Application of 2D electrical resistivity imaging for monitoring subsurface contaminant plumes at Challawa Industrial Estate

Abstract

Geoelectrical methods provide valuable tools for detecting and monitoring subsurface contamination. This study applied two-dimensional (2D) electrical resistivity imaging (ERI) using Wenner array configurations across four profiles in the vicinity of the Challawa Industrial Estate, Kano State, Nigeria. Field data were acquired at electrode spacing of 5 to 25 m, and inverted using RES2DINV and ZONDRES2D software packages. The resistivity models delineated five main subsurface layers: topsoil, laterite, weathered basement, fractured basement, and fresh basement. Zones of anomalously low resistivity (< 350 Ωm) corresponded to contaminant plumes derived from tannery and textile effluents. Results correlated strongly with borehole lithological logs and physico-chemical water analysis, confirming the reliability of ERI for monitoring contamination. The study demonstrates that electrical resistivity imaging provides an efficient, cost-effective method for delineating subsurface pollution and informing groundwater management strategies in industrial environments.