An assessment of spent nuclear fuel storage demands under uncertainty

This paper attempts to draw quantitative prospects of spent nuclear fuel (SNF) management in Japan, with emphasis on uncertainty of storage needs for SNF up to the year 2050. In a medium term up to the years 2020–2030, the storage need for SNF can be projected with relatively high accuracy as it steadily increases up to the level of 5000 tonnes of uranium (tU), which requires timely deployment of storage facilities accordingly. In a longer term up to 2050, a number of aspects may give influences on the SNF management strategy, which are analyzed in different sets of scenario assumptions. The results of quantitative simulation runs showed that the storage need for SNF will increase up to the level of 10,000 tonnes of heavy metals (tHM) in the Base Case, while it would further grow to 20,000–25,000 tHM in the Risk Management Cases. Careful attentions should be given to the point that not just quantity but characteristics of SNF to be stored will differ significantly among the simulation cases, such as from lower to higher burnup, uranium and MOX (mixed oxide) fuels. The results imply Japan's SNF management may require elaborate strategies, which consists of effective and timely measures into the future.