HIGH-LEVEL WASTE REPOSITORY PERFORMANCE ASSESSMENT

The U.S. Department of Energy (the Department) has been charged by law with the responsibility to site, design, construct, operate, and permanently close a mined geologic disposal system (repository) for the permanent isolation of high-level radioactive waste and spent nuclear fuel. The Department is to prepare a License Application to the U.S. Nuclear Regulatory Commission (the Commission). The Commission will license the repository if the License Application provides sufficient evidence for the Commission to be able to find that the repository will meet regulatory requirements with reasonable assurance. Performance assessments are those calculations that demonstrate compliance with regulatory performance objectives. This paper gives an overview of the types of activities that are included in the Department's performance assessment program and the regulatory requirements being addressed. Preliminary sample calculations are given for the four major regulatory performance objectives, and sensitivities and uncertainties are discussed.