The Use of Formal and Informal Expert Judgments When Interpreting Data for Performance Assessments

Abstract

ABSTRACTThis paper discusses the general process by which data and information are compiled and used for defining modeling parameters. These modeling parameters are input for the mathematical models that are used in performance assessments of the Waste Isolation Pilot Plant (WIPP), near Carlsbad, NM, which is designed to safely manage, store, and dispose of transuranic radioactive wastes. The physical and temporal scales, and the difficulty of obtaining measurements in geologic media make interpretation of measured data, including the difference between laboratory experiment scale and repository scale, important tasks. In most instances, standard scientific practices can ensure consistency of data use. To illustrate this point, an example is provided of the interpretation of field measurements of intrinsic permeability for use in computational models using the bootstrap technique. In some cases, sufficient information can never be collected, interpretation of the information is controversial, or information from diverse disciplines must be used. A procedure that formalizes the standard scientific practices under these conditions has been developed. An example is provided of how this procedure has been applied in eliciting expert judgments on markers to deter inadvertant human intrusion into the WIPP.