(A) No person(s) shall discharge or cause to be discharged any unpolluted water such as stormwater, ground water, roof runoff, surface drainage, or non-contact cooling water to any sanitary sewer.
(B) Stormwater and all other unpolluted drainage shall be discharged to such sewers as are specifically designed as storm sewers or to a natural outlet approved by the city and other regulatory agencies. Industrial cooling water or unpolluted process waters may be discharged to a storm sewer or natural outlet on approval of the city and upon approval and the issuance of a discharge permit by the MPCA.
(C) No person(s) shall discharge or cause to be discharged any of the following described waters or wastes to any public sewers:
(1) Any liquids, solids, or gases which by reason of their nature or quantity are, or may be, sufficient either alone or by interaction with other substances to cause fire or explosion or be injurious in any other way to the wastewater disposal system or to the operation of the system. 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 sulfides;
(2) Solid or viscous substances which will or may cause obstruction to the flow in a sewer or other interference with the operation of the wastewater treatment facilities, such as, but not limited to, grease, garbage with particles greater than one-half inch in any dimension, animal guts or 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, spent grains, spent hops, waste paper, wood, plastic, asphalt residues, residues from refining or processing of fuel or lubricating oil, mud or glass grinding or polishing wastes;
(3) Any wastewater having a pH of less than 6.0 or greater than 10.0 or having any other corrosive property capable of causing damage or hazard to structures, equipment, or personnel of the wastewater disposal system;
(4) Any wastewater containing toxic pollutants in sufficient quantity, either singly or by interaction with other pollutants, to inhibit or disrupt any wastewater treatment process, constitute a hazard to humans or animals, or create a toxic effect in the receiving waters of the wastewater disposal system. A toxic pollutant shall include, but not be limited to, any pollutant identified pursuant to Section 307(a) of the Act.
(D) The following described substances, materials, water, or wastes shall be limited in discharges to municipal systems to concentrations or quantities which will not harm either sewers, the wastewater treatment works, treatment process or equipment, will not have an adverse effect on the receiving stream and/or soil, vegetation and ground water, or will not otherwise endanger lives, limb, public property, or constitute a nuisance. The Utilities Superintendent or his or her representative may set limitations lower than limitations established in the regulations below if, in his or her opinion, such more stringent limitations are necessary to meet the above objectives. In forming his or her opinion as to the acceptability of wastes, the Utilities Superintendent or his or her representative will give consideration to such factors as the quantity of subject waste in relation to flows and velocities in the sewers, materials of construction of the sewers, nature of the sewage treatment process, the city’s NPDES and/or SDS Permit, capacity of the sewage treatment plant, degree of treatability of the wastes in the sewage treatment plant, and other pertinent factors. The following limitations or restrictions on materials or characteristics of waste or wastewaters discharged to the sanitary sewer shall not be violated without the approval of the Utilities Superintendent or his or her designee:
(1) Any wastewater having a temperature greater than 150 degrees Fahrenheit (65.6 degrees Centigrade) or causing, individually or in combination with other wastewater, the influent at the wastewater treatment plant to have a temperature exceeding 104 degrees Fahrenheit (40 degrees Centigrade), or having heat in amounts which will inhibit biological activity in the wastewater treatment works resulting in interference therein;
(2) Any wastewater containing fats, wax, grease, or oils, whether emulsified or not, in excess of 50 mg/l or containing substances which may solidify or become viscus at temperatures between 32 degrees Fahrenheit and 150 degrees Fahrenheit (0 degrees Centigrade and 65.6 degrees Centigrade); and any wastewater containing oil and grease concentrations of mineral origin of greater than 50 mg/l, whether emulsified or not;
(3) Any quantities of flow, concentrations, or both which constitute a slug as defined herein;
(4) Any garbage not properly shredded, as defined herein. Garbage grinders may be connected to sanitary sewers from homes, hotels, institutions, restaurants, hospitals, catering establishments, or similar places where garbage originates from the preparation of food on the premises or when served by caterers;
(5) Any noxious or malodorous liquids, gases, or solids which either singly or by interaction with other wastes are capable of creating a public nuisance or hazard to life, or are sufficient to prevent entry into the sewers for their maintenance and repair;
(6) Any wastewater with objectionable color not removed in the treatment process, such as, but not limited to, dye wastes and vegetable tanning solutions;
(7) Non-contact cooling water or unpolluted storm, drainage, or ground water;
(8) Wastewater containing inert suspended solids (such as, but not limited to, Fullers earth, lime slurries, and lime residues) or of dissolved solids (such as, but not limited to, sodium chloride and sodium sulfate) in such quantities that would cause disruption within the wastewater disposal system;
(9) Radioactive wastes or isotopes of such a half-life or concentration that they are in noncompliance with standards issued by the appropriate authority having control over their use and which will or are likely to cause damage or hazards to the city’s wastewater treatment system or personnel;
(10) Wastewater containing the following substances in excess of the limits shown herein:
Toxic Pollutant | Discharge Limitation |
Toxic Pollutant | Discharge Limitation |
Cadmium (Cd) | 1.03 mg/l |
Chromium total (Cr) | 5.23 mg/l |
Copper (Cu) | 2.86 mg/l |
Cyanide (Cn) | 1.09 mg/l |
Lead (Pb) | 1.05 mg/l |
Mercury (Hg) | 0.01 mg/l |
Nickel (Ni) | 3.65 mg/l |
Silver (Ag) | 2.14 mg/l |
Zinc (Zn) | 8.10 mg/l |
(11) Any wastewater which creates conditions at or near the wastewater disposal system which violates any statute, rule, regulations, or ordinance of any regulatory agency, or state or federal regulatory body;
(12) Any waters or wastes containing BOD5 in excess of 260 mg/l or total suspended solids in excess of 280 mg/l, except as may be permitted by specific written agreement subject to the provisions of this section.
(E) If any waters or wastes are discharged or are proposed to be discharged to the public sewers which contain substances or possess the characteristics enumerated in division (D) of this section, and/or which in the judgment of the Utilities Superintendent or his or her representative may have a deleterious effect upon the wastewater treatment facilities, processes, or equipment; receiving waters and/or soil, vegetation, and ground water; or which otherwise create a hazard to life or constitute a public nuisance, the city may;
(1) Reject the wastes;
(2) Require pretreatment to an acceptable condition for discharge to the public sewers, pursuant to Section 307(b) of the Act and all addendums thereof;
(3) Require control over the quantities and rates of discharge; and/or
(4) Require payment to defray the added costs of handling, treating, and disposing of wastes not defined, treating, and disposing of wastes not defrayed by existing taxes or sewer service charges. If the city permits the pretreatment or equalization of waste flows, the design, installation, and maintenance of the facilities and equipment shall be made at the owners’ expense and shall be subject to the review and approval of the city pursuant to the requirements of the MPCA.
(F) No user shall increase the use of process water or, in any manner, attempt to dilute a discharge as a partial or complete substitute for adequate treatment to achieve compliance with the limitations contained in divisions (C) and (D) of this section, or contained in the National Categorical Pretreatment Standards or any state requirements.
(G) Where pretreatment or flow-equalizing facilities are provided or required for any waters or wastes, they shall be maintained continuously in satisfactory and effective operation at the expense of the owner(s).
(H) Grease, oil, and sand interceptors shall be provided when, in the opinion of the Utilities Superintendent or his or her representative, they are necessary for the proper handling of liquid wastes containing floatable grease in excessive amounts, as specified in subsection (D)(2) any flammable wastes as specified in subsection (C)(1), sand or other harmful ingredients; except that such interceptors shall not be required for private living quarters or dwelling units. All interceptors shall be of the type to be readily and easily accessible for cleaning and inspection. In the maintaining of these interceptors, the owner(s) shall be responsible for the proper removal and disposal of the captured materials by appropriate means, and shall maintain a record of dates and means of disposal which are subject to review by the Utilities Superintendent or his or her representative. Any removal and hauling of the collected materials not performed by the owner’s personnel must be performed by a currently licensed waste disposal firm.
(I) Where required by the city, the owner of any property serviced by a building sewer carrying industrial wastes shall install a suitable structure, or control manhole, with such necessary meters and other appurtenances in the building sewer to facilitate observation, sampling, and measurement of wastes. Such structure shall be accessible and safely located and shall be constructed in accordance with plans approved by the city. The structure shall be installed by the owner at his or her expense and shall be maintained by the owner to be safe and accessible at all times.
(J) The owner of any property serviced by a building sewer carrying industrial wastes may, at the discretion of the city, be required to provide laboratory measurements, tests, or analyses of waters or wastes to illustrate compliance with this section and any special condition for discharge established by the city or regulatory agencies having jurisdiction over the discharge. The number, type, and frequency of sampling and laboratory analyses to be performed by the owner shall be as stipulated by the city. The industry must supply a complete analysis of the constituents of the wastewater discharge to assure that compliance with federal, state, and local standards are being met. The owner shall report the results of measurements and laboratory analyses to the city at such times and in such manner as prescribed by the city. The owner shall bear the expense of all measurements, analyses, and reporting requirements by the city. At such times as deemed necessary, the city reserves the right to take measurements and samples for analysis by an independent laboratory.
(K) All measurements, tests, and analyses of the characteristics of waters and wastes to which reference is made in this section shall be determined in accordance with the latest edition of Standard Methods for the Examination of Water and Wastewater, published by the American Public Health Association. Sampling methods, location, times, duration, and frequencies are to be determined on an individual basis subject to approval by the Utilities Superintendent or his or her representative.
(L) Where required by the city, the owner of any property serviced by a sanitary sewer shall provide protection from an accidental discharge of prohibited materials or other substances regulated by this section. Where necessary, facilities to prevent accidental discharges of prohibited materials shall be provided and maintained at the owner’s expense. Detailed plans showing facilities and operating procedures to provide this protection shall be submitted to the Utilities Superintendent or his or her representative for review and approval prior to the construction of the facility. Review and approval of such plans and operating procedures shall not relieve any user from the responsibility to modify the user’s facility as necessary to meet the requirements of this section. Users shall notify the Utilities Superintendent or his or her representative immediately upon having a slug or accidental discharge of substances in the wastewater in violation of this section to enable counter measures to be taken by the Utilities Superintendent or his or her representative to minimize damage to the wastewater treatment system. Such notification will not relieve any user of any liability for any expense, loss or damage to the wastewater treatment system or treatment process, or any fines imposed upon the city on account thereof under any state or federal law. Users shall insure that all employees who may cause or discover such a discharge are advised of the emergency notification procedure.
(M) No person, having charge of any building or other premises which drains into the public sewer shall permit any substance or matter which may form a deposit or obstruction to flow or pass into the public sewer. Within 30 days after receipt of written notice from the city, the owner shall install suitable and sufficient catch basin or waste trap, or if one already exists, shall clean out, repair or alter the same, and perform such other work as the Utilities Superintendent or his or her representative may deem necessary. Upon the owner’s refusal or neglect to install a catch basin or waste trap or to clean out, repair, or alter the same, after the period of 30 days, the Utilities Superintendent or his or her representative may cause such work to be completed at the expense of the owner or representative thereof.
(N) Whenever any service connection becomes clogged, obstructed, broken or out of order, or detrimental to the use of the public sewer, or unfit for the purpose of drainage, the owner shall repair or cause such work to be done as the Utilities Superintendent or his or her representative may direct. Each day after 10 days that a person neglects or fails to so act shall constitute a separate violation of this section, and the Utilities Superintendent or his or her representative may then cause the work to be done, and recover from such owner or agent the expense thereof by an action in the name of the city.
(O) The owner or operator of any motor vehicle washing or servicing facility shall provide and maintain in serviceable condition at all times a catch basin or waste trap in the building drain system to prevent grease, oil, dirt or any mineral deposit from entering the public sewer system.
(P) In addition to any penalties that may be imposed for violation of any provision of this chapter, the city may assess against any person the cost of repairing or restoring sewers or associated facilities damaged as a result of the discharge of prohibited wastes by said person and may collect such assessment as an additional charge for the use of the public sewer system or in any other manner deemed appropriate by the city.
(Q) No statement contained in this division shall be construed as preventing any special agreement or arrangement between the city and any industrial concern whereby an industrial waste of unusual strength or character may be accepted by the city for treatment, subject to payment therefore by the industrial concern, providing that National Categorical Pretreatment Standards and the city’s NPDES and/or state disposal system permit limitations are not violated.
(R) Limitations on wastewater strength:
(1) National Categorical Pretreatment Standards promulgated by the U.S. Environmental Protection Agency (EPA) pursuant to the Act shall be met by all users which are subject to such standards in any instances where they are more stringent than the limitations in this section, except as the MPCA has approved modifications of the specific limits in the National Categorical Pretreatment Standards;
(2) State requirements and limitations of discharges shall be met by all users which are subject to such standards in any instance in which they are more stringent than federal requirements and limitations or those in this section.
(Ord. 72, passed 3-3-1986)