Section 250-RICR-150-10-6.26 - Grease TanksA. See § 6.62 of this Part, Figure 4.B. Required Use - Grease tanks shall be installed in accordance with the following: 1. OWTS Applications for New Building Construction for restaurants and other facilities that prepare food shall have kitchen wastes separately plumbed to an external grease tank;2. OWTS Applications for Alterations to a Structure and OWTS Applications for Repair for restaurants and other facilities that prepare food with a total design flow equal to or exceeding two thousand (2,000) gallons per day shall have kitchen wastes separately plumbed to an external grease tank; and3. OWTS Applications for Alterations to a Structure and OWTS Applications for Repair for restaurants and other facilities that prepare food with a total design flow less than two thousand (2,000) gallons per day shall have kitchen wastes separately plumbed to an external grease tank or have an internal grease removal unit installed.C. Capacity - Grease tanks shall have a minimum capacity of one thousand (1,000) gallons, and shall have sufficient capacity to provide at least a twenty-four (24) hour detention period for fifty percent (50%) of the design flow for the OWTS.D. Construction - Grease tanks shall be watertight, meet the construction and material standards required for septic tanks in § 6.27(C) of this Part, and be shaped as required for septic tanks in § 6.27(D) of this Part.E. Inlet and Outlet - The inlet and outlet shall be as required for septic tanks in § 6.27(F) of this Part. Grease tanks shall be provided with inlet tees and outlet tees. Baffles may be provided as necessary in conjunction with tees to maximize the separation of grease from the wastewater.1. Tees shall be minimum SDR 35 PVC solvent welded and properly supported by a hanger, strap or other device.2. The inlet tee shall extend to the mid-depth of the tank. The outlet tee shall extend to twelve inches (12") from the bottom of the tank.3. The tops of the tees shall extend a minimum of six inches (6") above the flow line, and shall be left open to provide ventilation. There shall be an air space of at least three inches (3") between the tops of the tees and the top interior of the grease tank.F. Access Openings - Grease tank access openings shall be as required for septic tanks in § 6.27(H) of this Part. In addition, the lid shall specify that it is for a grease tank.G. Location - Grease tanks shall be installed on a separate building sewer serving that part of the plumbing system into which the grease shall be discharged. The discharge from the grease tank shall flow to a properly designed septic tank.H. Installation - Grease tank installation shall be as required for septic tank installation in § 6.27(J) of this Part.I. Grease Tanks in Series - Grease tanks may be placed in series provided that the combined volume meets the requirements of § 6.26(C) of this Part and that each grease tank meets all other requirements of § 6.26 of this Part. In no case shall more than two (2) grease tanks be placed in series.J. Performance Testing - Grease tanks shall be certified watertight in accordance with § 6.27(L) of this Part.K. Maintenance - Grease tanks shall be cleaned by a licensed permitted septage hauler when twenty-five percent (25%) of the liquid volume is filled with grease.L. Existing Grease Tanks - Grease tanks in place as of January 1, 2008 that have access openings to finished grade shall be in compliance with § 6.27(H)(2) of this Part no later than January 1, 2013.250 R.I. Code R. 250-RICR-150-10-6.26
Amended effective 11/25/2018
Amended effective 12/28/2021
Amended effective 7/1/2022