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Title: Uranium Removal from Groundwater via In Situ Biostimulation: Field-Scale Modeling of Transport and Biological Processes

Abstract

During 2002 and 2003, bioremediation experiments in the unconfined aquifer of the Old Rifle UMTRA field site in western Colorado provided evidence for the immobilization of hexavalent uranium in groundwater by iron-reducing Geobacter sp. stimulated by acetate amendment. As the bioavailable Fe(III) terminal electron acceptor was depleted in the zone just downgradient of the acetate injection gallery, sulfate-reducing organisms came to dominate the microbial community. In the present study, we use multicomponent reactive transport modeling to analyze data from the 2002 field experiment to 1) identify the dominant transport and biological processes controlling uranium mobility during biostimulation, 2) determine field-scale parameters for these modeled processes, and 3) apply the calibrated process models to history match observations during the 2003 field experiment. In spite of temporally and spatially variable observations during the field-scale biostimulation experiments, the coupled process simulation approach was able to establish a quantitative characterization of the principal flow, transport, and reaction processes that could be applied without modification to describe the 2003 field experiment. Insights gained from this analysis include field-scale estimates of bioavailable Fe(III) mineral, and the magnitude of uranium bioreduction during biostimulated growth of the iron-reducing and sulfate-reducing microorganisms.

Authors:
; ; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
918462
Report Number(s):
PNNL-SA-50626
Journal ID: ISSN 0169-7722; JCOHE6; 3573; KP1302000; TRN: US0805828
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Contaminant Hydrology, 93(2007):216-235; Journal Volume: 93
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; ACETATES; AQUIFERS; BIOREMEDIATION; ELECTRONS; MICROORGANISMS; MODIFICATIONS; REMOVAL; SIMULATION; TRANSPORT; URANIUM; bioremediation, biogeochemistry, reactive transport modeling, uranium; Environmental Molecular Sciences Laboratory

Citation Formats

Yabusaki, Steven B., Fang, Yilin, Long, Philip E., Resch, Charles T., Peacock, Aaron D., Komlos, John, Jaffe, Peter R., Morrison, Stan J., Dayvault, Richard, White, David C., and Anderson, Robert T. Uranium Removal from Groundwater via In Situ Biostimulation: Field-Scale Modeling of Transport and Biological Processes. United States: N. p., 2007. Web. doi:10.1016/j.jconhyd.2007.02.005.
Yabusaki, Steven B., Fang, Yilin, Long, Philip E., Resch, Charles T., Peacock, Aaron D., Komlos, John, Jaffe, Peter R., Morrison, Stan J., Dayvault, Richard, White, David C., & Anderson, Robert T. Uranium Removal from Groundwater via In Situ Biostimulation: Field-Scale Modeling of Transport and Biological Processes. United States. doi:10.1016/j.jconhyd.2007.02.005.
Yabusaki, Steven B., Fang, Yilin, Long, Philip E., Resch, Charles T., Peacock, Aaron D., Komlos, John, Jaffe, Peter R., Morrison, Stan J., Dayvault, Richard, White, David C., and Anderson, Robert T. Mon . "Uranium Removal from Groundwater via In Situ Biostimulation: Field-Scale Modeling of Transport and Biological Processes". United States. doi:10.1016/j.jconhyd.2007.02.005.
@article{osti_918462,
title = {Uranium Removal from Groundwater via In Situ Biostimulation: Field-Scale Modeling of Transport and Biological Processes},
author = {Yabusaki, Steven B. and Fang, Yilin and Long, Philip E. and Resch, Charles T. and Peacock, Aaron D. and Komlos, John and Jaffe, Peter R. and Morrison, Stan J. and Dayvault, Richard and White, David C. and Anderson, Robert T.},
abstractNote = {During 2002 and 2003, bioremediation experiments in the unconfined aquifer of the Old Rifle UMTRA field site in western Colorado provided evidence for the immobilization of hexavalent uranium in groundwater by iron-reducing Geobacter sp. stimulated by acetate amendment. As the bioavailable Fe(III) terminal electron acceptor was depleted in the zone just downgradient of the acetate injection gallery, sulfate-reducing organisms came to dominate the microbial community. In the present study, we use multicomponent reactive transport modeling to analyze data from the 2002 field experiment to 1) identify the dominant transport and biological processes controlling uranium mobility during biostimulation, 2) determine field-scale parameters for these modeled processes, and 3) apply the calibrated process models to history match observations during the 2003 field experiment. In spite of temporally and spatially variable observations during the field-scale biostimulation experiments, the coupled process simulation approach was able to establish a quantitative characterization of the principal flow, transport, and reaction processes that could be applied without modification to describe the 2003 field experiment. Insights gained from this analysis include field-scale estimates of bioavailable Fe(III) mineral, and the magnitude of uranium bioreduction during biostimulated growth of the iron-reducing and sulfate-reducing microorganisms.},
doi = {10.1016/j.jconhyd.2007.02.005},
journal = {Journal of Contaminant Hydrology, 93(2007):216-235},
number = ,
volume = 93,
place = {United States},
year = {Mon Mar 12 00:00:00 EDT 2007},
month = {Mon Mar 12 00:00:00 EDT 2007}
}
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