WorldCat Identities

United States Department of Energy Environmental Management Science Program

Overview
Works: 1,652 works in 1,680 publications in 1 language and 13,359 library holdings
Roles: Researcher, Sponsor
Publication Timeline
.
Most widely held works about United States
 
moreShow More Titles
fewerShow Fewer Titles
Most widely held works by United States
Ecological Interactions Between Metals and Microbes( )

2 editions published between 2004 and 2005 in English and held by 12 WorldCat member libraries worldwide

Analyses of chromium resistant microbes. Culturable xylene-degrading and chromate-resistant microbes were obtained from chronically cocontaminated soil using a microcosm enrichment technique, and shown to correlate to dominant soil populations using culture independent techniques. The soil microbial community proved able to mount a respiratory response to addition of xylene in the presence of chromate. The majority of isolates belonged to the ubiquitous but poorly studied high %G+C Gram positive genus Arthrobacter, and exhibited considerable genotypic and phenotypic variability. Phenotypic assays uncovered a wide variation in the levels of chromate resistance, even between very closely related strains. Primers designed against conserved motifs in the known chrA chromate efflux gene failed to detect similar sequences among the chromate resistant Arthrobacter isolates obtained through enrichment
Reactive Membrane Barriers for Containment of Subsurface Contamination( )

2 editions published between 2005 and 2006 in English and held by 12 WorldCat member libraries worldwide

This report focuses on progress made in the last 12 months, with prior results briefly summarized. We emphasize that the key to our work is an increase in barrier properties. Thus, much of our work has focused on poor, thin barriers composed of PVA. WE have done so because experiments are then able to be conducted over reasonable times. At the same time, we have developed and experimentally verified theories showing how our short experiments can be extrapolated to real situations
Overcoming Barriers to the Remediation of Carbon Tetrachloride Through Manipulation of Competing Reaction Mechanisms( )

2 editions published in 2004 in English and held by 11 WorldCat member libraries worldwide

Most approaches that have been proposed for the remediation of groundwater contaminated with carbon tetrachloride produce chloroform as the major product and methylene chloride as a minor product. Both of these products are nearly as persistent and problematic as the parent compound, but competing reaction pathways produce the more desirable products carbon monoxide and/or formate. Branching between these reaction pathways is highly variable, but the controlling factors have not been identified. To improve the applicability of reductive remediation technologies to the large plumes of carbon tetrachloride at several DOE sites, we are pursuing the complete characterization of the mechanisms and kinetics of competing degradation reactions of carbon tetrachloride through laboratory experiments closely coordinated with theoretical modeling studies. The results are beginning to suggest strategies for maximizing the yield of desirable products from carbon tetrachloride degradation, which will be tested in column model systems using real site waters and matrix materials
High Temperature Condensed Phase Mass Spectrometric Analysis( )

2 editions published between 1999 and 2000 in English and held by 10 WorldCat member libraries worldwide

This program (in the 20th month as of this writing) was initiated with the goal of designing, constructing and operating a materials analysis instrument capable of obtaining a wide variety of chemical measurements on a material at high temperature. This instrument is being built around a quadrupole mass spectrometer. There are three main modes of obtaining spectra from the high temperature condensed phase material; surface ionization from the condensed phase, secondary ion mass spectrometry (SIMS, both static and dynamic modes) of the condensed phase, and electron impact ionization of vapor phase neutral species. The combination of the data from these three modes will allow the gleaning of chemical information concerning the nature of the chemical species present in both the condensed phase (solid or molten) and the vapor phase. The intended application is the identification of the chemical species present in materials at high temperatures
An Integrated Assessment of Geochemical and Community Structure Determinants of Metal Reduction Rates in Subsurface Sediments( )

1 edition published in 2005 in English and held by 8 WorldCat member libraries worldwide

Our current research represents a joint effort between Oak Ridge National Laboratory (ORNL), Florida State University (FSU), and the University of Tennessee. ORNL will serve as the lead institution with Dr. A.V. Palumbo responsible for project coordination, integration, and deliverables. This project was initiated in November, 2004, in the Integrative Studies Element of the NABIR program. The overall goal of our project is to provide an improved understanding of the relationships between microbial community structure, geochemistry, and metal reduction rates. The research seeks to address the following questions: Is the metabolic diversity of the in situ microbial community sufficiently large and redundant that bioimmobilization of uranium will occur regardless of the type of electron donor added to the system? Are their donor specific effects that lead to enrichment of specific community members that then impose limits on the functional capabilities of the system? Will addition of humics change rates of uranium reduction without changing community structure? Can resource-ratio theory be used to understand changes in uranium reduction rates and community structure with respect to changing C:P ratios?
Defining Conditions for Maximizing Bioreduction of Uranium( )

1 edition published in 2004 in English and held by 8 WorldCat member libraries worldwide

Correlations between modifying electron donor and acceptor accessibility, the in-situ microbial community, and bioreduction of Uranium at the FRC and UMTRA research sites indicated that significant modifications in the rate, amount and by inference the potential stability of immobilized Uranium are feasible in these environments. The in-situ microbial community at these sites was assessed with a combination of lipid and real-time molecular techniques providing quantitative insights of effects of electron donor and manipulations. Increased (9mM in 2003 vs 3mM 2002) donor amendment at the Old Rifle site resulted in the stimulation of anaerobic conditions downgradient of the injection gallery. Biomass within the test plot increased relative to the control well at 17 feet. Q-PCR specific for IRB/SRB showed increased copy numbers within the test plot and was the highest at the injection gallery. Q-PCR specific for Geobacter sp. showed increased copy numbers within the test plot but further downgradient from the injection gallery than the SRB/IRB. DNA and Lipid analysis confirm changes in the microbial community structure due to donor addition. See also the PNNL (Long) and UMASS (Anderson) posters for more information about this site
Stabilization of Plutonium in Subsursface Environments via Microbial Reduction and Biofilm Formation( )

1 edition published in 2005 in English and held by 8 WorldCat member libraries worldwide

Our work is towards mechanistically understanding interactions of unsaturated bacterial biofilms and their extracellular polymeric substances (EPS) with actinide metals and metal surrogates under vadose zone conditions. Because metal contaminants in the vadose zone co-occur with organic pollutants, some of our work has included experiments with organic pollutants
Mineral Surface Processes Responsible for the Decreased Retardation (or Enhanced Mobilization) of 137 Cs from HWL Tank Discharges( )

1 edition published in 1999 in English and held by 7 WorldCat member libraries worldwide

Experimental research will determine how the sorption chemistry of Cs on Hanford vadose zone sediments changes after contact with solutions characteristic of high-level tank wastes (HLW). Our central hypothesis is that the high ionic-strength of tank wastes (i.e.,> 5 mol/L NaNO3) will suppress all surface-exchange reactions of Cs, except those to the highly selective frayed edge sites (FES) of the micaceous fraction. We further speculate that the concentrations, ion selectivity, and structural aspects of the FES will change after contact with the harsh chemical conditions of HLW and these changes will be manifest in the macroscopic sorption behavior of Cs. We believe that migration predictions of Cs can be improved substantially if such changes are understood and quantified. The research will integrate studies of ion-exchange thermodynamics on the FES, with high resolution surface microscopies and spectroscopy to probe the structure of FES in Hanford sediments and to describe how the chemical environment of sorbed Cs changes when HLW supernatants promote silica dissolution and aluminum precipitation. Newly available atomic-force microscopies and high-resolution electron-beam microscopies afford previously unavailable opportunities to visualize and characterize FES. Our overall goal is to provide knowledge that will improve transport calculations of Cs in the tank-farm environment. Specifically, the research will: Identify how the macroscopic sorption behavior of Cs on the micaceous fraction of the Hanford sediments changes after contact with simulants of HLW tank supernatants over a range of relevant chemical ([OH], [Na], [Al], [K, NH4]) and temperature conditions (23-80 C). Reconcile observed changes in sorption chemistry with microscopic and molecular changes in adsorption-site distribution, chemistry, mineralogy, and morphology/structure of the micaceous sorbent fraction. Integrate mass-action-solution-exchange measurements with changes in the structure/site distribution of the micaceous-sorbent fraction to yield a multi-component/site-exchange model relevant to high ionic strength and hydroxide concentrations for prediction of environmental Cs sorption
Precipitation and Deposition of Aluminum-Containing Phases in Tank Wastes( )

1 edition published in 1999 in English and held by 7 WorldCat member libraries worldwide

The goal of this work is to understand the kinetics of dissolution, precipitation, and scale formation involving aluminum-containing phases in alkaline salt solutions representative of tank wastes. This research will identify aluminum-containing phases that are likely to form or be present, and predict conditions under which such phases are likely to form or be present. Experiments will identify processing conditions that either promote or inhibit the heterogeneous or homogeneous nucleation and growth of aluminum-containing phases to form precipitates or scales. Test conditions will encompass conditions anticipated for waste storage, washing, leaching, concentration in evaporators, and contact with pipes, ion exchangers, and other processing media
Ion Recognition Approach to Volume Reduction of Alkaline Tank Waste by Separation of Sodium Salts( )

1 edition published in 2005 in English and held by 7 WorldCat member libraries worldwide

The purpose of this research involving collaboration between Oak Ridge National Laboratory (ORNL) and Pacific Northwest National Laboratory (PNNL) is to explore new approaches to the separation of sodium hydroxide, sodium nitrate, and other sodium salts from high-level alkaline tank waste. The principal potential benefit is a major reduction in disposed waste volume, obviating the building of expensive new waste tanks and reducing the costs of low-activity waste immobilization. Principles of ion recognition are being researched toward discovery of liquid-liquid extraction systems that selectively separate sodium hydroxide and sodium nitrate from other waste components. The successful concept of pseudohydroxide extraction using fluorinated alcohols and phenols is being developed at ORNL and PNNL toward a greater understanding of the controlling equilibria, role of solvation, and of synergistic effects involving crown ethers. Synthesis efforts are being directed toward enhanced sodium binding by crown ethers, both neutral and proton-ionizable. Studies with real tank waste at PNNL will provide feedback toward solvent compositions that have promising properties
Actinides in Hanford Tank Waste Simulants : Chemistry of Selected Species in Oxidizing Alkaline Solutions( )

1 edition published in 2004 in English and held by 7 WorldCat member libraries worldwide

To enhance removal of selected troublesome nonradioactive matrix elements (P, Cr, Al, S) from the sludges in radioactive waste tanks at the Hanford site, various chemical washing procedures have been evaluated. It is intended that leaching should leave the actinides in the residual sludge phase for direct vitrification. Oxidative treatment with strongly alkaline solutions has emerged as the best approach to accomplishing this feat. However, because the most important actinide ions in the sludge can exist in multiple oxidation states, it is conceivable that changes in actinide oxidation state speciation could interfere with hopes and plans for actinide insolubility. In this presentation, we discuss both the impact of oxidative alkaline leachants on actinide oxidation state speciation and the chemistry of oxidized actinide species in the solution phase. Actinide oxidation does occur during leaching, but the solubility behavior is complex. Mixed ligand complexes may dominate solution phase speciation of actinides under some circumstances. This work was supported by the U.S. Department of Energy, Offices of Science and Waste Management, Environmental Management Science Program under Contract DEAC03- 76SF0098 at Lawrence Berkeley National Laboratory and Contract W-31-109- ENG-38 at Argonne National Laboratory
Rational Synthesis of Imprinted Organofunctional Sol-Gel Materials for Toxic Metal Separation( )

1 edition published in 1999 in English and held by 7 WorldCat member libraries worldwide

The objective of this program is to rationally design and synthesize imprinted sol-gel SiO2 and SiO2/M'O2 (M' = Ti, Zr) materials containing Si-X-L binding groups through template approaches and develop a scientific basis for metal ion binding and recognition by such imprinted organofunctional materials. Removal of metal ions from aqueous solutions by hydrophilic metal oxide-based materials is expected to be fast in comparison to hydrophobic organic polymers and the imprinted binding sites are expected to exhibit enhanced selectivity and affinity of target metal ions
Numerical Modeling of Mixing of Chemically Reacting, Non-Newtonian Slurry for Tank Waste Retrieval( )

1 edition published in 2001 in English and held by 7 WorldCat member libraries worldwide

In the U.S. Department of Energy (DOE) complex, 100 million gallons of radioactive and chemical wastes from plutonium production are stored in 281 underground storage tanks. Retrieval of the wastes from the tanks is the first step in its ultimate treatment and disposal. Because billions of dollars are being spent on this effort, waste retrieval demands a strong scientific basis for its successful completion. As will be discussed in Section 4.2, complex interactions among waste chemical reactions, rheology, and mixing of solid and liquid tank waste (and possibly with a solvent) will occur in DSTs during the waste retrieval (mixer pump) operations. The ultimate goal of this study was to develop the ability to simulate the complex chemical and rheological changes that occur in the waste during processing for retrieval. This capability would serve as a scientific assessment tool allowing a priori evaluation of the consequences of proposed waste retrieval operations. Hanford tan k waste is a multiphase, multicomponent, high-ionic strength, and highly basic mixture of liquids and solids. Wastes stored in the 4,000-m3 DSTs will be mixed by 300-hp mixer pumps that inject high-speed (18.3 m/s) jets to stir up the sludge and supernatant liquid for retrieval. During waste retrieval operations, complex interactions occur among waste mixing, chemical reactions, and associated rheology. Thus, to determine safe and cost-effective operational parameters for waste retrieval, decisions must rely on new scientific knowledge to account for physical mixing of multiphase flows, chemical reactions, and waste rheology. To satisfy this need, we integrated a computational fluid dynamics code with state-of-the-art equilibrium and kinetic chemical models and non-Newtonian rheology (Onishi et al. 1999). This development is unique and holds great promise for addressing the complex phenomena of tank waste retrieval. The current model is, however, applicable only to idealized tank waste conditions-solids are crystals, not hydrates; kinetic rates are fast; the slurry has simple rheology; and the water mass is constant. Thus, this idealized reactive transport model, ARIEL could provide a basis for addressing potentially crippling waste retrieval issues associated with hydrated mineral formation by systematically expanding its modeling capabilities
Physical Characterization of Solid-Liquid Slurries at High Weight Fractions Using Optical and Ultrasonic Methods( )

1 edition published in 2002 in English and held by 7 WorldCat member libraries worldwide

The goal of this proposed work is to directly address the need for rapid on-line characterization of the physical properties of HLW slurries during all phases of the remediation process, from in-tank characterization of sediments to monitoring of the concentration, particle size, and degree of agglomeration and gelation of slurries during transport. This will be done with both optical and ultrasonic methods. There are three tasks: (1) develop optical and acoustic measurements to provide the fundamental science needed for successful device development and implementation, (2) develop theories that describe the interrelationship between wave propagation and the physical properties of the slurry, and (3) solve, in the framework of these theories, the inversion problem and compare them with the experimental measurements to non-intrusively characterize slurries
New Silicotitanate Waste Forms ; Development and Characterization( )

1 edition published in 2001 in English and held by 7 WorldCat member libraries worldwide

The objective of this program is to identify new waste forms and disposal strategies specific to crystalline silicotitanate (CST) secondary waste generated from Cs and Sr ion exchange processes. Waste forms developed in this work will offer an alternative to current disposal plans. The goals of the program are to reduce the costs associated with CST waste disposal, to minimize the risk of contamination to the environment during CST processing, and to provide DOE with technical alternatives for CST disposal. The technical objectives of the proposed work are to fully characterize the phase relationships, structures, and thermodynamic and kinetic stabilities of CST waste forms and to establish a sound technical basis for understanding key waste form properties such as melting temperatures and aqueous durability, based on an in-depth understanding of waste form structures and thermochemistry
A Hydrologic-Geophysical Method for Characterizing Flow and Transport Processes within the Vadose Zone( )

1 edition published in 2000 in English and held by 7 WorldCat member libraries worldwide

The objective of this study is to analyze flow within the vadose zone during a mid-scale hydrologic test to and to characterize transport processes in-situ. This project will employ numerical and experimental tools that have been developed under a previously funded EMSP proposal (project number 55332). Geophysical imaging techniques will be employed to image the changes produced by the transport experiments in-situ as they occur. Results will help to better understand flow and transport modes within the vadose zone at DOE sites, including the influence of natural heterogeneities and man-made structures. In addition the data will provide checks against which numerical flow and transport simulations can be compared
''The Influence of Calcium Carbonate Grain Coatings on Contaminant Reactivity in Vadose Zone Sediments''( )

1 edition published in 2003 in English and held by 7 WorldCat member libraries worldwide

Our component of this project focuses on the reaction of contaminant-containing fluids with carbonate mineral surfaces in order to better understand the dissolution-growth and related solid-solution processes that ultimately affect contaminant mobility in settings containing carbonates or carbonate grain coatings. Our collaborators (Stanford, PNNL) have focused on other aspects of carbonate and carbonate mineral surfaces as part of the overall project. Because some of the sediments through which contaminants leaking from the Hanford waste have carbonate grain coatings; better understanding the chemistry of carbonate-contaminant interaction constitutes fundamental chemistry needed in order to construct better models of contaminant transport through carbonate-containing sediments
Radiolytic and Thermal Process Relevant to Dry Storage of Spent Nuclear Fuels( )

1 edition published in 1999 in English and held by 7 WorldCat member libraries worldwide

This project involves basic research in chemistry and physics aimed at providing information pertinent to the safe long-term dry storage of spent nuclear fuel (SNF), thousands of tons of which remain in water storage across the DOE complex. The Hanford Site K-Basins alone hold 2300 tons of spent fuel, much of it severely corroded, and similar situations exist at Savannah River and Idaho National Engineering and Environmental Laboratory. DOE plans to remove this fuel and seal it in overpack canisters for ''dry'' interim storage for up to 75 years while awaiting permanent disposition. Chemically bound water will remain in this fuel even after the proposed drying steps, leading to possible long-term corrosion of the containers and/or fuel rods themselves, generation of H2 and O2 gas via radiolysis (which could lead to deflagration or detonation), and reactions of pyrophoric uranium hydrides. No thoroughly tested model is now available to predict fuel behavior during preprocessing, processing, or storage. In a collaborative effort among Rutgers University, Pacific Northwest National Laboratory, and Brookhaven National Laboratory, we are studying the radiolytic reaction, drying processes, and corrosion behavior of actual SNF materials and of pure and mixed-phase samples. We propose to determine what is omitted from current models: radiolysis of water adsorbed on or in hydrates or hydroxides, thermodynamics of interfacial phases, and kinetics of drying. A model will be developed and tested against actual fuel rod behavior to ensure validity and applicability to the problems associated with developing dry storage strategies for DOE-owned SNF
Remote Manipulation for D & D Exhibiting Teleautonomy and Telecollaboration( )

1 edition published in 2003 in English and held by 7 WorldCat member libraries worldwide

The purpose of the work is to enhance remote operations of robotic systems for D & D tasks by extending teleoperation with semi-autonomous functions. The work leverages the $1.2M dual-arm work platform (DAWP) developed with broad participation for the CP5 D & D, as well as 2,000 hr DAWP D & D operational experience. We propose to develop a reactive, agent-based control architecture well suited to unstructured and unpredictable environments, and cobot control technology, which implements a virtual fixture that can be used to guide the application of tools with force-feedback control. Developed methodologies will be implemented using a structured light sensor and cobot hand controller on the dual-arm system
Quantifying and Predicting Reactive Transport of Uranium in Waste Plumes( )

1 edition published in 2005 in English and held by 6 WorldCat member libraries worldwide

The Hanford Site is the DOE's largest legacy waste site, with uranium (U) from plutonium processing being a major contaminant in its subsurface. Accident release of highly concentrated high level wastes (e.g. 0.5 lb U(VI)/gal) left large quantities of U in the vadose zone under tank farms (e.g. 7-8 tons U(VI) under tank BX-102 (Jones et al., 2001)). The U contamination has been found in groundwater in both 300 and 200 Areas of Hanford, indicating U(VI) was/is mobile. Because excavation costs are enormous, this U will likely be left in-ground for the foreseeable future. Therefore, understanding the contamination processes and the resulting U spatial and temporary distributions and mobility in the heavily contaminated Hanford site is needed in order to forecast its future transport. The overall objective of this research is to develop an experimentally supported conceptual model of U reactive transport, during and after the tank leakage, at heavily U-contaminated areas of the Hanford vadose zone. The conceptual model will incorporate key geochemical and physical controls on the contamination process, explain the current distribution of U in the vadose zone, and guide predictions of its future mobility under the influence of natural recharge. We do not seek to predict the complex flow geometry of any specific waste plume. Instead, our work is trying to identify the hierarchy of processes relevant along U waste plume paths
 
moreShow More Titles
fewerShow Fewer Titles
Audience Level
0
Audience Level
1
  Kids General Special  
Audience level: 0.15 (from 0.02 for Research n ... to 1.00 for Research n ...)

Covers
Research Needs in Subsurface Science: U.S. Department of Energy's Environmental Management Science Program (Compass series)Nuclear site remediation : first accomplishments of the Environmental Management Science ProgramSubsurface contamination remediation : accomplishments of the Environmental Management Science ProgramResearch needs for high-level waste stored in tanks and bins at U.S. Department of Energy sites : Environmental Management Science ProgramResearch Needs in Subsurface Science : U.S. Department of Energy's Environmental Management Science ProgramNuclear site remediation : first accomplishments of the Environmental Management Science Program ; [... symposium ... at the 218th National Meeting of the American Chemical Society in New Orleans, Louisiana ...]
Alternative Names

controlled identityUnited States. Department of Energy

E.M.S.P.

EMSP

United States. Dept. of Energy. Environmental Management Science Program

Languages
English (55)