US Patent 6935161 Service station leak detection and recovery system

A fueling environment distributes fuel from a fuel supply to fuel dispensers in a daisy chain arrangement with a double-walled piping system. Fuel leaks that occur within the double-walled piping system are returned to the underground storage tank or a sump proximate the submersible turbine pump by the outer wall of the double-walled piping. This preserves the fuel for later use and helps reduce the risk of environmental contamination. Leak detectors may also be positioned in to fuel dispensers detect leaks and provide alarms for the operator, and help pinpoint leak detection that has occurred in the piping system proximate to a particular fuel dispenser or in between two consecutive fuel dispensers.