Detecting oil contamination by Ground Penetrating Radar around an oil storage facility in Dhanbad, Jharkhand, India

the subsoil and groundwater were suspected to be polluted by leakage from underground tanks around the oil storage facility in Dhanbad, Jharkhand, India. to delineate the seepage zone, integrated geophysical methods comprising Ground Penetrating Radar (GPR) and 2D electrical Resistivity Imaging (eRI) methods were employed over the suspected zone and in the close vicinity. the studies were conducted over eight underground storage tanks containing petrol and kerosene. GPR system with antennas operating at frequencies of 250 MHz and 800 MHz were deployed. the GPR survey delineated a hydrocarbon contaminated soil and/or groundwater zone as deciphered from the amplitude shadow zones within 0.71.0 m depth from the surface. Limited electrical Resistivity Imaging (eRI) study was conducted over one traverse using a 2D multi electrode imaging system employing ‘Wenner-schlumberger’ configuration in the area where GPR anomalies were located. Relatively lower resistivities ranging from 0.5 ohm-m to 9.5 ohm-m were found at the locations where GPR anomalies indicated hydrocarbon seepage. the results from the eRI study revealed a good match with the findings from GPR study.