Uncertainty analysis of multiple canister repository model by earth simulator

Uncertainty analysis for repository performance has been made by using the VR code, which incorporates effects of canister multiplicity in the repository. In the previous study with the VR code, it was found that the effects of neighboring canisters on the release of radionuclides from the canister of interest are significant. In the previous study, however, the number of connected canisters was determined arbitrarily. In this study, the Np-237 release rate to the far-filed has been obtained by using the probability distribution functions for the number of canisters connected by fracture clusters in the two-dimension repository model obtained in the companion paper. The uncertainty has been quantitatively evaluated based on uncertainties associated with the input parameters such as buffer sorption coefficient, the solubility and the number of connected canisters. The VR code has been transplanted to Earth Simulator for large scale calculation. It has been shown that the uncertainty with the number of connected canisters significantly affects the uncertainty of the Np-237 release rate. (author)