§ 21-59. Pretreatment of wastewater.

(a) Pretreatment facilities. Industrial users shall provide necessary wastewater treatment as required to comply with this ordinance and shall achieve compliance with all categorical pretreatment standards, local limits and the prohibitions set out in section 21-59(a) above within the time limitations specified by the EPA, the state, or the city whichever is more stringent. Any facilities required to pretreat wastewater to a level acceptable to the city shall be provided, operated, and maintained at the industrial user's expense. Detailed plans showing the pretreatment facilities and operating procedures shall be submitted to the city for review, and shall be acceptable to the city before construction of the facility. The review of such plans and operating procedures will in no way relieve the industrial user from the responsibility of modifying the facility as necessary to produce an acceptable discharge to the city under the provisions of this ordinance. 
(b) Additional pretreatment measures.

(1) Whenever deemed necessary, the Superintendent may require industrial users to restrict their discharge during peak flow periods, designate that certain wastewater be discharged only into specific sewer, relocate and/or consolidate points of discharge, separate sewage wastestreams from industrial wastestreams, and such other conditions as may be necessary to protect the WWTP and determine the industrial user's compliance with the requirements of this ordinance. 
(2) Grease, oil and sand interceptors shall be provided when, in the opinion of the Superintendent, they are necessary for the proper handling of wastewater containing excessive amounts of grease and oil, or sand; except that such interceptors shall not be required for residential users. All interception units shall be of type and capacity approved by the Superintendent and shall be so located to be easily accessible for cleaning and inspection. Such interceptors shall be inspected, cleaned, and repaired regularly as needed, by the owner at his expense. 
(3) Industrial users with the potential to discharge flammable substances may be required to install and maintain an approved combustible gas detection meter. 
(4) At no time shall two readings on an explosion hazard meter at the point of discharge into the WWTP, or at any point in the WWTP, be more than five (5) percent nor any single reading over ten (10) percent of the lower explosive limit (LEL) of the meter. 

(c) Accidental discharge/slug control plans. The Superintendent may require any industrial user to develop and implement an accidental discharge/slug control plan. At least once every two (2) years. The Superintendent shall evaluate whether each significant industrial user needs such a plan. New significant industrial users must be evaluated within one (1) year of being designated as a significant industrial user. Any industrial user required to develop and implement an accidental discharge/slug control plan shall submit a plan which addresses, at a minimum, the following: 

(1) Description of discharge practices, including non-routine batch discharges. 
(2) Description of stored chemicals and containment areas. 
(3) Procedures for immediately notifying the WWTP of any accidental or slug discharge. Such notification must also be given for any discharge which would violate any of the prohibited discharges in section 21-59(a) of this ordinance. 
(4) Procedures to prevent adverse impact from any accidental or slug discharge. Such procedures include, but are not limited to, inspection and maintenance of storage areas, handling and transfer of materials, loading and unloading operations, control of plant site run-off, worker training, building of containment structures or equipment, measures for containing toxic organic pollutants (including solvents, and/or measures and equipment for emergency response). 

(d) Tenant responsibility. Where an owner of property leases premises to any other person as a tenant under any rental or lease agreement, if either the owner or the tenant is an industrial user, either or both may be held responsible for compliance with the provisions of this ordinance. 
(e) Hauled wastewater.

(1) Septic tank waste may be accepted into the WWTP at a designated receiving structure within the treatment plant area, and at such times as are established by the Superintendent, provided such wastes do not violate section 21-59 of this ordinance or any other requirements established or adopted by the city. Wastewater discharge permits for individual vehicles to use such facilities shall be issued by the Superintendent. 
(2) The discharge of hauled industrial wastes as "industrial septage" requires prior approval and a wastewater discharge permit from the city. The Superintendent shall have authority to prohibit the disposal of such wastes, if such disposal would interfere with the treatment plant operation. Waste haulers are subject to all other sections of this ordinance. 

(Ord. No. 2022-49, § 1, 11-01-22)