Estimation of radioactivity concentration limit for concrete vault disposal of transuranium and uranium wastes (Contract research)

Sawaguchi, Takuma ; Takeda, Seiji ; Sasaki, Toshihisa; Ochiai, Toru; Watanabe, Masatoshi; Kimura, Hideo

The Atomic Energy Commission of Japan states that the transuranium waste and uranium waste are to be disposed of by either near surface disposal without artificial barrier (trench disposal), near surface disposal with artificial barrier (concrete vault disposal), or intermediate depth disposal, depending on the radionuclides and their radioactivity concentration in the wastes. The ranges of radioactivity concentration for these different disposal concepts are, therefore, required to be determined for the regulation. The radioactivity concentration limits define the upper bound of radioactivity concentrations for licensing application of the disposal of radioactive waste. This document summaries the concept and method for estimation of the radioactivity concentration limits for concrete vault disposal of transuranium and uranium wastes, and provides the derived values of the radioactivity concentration limits for each radionuclide in the wastes.