Overview of scientific investigations at Yucca Mountain - the potential repository for high-level nuclear waste

The US Department of Energy (DOE) has been evaluating the unsaturated zone (UZ) at Yucca Mountain, Nevada, as a potential repository site for high lev el nuclear waste. A large number of boreholes have been drilled at the site , and an underground tunnel, the exploratory studies facility (ESF), has be en constructed. A variety of boreholes and underground tests have been cond ucted that have provided large amounts of data from the UZ. This paper summ arizes some of the current knowledge of geological and hydrological charact eristics of the site and provides the framework for a series of technical p apers that follow in this issue. A brief discussion is also given to the re pository safety strategy for Yucca Mountain and the UZ site-scale flow mode l. (C) 1999 Elsevier Science B.V. All rights reserved.