Geophysical Method of Investigating Groundwater and Sub-Soil Contamination – A Case Study

Abstract

Geophysical methods can be helpful in mapping areas of contaminated soil and groundwater. Electrical resistivity surveys were carried out at a site of shallow hydrocarbon contamination in Ahoada, South-South Nigeria. This was aimed at evaluating the subsoil conditions and groundwater quality of the area three years after the post-spill clean-up exercise. The geophysical investigation involved the Vertical Electrical Sounding (VES) technique using the Schlumberger configuration and the horizontal profiling method. The data from the two different approaches correlate well, and the generated profiles of the acquired data helped to map the contaminant plume, which was delineated as an area of high interpreted resistivities. The VES result shows that the subsurface layers up to a depth of 49 m is of moderate to high resistivity values (>200 Ώm) that may affect crops and groundwater development in the study area. However good aquifer can still be obtained from the depth of 30 m and above.

Reconnaissance of Groundwater Quality Impact

“…Groundwater is increasingly vulnerable in regions with low mean annual rainfall, prone to drought and where groundwater is mined. This is particularly true Typically oil spills are known to impact surface water quality, however, a geophysical investigations based on groundwater electric resistivity survey conducted three years after the oils spill resulting from rupture of pipeline in the region of Ahoada (South Nigeria) showed that groundwater still contained hydrocarbons (Nwankwo and Emujakporue, 2012). Increased vulnerability to groundwater resources due to exploitation of shale gas in the Appalachian Basin is documented by Warner et al(2012).…”

Geophysical Survey on Open Dumping Landfill for Monitoring Spread of Leachate: A Case Study in Pekanbaru, Riau, Indonesia

“…Electrical Resistivity Imaging (ERI) is the most common and successfully used especially in groundwater exploration and environmental problem like soil or groundwater contamination (Azhar et al, 2016;Hamzah et al, 2007Hamzah et al, , 2008Jumary et al, 2002;Saad et al, 2012;Adi Suryadi et al, 2019) .By using ERI, resistivity distribution of subsurface will be imensional image. The model that resulted is showing the apparent resistivity value which can be interpreted as contaminant depend on Akankpo, 2011;N. Nwankwo and O. Emujakporue, 2012;Okereke and Harcourt, 2012;Surface et al, 2011;.…”

Mapping of hydrocarbon‐ and scrap‐metal‐contaminated soil using volatile organic compounds and electromagnetic profiling methods

“…Electrical and electromagnetic (EM) methods are frequently used to study soil and groundwater contamination caused by different types of waste (Kaya, Özürlan and Şengül 2007;Nwankwo and Emujakporue 2012;Żogała et al 2012;Belmonte-Jiménez et al 2014). Specifically, electrical resistivity tomography and EM profiling (EMP) are effective methods for the characterisation of hydrocarbon-contaminated sites (Delgado-Rodríguez et al 2006a,b;Rosales et al 2012;Adelusi, Akinlalu and Adebayo 2013;Delgado-Rodríguez et al 2014;Koroma, Arato and Godio 2015).…”