Consequently, oil-filled electrical units are not included as bulk storage tanks or reservoirs in Attachment D . This underground storage tank, which is scheduled to be decommissioned in 1999, and its associated underground pipelines are tested periodically to ensure structural integrity. The gas turbine lube oil reservoir and the smaller no. 2 fuel oil aboveground storage tanks are steel tanks. These construction materials of these tanks are compatible with the oil stored within the tanks and with the aboveground storage conditions. Most aboveground oil storage tanks are stored within concrete block, brick, or steel secondary containment walls.
Some tanks are double-walled tanks, equipped with interstitial leak detection devices.
Certain smaller emergency generator day tanks and elevator hydraulic reservoirs are not stored within formal secondary containment berms, but are located in rooms with no floor drains. These rooms serve as secondary containment. The CUP's no. 2 fuel oil underground storage tanks are double-walled tanks and are equipped with interstitial leak detection devices. Each of these tanks is also equipped with a high-level alarm and a fill port catchment basins designed to capture minor spills or overfills. The CUP's no. 6 fuel oil underground storage vaults are not equipped with secondary containment.