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A brief review of bacterial transport in natural porous media

Description: This report reviews advances in the descriptions of microbial transport processes. The advances can often be translated into technological advances for solute transport, with potential applicability to a number of subsurface concerns related to solutes. The processes involved in microbial transport include physically controlled processes, chemically controlled processes, and biologically controlled processes. The physical processes involved in the transport of microbes include advection, diffusion, dispersion, straining, filtration, and exclusion. Biomass removal by chemical reactions has received less attention, and included electrostatic attraction and hydrophobic sorption. In addition, microbiologic processes affecting the fate and transport of microbes in the subsurface include growth and decay; motility and chemotaxis; biological adhesion; and predation. Interdependencies among these processes arise through coupling, e.g., as multiscale mixing in heterogeneous environments affects nutrient availability (growth) and filtration velocities (attachment).
Date: December 1, 1995
Creator: Ginn, T.R.
Partner: UNT Libraries Government Documents Department

Particle filtration: An analysis using the method of volume averaging

Description: The process of filtration of non-charged, submicron particles is analyzed using the method of volume averaging. The particle continuity equation is represented in terms of the first correction to the Smoluchowski equation that takes into account particle inertia effects for small Stokes numbers. This leads to a cellular efficiency that contains a minimum in the efficiency as a function of the particle size, and this allows us to identify the most penetrating particle size. Comparison of the theory with results from Brownian dynamics indicates that the first correction to the Smoluchowski equation gives reasonable results in terms of both the cellular efficiency and the most penetrating particle size. However, the results for larger particles clearly indicate the need to extend the Smoluchowski equation to include higher order corrections. Comparison of the theory with laboratory experiments, in the absence of adjustable parameters, provides interesting agreement for particle diameters that are equal to or less than the diameter of the most penetrating particle.
Date: December 1, 1994
Creator: Quintard, M. & Whitaker, S.
Partner: UNT Libraries Government Documents Department

Gradient-Drive Diffusion of Multi-Atom Molecules Through Macromolecules and Membranes: LDRD 96-0021 Close-Out Report

Description: The goals of this Laboratory Directed Research and Development (LDRD) effort were to develop and prototype a new molecular simulation method and companion parallel algorithm able to model diffusion of multi-atom molecules through macromolecules under conditions of a chemical potential gradient. At the start of the project no such method existed, thus many important industrial and technological materials problems where gradient driven diffusion of multi-atom molecules is the predominant phenomenon were beyond the reach of molecular simulation (e.g. diffusion in polymers, a fundamental problem underlying polymer degradation in aging weapons).
Date: December 1, 1998
Creator: Ford, D.M.; Heffelfinger, G.S.; Martin, M.G. & Thompson, A.
Partner: UNT Libraries Government Documents Department

Underground Test Area Subproject Phase I Data Analysis Task. Volume V - Transport Parameter and Source Term Data Documentation Package

Description: Volume V of the documentation for the Phase I Data Analysis Task performed in support of the current Regional Flow Model, Transport Model, and Risk Assessment for the Nevada Test Site Underground Test Area Subproject contains the transport parameter and source term data. Because of the size and complexity of the model area, a considerable quantity of data was collected and analyzed in support of the modeling efforts. The data analysis task was consequently broken into eight subtasks, and descriptions of each subtask's activities are contained in one of the eight volumes that comprise the Phase I Data Analysis Documentation.
Date: December 1, 1996
Partner: UNT Libraries Government Documents Department

Baseline risk assessment of ground water contamination at the uranium mill tailings site near Lakeview, Oregon. Revision 1

Description: Surface cleanup at the Uranium Mill Tailings Remedial Action (UMTRA) Project site near Lakeview, Oregon was completed in 1989. The Ground Water Project evaluates the nature and extent of ground water contamination that resulted from the uranium ore processing activities. The Ground Water Project is in its beginning stages. Human health may be at risk from exposure to ground water contaminated by uranium ore processing. Exposure could occur by drinking water pumped out of a hypothetical well drilled in the contaminated areas. Ecological risks to plants or animals may result from exposure to surface water and sediment that have received contaminated ground water. A risk assessment describes a source of contamination, how that contamination reaches people and the environment, the amount of contamination to which people or the ecological environment may be exposed, and the health or ecological effects that could result from that exposure. This risk assessment is a site-specific document that will be used to evaluate current and potential future impacts to the public and the environment from exposure to contaminated ground water. The results of this evaluation and further site characterization will determine whether any action is needed to protect human health or the ecological environment.
Date: December 1, 1995
Partner: UNT Libraries Government Documents Department

Inspector General audit report on Transportation Safeguards Division courier work schedules and escort vehicle replacements

Description: The Office of Inspector General`s (OIG) April 1995 report found that couriers received too much overtime and incurred too much unproductive time. This finding occurred because the Transportation Safeguards Division (TSD) employed a traditional work schedule that did not meet the demands of the job. The report recommended implementing an alternative work schedule that corresponded more closely to the couriers` actual work requirements. Management agreed to conduct a comparative analysis of work schedules to evaluate potential savings. The objectives of this audit were to (1) follow up on actions taken as a result of the OIG`s previous report, (2) determine if courier work schedules are cost effective, and (3) determine the cost effectiveness of escort vehicle replacements. The authors recommend: (1) implementing an alternative work schedule for courier which would achieve savings in overtime and unproductive time, while efficiently and cost effectively fulfilling TSD`s mission; (2) reexamining and adjusting the staffing level of each courier section in relation to the workload requirements in the area; and (3) discontinuing payment for travel time between courier lodging and temporary duty stations. The Albuquerque Operations Office agreed with the auditor`s findings and recommendations.
Date: December 1, 1998
Partner: UNT Libraries Government Documents Department

Plasma transport near the separatrix of a magnetic island

Description: The simplest non-trivial model of transport across a magnetic island chain in the presence of collisionless streaming along the magnetic field is solved by a Wiener-Hopf procedure. The solution found is valid provided the boundary layers about the island separatrix is narrow compared to the island width. The result demonstrates that when this assumption is satisfied the flattened profile region is reduced by the boundary layer width. The calculation is similar to the recent work by Fitzpatrick but is carried out in the collisionless, rather than the collisional, limit of parallel transport, and determines the plasma parameters on the separatrix self-consistently.
Date: December 1, 1996
Creator: Hazeltine, R.D.; Helander, P. & Catto, P.J.
Partner: UNT Libraries Government Documents Department

Environmental health-risk assessment for tritium releases from the National Tritium Labeling Facility (NTLF) at Lawrence Berkeley Laboratory

Description: This report is a health risk assessment that addresses continuous releases of tritium to the environment from the National Tritium Labeling Facility (NTLF) at the Lawrence Berkeley Laboratory (LBL). The NTLF contributes approximately 95% of all tritium releases from LBL. Transport and transformation models were used to determine the movement of tritium releases from the NRLF to the air, surface water, soils, and plants and to determine the subsequent doses to humans. These models were calibrated against environmental measurements of tritium levels in the vicinity of the NTLF and in the surrounding community. Risk levels were determined for human populations in each of these zones. Risk levels to both individuals and populations were calculated. In this report population risks and individual risks were calculated for three types of diseases--cancer, heritable genetic effects, and developmental and reproductive effects.
Date: December 1, 1994
Creator: McKone, T.E. & Brand, K.P.
Partner: UNT Libraries Government Documents Department

Ground water flow velocity in the bank of the Columbia River, Hanford, Washington

Description: To properly characterize the transport of contaminants from the sediments beneath the Hanford Site into the Columbia River, a suite of In Situ Permeable Flow Sensors was deployed to accurately characterize the hydrologic regime in the banks of the river. The three dimensional flow velocity was recorded on an hourly basis from mid May to mid July, 1994 and for one week in September. The first data collection interval coincided with the seasonal high water level in the river while the second interval reflected conditions during relatively low seasonal river stage. Two flow sensors located approximately 50 feet from the river recorded flow directions which correlated very well with river stage, both on seasonal and diurnal time scales. During time intervals characterized by falling river stage, the flow sensors recorded flow toward the river while flow away from the river was recorded during times of rising river stage. The flow sensor near the river in the Hanford Formation recorded a component of flow oriented vertically downward, probably reflecting the details of the hydrostratigraphy in close proximity to the probe. The flow sensor near the river in the Ringold Formation recorded an upward component of flow which dominated the horizontal components most of the time. The upward flow in the Ringold probably reflects regional groundwater flow into the river. The magnitudes of the flow velocities recorded by the flow sensors were lower than expected, probably as a result of drilling induced disturbance of the hydraulic properties of the sediments around the probes. The probes were installed with resonant sonic drilling which may have compacted the sediments immediately surrounding the probes, thereby reducing the hydraulic conductivity adjacent to the probes and diverting the groundwater flow away from the sensors.
Date: December 1, 1995
Creator: Ballard, S.
Partner: UNT Libraries Government Documents Department

Improved atmospheric transport for risk assessment

Description: This is the final report of a two-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). To effectively respond to airborne chemical and biological warfare (CBW) attacks in urban settings, one must understand the vector of the threat, i.e., where is the effluent going and when will it get there. These answers are needed both in real time (who should be evacuated?) and afterwards (where should the cleanup be focused?). Certainly, advanced multiscale models are essential to this task. No model has value, however, until it is normalized and validated by measured data. Experience in atmospheric transport has demonstrated that the quality of model estimations is tightly coupled to the fidelity of the data and the effectiveness of its assimilation. The authors have started to quantify the improvement of accuracy of atmospheric transport and dispersion models that follows from enhanced remote sensing of meteorological parameters. The proper use of remote sensing data requires sophisticated assimilation techniques into advanced models, so the whole project emphasizes the synergy of the newest techniques for remote sensing observation, data analysis, data assimilation, and dynamic modeling. This work quantified the value of various levels of data for improving effluent tracking and prediction, and allows tradeoffs between the cost of data acquisition and its impact on accuracy.
Date: December 1, 1998
Creator: Cooper, D. & Kao, J.
Partner: UNT Libraries Government Documents Department

Core flow-through apparatus: letter report documenting testing phase

Description: As part of the task of developing conceptual, physical and chemical, and performance models of the dynamics of water and dissolved and colloidal radionuclide constituents in the near-field, measurements of flow and transport properties of repository rocks and other near- field components are required. An apparatus has been fabricated that will be used to collect pertinent flow and transport data at temperatures expected in the near-field. Description of the core-flow apparatus (CFA) and preliminary testing results are included in this letter report. The apparatus was designed to study the flow of radionuclide-bearing solutions through fractured or unfractured cylindrical samples of rock and other competent materials (e.g. concrete). Because near-field transport was the goal, the CFA was designed to be operated at elevated temperatures.
Date: December 1, 1993
Creator: Viani, B.E. & Martin, S.
Partner: UNT Libraries Government Documents Department

Nonlinear dynamics and plasma transport

Description: This progress report reports work done on a program in nonlinear dynamical aspects of plasma turbulence and transport funded by DOE from 1992-1995. The purpose of this program has been to promote the utilization of recent pathbreaking developments in nonlinear science in plasma turbulence and transport and to fully utilize the scientific expertise of Russian fusion and plasma community in collaboration with our group to address outstanding fusion theory problems. In the work reported in our progress report, we have studied simple models which are motivated by observation on actual fusion devices. The models focus on the important physical processes without incorporating the complexity of the geometry of real devices. We have also studied linear stability problems which incorporated important physics issues related to geometry involving closed field lines and open field lines. This allows for a deeper analysis and understanding of the system both analytically and numerically. The strong collaboration between the Russian visitors and the US participants has led to a fruitful and strong research program that taps the complementary analytic and numerical capabilities of the two groups. Over the years several distinguished Russian visitors have interacted with various members of the group and set up collaborative work which forms a significant part of proposed research. Dr. Galeev, Director of the Space Research Institute of Moscow and Dr. Novakovskii from the Kurchatov Institute are two such ongoing collaborations. 21 refs.
Date: December 1, 1995
Creator: Liu, C.S.; Sagdeev, R.; Antonsen, T.; Drake, J.; Hassma, A. & Guzdar, P.N.
Partner: UNT Libraries Government Documents Department

Recent upgrades and enhancements of the FEM3A model

Description: In 1984, the US Army Edgewood Research, Development and Engineering Center began to fund Lawrence Livermore National Laboratory to further develop FEM3, a fully three-dimensional heavy-gas dispersion model, as a research tool for studying the atmospheric transport and diffusion of certain chemical systems. As a result, a significantly improved version of the model, called FEM3A, was delivered to ERDEC in 1988. During the past few years, two more major improvements have been developed and tested. They are: improved mass conservation for treating dispersion scenarios with large density variations, and the addition of an advanced turbulence submodel based on the k-{var_epsilon} transport equations. These enhancements have resulted in substantial improvements in the dispersion simulations of heavy-gases and can greatly extend the range of applicability of the model, including the ability to treat problems with large density variations and dispersion scenarios of much greater complexities. Documented in this report are the new features and some of the improvements obtained with the new model.
Date: December 1, 1994
Creator: Chan, S.T.
Partner: UNT Libraries Government Documents Department

Quality Assurance Plan for the Upper East Fork Poplar Creek Characterization Area, Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

Description: This quality assurance plan summarizes requirements for conducting work on the Upper East 9 Fork Poplar Creek (UEFPC) Characterization Area (CA). The reader is referred to the Expanded Task Work Agreement for Upper East Fork Poplar Creek Characterization Area, Remedial Investigation/Feasibility Study (RI/FS) for details regarding the activities, roles, and responsibilities summarized here. UEFPC is designated a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) site and thus requires a remedial investigation (RI) and a feasibility study (FS). The RI objectives are to evaluate the nature and extent of known and suspected contaminates, to provide data to perform baseline ecological and human health risk assessments, and to support development and evaluation of remedial alternatives for the FS,. Existing data will be used as much as possible. Additional sampling may be required to fill data gaps. The goal of the RI is to prioritize the major sources of contaminants to exit pathways and to understand their characteristics for risk characterization and development of remedial alternatives. The FS objectives are to investigate technologies and develop and evaluate alternatives based on 2031 CERCLA guidance.
Date: December 1, 1996
Partner: UNT Libraries Government Documents Department

Urban airshed modeling of air quality impacts of alternative transportation fuel use in Los Angeles and Atlanta

Description: The main objective of NREL in supporting this study is to determine the relative air quality impact of the use of compressed natural gas (CNG) as an alternative transportation fuel when compared to low Reid vapor pressure (RVP) gasoline and reformulated gasoline (RFG). A table lists the criteria, air toxic, and greenhouse gas pollutants for which emissions were estimated for the alternative fuel scenarios. Air quality impacts were then estimated by performing photochemical modeling of the alternative fuel scenarios using the Urban Airshed Model Version 6.21 and the Carbon Bond Mechanism Version IV (CBM-IV) (Geary et al., 1988) Using this model, the authors examined the formation and transport of ozone under alternative fuel strategies for motor vehicle transportation sources for the year 2007. Photochemical modeling was performed for modeling domains in Los Angeles, California, and Atlanta, Georgia.
Date: December 1, 1997
Partner: UNT Libraries Government Documents Department

Beam dynamics activities at the Thomas Jefferson National Accelerator Facility (Jefferson Lab)

Description: The Thomas Jefferson National Accelerator Facility (Jefferson Lab) has been funded by the US Navy to build an infra-red FEL driven by an energy-recovering compact SRF-based linear accelerator. The machine is to produce a 1 kW IR photon beam. The Jefferson Lab Accelerator Division is presently engaged in detailed design and beam dynamics studies for the driver accelerator. Principle beam dynamics and beam transport considerations include: (1) generation and transport of a high-quality, high-current, space-charge dominated beam; (2) the impact of coherent synchrotron radiation (CSR) during beam recirculation transport; (3) low-loss transport of a large momentum spread, high-current beam; (4) beam break up (BBU) instabilities in the recirculating accelerator; (5) impedance policing of transport system components; and (6) RF drive system control during energy recovery and FEL operation.
Date: December 1, 1997
Creator: Douglas, D.R.
Partner: UNT Libraries Government Documents Department

Radionuclide transport through engineered barrier system alteration products

Description: The primary rationale for studying the transport behavior of radionuclides through the Engineered Barrier system / Near Field Environment (EBS/NFE) is to ascertain whether the material properties of the introduced and altered host rock can significantly affect the transport of radionuclides from the waste container to the far field. The intent of this report is to present data and modeling results that can be used to assess the importance of canister corrosion products and cementitious materials to transport of radionuclides to the far field.
Date: December 1, 1997
Creator: Viani, B.E.; Torretto, P.C. & Matzen, S.L.
Partner: UNT Libraries Government Documents Department

Risk assessment for the off-site transportation of high-level waste for the U.S. Department of Energy waste management programmatic environmental impact statement

Description: This report describes the human health risk assessment conducted for the transportation of high-level waste (HLW) in support of the US Department of Energy Waste Management Programmatic Environmental Impact Statement (WM PEIS). The assessment considers risks to collective populations and individuals under both routine and accident transportation conditions for truck and rail shipment modes. The report discusses the scope of the HLW transportation assessment, describes the analytical methods used for the assessment, defines the alternatives considered in the WM PEIS, and details important assessment assumptions. Results are reported for five alternatives. In addition, to aid in the understanding and interpretation of the results, specific areas of uncertainty are described, with an emphasis on how the uncertainties may affect comparisons of the alternatives.
Date: December 1, 1996
Creator: Monette, F.A.; Biwer, B.M.; LePoire, D.J. & Chen, S.Y.
Partner: UNT Libraries Government Documents Department

Gas treatment of Cr(VI)-contaminated sediment samples from the North 60`s pits of the chemical waste landfill

Description: Twenty sediment samples were collected at depths ranging from 5 to 100 ft (1.5 to 30 m) beneath a metal-contaminated plating-waste site and extensively characterized for Cr(VI) content and environmental availability. Three samples were selected for treatment with diluted gas mixtures with the objective of converting Cr(VI) to Cr(III), which is relatively nontoxic and immobile. These tests were designed to provide information needed to evaluate the potential application of gas injection as an in situ remediation technique. Gas treatment was performed in small columns (4.9-cm ID, 6.4- to 13.9-cm long) using 100 ppm ({mu}L L{sup -1}) H{sub 2}S or ethylene mixtures in N{sub 2}. Treatment progress during the tests involving H{sub 2}S was assessed by monitoring the breakthrough of H{sub 2}S. Evaluation of H{sub 2}S treatment efficacy included (1) water-leaching of treated and untreated columns for ten days, (2) repetitive extraction of treated and untreated subsamples by water, 0.01 M phosphate (pH 7) or 6 M HCl solutions, and (3) Cr K-edge X-ray absorption near-edge structure (XANES) spectroscopy of treated and untreated subsamples. Results of the water-leaching studies showed that the H{sub 2}S treatment decreased Cr(VI) levels in the column effluent by 90% to nearly 100%. Repetitive extractions by water and phosphate solutions echoed these results, and the extraction by HCl released only 35-40% as much Cr in the treated as in the untreated samples. Analysis by XANES spectroscopy showed that a substantial portion of the Cr in the samples remained as Cr(VI) after treatment, even though it was not available to the water and phosphate extracting solutions. These results suggest that this residual Cr(VI) is present in low solubility phases such as PbCrO{sub 4} or sequestered in unreacted grain interiors under impermeable coatings formed during H{sub 2}S treatment. However, this fraction is essentially immobile and thus unavailable to the ...
Date: December 1, 1997
Creator: Thornton, E.C. & Amonette, J.E.
Partner: UNT Libraries Government Documents Department

Sampling results, DNAPL monitoring well GW-729, Oak Ridge Y-12 Plant, Oak Ridge, Tennessee. Annual report

Description: This document, Sampling Results, DNAPL Monitoring Well G W-729, Third Quarter FY 1995 through Third Quarter FY 1996, was performed under Work Breakdown Structure 1.4.12.1.1.02 (Activity Data Sheet 2312, `Bear Creek Valley`). This document provides the Environmental Restoration Program with groundwater concentrations for nonradionuclides in the vicinity of the Y-12 Burial Grounds. These data can be used to determine reference concentrations for intermediate and deep groundwater systems.
Date: December 1, 1996
Creator: Drier, R.B. & Caldanaro, A.J.
Partner: UNT Libraries Government Documents Department

Natural convection heat transfer within horizontal spent nuclear fuel assemblies

Description: Natural convection heat transfer is experimentally investigated in an enclosed horizontal rod bundle, which characterizes a spent nuclear fuel assembly during dry storage and/or transport conditions. The basic test section consists of a square array of sixty-four stainless steel tubular heaters enclosed within a water-cooled rectangular copper heat exchanger. The heaters are supplied with a uniform power generation per unit length while the surrounding enclosure is maintained at a uniform temperature. The test section resides within a vacuum/pressure chamber in order to subject the assembly to a range of pressure statepoints and various backfill gases. The objective of this experimental study is to obtain convection correlations which can be used in order to easily incorporate convective effects into analytical models of horizontal spent fuel systems, and also to investigate the physical nature of natural convection in enclosed horizontal rod bundles in general. The resulting data consist of: (1) measured temperatures within the assembly as a function of power, pressure, and backfill gas; (2) the relative radiative contribution for the range of observed temperatures; (3) correlations of convective Nusselt number and Rayleigh number for the rod bundle as a whole; and (4) correlations of convective Nusselt number as a function of Rayleigh number for individual rods within the array.
Date: December 1, 1995
Creator: Canaan, R.E.
Partner: UNT Libraries Government Documents Department

Generalized chloride mass balance: Forward and inverse solutions for one-dimensional tracer convection under transient flux

Description: Forward and inverse solutions are provided for analysis of inert tracer profiles resulting from one-dimensional convective transport under fluxes which vary with time and space separately. The developments are displayed as an extension of conventional chloride mass balance (CMB) techniques to account for transient as well as space-dependent water fluxes. The conventional chloride mass balance has been used over two decades to estimate recharge over large time scales in arid environments. In this mass balance approach, the chloride concentration in the pore water, originating from atmospheric fallout, is inversely proportional to the flux of water through the sediments. The CMB method is especially applicable to arid and semi-arid regions where evapotranspirative enrichment of the pore water produces a distinct chloride profile in the unsaturated zone. The solutions presented allow incorporation of transient fluxes and boundary conditions in CMB analysis, and allow analysis of tracer profile data which is not constant with depth below extraction zone in terms of a rational water transport model. A closed-form inverse solution is derived which shows uniqueness of model parameter and boundary condition (including paleoprecipitation) estimation, for the specified flow model. Recent expressions of the conventional chloride mass balance technique are derived from the general model presented here; the conventional CMB is shown to be fully compatible with this transient flow model and it requires the steady-state assumption on chloride mass deposition only (and not on water fluxes or boundary conditions). The solutions and results are demonstrated on chloride profile data from west central New Mexico.
Date: December 1, 1996
Creator: Ginn, T.R. & Murphy, E.M.
Partner: UNT Libraries Government Documents Department

Global 3-d modeling of atmospheric ozone in the free troposphere and the stratosphere with emphasis on midlatitude regions. Final report, July 1, 1994--June 30, 1997

Description: The objective of this research is to use global chemical-transport models to study the chemical and dynamical processes that affect midlatitude stratospheric ozone and to quantify the budget of tropospheric ozone. Four models will be improved and used: (1) a new version of the two-dimensional chemical-radiative-dynamical model with microphysical process of sulfate aerosols and polar stratospheric clouds (PSCs), and heterogeneous conversions on the surfaces of sulfate aerosols and PSCs; (2) the stratospheric version of three-dimensional off-line chemical-transport model (STARS) with a relatively high horizontal resolution (2.8 degree in latitudes) with a microphysical formation of PSCs; (3) the tropospheric version of three-dimensional off-line chemical-transport model (MOZART) with details in the surface emissions and hydrocarbon reactions to estimate the tropospheric ozone budget and perturbations; (4) the intermediate model of the global and annual evolution of species (IMAGES) with a detailed chemical reactions but relatively lower resolutions. Model results will be compared with available data.
Date: December 1, 1997
Creator: Brasseur, G.; Erickson, D.; Tie, X. & Walter, S.
Partner: UNT Libraries Government Documents Department

GIS for Nevada railroads: 1993 report

Description: This is an interim report on a task within a large, ongoing study by the University of Nevada, Reno to examine the safety of Nevada railroads. The overall goal, of which this year`s research is a middle stage, is to develop models based on the use of geographic information systems (GIS). These models are to enable the selection of the best and safest railway routes for the transport of high-level nuclear waste across Nevada to the proposed repository at Yucca Mountain. Last year`s research concluded that the databases are adequate and that GIS are feasible and desirable for displaying the multi-layered data required to reach decisions about safety. It developed several database layers. This report deals with work during 1993 on the use of geographic information systems (GIS) for rail-route selection. The goal was to identify and assemble many of the databases necessary for the models. In particular, the research aimed to identify (a) any problems with developing database layers; and (b) the level of effort required. This year`s effort developed database layers for two Nevada counties: Clark and Lincoln. The layers dealt with: topographic information, geologic information, and land ownership. These are among the most important database layers. The database layers were successfully created. No significant problems arose in developing them. The level of effort did not exceed the expected level. The most effective approach is by means of digital, shaded relief maps. (Sample maps appear in plates.) Therefore, future database development will be straightforward. Research may proceed on the full development of shaded relief elevation maps for Elko, White Pine, Nye and Eureka counties and with actual modeling for the selection of a route or routes between the UP/SP line in northern Nevada and Yucca Mountain.
Date: December 1, 1993
Creator: Carr, J. R.
Partner: UNT Libraries Government Documents Department