140 degrees Fahrenheit or 60 degrees Celsius.

(2) Solid or viscous substances which 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 in any dimension, animal guts or tissue, paunch manure, bones, hair, hides or fleshings, entrails, whole bloods, feathers, ashes, cinders, sand, spent lime, stone or marble dust, metal, glass, straw, shavings, grass clippings, rags, spent grains, spent hops, wastepaper, wood, plastics, gasoline, tar, asphalt, residues, residues from refining or processing of fuel or lubricating oil, mud or glass grinding or polishing waste.

(3) Any wastewater having a pH of less than 5.5 or greater than 10.8, or wastewater having any other corrosive property capable of causing damage or hazard to structures, equipment and/or personnel of the POTW.

(4) Any wastewater containing 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, create an interference in the receiving waters of the POTW, or to exceed the limitation set forth in a categorical pretreatment standard. Such pollutants shall include but not be limited to any pollutant identified pursuant to Section 307(a) of the Act.

(5) Any pollutants which result in the presence of toxic gases, vapors or fumes within the POTW in a quantity that may cause acute worker health and safety problems.

(6) Any substance which may cause the POTW’s effluent or any other product of the POTW 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 POTW cause the POTW 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 Substance Control Act, or State criteria applicable to the sludge management method currently being used by the City.

(7) Any substance which will cause the POTW to violate its NPDES and/or State discharge system permit or the receiving water quality standards.

(8) Any wastewater with objectionable color not removed in the treatment process, such as but not limited to dye wastes and vegetable tanning solutions.

(9) Any wastewater having a temperature which will inhibit biological activity in the POTW treatment plant resulting in interference, but in no case wastewater with a temperature at the introduction into the POTW which exceeds 40 degrees Celsius (104 degrees Fahrenheit).

(10) Any pollutants, including oxygen-demanding pollutants (BOD, etc.) released at a flow rate and/or pollutant concentration which a user knows or has reason to know will cause interference to the POTW. In no case shall a slug load have a flow rate or contain concentration or quantities of pollutants that exceed for any time period longer than 15 minutes more than five times the average 24-hour concentrations, quantities or flow during normal operation.

(11) Any wastewater containing any radioactive waste or isotope of such half-life or concentration as may exceed limits established by the Utilities Director in compliance with applicable State or Federal regulations.

(12) Any wastewater which causes a hazard to human life or creates a nuisance.

(1) Advise the user of the impact of the contribution on the POTW; and

(2) Develop effluent limitations for such user to correct the interference with the POTW.