(A) All premises connected to the POTW shall meet the following requirements.
(1) Minimum size of the building drain/sewer, including required cleanouts, shall be four inches or greater in diameter.
(2) A grease interceptor, with a maintenance cleaning schedule appropriate for its intended use, shall be required to receive the drainage from fixtures and equipment having grease-laden waste, located in food preparation areas such as in restaurants, commercial kitchens, bars, clubs or similar facilities. The grease interceptor shall not be less than a three compartment, 1,000 gallon system, or equivalent, unless the City Manager approves an alternative system. Food waste grinders shall not discharge to the building drainage system through the grease interceptor, unless the interceptor is appropriately sized to handle the solids loading and approved by the Plumbing Code. Grease interceptors shall be cleaned and maintained in accordance with BMP. At no time shall the level of grease and sludge in any compartment of the trap be greater than 25% of the tank liquid level. Proof of maintenance and cleaning shall be available for review upon request.
(3) Sand traps and similar interceptors for removal of heavy solids by commercial users, as determined by the City Manager, shall be designed and installed, according to the city sand trap for garages design specifications. They shall be located as to be readily accessible for cleaning and shall have a water seal of not less than six inches. Sand traps and similar interceptors shall be cleaned and maintained in accordance with BMP. Proof of maintenance and cleaning shall be available for review upon request.
(4) Oil/water separators are required at repair garages, gasoline stations with grease racks, grease pits or work racks and at factories, or other facilities, where oily and flammable liquid wastes are produced. Separators shall be installed into which all oil-bearing, grease-bearing or flammable wastes shall be discharged before emptying in the building drainage system or other point of disposal. Oil separators shall have a depth of not less than two feet below the invert of the discharge drain. The outlet opening of the separator shall not have less than an 18-inch water seal. An alternative design may be approved by the Plumbing Inspector, as provided for by the Plumbing Code. Oil/water separators shall be cleaned and maintained in accordance with BMP. Proof of maintenance and cleaning shall be available for review upon request.
(B) (1) No discharger shall introduce into the POTW any pollutant(s) which cause pass through or interference. The following general and specific prohibitions of this section apply to each discharger introducing pollutants into the POTW whether or not the discharger is subject to any national, state or local pretreatment standards or requirements.
(2) Pollutants, substances or wastewater prohibited by this section shall not be processed or stored in such a manner that they could be discharged to the POTW:
(a) Pollutants which create a fire or explosion hazard in the POTW, including, but not limited to, waste streams with a closed cup flashpoint of less than 140°F or 60°C using the test methods specified in 40 C.F.R. § 261.21;
(b) Solid or viscous pollutants in amounts that will cause obstruction to the flow in the POTW or results in interference;
(c) Pollutants which cause corrosive structural damage to the POTW, but in no case discharges with a pH lower than 5.0 or a pH greater than 10.5. These pH limits will be evaluated annually as part of the rate study and the limits set forth in this section will be revised as deemed necessary;
(d) Any wastewater containing toxic pollutants in sufficient quantity, either singly or by interaction, to injure or interfere with any wastewater treatment process, constitute a hazard to humans or animals or exceed the limitations set forth in a categorical pretreatment standard;
(e) Any noxious or malodorous liquids, gases or solids which either singly, or by interaction, are capable of creating a public nuisance or hazard to life or are sufficient to prevent entry into the sewers for maintenance and repair;
(f) Any substance which, alone or in conjunction with a discharge or discharges from other sources, may cause a violation of the POTW’s NPDES permit or any applicable state or federal water quality standards or interferes with any treatment process, or causes treatment residues, sludge’s or scum’s, to be unsuitable for reclamation or 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 § 405 of the Clean Water Act, being 33 U.S.C. § 1345, any criteria, guidelines or regulations affecting sludge use or disposal developed pursuant to the Solid Waste Disposal Act being 42 U.S.C. §§ 6901 et seq., the Clean Air Act being 42 U.S.C. §§ 7401 et seq., the Toxic Substances Control Act being 15 U.S.C. §§ 2601 et seq. or state standards applicable to the sludge management method being used;
(g) Any substance with objectionable color not removed in the treatment process, such as, but not limited to, dye wastes and vegetable tanning solutions;
(h) Heat in amounts that will inhibit biological activity in the POTW resulting in interference, but, in no case heat in such quantities that the temperature at the headworks of the POTW exceeds 40°C (104°F) unless the MDEQ, upon the request of the POTW, approves the alternative temperature limits;
(i) 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;
(j) Any unpolluted water including, but not limited to, noncontact cooling water, unless a discharge authorization is approved by the City Manager;
(k) Any wastewater containing any radioactive wastes or isotopes of such half-life or concentration except as set forth in 10 C.F.R. part 20. Introduction of radioactive wastes that interfere with the operation of the POTW including, but not limited to, the use and disposal of sludge, the recycling of any and all waste products, or if the discharge causes the POTW to violate any local, state or federal laws;
(l) 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;
(m) Any discharge of petroleum oil, non-biodegradable cutting oil, animal fat, vegetable fat, oil, grease, products of mineral oil or any combination thereof at a concentration of greater than 100 milligrams per liter, unless it can be demonstrated that matrix interference is responsible for levels greater than this amount, but, in no case in amounts that will cause an obstruction, interference or pass through in the POTW;
(n) Any substances not identified in division (m) above, that will become solid or viscous after entering the POTW;
(o) Any effluent having an average daily flow greater than 2% of the POTW’s average daily flow. The City Manager, upon review, may approve greater discharges subject to conditions as authorized by this chapter or special conditions he or she deems necessary in order to preserve and protect public health, safety and welfare, subject to conformance with the applicable state and federal law;
(p) Any trucked or hauled pollutants, except at discharge points designated by the City Manager;
(q) Any detectable level of mercury using EPA method 245.1 or 245.2 with a detection limit not to exceed 0.2 u.g/1 unless the user can demonstrate that matrix interference prevents the attainment of this level. Mercury sampling procedures, preservation and handling, and analytical protocol for compliance monitoring shall be in accordance with U.S. EPA method 245.1 or 245.2. In the event that mercury is detected, the user shall develop and implement a mercury elimination plan including elements deemed necessary by the City Manager to progress toward the goal of no detectable discharge of mercury. For users whose operation and discharge characteristics are substantially similar, a group mercury elimination plan may be acceptable. Dental facilities shall comply with Public Act 503 of 2008, being M.C.L.A. § 333.16631, and all best management practices promulgated by the state’s Department of Community Health in conjunction with the state’s Department of Environmental Quality (MDEQ);
(r) There shall be no discharge to the POTW of groundwater that has been contaminated with gasoline and related petroleum products that would qualify for a state general discharge permit for gasoline and related petroleum products in accordance with R 2191 promulgated pursuant to Act 451 of the state’s Public Acts of 1994, as amended, Part 31, except where no other discharge option exists. If discharge to the POTW is desired under these conditions, the discharger must submit a wastewater discharge permit application as specified in § 2.50 which may be approved by the City Manager. Upon approval, a permit will be issued with appropriate conditions as set forth in § 2.54. The total BTEX concentration shall not exceed 20 micrograms per liter and the MTBE concentration shall not exceed 20 micrograms per liter;
(s) Disposal of septage waste into the POTW is prohibited, except as in accordance with the septage waste receiving plan, the City Manager may authorize disposal of portable containers of domestic waste, including waste from recreational vehicles. Septage wastes are to be discharged only at designated locations in accordance with the septage waste receiving plan;
(t) Sludge from an industrial or commercial pretreatment system shall not be placed into the POTW. Such sludge shall be disposed of by a licensed hauler in a site approved by the MDEQ;
(u) Any substance that causes excessive foaming in the POTW;
(v) Medical Wastes, except as specifically authorized according to Part 138, Medical Waste Regulatory Act of the state’s Public Health Code, Public Act 368 of 1978, being M.C.L.A. §§ 333.1101 et seq.;
(w) Any detectable level of PCB using EPA method 608 with a detection limit not to exceed 0.1ug/1 unless the user can demonstrate that matrix interference prevents the attainment of this level. PCB sampling procedures, preservation and handling, and analytical protocol for compliance monitoring shall be in accordance with U.S. EPA method 608; and/or
(x) Bacteriological, chemical or enzymatic products shall not be added to facility discharge or be used to maintain or clean grease interceptors or grease traps, unless approved by the City Manager.
(C) Bypass is prohibited, except in cases where the bypass was unavoidable to prevent a loss of life, personal injury or severe property damage, and where there are no feasible alternatives to the bypass, such as the use of auxiliary treatment facilities, retention of untreated wastes or maintenance during normal periods of equipment downtime. This condition is not satisfied if adequate backup equipment should have been installed in the exercise of reasonable engineering judgment to prevent a bypass that occurred during normal periods of equipment downtime or preventive maintenance. In cases where a bypass may occur, it would be subject to the following conditions.
(1) Anticipated bypass. If an industrial user knows in advance of the need for a bypass, the user shall submit prior notice to the POTW, if possible, at least ten days before the date of the bypass. Upon notification, the City Manager shall make a determination whether to allow the discharge.
(2) Unanticipated bypass. An industrial user shall immediately notify the City Manager of the occurrence of any unanticipated bypass. The City Manager shall make a determination whether to allow the discharge to continue. A written submission shall also be provided within five days of becoming aware of the bypass. The written submission shall contain a description of the bypass and its cause, the dates and, if the bypass has not been corrected, the anticipated time it is expected to continue, and steps taken or planned to reduce, eliminate and prevent recurrence of the bypass.
(D) Any discharger shall have an affirmative defense in any action brought against it alleging a violation of the general and specific prohibitions established in divisions (B)(2)(b), (B)(2)(h), (B)(2)(i) and (B)(2)(m), where the discharger 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; and
(2) Either:
(a) A local limit designed to prevent pass through or interference was developed for each pollutant in the user’s discharge that caused pass through or interference and the user was in compliance with each such local limit immediately before and during the pass through or interference; or
(b) A local limit was not applicable and immediately before and during the pass through or interference the user’s discharge did not substantially change in volume or constituents from the user’s previous discharges when the POTW was regularly in compliance with its NPDES permit and, in the case of interference, all applicable requirements for sludge use or disposal.
(Ord. effective 11-15-2013)