In a geomembrane defined impoundment, a leak is located by vessel supported means. The present invention is directed to locating the vessel so as to then locate the leak. A set of N hydrophones spaced around the impoundment detect a liquid transmitted acoustic pulse from the vessel. The vessel supports an RF transmitter which broadcasts a timing pulse. With the timing pulse, elapsed acoustic travel time is measured to define range in the liquid. The range defines an arc of a circle around a single hydrophone. Using N hydrophones, N arcs are defined on the impoundment, each centered on the respective hydrophones, to intersect at the vessel location.
Thomas E. Owen