Phosphogypsum, as an industrial solid waste, can lead to environmental pollution through the infiltration of its leachate into the groundwater system via subsurface flow pathways. Consequently, during the construction of phosphogypsum stacks, a detailed investigation of potential leakage pathways in the subsurface and surrounding areas is imperative. However, the traditional deployment of three-dimensional high-density electrical resistivity observation systems laid challenges.
Moreover, conventional resistivity data collection using standard instruments is time-consuming, particularly in realistically complex geological conditions, making it challenging to apply. Focusing on a specific phosphogypsum stacking site, this work integrates practical geological considerations and employs parallel electrical resistivity methods for data acquisition, obtaining a three-dimensional dataset within the observed area. Subsequently, three-dimensional electrical resistivity inversion imaging, incorporating topographic information, is employed for subsurface interpretation of the stacking site. A total of five anomalous zones were identified during the field survey, aligning with geological information revealed through borehole drilling.
Based on the 3D (three-dimensional) electrical resistivity inversion results and in conjunction with the actual geological conditions on-site, the resistivity values within the surveyed area were delineated. The overburden and water-bearing fracture zones exhibit lower resistivity, measuring less than 300 Ω·m. The moderately weathered limestone displays resistivity values ranging from 300 Ω·m to 1500 Ω·m, while the resistivity of intact limestone, fractured limestone, and overlying gravelly soil all surpasses 1500 Ω·m. This comprehensive investigation provides accurate guidance for the subsequent construction of impermeable curtains, aiming to prevent further environmental contamination.

Parallel electrical method , 3D electrical resistivity inversion , Pollution prevention, Geological anomaly, Geological survey