The mission of the Engineering Research, Development, and Technology Program at Lawrence Livermore National Laboratory (LLNL) is to develop the knowledge base, process technologies, specialized equipment, tools and facilities to support current and future LLNL programs. Engineering's efforts are guided by a strategy that results in dual benefit: first, in support of Department of Energy missions, such as national security through nuclear deterrence; and second, in enhancing the collaboration with US industry and universities in pursuit of the most cost-effective engineering solutions to LLNL programs. To accomplish this mission, the Engineering Research, Development, and Technology Program has two important goals: (1) identify key technologies relevant to LLNL programs where they can establish unique competencies, and (2) conduct high-quality research and development to enhance their capabilities and establish themselves as the world leaders in these technologies. To focus engineering's efforts, technology thrust areas are identified and technical leaders are selected for each area. The thrust areas are comprised of integrated engineering activities, staffed by personnel from the nine electronics and mechanical engineering divisions, and from other LLNL organizations. This annual report, organized by thrust area, describes Engineering's activities for fiscal year 1997. The report provides timely summaries of objectives, methods, and …

The legacy of nearly five of rapid industrialization throughout the Southwest includes sites where volatile contaminants have been accidentally or intentionally released at or immediately below the surface. Understanding the mechanism and rate of volatile transport trough the vadose zone is important to assessing the potential impact on groundwater resources. This is particularly significant in and environments where the inseminated (vadose) zone above the water table may be more than 300 m thick. While numerical models have been developed to predict the movement of volatiles trough the unsaturated zone, there are only limited opportunities to verify predictions against field data. Field measurements of vadose zone transport are important in terms of constraining model parameters and can be applied to a variety of contaminant issues. This includes the ability to monitor and detect deep underground explosions in violation of nuclear test ban treaties. We have investigated the movement of vadose zone gases in a deep alluvial basin at the Nevada Test Site. The opportunity to study the migration of soil gases in this setting is unique due to the access afforded by the Joint Test Organization`s U-la tunnel complex, mined at a depth of approximately 300 m below ground surface in …