Cross borehole induced polarization to detect subsurface NAPL at the Savannah River Site, South Carolina

Abstract

Spectral induced polarization measurements were acquired in six cross-borehole panels within four boreholes at the Savannah River Site. The investigation was performed to delineate the presence of dense non-aqueous phase liquids (DNAPL) which were periodically released from the 1950's through the 1980's at the A-14. Measurements were made at 1/4 and 1/16 Hertz and the first four odd harmonics. Data inversion for model parameters was performed with the use of proprietary Earth Resources Laboratory inversion codes. Results indicate the possible presence of three main zones of contamination within the region of our wells. Based on the geophysical results, suggestions have been made regarding the location of three wells to be used for ground truthing.