Study of Subsurface Disposal Concepts for Uranium Waste

Yamamoto, Masayuki*; Ishibashi, Makoto*

Uranium waste has features that the main nuclide is long-lived uranium and it is not almost necessary to consider radiation influence from waste package. Although the many studies for subsurface disposal concept of uranium waste have been done, the wastes features were not carefully considered in the former studies. The following reasonable disposal concepts have been designed considering the features in this study. (1) Concrete vault disposal concept in rock cavern (2) Monolithic disposal concept in rock cavern (3) Trench disposal concept in rock cavern / The safety of the disposal concepts during operation and after control phase has been investigated in this study. As the result, it has been shown that the exposure dose of workers due to waste package is not high. And it has been shown that the exposure dose of the public does not change so much, even if the engineered barrier has been reduced. Besides some issues regarding regulation, operation and monitoring have been picked up.