§ 53.21 PRETREATMENT.
   (A)   Federal pretreatment standards. Federal pretreatment standards promulgated by the United States Environmental Protection Agency (EPA) pursuant to the Act shall be met by all users which are subject to the standards in any instance where they are more stringent than the limitations in this section unless the city had applied for and obtained from the MPCA approval to modify the specific limits in the federal pretreatment standards. When requested, an application for modification of the federal pretreatment standards will be considered for submittal by the city when its wastewater treatment system achieves consistent removal of the pollutants. CONSISTENT REMOVAL shall mean reduction in the amount of pollutant or alteration of the nature of a pollutant which is in the influent to the wastewater treatment system to a less toxic or harmless state by the time it is discharged in the effluent. The reduction or alteration will be demonstrated by averaging the lowest 50% of the removals measured by 12 or more samples according to the procedures set forth in 40 C.F.R. § 403.7(c)(2) of the "General Pretreatment Regulations for Existing and New Sources of Pollution."
   (B)   State requirements. State requirements and limitations on discharges shall be met by all users which are subject to those standards in any instance in which they are more stringent than federal requirements and limitations or those in this section.
   (C)   Industrial pretreatment requirements. Industrial users shall provide necessary wastewater pretreatment as required to comply with this section and shall achieve compliance with all federal categorical pretreatment standards within the time limitations as specified by the federal pretreatment regulations. Any facilities required to pretreat wastewater to a level acceptable to the city shall be provided, operated and maintained at the user's expense. Detailed plans showing the pretreatment facilities and operating procedures shall be submitted to the city for review at least 60 days before construction and shall be approved by the city. The city may also require the industry to submit a schedule of compliance indicating dates by which federal, state and local pretreatment standards would be achieved. The review of the plans and operating procedures will in no way relieve the user from the responsibility of modifying the facility as necessary to produce an effluent acceptable to the city under the provisions of this section. Any subsequent changes in the pretreatment facilities or method of operation shall be reported to and be acceptable to the city prior to the user's initiation of the changes. All records relating to compliance with pretreatment standards shall be made available by the city to officials of the EPA or MPCA upon request.
   (D)   Sludges generated. Sludges, floats, skimmings and the like generated by an industrial or commercial pretreatment system shall not be placed into the city's wastewater disposal system. The sludges shall be contained, transported and disposed of in accordance with all federal, state and local regulations. Any removal and hauling not done by the owners' own personnel shall be performed by a licensed waste disposal firm.
(Prior Code, § 3.20, Subd. 3G)