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Status of LLNL granite projects

Description: The status of LLNL Projects dealing with nuclear waste disposal in granitic rocks is reviewed. This review covers work done subsequent to the June 1979 Workshop on Thermomechanical Modeling for a Hardrock Waste Repository and is prepared for the July 1980 Workshop on Thermomechanical-Hydrochemical Modeling for a Hardrock Waste Repository. Topics reviewed include laboratory determination of thermal, mechanical, and transport properties of rocks at conditions simulating a deep geologic repository, and field testing at the Climax granitic stock at the USDOE Nevada Test Site.
Date: December 31, 1980
Creator: Ramspott, L.D.
Partner: UNT Libraries Government Documents Department

Permeability testing of fractures in climax stock granite at the Nevada Test Site

Description: Permeability tests conducted in the Climax stock granitic rock mass indicate that the bulk rock permeability can be highly variable. If moderately to highly fractured zones are encountered, the permeability values may lie in the range of 10{sup -4} to 10{sup -1} darcies. If, on the other hand, only intact rock or healed fractures are encountered, the permeability is found to be less than 10{sup -9} darcies. In order to assess the thermomechanical effect on fracture permeability, discrete fractures will be packed off and tested periodically throughout the thermal cycle caused by the emplacement of spent nuclear fuel in the Climax stock.
Date: December 31, 1980
Creator: Murray, W.A.
Partner: UNT Libraries Government Documents Department

Radionuclide transport and retardation in tuff

Description: Batch measurements provide an understanding of which experimental variables are important. For example, sorption ratios vary little with particle size (and surface area); however, groundwater composition and rock composition are quite important. A general correlation has been identified between mineralogy (major phases) and degree of sorption for strontium, cesium, and barium. Although these are approximate, a more detailed analysis may be possible as more samples are studied and the data base increased. Data from crushed tuff columns indicate that, except in simple cases where sorption coefficients are relatively low, and ion-exchange equilibria not only exist but are the dominant mechanism for removal of radioisotopes from solution, the simple relation between the sorption ratio R/sub d/ (or K/sub d/) and the relative velocity of radionuclides with respect to groundwater velocity may be insufficient to permit accurate modeling of the retardation of radionuclides. Additional work on whole core columns and larger blocks of intact material is required to better understand radionuclide sorption and transport through rock.
Date: December 31, 1980
Creator: Vine, E.N.; Bayhurst, B.P.; Daniels, W.R.; DeVilliers, S.J.; Erdal, B.R.; Lawrence, F.O. et al.
Partner: UNT Libraries Government Documents Department

Thermal analysis for a spent reactor fuel storage test in granite

Description: A test is conducted in which spent fuel assemblies from an operating commercial nuclear power reactor are emplaced in the Climax granite at the US Department of Energy`s Nevada Test Site. In this generic test, 11 canisters of spent PWR fuel are emplaced vertically along with 6 electrical simulator canisters on 3 m centers, 4 m below the floor of a storage drift which is 420 m below the surface. Two adjacent parallel drifts contain electrical heaters, operated to simulate (in the vicinity of the storage drift) the temperature fields of a large repository. This test, planned for up to five years duration, uses fairly young fuel (2.5 years out of core) so that the thermal peak will occur during the time frame of the test and will not exceed the peak that would not occur until about 40 years of storage had older fuel (5 to 15 years out of core) been used. This paper describes the calculational techniques and summarizes the results of a large number of thermal calculations used in the concept, basic design and final design of the spent fuel test. The results of the preliminary calculations show the effects of spacing and spent fuel age. Either radiation or convection is sufficient to make the drifts much better thermal conductors than the rock that was removed to create them. The combination of radiation and convection causes the drift surfaces to be nearly isothermal even though the heat source is below the floor. With a nominal ventilation rate of 2 m{sup 3}/s and an ambient rock temperature of 23{sup 0}C, the maximum calculated rock temperature (near the center of the heat source) is about 100{sup 0}C while the maximum air temperature in the drift is around 40{sup 0}C. This ventilation (1 m{sup 3}/s through the main drift ...
Date: September 1, 1980
Creator: Montan, D.N.
Partner: UNT Libraries Government Documents Department

Spent LWR fuel encapsulation and dry storage demonstration

Description: In 1977 the Spent Fuel Handling and Packaging Program (SFHPP) was initiated by the Department of Energy to develop and test the capability to satisfactorily encapsulate typical spent fuel assemblies from commercial light-water nuclear power plants and to establish the suitability of one or more surface and near surface concepts for the interim dry storage of the encapsulated spent fuel assemblies. The E-MAD Facility at the Nevada Test Site, which is operated for the Department of Energy by the Advanced Energy Systems Division (AESD) of the Westinghouse Electric Corporation, was chosen as the location for this demonstration because of its extensive existing capabilities for handling highly radioactive components and because of the desirable site characteristics for the proposed storage concepts. This paper describes the remote operations related to the process steps of handling, encapsulating and subsequent dry storage of spent fuel in support of the Demonstration Program.
Date: December 31, 1980
Creator: Bahorich, R.J.; Durrill, D.C.; Cross, T.E. & Unterzuber, R.
Partner: UNT Libraries Government Documents Department

Spent fuel handling system for a geologic storage test at the Nevada Test Site

Description: The Lawrence Livermore Laboratory is conducting a test of the geologic storage of encapsulated spent commercial reactor fuel assemblies in a granitic rock at the Nevada Test Site. The test, known as the Spent Fuel Test-Climax (SFT-C), is sponsored by the US Department of Energy, Nevada Operations Office. Eleven pressurized-water-reactor spent fuel assemblies are stored retrievably for three to five years in a linear array in the Climax stock at a depth of 420 m.
Date: May 1, 1980
Creator: Duncan, J.E.; House, P.A. & Wright, G.W.
Partner: UNT Libraries Government Documents Department

Plutonium Fission in the Oklo Natural Reactor

Description: The Oklo natural reactor was discovered in 1972. Experimental evidence has indicated that the fuel source was primarily 235U with a small contribution of 7 to 9 percent from the fission of 239Pu. This article's reevaluation of data indicates that 239Pu was an important source of fuel in some areas of the reactor. A small portion of xenon and krypton released from Oklo sample 1348 appears to have originated from a source enriched in 239Pu. That fuel source may have been the core of a natural breeder reactor.
Date: August 18, 1980
Creator: Holloway, R.W.
Partner: UNT Libraries Government Documents Department

The Potential Use of Radioactive Decay Products for Dating Groundwater

Description: The accumulation in groundwater of products from the radioactive decay of elements naturally found in rocks offers a potential for measuring the time that the groundwater has been contact with the rock. This method of dating groundwater has an advantage over using decay products from the atmosphere in that the amount of decay product becomes greater with increasing age rather than less. However, different decay products accumulate at different rates and, thus, have a different potential usefulness in age determinations. The most useful decay product is helium, produced from uranium and thorium. Argon produced from potassium is marginally useful for very old water. Neon, xenon and krypton are probably not useful because they are produced in extremely small quantities. In general, the potential for error increases when a long time to produce a small quantity is required.
Date: March 20, 1980
Creator: Cornman, W.R.
Partner: UNT Libraries Government Documents Department

The Uptake of Hydrogen Fluoride by a Forest

Description: A mathematical model of hydrogen fluoride (HF) deposition and accumulation of fluoride in a Eucalyptus rostrata forest has been developed. The model is based on tree physiology and meteorological principles. The data base for the model was derived from a literature survey of the physiological characteristics of E. rostrata and similar eucalyptus species and from current knowledge of meteorological processes in plant canopies.
Date: December 18, 1980
Creator: Murphy, C.E. Jr.
Partner: UNT Libraries Government Documents Department

The specificity of plant defences

Description: This article discusses the specificity of plant defences.
Date: January 10, 1980
Creator: Dixon, R. A. & Lamb, Christopher J.
Partner: UNT College of Arts and Sciences

Test storage of spent reactor fuel in the Climax granite at the Nevada Test Site

Description: A test of retrievable dry geologic storage of spent fuel assemblies from an operating commercial nuclear reactor is underway at the Nevada Test Site. This generic test is located 420 m below the surface in the Climax granitic stock. Eleven canisters of spent fuel approximately 2.3 years out of reactor core (about 2 kW/canister thermal output) will be emplaced in a storage drift along with 6 electrical simulator canisters and their effects will be compared. Two adjacent drifts will contain electrical heaters, which will be operated to simulate within the test array the thermal field of a large repository. The test objectives, technical concepts and rationale, and details of the test are stated and discussed.
Date: February 13, 1980
Creator: Ramspott, L.D. & Ballou, L.B.
Partner: UNT Libraries Government Documents Department

Sixth workshop on geothermal reservoir engineering: Proceedings

Description: INTRODUCTION TO THE PROCEEDINGS OF THE SIXTH GEOTHERMAL RESERVOIR ENGINEERING WORKSHOP, STANFORD GEOTHERMAL PROGRAM Henry J. Ramey, Jr., and Paul Kruger Co-Principal Investigators Ian G. Donaldson Program Manager Stanford Geothermal Program The Sixth Workshop on Geothermal Reservoir Engineering convened at Stanford University on December 16, 1980. As with previous Workshops the attendance was around 100 with a significant participation from countries other than the United States (18 attendees from 6 countries). In addition, there were a number of papers from foreign contributors not able to attend. Because of the success of all the earlier workshops there was only one format change, a new scheduling of Tuesday to Thursday rather than the earlier Wednesday through Friday. This change was in general considered for the better and will be retained for the Seventh Workshop. Papers were presented on two and a half of the three days, the panel session, this year on the numerical modeling intercomparison study sponsored by the Department of Energy, being held on the second afternoon. This panel discussion is described in a separate Stanford Geothermal Program Report (SGP-TR42). This year there was a shift in subject of the papers. There was a reduction in the number of papers offered on pressure transients and well testing and an introduction of several new subjects. After overviews by Bob Gray of the Department of Energy and Jack Howard of Lawrence Berkeley Laboratory, we had papers on field development, geopressured systems, production engineering, well testing, modeling, reservoir physics, reservoir chemistry, and risk analysis. A total of 51 papers were contributed and are printed in these Proceedings. It was, however, necessary to restrict the presentations and not all papers printed were presented. Although the content of the Workshop has changed over the years, the format to date has proved to be satisfactory. The ...
Date: December 18, 1980
Creator: Ramey, H. J., Jr. & Kruger, P.
Partner: UNT Libraries Government Documents Department

Well Log Interpretation of the Cerro Prieto Field

Description: To examine how changes in rock properties affect the well log responses in a sedimentary type geothermal field, we studied the well logs from the Cerro Prieto field in Mexico. A fair amount of well logs are available for the field. Copies of the logs were obtained through the Lawrence Berkeley Laboratory.
Date: December 16, 1980
Creator: Ershaghi, I. & Ghaemian, S.
Partner: UNT Libraries Government Documents Department

Transient Steam Flow in Porous Media - Theory and Experiment

Description: The adsorption of steam in porous media, leading to a delay in steam pressure breakthrough, has been incorporated into a revised model of steam flow in a porous medium.
Date: December 16, 1980
Creator: Herkelrath, W.N. & Moench, A.F.
Partner: UNT Libraries Government Documents Department

Fissure-Block Model for Transient Pressure Analysis in Geothermal Steam Reservoirs

Description: At an earlier Stanford workshop, Moench (1978) presented a nonisothermal, radial flow, fissure-block, finite-difference model for geothermal steam reservoirs which was later used to simulate pressure buildup data for a steam well in Larderello, Italy (Moench and Neri, 1979). The model assumed the blocks to be impermeable but capable of conducting heat to the fissures which had been cooled by vaporization. In the present paper the model is revised to account for steam transport and vaporization within the blocks. This is a necessary consideration in order to accouht f o r the longevity of production wells i n The Geysers. The blocks, which may be i n i t i a l l y saturated w i t h l i q u i d water, are assumed t o have low i n t r i n s i c permeability and low p o r o s i t y relative to the fissures. Results computed with this finite-difference model are compared, for isothermal conditions, with the solutions of Boulton and Streltsova (1977). Under these conditions the model is similar to that of Kazemi (1969). When vaporization occurs in the blocks from a small amount of uniformly-distributed liquid water it is also possible to apply Boulton and Streltsova's solutions. This i s done by allowing for the apparent compressibility of the two-phase fluid mixture in the block. Comparison with Boulton and Streltsova's solutions under two-phase conditions is given in order to verify the finite-difference code. Numerical results are also presented showing pressure buildup following production with the blocks initially nearly saturated with liquid water. Effects of different thermal boundary conditions, block sizes and production times on pressure buildup curves are examined. After further refinements the model will be calibrated, using available pressure buildup data from representative wells in ...
Date: December 16, 1980
Creator: Moench, A.F. & Denlinger, R.
Partner: UNT Libraries Government Documents Department

Hydrothermal Alteration Minerals of the Geysers Steam Field, California and their Potential Use in Exploration

Description: Little information has been published on the hydrothermal alteration minerals occurring at depth in the Geysers steam field, California. Steiner (1958) reported the occurrence of wairakite from a well; McNitt (1964) identified pyrite, sericite, calcite, quartz, siderite, apatite and chlorite in cores of Franciscan graywacke and greenstone. Recently, Union Oil Geothermal Division furnished a set of well cores from the cap rock overlying the steam reservoir for geophysical studies (Lockner -e t -a l . , 1980). Cores of metagraywacke and greenstone from 4 wells were compared to unaltered Franciscan metagraywacke from surface exposures. Several previously unreported alteration minerals were found in the cored rocks, including epidote, tremolite-actinolite, prehnite and tourmaline. This note describes the observed alteration minerals and some of the factors that controlled their growth.
Date: December 16, 1980
Creator: Moore, Diane
Partner: UNT Libraries Government Documents Department

Numerical Code Comparison Project - A Necessary Step Towards Confidence in Geothermal Reservoir Simulators

Description: A necessary first step in resolving differences and in evaluating the usefulness of numerical simulators for geothermal reservoir analysis is the comparison of simulator results for a set of well-specified problems involving processes applicable in reservoir analysis. Under the direction of DOE'S Geothermal Reservoir Engineering Management Program (GREMP), a set of six test problems has been developed in an attempt to meet this need. The problem set covers a range of reservoir situations including single- and two-phase flow under 1, 2, and 3 dimensional conditions. Each problem has been test run to insure that the parameter specifications will yield workable solutions, and in several cases analytical solutions are available for comparison. Brief descriptions of the problems are given in each problem, the desired grid and time-step sizes were specified to minimize differences in results due to numerical discretization.
Date: December 16, 1980
Creator: Sorey, Michael L.
Partner: UNT Libraries Government Documents Department

Electron capture from K shells by fully stripped ions

Description: This article discusses electron capture from K shells by fully stripped ions.
Date: November 1980
Creator: Lapicki, Gregory & McDaniel, Floyd Del. (Floyd Delbert), 1942-
Partner: UNT College of Arts and Sciences

Generalizarea problemei 0:59

Description: This note extends a certain combinatorics problem of I. Tomescu.
Date: 1980
Creator: Anghel, Nicolae
Partner: UNT College of Arts and Sciences

High pressure luminescence probes in polymers

Description: High pressure luminescence has proved to be a very powerful tool for characterizing crystalline solids and liquids. Two problems involving glassy polymers are analyzed. In the first problem the excited states of azulene and its derivatives are used to probe intermolecular interactions in PMMA and PS. In the second problem the change in emission intensity with pressure from two excimer states of polyvinylcarbazole as a pure polymer and in dilute solution in polystyrene (PS), polymethylmethacrylate (PMMA) and polyisoliutylene (PIB) is studied. The relative emission from the two states depends strongly on the possibility for motion of polymer segments. The observations are related to the proximity to the glass transition.
Date: January 1, 1980
Creator: Drickamer, H.G.
Partner: UNT Libraries Government Documents Department

Full amplitude models of 15 day Cepheids

Description: Numerical models of Cepheids have been computed with a range of effective temperatures and compositions. The amplitudes increase if the helium abundance increases or if the effective temperature decreases. The latter effect is contrary to observational data. The models also exhibit velocity amplitudes which are much lower than those observed.
Date: January 1, 1980
Creator: Cogan, B.C.; Cox, A.N. & King, D.S.
Partner: UNT Libraries Government Documents Department