Influence evaluation of spent bed material in the conversion facilities. Evaluation of the external exposure caused by removing the spent bed material in the conversion facilities

At the conversion facility, dismantlement and removal of the equipment are executed according to the decommissioning plan. The radioactivity of the spent bed material discharged along with the reprocessed uranium conversion is high. So, there is concern that the external exposure caused by the dismantlement of the spent bed material storage is high. Therefore, the uranium isotopic analysis using the gamma-ray measurement intended for the spent bed material was done, and the external exposure at site boundary was evaluated. As a result, the external exposure at site boundary is low. The external exposure caused by dismantlement work was evaluated, and the points to remember for dismantlement of the spent bed material storage are considered. (author)