Ground-Penetrating Radar (GPR) is a nondestructive method that uses radar pulses to image the subsurface. With GPR, the radar signals are directed into the ground causing subsurface objects to be reflected and then are picked up by the receiver. The travel time of the reflected signal indicates the depth.
GPR is used to detect subsurface objects, changes in material properties, locating buried structures and utility lines.
GPR detects variations in dielectric properties in the subsurface which can be very effective for locating non-conductive utilities. This state of the art method is also good for providing subsurface mapping for unknown and abandoned areas.