RAdio-nuclides Migration DAtasets (RAMDA) on Cement, Bentonite and Rock for TRU Waste Repository in Japan

TRU廃棄物処分の性能評価におけるセメント系材料,ベントナイト及び岩石に対する核種移行データセット(RAMDA)の整備

三原 守弘  ; 佐々木 良一

Mihara, Morihiro; Sasaki, Ryoichi

処分施設の性能評価に必要となるセメント系材料,ベントナイト及び岩石に対する核種移行データセット(RAMDA)について記述した。以下に示すデータセットについて示している。•放射性元素の溶解度,•放射性元素の実効拡散係数,•放射性元素の収着分配係数,RAMDAの整備にあたっては,セメント系材料及びベントナイトなどの処分施設材料の長期的な変遷を考慮した。

In Japan, some of low-level radioactive wastes (LLW) containing nuclides with long half-lives, such as transuranium (TRU) nuclides, fission products (e.g. iodine- 129) and activation products (e.g. carbon-14), will be generated by the operation and decommissioning of domestic and overseas reprocessing plants for spent nuclear fuel and a domestic MOX fuel fabrication plant. Such wastes are termed "TRU waste". The high activity wastes of them are panned to dispose under deep under-ground in future. The Federation of Electric Power Companies(FEPC) and the Japan Nuclear Cycle Development Institute (JNC) have been caring out the performance assessment (PA) for TRU waste disposal system. In this report, radio-nuclides migration datasets (RAMDA) of cement, bentonite and rocks for the PA are described. RAMDA contains the following dataset: (1)Radio-nuclides solubility (2)Effective diffusion coefficient of radio-nuclide (3)Sorption of radio-nuclide. For the establishment of RAMDA, the long-term evolution of the engineered barriers, such as cement mortar and compacted bentonite, was considered.