Preliminary performance assessment of the Greater Confinement Disposal facility at the Nevada Test Site. Volume 3: Supporting details

The Department of Energy`s Nevada Operations Office (DOE/NV) has disposed of a small quantity of transuranic waste at the Greater Confinement Disposal facility in Area 5 of the Nevada Test Site. In 1989, DOE/NV contracted with Sandia National Laboratories to perform a preliminary performance assessment of this disposal facility. This preliminary performance assessment consisted of analyses designed to assess the likelihood of complying with Environmental Protection Agency standards for the disposal of transuranic waste, high level waste, and spent fuel. The preliminary nature of this study meant that no other regulatory standards were considered and the analyses were conducted with specific limitations. The procedure for the preliminary performance assessment consisted of (1) collecting information about the site, (2) developing models based on this information, (3) implementing these models in computer codes, (4) performing the analyses using the computer codes, and (5) performing sensitivity analyses to determine the more important variables. Based on the results of the analyses, it appears that the Greater Confinement Disposal facility will most likely comply with the Environmental Protection Agency`s standards for the disposal of transuranic waste. The results of the sensitivity analyses are being used to guide site characterization activities related to the next iterationmore » of performance assessment analyses for the Greater Confinement Disposal facility.« less