DNAPL Detection and Monitoring Using Electrical Resistive Tomography – A Case Study in North Italy, Rho-Milan

The study deals with the detection and monitoring of DNAPL using electric resistive tomography (ERT) on the topographic surface and in boreholes. The surveys were performed in an industrial area that had been contaminated by chlorinated solvents; the site, at Rho in north Italy, lies about 10 km NW of Milan. The ERT data, acquired on the topographic surface and in the boreholes, reveal a scenario of distributed resistivity variations in an area that was once associated with the movement of contaminants over the ground. The geophysical data interpretation was constrained by sedimentary stratigraphy, revealed by boreholes drilled in the area. The results validate the use of electrical resistive tomography for the detection and monitoring of DNAPL.