(A) Whenever deemed necessary, the Public Works Director may require users to restrict their discharge during peak flow periods, designate that certain wastewater be discharged only into specific sewers, relocate and/or consolidate points of discharge, separate sewage wastestreams from industrial wastestreams, and any other conditions as may he or she necessary to protect the wastewater treatment system and determine the user’s compliance with the requirements of this subchapter.
(B) The Public Works Director may require any person discharging into the wastewater treatment system to install and maintain, on their property and at their expense, a suitable storage and flow-control facility to ensure equalization of flow. A wastewater discharge permit may be issued solely for flow equalization.
(C) Sand interceptors shall be provided when in the opinion of the Public Works Director, they are necessary for the proper handling of wastewater containing excessive amounts of sand; except that those interceptors shall not be required for residential users. All interception units shall be of the type and capacity approved by the Public Works Director, and shall be so located to be easily accessible for cleaning and inspection. These interceptors shall be inspected, cleaned, and repaired regularly, as needed, by the user at their expense.
(D) Users with the potential to discharge flammable substances may be required to install and maintain an approved combustible gas detection meter. In the event gas is detected, user must take appropriate steps to eliminate the presence of gas in the system,
(E) Grease interceptors shall be installed by all grease generating establishments as required by the Public Works Director. Grease interceptors shall be installed at the grease generating establishment’s expense. No grease generating establishment shall allow wastewater discharge concentration from subject grease interceptor to exceed 200 milligrams per liter, as identified by method EPA Method 1664. All grease interceptors shall be of a type, design, and capacity approved by the Public Works Director, his or her designee, and shall be readily and easily accessible for user cleaning and 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 30 days or at a different intervals as authorized by the Public Works Director. Users who are required to pass water through a grease interceptor shall:
(1) Provide for a minimum hydraulic retention time of 24 minutes at actual peak flow or 12 minutes at the calculated theoretical peak flow rate as predicted by the Uniform Plumbing Code fixture criteria, between the influent and effluent baffles with 20% of the total volume of the grease interceptor being allowed for sludge to settle and accumulate, identified hereafter as a “sludge pocket.”
(2) Remove any accumulated grease cap and sludge pocket as required, but at intervals of not longer than 30 days, or at a different interval as authorized by Public Works Director, or the Public Works Director’s designee, at the users expense. 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 pocket and thereby reduce the effective volume of the grease interceptor.
(3) Accept the following conditions: if any skimmed or pumped wastes or other materials removed from grease interceptor are treated in any fashion onsite and reintroduced back into the grease interceptor as an activity of and after the onsite treatment, the grease generating establishment shall be responsible for the attainment of established grease numerical limit consistent with and contained in division (E) above on all discharges of wastewater from the grease interceptor into the town’s sanitary sewer collection and treatment system.
(4) Operate the grease interceptor in a manner so as to maintain the device so that attainment of the grease limit is consistently achieved. “Consistent” shall mean any wastewater sample taken from the grease interceptor shall be subject to terms of numerical limit attainment described in division (E) above. If an establishment desires, because of documented space constraints, an alternate to an out-of-building grease interceptor, the request for an alternative location shall contain the following information:
(a) Location of town sewer main and easement in relation to available exterior space outside building; or
(b) Existing plumbing at or in a site that uses common plumbing for all services it that site.
(5) Understand and agree that the use of biological additives as a grease degradation agent is conditionally permissible, upon prior written approval by the Director. Any establishment using this method of grease abatement shall maintain the trap or interceptor in a manner that attainment of the grease wastewater discharge limit, as measured from the trap’s outlet, is consistently achieved.
(6) Understand and agree that the use of automatic grease removal systems is conditionally permissible, upon prior written approval by the Public Works Director, the Inspection Superintendent of the Town of Fairmont, and the Robeson County Department of Health. Any establishment 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.
(7) Understand and agree that the Public Works Director reserves the right to make determinations of grease interceptor adequacy and need, based on review of all relevant information regarding grease interceptor performance, facility site and building plan review and to require repairs to or modification or replacement of the traps.
(8) Upon the prior written approval of the Public Work Director, non-cooking establishments may be exempted from the requirements of this subchapter after an inspection of the subject premises and submission of adequate supporting documentation, as deemed necessary in the sole and absolute discretion of the Public Works Director. At a minimum, the supporting documentation shall include: blue prints at the subject premises; and a full and detailed list of all potential sources of grease at the subject premises.
(9) Grease traps and interceptors may also be required in other facilities, as deemed necessary by the town’s Public Works Director.
(10) In the event an overflow, spill, leak, or other event causes an environmental impact that may be attributed in part or in whole to a particular user, the town will seek enforcement action under the sewer use ordinance, and/or the pretreatment enforcement plan. For purposes of this section an overflow, spill, leak or other event shall be deemed to have all environmental impact when:
(a) The overflow or other event reaches an amount of wastewater equal to or in excess of 1,000 gallons; or
(b) Any amount of wastewater reaches any body or surface water.
(11) (a) Users shall supply:
1. An adequate sampling point down stream of grease trap or interceptor, prior to mixing with other sanitary flows; and
2. An accessible entry into each chamber of the grease trap or interceptor.
(b) The minimum requirement for the sampling point shall be a 4-inch vertical clean out.
(12) Access manholes, with a minimum diameter of 24 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. All manhole construction shall conform to the Town of Fairmont’s specifications.
(13) Users shall empty and service grease traps and interceptors to comply with the performances criteria in § 50.72 as often as necessary, but in any event no longer than every 30 days. Under-the-counter types of grease traps and interceptors shall be cleaned at least daily, and shall comply with the performance criteria of § 50.72. There shall be no reintroduction of wastewater back into the grease trap or interceptor unless and until the wastewater has been proven to contain 200 mg/l or less of grease. Under no circumstances shall the sludge or scum layer be reintroduced or discharged into the town’s wastewater collection system or POTW.
(F) The user shall maintain a written record of trap maintenance for 3 years. All records will be available for inspection by town officials or the Public Works Director, at all times.
(G) No non-grease laden sources are allowed to be connected to sewer lines intended for grease interceptor service.
(H) Users shall design and build the grease interceptors for new construction and new food service establishments in existing buildings to the construction standards for new facilities or new food service establishments in existing buildings found In the North Carolina State Building Code, for Plumbing.
(Ord. passed 06-101, 4-18-2006)