Je. Mccray et Ml. Brusseau, CYCLODEXTRIN-ENHANCED IN-SITU FLUSHING OF MULTIPLE-COMPONENT IMMISCIBLE ORGANIC LIQUID CONTAMINATION AT THE FIELD-SCALE - MASS REMOVAL EFFECTIVENESS, Environmental science & technology, 32(9), 1998, pp. 1285-1293
The feasibility of ''enhanced-solubility'' remediation technologies, d
esigned to enhance the removal of nonaqueous-phase organic liquids (NA
PLs) from the subsurface, must be tested at the field scale. Herein ar
e reported the results of an experiment designed to evaluate the effec
tiveness of a cyclodextrin(sugar) solution for enhanced-solubilization
removal of a multicomponent NAPL from an aquifer. This effort is the
first field test of this innovative technology, termed a ''complexing
sugar flush'' (CSF). The saturated zone within an enclosed cell was fl
ushed with 8 pore volumes of a 10 wt % cyclodextrin solution. The cycl
odextrin solution increased the aqueous concentrations of all the targ
et contaminants to values from about 100 to more than 20 000 times the
concentrations obtained during a water flush conducted immediately pr
ior to the CSF. The degree of solubility enhancement was greater for t
he more-hydrophobic contaminants. Conversely, the relative mass remova
l was greater for the less-hydrophobic compounds due to their generall
y higher apparent solubilities, which effected a significant reduction
in the initial mass during the relatively short experiment. The avera
ge reduction in soil-phase concentrations for the target contaminants
was 41%. This mass-removal percentage corresponds well to the results-
of partitioning-tracer tests, which indicated a 44% reduction in the a
verage NAPL saturation.