An Integrated Geophysical Investigation Of An Inactive Wood Treatment Facility

Five geophysical methods were used to characterize the subsurface at an inactive wood treatment facility. Seismic refraction,<br>electromagnetic conductivity (EM-3 1 and EM-34), very low frequency (VLF), and spontaneous potential (SP) methods were used to<br>locate potential water-bearing zones and to help understand the driving mechanisms for the movement of groundwater and chemical<br>constituents below the site. The investigation was successful in delineating areas where gravity drainage, groundwater seepage, and<br>preferential groundwater movement was occurring. Typically, these areas were characterized by lower bedrock elevations, decreased<br>bedrock velocities, increased electrical conductivity values, and anomalous VLF and SP deflections. The data were incorporated into<br>the generation of site models, the determination of critical geologic information, and the placement of seven proposed monitoring<br>wells.