Combined PGET and PNAR System for Spent Fuel Verification

Year
2019
Author(s)
Mikael Moring - Radiation and Nuclear Safety Authority, STUK
Tapani P. Honkamaa - STUK - Radiation and Nuclear Safety Authority
Abstract
STUK is running national research and development project with the aim to create a national safeguards approach for the disposal project of spent nuclear fuel. Developing verification system which would meet recommendations of ASTOR groups of expert recommendations for verification prior spent fuel disposal is one of the main activities of the project. Together in cooperation with multiple stakeholders, STUK has designed a system which would meet ASTOR recommendations. The system is combination of two verification methods, namely Passive Gamma Emission Tomography (PGET) and Passive Neutron Albedo Reactivity (PNAR). PGET is approved method by the IAEA and will constitute a primary verification tool in the system. PGET is able to detect a single missing pin in the spent fuel assembly. Passive Neutron Albedo Reactivity (PNAR) is able to directly verify the presence of nuclear material in the fuel and also history and burn up of the fuel with certain accuracy. This paper presents integrated PGET+PNAR verification system, its projected application in Olkiluoto NPP in Finland and preliminary results.