Publications

The PCP, Inc. Large Reaction Volume ion Mobility Spectrometer (LRVIMS) was characterized and evaluated for use as a contraband explosives vapor detector in personnel and package portal screening applications. The limit-of-detection was found to be a constant {approximately}0.3 PPT experimentally and in calibrations using a Thermedics RDX generator. The minimum LOD in terms of RDX vapor molecular flow rate was {approximately}1.8 {times} 10{sup 9} molecules/sec at 16.6 L/min airflow through the 100 cm{sup 2} square tube area of this ion mobility spectrometer. Samples of 0.5 gm of TNT in plastic bags in the center of the personnel screening portal were easily detected. Bomb quantity (8 oz) samples of TNT and Comp B (40% TNT, 60% RDX) were also detectable in the personnel portal configuration. No detections of RDX were possible in any position of either C-4 or Comp B or of PETN in Detasheet or Det Cord. Operation in the presence of observed background interferants, operation at very low airflow rates, and proposed operation in conjunction with preconcentrators, also are described. 14 figs.

This status report presents preliminary analyses of flow through the rooms, drifts, seals, and shafts of the Waste Isolation Pilot Plant (WIPP). The purpose of these analyses is to evaluate the importance of various components and parameters of the transuranic waste repository. These analyses are presented to show the current status of repository/shaft system modeling, and to provide input for evaluating proposed engineered modifications to the waste and rooms to ensure compliance with the Environmental Protection Agency's Environmental Standards for the Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Waste. Detailed descriptions are given for nine computational models of the WIPP repository for either undisturbed or human intrusion conditions. Some models are refined versions of earlier models; others include rudimentary studies of an additional phenomenon, flow of generated gas. The models of an undisturbed repository substantiated the results of earlier models by showing that no waste leaves the vicinity of the disposal area in 10,000 yr. The models that studies gas flow agreed with this position; however, the models are too rudimentary to permit conclusive statements. The five models of the human intrusion event explored the importance of parameters that influence the flow of brine through the waste, establishing a base for understanding the behavior of the waste disposal rooms, drifts,and interbeds in the host rock. 63 refs., 92 figs., 29 tabs.

In 1981 the Waste Isolation Pilot Plant (WIPP) Project, under the direction of the US Department of Energy (DOE), began construction of a facility in southeastern New Mexico to develop the technology for disposing of radioactive waste from the defense programs. This facility may eventually become a repository for defense Transuranic (TRU) wastes, provided that the facility is demonstrated to be acceptable. Although the complete facility includes both surface and underground construction, the Repository Isolation Systems Division of the Nuclear Waste Technology Department at Sandia National Laboratories (SNL) is primarily concerned with development of the underground portion of the facility; we focus on that portion of the facility in this report. This report is specific to the Thermal Structural Interactions (TSI) in situ tests of the Experimental Area and is one of a series intended to document the data obtained from the TSI in situ tests and to make these data available to potential users. 32 refs., 60 figs., 29 tabs.

This report documents the software developed to characterize tuning fork resonators used in the Quartz Digital Accelerometer. The results, after characterizing numerous resonators, indicate a resonant frequency sensitivity to input drive level. Also, the resonant frequency increased for some of the tuning fork resonators but decreased for others. The characterization process used to obtain these results is summarized. 4 refs., 14 figs.

The equilibrium swelling of silicones, fluorosilicones, VITON and ethylene-propylene-diene (EPDM) elastomers in an environment of the jet fuel JP4 was investigated. The volume of silicone and DPDM elastomers increased by approximately 100% when they were placed in a saturated environment of JP4. Conversely, the volume of the fluorosilicone elastomer increased by approximately 15% and that of VITON less than 1%. In acetone, a commonly used solvent, the equilibrium swelling of VITON and the fluorosilicone elastomer was excessive, on the order of 100%, wheras the silicone and EPDM elastomers exhibited small changes in dimensions. Reasons for these observations are discussed in detail. We also present a simple scheme by which one may, qualitatively, determine the dimensional stability of these elastomers in different solvents if the cohesive energy density of the solvent, which is readily available in a number of handbooks, is known. We also evaluated the vulnerability of some commonly used engineering thermoplastics to JP4. The results are tabulated. 13 refs., 6 figs., 3 tab.

An understanding of dispersal of nuclear materials from an explosive event is needed to support design studies of weapon storage and transportation. Assessing the consequences and requirements for cleanup of a fire or nonnuclear detonation of a system containing nuclear material requires knowledge of the aerosol formation process. Information about the aerosol chemical composition, the physical size and shape of the particulates, as well as the efficiency of aerosol formation ate needed to conduct meaningful assessments. This report describes laboratory tests to study aerosol from materials of interest. An electromagnetic launcher is used to heat and propel molten metallic samples under energetic high-velocity conditions. We describe the apparatus and first results from tests using uranium-molybdenum alloy samples. Contained laboratory-scale measurements are described that determine aerosol morphology, chemical composition, and aerosol formation efficiency under high-velocity conditions. Data from the launcher tests describe (1) the aerodynamic breakup process of high-velocity molten liquid into droplets, and (2) the formation of still finer aerosols by combustion of these droplets at high velocity. The measurements show efficient aerosol production in air that is dominated by the formation of fine chain-agglomerate combustion aerosol. Particle morphology information for both the chain agglomerate and the less common liquid breakup products is described. The aerodynamic breakup of the liquid sample material is described. Lognormal distributions are shown to accurately represent the data. The geometric mean diameter is related to the mass mean diameter and maximum stable droplet diameter for the distributions. 28 refs., 27 figs., 3 tabs.

Several potential incident scenarios involving the accidental release of radioactive material at five reference, nonreactor nuclear material licensees are analyzed in this report. The economic risk ($/licensee/yr) of decontamination is evaluated for each reference licensee. Although most releases and cleanup costs are minor, some less frequent incidents may result in very high cleanup costs that dominate the economic risk of decontamination of a particular licensee. The economic risk for the 5 plants ranged from a low of $14,000 per licensee per year to a high of $104,000 per licensee per year. This report is the second of two reports by Sandia National Laboratories on the economic risk of nonreactor nuclear material licensee operations. 40 refs., 21 figs., 31 tabs.

A two-part polyurethane foam supplied by Poly Plug, Inc., has been tested in the laboratory and in the field to assess its utility in controlling lost circulation encountered when drilling geothermal wells. A field in The Geysers was conducted, based on earlier laboratory work that showed the foam chemical formulation to be capable of expanding under elevated temperatures and pressures to form a rigid, impermeable polymer that should be effective in plugging fluid-loss zones. Although the downhole tool used to deploy the foam chemicals apparently functioned properly in the field test, the chemicals failed to expand significantly downhole, instead forming a dense polymer that may be ineffective in flowing into and sealing loss zones. Subsequent laboratory tests were conducted under simulated downhole conditions to determine the cause of the polymer's failure to sufficiently expand. The results indicate that the foam chemicals undergo vigorous mixing with water in the wellbore, which disturbs the kinetics of the chemical reaction more than was previously contemplated. The results indicate that without significant changes in the foam chemical formulation or delivery technique, the existing foam system will be ineffective in lost circulation control except under very favorable conditions. 6 refs., 46 figs., 7 tabs.

Both the US Environmental Protection Agency (EPA) and the US Nuclear Regulatory Commission (NRC) have promulgated regulations regarding the performance of geologic repositories for the disposal of high-level nuclear waste. One of the responsibilities of the US Department of Energy (DOE) is to demonstrate compliance with the appropriate regulations. The DOE will most likely use extensive numerical modeling to show compliance with the various quantitative requirements. These analyses will then be evaluated by the NRC. There are different levels of evaluation: peer review, conservative estimates,used of existing models/codes, and development of models/codes by the NRC. The intensity of the review will vary from analysis to analysis, depending on the importance of the analysis, the acceptability of the conceptual model behind the analysis and the solution technique used, and the potential for increasing confidence in the system description, should the NRC decide to develop its own models/codes. An appropriate level of review can be determined by applying these four criteria in a specific manner. 24 refs.

This report examines the computational implementation of a continuum model for jointed rock media. The jointed rock model uses strain partitioning between the elastic rock matrix and joint sets with nonlinear normal and shear responses. A specific model using a rational polynomial to describe normal joint response was first used as the basis for a computational implementation of a jointed rock model for two-dimensional problems. This particular implementation can be extended to three dimensions, but it would be a very expensive material model from a computational standpoint. The problem of trying to implement a joint model in three dimensions so that it would not be an extremely expensive computational tool has led to a study of various computational implementations of joint models for two-dimensional geometries. These studies have produced implementations of joint models that are very computationally efficient and that can handle joint models with normal joint behavior described by general relations. The implementations studied in this report make the use of jointed rock models in three dimensions much more feasible in terms of computational expense. 6 refs., 8 figs., 2 tabs.

This report describes research leading to the development of new catalytic materials based on hydrous metal oxide (HMO) ion exchangers. Present in this part, the second of two parts, are results of catalyst-related research and application of the materials to catalytic reactions for direct coal liquefaction processes. HMO materials are inorganic ion exchangers, derived from the alkoxides of Ti, Zr, Nb, or Ta, that exhibit a number of properties applicable to the preparation of catalysts. Research on the catalytic properties of HMO's has focused on the hydrous titanium oxide (HTO) system. However, exploratory coal liquefaction experiments with hydrous niobium oxides (HNO's) and hydrous zirconium oxides (HZO's) have demonstrated that these HMO's also exhibit potential as coal liquefaction catalysts. Studies performed during the course of this research include (1) preliminary coal liquefaction and hydrotreating tests, (2) tests of hydrogenation, hydrodesulfurization, hydrodeoxygenation and hydrodenitrogenation activity using model compounds, (3) development of catalyst pretreatment and activation procedures, (4) modification of HTO supports with silicon, (5) preparation and testing of thin film HTO catalysts, (6) synthesis, characterization and evaluation of base and noble metal catalyst deactivation tests, and (9) exploratory tests of applications other than direct liquefaction. The versatility of the HTO system for synthesis of catalysts allows great potential for further improvements in activity and selectivity as well as tailoring of catalysts for specific processes. Research is continuing in these areas. 54 refs., 63 figs., 25 tabs.

Drillholes H-14 and H-15 were drilled to investigate data gaps in the hydrologic hole distribution at the WIPP site. In addition to the information gained on the Culebra Dolomite Member, the holes yielded hydraulic and/or stratigraphic information on the Forty-niner, Magenta Dolomite, and Tamarisk Members of the Rustler Formation in an era where no such information was available. Hydraulic tests were also conducted on the lower part of the Dewey Lake Redbeds in H-14. A suite of geophysical logs was run on the drillholes and was used to identify different lithologies and aided in the interpretation of the hydraulic tests. 3 refs., 4 figs., 6 tabs.

This report describes the development of the following new catalytic materials based on hydrous metal oxide (HMO) ion exchange materials: Na-Ti, Nb, Zr, and mixtures of hydrated silica with hydrous Ti-oxide. HMO's provide a versatile system for the preparation of heterogeneous catalysts. The preparation chemistry allows synthesis of catalysts that can be tailored to particular processes with respect to both chemical and physical properties. Bulk catalysts with surface areas over 300 m{sup 2}/g and pore volumes up to 0.4 cc/g as well as thin films of the HMO materials can be prepared on supports having a wide range of catalytically important physical properties. This report, the first of two parts, presents research performed to date regarding the preparation chemistry, and physical and chemical properties of HMO materials which may be used to develop heterogeneous catalysts for direct coal liquefaction processes. During the course of this work, new ideas for research areas relative to direct coal liquefaction were briefly explored. Two of them that merit further work, catalyst-anchored hydrogen donors and alkoxide-derived crystalline titanate compounds, are briefly described. 25 refs., 34 figs., 8 tabs.

Drillholes H-17 and H-18 were drilled at the WIPP site to assess uncertainties in site hydrologic parameters and to serve as monitoring points for planned hydrologic tests. H-17 was drilled south of H-11 and east of P-17 to evaluate the existence of a high-permeability region in the Culebra Dolomite Member that had been indicated by groundwater-flow modeling and surface geophysical surveys. H-18 was drilled north of H-2 to help reduce the uncertainties of boundaries between high and low transmissivities and fluid density that had been identified by drilling and by modeling. 1 ref., 4 figs., 6 tabs.

An extensive literature review has been conducted as part of an effort to quantify the fidelity of Sandia's lightning burn-through simulation technique. The dominant parameters affecting damage have been identified and are discussed. Two alternative techniques for qualitatively improving the Sandia simulation have been identified, but quantification of the correlation of the results of each with those of natural lightning awaits completion of further experimental work. A systematic set of laboratory experiments is proposed to assess the sensitivity of each technique to key simulation parameters. An available calibration linkage to natural lightning is the reproduction of damage spots that were created by lightning on a set of copper disks mounted on TV towers, and an attempt to do this is included in the proposed experiments. In order to reduce the uncertainties of this approach, more lightning-spot data are required, along with records of the flash currents that produced them. It is recommended that such data be acquired in conjunction with the Rocket-Triggered Lightning Program being conducted each summer at the Kennedy Space Center. 25 refs., 5 figs., 1 tab.

The inverse triax diode is a high power, low impedance electron diode which offers significant advantages over conventional electron diodes on short-pulse (<30 ns FWHM) high power x-ray simulators. Parametric calculations show that the radiation efficiency of the inverse triax is competitive with standard diodes fro mean photon energies below about 120 keV, and sometimes up to 150 keV. Particle-in-cell code simulations show the impedance behavior and flow pattern in the inverse triax with and without the presence of an anode plasma. The simulation results are used to suggest design rules for inverse triax diodes. Experimental results show good agreement with calculations of the impedance behavior and electron beam dynamics. Using inverse triax diodes, we have produced peak doses of 1.4 {times} 10{sup 11} rad(TLD)/s over 840 cm{sup 2} with a mean photon energy of 120 keV on SPEED and 3.1 {times} 10{sup 11} rad(TLD)/s over 3700 cm{sup 2} with a mean photon energy of 140 keV on Saturn. 20 refs., 16 figs.

The BES Materials Science program at Sandia Albuquerque has the central theme of Scientifically Tailored Materials. The major objective of this program is to combine Sandia's expertise and capabilities in the areas of solid state sciences, advanced atomic-level diagnostics and materials-processing science to produce new classes of tailorable materials for the US energy industry, the electronics industry and for defense needs. Current research in this program includes the physics and chemistry of ceramics, the use of energetic particles for the synthesis and study of materials, high-temperature and organic superconductors, tailored surfaces for materials applications, chemical vapor deposition sciences, strained-layer semiconductors, advanced growth techniques for improved semiconductor structures and boron-rich very high temperature semiconductors. A new start just getting underway deals with the atomic level science of interfacial adhesion. Our interdisciplinary program utilizes a broad array of sophisticated, state-of-the-art experimental capabilities provided by other programs. The major capabilities include several molecular-beam epitaxy and chemical-vapor-deposition facilities, electron- and ion-beam accelerators, laser-based diagnostics, advanced surface spectroscopies, unique combined high-pressure/low-temperature/high-magnetic-field facilities, and the soon to be added scanning tunneling and atomic force microscopies.

Calorimetry was performed on Sandia National Laboratories' Test Bed Concentrator {number sign}1 (TBC-1) during late July and early August 1989. The purpose of the tests was to determine the total power available from the concentrator and the amount of the total power that can be focused through a 22-cm aperture plate located at the nominal focal point of the dish. The 22-cm aperture corresponds to the diameter of several reflux receivers that are currently under development, fabrication and testing at Sandia. The calorimeter test will allow the efficiency of the sodium reflux receivers to be calculated. The total power (normalized to 1000 W/m{sup 2}) available from TBC-1 is 66.4 kW into the 22-cm aperture plate. Within error limits, this power level is the same with or without the aperture plate. The power levels stated are for this time (July 1989) and will probably change as the mirrors further degrade. Since the last calorimetry tests were performed, the mirror facets have degraded significantly, and the results presented here support this effect. Finally, three of the 220 facets were missing. 3 refs., 5 figs., 2 tabs.

This report presents a method of running batch jobs from menu-driven interactive EQUEL programs. EQUEL is the embedded query language of INGRES, a popular database management system used widely at Sandia. The method is framed in the VAX/VMS operating system environment.

For more than 10 years, the US Department of Energy's Solar Thermal Program has pioneered the development of heliostats, mirrors that track the sun, for solar central-receiver power plants. The field of heliostats is the single most expensive part of such plants, so their cost must be as low as possible for the technology to be commercially successful. Recent efforts have focused on the development of heliostats that use stretched-membrane reflectors in place of the more familiar glass mirrors. In such heliostats, metal foils are stretched over both sides of a large-diameter metal ring. The reflective surface is a silvered-polymer film glued to the front membrane. A slight vacuum in the space between the two membranes is actively controlled to provide a concave, focused contour to the mirror, and in an emergency this space can be rapidly pressurized to defocus it. Because of their simplicity and lighter weight, stretched- membrane heliostats have the potential to cost significantly less than current glass-mirror designs. The first 50-m{sup 2} mirror modules, built under contract to Sandia in 1986, demonstrated that membrane heliostats could perform at least as well as heliostats using glass mirrors. Insights gained from Sandia's testing and evaluation of the first-generation units were incorporated into the designs of two improved 50-m{sup 2} mirror modules. The results of Sandia's evaluation show significant improvement in optical performance over the first-generation designs, especially in windy conditions. 22 refs., 29 figs.

This report describes the application of word processing, graphics and data base software to the task necessary for the exclusion of Building 823 from the secure technical area at Sandia National Laboratories. In particular, this report focuses on the development of the building floor plans layouts and the space/personnel data base which were used by management to plan and coordinate the project. Once the project is complete, these information systems will continue to be maintained by other personnel for administrative purposes. The software developed has potential applicability to other facilities where administrative monitoring or space assessment is required. 6 figs.

Personnel from Stockpile Evaluation Program Division I, 7261, have been testing Joint Test Assemblies (JTAs) at Meppen Range, Federal Republic of Germany (FRG) since 1984. JTA trajectories were obtained from cinetheodolite film. The MPS-36 radar at Meppen Range is required to track the aircraft before bomb release to verify the release parameters for range safety and for the bomb trajectory after release. This is a difficult task because of the low-level approach of the aircraft. Division 7261 personnel asked Tonopah Test Range Department 7170 to assist in solving radar tracking problems. We recommended a new closed-circuit television system with a zoom lens and a force-operated, two-axis joystick. This system provides the operator a means of overriding the automode of the radar and manually positioning the radar antenna in azimuth (AZ) and elevation (EL). The joystick operator keeps the target (aircraft or bomb) centered in the TV picture by applying the correct pressure to the joystick. At the same time, the radar console operator maintains automatic range tracking by assisting the range gate through ground clutter using the control level of the range gate, as a rate-aid control in automatic mode. During the period May 8-17, 1989, the visual tracking equipment was installed in the Meppen radar. On May 16, 1989 a bomb dummy unit, loft maneuver was tracked successfully. The video, with time of day, was recorded for posttest, quick-look data. In the ten years of planned testing, a twenty-fold cost savings would be achieved with incorporation of the visual tracking capability to the MPS-36 radar, rather than providing radar beacons on each JTA. 8 figs.

Sandia National Laboratories, as part of the Containment Integrity Programs under the sponsorship of the Nuclear Regulatory Commission (NRC), has developed analytical techniques for predicting the performance of light water reactor steel containment buildings subject to loads beyond the design basis. The analytical techniques are based on experience with large-scale steel containment model tests that provided important insights and experimental validation of the analytical methods. As a means of demonstrating these analytical techniques, the NRC asked Sandia to conduct a structural evaluation of an actual steel containment building. The objective of the analysis was to determine the actual pressure capacity and the mode, location, and size of failure, where a functional definition of failure is used. The purpose of this report is to document the calculations performed to determine the pressure limits for the shell- rupture mode of failure. General failure of the containment shell is predicted by application of a failure criterion to the results from finite element structural analyses. The failure criterion relates the calculated values of strain in the containment plates, due to internal-pressurization loading, to the ultimate strain limit of the steel. Included in the failure criterion are adjustments for factors inherent in finite element analysis, such as level of detail and element size of the finite element model and variations in material property data. Separate finite element models were used to evaluate the overall free-field behavior of the structure and the localized behavior at a specific penetration location. 18 refs., 68 figs., 10 tabs.

In an experiment conducted at Sandia National Laboratories, 1:6-scale model of a reinforced concrete light water reactor containment building was pressurized with nitrogen gas to more than three times its design pressure. The pressurization produced one large tear and several smaller tears in the steel liner plate that functioned as the primary pneumatic seal for the structure. The data collected from the overpressurization test have been used to evaluate and further refine methods of structural analysis that can be used to predict the performance of containment buildings under conditions produced by a severe accident. This report describes posttest finite element analyses of the 1:6-scale model tests and compares pretest predictions of the structural response to the experimental results. Strain and displacements calculated in axisymmetric finite element analyses of the 1:6-scale model are compared to strains and displacement measured in the experiment. Detailed analyses of the liner plate are also described in the report. The region of the liner surrounding the large tear was analyzed using two different two-dimensional finite elements model. The results from these analyzed indicate that the primary mechanisms that initiated the tear can be captured in a two- dimensional finite element model. Furthermore, the analyses show that studs used to anchor the liner to the concrete wall, played an important role in initiating the liner tear. Three-dimensional finite element analyses of liner plates loaded by studs are also presented. Results from the three-dimensional analyses are compared to results from two-dimensional analyses of the same problems. 12 refs., 56 figs., 1 tab.

The Yucca Mountain Project (YMP) is examining the feasibility of siting a repository for high-level nuclear waste at Yucca Mountain, on and adjacent to the Nevada Test Site (NTS). The proposed repository will be excavated in the Topopah Spring Member, which is a moderately fractured, unsaturated, welded tuff. Excavation stability will be required during construction, waste emplacement, retrieval (if required), and closure to ensure worker safety. The subsurface excavations will be subject to stress changes resulting from thermal expansion of the rock mass and seismic events associated with regional tectonic activity and underground nuclear explosions (UNEs). Analyses of drift stability are required to assess the acceptable waste emplacement density, to design the drift shapes and ground support systems, and to establish schedules and cost of construction. This paper outlines the proposed methodology to assess drift stability and then focuses on an example of its application to the YMP repository drifts based on preliminary site data. Because site characterization activities have not begun, the database currently lacks the extensive site-specific field and laboratory data needed to form conclusions as to the final ground support requirements. This drift design methodology will be applied and refined as more site-specific data are generated and as analytical techniques and methodologies are verified during the site characterization process.