Once a severe accident occurs, to estimate the future behavior and risks of the plant, it is important to know the real-time fuel information such as decay heat and nuclide inventories, which is usually different from the safety evaluation with conservative conditions. In order to fulfill this requirement, Mitsubishi Heavy Industries, Ltd. (MHI) has been developing a fuel management system - M-SAVIOR, which analyses and manages the real-time fuel information such as source term, decay heat and radioactivity. Nuclear power electric utilities and their fuel suppliers have to manage the holding uranium and plutonium inventories properly as the accounting records. Using our new system, the nuclides relating to radioactivity can be added to the accounting records easily and consistently with the uranium and plutonium inventories presently maintained. In this paper, we describe our new system - M-SAVIOR and its evaluation method of the individual fuel information.
