Migration of hydrocarbon liquid in unsaturated laterite soil with dissimilar volume and moisture content

Abstract

Groundwater contaminations due to hydrocarbon or organic solvent spills in saturated or unsaturated zones affect the water resources. The quantity of hydrocarbon spills in the groundwater might influence the hydrocarbon migration. In addition, the soil moisture content in influencing the rate of migration is also unknown. Therefore, this paper presents the investigation migration of Light Non-Aqueous Phase Liquid (LNAPL) in unsaturated laterite soil with two dissimilar moisture contents and different of LNAPL volume. These lab-scale studies discuss the results of migration phenomena by employing image analysis by using soil column, mirror, LNAPL, and Nikon D90 digital camera. Aggregated soil was poured and compressed in an acrylic column until 100 mm height. Then LNAPL was poured onto the soil column surface instantaneously. The LNAPL migration pattern in laterite soil was monitored and recorded using digital image processing technique (DIPT) at certain time intervals then were processed with Surfer software and Matlab routine for plotting the LNAPL migration pattern. As a result, the analysis displayed the higher rate migration of LNAPL with high moisture content and bigger amount of LNAPL volume. However, the rates of LNAPL migration decrease with lower moisture content and small amount of LNAPL volume. The migration time required to reach bottom of soil was longer for low moisture content with smaller amount of LNAPL volume as compared to the high moisture content with bigger amount of LNAPL volume.