Remediation of trichloroethylene in an artificial aquifer with trees: A controlled field study

Poplar trees have been evaluated in the field for the control of contaminat ed groundwater movement, but to date, the fate of the contaminants has not been demonstrated. In the present study, we tested a hybrid poplar for the uptake and degradation of trichloroethylene (TCE). Plants were exposed to T CE-contaminated groundwater under field conditions in lined cells for three years. During the growing seasons, the trees were able to remove over 99% of the added TCE. Less than 9% of the TCE was transpired to the atmosphere during the second and third years, and examination of the tissue showed exp ected metabolites, but at low levels. Chloride did not significantly accumu late in the plant tissues, but chloride ion increased in the soil in amount s that approximately corresponded to TCE loss. These results demonstrate th at treatment of TCE-contaminated groundwater with this poplar clone can res ult in efficient destruction of TCE.