Application of Electrical Properties in Monitoring the Performance of Containment Barrier

Containment barriers are vertical walls that are able to prevent the migration of subsurface contaminants by impeding the groundwater flow. Although containment barriers have been used for decades and methodology are readily available, proper mix of barrier materials to contain specific contaminants requires significant experience in the field. Therefore, verifying the barrier permeability during construction and monitoring the leakage of containment barriers after the construction are essential for barrier application. The objective of this study is to investigate whether the electrical resistivity of soil-bentonite mixture can be used to prospect its permeability. The electrical resistivity of weathered granite soils were measured under varying bentonite content. In addition, permeability tests were performed to investigate the relationship between bentonite content and hydraulic conductivity. As a result, correlations between the bulk electrical resistivity and the bentonite content of soil-bentonite mixtures were derived. Based on the experimental data, it was concluded that the electrical resistivity has a potential in estimating both bentonite content and hydraulic conductivity of soil-bentonite mixtures.