[1N04-06] Uncertainty Evaluation

[1N05] Evaluation of Uncertainty of Radioactivity for Decommissioning

*Tatsuki Amitani¹, Tsunenori Inakura¹, Naoki Yamano¹, Ken-ichi Tanaka², Chikako Ishizuka¹, Ryoji Mizuno³, Masato Watanabe⁴, Satoshi Chiba¹ (1. Tokyo Tech, 2. IAE, 3. Chuden CTI, 4. Chubu Electric Power)

Keywords:Decommissioning, Clearance, Neutron cross section, Covariance, Uncertainty, Total Monte Carlo

To optimize disposal of low-level radioactive waste generated from decommissioning of nuclear facilities, required are 1) reliable assessment of radioactive level by calculation and measurement and 2) a good estimate of the uncertainty of those result for the classification of radioactive waste. In order to improve the reliability of the calculations, we evaluated the covariance of the neutron cross sections of ⁵⁹Co and ¹⁵¹Eu, which produce important nuclides, ⁶⁰Co and ¹⁵²Eu, for clearance level verification. In this study, we calculated effect of uncertainty in nuclear data on the radioactivity based on Total Monte Carlo method using ORLIBJ40.