Year
1989
Abstract
The material selection process that has been used to determine candidate seal materials for a possible high-level nuclear waste repository at Yucca Mountain is described here. This process includes the development of a logic for the initial selection and subsequent refinements in the selection of materials. Each refinement examines whether candidate seal materials possess several physical and chemical properties that are determined from seal design requirements. Each refinement provides a basis for materials performance, testing, and analysis. The first material evaluation identified broad materials groups (such as cementitious and earthen materials) and explained why other materials (such as ceramics and metals) are not being evaluated in current testing. The second material evaluation considered the hydraulic conductivity, strength, emplacement considerations, ground-water chemistry and emplacement environment of specific seal components. The result of the second material evaluation identified specific material types such as \"high-temperature concrete\" or \"lowpermeability crushed rock/clay\" for each of the seal components that may be included in the design.