A PROBABILISTIC DERIVATION OF WASTE CONCENTRATION LIMITS FOR THE RADIOACTIVE WASTE MANAGEMENT SITES AT THE NEVADA TEST SITE

A probabilistic approach to performance assessment was used to derive waste concentration limits for the Area 5 and Area 3 Radioactive Waste Management Sites at the Nevada Test Site (NTS). Probabilistic techniques employed in the performance assessments include probabilistic treatment of parameter uncertainty, the occurrence of inadvertent human intrusion scenarios, and the longevity of institutional controls. Site-specific and probabilistic treatment of the intruder at NTS is appropriate given the location of the low-level waste disposal facilities in a remote desert environment. The probability of intrusion and the length of the institutional control period was estimated from the elicitation of a panel of subject matter experts (SMEs). The SMEs concluded that the probability of future inadvertent human intrusion and human settlement would be very low in the remote arid valleys of the NTS. Moreover, the SMEs believed that institutional controls were likely to be effective beyond 100 years at the NTS. The NTS SMEs estimated the probabilities of inadvertent human intrusion for a 10,000