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The Effect of Government Actions on Environmental Technology Innovation: Applications to the Integrated Assessment of Carbon Sequestration Technologies

Description: This project seeks to improve the ability of integrated assessment models (IA) to incorporate changes in technology, especially environmental technologies, cost and performance over time. In this report, we present results of research that examines past experience in controlling other major power plant emissions that might serve as a reasonable guide to future rates of technological progress in carbon capture and sequestration (CCS) systems. In particular, we focus on U.S. and worldwide experience with sulfur dioxide (SO{sub 2}) and nitrogen oxide (NO{sub x}) control technologies over the past 30 years, and derive empirical learning rates for these technologies. The patterns of technology innovation are captured by our analysis of patent activities and trends of cost reduction over time. Overall, we found learning rates of 11% for the capital costs of flue gas desulfurization (FGD) system for SO{sub 2} control, and 13% for selective catalytic reduction (SCR) systems for NO{sub x} control. We explore the key factors responsible for the observed trends, especially the development of regulatory policies for SO{sub 2} and NO{sub x} control, and their implications for environmental control technology innovation.
Date: January 15, 2004
Creator: Rubin, E. S.; Hounshell, D. A.; Yeh, S.; Taylor, M.; Schrattenholzer, L.; Riahi, K. et al.
Partner: UNT Libraries Government Documents Department

Characterization of Post-Cleaning Solids Samples from the 2H Evaporator Pot

Description: Samples retrieved from the 2H Evaporator Pot in October of 2003 were of a similar nature as previous materials. The bulk of the sample was comprised of a sodium aluminosilicate phase, cancrinite. The concentration of uranium in the evaporator solids,however, was very low:less than 0.1 percentage weight. The uranium enrichment was depleted as expected and measured 0.6 percent. These data agree with uranium contents generated during experimental testing. Additionally, the overall specific radionuclide content is lower for this sample than previous measured on samples from the Gravity Drain Line in 1997 and the cone and wall in 2000.
Date: March 15, 2004
Creator: WILMARTH, WILLIAM
Partner: UNT Libraries Government Documents Department

Features, Events, and Processes: system Level

Description: The purpose of this analysis report is to evaluate and document the inclusion or exclusion of the system-level features, events, and processes (FEPs) with respect to modeling used to support the total system performance assessment for the license application (TSPA-LA). A screening decision, either Included or Excluded, is given for each FEP along with the technical basis for screening decisions. This information is required by the U.S. Nuclear Regulatory Commission (NRC) at 10 CFR 63.113 (d, e, and f) (DIRS 156605). The system-level FEPs addressed in this report typically are overarching in nature, rather than being focused on a particular process or subsystem. As a result, they are best dealt with at the system level rather than addressed within supporting process-level or subsystem-level analyses and models reports. The system-level FEPs also tend to be directly addressed by regulations, guidance documents, or assumptions listed in the regulations; or are addressed in background information used in development of the regulations. For included FEPs, this analysis summarizes the implementation of the FEP in the TSPA-LA (i.e., how the FEP is included). For excluded FEPs, this analysis provides the technical basis for exclusion from the TSPA-LA (i.e., why the FEP is excluded). The initial version of this report (Revision 00) was developed to support the total system performance assessment for site recommendation (TSPA-SR). This revision addresses the license application (LA) FEP List (DIRS 170760).
Date: October 15, 2004
Creator: McGregor, D.
Partner: UNT Libraries Government Documents Department

Climate Change Technology Scenarios: Energy, Emissions, and Economic Implications

Description: This report describes three advanced technology scenarios and various illustrative cases developed by staff of Pacific Northwest National Laboratory (PNNL) for the U.S. Climate Change Technology Program. These scenarios and illustrative cases explore the energy, emissions and economic implications of using advanced energy technologies and other climate change related technologies to reduce future emissions of greenhouse gases (GHGs). The cases were modeled using the Mini Climate Assessment Model (MiniCAM) developed by PNNL. The report describes the scenarios, the specifications for the cases, and the results. The report also provides background information on current emissions of GHGs and issues associated with stabilizing GHG concentrations.
Date: August 15, 2004
Creator: Placet, Marylynn; Humphreys, Kenneth K. & Mahasenan, N Maha
Partner: UNT Libraries Government Documents Department

Reaction selectivity studies on nanolithographically-fabricated platinum model catalyst arrays

Description: In an effort to understand the molecular ingredients of catalytic activity and selectivity toward the end of tuning a catalyst for 100% selectivity, advanced nanolithography techniques were developed and utilized to fabricate well-ordered two-dimensional model catalyst arrays of metal nanostructures on an oxide support for the investigation of reaction selectivity. In-situ and ex-situ surface science techniques were coupled with catalytic reaction data to characterize the molecular structure of the catalyst systems and gain insight into hydrocarbon conversion in heterogeneous catalysis. Through systematic variation of catalyst parameters (size, spacing, structure, and oxide support) and catalytic reaction conditions (hydrocarbon chain length, temperature, pressures, and gas composition), the data presented in this dissertation demonstrate the ability to direct a reaction by rationally adjusting, through precise control, the design of the catalyst system. Electron beam lithography (EBL) was employed to create platinum nanoparticles on an alumina (Al{sub 2}O{sub 3}) support. The Pt nanoparticle spacing (100-150-nm interparticle distance) was varied in these samples, and they were characterized using x-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM), both before and after reactions. The TEM studies showed the 28-nm Pt nanoparticles with 100 and 150-nm interparticle spacing on alumina to be polycrystalline in nature, with crystalline sizes of 3-5 nm. The nanoparticle crystallites increased significantly after heat treatment. The nanoparticles were still mostly polycrystalline in nature, with 2-3 domains. The 28-nm Pt nanoparticles deposited on alumina were removed by the AFM tip in contact mode with a normal force of approximately 30 nN. After heat treatment at 500 C in vacuum for 3 hours, the AFM tip, even at 4000 nN, could not remove the platinum nanoparticles. The increase of adhesion upon heat treatment indicates stronger bonding between the Pt and the support at the metal-oxide interface.
Date: May 15, 2004
Creator: Grunes, Jeffrey Benjamin
Partner: UNT Libraries Government Documents Department

Biosphere dose conversion Factor Importance and Sensitivity Analysis

Description: This report presents importance and sensitivity analysis for the environmental radiation model for Yucca Mountain, Nevada (ERMYN). ERMYN is a biosphere model supporting the total system performance assessment (TSPA) for the license application (LA) for the Yucca Mountain repository. This analysis concerns the output of the model, biosphere dose conversion factors (BDCFs) for the groundwater, and the volcanic ash exposure scenarios. It identifies important processes and parameters that influence the BDCF values and distributions, enhances understanding of the relative importance of the physical and environmental processes on the outcome of the biosphere model, includes a detailed pathway analysis for key radionuclides, and evaluates the appropriateness of selected parameter values that are not site-specific or have large uncertainty.
Date: October 15, 2004
Creator: Wasiolek, M.
Partner: UNT Libraries Government Documents Department

An Automated System for Measuring Microphysical and Radiative Cloud Characteristics from a Tethered Balloon

Description: OAK-B135 The rate of climate change in polar regions is now felt to be a harbinger of possible global warming. Long-lived, relatively thin stratus clouds play a predominant role in transmitting solar radiation and trapping long wave radiation emitted from open water and melt ponds. In situ measurements of microphysical and radiative properties of Arctic and Antarctic stratus clouds are needed to validate retrievals from remote measurements and simulations using numerical models. While research aircraft can collect comprehensive microphysical and radiative data in clouds, the duration of these aircraft is relatively short (up to about 12 hours). During the course of the Phase II research, a tethered balloon system was developed that supports miniaturized meteorological, microphysical and radiation sensors that can collect data in stratus clouds for days at a time. The tethered balloon system uses a 43 cubic meter balloon to loft a 17 kg sensor package to altitudes u p to 2 km. Power is supplied to the instrument package via two copper conductors in the custom tether. Meteorological, microphysical and radiation data are recorded by the sensor package. Meteorological measurements include pressure, temperature, humidity, wind speed and wind direction. Radiation measurements are made using a 4-pi radiometer that measures actinic flux at 500 and 800 nm. Position is recorded using a GPS receiver. Microphysical data are obtained using a miniaturized version of an airborne cloud particle imager (CPI). The miniaturized CPI measures the size distribution of water drops and ice crystals from 9 microns to 1.4 mm. Data are recorded onboard the sensor package and also telemetered via a 802.11b wireless communications link. Command signals can also be sent to the computer in the sensor package via the wireless link. In the event of a broken tether, a GMRS radio link to the balloon package is used ...
Date: March 15, 2004
Creator: Lawson, Dr. Paul
Partner: UNT Libraries Government Documents Department

Wetland Plant Guide for Assessing Habitat Impacts of Real-Time Salinity Management

Description: This wetland plant guide was developed to aid moist soil plant identification and to assist in the mapping of waterfowl and shorebird habitat in the Grassland Water District and surrounding wetland areas. The motivation for this habitat mapping project was a concern that real-time salinity management of wetland drainage might have long-term consequences for wildfowl habitat health--changes in wetland drawdown schedules might, over the long term, lead to increased soil salinity and other conditions unfavorable to propagation of the most desirable moist soil plants. Hence, the implementation of a program to monitor annual changes in the most common moist soil plants might serve as an index of habitat health and sustainability. Our review of the current scientific and popular literature failed to identify a good, comprehensive field guide that could be used to calibrate and verify high resolution remote sensing imagery, that we had started to use to develop maps of wetland moist soil plants in the Grassland Water District. Since completing the guide it has been used to conduct ground truthing field surveys using the California Native Plant Society methodology in 2004. Results of this survey and a previous wetland plant survey in 2003 are published in a companion LBNL publication summarizing 4 years of fieldwork to advance the science of real-time wetland salinity management.
Date: October 15, 2004
Creator: Quinn, Nigel W.T. & Feldmann, Sara A.
Partner: UNT Libraries Government Documents Department

Robust Background Subtraction with Foreground Validation for Urban Traffic Video

Description: Identifying moving objects in a video sequence is a fundamental and critical task in many computer-vision applications. Background subtraction techniques are commonly used to separate foreground moving objects from the background. Most background subtraction techniques assume a single rate of adaptation, which is inadequate for complex scenes such as a traffic intersection where objects are moving at different and varying speeds. In this paper, we propose a foreground validation algorithm that first builds a foreground mask using a slow-adapting Kalman filter, and then validates individual foreground pixels by a simple moving object model, built using both the foreground and background statistics as well as the frame difference. Ground-truth experiments with urban traffic sequences show that our proposed algorithm significantly improves upon results using only Kalman filter or frame-differencing, and outperforms other techniques based on mixture of Gaussians, median filter, and approximated media filter.
Date: January 15, 2004
Creator: Cheung, S. S. & Kamath, C
Partner: UNT Libraries Government Documents Department

High Temperature Components of Magma-Related Geothermal Systems: An Experimental and Theoretical Approach

Description: This summarizes select components of a multi-faceted study of high temperature magmatic fluid behavior in shallow, silicic, volcano-plutonic geothermal systems. This work built on a foundation provided by DOE-supported advances made in our lab in understanding the physics and chemistry of the addition of HCI and other chlorides into the high temperature regions of geothermal systems. The emphasis of this project was to produce a model of the bolatile contributions from felsic magmatic systems to geothermal systems
Date: March 15, 2004
Creator: Candela, Philip A. & Piccoli, Philip M.
Partner: UNT Libraries Government Documents Department

Catalyzed hydrogenation of nitrogen and ethylene on metal (Fe, Pt) single crystal surfaces and effects of coadsorption: A sum frequency generation vibrational spectroscopy study

Description: High-pressure catalytic reactions and associated processes, such as adsorption have been studied on a molecular level on single crystal surfaces. Sum Frequency Generation (SFG) vibrational spectroscopy together with Auger Electron Spectroscopy (AES), Temperature Programmed Desorption (TPD) and Gas Chromatography (GC) were used to investigate the nature of species on catalytic surfaces and to measure the catalytic reaction rates. Special attention has been directed at studying high-pressure reactions and in particular, ammonia synthesis in order to identify reaction intermediates and the influence of adsorbates on the surface during reaction conditions. The adsorption of gases N{sub 2}, H{sub 2}, O{sub 2} and NH{sub 3} that play a role in ammonia synthesis have been studied on the Fe(111) crystal surface by sum frequency generation vibrational spectroscopy using an integrated Ultra-High Vacuum (UHV)/high-pressure system. SFG spectra are presented for the dissociation intermediates, NH{sub 2} ({approx}3325 cm{sup -1}) and NH ({approx}3235 cm{sup -1}) under high pressure of ammonia (200 Torr) on the clean Fe(111) surface. Addition of 0.5 Torr of oxygen to 200 Torr of ammonia does not significantly change the bonding of dissociation intermediates to the surface. However, it leads to a phase change of nearly 180{sup o} between the resonant and non-resonant second order non-linear susceptibility of the surface, demonstrated by the reversal of the SFG spectral features. Heating the surface in the presence of 200 Torr ammonia and 0.5 Torr oxygen reduces the oxygen coverage, which can be seen from the SFG spectra as another relative phase change of 180{sup o}. The reduction of the oxide is also supported by Auger electron spectroscopy. The result suggests that the phase change of the spectral features could serve as a sensitive indicator of the chemical environment of the adsorbates.
Date: December 15, 2004
Creator: Westerberg, Staffan Per Gustav
Partner: UNT Libraries Government Documents Department

Molecular Biology for the Environment: an EC-US hands-on Course in Environmental Biotechnology

Description: One of the central goals of this activity is to bring together young scientists (at the late Ph.D. or early postdoctoral stages of their careers) in a forum that should result in future collaborations. The course is designed to give scientists hands-on experience in modern, up-to-date biotechnological methods at the interface between molecular biology and environmental biotechnology for the analysis of microorganisms and their activities with regard to the remediation of pollutants in the environment.
Date: February 15, 2004
Creator: Lorenzo, Victor de; Ramos, Juan Luis; Kukor, Jerome & Zylstra, Gerben J.
Partner: UNT Libraries Government Documents Department

Isotopically controlled semiconductors

Description: A review of recent research involving isotopically controlled semiconductors is presented. Studies with isotopically enriched semiconductor structures experienced a dramatic expansion at the end of the Cold War when significant quantities of enriched isotopes of elements forming semiconductors became available for worldwide collaborations. Isotopes of an element differ in nuclear mass, may have different nuclear spins and undergo different nuclear reactions. Among the latter, the capture of thermal neutrons which can lead to neutron transmutation doping, can be considered the most important one for semiconductors. Experimental and theoretical research exploiting the differences in all the properties has been conducted and will be illustrated with selected examples. Manuel Cardona, the longtime editor-in-chief of Solid State Communications has been and continues to be one of the major contributors to this field of solid state physics and it is a great pleasure to dedicate this review to him.
Date: November 15, 2004
Creator: Haller, E. E.
Partner: UNT Libraries Government Documents Department

Groundwater Flow Model of the General Separations Area Using PORFLOW

Description: The E Area PA (McDowell-Boyer et al. 2000) includes a steady-state simulation of groundwater flow in the General Separations Area as a prerequisite for saturated zone contaminant transport analyses. The groundwater flow simulations are based on the FACT code (Hamm and Aleman2000). The FACT-based GSA model was selected during preparation of the original PA to take advantage of an existing model developed for environmental restoration applications at the SRS (Flach and Harris 1997, 1999; Flach 1999). The existing GSA/FACT model was then slightly modified for PA use, as described in the PA document. FACT is a finite-element code utilizing deformed brick elements. Material properties are defined at element centers, and state variables such as hydraulic head are located at element vertices. The PORFLOW code (Analytic and Computational Research, Inc. 2000) was selected for performing saturated zone transport simulations of source zone radionuclides and their progeny. PORFLOW utilizes control volume discretization and the nodal point integration method, with all properties and state variables being defined at the center of an interior grid cell. The groundwater flow calculation includes translating the Darcy velocity field computed by FACT into a form compatible for input to PORFLOW. The FACT velocity field is defined at element vertices, whereas PORFLOW requires flux across cell faces. For the present PA, PORFLOW cell face flux is computed in a two-step process. An initial face flux is computed from FACT as an average of the normal components of Darcy velocity at the four corners. The derived flux field approximately conserves mass, but not rigorously. Thus, the flux field is subsequently perturbed to force rigorous mass conservation on a cell-by-cell basis. The undocumented process used is non-unique and can introduce significant artifacts into the final flux field.
Date: July 15, 2004
Creator: FLACH, GREGORY
Partner: UNT Libraries Government Documents Department

Measurements of sextupole decay and snapback in Tevatron dipole magnets

Description: To help optimize the performance of the Fermilab Tevatron accelerator in Collider Run II, we have undertaken a systematic study of the drift and subsequent snapback of dipole magnet harmonics. The study has mostly focused on the dynamic behavior of the normal sextupole component, b2, as measured on a sample of spare Tevatron dipoles at the Fermilab Magnet Test Facility. We measured the dependence of the decay amplitude and the snapback time on Tevatron ramp parameters and magnet operational history. A series of beam studies was also performed [1]. This paper summarizes the magnetic measurement results and concludes with proposals for an optimization of the b2 correction scheme which is derived from these measurements.
Date: July 15, 2004
Creator: al., Gueorgui V. Velev et
Partner: UNT Libraries Government Documents Department

Radioactive Material Transportation Considerations with Respect to DOE 3013 Storage Containers

Description: This paper evaluates sealed hardware that meets the requirements of DOE-STD-3013, ''Criteria for Preparing and packaging Plutonium Metals and Oxides for Long-Term Storage'' with respect to radioactive material (Type B quantity) transportation requirements. The Standard provides criteria for packaging of the plutonium materials for storage periods of at least 50 years. The standard requires the hardware to maintain integrity under both normal storage conditions and under anticipated handling conditions. To accomplish this, the standard requires that the plutonium be loaded in a minimum of two nested stainless steel sealed containers that are both tested for leak-tightness per ANSI N14.5. As such the 3013 hardware is robust. While the 3013 STD may provide appropriate storage criteria, it is not intended to provide criteria for transporting the material under the requirements of the Department of Transportation (DOT). In this evaluation, it is assumed that the activity of plutonium exceeds A1 and/or A2 curies as defined in DOT 49 CFR 173.431 and therefore must be shipped as a Type B package meeting the Nuclear Regulatory Commission (NRC) requirements of 10 CFR 71. The evaluation considers Type B shipment of plutonium in the 3013 hardware within a certified package for such contents.
Date: April 15, 2004
Creator: HENSEL, SJ
Partner: UNT Libraries Government Documents Department

Investigating the potential for long-term permeable reactive barrier (PRB) monitoring from the electrical signatures associated with the reduction in reactive iron performance

Description: The objective of this project is to quantify the ability of the electrical induced polarization (IP) method to noninvasively monitor the reduction in reactive iron performance that is known to reduce the effectiveness of the permeable reactive barrier (PRB) with time. The primary scientific goals include: (A) fundamental laboratory studies to evaluate the sensitivity of the IP method to: Fe0 total surface area Fe0 surface chemistry physical/chemical changes to the Fe0 surface resulting from oxidation and precipitation; (B) monitoring of the electrical tomographic response of the Kansas City PRB over a three-year period and assessment, via correlation with aqueous geochemical data and extracted iron cores, of whether electrical signatures associated with reduced PRB performance are resolvable in field studies; (C) optimization of a three-dimensional tomographic imaging algorithm for application to highly conductive, high electrical contrast environments as represented by a PRB.
Date: June 15, 2004
Creator: Slater, Lee
Partner: UNT Libraries Government Documents Department

Corrective Action Decision Document for Corrective Action Unit 528: Polychlorinated Biphenyls Contamination, Nevada Test Site, Nevada: Revision 0

Description: This Corrective Action Decision Document (CADD) identifies and rationalizes the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office's selection of a recommended corrective action alternative appropriate to facilitate the closure of Corrective Action Unit (CAU) 528: Polychlorinated Biphenyls (PCBs) Contamination, Nevada Test Site (NTS), Nevada, under the Federal Facility Agreement and Consent Order. Located in Area 25 of the NTS, CAU 528 consists of one Corrective Action Site (CAS): 25-27-03, Polychlorinated Biphenyls Surface Contamination. Corrective Action Unit 528 was created to address the presence of PCBs around the Test Cell C concrete pad. Corrective action investigation activities were performed from August 24, 2003, through January 8, 2004. The PCBs and total petroleum hydrocarbons-diesel range organics were identified as contaminants of concern in the surface and shallow subsurface soils in 12 areas (Areas 1 through 12) at CAS 25-27-03. Based on the review of existing data, future use, and current operations at the NTS, the following alternatives have been developed for consideration: Alternative 1 - No Further Action; Alternative 2 - Clean Closure; Alternative 3 - Closure in Place with Administrative Controls. The three corrective action alternatives were evaluated on their technical merits, focusing on performance, reliability, feasibility, and safety. Alternative 3 is the preferred corrective action for CAS 25-27-03. The selected alternative was judged to meet all requirements for the technical components evaluated for closure of the sites and additionally to minimize potential future exposure pathways to the contaminated media at CAU 528.
Date: March 15, 2004
Creator: U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office
Partner: UNT Libraries Government Documents Department

Comparative metagenomics of microbial communities

Description: The predicted proteins encoded in DNA isolated from environmental microbial community samples reveal habitat-specific metabolic demands.
Date: December 15, 2004
Creator: Tringe, Susannah Green; von Mering, Christian; Kobayashi, Arthur; Salamov, Asaf A.; Chen, Kevin; Chang, Hwai W. et al.
Partner: UNT Libraries Government Documents Department

Nonlinear Plasma Waves Excitation by Intense Ion Beams in Background Plasma

Description: Plasma neutralization of an intense ion pulse is of interest for many applications, including plasma lenses, heavy ion fusion, cosmic ray propagation, etc. An analytical electron fluid model has been developed to describe the plasma response to a propagating ion beam. The model predicts very good charge neutralization during quasi-steady-state propagation, provided the beam pulse duration {tau}{sub b} is much longer than the electron plasma period 2{pi}/{omega}{sub p}, where {omega}{sub p} = (4{pi}e{sup 2}n{sub p}/m){sup 1/2} is the electron plasma frequency and n{sub p} is the background plasma density. In the opposite limit, the beam pulse excites large-amplitude plasma waves. If the beam density is larger than the background plasma density, the plasma waves break. Theoretical predictions are compared with the results of calculations utilizing a particle-in-cell (PIC) code. The cold electron fluid results agree well with the PIC simulations for ion beam propagation through a background plasma. The reduced fluid description derived in this paper can provide an important benchmark for numerical codes and yield scaling relations for different beam and plasma parameters. The visualization of numerical simulation data shows complex collective phenomena during beam entry and exit from the plasma.
Date: April 15, 2004
Creator: Kaganovich, Igor D.; Startsev, Edward A. & Davidson, Ronald C.
Partner: UNT Libraries Government Documents Department

Excess Foundry Sand Characterization and Experimental Investigation in Controlled Low-Strength Material and Hot-Mixing Asphalt

Description: This report provides technical data regarding the reuse of excess foundry sand. The report addresses three topics: a statistically sound evaluation of the characterization of foundry sand, a laboratory investigation to qualify excess foundry sand as a major component in controlled low-strength material (CLSM), and the identification of the best methods for using foundry sand as a replacement for natural aggregates for construction purposes, specifically in asphalt paving materials. The survival analysis statistical technique was used to characterize foundry sand over a full spectrum of general chemical parameters, metallic elements, and organic compounds regarding bulk analysis and leachate characterization. Not limited to characterization and environmental impact, foundry sand was evaluated by factor analyses, which contributes to proper selection of factor and maximization of the reuse marketplace for foundry sand. Regarding the integration of foundry sand into CLSM, excavatable CLSM and structural CLSM containing different types of excess foundry sands were investigated through laboratory experiments. Foundry sand was approved to constitute a major component in CLSM. Regarding the integration of foundry sand into asphalt paving materials, the optimum asphalt content was determined for each mixture, as well as the bulk density, maximum density, asphalt absorption, and air voids at Nini, Ndes, and Nmax. It was found that foundry sands can be used as an aggregate in hot-mix asphalt production, but each sand should be evaluated individually. Foundry sands tend to lower the strength of mixtures and also may make them more susceptible to moisture damage. Finally, traditional anti-stripping additives may decrease the moisture sensitivity of a mixture containing foundry sand, but not to the level allowed by most highway agencies.
Date: October 15, 2004
Creator: Paul J. Tikalsky, Hussain U. Bahia, An Deng and Thomas Snyder
Partner: UNT Libraries Government Documents Department

Microbially Mediated Immobilization of Contaminants Through In Situ Biostimulation: Scale up of EMSP project 55267

Description: The overall goal of the proposed research is to provide an improved understanding and predictive capability of the mechanisms that allow metal-reducing bacteria to be effective in the bioremediation of redox sensitive toxic metals and radionuclides. The study is motivated by the likelihood that subsurface metal-reducing bacteria can be stimulated to effectively alter the redox state of contaminants so that they are immobilized in situ for long time periods. The work described in this proposal will advance the technological and scientific needs associated with the long-term management of the enormous inground inventories of Cr, U, Tc, and Co present at numerous DOE installations throughout the country. The objectives of our project are to (1) develop an improved understanding and predictive capability of the rates and mechanisms controlling microbially mediated reduction of toxic metals and radionuclides in heterogeneous field settings, (2) quantify the impacts of hydrological and geochemical processes on the effectiveness of indigenous microorganisms to transform and immobilize radionuclides and metals in situ, (3) provide an improved understanding of the importance of microbial consortia interactions in the bacterial immobilization of radionuclides and toxic metals, and (4) determine intrinsic bioreduction rate parameters to improve our generic predictive capability of in situ microbially mediated metal reduction. This report summarizes 3.5 y of research for a 4.5 y project.
Date: June 15, 2004
Creator: Jardine, Philip M. & Brooks, Scott C.
Partner: UNT Libraries Government Documents Department