Half Moon Bay Municipal Code § 13.22.300 Installation of grease, oil and sand control devices (common areas and…

A. Except as provided for in Sections 13.22.380 and 13.22.390, any structure designed for or intended to be used for an FSE or FM/P must have an approved grease interceptor/trap installed prior to discharging any wastewater into the city's public sewer collection system.

B. Property owners of new construction of a commercial structure designed to house multiple tenants on a single parcel shall be responsible to install and maintain a single grease interceptor to serve each individual tenant unless a property owner demonstrates to the public works director that it is not practically possible to install and maintain a single grease interceptor to serve each individual unit located in the structure in which case the public works director has the discretion to approve a plan for such structure providing for more than one grease interceptor or a combination of grease interceptors to service such property, which approval shall be in writing. Said approved plan shall include the minimum number of grease interceptors that can reasonably serve the structure and shall specifically include service for all approved grease interceptors.

C. The owner of any structure occupied by one or more FSEs or FM/Ps shall be jointly and severally liable with the owner of each FSE or FM/P served by any grease interceptor for the servicing and maintenance of that grease interceptor and for any servicing and maintenance required of any wastewater facility located downstream from said structure to remove any accumulations of FOG therefrom if the owner or FSE is found to be noncompliant with the provisions of this chapter and/or to have contributed to the partial or complete obstruction of a wastewater facility located downstream.

D. The public works director may require existing FSEs or FM/Ps and owners of structures in which such FSE or FM/Ps are located which have been identified as introducing FOG into any portion of the city's public sewer collection system, and which introduction of FOG, in whole or in combination with other FOG contributors, has been responsible for causing the need for the city to clean such portion of the wastewater system more than once in a single calendar year to install grease interceptors or other FOG equipment as deemed necessary to comply with this section. Such installation shall be completed and operational within one hundred eighty days of notice by the public works director.

(Ord. C-2023-03 § 2 (Att. A), 2023)

A. Any food service establishment, or other type of business or establishment where grease or other viscous, obstructing, or objectionable materials may be discharged into a public sewer shall have a grease control device and related plumbing of a size and design approved by the public works director or designee.

B. Waste discharge from fixtures and equipment in establishments which may contain grease or other objectionable materials including, but not limited to, scullery sinks, pot and pan sinks, food waste disposals, soup kettles, and floor drains located in areas where such objectionable materials may exist, shall be drained into the public sewer collection system through the grease control device unless otherwise approved by public works provided, however, that toilets, urinals, wash basins, and other fixtures containing fecal material shall not flow through the grease control device.

C. Automatic dishwashers may only be connected to grease control devices on a case-by-case basis as approved by the public works director.

D. Trash enclosures, car washes, automotive repair businesses and other facilities where grit, oil or other objectionable materials may be discharged into a public or private sewage main or disposal system shall have a sand control device and related plumbing of a size and design approved by the public works director or designee.

E. The city reserves the right to make determinations of grease and sand control device size, adequacy, location and need, based on building code requirements and review of relevant information, including, but not limited to, grease trap and/or interceptor performance, waste stream characteristics, facility location, maintenance needs, and/or inspection needs.

F. Grease and sand interceptors shall meet the following minimum requirements:

1. All FSEs and commercial and industrial entities with the potential to discharge FOG, sand or grit into the city's public sewer collection service area are required to have a minimum one thousand gallon grease/sand interceptor. Larger interceptors shall be sized according to the latest building/plumbing codes and shall provide at least thirty minutes of retention time.

G. Grease traps are allowed on a case-by-case basis only. Upon approval of the public works director, grease traps shall meet the following minimum requirements:

1. The maximum allowable size of grease trap shall be flow rate of twenty-five gpm (or fifty pounds grease retention). City will provide the size requirements;

2. Type of grease trap shall be hydromechanical grease device, conforming to ASME A12.14.3 or PDI-G 101 and type/brand shall be approved by the public works department and the city building department official and installed per manufacturer's specifications; and

3. Traps must meet applicable requirements of the state plumbing and building codes.

H. Each grease/sand interceptor shall be so installed and connected that it shall be at all times easily accessible for inspection, sampling, cleaning and removal of grease, and other matter from all surfaces. The public works director or their agent will approve locations of all grease/sand interceptors by acknowledging and signing the design plans.

I. Discharger shall not install any device without the approval of the public works director and the issuance of a building permit.

J. A grease control device should be situated on the wastewater discharger's premises except when such a location would be impractical or cause undue hardship on the wastewater discharger. The city may, subject to the issuance of an encroachment permit by the city, allow the device to be installed in the public street or sidewalk area and located so that it will not be obstructed by landscaping or parked vehicles.

(Ord. C-2023-03 § 2 (Att. A), 2023)

A. Maintenance and Cleaning of Grease and Sand Interceptors. The twenty-five percent rule requires that the depth of oil and grease (floating and settled) in a sand or grease interceptor shall be less than twenty-five percent of the total operating depth of the interceptor. The operating depth of the interceptor is determined by measuring the internal depth from the outlet water elevation to the bottom of the interceptor.

B. Disposal. In the maintaining and routine cleaning of grease interceptors and any other grease control device, the owner of the FSE or FM/P and the owner of the structure in which it is located, if different from the owner of the FSE or FM/P, shall be jointly responsible for the proper removal and disposal by appropriate means of the captured material. If not performed by personnel under the direct control and direction of any such owner/manager, such removal and haul shall be performed by currently licensed waste disposal haulers.

C. Outdoor Grease and Sand Interceptors. Maintenance of outdoor grease and sand interceptors shall be performed as frequently as necessary to protect the public sewer collection system against the accumulation of FOG and insoluble wastes. Maintenance shall be performed as determined by inspection and application of the twenty-five percent rule. Inspection and maintenance shall be performed at least every ninety days.

D. Indoor Grease Traps. Maintenance of indoor grease traps shall be performed as frequently as necessary to protect the public sewer collection system against the accumulation of FOG and insoluble wastes. Maintenance shall be performed as required by inspection and/or sampling. Maintenance shall be performed at least every fourteen days.

E. Maintenance Process. Maintenance process shall include the following minimum services:

1. Complete removal of all grease interceptor or trap contents rather than skimming the top grease layer;

2. Thorough cleaning of the grease interceptor or trap to remove grease and scum from inner walls and baffles;

3. Filling cleaned interceptor or trap with cold potable water;

4. Completing waste hauler's section of the grease disposal manifest form and delivery to waste disposal site along with the grease interceptor or trap waste;

5. Top skimming, decanting or back flushing of the grease interceptor or trap or its contents for the purpose of reducing the volume of waste to be hauled is prohibited. Vehicles capable of separating water from grease shall not discharge separated water into the grease trap or into the public sewer collection system.

F. Maintenance Modifications. Food service facilities which operate infrequently or only for special events may request a modification to the maintenance schedule specified above. The public works director may authorize a maintenance frequency related to the operation of the food service facility. The food service facility shall submit a request for a modified maintenance schedule which includes all details of operation for the public works director to review.

G. Disposal. The wastewater discharger shall be responsible for the proper removal and disposal of the grease interceptor or trap waste. All waste removed from each grease interceptor or trap must be disposed of properly at an appropriate facility designed to receive grease interceptor or trap waste. No grease interceptor or trap waste shall be discharged into any city sanitary or storm sewer system.

H. Maintenance Log. The user shall be responsible for retaining a maintenance log with records of the maintenance of grease interceptors and traps including manifests, permits, permit applications, correspondence, sampling data and any other documentation that may be requested by the city. This log shall include the dates of service, volume of waste removed, waste hauler, and disposal site of waste. These records shall be kept on site at the location of the grease interceptor or trap for a period of three years and are subject to review without prior notification. Wastewater dischargers shall maintain records on site for a period of at least three years as follows:

1. Wastewater dischargers with an installed grease control device shall maintain records showing that the control device has been properly maintained and cleaned as required by this section; and

2. Food service establishments shall maintain records showing the following related to all grease hauled off site: date and time material removed off site; volume removed; hauler name; truck license number; type of grease removed; and final destination of material collected.

(Ord. C-2023-03 § 2 (Att. A), 2023)

A. If the owner of any FSE or FM/P or of any structure in which an FSE or FM/P is located or is to be located demonstrates to the reasonable satisfaction of the public works director that installation of a grease interceptor/trap is not feasible, the public works director may grant an exception allowing such owner to install grease traps or other alternative treatment technology which will in the discretion of the public works director adequately control the release of FOG from the FSE or FM/P or the structure into the public sewer collection system. The FSE or FM/P bears the burden of demonstrating that the installation of a grease interceptor/trap is not feasible. The request for an exemption shall include the following information if relevant:

1. Evidence of a lack of available exterior space necessary to place an interceptor/trap relative to the location of sewer main and easement;

2. Evidence of a lack of adequate slope for gravity flow between kitchen plumbing fixtures in the FSE or FM/P and the wastewater facilities;

3. Description and specifications of the alternative grease control equipment that will be installed and evidence that the alternative pretreatment technology is equivalent to or better than a grease control device in controlling its FOG discharge;

4. Evidence that the size, available seating or type of food preparation does not generate any significant volume of FOG; and

5. The FSE must be able to demonstrate, after installation of the proposed alternative pretreatment, its effectiveness to control FOG discharge through downstream visual monitoring of the public sewer collection system at its own expense.

(Ord. C-2023-03 § 2 (Att. A), 2023)

A. A waiver from installation of a grease or sand control device may be granted to an FSE that has been determined to have negligible FOG discharge and insignificant impact to the city's public sewer collection system. The city's determination to grant or revoke a waiver shall be based upon, but not limited to, evaluation of the following conditions:

1. City determination of quantity of FOG discharge as measured or as indicated by the size of the FSE based on seating capacity, number of meals served, menu, water usage, amount of on-site consumption of prepared food and other conditions that show contribution to FOG discharges;

2. City determination that adequacy of implementation of BMP and compliance history are sufficient;

3. City determination that sewer size, slope, condition based on visual information, FOG deposition in the sewer by the FSE, and history of maintenance and sewage spills in the receiving sewer system;

4. City determination that the changes in operations significantly reduce FOG discharge; and

5. Any other condition the city deems reasonably related to the generation of FOG discharges.

(Ord. C-2023-03 § 2 (Att. A), 2023)