EVALUATION OF FLOW RATE IN UNSATURATED ROCK: FIELD TEST WITH INTEGRATED APPROACH

The knowledge of the unsaturated flow rate is essential for both groundwater protection and management, however it is not easy to determine experimentally, especially on the rocks and in the field. This study aims to evaluate the flow rate of potential contaminants in a porous aquifer using an integrated approach that combines electrical resistivity measurements with a large ring infiltrometer test. Specifically, the field tests were carried out on the outcrop of sandstone in a quarry, located in Southern Italy, which has recently been affected by mycelium sludge derived from pharmaceutical industry waste. The electrical resistivity tomography was carried out to visualise the infiltration of water in the subsoil in order to evaluate the unsaturated water flow in the sandstone. Simultaneously, the vertical flow into the unsaturated subsoil was investigated by measuring water levels in a large adjustable ring infiltrometer, sealed directly on the rock. The results of this study confirm the efficacy of the combined methodologies to monitor the vertical flow through unsaturated porous rock.