Publications Details
Investigation of cask contamination weeping: A progress report
Spent fuel transportation casks have arrived at final destinations with removable surface contamination levels in excess of regulatory limits, although pre-transport surveys indicated removable contamination levels were well below these limits. The control of this in-transit ''weeping'' of surface contamination on pool-loaded spent fuel transport casks is of particular concern to both the US Department of Energy (DOE) and the US Nuclear Regulatory Commission (NRC). Weeping, also known as sweating, is the transformation of fixed radioactive particulates on an exterior surface of transport cask to a removable state. Weeping has been observed sometime after a cask is removed from a fuel pool and decontaminated. The weeping phenomenon is countered by time-consuming operational constraints and procedures which have a significant impact on cask turnaround times and occupational exposures at transport facilities. Further, the arrival of a contaminated cask results in negative public perceptions that are inconsistent with DOE and NRC goals. The objectives in resolving the technical issue of weeping are to identify specific causes of the weeping phenomenon, then to implement new cask design requirements and supporting operational procedures which will limit or inhibit the accumulation, retention, and in-transit conversion of fixed surface contamination. 6 figs., 1 tab.