Time Domain Induced Polarization Data Acquisition at Contaminated Sites

Time domain induced polarization (TDIP) has emerged as a highly effective tool for characterizing soil and groundwater contamination. Numerous studies have focused on the objective of enhancing accuracy of TDIP results. However, the acquisition of high quality TDIP data has received less attention than it deserved. In this study, three data acquisition methods were evaluated across seven distinct sites, with a particular focus on the controlling factors that influence data quality. This study addresses the questions about how to select a reliable TDIP acquisition method. The results demonstrate that there are significant differences in the raw data obtained through different acquisition methods, with the inverted results derived from these datasets exhibiting varying discrepancy. The data quality associated with the dual cables utilizing non-polarizable electrodes layout (Dual-CL-NP) is markedly superior, thereby ensuring the reliability of the results. Furthermore, apparent resistivity and measured voltage are identified as the key factors on data quality. The threshold values for selecting the acquisition method are determined. The Dual-CL-NP method should be utilized when the averaged apparent resistivity is less than 7.9 Ω•m. Consequently, a guideline for TDIP data acquisition is proposed, which addresses the limitations associated with TDIP data quality and facilitates its advancement