U.S. Department of Energy Office of Biological and Environmental Research

BER Research Highlights


Stimulating Bacteria to Immobilize Chromium in Groundwater
Published: May 15, 2014
Posted: September 22, 2014

Hexavalent chromium is a major contaminant in numerous soil and groundwater systems worldwide, in particular at Department of Energy sites due to former weapons production and reprocessing activities and wastes from electroplating processes, and from industrial efforts to reduce corrosion in steel pipes. Although hexavalent chromium is readily transported in groundwater, reduction to a less mobile form involves the interaction of hexavalent chromium with certain minerals and microorganisms. Specifically, iron-reducing bacteria can convert the oxidized form of iron in clay minerals (ferric iron) into the reduced form of iron (ferrous iron) that can then reduce hexavalent chromium to much less mobile trivalent chromium. Efforts to understand the specific details of this process were recently reported by a team of scientists from Miami University and the Environmental Molecular Sciences Laboratory (EMSL), using EMSL’s ultra-sensitive microscopy and spectroscopy capabilities. Starting with the iron-reducing bacterium Geobacter sulfurreducens and ferric iron-containing clay minerals, the team found that they could provide a specific nutrient to the bacteria that would significantly stimulate the bacteria to reduce ferric to ferrous iron. The resulting ferrous iron was able to reduce hexavalent chromium, and it reduced the chromium even faster as the temperature of the system was increased. In addition to demonstrating a possible way to reduce the transport of hexavalent chromium in groundwater, the team also determined the kinetics of these reactions. These kinetic parameters can now be incorporated into models to improve predictions of the transport of hexavalent chromium in subsurface environments.

Reference: Bishop, M. E., P. Glasser, H. Dong, B. Arey, and L. Kovarik. 2014. “Reduction and Immobilization of Hexavalent Chromium by Microbially Reduced Fe-bearing Clay Minerals,” Geochimica et Cosmochimica Acta 133, 186-203. DOI: 10.1016/j.gca.2014.02.040. (Reference link)

Contact: Paul E. Bayer, SC-23.1, (301) 903-5324
Topic Areas:

  • Research Area: Subsurface Biogeochemical Research
  • Research Area: DOE Environmental Molecular Sciences Laboratory (EMSL)
  • Research Area: Microbes and Communities

Division: SC-23.1 Climate and Environmental Sciences Division, BER

 

BER supports basic research and scientific user facilities to advance DOE missions in energy and environment. More about BER

Recent Highlights

Aug 24, 2019
New Approach for Studying How Microbes Influence Their Environment
A diverse group of scientists suggests a common framework and targeting of known microbial processes [more...]

Aug 08, 2019
Nutrient-Hungry Peatland Microbes Reduce Carbon Loss Under Warmer Conditions
Enzyme production in peatlands reduces carbon lost to respiration under future high temperatures. [more...]

Aug 05, 2019
Amazon Forest Response to CO2 Fertilization Dependent on Plant Phosphorus Acquisition
AmazonFACE Model Intercomparison. The Science Plant growth is dependent on the availabi [more...]

Jul 29, 2019
A Slippery Slope: Soil Carbon Destabilization
Carbon gain or loss depends on the balance between competing biological, chemical, and physical reac [more...]

Jul 15, 2019
Field Evaluation of Gas Analyzers for Measuring Ecosystem Fluxes
How gas analyzer type and correction method impact measured fluxes. The Science A side- [more...]

List all highlights (possible long download time)