Integration of Postclosure Safety Analysis with Repository Design for the Yucca Mountain Repository through the Selection of Design Control Parameters

Abstract

The Yucca Mountain repository will use both natural and engineered barriers that work both individually and collectively to limit the movement of water and the potential release and movement of radionuclides to the accessible environment. Engineered structures, systems, and components are designed to function with features of the natural environment in order to meet the postclosure performance objectives established by the Nuclear Regulatory Commission. The features of the natural environment are expected to respond to the presence of the repository through geomechanical, hydrogeologic, and geochemical changes. In order to ensure that conformity between the design basis of the repository and the analyzed postclosure safety basis is maintained, specific features, both engineered and natural, have been identified as requiring design control during repository construction and operations. These features are referred to as postclosure design controls and are intended to maintain the integration of the repository design with the postclosure performance assessment through continued design evolution and changes in scientific understanding.