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in subjects: "Subsurface"

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Geometrical Considerations and Nomenclature for Reflectance

Report presenting a unified approach to the specification of reflectance, in terms of both incident- and reflected- beam geometry. Nomenclature to facilitate this approach is proposed. Nomenclature for categorizing and specifying reflectance quantities for a variety of different beam configurations (both incident and reflected beams) is described, and all are defined and interrelated in terms of the bidirectional reflectance-distribution function. The conditions under which the formalism can be… more

Date: October 1977

Creator: Nicodemus, F. E.; Richmond, J. C.; Hsia, J. J.; Ginsberg, I. W. & Limperis, T.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Farm Drainage

Report discussing techniques for soil drainage, including tile-drainage and open drains.

Date: 1899

Creator: Elliott, C. G. (Charles Gleason), 1850-1926

Item Type: Pamphlet

Partner: UNT Libraries Government Documents Department

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

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.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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NNWSI [Nevada Nuclear Waste Storage Investigations] waste form testing at Argonne National Laboratory; Semiannual report, January--June 1988

The Chemical Technology Division of Argonne National Laboratory is performing experiments in support of the waste package development of the Yucca Mountain Project (formerly the Nevada Nuclear Waste Storage Investigations Project). Experiments in progress include (1) the development and performance of a durability test in unsaturated conditions, (2) studies of waste form behavior in an irradiated atmosphere, (3) studies of behavior in water vapor, and (4) studies of naturally occurring glasses … more

Date: April 1990

Creator: Bates, J. K.; Gerding, T. J.; Ebert, W. L.; Mazer, J. J. & Biwer, B. M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Seismic design of circular-section concrete-lined underground openings: Preclosure performance considerations for the Yucca Mountain Site

Yucca Mountain, the potential site of a repository for high-level radioactive waste, is situated in a region of natural and man-made seismicity. Underground openings excavated at this site must be designed for worker safety in the seismic environment anticipated for the preclosure period. This includes accesses developed for site characterization regardless of the ultimate outcome of the repository siting process. Experience with both civil and mining structures has shown that underground openi… more

Date: July 1, 1992

Creator: Richardson, A.M. & Blejwas, T.E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Three dimensional visualization breakthrough in analysis and communication of technical information for nuclear waste management

Computer graphics systems that provide interactive display and manipulation of three-dimensional data are powerful tools for the analysis and communication of technical information required for characterization and design of a geologic repository for nuclear waste. Greater understanding of site performance and repository design information is possible when performance-assessment modeling results can be visually analyzed in relation to site geologic and hydrologic information and engineering dat… more

Date: November 1, 1990

Creator: Alexander, D. H.; Cerny, B. A.; Hill, E. R.; Krupka, K. M.; Smoot, J. L.; Smith, D. R. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Use of the iterative solution method for coupled finite element and boundary element modeling; Yucca Mountain Site Characterization Project

Tunnels buried deep within the earth constitute an important class geomechanics problems. Two numerical techniques used for the analysis of geomechanics problems, the finite element method and the boundary element method, have complementary characteristics for applications to problems of this type. The usefulness of combining these two methods for use as a geomechanics analysis tool has been recognized for some time, and a number of coupling techniques have been proposed. However, not all of th… more

Date: July 1, 1993

Creator: Koteras, J.R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Equations for predicting release rates for waste packages in unsaturated tuff

Nuclear waste will be placed in the potential repository at Yucca Mountain in waste packages. Spent fuel assemblies or consolidated fuel rods and borosilicate glass in steel pour canisters will be enclosed in sealed containers. The waste package consists of the waste form, the cladding on spent fuel or the defense-waste pour canister, and the outside container. Current design calls for the waste packages to be surrounded by an air gap. Although the waste package is generally not seen as the pri… more

Date: August 1, 1990

Creator: Sadeghi, M. M.; Pigford, T. H.; Chambre, P. L. & Lee, W. W. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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V-TOUGH: An enhanced version of the TOUGH code for the thermal and hydrologic simulation of large-scale problems in nuclear waste isolation

The TOUGH code developed at Lawrence Berkeley Laboratory (LBL) is being extensively used to numerically simulate the thermal and hydrologic environment around nuclear waste packages in the unsaturated zone for the Yucca Mountain Project. At the Lawrence Livermore National Laboratory (LLNL) we have rewritten approximately 80 percent of the TOUGH code to increase its speed and incorporate new options. The geometry of many problems requires large numbers of computational elements elements in order… more

Date: November 6, 1989

Creator: Nitao, J. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Preliminary assessment of the impact of conceptual model uncertainty on site performance

The US Department of Energy is responsible for the design, construction, operation, and decommission of a site for the deep geologic disposal of high-level radioactive waste (HLW). This involves site characterization and the use of performance assessment to demonstrate compliance with regulations for HLW disposal from the US Environmental Protection Agency (EPA) and the US Nuclear Regulatory Commission. The EPA standard states that a performance assessment should consider the associated uncerta… more

Date: October 1, 1990

Creator: Gallegos, D.P.; Pohl, P.I.; Olague, N.E.; Knowlton, R.G. & Updegraff, C.D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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The underground retrievable storage (URS) high-level waste management concept

This papers presents the concept of long-term underground retrievable storage (URS) of spent reactor fuel in unsaturated rock. Emplacement would be incremental and the system is planned to be experimental and flexible. The rationale for retrievability is examined, and a technical basis for 300-year retrievability is presented. Maximum isolation is the rationale for underground as opposed to surface storage. Although the potential repository site at Yucca Mountain Nevada would be suitable for a … more

Date: February 15, 1991

Creator: Ramspott, L.D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Release and transport of gaseous C-14 from a nuclear waste repository in an unsaturated medium

The potential nuclear waste repository at Yucca Mountain is to be in partially saturated rock. Released radioactive gases such as {sup 14}CO{sub 2} could have a direct pathway to the biosphere. We study the release of {sup 14}C released as {sup 14}CO{sub 2} from partly failed nuclear waste containers by analyzing the flow of gas into and out of a container. We analyze the transport of released {sup 14}CO{sub 2} in an unsaturated, fractured, porous medium with gas-phase advection and dispersion.… more

Date: November 1, 1990

Creator: Light, W. B.; Zwahlen, E. D.; Pigford, T. H.; Chambre, P. L. & Lee, W. W. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The role of laboratory analog experiments in assessing the performance of waste package materials

There is an immediate need to begin to validate models that can be used for assessing the performance of waste package materials in an unsaturated repository environment. This paper examines available testing information and testing approaches that could support validation of models for engineering barrier system (EBS) radionuclide release. The content is presented in the context of the general methodology that has been proposed for validating performance assessment models. Available experiment… more

Date: December 31, 1990

Creator: Cunnane, J.C. & Bates, J.K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Overview of chemical modeling of nuclear waste glass dissolution

Glass dissolution takes place through metal leaching and hydration of the glass surface accompanied by development of alternation layers of varying crystallinity. The reaction which controls the long-term glass dissolution rate appears to be surface layer dissolution. This reaction is reversible because the buildup of dissolved species in solution slows the dissolution rate due to a decreased dissolution affinity. Glass dissolution rates are therefore highly dependent on silica concentrations i… more

Date: February 1, 1991

Creator: Bourcier, W. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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C-14 release and transport from a nuclear waste repository in an unsaturated medium

The release of {sup 14}C as {sup 14}CO{sub 2} from partly failed spent fuel containers has been analyzed by the flow of gases into and out of the containers. This flow of gases is driven by pressure differences, which are in turn caused by heating by the spent fuel. In this analysis, the timing and size of holes in the containers are assumed to be given. A better means of predicting the time distribution and sizes of penetrations in nuclear waste containers is needed. For the purposes of far-fi… more

Date: June 1, 1990

Creator: Light, W. B.; Zwahlen, E. D.; Pigford, T. H.; Chambre, P. L. & Lee, W. W. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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A Lagrangian reactive transport simulator with successive paths and stationary-states: Concepts, implementation and verification; Revision 1

A geochemical software package which models static, single-path kinetic water-rock interactions, EQ3/6 has been modified to incorporate successive-paths and stationary states under high Peclet number transport conditions in a Lagrangian reference frame. These modifications permit calculation of reactive transport with reasonable computational requirements. Results from the new option in EQ3/6 have been compared with analytical results for the simple HCl{endash}SiO{sub 2} system; excellent agree… more

Date: September 1, 1989

Creator: Knapp, R.B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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In situ changes in the moisture content of heated, welded tuff based on thermal neutron measurements

Thermal neutron logs were collected to monitor changes in moisture content within a welded tuff rock mass heated from a borehole containing an electrical heater which remained energized for 195 days. Thermal neutron measurements were made in sampling boreholes before, during and after heating. The results generally corroborated our conceptual understanding of hydrothermal flow as well as most of the numerical modeling conducting for this study. Conceptual models have been developed in conjuncti… more

Date: July 1, 1991

Creator: Ramirez, A. L.; Carlson, R. C. & Buscheck, T. A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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The application of vertical seismic profiling and cross-hole tomographic imaging for fracture characterization at Yucca Mountain

In order to obtain the necessary characterization for the storage of nuclear waste, much higher resolution of the features likely to affect the transport of radionuclides will be required than is normally achieved in conventional surface seismic reflection used in the exploration and characterization of petroleum and geothermal resources. Because fractures represent a significant mechanical anomaly seismic methods using are being investigated as a means to image and characterize the subsurface.… more

Date: January 1, 1990

Creator: Majer, E. L.; Peterson, J. E.; Tura, M. A. & McEvilly, T. V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Earth Sciences Division annual report 1990

This Annual Report presents summaries of selected representative research activities grouped according to the principal disciplines of the Earth Sciences Division: Reservoir Engineering and Hydrogeology, Geology and Geochemistry, and Geophysics and Geomechanics. Much of the Division`s research deals with the physical and chemical properties and processes in the earth`s crust, from the partially saturated, low-temperature near-surface environment to the high-temperature environments characterist… more

Date: June 1, 1991

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Approaches to large scale unsaturated flow in heterogeneous, stratified, and fractured geologic media

This report develops a broad review and assessment of quantitative modeling approaches and data requirements for large-scale subsurface flow in radioactive waste geologic repository. The data review includes discussions of controlled field experiments, existing contamination sites, and site-specific hydrogeologic conditions at Yucca Mountain. Local-scale constitutive models for the unsaturated hydrodynamic properties of geologic media are analyzed, with particular emphasis on the effect of stru… more

Date: August 1, 1991

Creator: Ababou, R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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

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 hig… more

Date: June 1, 1999

Creator: Carr, Jeffrey W.; Fearon, Evelyn; Haack, Joachim K.; Hoskins, Steve; Hutcheon, Ian D. & Summers, Leslie J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Formulation and computational aspects of plasticity and damage models with application to quasi-brittle materials

The response of underground structures and transportation facilities under various external loadings and environments is critical for human safety as well as environmental protection. Since quasi-brittle materials such as concrete and rock are commonly used for underground construction, the constitutive modeling of these engineering materials, including post-limit behaviors, is one of the most important aspects in safety assessment. From experimental, theoretical, and computational points of vi… more

Date: September 1, 1995

Creator: Chen, Zhen & Schreyer, Howard L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Ground penetrating radar enabled by high gain GaAs photoconductive semiconductor switches

The ability of high gain GaAs Photoconductive Semiconductor switches (PCSS) to deliver fast risetime, low jitter pulses when triggered with small laser diode arrays makes them suitable for their use in ultrawide bandwidth (UWB), impulse transmitters. This paper will summarize the state-of-the-art in high gain GaAs switches and discuss how GaAs switches are being implemented in a transmitter for detection of underground structures. The advantage of this type of semiconductor switch is demonstrat… more

Date: June 1, 1996

Creator: Loubriel, G. M.; Buttram, M. T.; Aurand, J. F. & Zutavern, F. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Remedial shielding concepts for line D and line D facilities, Los Alamos Meson Physics Facility, Los Alamos National Laboratory, Los Alamos, New Mexico: Appendix 1. Final report

This appendix contains preliminary structural assessments for tunnel sections 6(T/21), 5(21/21), 3(21/21), 2(21/21), 1(21/21), 2(21/24), 1(21/24), 3(23/23), 5(21/21)S, 4(22/22), and 5(2/8). The tunnel sections are subjected to vertical and horizontal loads estimated as 115 lbs/ft{sup 2} for each 1 ft of soil covering the structure and a horizontal load equivalent to 0.3 of the estimated cover load. Determination of shear, axial and bending stresses and associated deformations are included. Youn… more

Date: May 1, 1992

Item Type: Report

Partner: UNT Libraries Government Documents Department