(A) Maintenance requirements.
(1) FSEs shall not have staff clean out the GRD as a substitute for a professional grease waste hauler. If a FSE utilizes an automatically or mechanically cleaning GRD, its staff shall properly maintain.
(2) All GRDs shall be kept in good repair, functioning properly and shall be maintained in continuous operation according to manufacturer’s guidelines and the City’s requirements.
(3) Sewer lines to and from GRDs shall be kept in good repair and clear of any buildup of FOG that could potentially contribute to backups and/or SSOs.
(4) All FOG discharged during GRD or sewer line cleaning and maintenance shall be captured. Any FSE that has their kitchen grease waste lines, exit lines from a GRD and/or laterals cleaned by jetting or hydro flushing shall have the contractor capture the contents removed from the line to prevent SSOs, depending on the main size that the lateral feeds into. All contents removed from sewer lines shall be contained and disposed of properly by a licensed contractor.
(5) No additives may be introduced to the GRDS or a FSEs wastewater system for the purpose of emulsifying FOG or biologically/chemically treating FOG for grease remediation or as a supplement to interceptor maintenance unless a specific written authorization from the City is obtained. Systems or additives, such as solvents or enzymes that dissolve or mobilize FOG are prohibited.
(6) All GRDS shall be completely cleaned out by a registered waste hauler prior to the closure of an FSE, the associated building or a change in ownership.
(B) GRD maintenance frequency.
(1) The maintenance frequency shall be set so as to ensure that the minimum hydraulic retention time and available hydraulic volume is maintained to effectively intercept and retain FOG and minimize the passage of FOG to the sanitary sewer collection system. The maintenance frequency for all FSEs with a GRD shall be determined by one of the following methods:
(a) GRDS shall be fully pumped out and cleaned at a frequency such that the combined FOG and solids accumulation does not exceed 25% of the total design hydraulic depth in any location of the GRD. The 25% rule shall apply to all GRDS.
(b) The entire contents of all grease interceptors (gravity grease interceptors) and GRDs greater than 100 gallons shall be removed every three months or more frequently as to prevent FOG from entering the sanitary sewer.
(c) The entire contents of all grease traps (hydro mechanical grease interceptors) shall be removed every month or more frequently as to prevent FOG from entering into the sanitary sewer.
(d) The entire contents of all automatically or mechanically cleaning GRD shall be removed every six months or more frequently as to prevent FOG from entering into the sanitary sewer.
(2) The maintenance frequency may be adjusted when sufficient data have been obtained to establish an appropriate frequency based on the guidelines adopted pursuant to the FOG program.
(a) The City may modify the maintenance frequency at any time to reflect changes in actual operating conditions in accordance with the FOG program. Based on the actual generation of FOG from the FSE, the maintenance frequency may increase or decrease.
(b) The owner/operator of a FSE may submit a request to the City requesting a change in the maintenance frequency at any time. The FSE has the burden of responsibility to demonstrate that the requested change in frequency reflects actual operating conditions based on the average FOG accumulation over time and meeting the requirements described in subsection (B)(1)(a), and that it is in full compliance with the conditions of this ordinance. Upon determination by the City that the requested revision is justified accordingly to reflect the change in maintenance frequency.
(c) If the GRD, at any time, contains FOG and solids accumulation that does not meet the requirements described in subsection (B)(1)(a), the FSE shall have the GRD serviced immediately such that all FOG, solids, and other materials are completely removed from the GRD.
(Ord. 4620, passed 10-28-13)