Investigating solute transport and reaction using a mechanistically coupled geochemical and geophysical modeling approach

Abstract

The use of geoelectrical monitoring of groundwater quality and contamination is a growing and promising topic. Nowadays, geoelectrical methods are mostly used as qualitative detection tools. This study aims to better use geoelectrical signals as a complementary tool for the quantitative characterization of chemical species transport and reaction in the porous matrix by developing a coupled mechanistic model. We examine the dissolution of calcite as an effective proof-of-concept. Our investigation focuses on the impact of the reactive zone’s position, extent, and intensity of geoelectrical signals under various inlet conditions. We conducted five experiments on flow-through columns equipped with geoelectrical monitoring. This study presents a unique dataset that is analyzed using a workflow that combines reactive transport numerical simulation with numerical modeling of geoelectrical and structural properties. The comparison of the predicted signals with the experimental data clearly shows the characterization of the spatial and temporal distributions of the reaction rates.