Geophysical surveying involves the non-invasive investigation of subsurface conditions in the Earth through measuring, analyzing and interpreting physical fields from the ground surface for the purpose of characterizing soils, geology, geological structure, groundwater, contamination, and human artifacts beneath the Earth's surface. Geophysical surveying is often helpful in the initial stages of projects involving; infrastructure development such as highways, bridges and other general development; groundwater exploration and contamintion mapping; geologic hazards such as sinkholes and faults; environmental hazards such as landfills, buried tanks and drums; as well as, the location of utilities, archeological sites and forensics.