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Stratigraphic variations and secondary porosity within the Maynardville Limestone in Bear Creek Valley, Y-12 Plant, Oak Ridge, Tennessee
To evaluate groundwater and surface water contamination and migration near the Oak Ridge Y-12 plant, a Comprehensive Groundwater Monitoring Plan was developed. As part of the Maynardville exit pathways monitoring program, monitoring well clusters were ii installed perpendicular to the strike of the Maynardville Limestone, that underlies the southern part of the Y-12 Plant and Bear Creek Valley (BCV). The Maynardville Project is designed to locate potential exit pathways of groundwater, study geochemical characteristics and factors affecting the occurrence and distribution of water-bearing intervals, and provide hydrogeologic information to be used to reduce the potential impacts of contaminants entering the Maynardville Limestone.
Date:
May 1, 1995
Creator:
Goldstrand, P.M.
Object Type:
Report
System:
The UNT Digital Library
Laboratory directed research and development FY98 annual report
In 1984, Congress and the Department of Energy (DOE) established the Laboratory Directed Research and Development (LDRD) Program to enable the director of a national laboratory to foster and expedite innovative research and development (R and D) in mission areas. The Lawrence Livermore National Laboratory (LLNL) continually examines these mission areas through strategic planning and shapes the LDRD Program to meet its long-term vision. The goal of the LDRD Program is to spur development of new scientific and technical capabilities that enable LLNL to respond to the challenges within its evolving mission areas. In addition, the LDRD Program provides LLNL with the flexibility to nurture and enrich essential scientific and technical competencies and enables the Laboratory to attract the most qualified scientists and engineers. The FY98 LDRD portfolio described in this annual report has been carefully structured to continue the tradition of vigorously supporting DOE and LLNL strategic vision and evolving mission areas. The projects selected for LDRD funding undergo stringent review and selection processes, which emphasize strategic relevance and require technical peer reviews of proposals by external and internal experts. These FY98 projects emphasize the Laboratory's national security needs: stewardship of the U.S. nuclear weapons stockpile, responsibility for the …
Date:
May 1, 1999
Creator:
Al-Ayat, R & Holzrichter, J
Object Type:
Report
System:
The UNT Digital Library
M-area hazardous waste management facility groundwater monitoring and corrective-action report, First quarter 1995, Volume 3
This report, in three volumes, describes the ground water monitoring and corrective-action program at the M-Area Hazardous Waste Management Facility (HWMF) at the Savannah River Site (SRS) during the fourth quarter 1994 and first quarter 1995. Concise description of the program and considerable data documenting the monitoring and remedial activities are included in the document. Volume II includes Appendix I - water elevation and isoconcentration contour maps.
Date:
May 1, 1995
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Preparation of multilayered materials in cross-section for in situ TEM tensile deformation studies
The success of in-situ transmission electron microscopy experimentation is often dictated by proper specimen preparation. We report here a novel technique permitting the production of cross-sectioned tensile specimens of multilayered films for in-situ deformation studies. Of primary importance in the development of this technique is the production of an electron transparent micro-gauge section using focused ion beam technology. This microgauge section predetermines the position at which plastic deformation is initiated; crack nucleation, growth and failure are then subsequently observed.
Date:
May 13, 1997
Creator:
Wall, M. A.
Object Type:
Article
System:
The UNT Digital Library
A study of turbulence in an evolving stable atmospheric boundary layer using large-eddy simulation
A study is made of the effects of stable stratification on the fine-scale features of the flow in an evolving stable boundary layer (SBL). Large-eddy simulation (LES) techniques are used so that spatially and temporally varying and intermittent features of the turbulence can be resolved; traditional Reynolds-averaging approaches are not well suited to this. The LES model employs a subgrid turbulence model that allows upscale energy transfer (backscatter) and incorporates the effects of buoyancy. The afternoon, evening transition, and nighttime periods are simulated. Highly anisotropic turbulence is found in the developed SBL, with occasional periods of enhanced turbulence. Energy backscatter occurs in a fashion similar to that found in DNS, and is an important capability in LES of the SBL. Coherent structures are dominant in the SBL, as the damping of turbulent energy occurs more at the smaller, less organized scales.
Date:
May 1, 1999
Creator:
Cederwall, R & Street, R L
Object Type:
Article
System:
The UNT Digital Library
Direct flow in 10.8 GeV/nucleon Au+Au collisions measured in experiment E917 at the AGS.
Analysis of directed flow observable for protons and pions from Au+Au collisions at 10.8 GeV/nucleon from experiment E917 at the AGS is presented. Using a Fourier series expansion, the first Fourier component, {nu}{sub 1},was extracted as a function of rapidity for mid-central collisions (17-24%). Clear evidence for positive directed flow is found in the proton data, and a weak, possibly negative directed flow signal is observed for {pi}{sup +} and {pi}{sup {minus}}.
Date:
May 19, 1999
Creator:
Back, B. B.; Betts, R. R.; Britt, H. C.; Chang, J.; Chang, W. C.; Gillitzer, A. et al.
Object Type:
Article
System:
The UNT Digital Library
The beam envelope equation -- Systematic solution for a FODO lattice with space charge
Many approximate solutions for matched beam envelope functions with space charge have been developed; they generally have efforts of 2--10% for the parameters of interest and cannot be reliably improved. The new, systematic approach described here provides the K-V envelope functions to arbitrarily high accuracy as a power series in the quadrupole gradient. A useful simplification results from defining the sum and difference of the envelope radii; S = (a+b)/2 varies only slightly with distance z along the system axis, and D = (a-b)/2 contains most of the envelope oscillations. To solve the coupled equations for S and D, the quadrupole strength K(z) is turned on by replacing K with {alpha}K{sub 1} and letting {alpha} increase continuously from 0 to 1. It is found that S and D may be expanded in even and odd powers of {alpha}, respectively. Equations for the coefficients of powers of {alpha} are then solved successively by integration in z. The periodicity conditions and tune integration close the calculation. Simple low order results are typically accurate to 1% or better.
Date:
May 1, 1995
Creator:
Lee, Edward P.
Object Type:
Article
System:
The UNT Digital Library
Initial demonstration of the NRC`s capability to conduct a performance assessment for a High-Level Waste Repository
In order to better review licensing submittals for a High-Level Waste Repository, the US Nuclear Regulatory Commission staff has expanded and improved its capability to conduct performance assessments. This report documents an initial demonstration of this capability. The demonstration made use of the limited data from Yucca Mountain, Nevada to investigate a small set of scenario classes. Models of release and transport of radionuclides from a repository via the groundwater and direct release pathways provided preliminary estimates of releases to the accessible environment for a 10,000 year simulation time. Latin hypercube sampling of input parameters was used to express results as distributions and to investigate model sensitivities. This methodology demonstration should not be interpreted as an estimate of performance of the proposed repository at Yucca Mountain, Nevada. By expanding and developing the NRC staff capability to conduct such analyses, NRC would be better able to conduct an independent technical review of the US Department of Energy (DOE) licensing submittals for a high-level waste (HLW) repository. These activities were divided initially into Phase 1 and Phase 2 activities. Additional phases may follow as part of a program of iterative performance assessment at the NRC. The NRC staff conducted Phase 1 activities …
Date:
May 1, 1992
Creator:
Codell, R.; Eisenberg, N.; Fehringer, D.; Ford, W.; Margulies, T.; McCartin, T. et al.
Object Type:
Report
System:
The UNT Digital Library
A comprehensive inventory of radiological and nonradiological contaminants in waste buried or projected to be buried in the subsurface disposal area of the INEL RWMC during the years 1984-2003, Volume 3
This is the third volume of this comprehensive report of the inventory of radiological and nonradiological contaminants in waste buried or projected to be buried in the subsurface disposal area of the Idaho National Engineering Laboratory. Appendix B contains a complete printout of contaminant inventory and other information from the CIDRA Database and is presented in volumes 2 and 3 of the report.
Date:
May 1, 1995
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Report of the Federal Internetworking Requirements Panel
The Federal Internetworking Requirements Panel (FIRP) was established by the National Institute of Standards and Technology (NIST) to reassess Federal requirements for open systems networks and to recommend policy on the Government`s use of networking standards. The Panel was chartered to recommend actions which the Federal Government can take to address the short and long-term issues of interworking and convergence of networking protocols--particularly the Internet Protocol Suite (IPS) and Open Systems Interconnection (OSI) protocol suite and, when appropriate, proprietary protocols. The Panel was created at the request of the Office of Management and Budget in collaboration with the Federal Networking Council and the Federal Information Resources Management Policy Council. The Panel`s membership and charter are contained in an appendix to this report.
Date:
May 31, 1994
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Lawrence Berkeley Laboratory 1994 site environmental report
The 1994 Site Environmental Report summarizes environmental activities at Lawrence Berkeley Laboratory (LBL) for the calendar year (CY) 1994. The report strives to present environmental data in a manner that characterizes the performance and compliance status of the Laboratory`s environmental management programs when measured against regulatory standards and DOE requirements. The report also discusses significant highlight and planning efforts of these programs. The format and content of the report are consistent with the requirements of the U.S. Department of Energy (DOE) Order 5400.1, General Environmental Protection Program.
Date:
May 1, 1995
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Completion of the INEEL's WERF Incinerator Trial Burn
This paper describes the successes and challenges associated with Resource Conservation and Recovery Act (RCRA) permitting of the Idaho National Engineering and Environmental Laboratory's (INEEL) Waste Experimental Reduction Facility (WERF) hazardous and mixed waste incinerator. Topics to be discussed include facility modifications and problems, trial burn results and lessons learned in each of these areas. In addition, a number of challenges remain including completion and final issue of the RCRA Permit and implementation of all the permit requirements. Results from the trial burn demonstrated that the operating conditions and procedures will result in emissions that are satisfactorily protective of human health, the environment, and are in compliance with Federal and State regulations.
Date:
May 1, 1999
Creator:
Branter, C. K.; Conley, D. A.; Moser, D. R. & Corrigan, S. J.
Object Type:
Article
System:
The UNT Digital Library
Initial field testing definition of subsurface sealing and backfilling tests in unsaturated tuff; Yucca Mountain Site Characterization Project
This report contains an initial definition of the field tests proposed for the Yucca Mountain Project repository sealing program. The tests are intended to resolve various performance and emplacement concerns. Examples of concerns to be addressed include achieving selected hydrologic and structural requirements for seals, removing portions of the shaft liner, excavating keyways, emplacing cementitious and earthen seals, reducing the impact of fines on the hydraulic conductivity of fractures, efficient grouting of fracture zones, sealing of exploratory boreholes, and controlling the flow of water by using engineered designs. Ten discrete tests are proposed to address these and other concerns. These tests are divided into two groups: Seal component tests and performance confirmation tests. The seal component tests are thorough small-scale in situ tests, the intermediate-scale borehole seal tests, the fracture grouting tests, the surface backfill tests, and the grouted rock mass tests. The seal system tests are the seepage control tests, the backfill tests, the bulkhead test in the Calico Hills unit, the large-scale shaft seal and shaft fill tests, and the remote borehole sealing tests. The tests are proposed to be performed in six discrete areas, including welded and non-welded environments, primarily located outside the potential repository area. The …
Date:
May 1, 1993
Creator:
Fernandez, J. A.; Case, J. B. & Tyburski, J. R.
Object Type:
Report
System:
The UNT Digital Library
Progress in metal ion separation and preconcentration : an overview.
A brief historical perspective covering the most mature chemically-based metal ion separation methods is presented, as is a summary of the recommendations made in the 1987 National Research Council (NRC) report entitled ''Separation and Purification: Critical Needs and Opportunities''. A review of Progress in Metal Ion Separation and Preconcentration shows that advances are occurring in each area of need cited by the NRC. Following an explanation of the objectives and general organization of this book, the contents of each chapter are briefly summarized and some future research opportunities in metal ion separations are presented.
Date:
May 19, 1998
Creator:
Bond, A. H.
Object Type:
Article
System:
The UNT Digital Library
Plutonium and surrogate fission products in a composite ceramic waste form.
Argonne National Laboratory is developing a ceramic waste form to immobilize salt containing fission products and transuranic elements. Preliminary results have been presented for ceramic waste forms containing surrogate fission products such as cesium and the lanthanides. In this work results from scanning electron microscopy/energy dispersive spectroscopy and x-ray diffraction are presented in greater detail for ceramic waste forms containing surrogate fission products. Additionally, results for waste forms containing plutonium and surrogate fission products are presented. Most of the surrogate fission products appear to be silicates or aluminosilicates whereas the plutonium is usually found in an oxide form. There is also evidence for the presence of plutonium within the sodalite phase although the chemical speciation of the plutonium is not known.
Date:
May 19, 1999
Creator:
Esh, D. W.; Frank, S. M.; Goff, K. M.; Johnson, S. G.; Moschetti, T. L. & O'Holleran, T.
Object Type:
Article
System:
The UNT Digital Library
Location analysis and strontium-90 concentrations in deer antlers on the Hanford Site
The primary objective of this study was to examine the levels of strontium-90 ({sup 90}Sr) in deer antlers collected from near previously active reactor sites and distant from the reactor sites along that portion of the Columbia River which borders the Hanford Site. A second objective was to analyze the movements and home-ranges of mule deer residing within these areas and determine to what extent this information contributes to the observed {sup 90}Sr concentrations. {sup 90}Sr is a long-lived radionuclide (29.1 year half life) produced by fission in irradiated fuel in plutonium production reactors on the Hanford Site. It is also a major component of atmospheric fallout from weapons testing. Concentrations of radionuclides found in the developed environment onsite do not pose a health concern to humans or various wildlife routinely monitored. However, elevated levels of radionuclides in found biota may indicate routes of exposure requiring attention.
Date:
May 1, 1995
Creator:
Tiller, B L; Eberhardt, L E & Poston, T M
Object Type:
Report
System:
The UNT Digital Library
Bioavailability of mercury in East Fork Poplar Creek soils
The initial risk assessment for the East Fork Poplar Creek (EFPC) floodplain in Oak Ridge, Tennessee, a superfund site heavily contaminated with mercury, was based upon a reference dose for mercuric chloride, a soluble mercury compound not expected to be present in the floodplain, which is frequently saturated with water. Previous investigations had suggested mercury in the EFPC floodplain was less soluble and therefore less bioavailable than mercuric chloride, possibly making the results of the risk assessment unduly conservative. A bioavailability study, designed to measure the amount of mercury available for absorption in a child`s digestive tract, the most critical risk endpoint and pathway, was performed on twenty soils from the EFPC floodplain. The average percentage of mercury released during the study for the twenty soils was 5.3%, compared to 100% of the compound mercuric chloride subjected to the same conditions. Alteration of the procedure to test additional conditions possible during soil digestion did not appreciably alter the results. Therefore, use of a reference dose for mercuric chloride in the EFPC risk assessment without inclusion of a corresponding bioavailability factor may be unduly conservative.
Date:
May 1, 1995
Creator:
Barnett, M. O. & Turner, R. R.
Object Type:
Report
System:
The UNT Digital Library
Geophysical borehole logging in the unsaturated zone, Yucca Mountain, Nevada
Borehole geophysical logging for site characterization in the volcanic rocks at the proposed nuclear waste repository at Yucca Mountain, Nevada, requires data collection under rather unusual conditions. Logging tools must operate in rugose, dry holes above the water table in the unsaturated zone. Not all logging tools will operate in this environment, therefore; careful consideration must be given to selection and calibration. A sample suite of logs is presented that demonstrates correlation of geological formations from borehole to borehole, the definition of zones of altered mineralogy, and the quantitative estimates of rock properties. We show the results of an exploratory calculation of porosity and water saturation based upon density and epithermal neutron logs. Comparison of the results with a few core samples is encouraging, particularly because the logs can provide continuous data in boreholes where core samples are not available. 9 refs., 4 figs.
Date:
May 1, 1991
Creator:
Schimschal, U. & Nelson, P.H.
Object Type:
Article
System:
The UNT Digital Library
Novel bimetallic dispersed catalysts for temperature-programmed coal liquefaction. Technical progress report, January--March, 1995
Coal liquefaction involves cleavage of methylene, dimethylene and ether bridges connecting polycyclic aromatic units and the reactions of various oxygen functional groups. The selected compound for model coal liquefaction reactions are 4-(1-naphthylmethyl)bibenzyl (NMBB) and anthrone. This report describes hydrodeoxygenation of O-containing polycyclic model compounds using novel organometallic catalyst precursors and activity and selectivity of dispersed Fe catalysts from organometallic and inorganic precursors for hydrocracking of 4-(1-Naphthylmethyl) bibenzyl. For hydrodeoxygenation, model compound studies were performed using multi-ring systems, or those of comparable molecular weight, to investigate the capabilities of the dispersed catalysts. The model compounds selected include anthrone (carbonyl); dinaphthyl ether (aryl-aryl ether); xanthene (heterocyclic ether); and 2,6-di-t-butyl-4-methylphenol (hydroxyl). The catalyst precursors used were (NH{sub 4}){sub 2}MoS{sub 4}, [Ph{sub 4}P]{sub 2}[Ni(MoS{sub 4}){sub 2}] and Cp{sub 2}Co{sub 2}Mo{sub 2}(CO){sub 2}S{sub 4}. To examine what determines the activity and selectivity of Fe catalysts for hydrogenation and hydrocracking, various molecular precursors with Fe in different chemical environments have been tested in this work to help understand the influence of precursor structure and the effect of sulfur addition on the activity and selectivity of resulting Fe catalysts in model reactions of 4-(naphthylmethyl)bibenzyl. The authors have examined various precursors, including a thiocubane type cluster Cp{sub 4}Fe{sub …
Date:
May 1, 1995
Creator:
Song, C.; Kirby, S. Schmidt, E. & Schobert, H.H.
Object Type:
Report
System:
The UNT Digital Library
Gamma-ray array physics.
In this contribution I am going to discuss the development of large arrays of Compton Suppressed, High Purity Germanium (HpGe) detectors and the physics that has been, that is being, and that will be done with them. These arrays and their science have dominated low-energy nuclear structure research for the last twenty years and will continue to do so in the foreseeable future. John Sharpey Schafer played a visionary role in convincing a skeptical world that the development of these arrays would lead to a path of enlightenment. The extent to which he succeeded can be seen both through the world-wide propagation of ever more sophisticated devices, and through the world-wide propagation of his students. I, personally, would not be working in research if it were not for Johns inspirational leadership. I am eternally grateful to him. Many excellent reviews of array physics have been made in the past which can provide detailed background reading. The review by Paul Nolan, another ex-Sharpey Schafer student, is particularly comprehensive and clear.
Date:
May 25, 1999
Creator:
Lister, C. J.
Object Type:
Article
System:
The UNT Digital Library
The growth of epitaxial iron oxides on platinum (111) as studied by X-ray photoelectron diffraction, scanning tunneling microscopy, and low energy electron diffraction
Three complementary surface structure probes, x-ray photoelectron diffraction (XPD), scanning tunneling microscopy (STM), and low-energy electron diffraction (LEED) have been combined in a single instrument. This experimental system has been utilized to study the structure and growth mechanisms of iron oxide films on Pt(111); these films were formed by first depositing a single overlayer of Fe with a certain coverage in monolayers (ML`s), and then thermally oxidizing it in an oxygen atmosphere. For films up to {approximately}1 ML in thickness, a bilayer of Fe and O similar to those in FeO(111) is found to form. In agreement with prior studies, STM and LEED show this to be an incommensurate oxide film forming a lateral superlattice with short- and long-range periodicities of {approximately}3.1 {Angstrom} and {approximately}26.0 {Angstrom}. XPD in addition shows a topmost oxygen layer to be relaxed inward by -0.6 {Angstrom} compared to bulk FeO(111), and these are new structural conclusions. The oxygen stacking in the FeO(111) bilayer is dominated by one of two possible binding sites. For thicker iron oxide films from 1.25 ML to 3.0 ML, the growth mode is essentially Stranski-Krastanov: iron oxide islands form on top of the FeO(111) bilayer mentioned above. For iron oxide films …
Date:
May 1, 1995
Creator:
Kim, Y. J.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Microstructural examination of irradiated V-(4-5%)Cr-(4-5%)Ti.
Microstructural examination results are reported for two heats of V-(4-5%) Cr-(4-5%)Ti irradiated in the EBR-II X530 experiment to 4.5 dpa at {approximately}400 C to provide an understanding of the microstructural evolution that may be associated with degradation of mechanical properties. Fine precipitates were observed in high density intermixed with small defect clusters for all conditions examined following the irradiation. The irradiation-induced precipitation does not appear to be affected by preirradiation heat treatment at 950-1125 C. There was no evidence for a significant density of large (diameter >10 nm) dislocation loops or network dislocations. Analytical investigations successfully demonstrated that the precipitates were enriched in titanium, depleted in vanadium and contained no nitrogen. These results are discussed in terms of future alloy development options.
Date:
May 4, 1998
Creator:
Gelles, D. S.
Object Type:
Article
System:
The UNT Digital Library
A technical basis to relax the dew point specification for the environment in the vapor space in DWPF canisters
This memorandum establishes the technical basis to conclude that relaxing, from 0 C to 20 C, the dew point specification for the atmosphere in the vapor space (free volume) of a DWPF canister will not provide an environment that will cause significant amounts of corrosion induced degradation of the canister wall. The conclusion is based on engineering analysis, experience and review of the corrosion literature. The basic assumptions underlying the conclusion are: (1) the canister was fabricated from Type 304L stainless steel; (2) the corrosion behavior of the canister material, including base metal, fusion zones and heat effected zones, is typified by literature data for, and industrial experience with, 300 series austenitic stainless steels; and (3) the glass-metal crevices created during the pouring operation will not alter the basic corrosion resistance of the steel although such crevices might serve as sites for the initiation of minor amounts of corrosion on the canister wall.
Date:
May 1, 1995
Creator:
Louthan, M. R. Jr.
Object Type:
Report
System:
The UNT Digital Library
Aqueous biphasic systems for metal separations : a microcalorimetric analysis of polymer/salt interactions.
Certain radionuclide ions (e.g., TcO{sub 4}{sup 16}) exhibit unusually strong Affinities toward the polymer-rich phase in aqueous biphase systems generated by combinations of salt solutions with polymers such as poly(ethylene glycol) (PEG) and poly(propylene glycol) (PPG). Thus, aqueous polymer phases could potentially be used to selectively extract these ions during pretreatment of radioactive tank wastes at Hanford. To help develop a fundamental understanding of the interactions between various ions and polymers in aqueous solution, interaction enthalpies between sodium perrhenate and a random copolymer of PEG and PPG (UCON-50) were measured by microcalorimetric titration. An entropy compensation effect was observed in this system in which changes in enthalpic interactions were balanced by entropy changes such that the interaction free energy remained constant and approximately equal to zero.
Date:
May 3, 1999
Creator:
Chaiko, D. J.; Hatton, T. A. & Zaslavsky, B.
Object Type:
Article
System:
The UNT Digital Library