(A) Grease interceptors shall be installed and maintained at the users expense, when a user operates a food service establishment. Grease interceptors may be required in noncooking or cold dairy and frozen foodstuffs establishments and other industrial or commercial establishments when the establishment generates wastewater containing fat or grease and the Director determines an interceptor is necessary to prevent contribution or accumulation of grease to the sanitary sewer collection and treatment system. Upon notification by the Director or designee that the user is subject to the terms of an enforcement action, as stipulated in the FOG enforcement response plan, said user shall not allow wastewater discharge concentration from subject grease interceptor to exceed an establishment action level of 200 milligrams per liter, expressed as hexane extractable material. All grease interceptors shall be of a type, design and capacity approved by the Director and shall be readily and easily accessible for maintenance and repair, including cleaning and for town inspection. All grease interceptors shall be serviced and emptied of accumulated waste content as required in order to maintain minimum design capability or effective volume of the grease interceptor, but not less often than every 60 days or as permitted in a valid program modification. Users who are required to pass wastewater through a grease interceptor shall:
(1) Provide for a minimum hydraulic retention time of 24 minutes at actual peak flow between the influent and effluent baffles, with 25% of the total volume of the grease interceptor being allowed for any food-derived solids to settle or accumulate and floatable grease derived materials to rise and accumulate, identified hereafter as a solids blanket and grease cap respectively.
(2) Remove any accumulated grease cap and solids blanket as required, but at intervals of not longer than 60 days at the user’s expense, or in accordance with a valid program modification or other director’s requirements. Grease interceptors shall be kept free of inorganic solid materials, such as grit, rocks, gravel, sand, eating utensils, cigarettes, shells, towels, rags and the like, which could settle into this solids blanket and thereby reduce the effective volume of the grease interceptor.
(3) If the user performs on-site grease interceptor treatment pursuant to a modification granted fewer than G.S. § 36-183(g)(5), the user shall:
(a) Prior to commencement of onsite treatment, obtain written approval by and from the Director of all processes utilized in said onsite treatment.
(b) If any pumped wastes or other materials removed from the grease interceptor are treated in any fashion on-site and reintroduced back into the grease interceptor as an activity of and after such on-site treatment, the user shall meet the criteria contained in subsection (c) below.
(c) Attain and adhere to this criteria: within and not more than 24 hours after onsite grease interceptor servicing, not more than two inches of settlable solids and/or grease shall be allowed to have accumulated therein as a result of said operations.
(4) Operate and maintain the grease interceptor to achieve and consistently maintain any applicable grease action level. CONSISTENT shall mean any wastewater sample taken from such grease interceptor must meet the terms of numerical limit attainment. If a user documents that conditions exist (“space constraints”) on their establishment site that limit the ability to locate a grease interceptor on the exterior of the establishment, the user may request an interior location for the interceptor. Such request shall contain the following information.
(5) The use of biological or other additives as a grease degradation or conditioning agent is permissible only upon prior written approval of the Director. Any user using biological or other additives shall maintain the trap or interceptor in such a manner that attainment of any grease wastewater, action level, solids blanket or grease cap criteria, goal or directive, as measured from the grease interceptor outlet or interior, is consistently achieved.
(6) The use of automatic grease removal systems is permissible only upon prior written approval of the Town Manager, the Public Works Director or the U.S. Department of Agriculture. Any user using a grease interceptor located on the interior of the site shall be subject to any operational requirements set forth by the North Carolina Division of Waste Management. Any user using this equipment shall operate the system in such a manner that attainment of the grease wastewater discharge limit, as measured from the unit’s outlet, is consistently achieved as required by the Director.
(7) The Director may make determinations of grease interceptor adequacy need, design, appropriateness, application, location, modification(s) and conditional usage based on review of all relevant information regarding grease interceptor performance, facility site and building plan review by all regulatory reviewing agencies and may require repairs to, or modification or replacement of grease interceptors.
(B) The user shall maintain a written record of grease interceptor maintenance for three years. All such records will be available for inspection by the town at all times. These records shall include:
(1) FSE name and physical location;
(2) Date of grease interceptor service;
(3) Time of grease interceptor service;
(4) Name of grease interceptor service company;
(5) Name and signature of grease interceptor service company agent performing said service;
(6) Established service frequency and type of service; full pump-out, partial pump-out, on-site treatment (type of nature of operations);
(7) Number and size of each grease interceptor serviced at FSE location;
(8) Approximated amount, per best professional judgment of contract service provider, of grease and solids removed from each grease interceptor;
(9) Total volume of waste removed from each grease interceptor;
(10) Destination of removed wastes, food solids and wastewater disposal;
(11) Signature and date of FSE personnel confirming service completion; and
(12) Such other information as required by Director.
(C) A user may request a modification to the following requirements of this subchapter. Such request for a modification shall be in writing and shall provide the information set forth below.
(1) The user’s grease interceptor pumping frequency. The Director may modify the 60-day grease interceptor pump-out frequency when the user provides data and performance criteria relative to the overall effectiveness of a proposed alternate and such can be substantiated by the Director. Proposed alternatives may include: grease interceptor pumping or maintenance matters, bioremediation as a complement to grease interceptor maintenance, grease interceptor selection and sizing criteria, onsite grease interceptor maintenance, and specialized ware washing procedures
(2) Grease interceptor maintenance and service procedures. The Director may modify the method(s) or procedure(s) utilized service a grease interceptor when the user provides data, and performance criteria relative to the overall effectiveness of a proposed alternate method or procedure and such can be substantiated by the Director. If a modification to maintenance and service procedures is permitted it shall be a conditional discharged permit approval.
(3) Any modification must be approved by the Director in written form before implementation by the user or the user’s designated service provider. The user shall pay modification fees as set forth in the budget ordinance fee schedule.
(Ord. O-2007-10, passed 6-5-2007)