§ 31.060 PROHIBITED AND RESTRICTED DISCHARGES
   (A)   General prohibitions.
      (1)   A user may not introduce into a POTW any pollutant(s) which cause pass through or interference. These general prohibitions and the specific prohibitions in paragraph (B) of this section apply to each user introducing pollutants into a POTW whether or not the user is subject to other national pretreatment standards or any national state, or local pretreatment requirements.
      (2)   Any wastewater containing toxic 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 a toxic effect in the receiving waters of the POTW, or to exceed the limitation set forth in a categorical pretreatment standard. A toxic pollutant shall include, but not be limited to, any pollutant identified pursuant to Section 307(a) of the Act.
   (B)   Specific prohibitions.
      (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 140o F. or 60o C. using the test methods specified in 40 CFR 261.21.
   At no time shall two (2) 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 (5%) nor any single reading over ten percent (10%) 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, and any other substances which the city, state or EPA has notified the user is a fire hazard or a hazard to the system.
      (2)   Any waters or wastes having a pH lower than 6.0 or higher than 10.0 or having any other corrosive property capable of causing damage or hazard to structures, equipment, and personnel of the POTW.
      (3)   Solid or viscous pollutants in amounts which will cause obstruction to the flow in the POTW resulting in interference.
      (4)   Any pollutant, including oxygen demanding pollutants (BOD, etc.) 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 such quantities that the temperature at the POTW treatment plant exceeds 40o C. (104o 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)   Except where expressly authorized to do so by an applicable pretreatment standard or requirement, no industrial user shall ever increase the use of process water, or in any other way attempt to dilute a discharge as a partial or complete substitute for adequate treatment to achieve compliance with a pretreatment standard or requirement. The Commission may impose mass limitations on industrial users which are using dilution to meet applicable pretreatment standards or requirements, or in other cases where the imposition of mass limitations is appropriate.
      (10)   If an existing industrial user adds or changes a process or operation which may be included in a pretreatment standard subcategory, the existing industrial user must request this certification prior to commencing discharge from the added or changed process or operation. A new source must request this certification prior to commencing discharge.
      (11)   Wastewater from industrial plants or commercial businesses containing floatable oils, fat, or grease, whether emulsified or not, in excess of (100 mg/l) or containing substances which may solidify or become viscous at temperatures 32-150o F. (0-65o C.);
      (12)   Any garbage that has not been properly shredded. Garbage grinders may be connected to sanitary sewers from homes, motels, institutions, restaurants, hospitals, catering establishments, or similar places where garbage originates from the preparation of food in kitchens for the purpose of consumption on the premises or when served by caterers. The installation and operation of any garbage grinder equipped with a 3/4 HP motor or greater shall be subject to review and approval.
      (13)   Any waters or wastes containing odor-producing substances exceeding limits which may be established by the Commission.
      (14)   Any radioactive wastes or isotopes of such half-life or concentration as may exceed limits established by the Commission in compliance with applicable state or federal regulations.
      (15)   Any water or wastes which, by interaction with other water or wastes in the public sewer system, release obnoxious gases, form suspended solids which interfere with the collection system, or create a condition deleterious to structures and treatment processes.
      (16)   Any waters or wastes containing cadmium, chromium, copper, cyanide, iron, lead, nickel, zinc, PCB, or similar objectionable or toxic substances to such a level that prevent the use of acceptable sludge disposal methods, or pass through the treatment process unremoved and at such concentration that causes a violation of effluent limitations or water quality standards which are or may be established by state and federal agencies having jurisdiction.
      (17)   Waters or wastes containing substances which are not amendable to treatment or reduction by the wastewater treatment process employed, or are amendable to treatment only to such degree that the wastewater treatment plant effluent cannot meet the requirements of other agencies having jurisdiction over discharge to the receiving waters.
      (18)   Any waste or wastewater classified as a hazardous waste by the Resource Conservation and Recovery Act (RCRA) without at least, a sixty (60) day prior notification of such discharge to the Superintendent of the POTW. This notification must include the name of the waste, EPA hazardous waste number, type of discharge, volume/mass of discharge and time of occurrence. The Manager may deny or condition this discharge at any time.
   (C)   Restricted discharges.
   The following described substances, materials, waters or waste shall be limited in discharges to municipal systems to concentrations or quantities which will not harm either the sewers, wastewater treatment process, or equipment, will not have an adverse effect on the receiving stream, or will not otherwise endanger lives, limb, public property, or constitute a nuisance. The Water and Sewer Commission may set additional limitations or alter the limitations established in the regulations below. In forming its opinion as to the acceptability, the Commission shall give consideration to such factors as the quantity of subject waste in relation to flows and velocities in the sewers, the wastewater treatment process employed, capacity of the wastewater treatment plant, and other pertinent factors, such as phosphorous removal to meet discharge limitations. The limitations or restrictions on materials or characteristics of waste or wastewaters discharged to the sanitary sewer shall not be violated without written approval of the Commission.
      (1)   Any water or waste which has characteristics based on a 24-hour composite sample, or a shorter period composite sample if more representative which exceed the following normal maximum domestic wastewater parameter concentrations:
      Parameter   Maximum Allowable Concentration Without Surcharge
      BOD                  250 mg/l
      TSS                  250 mg/l
      NH3-N               25 mg/l
      (2)   The following limitations are established for characteristics of any wastewaters to be discharged into the municipal sewer system:
      Parameter                   Limit (mg/l)
      Arsenic                  0.30
      Calcium, total               0.024
      Chlorides, total               6,000
      Chromium, hexavalent            0.29
      Chromium, total               2.25
      Copper, total                  0.35
      Cyanide, total               0.06
      Iron, total                  25
      Lead, total                  0.15
      Mercury, total               0.0005
      Nickel, total                  0.35
      pH                     6.0-10
      Phenols                  15
      Selenium                  0.03
      Silver                     0.20
      Sulfate, total                  1,500
      Zinc                     1.50
      (3)   Where an effluent from an industrial process is mixed prior to treatment with wastewaters other than those generated by the regulated process, fixed alternative discharge limits may be derived for the discharge permit by the Manager. These alternative limits may be calculated using the Combined Wastestream Formula and/or Flow-weighted Average Formula set out in 40 CFR 403.6(a). Where the effluent limits in a categorical pretreatment standard are expressed only in terms of mass of pollutants per unit of production (production-based standard), the Manager may convert the limits to equivalent limitations expressed either in mass of pollutant that may be discharged per day or of effluent concentrations for purposes of calculating effluent permit limitations applicable to the permittee. The permittee shall be subject to all permit limits calculated in this manner under 40 CFR 403.6(c) and must fully comply with these alternative limits. All categorical industrial users subject to production-based standards must report production rates annually so that alternative permit limits can be calculated if necessary. The categorical industrial user must notify the Manager thirty (30) days in advance of any change in production levels that might affect the flow or other data used to calculate the effluent limits in the discharge permit.
(Ord. - -, passed 6-7-84; Am. Ord. 91-07-18, passed 7-18-91; Am. Ord. 93-08-19, passed 8-19-93; Am. Ord. 97-11-20, passed - - ; Am. Ord. 98-12-03, passed 12-3-98; Am. Ord. 2001-02-21(B), passed 2-21- 02; Am. Ord. 2007-03-15, passed 3-15-07; Am. Ord. 2015-10-08(A), passed 10-8-15; Am. Ord. 2019-09-019, passed 9-19-19)