Cask Mis-Loads Evaluation Techniques

Currently, there is over 74,000 metric tons of used nuclear fuel (UNF) in storage in the U.S. This corresponds to more than 260,000 UNF assemblies out of which approximately 91,000 are stored in over 2,200 dry storage systems, while the rest are stored in UNF pools at the reactor sites. The UNF increases by 2,000-2,300 metric tons per year. In 2012, the U.S. Department of Energy (DOE) established the Nuclear Fuels Storage and Transportation (NFST) project to develop and begin implementation of a management plan. The main objectives of NFST are to (1) implement interim storage, (2) improve integration of storage into an overall waste management system, and (3) prepare for large-scale transportation of UNF and high-level waste. There are currently two tentative plans to build consolidated interim storage facilities. It is expected that the number of UNF transportation events will drastically increase in the near future. As such, it is essential to monitor the condition and stability of the transport cask internals to maintain sub-criticality of the fissile materials in the fuel during normal conditions of transport (NCT) and hypothetical accident conditions (HAC), particularly after long-term storage in dry casks or UNF pools for several decades.