Characterizing the effects of iron- and sulfate-reduction on aquifer mineralogy: Linking
geophysics and geomicrobiology
EMSL Project ID
25715
Abstract
This proposal seeks to provide a quantitative understanding of the mineralogical changesaccompanying stimulated iron- and sulfate-reduction during contaminant remediation of uranium
and chromium at two Department of Energy (DOE) field sites, with the goal of linking
geophysical anomalies with changes in geochemistry and microbiology. Our ongoing research in
the area of biogeophysical monitoring has revealed a strong correlation between geophysical
signatures and changes in mineralogical properties; however, much of the detailed
characterization of the microbe-mineral interactions has been limited to laboratory-derived
materials. As our research has expanded to include geophysical monitoring of field-scale
bioremediation activities at two sites of interest to DOE's Environmental Remediation Sciences
Program (ERSP) - Old Rifle, CO and Hanford, WA - we propose to extend our previous
characterization efforts undertaken at the Environmental Molecular Science Laboratory (EMSL)
to focus primarily on field-derived aquifer materials, including phyllosilicates, iron oxides, metal
sulfides, and calcite, and the impact that microorganisms have on creating or altering each.
Introduction
The problem of groundwater contamination by acid-mine drainage, industrial sources,
and government nuclear weapons programs has spawned interest in the ability of microorganisms
to facilitate remediation through sequestration of metals in insoluble precipitates [Drury, 1999;
Ehrlich, 1999; Rittle et al., 1995; Schultze-Lam et al., 1996]. One major barrier to successful
implementation of bioremediation has been the inability to monitor microbial activity and mineral
precipitation at sufficiently high spatial resolution and over large enough areas to understand
where, when and how treatment is occurring [Anderson et al., 2003; Chapelle, 2000]. In
addition, although biostimulation may prove initially effective, it may be difficult to verify
stability of the treatment in the long term [Suzuki et al., 2002].
Project Details
Project type
Large-Scale EMSL Research
Start Date
2007-05-25
End Date
2009-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members
Related Publications
Druhan JL, ME Conrad, KH Williams, AL N'Guessan, PE Long, and SS Hubbard. 2008. "Sulfur Isotopes as Indicators of Amended Bacterial Sulfate Reduction Processes Influencing Field Scale Uranium Bioremediation." Environmental Science & Technology 42(21):7842-7849. doi:10.1021/es800414s