Secondary containment system for an above-ground petroleum storage tank

摘要

A secondary containment system for an above-ground petroleum storage tank includes a berm rising above the ground surrounding the tank and spaced apart from the tank for defining a petroleum retention basin about the tank. An impermeable liner covers the ground between the tank and the berm. At least one drain is formed through the liner and into the underlying ground. A hydrocarbon sensor monitors the presence of petroleum in the drain. A control device responds to the presence of petroleum in the drain by closing a containment valve to prevent discharge of petroleum from the basin. An indicator device provides at least one of an audible and visible signal indicating that petroleum is sensed in the drain.