Safety Evaluation of Shipping Cask for Loading 4 PWR Spent Fuel

The B type package development program was being carried out to transport spent fuel from temporary at-reactor(AR) storage pools short of enough storage capacities to other AR storage pools with available spaces or to away-from-reactor(AFR) interim storage facility to be built in the future . In order to transport spent fuel assemblies, a shipping cask is inevitable. Spent fuel to be shipped in casks is dangerous due to high radioactivity and decay heat. All kinds of casks should be evaluated to determine their thermal responses, rad- iation and radioactve materials release, and criticality. The cask must meet the regulatory standards stipulated in domestic atomic energy law and IAEA Safety Series No. 6. The standards require that the cask prevent the loss or dispersion of radioactive material, retain shielding efficiency, assure nuclear criticality safety, and be adequate to heat dissipation under normal conditions of transporta- tion and under hypothetical accident conditions.