This report is an initial effort to identify and evaluate safety issues associated with the use of Flibe (LiF-BeF{sub 2}) as a molten salt coolant for nuclear fusion power plant applications. Flibe experience in the Molten Salt Reactor Experiment is briefly reviewed. Safety issues identified include chemical toxicity, radiological issues resulting from neutron activation, and the operational concerns of handling a high temperature coolant. Beryllium compounds and fluorine pose be toxicological concerns. Some controls to protect workers are discussed. Since Flibe has been handled safely in other applications, its hazards appear to be manageable. Some safety issues that require further study are pointed out. Flibe salt interaction with strong magnetic fields should be investigated. Evolution of Flibe constituents and activation products at high temperature (i.e., will Fluorine release as a gas or remain in the molten salt) is an issue. Aerosol and tritium release from a Flibe spill requires study, as does neutronics analysis to characterize radiological doses. Tritium migration from Flibe into the cooling system is also a safety concern. Investigation of these issues will help determine the extent to which Flibe shows promise as a fusion power plant coolant or plasma-facing material.

The US Department of Energy (DOE), through its CHAMMP initiative, hopes to develop the capability to make meaningful regional climate forecasts on time scales exceeding a decade, such capability to be based on numerical prediction type models. We propose research to contribute to each of the specific items enumerated in the CHAMMP announcement (Notice 91-3); i.e., to consider theoretical limits to prediction of climate and climate change on appropriate time scales, to develop new mathematical techniques to utilize massively parallel processors (MPP), to actually utilize MPPs as a research tool, and to develop improved representations of some processes essential to climate prediction. In particular, our goals are to: (1) Reconfigure the prediction equations such that the time iteration process can be compressed by use of MMP architecture, and to develop appropriate algorithms. (2) Develop local subgrid scale models which can provide time and space dependent parameterization for a state- of-the-art climate model to minimize the scale resolution necessary for a climate model, and to utilize MPP capability to simultaneously integrate those subgrid models and their statistics. (3) Capitalize on the MPP architecture to study the inherent ensemble nature of the climate problem. By careful choice of initial states, many realizations …

The Corrective Action Investigation Plan for Corrective Action Unit 263, the Area 25 Building 4839 Leachfield, has been developed in accordance with the Federal Facility Agreement and Consent Order that was agreed to by the US Department of Energy, Nevada Operations Office; the Nevada Division of Environmental Protection; and the US Department of Defense. Corrective Action Unit 263 is comprised of the Corrective Action Site 25-05-04 sanitary leachfield and associated collection system. This Corrective Action Investigation Plan is used in combination with the Work Plan for Leachfield Corrective Action Units: Nevada Test Site and Tonopah Test Range, Nevada (DOE/NV, 1998d). The Leachfield Work Plan was developed to streamline investigations at Leachfield Corrective Action Units by incorporating management, technical, quality assurance, health and safety, public involvement, field sampling, and waste management information common to a set of Corrective Action Units with similar site histories and characteristics into a single document that can be referenced. This Corrective Action Investigation Plan provides investigative details specific to Corrective Action Unit 263. Corrective Action Unit 263 is located southwest of Building 4839, in the Central Propellant Storage Area. Operations in Building 4839 from 1968 to 1996 resulted in effluent releases to the leachfield and associated …

The results of Sandia National Laboratories' participation in the NASA Planetary Definition and Design Program are summarized. Areas reported include the characterization of large area cadmium zinc telluride spectrometers and the application of simulation techniques to the prediction of device performance. Also investigated was the response of mercuric iodide devices in the region from 1 to 100 KeV. A literature study to determine the status or radiation damage measurements in room temperature semiconductor devices is also reported.

This report outlines the application of finite element methodology to large deformation solid mechanics problems, detailing also some of the key technological issues that effective finite element formulations must address. The presentation is organized into three major portions: first, a discussion of finite element discretization from the global point of view, emphasizing the relationship between a virtual work principle and the associated fully discrete system, second, a discussion of finite element technology, emphasizing the important theoretical and practical features associated with an individual finite element; and third, detailed description of specific elements that enjoy widespread use, providing some examples of the theoretical ideas already described. Descriptions of problem formulation in nonlinear solid mechanics, nonlinear continuum mechanics, and constitutive modeling are given in three companion reports.

Biomedical Engineering is the application of principles of physics, chemistry, nd engineering to problems of human health. The National Laboratories of the U.S. Department of Energy have been leaders in this scientific field since 1947. This inventory of their biomedical engineering projects was compiled in January 1999.

The Artificial Intelligence field of Integrating Multiple Learned Models (IMLM) explores ways to combine results from sets of trained programs. Aroclor Interpretation is an ill-conditioned problem in which trained programs must operate in scenarios outside their training ranges because it is intractable to train them completely. Consequently, they fail in ways related to the scenarios. We developed a general-purpose IMLM solution, the Combiner, and applied it to Aroclor Interpretation. The Combiner's first step, Scenario Identification (M), learns rules from very sparse, synthetic training data consisting of results from a suite of trained programs called Methods. S1 produces fuzzy belief weights for each scenario by approximately matching the rules. The Combiner's second step, Aroclor Presence Detection (AP), classifies each of three Aroclors as present or absent in a sample. The third step, Aroclor Quantification (AQ), produces quantitative values for the concentration of each Aroclor in a sample. AP and AQ use automatically learned empirical biases for each of the Methods in each scenario. Through fuzzy logic, AP and AQ combine scenario weights, automatically learned biases for each of the Methods in each scenario, and Methods' results to determine results for a sample.

Measurements of the fugacity of carbon dioxide (fCO2) in surface seawater are an important part of studies of the global carbon cycle and its anthropogenic perturbation. An important step toward the thorough interpretation of the vast amount of available fCO2 data is the establishment of a database system that would make sure measurements more widely available for use in understanding the basin- and global-scale distribution of fCO2 and its influence on the oceanic uptake of anthropogenic CO2. Such an effort, however, is based on knowledge of data sets from different laboratories. Currently, however, there is not much known about this subject.

This issue of the Natural Gas Monthly contains estimates for March 1999 for many natural gas data series at the national level. Estimates of national natural gas prices are available through December 1998 for most series. Highlights of the data contained in this issue are listed below. Preliminary data indicate that the national average wellhead price for 1998 declined to 16% from the previous year ($1.96 compared to $2.32 per thousand cubic feet). At the end of March, the end of the 1998--1999 heating season, the level of working gas in underground natural gas storage facilities is estimated to be 1,354 billion cubic feet, 169 billion cubic feet higher than at the end of March 1998. Gas consumption during the first 3 months of 1999 is estimated to have been 179 billion cubic feet higher than in the same period in 1998. Most of this increase (133 billion cubic feet) occurred in the residential sector due to the cooler temperatures in January and February compared to the same months last year. According to the National Weather Service, heating degree days in January 1999 were 15% greater than the previous year while February recorded a 5% increase.