ABSTRACT
Restoration or cleanup of a contaminated aquifer usually involves also addressing the contaminated soils at the vadose zone. Several techniques are available to treat contaminants in the vadose zone. These techniques include excavation and removal, physical treatments, biological treatments, thermal treatments, and stabilization treatments. Excavation and soil removal is one of the most common activities in groundwater remediation and cleanup. The physical treatments for treating contaminants in the vadose zone include soil—vapor extraction, soil washing, and soil flushing. Slurry biodegradation, ex situ bioremediation and land farming, and in situ biological treatment are biological treatments for treating contaminants in the vadose zone. Thermal treatment is used to treat contaminants in the vadose zone and includes incineration and thermal desorption. Thermal desorption is a physical separation process in which the excavated contaminated soil is heated to a temperature at which the water and organic contaminants are volatilized. The soil stabilization process can be used in either in situ or ex situ treatment.
