Sealing nuclear repositories

In developing a repository in a geologic host rock it is necessary to penetrate the host formation and overburden with exploratory boreholes, shafts, entry drifts, and waste chambers. Such penetrations might provide pathways for fluid flow and nuclide migration if they are not properly sealed. To facilitate sealing these penetrations, the office of Nuclear Waste Isolation has developed a repository sealing program. This paper discusses various aspects of the program, including sealing design goals, performance studies, design schedule, design development, and materials research