Mise-a-la-masse-based induced-polarization method for heavy-metal pollution leakage monitoring: Methodology and modeling results

Abstract

A new mise-a-la-masse (MALM)-based induced-polarization (IP) method is developed for heavy-metal contamination monitoring, in which the charged source in a nonperfect conductor and contact measurements are leveraged to achieve higher accuracy. The MALM-based source enhances the amplitude of potential anomalies due to the bottlenecks of weak signal and limited measurement environment which commonly occur in traditional IP methods for heavy-metal contamination monitoring. The charged current intensity inside the conductor is calculated using an approximate formula rather than only following a current source applied in conventional MALM method. Then, the numerical modeling is based on the discreted charged sources and staggered tetrahedral meshes under the finite-element framework. An improved resistivity computation algorithm is developed for the MALM-IP measurements. It is concluded that the numerical results for the proposed technique are consistent with the model parameter variations. Moreover, a soil box experiment is consistent with the modeling results and confirms the viability of the proposed MALM-IP method. The verification of this technology also is based on the comparisons of numerical modeling and soil box experiment results with those of traditional IP methods and indicates the superiority of this MALM-IP method for heavy-metal contamination monitoring.