A mass balance study of the phytoremediation of perchloroethylene-contaminated groundwater.
A mass balance study was performed under controlled field conditions to investigate the phytoremediation of perchloroethylene (PCE) by hybrid poplar trees. Water containing 7-14 mg L(-1) PCE was added to the test bed. Perchloroethylene, trichloroethylene, and cis-dichloroethylene were detected in the effluent at an average of 0.12 mg L(-1), 3.9 mg L(-1), and 1.9 mg L(-1), respectively. The total mass of chlorinated ethenes in the water was reduced by 99%. Over 95% of the recovered chlorine was as free chloride in the soil, indicating near-complete dehalogenation of the PCE. Transpiration, volatilization, and accumulation in the trees were all found to be minor loss mechanisms. In contrast, 98% of PCE applied to an unplanted soil chamber was recovered as PCE in the effluent water or volatilized into the air. These results suggest that phytoremediation can be an effective method for treating PCE-contaminated groundwater in field applications.
University of Washington, Department of Civil and Environmental Engineering, Seattle, WA 98195, USA.
C Andrew
CA
James
Gang
G
Xin
Sharon L
SL
Doty
Indulis
I
Muiznieks
Lee
L
Newman
Stuart E
SE
Strand
D001673:Biodegradation, Environmental; D002712:Chlorides / Q000032:analysis; D004784:Environmental Monitoring; D060587:Groundwater / Q000737:chemistry*; D032107:Populus / Q000378:metabolism; D012987:Soil / Q000737:chemistry; D013750:Tetrachloroethylene / Q000032:analysis* / Q000378:metabolism; D055549:Volatile Organic Compounds / Q000032:analysis / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000378:metabolism
D002712:Chlorides; D012987:Soil; D055549:Volatile Organic Compounds; D014874:Water Pollutants, Chemical; D013750:Tetrachloroethylene