Exploratory Studies Facility alternatives study: Final report; Volume 2, A comparative evaluation of alternative exploratory studies facility options: Yucca Mountain Site Characterization Project

An Exploratory Studies Facility (ESF) is planned for use in the characterization of a potential site for a high-level nuclear waste repository at Yucca Mountain, NV. A comparative evaluation of ESF-repository design options was conducted for the Department of Energy`s Yucca Mountain Site Characterization Project Office. The purposes of the evaluation were to identify and rank order ESF-repository options and to improve understanding of the favorable or unfavorable features of an ESF design. The evaluation relied on techniques from decision analysis, including decision trees and multiattribute utility analysis (MUA). Decision trees provided a means for evaluating decisions under uncertainty. MUA provided a means for evaluating decisions with multiple, possibly competing objectives. Thirty-four ESF-repository options were evaluated and ranked based on inputs provided by 11 panels composed of technical specialists and one panel composed of senior managers. With guidance from decision analysts, the technical specialists developed the measures for quantifying performance; identified, developed, and analyzed scenarios for the development and operation of the ESF and the potential repository; and provided estimates of the probabilities of uncertainties and the performance of each option against various performance measures. With similar guidance, the senior managers specified the objectives and criteria for the evaluation, themore » value tradeoffs among objectives, and the attitude toward risk used in the analysis.« less