THE YUCCA MOUNTAIN PROJECT REPOSITORY SEALING PROGRAM*

Year
1989
Author(s)
Joseph A. Fernandez - Sandia National Laboratories
Thomas E. Hinkebein - Sandia National Laboratories
Abstract
Yucca Mountain is being characterized to determine its suitability for a high-level nuclear waste repository. The repository would be located in the unsaturated zone in fractured, welded tuff. Sealing of the repository is one element of the Yucca Mountain Project. This paper presents a description of the current sealing design options, design requirements, and the design constraints. Design options for the shafts include anchor-tobedrock seals, shaft fill, and settlement plugs; in the underground facility, they include drift seals, drainage channels, sumps, and bulkheads. Design requirements are those quantitative requirements imposed on the sealing design options to achieve a desired level of performance. For example, a design requirement could be a restriction on the hydraulic conductivity required for a design option. Constraints are restrictions placed on the repository design by the sealing design. An example of a constraint could be establishing the drainage pattern to direct flow from emplacement drifts to nonemplacement drifts. As (1) additional hydrogeologic data are obtained through site characterization, (2) approaches to allocating performance to various subsystems within the Yucca Mountain Project ,are refined, and (3) the exploratory shafts and the associated testing results are developed, the design requirements and constraints may be modified and used in developing the License Application Design.