Prohibited discharges can be general or specific. These prohibitions exists to ensure that the POTW has the ability to comply with its discarge requirements.
Sewer users are prohibited from introducing or causing to be introduced into the POTW any pollutant or wastewater which causes Pass Through or Interference. This general prohibition applies to all dischargers whether or not they are subject to categorical Pretreatment Standards or any other National, State, or local Pretreatment Standards or Requirements.
Sewer users are prohibited from introducing or causing to be introduced into the POTW the following pollutants, substances, or wastewater:
- Pollutants which create a fire or explosive hazard in the POTW, including, but not limited to, waste streams with a closed cup flashpoint of less than 140 degrees F(60 degrees C) using the test methods specified in 40 CFR 261.21
- Wastewater having a pH less than 5.0 or more than 11.5, or otherwise causing corrosive structural damage to the POTW or equipment
- Solid or viscous substances in amounts which will cause obstruction of the flow in the POTW resulting in Interference
- Pollutants, including oxygen demanding pollutants (BOD, etc.), released in a discharge at a flow rate and/or pollutant concentration which, either singly or by interaction with other pollutants, will cause Interference with the POTW
- Wastewater having a temperature greater than 104 degrees F (40 degrees C), and or which will inhibit biological activity in the treatment plant resulting in Interference
- Petroleum oil, non-biodegradable cutting oil, or products of mineral oil origin, in amounts that will cause Interference or Pass Through
- 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
- Trucked or hauled pollutants, except at specified discharge points and with CA approval
- Noxious or malodorous liquids, gases, solids, or other wastewater which, either singly or by interaction with other wastes, are sufficient to create a public nuisance or a hazard to life, or to prevent entry into the sewers for maintenance or repair
- Colored wastewater which cannot be removed by the treatment process, such as, but not limited to, dye wastes and vegetable tanning solutions, which consequently imparts color to the treatment plant’s effluent (a violation of the City’s MEPDES permit);
- Wastewater containing any radioactive wastes or isotopes
- Storm water, surface water, ground water, artesian well water, roof runoff, subsurface drainage, swimming pool drainage, condensate, de-ionized water, non-contact cooling water, and unpolluted wastewater, unless specifically authorized
- Sludges, screenings, or other residues from the pretreatment of industrial wastes or other packaged wastewater treatment plants;
- Medical wastes, except as specifically authorized in an individual wastewater discharge permit
- Wastewater causing, alone or in conjunction with other sources, the treatment plant’s effluent to fail toxicity test
- Detergents, surface active agents, or other substances that might cause excessive foaming in the POTW
- Fats, oils, or greases of animal or vegetable origin in concentrations greater than 200 milliliters per liter
- Wastewater causing two readings on an explosion hazard meter at the point of discharge into the POTW, or at any point in the POTW, of more than 10% (10 %) of the lower explosive limit (LEL) or any single reading over the LEL of the meter
See Chapter 71 §2- General Sewer Use Requirements for more information.