The following general prohibitions shall apply to all users of the POTW unless the user is subject to a more restrictive National Categorical Pretreatment Standards, the Iowa Department of Natural Resources, or wastewater discharge permit limit. The following substances are prohibited from discharge to the POTW:
1. Pollutants creating a fire or explosion hazard in the POTW, including but not limited to waste streams with a closed cup flashpoint of less than 140 degrees Fahrenheit (60 degrees Celsius) using test methods referenced in 40 CFR 261.21. Waste streams shall not be ignitable at ambient temperatures. At no time shall two successive readings on a meter capable of reading L.E.L. (lower explosive limit) at the nearest accessible point to the POTW, at the point of discharge into the POTW or at any point in the POTW, be more than five percent nor any single reading greater than ten percent.
2. Any substance which will cause corrosive structural damage to the POTW, but in no case discharges with pH lower than 5.0 or greater than 12.0.
3. Solid or viscous pollutants which will cause obstruction to the flow in the POTW resulting in interference. Such pollutants include but are not limited to grease, garbage with particles greater than one-half inch any dimension, animal tissues, paunch manure, bones, hair, hides or fleshings, entrails, whole blood, feathers, ashes, cinders, sand, spent lime, stone or marble dust, metal, glass, straw, shavings, grass clippings, rags, wipes, spent grains, spent hops, wastepaper, wood, plastics, tar, asphalt residues from refining or processing of fuel or lubricating oil, mud or glass grinding or polishing waste, or tumbling and de-burring stones, and wastewater containing fat, wax, O&G, or other substances which may solidify or become viscous at temperatures between 32 and 150 degrees Fahrenheit (0 and 65 degrees Celsius).
4. Any pollutant, including oxygen demanding pollutants (BOD, etc.) released in a discharge at a flow rate or pollutant concentration which will cause interference or pass through at the WRF or which constitutes a slug load as defined in this chapter.
5. Heat in amounts which will inhibit biological activity in the POTW resulting in interference, but in no case wastewater or vapor having a temperature higher than 150 degrees Fahrenheit (65 degrees Celsius) at the point of introduction into the POTW, and in no case wastewater or vapor which alone or in concert with other discharges produces a temperature at the WRF greater than 104 degrees Fahrenheit (40 degrees Celsius).
6. Petroleum oil, non-biodegradable cutting oil, or products of mineral oil origin in amounts that will cause interference or pass through.
7. 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 or a public nuisance.
8. Any trucked or hauled pollutants, except at discharge points designated by the WRA.
9. Any radioactive material as defined in the Atomic Energy Act of 1954, as amended, and as defined in I.C. §136C.1, except materials which meet conditions of disposal by release into sanitary sewerage pursuant to 10 CFR 20.2003.
(Subsection 9 – Ord. 22-07 – Oct. 22 Supp.)
10. Any wastewater containing concentrations of 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, which exceed 3,000 mg/l nonvolatile or 3,000 mg/l total dissolved solids unless approved by the WRA Director.
11. Pollutants causing excessive discoloration, such as but not limited to dye waste and vegetable tanning solutions.
12. Hazardous waste pharmaceuticals for human or animal use as defined in 40 CFR 266.500.
(Subsection 12 – Ord. 22-07 – Oct. 22 Supp.)