Developing a Relation Between Pore Fluid Salinity and Electrical Resistivity of Highly Compacted Bentonite

Highly compacted bentonite is an engineered barrier material that is being examined in the Canadian concept for storage of used fuel bundle in a deep geological repository. Having an estimation of the in situ ground water salinity will help to predict hydro-mechanical behavior of the engineered barriers as well as understanding of any potential corrosion of the cylinders of the used fuel bundles. The current research investigates the impact of pore fluid chemistry on the electrical resistivity of highly compacted bentonite. In these tests, pore fluid solutions were selected to represent groundwater salinity of host rocks locations of the Canadian DGR. Former studies found that electrical resistivity is a powerful tool to monitor the degree of saturation of barrier materials. Following the similar approach, this study suggests that the salinity of the highly compacted bentonite can be monitored by means of electrical resistivity to acquire a clearer picture of the deep geological repository’s performance.