Current repository design issues at Yucca Mountain, Nevada, U.S.A

Yucca Mountain, which is located approximately 175 km northwest of Las Vegas, Nevada, is the site that the US Department of Energy has selected to characterize in order to determine its suitability for disposing up to 70,000 tonnes of radioactive waste. This amount is comprised of approximately 63,000 tonnes of Spent Nuclear Fuel, and about 7,000 tonnes of High Level Waste. The Department of Energy is scheduled to begin taking possession of Spent Nuclear Fuel in 1998, but is not scheduled to actually dispose waste packages until the year 2010 if the site proves suitable for repository purposes. The project schedule is based upon a number of major milestones that are supported by High Level Findings of a scientific nature. These will collectively support the determination of Technical Site Suitability scheduled for 1998, an Environmental Impact Statement in 2000, and a License Application to construct in 2001. The overall project is comprised of two major phases: the Exploratory Studies Facility, and the potential repository. Both phases will make extensive use of mechanical excavation techniques in the development of main accesses, test alcoves, long term underground test rooms, and ultimately, emplacement drifts. Conceptual design will aid in formulating approaches to key issues of waste package configuration, thermal loading, material handling, retrieval and total site performance assessment