a method of land surveying that electronically registers together multi - layer underground and surface images of a surface volume with buried utilities and other infrastructures . such method further comprises assembling and presenting the combination to a device in the field that visually guides crews in their safe digging of the ground nearby . the orienting , scaling , and registering of a first image layer is to a standardized orientation and scaling on a map of a photograph of a land surface from a zenith point in space above . then the orienting , scaling , and registering of a second image layer is made to the standardized orientation and scaling on the map . this layer is a result of a ground penetrating radar investigation of buried objects point - by - point in an immediate search area of a corresponding ground surface . underground buried objects and utilities are thereby located to make safe digging nearby .