Section 658-8-9 - Oil Supply Tanks8.9.1Inside Tank FabricationRectangular built-in place tanks shall be fabricated using one-quarter (1/4) inch minimum thick steel sheets reinforced on maximum 24-inch centers. Tank bottoms must be supported on 12-inch-wide non-combustible piers, to a height of 8 inches above the floor. All welding must be performed by a welder. Tanks must be designed by a registered engineer who shall observe the tank under 5 PSI test and certify to it being tight under this test.
8.9.2Manholes8.9.2.1 Manholes, sixteen (16) inches in diameter or larger, must be installed in the top of all tanks of 5,000 gallons or more.8.9.2.2 Manholes provided in 5,000 gallons supply tanks must be liquid tight when installed inside of a structure.8.9.2.3 Manholes, when required for outside use, may take the form of a floating lifter roof or weak roof-to-shell seam, or other approved pressure relieving construction.8.9.3Separation from Other AppliancesAll fuel oil supply tanks must be a minimum of five (5) feet from any gas and/or solid fuel burning appliance.
8.9.4Tank Requirements Upon Conversion to an Alternative FuelIf an oil burning appliance is converted to an alternative fuel, but the tank is left in place so that it can be returned to service at some future date, all of the following requirements must be met before the alternative fuel is used:
8.9.4.1 The vent piping must remain intact and open to the outside of the building;8.9.4.2 The fill pipe must be removed completely, and the tank must be plugged with a threaded malleable iron plug;8.9.4.3 The burner supply line must be removed and the valves on both the tank and burner must be capped or plugged; and8.9.4.4 If an underground oil supply line is in use and complies with Section 8.9 of this Chapter, it may remain in place provided that all of the following conditions are met: 1. The oil line is emptied of its contents;2. The oil line is disconnected from the oil tank and burner; and3. The oil line is plugged on both ends in addition to the burner and tank fittings being plugged. Oil can remain in the tank unless prohibited by the local Authority Having Jurisdiction or the Maine Department of Environment Protection.
8.9.5Fuel Supply Systems That Are Permanently Taken Out of ServiceIf a fuel supply tank is permanently removed from service for whatever reason, the tank and all piping connected to it, including the outside fill and vent piping and any supply piping connected to the appliance, shall be:
1. Emptied of all liquid contents and sludge;2. Cleaned and rendered free of combustible vapors;3. Removed from the premises or property; and4. Properly disposed of in accordance with all applicable local, state, and federal rules and regulations.