Field Demonstration of Successful Bioaugmentation To Achieve Dechlorination of Tetrachloroethene To Ethene
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- 作者：David W. Major ; Michaye L. McMaster ; Evan E. Cox ; Elizabeth A. Edwards ; Sandra M. Dworatzek ; Edwin R. Hendrickson ; Mark G. Starr ; Jo Ann Payne ; and Lois W. Buonamici
- 刊名：Environmental Science & Technology
- 出版年：2002
- 出版时间：December 1, 2002
- 年：2002
- 卷：36
- 期：23
- 页码：5106 - 5116
- 全文大小：246K
- 年卷期：v.36,no.23(December 1, 2002)
- ISSN：1520-5851
文摘
A laboratory microcosm study and a pilot scale field testwere conducted to evaluate biostimulation and bioaugmentation to dechlorinate tetrachloroethene (PCE) to etheneat Kelly Air Force Base. The site groundwater containedabout 1 mg/L of PCE and lower amounts of trichloroethene(TCE) and cis-1,2-dichloroethene (cDCE). Laboratorymicrocosms inoculated with soil and groundwater fromthe site exhibited partial dechlorination of TCE to cDCE whenamended with lactate or methanol. Following the additionof a dechlorinating enrichment culture, KB-1, thechlorinated ethenes in the microcosms were completelyconverted to ethene. The KB-1 culture is a naturaldechlorinating microbial consortium that contains phylogenetic relatives of Dehalococcoides ethenogenes. Theability of KB-1 to stimulate biodegradation of chlorinatedethenes in situ was explored using a closed loop recirculationcell with a pore volume of approximately 64 000 L. Thepilot test area (PTA) groundwater was first amended withmethanol and acetate to establish reducing conditions.Under these conditions, dechlorination of PCE to cDCE wasobserved. Thirteen liters of the KB-1 culture were theninjected into the subsurface. Within 200 days, theconcentrations of PCE, TCE, and cis-1,2-DCE within thePTA were all below 5 
g/L, and ethene production accountedfor the observed mass loss. The maximum rates ofdechlorination estimated from field data were rapid (half-lives of a few hours). Throughout the pilot test period,groundwater samples were assayed for the presence ofDehalococcoides using both a Dehalococcoides-specific PCRassay and 16S rDNA sequence information. The sequencesdetected in the PTA after bioaugmentation were specificto the Dehalococcoides species in the KB-1 culture.These sequences were observed to progressively increasein abundance and spread downgradient within the PTA.These results confirm that organisms in the KB-1 culturepopulated the PTA aquifer and contributed to the stimulationof dechlorination beyond cDCE to ethene.
g/L, and ethene production accountedfor the observed mass loss. The maximum rates ofdechlorination estimated from field data were rapid (half-lives of a few hours). Throughout the pilot test period,groundwater samples were assayed for the presence ofDehalococcoides using both a Dehalococcoides-specific PCRassay and 16S rDNA sequence information. The sequencesdetected in the PTA after bioaugmentation were specificto the Dehalococcoides species in the KB-1 culture.These sequences were observed to progressively increasein abundance and spread downgradient within the PTA.These results confirm that organisms in the KB-1 culturepopulated the PTA aquifer and contributed to the stimulationof dechlorination beyond cDCE to ethene.