Quantification of uncertain outcomes from site characterization: Insights from the ESF-AS

As part of the Exploratory Studies Facility Alternatives Study (ESF-AS) the uncertain outcomes from site characterization were quantified using a probabilistic tree known as ''Nature's Tree.'' Nature's Tree distinguished the true characteristics of the Yucca Mountain site from the perceived characteristics deduced from testing. Bayesian probabilistic calculations converted probabilities in Nature's Tree to the probabilistic estimates required for the comparative analysis of Exploratory Studies Facility-repository options. Experts on characterization testing explicitly addressed several site characterization issues that are considered implicitly in many site characterization programs