Mineral transformation and biomass accumulation associated with uranium bioremediation at Rifle, Colorado

Journal Article · Mon Apr 20 04:00:00 EDT 2009 · Environmental Science&Technology

DOI:https://doi.org/10.1021/es900016v· OSTI ID:962946

Li, L; Steefel, C I; Williams, K H; Wilkins, M J; Hubbard, S S

Injection of organic carbon into the subsurface as an electron donor for bioremediation of redox-sensitive contaminants like uranium often leads to mineral transformation and biomass accumulation, both of which can alter the flow field and potentially bioremediation efficacy. This work combines reactive transport modeling with a column experiment and field measurements to understand the biogeochemical processes and to quantify the biomass and mineral transformation/accumulation during a bioremediation experiment at a uranium contaminated site near Rifle, Colorado. We use the reactive transport model CrunchFlow to explicitly simulate microbial community dynamics of iron and sulfate reducers, and their impacts on reaction rates. The column experiment shows clear evidence of mineral precipitation, primarily in the form of calcite and iron monosulfide. At the field scale, reactive transport simulations suggest that the biogeochemical reactions occur mostly close to the injection wells where acetate concentrations are highest, with mineral precipitate and biomass accumulation reaching as high as 1.5% of the pore space. This work shows that reactive transport modeling coupled with field data can be an effective tool for quantitative estimation of mineral transformation and biomass accumulation, thus improving the design of bioremediation strategies.

• Research Organization: Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA (US)
• Sponsoring Organization: Earth Sciences Division
• DOE Contract Number: AC02-05CH11231
• OSTI ID: 962946
• Report Number(s): LBNL-2079E
• Journal Information: Environmental Science&Technology, Journal Name: Environmental Science&Technology
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
58 GEOSCIENCES
ACETATES
BINDING ENERGY
BIOMASS
BIOREMEDIATION
CALCITE
CARBON
DESIGN
ELECTRONS
INJECTION WELLS
IRON
PRECIPITATION
REACTION KINETICS
SULFATES
TRANSFORMATIONS
TRANSPORT
URANIUM
VALENCE