Field test of cyclodextrin for enhanced in-situ flushing of multiple-component immiscible organic liquid contamination: Project overview and initial results

The purpose of this paper is to present an overview and the initial results of a pilot-scale experiment designed to test the use of cyclodextrin for enhanced in-situ flushing of an aquifer contaminated by immiscible liquid. This is the first field test of this technology, termed a complexing sugar flush (CSF). The field test was conducted within a solvent and fuel disposal site at Hill Air Force Base, UT. The cyclodextrin solution increased the aqueous concentrations of all the target contaminants to values from about 100 to more than 20000 times the concentrations obtained during the water flush conducted prior to the CSF. Concomitantly, the CSF greatly enhanced the rate of mass removal during the 8 pore-volume flush, which resulted in a 41% reduction in contaminant mass. Based on these results, it is clear that the CSF technology was successful in enhancing the remediation of the immiscible-liquid contaminated site. There are several attributes of cyclodextrin that in some situations may offer advantages compared to using surfactants or cosolvents for solubilization-based enhanced flushing.