(A)   A user may not introduce into the POTW any pollutant(s) which cause pass through or interference. These general prohibitions and the specific prohibitions in division (B) below apply to each user introducing pollutants into the POTW whether or not the user is subject to national pretreatment standards or any national, state or local pretreatment requirements.
   (B)   A user shall have an affirmative defense in any action brought against it alleging a violation of the general prohibitions established in division (B)(1) below and the specific prohibitions in divisions (C)(3), (4), (5), (6) and (7) below where the user can demonstrate that:
      (1)   It did not know or have reason to know that its discharge, alone or in conjunction with a discharge or discharges from other sources would cause pass through or interference;
      (2)   A local limit designed to prevent pass through and/or interference, as the case may be, was developed in accordance with 40 CFR 403.5(c) for each pollutant in the user's discharge that caused pass through or interference, and the user was in compliance with each local limit directly prior to and during the pass through or interference; or
      (3)   If a local limit designed to prevent pass through and/or interference, as the case may be, has not been developed in accordance with 40 CFR 403.5(c) for the pollutants that caused the pass through or interference, the user's discharge directly prior to and during the pass through or interference did not change substantially in nature and constituents from the user's prior discharge activity when the POTW was regularly in compliance with the POTW's NPDES permit requirements and, in the case of interference, applicable requirements for sewage sludge use or disposal.
   (C)   In addition, the following pollutants shall not be introduced into the POTW:
      (1)   Pollutants which create a fire or explosion hazard in the POTW, including, but not limited to wastestreams with a closed cup flashpoint of less than 140°F. or 60°C. using the test methods specified in 40 CFR 261.21;
      (2)   Pollutants which will cause corrosive structural damage to the POTW, but in no case discharges with pH lower than 5.0, or greater than or equal to 12.5 standard units, unless the works is specifically designed to accommodate, the discharges;
      (3)   Solid or viscous pollutants in amounts which will cause obstruction to the flow in the POTW resulting in interference, such as, but not limited to grease, garbage with particles greater than ½-inch in any dimension, 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, spent grains, spent hops, waste paper, wood, plastics, gas, tar, asphalt, residues, residues from refining or processing of fuels or lubricating oil, mud or glass grinding or polishing wastes;
      (4)   Any pollutant, including oxygen- demanding pollutants (BOD and the like) released in a discharge at a flow rate and/or pollutant concentration which will cause interference with the POTW;
      (5)   Heat in amounts which will inhibit biological activity in the POTW resulting in interference, but in no case heat in the quantities that the temperature at the POTW treatment plant exceeds 40°C., (104°F.), unless the approval authority, upon request of the POTW, approves alternate temperature limits;
      (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;
      (8)   Any trucked or hauled pollutants, except at discharge points designated by the POTW;
      (9)   Any wastewater containing any radioactive wastes or isotopes, of a half life or concentration as may exceed limits established by the plant manager in compliance with applicable state or federal regulations;
      (10)   Any wastewater which causes a hazard to human life or creates a public nuisance;
      (11)   Any stormwater, surface water, groundwater, roof runoff, subsurface drainage or uncontaminated cooling water unless specific approval is obtained from the plant manager; (Stormwater and all other unpolluted drainage shall be discharged to the sewers as are specifically designated as storm sewers, or to a natural outlet approved by the plant manager and the state. Industrial cooling waters may be discharged on approval of the plant manager and the state to a storm sewer or natural outlet.)
      (12)   The use of enzymes, hot water, emulsifiers or other agents to cause oil and/or grease to pass through the user's grease trap or treatment unit designed to remove oil and/or grease; and
      (13)   No user shall ever increase the use of process water or, in any way, attempt to dilute a discharge as a partial or complete substitute for adequate treatment to achieve compliance with the limitations contained in the federal categorical pretreatment standards, or in any other pollutant-specific limitation developed by the city or state.
(Prior Code, § 17-413) (Ord. 1505, passed 7-6-93) Penalty, see § 10.99