Risk methodology for geologic disposal of radioactive waste: interim report

The Fuel Cycle Risk Analysis Division of Sandia Laboratories is funded by the Nuclear Regulatory Commission (NRC) to develop a methodology for assessment of the long-term risks from radioactive waste disposal in deep, geologic media. The first phase of this work, which is documented in this report, involves the following: (1) development of analytical models to represent the processes by which radioactive waste might leave the waste repository, enter the surface environment and eventually reach humans and (2) definition of a hypothetical ''reference system'' to provide a realistic setting for exercise of the models in a risk or safety assessment. The second phase of this work, which will be documented in a later report, will involve use of the analytical models in a demonstration risk or safety assessment of the reference system. The analytical methods and data developed in this study are expected to form the basis for a portion of the NRC repository licensing methodology