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Ecosystems, Biomes, and Watersheds: Definitions and Use (open access)

Ecosystems, Biomes, and Watersheds: Definitions and Use

This paper describes the meaning and applications of ecosystem and of the related terms watershed and biome. It discusses the pros and cons of all three as organizing principles for land management, and the major issues that are likely to arise in the debate over ecosystem management.
Date: July 14, 1993
Creator: Corn, M. Lynne
System: The UNT Digital Library
The Future of Remote Sensing From Space: Civilian Satellite Systems and Applications (open access)

The Future of Remote Sensing From Space: Civilian Satellite Systems and Applications

This report examines issues related to the development and operation of publicly funded U.S. and foreign civilian remote sensing systems. It also explores the military and intelligence use of data gathered by civilian satellites. In addition, the report examines the outlook for privately funded and operated remote sensing systems.
Date: July 1993
Creator: United States. Congress. Office of Technology Assessment.
System: The UNT Digital Library
Adult Literacy and New Technologies: Tools for a Lifetime (open access)

Adult Literacy and New Technologies: Tools for a Lifetime

Adult education needs are difficult to define and difficult to meet; what constitutes adequate literacy changes continually as the demands facing individuals grow more complex. This report is an attempt to identify those capabilities, along with limitations, and outline how new information technologies can be marshaled to meet the goal of a fully literate citizenry.
Date: July 1993
Creator: United States. Congress. Office of Technology Assessment.
System: The UNT Digital Library
Alternative Coca Reduction Strategies in the Andean Region (open access)

Alternative Coca Reduction Strategies in the Andean Region

This report identifies opportunities for and constraints to reducing Andean coca production through: 1) improving U.S. alternative development efforts and 2) applying biological control technology (bio-control) to eradicate illegally produced coca.
Date: July 1993
Creator: United States. Congress. Office of Technology Assessment.
System: The UNT Digital Library
Kinetics of silica-phase transitions (open access)

Kinetics of silica-phase transitions

In addition to the stable silica polymorph quartz, several metastable silica phases are present in Yucca Mountain. The conversion of these phases to quartz is accompanied by volume reduction and a decrease in the aqueous silica activity, which may destabilize clinoptilolite and mordenite. The primary reaction sequence for the silica phases is from opal or glass to disordered opal-CT, followed by ordering of the opal-CT and finally by the crystallization of quartz. The ordering of opal-CT takes place in the solid state, whereas the conversion of opal-CT takes place through dissolution-reprecipitation involving the aqueous phase. It is proposed that the rate of conversion of opal-CT to quartz is controlled by diffusion of defects out of a disordered surface layer formed on the crystallizing quartz. The reaction rates are observed to be dependent on temperature, pressure, degree of supersaturation, and pH. Rate equations selected from the literature appear to be consistent with observations at Yucca Mountain.
Date: July 1, 1993
Creator: Duffy, C.J.
System: The UNT Digital Library
SOXAL combined SO{sub x}/NO{sub x} flue gas control demonstration. Quarterly report, January--March 1993 (open access)

SOXAL combined SO{sub x}/NO{sub x} flue gas control demonstration. Quarterly report, January--March 1993

AQUATECH Systems a business unit of Allied-Signal Inc., proposes to demonstrate the technical viability and cost effectiveness of the SOXAL process a combined SO{sub x}/NO{sub x} control process on a 3 MW equivalent flue gas slip stream from Niagara Mohawk Power Corporation, Dunkirk Steam Station Boiler No. 4, a coal fired boiler. The SOXAL process combines 90+% sulfur dioxide removal from the flue gas using a sodium based scrubbing solution and regeneration of the spent scrubbing liquor using AQUATECH Systems` proprietary bipolar membrane technology. This regeneration step recovers a stream of sulfur dioxide suitable for subsequent processing to salable sulfur or sulfuric acid. Additionally 90+% control of NO{sub x} gases can be achieved in combination with conventional urea/methanol injection of NO{sub 2} gas into the duct. The SOXAL process is applicable to both utility and industrial scale boilers using either high or low sulfur coal. The SOXAL demonstration Program began September 10, 1991 and is approximately 22 months in duration. During the 6 months of scheduled operations period, expected to begin January 1992, data will be collected from the SOXAL system to define: SO{sub 2} and NO{sub x} control efficiencies; Current efficiency for the regeneration unit; Sulfate oxidation in the …
Date: July 26, 1993
Creator: unknown
System: The UNT Digital Library
Energy changes in transforming solids annual report, February 1, 1994--January 31, 1995 (open access)

Energy changes in transforming solids annual report, February 1, 1994--January 31, 1995

The recently formulated thermodynamic theory of elastic bodies prone to damage has been further developed. This formalism is based on classical thermodynamics using the local state approximation, with a significant amount of attention paid to non-isothermal processes. Certain concepts are being clarified via the use of Onsager`s reciprocal relations. Planned work includes a significant effort to develop the fundamental elements of an exact thermodynamic theory, which until now has been restricted to the one-dimensional case, and will be extended to two and three dimensions. Information is also included on publications in print, in press, and submitted since the last report (8/92).
Date: July 1, 1993
Creator: Herrmann, G. & Barnett, D.M.
System: The UNT Digital Library
Use of the iterative solution method for coupled finite element and boundary element modeling; Yucca Mountain Site Characterization Project (open access)

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 them lend themselves to efficient computational implementations for large-scale problems. This report examines a coupling technique that can form the basis for an efficient analysis tool for large scale geomechanics problems through the use of an iterative equation solver.
Date: July 1, 1993
Creator: Koteras, J.R.
System: The UNT Digital Library
Annual report to Congress, FY 1992 (open access)

Annual report to Congress, FY 1992

The Office of Civilian Radioactive Waste Management (OCRWM) is responsible for disposing of the Nation`s spent nuclear fuel from civilian nuclear power reactors and high-level radioactive waste from its defense activities in a cost-effective manner that protects the health and safety of the public and workers and the quality of the environment. To accomplish this mission OCRWM is developing a waste management system consisting of a geologic repository, a facility for monitored retrievable storage, and a system for transporting the waste. This is the ninth annual report submitted by the OCRWM to Congress. The OCRWM submits this report to inform Congress of its activities and expenditures during fiscal year 1992 (October 1, 1991 through September 30, 1992).
Date: July 1, 1993
Creator: unknown
System: The UNT Digital Library
A literature review of coupled thermal-hydrologic-mechanical-chemical processes pertinent to the proposed high-level nuclear waste repository at Yucca Mountain (open access)

A literature review of coupled thermal-hydrologic-mechanical-chemical processes pertinent to the proposed high-level nuclear waste repository at Yucca Mountain

A literature review has been conducted to determine the state of knowledge available in the modeling of coupled thermal (T), hydrologic (H), mechanical (M), and chemical (C) processes relevant to the design and/or performance of the proposed high-level waste (HLW) repository at Yucca Mountain, Nevada. The review focuses on identifying coupling mechanisms between individual processes and assessing their importance (i.e., if the coupling is either important, potentially important, or negligible). The significance of considering THMC-coupled processes lies in whether or not the processes impact the design and/or performance objectives of the repository. A review, such as reported here, is useful in identifying which coupled effects will be important, hence which coupled effects will need to be investigated by the US Nuclear Regulatory Commission in order to assess the assumptions, data, analyses, and conclusions in the design and performance assessment of a geologic reposit``. Although this work stems from regulatory interest in the design of the geologic repository, it should be emphasized that the repository design implicitly considers all of the repository performance objectives, including those associated with the time after permanent closure. The scope of this review is considered beyond previous assessments in that it attempts with the current state-of-knowledge) …
Date: July 1, 1993
Creator: Manteufel, R. D.; Ahola, M. P.; Turner, D. R. & Chowdhury, A. H.
System: The UNT Digital Library
A comparative application of the Repository Integration Program (RIP) to Total System Performance Assessment, 1991 (open access)

A comparative application of the Repository Integration Program (RIP) to Total System Performance Assessment, 1991

During Fiscal Year (FY) 1991 and FY 1992, Sandia National Laboratory and Battelle Pacific Northwest Laboratory were assigned the responsibility to generate initial Total System Performance Assessments (TSPAs) of the Yucca Mountain site. The analyses performed by these organizations (called TSPA-1991) are reported in Barnard et al(1992) and Eslinger et al. (1993). During this same time period, Golder Associates Inc. was assigned the task of generating a model capable of analyzing the total system performance of a high-level radioactive waste repository. The developed model, called Repository Integration Program (RIP), is documented in Kossik and Hachey (1993), Miller et al. (1993), and Golder Associates Inc. (1993). In FY 1993, the Civilian Radioactive Waste Management System Contractor was assigned the responsibility to plan, coordinate, and contribute to the second iteration of TSPA-2. Prior to initiating the next TSPA iteration, it was decided that it would be valuable to evaluate the applicability of RIP for use in this iteration. Therefore, analyses were conducted to compare the results generated by RIP to those reported in TSPA-1991. In particular, the aim was to generate a RIP input data set as equivalent as possible to that documented in Barnard et al. (1992) and to analyze the …
Date: July 16, 1993
Creator: unknown
System: The UNT Digital Library
Proposed algorithm for determining the delta intercept of a thermocouple psychrometer curve (open access)

Proposed algorithm for determining the delta intercept of a thermocouple psychrometer curve

The USGS Hydrologic Investigations Program is currently developing instrumentation to study the unsaturated zone at Yucca Mountain in Nevada. Surface-based boreholes up to 2,500 feet in depth will be drilled, and then instrumented in order to define the water potential field within the unsaturated zone. Thermocouple psychrometers will be used to monitor the in-situ water potential. An algorithm is proposed for simply and efficiently reducing a six wire thermocouple psychrometer voltage output curve to a single value, the delta intercept. The algorithm identifies a plateau region in the psychrometer curve and extrapolates a linear regression back to the initial start of relaxation. When properly conditioned for the measurements being made, the algorithm results in reasonable results even with incomplete or noisy psychrometer curves over a 1 to 60 bar range.
Date: July 1, 1993
Creator: Kurzmack, M.A.
System: The UNT Digital Library
Water levels in continuously monitored wells in the Yucca Mountain area, Nevada, 1985--88 (open access)

Water levels in continuously monitored wells in the Yucca Mountain area, Nevada, 1985--88

Water levels have been monitored hourly in 15 wells completed in 23 depth intervals in the Yucca Mountain area, Nevada. Water levels were monitored using pressure transducers and were recorded by data loggers. The pressure transducers were periodically calibrated by raising and lowering them in the wells. The water levels were normally measured at approximately the same time that the transducers were calibrated. Where the transducer output appeared reasonable, it was converted to water levels using the calibrations and manual water- level measurements. The amount of transducer output that was converted to water levels ranged from zero for several intervals to about 98 percent for one interval. Fourteen of the wells were completed in Tertiary volcanic rocks and one well was completed in Paleozoic carbonate rocks. Each well monitored from one to four depth intervals. Water-level fluctuation caused by barometric pressure changes and earth tides were observed.
Date: July 1, 1993
Creator: Luckey, Richard R.; Lobmeyer, David H. & Burkhardt, Douglas J.
System: The UNT Digital Library
Measured solubilities and speciations of neptunium, plutonium, and americium in a typical groundwater (J-13) from the Yucca Mountain region; Milestone report 3010-WBS 1.2.3.4.1.3.1 (open access)

Measured solubilities and speciations of neptunium, plutonium, and americium in a typical groundwater (J-13) from the Yucca Mountain region; Milestone report 3010-WBS 1.2.3.4.1.3.1

Solubility and speciation data are important in understanding aqueous radionuclide transport through the geosphere. They define the source term for transport retardation processes such as sorption and colloid formation. Solubility and speciation data are useful in verifying the validity of geochemical codes that are part of predictive transport models. Results are presented from solubility and speciation experiments of {sup 237}NpO{sub 2}{sup +}, {sup 239}Pu{sup 4+}, {sup 241}Am{sup 3+}/Nd{sup 3+}, and {sup 243}Am{sup 3+} in J-13 groundwater (from the Yucca Mountain region, Nevada, which is being investigated as a potential high-level nuclear waste disposal site) at three different temperatures (25{degree}, 60{degree}, and 90{degree}C) and pH values (5.9, 7.0, and 8.5). The solubility-controlling steady-state solids were identified and the speciation and/or oxidation states present in the supernatant solutions were determined. The neptunium solubility decreased with increasing temperature and pH. Plutonium concentrations decreased with increasing temperature and showed no trend with pH. The americium solutions showed no clear solubility trend with increasing temperature and increasing pH.
Date: July 1, 1993
Creator: Nitsche, H.; Gatti, R.C. & Standifer, E.M.
System: The UNT Digital Library
Dynamical behavior of tantalum (open access)

Dynamical behavior of tantalum

The authors have performed four dynamic impact tests on tantalum to determine its high-pressure yield and viscoelastic properties. Their experiments used compressed gas gun techniques to produce a combination of shocks, reshocks and releases over the pressure range 0--12 GPa in samples 5.0 and 7.3 mm thick. Profiles were recorded using VISAR (velocity interferometry) techniques. Elastic precursors suggest a yield strength of 0.95 GPa, which is somewhat above literature values. As with other metals, release waves do not show a perfect elastic-plastic behavior, indicating a slight Baushinger effect. Lagrangian sound velocities for singly shocked states are consistent with earlier results (about 4.5 km/sec).
Date: July 1, 1993
Creator: Furnish, M. D.; Chhabildas, L. C. & Steinberg, D. J.
System: The UNT Digital Library
Preclosure radiological safety evaluation: Exploratory Studies Facility; Yucca Mountain Site Characterization Project (open access)

Preclosure radiological safety evaluation: Exploratory Studies Facility; Yucca Mountain Site Characterization Project

A radiological safety evaluation is performed to determine the impacts of Exploratory Studies Facility (ESF) design changes on the preclosure public radiological safety for a potential nuclear waste repository at Yucca Mountain, Nevada. Although the ESF design has undergone significant modification, incorporation of the modified design requires only modest changes to the conceptual repository configuration. To the extent feasible, the results of earlier safety evaluations presented in SAND84-2641, SAND88-7061, and SAND89-7024, which were based on the original ESF configuration, are compared with the results for the modified configuration. This comparison provides an estimate of the range of analysis uncertainty. This preliminary analysis indicates that there are no Q-scenarios, which are defined as those scenarios with a net occurrence probability of greater than 10{sup {minus}6}/yr and produce a radiological dose at the 5-km controlled area boundary of greater than 0.5 rem. The analysis yielded estimates for an underground accident of a probability of 3.8 {times} 10{sup {minus}15}/yr and a dose of 1.5 rem. For a surface-initiated accident, a probability of 1.5 {times} 10{sup {minus}12}/yr and a dose of 0.6 rem was estimated.
Date: July 1, 1993
Creator: Schelling, F. J. & Smith, J. D.
System: The UNT Digital Library
Earthquake-induced water-level fluctuations at Yucca Mountain, Nevada, June 1992 (open access)

Earthquake-induced water-level fluctuations at Yucca Mountain, Nevada, June 1992

This report presents earthquake-induced water-level and fluid-pressure data for wells in the Yucca Mountain area, Nevada, during June 1992. Three earthquakes occurred which caused significant water-level and fluid-pressure responses in wells. Wells USW H-5 and USW H-6 are continuously monitored to detect short-term responses caused by earthquakes. Two wells, monitored hourly, had significant, longer-term responses in water level following the earthquakes. On June 28, 1992, a 7.5-magnitude earthquake occurred near Landers, California causing an estimated maximum water-level change of 90 centimeters in well USW H-5. Three hours later a 6.6-magnitude earthquake occurred near Big Bear Lake, California; the maximum water-level fluctuation was 20 centimeters in well USW H-5. A 5.6-magnitude earthquake occurred at Little Skull Mountain, Nevada, on June 29, approximately 23 kilometers from Yucca Mountain. The maximum estimated short-term water-level fluctuation from the Little Skull Mountain earthquake was 40 centimeters in well USW H-5. The water level in well UE-25p {number_sign}1, monitored hourly, decreased approximately 50 centimeters over 3 days following the Little Skull Mountain earthquake. The water level in UE-25p {number_sign}1 returned to pre-earthquake levels in approximately 6 months. The water level in the lower interval of well USW H-3 increased 28 centimeters following the Little Skull Mountain …
Date: July 1, 1993
Creator: O`Brien, G.M.
System: The UNT Digital Library
The appropriateness of one-dimensional Yucca Mountain hydrologic calculations; Yucca Mountain Site Characterization Project (open access)

The appropriateness of one-dimensional Yucca Mountain hydrologic calculations; Yucca Mountain Site Characterization Project

This report brings into focus the results of numerous studies that have addressed issues associated with the validity of assumptions which are used to justify reducing the dimensionality of numerical calculations of water flow through Yucca Mountain, NV. it is shown that, in many cases, one-dimensional modeling is more rigorous than previously assumed.
Date: July 1, 1993
Creator: Eaton, R. R.
System: The UNT Digital Library
Dialogs by Jerry Szymanski regarding the Yucca Mountain controversy from December, 1990 to March, 1991: Volume 3. Special report number 9, Contract number 92/94.0004 (open access)

Dialogs by Jerry Szymanski regarding the Yucca Mountain controversy from December, 1990 to March, 1991: Volume 3. Special report number 9, Contract number 92/94.0004

This report is a critical review of a US Geological Survey (USGS) paper regarding the origin of the Yucca Mountain calcite-opaline silica deposits. The report is in the form of a letter to the original authors in the USGS detailing the criticism regarding the origin of calcitic veins in the Yucca Mountain region. The USGS paper contributed most of these calcrete deposits to meteoric dissolution and precipitation mechanisms while the author presents his case for hydrothermal and magmatic origins. The paper presents strong isotopic characterization of these deposits to demonstrate a volcanic influence or source of this mineralization. Strontium, uranium, and carbon isotopes are graphed and compared from the numerous geologic and ground water samples available.
Date: July 1, 1993
Creator: unknown
System: The UNT Digital Library
Dialogs by Jerry Szymanski regarding the Yucca Mountain controversy from December, 1990 to March, 1991. Volume 1, Special report No. 9 (open access)

Dialogs by Jerry Szymanski regarding the Yucca Mountain controversy from December, 1990 to March, 1991. Volume 1, Special report No. 9

This document contains dialogs from December, 1990 to March, 1991 by Jerry Szymanski regarding the Yucca Mountain controversy. These dialogs involve the dispute about the origin of carbonate deposits at Yucca Mountain; whether pedogenic in origin or a result of episodic upwellings of ground water.
Date: July 1, 1993
Creator: Szymanski, J. & Livingston, D.E.
System: The UNT Digital Library
Development of a system of innovative insulated building blocks under energy related inventions grant. Quarterly progress report, ThermaLock Products, Inc., April 1, 1993--June 30, 1993 (open access)

Development of a system of innovative insulated building blocks under energy related inventions grant. Quarterly progress report, ThermaLock Products, Inc., April 1, 1993--June 30, 1993

Progress is briefly presented on the research pertaining to insulated building blocks. Areas covered include development of a stuffing machine, fabrication, sound tests, and earthquake test design.
Date: July 6, 1993
Creator: unknown
System: The UNT Digital Library
Trace element and REE composition of five samples of the Yucca Mountain calcite-silica deposits. Special report No. 8 (open access)

Trace element and REE composition of five samples of the Yucca Mountain calcite-silica deposits. Special report No. 8

The attached materials document the results of part of a recent effort of geochemical sampling and analysis at Yucca Mountain and nearby regions. The efforts come as a result of interest in comprehensive analyses of rare earth elements (REE), lanthanum (La) through lutecium (Lu). Several additional, non-REE analyses were obtained as well. Commercially available REE analyses have proved to be insufficiently sensitive for geochemical purposes. Dr. Roman Schmitt at the Radiation Center at Oregon State University in Corvallis was sent five samples as a trial effort. The results are very encouraging. The purpose of compiling Dr. Schmitt`s report and the other materials is to inform the sponsor of his independent observations of these results and other information that sent to him. To provide a more complete appreciation of the utility of REE analyses a copy of Dave Vaniman`s recent article is included in which he notes that REE analyses from Yucca Mountain indicate the occurrence of two distinctly different REE patterns as do several other chemical parameters of the calcite-silica deposits. Our four samples with high equivalent CaCO{sub 3} were collected from sites we believe to be spring deposits. One sample, 24D, is from southern Crater Flat which is acknowledged …
Date: July 1, 1993
Creator: Livingston, D.
System: The UNT Digital Library
Dialogs by Jerry Szymanski regarding the Yucca Mountain controversy from December, 1990 to March, 1991: Volume 2. Special report number 9, Contract number 92/94.0004 (open access)

Dialogs by Jerry Szymanski regarding the Yucca Mountain controversy from December, 1990 to March, 1991: Volume 2. Special report number 9, Contract number 92/94.0004

This report is a compilation of materials used as part of the Penrose Conference of Bodega Bay, California and the NRC/NAS panel field trip (April 23--25, 1991). The document contains extensive graphs on the hydrologic and geologic systems of the Yucca Mountain region. It outlines and diagrams hydrologic issues relative to geothermal gradients, geochemical pathways, hydraulic gradients, ground water chemistry, and ground water flow models. Specific anomalies in regards to geology or hydrology are addressed as separate issues.
Date: July 1, 1993
Creator: unknown
System: The UNT Digital Library
COMPCOAL{trademark}: A profitable process for production of a stable high-Btu fuel from Powder River Basin coal (open access)

COMPCOAL{trademark}: A profitable process for production of a stable high-Btu fuel from Powder River Basin coal

This report describes the Western Research Institute (WRI) COMPCOAL{trademark} process which is designed to produce a stable, high-Btu fuel from Powder River Basin (PRB) and other low-rank coals. The process is designed to overcome the problems of oxidation and spontaneous combustion, readsorption of moisture, and dust formation from the friable coal. PRB coal is susceptible to low-temperature oxidation and self-heating, particularly after it has been dried. This report describes a method WRI has developed to prevent self-heating of dried PRB coal. The ``accelerated aging`` not only stabilizes the dried coal, but it also increases the heating value of the COMPCOAL product. The stabilized COMPCOAL product has a heating value of 12,000 to 12,700 Btu/lb, contains 35 to 40 wt % volatiles, and is comparable to unprocessed PRB coal in self-heating and low-temperature oxidation characteristics. Importantly, the self-heating tendency can be controlled by slightly adjusting the ``aging`` step in the process.
Date: July 1, 1993
Creator: unknown
System: The UNT Digital Library