Effect of salt and NAPL on electrical resistivity of fine-grained soil-sand mixtures

Electrical resistivity of soils are very important for various engineering projects, for example, subsurface transmission of either heated fluids or high-voltage buried power cables; storage and contamination of radioactive waste. Electrical resistivity mainly depends on the type of soil and its water content or saturation. The present study measures the electrical resistivity of commercially available kaolinite clay mixed with various percentages of sand & tried to establish a relationship between electrical resistivity and water content of the soil mixtures. Also, electrical resistivity has been measured with the addition of salts and non-aqueous phase liquid (NAPL) contamination into the kaolinite and/or kaolinite-sand mixture. The results show that electrical resistivity reduced drastically with the addition of salt but the resistivity increases with the addition of NAPL for kaolinite and kaolinite-sand mixtures.