Result of material accountancy and control and an evaluation for MUF at the Tokai Reprocessing Plant

The Tokai Reprocessing Plant commenced its first hot test campaign in September 1977, followed by seven successive campaigns up to December 1980. It acquired a licence from the Japanese government as a reprocessing plant at the end of December 1980 and began fully fledged operation in early 1981. Two further campaigns were carried out by the end of 1981. During these ten campaigns about 120 tonnes of spent fuel had been treated and about 690 kg of plutonium had been recovered. The paper describes the results of material accounting performed in these campaigns and of the investigation of plutonium MUF, especially in the C-1 and C-2 campaigns, since a relatively large amount of spent fuel was treated in them. In accountancy at a KMP between the process MBA (JR2A) and the storage MBA (JR3A) small quantities of bias always had existed. The result of an investigation using available past data shows two facts which seem to have contributed to the MUF in the JR2A. The MUF of the whole plant in each campaign is smaller than the MUFs occurring in each MBA and the cumulative amount of MUF is very small, indicating excellent material accountancy in the plant. (author)