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Development of combinatorial bacteria for metal and radionuclide bioremediation

Description: The grant concerned chromate [Cr(VI)] bioremediation and it was our aim from the outset to construct individual bacterial strains capable of improved bioremediation of multiple pollutants and to identify the enzymes suited to this end. Bacteria with superior capacity to remediate multiple pollutants can be an asset for the cleanup of DOE sites as they contain mixed waste. I describe below the progress made during the period of the current grant, providing appropriate context.
Date: June 15, 2006
Creator: Matin, A. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

High-resolution mineralogical characterization and biogeochemical modeling of uranium reaction pathways at the FRC

Description: High-Resolution Mineralogical Characterization and Biogeochemical Modeling of Uranium Reduction Pathways at the Oak Ridge Field-Research Center (FRC) Chen Zhu, Indiana University, David R. Veblen, Johns Hopkins University We have successfully completed a proof-of-concept, one-year grant on a three-year proposal from the former NABIR program, and here we seek additional two-year funding to complete and publish the research. Using a state-of-the-art 300-kV, atomic resolution, Field Emission Gun T… more
Date: June 15, 2006
Creator: Zhu, Chen
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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On the transport of emulsions in porous media

Description: Emulsions appear in many subsurface applications includingbioremediation, surfactant-enhanced remediation, and enhancedoil-recovery. Modeling emulsion transport in porous media is particularlychallenging because the rheological and physical properties of emulsionsare different from averages of the components. Current modelingapproaches are based on filtration theories, which are not suited toadequately address the pore-scale permeability fluctuations and reductionof absolute permeability that a… more
Date: June 27, 2007
Creator: Cortis, Andrea & Ghezzehei, Teamrat A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

New Technique for Speciation of Uranium in Sediments Following Acetate-Stimulated Bioremediation

Description: Acetate-stimulated bioremediation is a promising new technique for sequestering toxic uranium contamination from groundwater. The speciation of uranium in sediments after such bioremediation attempts remains unknown as a result of low uranium concentration, and is important to analyzing the stability of sequestered uranium. A new technique was developed for investigating the oxidation state and local molecular structure of uranium from field site sediments using X-Ray Absorption Spectroscopy (X… more
Date: June 22, 2011
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Microbial gene functions enriched in the Deepwater Horizon deep-sea oil plume

Description: The Deepwater Horizon oil spill in the Gulf of Mexico is the deepest and largest offshore spill in U.S. history and its impacts on marine ecosystems are largely unknown. Here, we showed that the microbial community functional composition and structure were dramatically altered in a deep-sea oil plume resulting from the spill. A variety of metabolic genes involved in both aerobic and anaerobic hydrocarbon degradation were highly enriched in the plume compared to outside the plume, indicating a g… more
Date: June 15, 2011
Creator: Lu, Z.; Deng, Y.; Nostrand, J. D. Van; He, Z.; Voordeckers, J.; Zhou, A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Hanford 100-D Area Biostimulation Soluble Substrate Field Test: Interim Data Summary for the Substrate Injection and Process Monitoring Phases of the Field Test

Description: Pacific Northwest National Laboratory is conducting a treatability test designed to demonstrate that in situ biostimulation can be applied to help meet cleanup goals in the Hanford Site 100-D Area. The in situ biostimulation technology is intended to provide supplemental treatment upgradient of the In Situ Redox Manipulation (ISRM) barrier by reducing the concentration of the primary oxidizing species in groundwater (i.e., nitrate and dissolved oxygen) and chromate, and thereby increasing the l… more
Date: June 1, 2008
Creator: Truex, Michael J.; Vermeul, Vincent R.; Mackley, Rob D.; Fritz, Brad G.; Mendoza, Donaldo P.; Johnson, Christian D. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Reduction and Reoxidation of Soils During & After Uranium Bioremediation; Implications for Long-Term Uraninite Stability & Bioremediation Scheme Implementation

Description: This research focuses on the conditions and rates under which uranium will be remobilized after it has been precipitated biologically, and what alterations can be implemented to increase its long-term stability in groundwater after the injection of an electron donor has been discontinued. Furthermore, this research addresses short-term iron reoxidation as a mechanism to enhance/extend uranium bioremediation under iron reduction, without its remobilization. The research to date has focused on lo… more
Date: June 1, 2005
Creator: Jaffe, Peter R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Genes for Uranium Bioremediation in the Anaerobic Sulfate-Reducing Bacteria

Description: Surprising results were obtained following an attempt to induce or derepress the machinery for U(VI) reduction by growing Desulfovibrio desulfuricans G20 in the presence of 1 mM uranyl acetate. G20 cells grown on lactate-sulfate medium amended with U(VI) reduced uranium at a slower rate than cells grown in the absence of this metal. When periplasmic extracts of these cells were prepared, Western analysis of the proteins revealed that the cytochrome c3 was absent. This observation has been furth… more
Date: June 1, 2003
Creator: Wall, Judy D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

In Situ Immobilization of Uranium in Structured Porous Media via Biomineralization at the Fracture/Matrix Interface

Description: Although the biogeochemical processes underlying key bioremediation technologies are increasingly well understood, field-scale heterogeneity (both physical and biogeochemical) remains a major obstacle to successful field-scale implementation. In particular, slow release of contamination from low-permeability regions (primarily by diffusive/dispersive mass transfer) can hinder the effectiveness of remediation. This research aims to evaluate strategies that target bioremediation efforts at interf… more
Date: June 1, 2006
Creator: Scheibe, Timothy D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Ecological Interactions Between Metals and Microbes That Impact Bioremediation

Description: Previous work showed the correlation between bacterial biomass, population structure and the amount of lead, chromium and aromatic compounds present along a 21.6 m transect in which the concentrations of both heavy metals (Pb and Cr) and aromatic compounds varied 2-3 orders of magnitude. This work suggested that (a) biomass level was better correlated to the level of biodegradable organic C than the level of heavy metals, (b) microbial community composition differed between highly contaminated … more
Date: June 1, 2003
Creator: Konopka, Allan E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Field-Integrated Studies of Long-Term Sustainability of Chromium Bioreduction at Hanford 100H Site

Description: The objectives of the project are to investigate coupled hydraulic, geochemical, and microbial conditions, and to determine the critical biogeochemical parameters necessary to maximize the extent of Cr(VI) bioreduction and minimize Cr(III) reoxidation in groundwater. Specific goals of the project are as follows: (1) Field testing and monitoring of Cr(VI) bioreduction in ground water and its transformation into insoluble species of Cr(III) at the Hanford 100H site, to develop the optimal strateg… more
Date: June 1, 2006
Creator: Long, Philip E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

New Catalytic DNA Biosensors for Radionuclides and Metal ions

Description: The goals of the project are to develop new catalytic DNA biosensors for simultaneous detection and quantification of bioavailable radionuclides and metal ions, and apply the sensors for on-site, real-time assessment of concentration, speciation and stability of the individual contaminants during and after bioremediation. A negative selection strategy was tested and validated. In vitro selection was shown to yield highly active and specific transition metal ion-dependent catalytic DNA/RNA. A fl… more
Date: June 1, 2003
Creator: Lu, Yi
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Modeling Biodegradation and Reactive Transport: Analytical and Numerical Models

Description: The computational modeling of the biodegradation of contaminated groundwater systems accounting for biochemical reactions coupled to contaminant transport is a valuable tool for both the field engineer/planner with limited computational resources and the expert computational researcher less constrained by time and computer power. There exists several analytical and numerical computer models that have been and are being developed to cover the practical needs put forth by users to fulfill this sp… more
Date: June 9, 2005
Creator: Sun, Y & Glascoe, L
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Ecological Interactions Between Metals and Microbes That Impact Bioremediation

Description: Bacterial Community Diversity at a Mixed Waste Contaminated Site The correlation between bacterial population structure and lead, chromium and organic compounds present along a 21.6 m transect was examined. There was a gradient of heavy metal (Cr and Pb) and petroleum hydrocarbon contamination in these soils. A 16S rDNA analysis method and fatty acid methyl esters derived from phospholipids (PLFA) analysis were used to compare microbial communities. Soil microbial DNA was extracted and communit… more
Date: June 1, 2001
Creator: Konopka, Allan E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Mesoscale Tank Experiments for Investigating Carbon Tetrachloride Biodegradation

Description: Mesoscale tank experiments were performed to simulate bioremediation of saturated zone carbon tetrachloride (CCl4) originating from a vadose zone carbon tetrachloride source. The mesoscale tank is 2-m wide by 2-m high by 3-m long and was constructed of stainless steel, yielding a total volume of 12 m3. Simulated geology within the tank consisted of two unconsolidated sand layers separated by a clay layer containing variable-sized stainless steel tubes that represented fractures within a consoli… more
Date: June 1, 2005
Creator: Lee, Brady D. & Lenhard, Robert J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Field-Integrated Studies of Long-Term Sustainability of Chromium Bioreduction at Hanford 100H Site

Description: The objectives of the project are to investigate coupled hydraulic, geochemical, and microbial conditions, and to determine the critical biogeochemical parameters necessary to maximize the extent of Cr (VI) bioreduction and minimize Cr(III) reoxidation in groundwater.
Date: June 1, 2006
Creator: Long, Phillip E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Ecological Interactions Between Metals and Microbes That Impact Bioremediation

Description: Samples have been obtained from (a) soil highly contaminated with Cr (tannery site) and (b) soils contaminated with petroleum, Cr, and Pb (Seymour, IN). Microcosm experiments with the tannery site soil indicated that microbial biomass (assayed as phospholipid-phosphate) and activity (assayed as carbon dioxide evolution) were primarily determined by organic carbon availability, but not total Cr concentration. The toxicity of metals to the indigenous microbial populations of the Seymour soils was… more
Date: June 1, 1998
Creator: Konopka, Allan E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Field-scale evaluation of biological uranium reduction and reoxidation in the near-source zone at the NABIR Field Research Center in Oak Ridge, TN

Description: The primary objective of the project is to advance the understanding and predictive capability of coupled hydrological, geochemical, and microbiological processes that control the in situ transport and bioremediation radionuclides and co-contaminants at multiple scales. Specific objectives include: (1) Investigate the feasibility of in situ bioremediation of uranium in a highly contaminated region within the subsurface of Area 3 of the DoE ERSP FRC (2) Using a variety of tracer strategies, deve… more
Date: June 1, 2006
Creator: Criddle, Craig S.; Kitanidis, Peter; Fendorf, Scott; Wu, Weimin; Jardine, Philip M.; Zhou, Jizhong et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Identification of Metal Reductases using Proteomic Analysis

Description: Central to the NABIR goal to develop the scientific basis for in situ remediation of radioactive contaminants is the fundamental understanding of microorganisms with dissimilatory metal reducing activity. In order to effectively exploit these bacteria, it is necessary to know which enzymes and pathways are involved. Additionally, it would be advantageous to understand the similarities and differences of these pathways across different bacteria for effective deployment in bioremediation, as well… more
Date: June 1, 2006
Creator: Lipton, Mary
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Genes for Uranium Bioremediation in the Anaerobic Sulfate-Reducing Bacteria

Description: The objectives of the previous grant period were designed to explore the electron transport pathway employed by the sulfate-reducing bacteria (SRB) for the reduction of U(VI) to U(IV). More specifically experiments were designed to determine whether U(VI) reduction by members of the genus Desulfovibrio was mediated by a unique, dedicated reductase or occurred as a fortuitous reaction with a reductase naturally involved in alternative reduction processes. In addition, the regulation of the hiera… more
Date: June 1, 2001
Creator: Wall, Judy D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Mass Balance: A Key to Advancing Monitored and Enhanced Attenuation for Chlorinated Solvents

Description: Monitored natural attenuation (MNA) and enhanced attenuation (EA) are two environmental management strategies that rely on a variety of attenuation processes to degrade or immobilize contaminants and are implemented at appropriate sites by demonstrating that contaminant plumes have low risk and are stable or shrinking. The concept of a mass balance between the loading and attenuation of contaminants in a groundwater system is a powerful framework for conceptualizing and documenting the relative… more
Date: June 30, 2006
Creator: Looney, B.; Karen Vangelas, K.; Karen-M Adams, K.; Chappelle, Francis H.; Early, Tom O. & Sink, Claire H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Biotransformation involved in sustained reductive removal of uranium in contaminant aquifers

Description: This report summarizes progress made from June 2003 to July 2004. During this period research focused on further understanding the factors controlling the growth and activity of dissimilatory metal reducers in subsurface environments and the application of these findings to better design of strategies for in situ bioremediation of uranium.
Date: June 1, 2004
Creator: Lovley, Derek R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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