U.S. NUCLEAR REGULATORY COMMISSION'S REGULATIONS FOR LONG-TERM SAFETY OF GEOLOGIC DISPOSAL OF HIGH-LEVEL RADIOACTIVE WASTE AT YUCCA MOUNTAIN, NEVADA
A comprehensive evaluation of performance requires identification of the features, events and processes (FEPs) that could affect repository performance; consideration of the uncertainty in parameters and models used to represent the FEPs; and evaluation of the complex interactions between the engineered barriers and the geology, hydrology and chemistry of the natural system. The understanding of repository performance, including consideration of uncertainties, must be supported by a wide variety of data and testing; such as information obtained from laboratory tests, field investigations, and natural analog studies. If NRC grants a license to DOE, the regulations require DOE to continue testing and evaluation of the adequacy of the assumptions, data, and analyses that permitted the construction of the repository and subsequent emplacement of waste. This required "performance confirmation" program would include in situ monitoring, and laboratory and field testing. Thus, NRC's licensing decision will be based on a comprehensive understanding of the overall behavior of the repository and its barriers that is supported by scientific information and data, and confirmed by an ongoing monitoring and evaluation process.