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High-Temperature Fast-Flow Reactor Kinetics Studies of the Reactions of Al with Cl₂, Al with HCl, and AlCl, with Cl₂ over Wide Temperature Ranges

Description: Article on high-temperature fast-flow reactor kinetics studies of the reactions of aluminum with chlorine, aluminum with hydrogen chloride and aluminum monochloride with chlorine over wide temperature ranges.
Date: April 12, 1988
Creator: Rogowski, Donald F.; Marshall, Paul & Fontijn, A. (Arthur)
Partner: UNT College of Arts and Sciences

Laboratory studies of radionuclide migration in tuff

Description: The movement of selected radionuclides has been observed in crushed tuff, intact tuff, and fractured tuff columns. Retardation factors and dispersivities were determined from the elution profiles. Retardation factors have been compared with those predicted on the basis of batch sorption studies. This comparison forms a basis for either validating distribution coefficients or providing evidence of speciation, including colloid formation. Dispersivities measured as a function of velocity provide a means of determining the effect of sorption kinetics or mass transfer on radionuclide migration. Dispersion is also being studied in the context of scaling symmetry to develop a basis for extrapolating from the laboratory scale to the field. 21 refs., 6 figs., 2 tabs.
Date: October 1, 1989
Creator: Rundberg, R.S.; Mitchell, A.J.; Ott, M.A.; Thompson, J.L. & Triay, I.R.
Partner: UNT Libraries Government Documents Department

MCNP photon transport benchmarking calculations performed at SRP. Revision 1

Description: Monte Carlo methods have long been used at the Savannah River Laboratory (SRL) to perform criticality calculations for many different processes. To perform transport analyses (both neutron and photon) a two-dimensional infinite lattice integral transport code (GLASS) has been used. The neutron transport portion of the code has been benchmarked against other codes and experimental data. The photon transport portion of the code, which is used to calculate gamma redistribution in the event of a loss of moderator and/or coolant, had not been benchmarked against either. For this reason, the Monte Carlo code MCNP was used to benchmark the photon transport portion of the GLASS code. Preceding this, a brief description of the geometry of the Savannah River Plant`s (SRP) reactor cores and how they were modeled using MCNP will be given.
Date: 1989-06~
Creator: White, A. M.
Partner: UNT Libraries Government Documents Department

Sensitivity of SRP LOCA power limit to break size and location

Description: SRP reactors are low pressure, heavy water reactors with six external process water loops that drive the coolant into an upper plenum and then downward through the assemblies. Assembly LOCA power limits are currently set in these reactors to prevent Ledinegg flow instability (FI) in any assembly flow channel. These limits are based on a postulated break area and location. This study determined the sensitivity of the power limit to the break area and location.
Date: 1989-06~
Creator: White, A. M.; Pevey, R. E. & Smith, F. G.
Partner: UNT Libraries Government Documents Department

Brief overview of the various families of grouts and their aplications

Description: It is difficult to maintain an up-to-date overview of all the grouts presently used on the international market. Better grouts are continuously developed and more formulators are making their appearance. Consequently, it is difficult to clearly define all of the products in the industry. This topic has been the subject of numerous papers and textbooks. Most authors, however, only focus on their fields of interest: applications in geotechnical, or rehabilitation, or seepage control in civil engineering, oil or mining industry. There has been a limited transfer of technology from one field to the other because of the enormous differences in magnitude, site conditions and consequently the application techniques. The tools an engineer has are: his expertise in grouting and engineering background, equipment available or to be designed or modified to carry out a particular job, relevant data available from other sciences, and products with a variety of characteristics. This paper concentrates on product selection. The most suitable product for a particular project requires a good understanding of the general chemical and mechanical characteristics of the grout. The grouts have been classified into four categories for the purpose of this paper. There may be other methods of classification; however, this is only an attempt to help the industry with the selection of the most suitable grout for a given application. The four categories are: suspension grouts, chemical grouts, hot melts, and precipitation grouts. 1 fig.
Date: April 1, 1989
Creator: Nandts, A.
Partner: UNT Libraries Government Documents Department

Volcanic hazard studies for the Yucca Mountain project

Description: Volcanic hazard studies are ongoing to evaluate the risk of future volcanism with respect to siting of a repository for disposal of high-level radioactive waste at the Yucca Mountain site. Seven Quaternary basaltic volcanic centers are located a minimum distance of 12 km and a maximum distance of 47 km from the outer boundary of the exploration block. The conditional probability of disruption of a repository by future basaltic volcanism is bounded by the range of 10{sup {minus}8} to 10{sup {minus}10} yr{sup {minus}1}. These values are currently being reexamined based on new developments in the understanding of the evaluation of small volume, basaltic volcanic centers including: (1) Many, perhaps most, of the volcanic centers exhibit brief periods of eruptive activity separated by longer periods of inactivity. (2) The centers may be active for time spans exceeding 10{sup 5} yrs, (3) There is a decline in the volume of eruptions of the centers through time, and (4) Small volume eruptions occurred at two of the Quaternary centers during latest Pleistocene or Holocene time. We classify the basalt centers as polycyclic, and distinguish them from polygenetic volcanoes. Polycyclic volcanism is characterized by small volume, episodic eruptions of magma of uniform composition over time spans of 10{sup 3} to 10{sup 5} yrs. Magma eruption rates are low and the time between eruptions exceeds the cooling time of the magma volumes. 25 refs., 2 figs.
Date: May 1, 1989
Creator: Crowe, B.; Turrin, B.; Wells, S.; Perry, F.; McFadden, L.; Renault, C.E. et al.
Partner: UNT Libraries Government Documents Department

Repository-relevant testing applied to the Yucca Mountain Project

Description: A repository environment poses a challenge to developing a testing program because of the diverse nature of conditions that may exist at a given time during the life of the repository. A starting point is to identify whether any potential waste-water contact modes are particularly deleterious to the waste form performance, and whether any interactions between materials present in the waste package environment need to be accounted for during modeling the waste form reaction. The Unsaturated Test method in one approach that has been developed by the Yucca Mountain Project (YMP) to investigate the above issues, and a description of results that have been obtained during the testing of glass and unirradiated UO{sub 2} are the subject of this report. 10 refs., 7 figs., 4 tabs.
Date: April 1, 1989
Creator: Bates, J.K.; Gerding, T.J. & Veleckis, E.
Partner: UNT Libraries Government Documents Department

Eleventh annual Department of Energy low-level waste management conference. Volume 1: Regulatory updates, performance assessment, understanding remedial action efforts

Description: Eighteen papers are presented in this volume. The section on regulatory updates present papers on EPA, NRC, and DOE regulations. The performance assessment section presents studies on disposal facilities at ORNL, Hanford, and the Feed Materials Production Center. The remedial action section papers discuss programs and remedial action activities. Papers have been processed separately for inclusion on the data base.
Date: November 1989
Partner: UNT Libraries Government Documents Department

Eleventh annual Department of Energy low-level waste management conference. Volume 2: Low-level waste strategy and planning, decontamination and decommissioning, compliance monitoring

Description: Nineteen papers are presented in volume 2. The 11 papers in the LLW Strategy and Planning section discuss plans for disposal facilities in Texas, Pennsylvania, Hanford, the Southwest and Southeast Compacts, and others. Three papers discuss decontamination technology and activities. Environmental monitoring requirements and recommendations at LLW facilities are discussed in 5 papers. Papers have been processed separately for inclusion on the data base.
Date: November 1989
Partner: UNT Libraries Government Documents Department

[Review] [1] A Most Wonderous Babble: American Art Composers, Their Music, and the American Scene, 1950-1985. [2] Art Music in the American Society: The Condition of Art Music in the Late Twentieth Century.

Description: This article reviews the two books "A Most Wondrous Babble: American Art Composers, Their Music, and the American Scene, 1950-1985" and "Art Music in the American Society: The Condition of Art Music in the Late Twentieth Century," both by Nicholas E. Tawa and published in 1987.
Date: March 1989
Creator: McKnight, Mark
Partner: UNT Libraries

Eleventh annual Department of Energy low-level waste management conference. Volume 3: Waste characterization, waste reduction and minimization, prototype licensing application

Description: Thirteen papers are presented in volume 3. The seven papers on waste characterization discuss sampling, analysis, and certification techniques for low-level radioactive wastes. Three papers discuss US DOE waste minimization policies and regulations, Y-12 Plant`s reduction of chlorinated solvents, and C-14 removal from spent resins. The last three papers discuss the licensing studies for earth-mounded concrete bunkers for LLW disposal. Papers have been processed separately for inclusion on the data base.
Date: November 1989
Partner: UNT Libraries Government Documents Department

Waste package for Yucca Mountain repository: Strategy for regulatory compliance

Description: This document summarizes the strategy given in the Site Characterization Plan (1) for demonstrating compliance with the post closure performance objectives for the waste package and the Engineered Barrier System (EBS) contained in the Code of Federal Regulations. The strategy consists of the development of a conservative waste package design that will meet the regulatory requirements with sufficient margin for uncertainty using a multi-barrier approach that takes advantage of the unsaturated nature of the Yucca Mountain site. This strategy involves an iterative process designed to achieve compliance with the requirements for substantially complete containment and EBS release. The strategy will be implemented in such a manner that sufficient evidence will be provided for presentation to the Nuclear Regulatory Commission (NRC) so that it may make a finding that there is ``reasonable assurance`` that these performance requirements will indeed be met. In implementing the strategy, DOE recognizes four fundamental goals: (1) protect public health and safety; (2) minimize financial and other resource commitments; (3) comply with applicable laws and regulations; and (4) maintain an aggressive schedule. The strategy is intended to be a reasonable balance of these competing goals. 7 refs., 3 figs., 1 tab.
Date: February 1, 1989
Creator: Cloninger, M.; Short, D. & Stahl, D.
Partner: UNT Libraries Government Documents Department

An assessment of issues related to determination of time periods required for isolation of high level waste

Description: A commonly held perception is that disposal of spent nuclear fuel or high-level waste presents a risk of unprecedented duration. The EPA requires that projected releases of radioactivity be limited for 10,000 years after disposal with the intent that risks from the disposal repository be no greater than those from the uranium ore deposit from which the nuclear fuel was originally extracted. This study reviews issues involved in assessing compliance with the requirement. The determination of compliance is assumption dependent primarily due to uncertainties in dosimetric data, and relative availability of the radioactivity for environmental transport and eventual assimilation by humans. A conclusion of this study is that, in time, a spent fuel disposal repository such as the projected Yucca Mountain Project Facility will become less hazardous than the original ore deposit. Only the time it takes to do so is in question. Depending upon the assumptions selected, this time period could range from a few centuries to hundreds of thousands of years considering only the inherent radiotoxicities. However, if it can be assumed that the spent fuel radioactivity emplaced in a waste repository is less than 1/10 as available for human assimilation than that in a uranium ore deposit, then even under the most pessimistic set of assumptions, the EPA criteria can be considered to be complied with. 24 refs., 5 figs., 2 tabs.
Date: June 1, 1989
Creator: Cohen, J.J.; Daer, G.R.; Smith, C.F.; Vogt, D.K. & Woolfolk, S.W.
Partner: UNT Libraries Government Documents Department

The influence of penetrating gamma radiation on the reaction of simulated nuclear waste glass in tuff groundwater

Description: Static leaching experiments have been performed to determine the influence of penetrating gamma radiation on the reaction of simulated nuclear waste glass in tuff groundwater at 90{degree}C. Both the leachates and the reacted glass monoliths were analyzed to characterize the reaction. Radiation was seen to acidify the leachates, but the high bicarbonate content of the groundwater prevented the pH values from dropping below 6.4. The glass reaction tended to raise the pH. Glasses based on SRL 165 black frit and PNL 76-68 glass compositions were leached. The SRL 165 type glasses were quite durable (as measured by the elemental mass loss after constant reaction times) and were unaffected by radiation. The PNL 76-68 glasses were much less durable, with the durability decreasing (after constant reaction times) as the exposure rate was increased. The primary effect of radiation is a lowering of the leachate pH which then affects the glass leaching rate. 9 refs., 5 figs.
Date: November 1, 1989
Creator: Ebert, W.L.; Bates, J.K.; Abrajano, T.A. Jr. & Gerding, T.J.
Partner: UNT Libraries Government Documents Department

In-situ observation of the alpha/beta cristobalite transition using high voltage electron microscopy

Description: A high temperature water vapor phase is expected to persist in the vicinity of high level radioactive waste packages for several hundreds of years. The authors have begun an investigation of the structural and chemical effects of water on cristobalite because of its abundance in the near field environment. A high voltage transmission electron microscope (HVEM) investigation of bulk synthesized {alpha}-cristobalite to be used in single phase dissolution and precipitation kinetics experiments revealed the presence {beta}-cristobalite, quartz and amorphous silica, in addition to {alpha}-cristobalite. Consequently, this apparent metastable persistence of {beta}-cristobalite and amorphous silica during the synthesis of {alpha}-cristobalite was investigated using a heating stage and an environmental cell installed in the HVEM that allowed the introduction of either dry CO{sub 2} or a CO{sub 2} + H{sub 2}O vapor. Preliminary electron diffraction evidence suggests that the presence of water vapor affected the {alpha}-{beta} transition temperature. Water vapor may also be responsible for the development of an amorphous silica phase at the transition that may persist over an interval of several tens of degrees. The amorphous phase was not documented during the dry heating experiments. 20 refs., 7 figs., 5 tabs.
Date: October 1, 1989
Creator: Meike, A. & Glassley, W.
Partner: UNT Libraries Government Documents Department

Characterization of liquid-water percolation in tuffs in the unsaturated zone, Yucca Mountain, Nye County, Nevada

Description: A surface-based borehole investigation currently (1989) is being done to characterize liquid-water percolation in tuffs of Miocene age in the unsaturated zone beneath Yucca Mountain, Nye County, Nevada Active in-situ testing and passive in-situ monitoring will be used in this investigation to estimate the present-day liquid-water percolation (flux). The unsaturated zone consists of a gently dipping sequence of fine-grained, densely fractured, and mostly welded ash-flow tuffs that are interbedded with fine-grained, slightly fractured, non-welded ash-flow and ash-fall tuffs that are partly vitric and zeolitized near the water table. Primary study objectives are to define the water potential field within the unsaturated zone and to determine the in-situ bulk permeability and bulk hydrologic properties of the unsaturated tuffs. Borehole testing will be done to determine the magnitude and spatial distribution of physical and hydrologic properties of the geohydrologic units, and of their water potential fields. The study area of this investigation is restricted to that part of Yucca Mountain that immediately overlies and is within the boundaries of the perimeter drift of a US Department of Energy proposed mined, geologic, high-level radioactive-waste repository. Vertically, the study area extends from near the surface of Yucca Mountain to the underlying water table, about 500 to 750 meters below the ground surface. The average distance between the proposed repository and the underlying water table is about 205 meters.
Date: December 31, 1989
Creator: Kume, J. & Rousseau, J.P.
Partner: UNT Libraries Government Documents Department

Modeling of Zircaloy cladding degradation under repository conditions

Description: Two potential degradation mechanisms, creep and stress corrosion cracking, of Zircaloy cladding during repository storage of spent nuclear fuel have been investigated. The deformation and fracture map methodology has been used to predict maximum allowable initial storage temperatures to achieve a thousand year life without rupture as a function of spent-fuel history. A stress analysis of fuel rods has been performed. Stresses in the outer zirconium oxide layer and the inner Zircaloy tube have been predicted for typical internal pressurization, oxide layer thickness, volume expansion from formation of the oxide layer and thermal expansion coefficients of the cladding and oxide. Stress relaxation occurring in-reactor has also been taken into account. The calculations indicate that for the anticipated storage conditions investigated, the outer zirconium oxide layer is in a state of compression thus making it unlikely that stress corrosion cracking of the exterior surface will occur. 20 refs., 6 figs., 9 tabs.
Date: July 1, 1989
Creator: Santanam, L.; Raghavan, S.; Chin, B.A. & Shaw, H.
Partner: UNT Libraries Government Documents Department

Fabrication and closure development of corrosion resistant containers for Nevada`s Yucca Mountain high-level nuclear waste repository

Description: US Congress and the President have determined that the Yucca Mountain site in Nevada is to be characterized to determine its suitability for construction of the first US high-level nuclear waste repository. Work in connection with this site is carried out within the Yucca Mountain Project (YMP). Lawrence Livermore National Laboratory (LLNL) has the responsibility for designing, developing, and projecting the performance of the waste package for the permanent storage of high-level nuclear waste. Babcock & Wilcox (B&W) is involved with the YMP as a subcontractor to LLNL. B&W`s role is to recommend and demonstrate a method for fabricating the metallic waste container and a method for performing the final closure of the container after it has been filled with waste. Various fabrication and closure methods are under consideration for the production of containers. This paper presents progress to date in identifying and evaluating the candidate manufacturing processes. 2 refs., 2 figs., 4 tabs.
Date: November 1, 1989
Creator: Russell, E.W.; Nelson, T.A.; Domian, H.A.; LaCount, D.F.; Robitz, E.S. & Stein, K.O.
Partner: UNT Libraries Government Documents Department

Transverse stress effect on the critical current of internal tin and bronze process Nb{sub 3}Sn superconductors

Description: The effect of transverse stress on the critical current density, J{sub c}, has been shown to be significant in bronze process Nb{sub 3}Sn, with the onset of significant degradation at about 50 Mpa. In an applied field of 10 T, the magnitude of the effect is about seven times larger for transverse stress than for axial tensile stress. In a subsequent study, similar results were observed in another bronze process Nb{sub 3}Sn conductor made by a different manufacturer. The mechanism accounting for the transverse stress effect and its large magnitude compared with the axial tensile effect is still the subject of speculation. In an attempt to better understand the nature of the effect, The authors have undertaken a series of experiments to determine whether the transverse stress effect depends on the grain morphology of the Nb{sub 3}Sn reaction layer in the superconductor. To do this, the authors have measured the effect in an internal tin conductor with excess tin, which yields a more equiaxed Nb{sub 3}Sn grain morphology than for bronze process Nb{sub 3}Sn, where the grains are more columnar. The results for the effect of transverse compression on the J{sub c} of a round bronze process Nb{sub 3}Sn wire are given. The data are probably applicable to a wide variety of Nb{sub 3}Sn conductors for magnet engineering.
Date: December 31, 1989
Creator: Ekin, J.W.; Bray, S.L.; Danielson, P.; Smathers, D.; Sabatini, R.L. & Suenaga, M.
Partner: UNT Libraries Government Documents Department

Analytical models for C-14 transport in a partially saturated, fractured, porous media

Description: Interaction between fractures and rock matrix is considered in developing a criterion for treating fractured rock as a porous medium for the purpose of transport calculations. The value of a modified Peclet number determines the suitability of the equivalent porous medium approach. Using a porous medium mode, underground concentrations of {sup 14}CO{sub 2} are predicted for the proposed nuclear waste repository at Yucca Mountain, Nevada. Maximum concentrations near the ground surface are comparable to the USNRC limit for unrestricted areas; travel times are predicted to be hundreds to thousands of years for the assumed parameter values. 8 refs., 7 figs.
Date: February 1, 1989
Creator: Light, W. B.; Pigford, T. H.; Chambre, P. L. & Lee, W. W.-L.
Partner: UNT Libraries Government Documents Department

Physical and chemical characteristics of topographically affected airflow in an open borehole at Yucca Mountain, Nevada

Description: Borehole UZ6S, on the crest of Yucca Mountain, Nevada Test Site, has exhaled approximately 10{sup 6} m{sup 3} of gas annually during winter months for three successive years. The flow arises from thermal-topographic effects. The average composition of the exhausted gas is: N{sub 2} = 78%, O{sub 2} = 21%, Ar = 0.94%, CO{sub 2} = 0.125%, and CH{sub 4} = 0.2 ppMv. The CO{sub 2} has the following isotopic signature: {sup 14}C = 108.5 percent modern carbon (pmc), and {delta}{sup 13}C = 17.1 per mil. In the thirty-month observation period, there has been a net flux to the atmosphere of approximately 40 m{sup 3} of liquid water and 1150 kg of carbon. The gas flowing from UZ6S appears to originate in the soil and/or shallow unsaturated zone at Yucca Mountain crest. 25 refs., 6 figs., 4 tabs.
Date: December 31, 1989
Creator: Thorstenson, D.C.; Woodward, J.C.; Weeks, E.P. & Haas, H.
Partner: UNT Libraries Government Documents Department

Statistical model for grain boundary and grain volume oxidation kinetics in UO{sub 2} spent fuel

Description: This paper addresses statistical characteristics for the simplest case of grain boundary/grain volume oxidation kinetics of UO{sub 2} to U{sub 3}O{sub 7} for a fragment of a spent fuel pellet. It also presents a limited discussion of future extensions to this simple case to represent the more complex cases of oxidation kinetics in spent fuels. 17 refs., 1 fig.
Date: September 1, 1989
Creator: Stout, R.B.; Shaw, H.F. & Einziger, R.E.
Partner: UNT Libraries Government Documents Department