Abstract: The remediation of heavy metal contamination in aquifers requires cost-effective dynamic monitoring methods as support. However, traditional monitoring methods have issues such as being time-consuming, costly, producing delayed data, and causing significant disturbances to the site. This paper uses copper ions as an example and employs Electrical Resistivity  Tomography (ERT)，a method offering rapid, low-cost, real-time dynamic monitoring with in-situ, non-invasive advantages. Through one-dimensional and two-dimensional sandbox experiments, the feasibility of using ERT to monitor heavy metal contamination in aquifers and the process of in-situ chemical remediation is validated, while factors affecting monitoring accuracy are also explored. The study results show that in the one-dimensional sand column experiment, the correlation coefficient (R²) between ERT monitoring data and sampling data exceeds 0.96 during the contamination phase, with a relative error (δ) below 4.04%; during the remediation phase, R² exceeds 0.94, and δ is below 6.43%. In the two-dimensional sandbox experiment, a quantitative analysis of ERT monitoring results was conducted using the spatial moment method of the contaminant plume combined with sampling data. The first moment error of copper ion migration is below 9%, and the second moment error is below 14% during the contamination phase; during the remediation phase, the first moment error is below 11%, and the second moment error is below 19%. Furthermore, the accuracy of information capture by the ERT device is influenced by the migration and reaction rates of copper ions. The slower the migration and reaction rates of copper ions, the higher the accuracy of information capture by the ERT device. This study validates the feasibility and accuracy of the ERT method in monitoring heavy metal contamination and the remediation process in groundwater, providing important data support for practical applications.

Key words: Electrical Resistivity Tomography(ERT), groundwater contamination, copper ions, contamination remediation;
aqueous medium