Nuclear Material Monitoring for the Reprocessing Plant RT-1 at Mayak

To enhance and modernise the Nuclear Material Accountancy and Control (NMAC) at Mayak RT-1 reprocessing plant the concept of near real time accountancy (NRTA) is applied. A defence in depth concept is proposed with the superposition of the following barriers: (i) continuous survey of the functional status, (ii) the follow-up of the nuclear material (NM) flow and inventory, (iii) Near real time control of declared NM in processed solutions, (iv) Periodical Physical Inventory Takings and Verifications. The combination of an operational network architecture, allowing automatic data acquisition and an efficient plant-specific data analysis and interpretation software enables to follow in near real-time the NM flow and inventory through the plant. The JRC data analysis and interpretation kernel DAI integrated with the commercial data historian Wizcon is proposed to establish the RT-1 specific NM monitoring software tool. The data analysis focuses firstly on a combination of the pressure signals (for level and density) and the temperature signal, determining the total volume. This is then combined with the volume concentration measurement performed by the hybrid K-edge to derive the total mass of nuclear material. Once the complete system is validated, it can be applied also to other Russian reprocessing plants at Seversk and Zheleznogorsk.JRC.G.8-Nuclear safeguard