Enviroprobe recently conducted soil resistivity testing with Wenner Array 4-point Method at several sites in central and north New Jersey. This method is the most commonly used test method to measure the resistivity of soil for electrical grounding design. The Wenner array consists of a line of four equally spaced electrodes. Current is injected through the outer electrodes and potential is measured between the inner electrodes. The testing utilized an Advanced Geoscience Inc. (AGI) SuperSting R8 resistivity system and was done in a perpendicular pair at each testing location using the standard traverse setup with the maximum “a” spacing as 100'. For accurate results, testing locations should be far away from fences, underground utilities and other electrically conductive objects. All field services were conducted in compliance with the industry standard of guidelines found in ASTM G57-06 and IEEE Std 81.