Time is both the ally of high-level nuclear waste (HLNW) managers and the enemy. It is the ally because the radioactivity in elements and isotopes decreases with age, making the waste progressively less dangerous to human health and safety and the environment. This rate of radioactive decline varies, in some cases diminishing by half (the half life) in seconds, minutes, hours, days, weeks, months, or years. In other cases the decay process takes centuries or hundreds of thousands of years before the wastes are safe for human contact. The problem as now conceptualized for HLNW managers is simple to state if not easy to achieve. The HLNW needs to be secured in some fashion until it decays, by virtue of its physical nature, to safe levels. Another possible future solution, not currently available, might be to change the ~~ructure of HLNW through high-technology processing and thus decompose the waste into units with different and less lengthy radioactivity. Learning whether this processing is a future option will require patience and generous amounts of time for research.

During the next several years, decisions are expected to be made in several countries on the further development and implementation of the geological disposition option. The Board on Radioactive Waste Management (BRWM) of the U.S. National Academies believes that informed and reasoned discussion of relevant scientific, engineering and social issues can-and should-play a constructive role in the decision process by providing information to decision makers on relevant technical and policy issues. A BRWM-initiated project including a workshop at Irvine, California on November 4-5, 1999, and subsequent National Academies' report to be published in spring, 2000, are intended to provide such information to national policy makers both in the U.S. and abroad. To inform national policies, it is essential that experts from the physical, geological, and engineering sciences, and experts from the policy and social science communities work together. Some national programs have involved social science and policy experts from the beginning, while other programs have only recently recognized the importance of this collaboration. An important goal of the November workshop is to facilitate dialogue between these communities, as well as to encourage the sharing of experiences from many national programs. The workshop steering committee has prepared this discussion for participants at the workshop. It should elicit critical comments and help identify topics requiring in-depth discussion at the workshop. It is not intended as a statement of findings, conclusions, or recommendations. It is rather intended as a vehicle for stimulating dialogue among the workshop participants. Out of that dialogue will emerge the findings, conclusions, and recommendations of the National Academies' report.

This report looks at the Nuclear Waste Policy Act of 1982 (NWPA), Yucca Mountain, and the Obama Administration's de-funding of Yucca Mountain. Federal policy is based on the premise that nuclear waste can be disposed of safely, but proposed storage and disposal facilities have frequently been challenged on safety, health, and environmental grounds. Most of the current debate surrounding civilian radioactive waste focuses on highly radioactive spent fuel from nuclear power plants.