Clay soils have lower resistivity due to charged double-layers and typically higher moisture contents than coarser soils. Soil water carries the majority of the current flow, since typical soil grains such as quartz have high resistivity. The content of charged ions in the soil pore water affects the electron flow. NAPLs may behave as electrical insulators when compared to water. Resistivity of both the water and the solids drops when temperature increases.
Resistivity increases with air saturation.
Some of these properties must change sufficiently for ERT imaging to detect it. In addition, ERT has proved to be effective in site characterization, ground water and mineral exploration. Mapping contaminant plumes Cavity detection Sinkhole detection Mapping bedrock topography Locating leakage through dams Archeological site characterization Mineral exploration Groundwater exploration ERT Services Offered By SteamTech Environmental Services SteamTech has experience in full-scale applications of ERT to thermally enhanced remediation sites in Visalia, southern California and Portsmouth, Ohio. SteamTech is constantly researching and developing the technology in-house at the leading edge.