Development of the assessment tool for has migration scenario concerning sub-surface disposal

Sakatani, Keiichi; Nakamura, Yasuo; Tsuji, Tomoyuki ; Nakatani, Takayoshi 

The safety assessment for sub-surface disposal of radioactive wastes should ensure that calculated dose will be lower than the dose assigned to the scenario in question over the whole evaluation period of hundreds of thousands years. We have developed several assessment tools for the safe disposal of radioactive wastes on the GoldSim platform, and calculated doses since JFY 2008. These assessment tools have been improved reflecting the last view of assessment. In addition, we have developed an assessment tool for the gas migration scenario. This report describes concept of assessment model and structure of tool for the gas migration scenario.