Influence of diesel fuel contamination on the electrical properties of unsaturated soil at a low frequency range of 100 Hz-10 MHz

In this study, the effect of diesel fuel contamination on the electrical properties of unsaturated soils was estimated in the low frequency ranges. For the soils having 5% water content, the electrical resistivity increased with the diesel fuel contents while the permittivity decreased at higher diesel contents. However, at 15% water content, the variation of electrical properties was not significant possibly because most of the electric currents should occur through the pore water. The linear relationship between the electrical resistivity and the diesel fuel contents in soil was developed at 5% water content, which implied that the electrical resistivity could be used to quantify the extent of diesel fuel contamination in soil. The results indicated that the electrical properties including the resistivity and the permittivity could give the reliable estimation on the diesel contamination with the low water content in soil and the frequency applied below 1 MHz.