Complex resistivity dispersion for monitoring soil contaminated by selected organic pollutants

With the rapid development of the global petrochemical industry and the widespread use of organic solvents, the problem of non-aqueous phase pollution of soil is becoming increasingly serious. Due to the significant differences in complex resistivity among various pollutants, studying the complex resistivity dispersion characteristics of different pollution types and degrees can help evaluate contaminated sites and is highly significant for pollution control. In this study, soil samples with different concentrations of trichloroethylene, xylene and gasoline were prepared, the complex resistivity dispersion curves of each group were measured, the electrical parameters were obtained by inversion. The effectiveness of the indoor experiment was verified by the field pollution delineation experiment. The results reveal the strong correlation between the degree of soil organic matter pollution, the type of pollution and the complex resistivity dispersion curve, and clarify the internal relationship between the type of pollution, the degree of pollution and the electrical parameters. Among them, the real part resistivity can effectively reflect the resistivity difference of contaminated soil, and the imaginary part resistivity can distinguish the characteristics of pollution degree and pore water composition. Based on theoretical analysis, sample determination and field test, this paper proves the effectiveness of using complex resistivity dispersion characteristics as an evaluation method for non-aqueous soil pollution, and provides a basis for complex resistivity method in the field of organic pollution monitoring and evaluation.