Application of ERT and VLF-EM Methods for Mapping Leachate Pollution from Agro-Processing Waste in Oghara, South-South Nigeria

Authors

Keywords:

Electrical Resistivity Tomography, VLF-EM, leachate pollution, palm kernel waste

Abstract

The study employed Electrical Resistivity Tomography (ERT) and Very Low Frequency Electromagnetic (VLF-EM) geophysical techniques coupled with hydrochemical analysis to identify leachate pollution from palm kernel wastes in Oghara, South-South Nigeria. The indiscriminate disposal of organic wastes generated conductive leachate solution that contaminated shallow groundwater in the study area. The ERT was carried out along five traverses, and the results revealed very low resistivity values (20.3-95 Ωm) at depths of 2-15 m. The VLF-EM data were processed using Fraser and Karous-Hjelt filters, and shallow conductive plumes (35-65 mS/m) were detected at depths of less than 15 m. The hydrochemical analysis of groundwater samples collected from up and down gradient directions (n = 10) showed an increase in total dissolved solids (1,240-3,850 mg/L), electrical conductivity (2,480-6,200 μS/cm), ammonium (4.2-18.6 mg/L), and total coliforms in the down gradient direction exceeding the NSDWQ and WHO standards for potable water. The correlation of geophysical and hydrochemical results revealed the presence of leachate plumes with high concentrations of organic acids and dissolved ions that infiltrated the shallow aquifer in the study area. The study established the extent of pollution and the risk posed to the shallow groundwater in Oghara, Nigeria, and provides baseline data for similar studies in palm oil processing industries

Author Biography

Jerry Osadebamwen Osifo

Department of Physics

Dimensions

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Published

2026-08-21

How to Cite

Osifo, J. O., & Ogumeyo, A. (2026). Application of ERT and VLF-EM Methods for Mapping Leachate Pollution from Agro-Processing Waste in Oghara, South-South Nigeria. Nigerian Journal of Physics, 35(S), 46-56. https://doi.org/10.62292/njp.v35(s).2026.657

Issue

Vol. 35 No. S (2026): Nigerian Journal of Physics - Vol. 35(S)

Section

Articles
Copyright & Licensing

Copyright (c) 2026 Jerry Osadebamwen Osifo, Ajirioghene Ogumeyo

Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

How to Cite

Osifo, J. O., & Ogumeyo, A. (2026). Application of ERT and VLF-EM Methods for Mapping Leachate Pollution from Agro-Processing Waste in Oghara, South-South Nigeria. Nigerian Journal of Physics, 35(S), 46-56. https://doi.org/10.62292/njp.v35(s).2026.657