(a) Grease/oil interceptors shall be installed by users as required by subsection (b) hereof or when liquid wastes contain an excess of 100 mg/l of grease or contain substances which may solidify or become viscous at temperatures between thirty-two degrees Fahrenheit (32º F) or zero degrees Centigrade (0º C) or one hundred fifty degrees Fahrenheit (150º F) or sixty-five degrees Centigrade (65º C), except that such interceptors shall not be required for single family or multifamily dwelling units unless problems occur at particular locations more than twice in a twelve-month period. Grease/oil interceptors shall be installed at the user’s expense.
(b) Grease/oil interceptors shall be required at all facilities which provide food service and/or preparation activities, including, but not limited to, full service restaurants, fast food establishments, delicatessens, cafeterias, (including church and school facilities where commercial equipment is installed and the square footage and/or frequency of use indicates more than occasional use), meat distributors, food processing facilities, grocery stores with food preparation/service areas, bakeries, caterers, and/or other similar types of operations.
(c) All grease/oil interceptors shall be a type, design and capacity approved by the General Manager and shall be readily accessible for user cleaning and Sanitary Board inspection.
(d) Grease/oil interceptors shall provide for a minimum hydraulic retention time of twenty-four minutes at actual peak flow (or otherwise calculated based on the Uniform Plumbing Code) between the influent and effluent baffles with twenty percent (20%) of the total volume being allowed for sludge to settle and accumulate.
(e) Access manholes, with a minimum diameter of twenty-four inches, shall be provided over each chamber and sanitary tee. The access manholes shall extend at least to finished grade and be designed and maintained to prevent water inflow or infiltration. The manholes shall also have readily removable covers to facilitate inspection, grease removal, and wastewater sampling activities.
(f) Grease/oil interceptors shall be constructed of impervious materials capable of withstanding abrupt and extreme changes in temperatures. They shall be of substantial construction, watertight and equipped with easily removable covers which, when bolted in place, shall be gastight and watertight. Each user shall provide protection against accidental discharge of grease and oil. Features which prevent accidental discharge of these materials shall be provided and maintained at the user’s expense. Facilities and operating procedures to provide this protection shall be submitted to the Sanitary Board for review and approval prior to construction of the facility. Review and approval of such plans and operating procedures shall not relieve the user of the responsibility to modify its facility as necessary to meet the requirements of this article.
(g) The General Manager shall make determinations of interceptor need and/or adequacy based on review of all relevant information regarding interceptor performance, facility site, and building plan review. The General Manager may require repairs to, or modifications or replacement of interceptors when deemed necessary.
(h) A food service and/or preparation facility which demonstrates that the discharge from its food service and/or preparation activities contains less than 100 mg/l of grease, may receive an exemption from minimum sizing requirements or installation and maintenance requirements. The sampling and testing to demonstrate the concentration of grease in the discharge must be conducted, at the facility’s expense, by an independent testing organization and measured in accordance with the analytical test procedures established in 40 CFR 136 as amended.
(i) If an establishment desires, because of documented space constraints, an alternate to an interceptor located outside the building, a written request may be made including location of sewers and easements in relation to available exterior space and existing plumbing at or in a site that uses common plumbing for all services.
(j) Except as provided herein, for a period of one year following adoption of this article, although installation of interceptors will be required to be installed, no enforcement actions will be taken for failure to achieve limits on discharges unless an event occurs that causes an adverse impact on the Publicly Owned Treatment Works or the environment. In such case, the Sanitary Board may take enforcement actions as stipulated by the City’s Pretreatment Ordinance. (Ord. 2034. Passed 11-6-03.)