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Effects of Landfill Leaching on the Water Quality and Biology of a Nearby Stream, South Cairo, Greene County, New York

Description: From abstract: A 1-kilometer stream reach receiving leachate-enriched water from a small municipal landfill was studied from 1971-75 to document streamflow rates and chemical quality of the stream and ground water. The distribution of benthic invertebrates and microorganisms in the stream above the landfill was markedly different from that below it; the difference is attributed to the inflow of leachate.
Date: April 1979
Creator: Ehlke, Theodore A.
Partner: UNT Libraries Government Documents Department

Subsurface Pathway Flow and Transport Modeling for the Idaho National Engineering and Environmental Laboratory's Subsurface Disposal Area

Description: Migration of contaminants through the complex subsurface at the Idaho National Engineering and Environmental Laboratory's Subsurface Disposal Area was simulated for an ongoing Comprehensive Environmental Response, Compensation, and Liability (CERCLA) assessment. A previously existing model for simulating flow and transport through the vadose zone for this site was updated to incorporate information obtained from recent characterization activities. Given the complexity of the subsurface at this site, the simulation results were acknowledged to be uncertain. Rather than attempt parametric approaches to quantify uncertainty, it was recognized that conceptual uncertainty involving the controlling processes was likely dominant. So, the effort focused on modeling different scenarios to evaluate the impact of the conceptual uncertainty.
Date: May 10, 2002
Creator: Magnuson, S.O.
Partner: UNT Libraries Government Documents Department

Utility Locating in the DOE Environment

Description: Some advances have been made in utility locating in recent years and standards have been recently published to try and categorize the level of information known about the utility in the subsurface. At the same time some characterization about the level of effort or technology in the geophysicist approach to utility locating may be generalized. The DOE environment poses some added difficulties and this presentation covers these issues, costs and the technical approach that has been developed at the INEEL to prevent utility hits and how it fits into the generalized classification of effort.
Date: April 1, 2006
Creator: Scott, Clark & Heath, Gail
Partner: UNT Libraries Government Documents Department

Farm Drainage

Description: Report discussing techniques for soil drainage, including tile-drainage and open drains.
Date: 1899
Creator: Elliott, C. G. (Charles Gleason), 1850-1926
Partner: UNT Libraries Government Documents Department

Subsurface Pathway Flow and Transport Modeling for the Idaho National Engineering and Environmental Laboratory's Subsurface Disposal Area

Description: Migration of contaminants through the complex subsurface at the Idaho National Engineering and Environmental Laboratory's Subsurface Disposal Area was simulated for an ongoing Comprehensive Environmental Response, Compensation, and Liability (CERCLA) assessment. A previously existing model for simulating flow and transport through the vadose zone for this site was updated to incorporate information obtained from recent characterization activities. Given the complexity of the subsurface at this site, the simulation results were acknowledged to be uncertain. Rather than attempt parametric approaches to quantify uncertainty, it was recognized that conceptual uncertainty involving the controlling processes was likely dominant. So, the effort focused on modeling different scenarios to evaluate the impact of the conceptual uncertainty.
Date: August 1, 2002
Creator: Magnuson, Swen O
Partner: UNT Libraries Government Documents Department

Final Report: Large-Scale Optimization for Bayesian Inference in Complex Systems

Description: The SAGUARO (Scalable Algorithms for Groundwater Uncertainty Analysis and Robust Optimiza- tion) Project focuses on the development of scalable numerical algorithms for large-scale Bayesian inversion in complex systems that capitalize on advances in large-scale simulation-based optimiza- tion and inversion methods. Our research is directed in three complementary areas: efficient approximations of the Hessian operator, reductions in complexity of forward simulations via stochastic spectral approximations and model reduction, and employing large-scale optimization concepts to accelerate sampling. Our efforts are integrated in the context of a challenging testbed problem that considers subsurface reacting flow and transport. The MIT component of the SAGUARO Project addresses the intractability of conventional sampling methods for large-scale statistical inverse problems by devising reduced-order models that are faithful to the full-order model over a wide range of parameter values; sampling then employs the reduced model rather than the full model, resulting in very large computational savings. Results indicate little effect on the computed posterior distribution. On the other hand, in the Texas-Georgia Tech component of the project, we retain the full-order model, but exploit inverse problem structure (adjoint-based gradients and partial Hessian information of the parameter-to- observation map) to implicitly extract lower dimensional information on the posterior distribution; this greatly speeds up sampling methods, so that fewer sampling points are needed. We can think of these two approaches as "reduce then sample" and "sample then reduce." In fact, these two approaches are complementary, and can be used in conjunction with each other. Moreover, they both exploit deterministic inverse problem structure, in the form of adjoint-based gradient and Hessian information of the underlying parameter-to-observation map, to achieve their speedups.
Date: October 15, 2013
Creator: Ghattas, Omar
Partner: UNT Libraries Government Documents Department

Subsurface Behavior of Plutonium and Americium at Non-Hanford Sites and Relevance to Hanford

Description: Seven sites where Pu release to the environment has raised significant environmental concerns have been reviewed. A summary of the most significant hydrologic and geochemical features, contaminant release events and transport processes relevant to Pu migration at the seven sites is presented.
Date: February 1, 2008
Creator: Cantrell, Kirk J. & Riley, Robert G.
Partner: UNT Libraries Government Documents Department

Low Cost Open-Path Instrument for Monitoring Surface Carbon Dioxide at Sequestration Sites Phase I SBIR Final Report

Description: Public confidence in safety is a prerequisite to the success of carbon dioxide (CO2) capture and storage for any program that intends to mitigate greenhouse gas emissions. In that regard, this project addresses the security of CO2 containment by undertaking development of what is called “an open path device” to measure CO2 concentrations near the ground above a CO2 storage area.
Date: October 2, 2012
Creator: Wu, Sheng
Partner: UNT Libraries Government Documents Department

Subsurface Uranium Fate and Transport: Integrated Experiments and Modeling of Coupled Biogeochemical Mechanisms of Nanocrystalline Uraninite Oxidation by Fe(III)-(hydr)oxides - Project Final Report

Description: Subsurface bacteria including sulfate reducing bacteria (SRB) reduce soluble U(VI) to insoluble U(IV) with subsequent precipitation of UO2. We have shown that SRB reduce U(VI) to nanometer-sized UO2 particles (1-5 nm) which are both intra- and extracellular, with UO2 inside the cell likely physically shielded from subsequent oxidation processes. We evaluated the UO2 nanoparticles produced by Desulfovibrio desulfuricans G20 under growth and non-growth conditions in the presence of lactate or pyruvate and sulfate, thiosulfate, or fumarate, using ultrafiltration and HR-TEM. Results showed that a significant mass fraction of bioreduced U (35-60%) existed as a mobile phase when the initial concentration of U(VI) was 160 µM. Further experiments with different initial U(VI) concentrations (25 - 900 M) in MTM with PIPES or bicarbonate buffers indicated that aggregation of uraninite depended on the initial concentrations of U(VI) and type of buffer. It is known that under some conditions SRB-mediated UO2 nanocrystals can be reoxidized (and thus remobilized) by Fe(III)-(hydr)oxides, common constituents of soils and sediments. To elucidate the mechanism of UO2 reoxidation by Fe(III) (hydr)oxides, we studied the impact of Fe and U chelating compounds (citrate, NTA, and EDTA) on reoxidation rates. Experiments were conducted in anaerobic batch systems in PIPES buffer. Results showed EDTA significantly accelerated UO2 reoxidation with an initial rate of 9.5M day-1 for ferrihydrite. In all cases, bicarbonate increased the rate and extent of UO2 reoxidation with ferrihydrite. The highest rate of UO2 reoxidation occurred when the chelator promoted UO2 and Fe(III) (hydr)oxide dissolution as demonstrated with EDTA. When UO2 dissolution did not occur, UO2 reoxidation likely proceeded through an aqueous Fe(III) intermediate as observed for both NTA and citrate. To complement to these laboratory studies, we collected U-bearing samples from a surface seep at the Rifle field site and have measured elevated U concentrations in oxic iron-rich ...
Date: August 14, 2013
Creator: Peyton, Brent M.; Timothy, Ginn R. & Sani, Rajesh K.
Partner: UNT Libraries Government Documents Department

Sediment studies of the biological factors controlling the reduction of U(VI).

Description: Studies were conducted primarily with sediments, both in laboratory incubations and in a field experiment, with supporting studies with pure cultures. To our knowledge the sediment studies were the first on microbial U(VI) reduction in actual uranium-contaminated subsurface sediments, under conditions that mimic those found in situ. Important findings included: (1) U(VI) reduction is a biotic process in subsurface sediments. (2) U(VI) reduction can be stimulated most effectively with the addition of acetate. Although it had been speculated that microbial U(VI) reduction might be capable of this type of environmental remediation ever since the discovery of microbial U(VI) reduction, this had not been previously demonstrated under environmentally relevant conditions. (3) U(VI) is reduced concurrently with Fe(III) and prior to sulfate reduction. U(VI) and Fe(III) reduction proceeded concurrently, accompanied by a dramatic enrichment in organisms in the Geobacteraceae. Sulfate-reducing microorganisms do not appear to be important components of the microbial community reducing U(VI) in these subsurface sediments. (4) Nitrate has important influences on U(VI) reduction. Nitrate inhibits the reduction of metals until nitrate is depleted. Fe(III)-reducing microorganisms such as Geobacter metallireducens and Desulfitobacterium species can oxidize Fe(II) with the reduction of nitrate which is an important consideration because our previous studies have demonstrated that freshly precipitated Fe(III) oxides can reoxidize U(IV) to U(VI). The discovery that G. metallireducens can ''run backwards'' and oxidize U(IV) when nitrate is present reveals another mechanism preventing precipitation of U(IV) in the presence of nitrate as well as potential novel strategy for removing uranium from the subsurface after a site has been remediated. (5) Importance of understanding Fe(III) forms available for microbial reduction. Fe(III) is orders of magnitude more abundant than U(VI) as an electron acceptor to support microbial growth. It was demonstrated that poorly crystalline Fe(III) oxides and structural Fe(III) in clays are the predominant ...
Date: August 4, 2004
Creator: Lovley, derek, R.
Partner: UNT Libraries Government Documents Department

Coupling TOUGH2 with CLM3: Developing a Coupled Land Surface andSubsurface Model

Description: An understanding of the hydrologic interactions among atmosphere, land surface, and subsurface is one of the keys to understanding the water cycling system that supports life on earth. The inherent coupled processes and complex feedback structures among subsystems make such interactions difficult to simulate. In this paper, we present a model that simulates the land surface and subsurface hydrologic response to meteorological forcing. This model combines a state-of-the-art land-surface model, the NCAR Community Land Model version 3 (CLM3), with a variably saturated groundwater model, TOUGH2, through an internal interface that includes flux and state variables shared by the two submodels. Specifically, TOUGH2 uses infiltration, evaporation, and root-uptake rates, calculated by CLM3, as source/sink terms in its simulation; CLM3 uses saturation and capillary pressure profiles, calculated by TOUGH2, as state variables in its simulation. This new model, CLMT2, preserves the best aspects of both submodels: the state-of-the-art modeling capability of surface energy and hydrologic processes (including snow, runoff, freezing/melting, evapotranspiration, radiation, and biophysiological processes) from CLM3 and the more realistic physical-process-based modeling capability of subsurface hydrologic processes (including heterogeneity, three-dimensional flow, seamless combining of unsaturated and saturated zone, and water table) from TOUGH2. The preliminary simulation results show that the coupled model greatly improved the predictions of the groundwater table, evapotranspiration, and surface temperature at a real watershed, as evaluated using 18 years of observed data. The new model is also ready to be coupled with an atmospheric simulation model, to form one of the first top of the atmosphere to deep groundwater atmosphere-land-surface-subsurface models.
Date: May 19, 2006
Creator: Pan, Lehua; Jin, Jiming; Miller, Norman; Wu, Yu-Shu & Bodvarsson,Gudmundur
Partner: UNT Libraries Government Documents Department

On the Inclusion of the Interfacial Area Between Phases in the Physical and Mathematical Description of Subsurface Multiphase Flow

Description: This project has contributed to the improved understanding and precise physical description of multiphase subsurface flow by combining theoretical derivation of equations, lattice Boltzmann modeling of hydrodynamics to identify characteristics and parameters, and simplification of field-scale equations to assess the advantages and disadvantages of the complete theory.
Date: January 25, 2001
Creator: Gray, W.G.
Partner: UNT Libraries Government Documents Department

The DOE Subsurface Microbial Culture Collection (SMCC)

Description: The primary activities associated with maintenance of the Subsurface Microbial Culture Collection (SMCC) were designed to ensure that the collection served as a valuable resource to DOE-funded and other scientists, especially DOE-funded scientists associated with the NABIR Program. These activities were carried out throughout the period covered by this report and in-cluded: (1) assistance in the selection of cultures for research, (2) distribution of cultures and/or data on request, (3) incorporation of newly isolated microbial strains, (4) preservation of newly isolated strains, (5) partial characterization of newly isolated strains, (6) development and main-tenance of representative subsets of cultures, (6) screening of SMCC strains for specific charac-teristics, (7) phylogenetic characterization of SMCC strains, (8) development and maintenance of a SMCC website, (9) maintenance of the SMCC databases, (10) archiving of SMCC records, and (11) quality assurance/quality control (QA/QC) activities. We describe in the Final Technical Report our accomplishments related to these activities during the period covered by this report.
Date: May 23, 2006
Creator: Balkwill, David L.
Partner: UNT Libraries Government Documents Department

Review of Upscaling Methods for Describing Unsaturated Flow

Description: The representation of small-scale features can be a challenge when attempting to model unsaturated flow in large domains. Upscaling methods offer the possibility of reducing the amount of resolution required to adequately simulate such a problem. In this report, the various upscaling techniques that are discussed in the literature are reviewed. The following upscaling methods have been identified from the literature: (1) stochastic methods, (2) renormalization methods, and (3) volume averaging and homogenization methods; in addition, a final technique, full resolution numerical modeling, is also discussed. Each of these techniques has its advantages and disadvantages. The trade-off is a reduction in accuracy in favor of a method that is easier to employ. For practical applications, the most reasonable approach appears to be one in which any of the upscaling methods identified above maybe suitable for upscaling in regions where the variations in the parameter fields are small. For regions where the subsurface structure is more complex, only the homogenization and volume averaging methods are probably suitable. With the continual increases in computational capacity, fill-resolution numerical modeling may in many instances provide a tractable means of solving the flow problem in unsaturated systems.
Date: September 26, 2000
Creator: Wood, BD
Partner: UNT Libraries Government Documents Department

Cavity Detection and Delineation Research, Report 1: Microgravimetric and Magnetic Surveys: Medford Cave Site, Florida

Description: Partial abstract: "This report reviews the scope of a research effort initiated in 1974 at the U.S. Army Engineer Waterways Experiment Station with the objectives of (a) assessing the state of the art in geophysical cavity detection and delineation methodology and (b) developing new methods and improving or adapting old methods for application to cavity detection and delineation." This report discusses the geography, topography, site drilling tests, magnetic and microgravimetric surveys, and other information about the Medfor Cave site in Florida.
Date: March 1983
Creator: Butler, Dwain K.
Partner: UNT Libraries Government Documents Department

Seismic velocity estimation from time migration

Description: This is concerned with imaging and wave propagation in nonhomogeneous media, and includes a collection of computational techniques, such as level set methods with material transport, Dijkstra-like Hamilton-Jacobi solvers for first arrival Eikonal equations and techniques for data smoothing. The theoretical components include aspects of seismic ray theory, and the results rely on careful comparison with experiment and incorporation as input into large production-style geophysical processing codes. Producing an accurate image of the Earth's interior is a challenging aspect of oil recovery and earthquake analysis. The ultimate computational goal, which is to accurately produce a detailed interior map of the Earth's makeup on the basis of external soundings and measurements, is currently out of reach for several reasons. First, although vast amounts of data have been obtained in some regions, this has not been done uniformly, and the data contain noise and artifacts. Simply sifting through the data is a massive computational job. Second, the fundamental inverse problem, namely to deduce the local sound speeds of the earth that give rise to measured reacted signals, is exceedingly difficult: shadow zones and complex structures can make for ill-posed problems, and require vast computational resources. Nonetheless, seismic imaging is a crucial part of the oil and gas industry. Typically, one makes assumptions about the earth's substructure (such as laterally homogeneous layering), and then uses this model as input to an iterative procedure to build perturbations that more closely satisfy the measured data. Such models often break down when the material substructure is significantly complex: not surprisingly, this is often where the most interesting geological features lie. Data often come in a particular, somewhat non-physical coordinate system, known as time migration coordinates. The construction of substructure models from these data is less and less reliable as the earth becomes horizontally nonconstant. Even mild ...
Date: May 31, 2007
Creator: Cameron, Maria Kourkina
Partner: UNT Libraries Government Documents Department

Foci of Volcanoes

Description: One may assume a center of volcanic activities beneath the edifice of an active volcano, which is here called the focus of the volcano. Sometimes it may be a ''magma reservoir''. Its depth may differ with types of magma and change with time. In this paper, foci of volcanoes are discussed from the viewpoints of four items: (1) Geomagnetic changes related with volcanic activities; (2) Crustal deformations related with volcanic activities; (3) Magma transfer through volcanoes; and (4) Subsurface structure of calderas.
Date: January 1, 1974
Creator: Yokoyama, I.
Partner: UNT Libraries Government Documents Department

Subsurface structure in polished fused silica and diamond turned single crystal silicon

Description: The surface and near surface structure of glass and other optical materials is greatly influenced by the nature of the processes used to generate that surface. In high quality optics, the effects of process changes are often subtle and cannot be seen with conventional metrology. The presence of process induced damage in the near surface region is felt in a number of ways. Damage thresholds for optics subjected to high fluences are a particular problem in UV or high-powered laser systems. In high quality glass, the chemical and material composition of the outermost layer is influenced principally by the grinding, lapping and polishing processes used in fabrication. Performance in high fluence applications is often dominated by these process-induced inhomogeneities in the first few hundred nanometers of material. Each succeeding step in a process is designed to remove the damage from the previous operation. However, any force against the surface, no matter how slight will leave evidence of damage. Fabrication processes invariably create dislocations, cracks and plastic deformation between 100 nm and 500 nm below the surface. In glass polishing, the first 100 nm is comprised of material redeposited from the polishing solution. This redeposition layer is responsible for the extremely smooth surfaces that can be generated on glass. Unfortunately, this layer also conceals many flaws present in the deeper surface regions.
Date: June 1, 1999
Creator: Carr, J W; Fearon, E; Haack, J; Hoskins, S; Hutcheon, I & Summers, L
Partner: UNT Libraries Government Documents Department

The Use of Radar Methods to Determine Moisture Content in the Vadose Zone

Description: Water content is a critical parameter affecting both liquid-phase and vapor-phase contaminant transport in the vadose zone. This means that accurate estimates of in situ water content must be obtained in order to design for the appropriate handling or remediation of a contaminated region of the vadose zone. Traditional methods of sampling the subsurface by drilling and/or direct sampling are very time consuming, limited in terms of spatial coverage, and have the associated risk of contacting and increasing the size of the contaminated area. One solution is to use geophysical methods which can provide a high-resolution, non-invasive means of sampling or imaging the subsurface. The overall objective of our research, defined at the start of this project, was to advance the usefulness of radar methods (ground-based and borehole) as a means of characterizing water content in the vadose zone. We have met this objective by providing research results that can be used to (1) improve the accuracy of water content estimates from radar measurements; (2) provide estimates of the potential error in water content estimates from radar measurements; (3) improve the clarity of radar images; (4) develop large-scale models of the subsurface ''architecture'' using radar images; (5) develop ways of quantifying the spatial heterogeneity of the subsurface through analysis of radar images. We have also been able to identify the critical areas where more research is needed in order to be able to use radar methods most effectively as an accurate means of subsurface characterization.
Date: December 28, 2003
Creator: Knight, Rosemary
Partner: UNT Libraries Government Documents Department

Reuse and Subsurface Injection of Municipal Sewage Effluent: Two Case Histories

Description: Report issued by the U.S. Bureau of Mines discussing sewage disposal and reuse. As stated in the introduction, "this paper describes the renovation of municipal sewage water for industrial use, and the use of subsurface waste disposal by an industrial complex and by a city" (p. 1). This report includes tables, and illustrations.
Date: 1971
Creator: Donaldson, Erle C. & Bayazeed, Abdo F.
Partner: UNT Libraries Government Documents Department

Final Report DE-FG02-97ER62475

Description: This project began with the simple goal of trying to understand the diversity of dissimilatory metal-reducing microorganisms that might be found in subsurface environments. It ended with a sophisticated understanding not only of what microorganisms are important for metal reduction in uranium-contaminated subsurface environments, but also their physiological status during in situ uranium bioremediation. These findings have provided unprecedented insight into uranium bioremediation and the methods by which this process might be optimized. A brief summary of the major accomplishments of the project is given.
Date: March 12, 2008
Creator: Lovley, Derek, R.
Partner: UNT Libraries Government Documents Department

CLMT2 user's guide: A Coupled Model for Simulation of HydraulicProcesses from Canopy to Aquifer Version 1.0

Description: CLMT2 is designed to simulate the land-surface andsubsurface hydrologic response to meteorological forcing. This modelcombines a state-of-the-art land-surface model, the NCAR Community LandModel version 3 (CLM3), with a variably saturated groundwater model, theTOUGH2, through an internal interface that includes flux and statevariables shared by the two submodels. Specifically, TOUGH2, in itssimulation, uses infiltration, evaporation, and root-uptake rates,calculated by CLM3, as source/sink terms; CLM3, in its simulation, usessaturation and capillary pressure profiles, calculated by TOUGH2, asstate variables. This new model, CLMT2, preserves the best aspects ofboth submodels: the state-of-the-art modeling capability of surfaceenergy and hydrologic processes from CLM3 (including snow, runoff,freezing/melting, evapotranspiration, radiation, and biophysiologicalprocesses) and the more realistic physical-process-based modelingcapability of subsurface hydrologic processes from TOUGH2 (includingheterogeneity, three-dimensional flow, seamless combining of unsaturatedand saturated zone, and water table). The preliminary simulation resultsshow that the coupled model greatly improved the predictions of the watertable, evapotranspiration, and surface temperature at a real watershed,as evaluated using 18 years of observed data. The new model is also readyto be coupled with an atmospheric simulation model, representing one ofthe first models that are capable to simulate hydraulic processes fromtop of the atmosphere to deep-ground.
Date: July 26, 2006
Creator: Pan, Lehua
Partner: UNT Libraries Government Documents Department

Characterization of Microbial Communities in Subsurface Nuclear Blast Cavities of the Nevada Test Site

Description: This U.S. Department of Energy (DOE) Environmental Remediation Sciences Project (ERSP) was designed to test fundamental hypotheses concerning the existence and nature of indigenous microbial populations of Nevada Test Site subsurface nuclear test/detonation cavities. Now called Subsurface Biogeochemical Research (SBR), this program’s Exploratory Research (ER) element, which funded this research, is designed to support high risk, high potential reward projects. Here, five cavities (GASCON, CHANCELLOR, NASH, ALEMAN, and ALMENDRO) and one tunnel (U12N) were sampled using bailers or pumps. Molecular and cultivation-based techniques revealed bacterial signatures at five sites (CHANCELLOR may be lifeless). SSU rRNA gene libraries contained diverse and divergent microbial sequences affiliated with known metal- and sulfur-cycling microorganisms, organic compound degraders, microorganisms from deep mines, and bacteria involved in selenate reduction and arsenite oxidation. Close relatives of Desulforudis audaxviator, a microorganism thought to subsist in the terrestrial deep subsurface on H2 and SO42- produced by radiochemical reactions, was detected in the tunnel waters. NTS-specific media formulations were used to culture and quantify nitrate-, sulfate-, iron-reducing, fermentative, and methanogenic microorganisms. Given that redox manipulations mediated by microorganisms can impact the mobility of DOE contaminants, our results should have implications for management strategies at this and other DOE sites.
Date: September 1, 2010
Creator: Duane P. Moser, Jim Bruckner, Jen Fisher, Ken Czerwinski, Charles E. Russell, and Mavrik Zavarin
Partner: UNT Libraries Government Documents Department