Code of Massachusetts Regulations › 310 CMR - DEPARTMENT OF ENVIRONMENTAL PROTECTION › Title 310 CMR 15.000 - The State Environmental Code, Title 5: Standard Requirements for the Siting, Construction, Inspection, Upgrade and Expansion of On-site Sewage Treatment and Disposal Systems and for the Transport and Disposal of Septage › Subpart C - DESIGN, CONSTRUCTION, REPAIR, AND REPLACEMENT OF ON-SITE SEWAGE DISPOSAL SYSTEMS › Section 15.230 - Pretreatment Units - Grease Traps

Current through Register 1525, July 5, 2024
(1) Grease
				traps shall be provided for kitchen flows at restaurants, nursing homes,
				schools, hospitals and other facilities from which grease can be expected to be
				discharged.
(2) Grease traps shall
				be installed on a separate building sewer serving kitchen flows into which the
				grease will be discharged. The discharge from the grease trap must flow to a
				properly designed septic tank or to a building sewer prior to the septic
				tank.
(3) Grease traps shall have a
				minimum depth of four feet and a minimum capacity of 1,000 gallons, and shall
				have sufficient capacity to provide at least a 24-hour detention period for the
				kitchen flow. Kitchen flow shall be calculated in accordance with
				310 CMR
				15.203.
(4) Grease traps shall be watertight and
				constructed of the materials specified in
				310 CMR
				15.221 and
				15.226(1) and
				(2).
(5) The inlet tee shall extend to the mid
				depth of the tank. The outlet tee shall extend to within 12 inches of the
				bottom of the tank. Tees shall be Schedule 40 PVC and properly supported by a
				hanger, strap or other device.
(6)
				Grease traps shall be installed on a level stable base that has been
				mechanically compacted and onto which six inches of crushed stone has been
				placed to minimize uneven settling.
(7) Grease traps shall be provided with a
				minimum 20-inch diameter manhole frame and cover to grade over the inlet and
				outlet tees.
(8) Grease traps shall
				be accessible for inspection and maintenance. No structures shall be
				constructed directly upon or above the grease trap access locations.
(9) The invert elevation of the inlet of a
				grease trap shall be at least two inches above the invert elevation of the
				outlet. The inlet and outlet shall be located at the center line of the tank,
				and at least 12 inches above the high groundwater elevation.
(10) Backfill around the grease trap shall be
				placed in such a manner as to prevent damage to the tank.
(11) Grease traps shall be maintained in
				accordance with
				310 CMR
				15.351.
(12) Grease removal by other devices located
				within the building as part of the internal plumbing are not within the
				jurisdiction of
				310 CMR 15.000, shall not be
				considered for compliance with 310 CMR 15.230 and shall comply with the State
				Plumbing Code. Grease removal devices located outside of the building, other
				than those in compliance with 310 CMR 15.230, require the prior written
				approval of the Department.
(13)
				The Approving Authority may require that alarms and/or remote monitoring
				devices be installed and connected to grease traps.