Impact of Vibration and Moisture Content to Light Non-aqueous Phase Liquid Migration in Double-Porosity Media

Abstract

Disaster such as earthquake has an impact to water resources particularly groundwater. The migration of pollutant in groundwater is crucial particularly due to earthquake impact. In addition, the soil moisture content also might influence the pollutant migration. Therefore, this paper presents the investigation of light non-aqueous phase liquid (LNAPL) migration in laterite soil with two dissimilar moisture contents with and without vibration. The study of LNAPL migration was investigated using digital image analysis. The lab-scale experiments were conducted by using soil column, mirror, LNAPL and Nikon D90 digital camera. Unsaturated laterite soil was poured in the acrylic column then compressed until 100 mm height. Then, LNAPL was poured onto the soil column surface instantaneously. The pattern and behavior of LNAPL migration in laterite soil was monitored and recorded using digital image processing technique (DIPT) at certain time intervals. The images were processed with Surfer software and Matlab routine inorder to plot the LNAPL migration pattern using hue-saturation-intensity (HSI) value. The study found that higher rate migration of LNAPL with high moisture content, and the rate of LNAPL migration decreases with presence of vibration and with lower moisture content. The migration time required to reach bottom of soil was longer for low moisture content with/without vibration as compared to the high moisture content with/without vibration.