The JAEA Part of the Joint JAEA-U.S. DOE Project for Pu Measurement of Fugen Spent Fuel Assemblies by Integrated PNAR and SINRD

The Fugen advanced thermal reactor was a prototype nuclear reactor in Tsuruga, Fukui, Japan, that was moderated by heavy water but cooled by light water. It produced 165 MW of electrical power from 557 MW of thermal power. Fugen’s heavy-water moderator enabled it to run on a wide range of mixes of MOX and UO2 fuel assemblies, from 34% MOX to 72% MOX. (The fissile enrichment of the MOX and UO2 was about 1.5% to 2%, depending on the fuel assembly type.). It stopped operations in 2003 and is now being decommissioned. Nevertheless, the spent-fuel pool at Fugen still remains and currently contains both MOX and UO2 spent-fuel assemblies. Because Fugen was a prototype, the standard operations at the spent-fuel pool are flexible enough to be able to conduct NDA experiments on the spent fuel. Therefore, JAEA and the USDOE are planning to conduct a test of an integrated PNAR and SINRD NDA measurement system at Fugen in 2013. LANL is designing and constructing the detector, and JAEA is preparing the Fugen site for the test. The total experience of preparing for and conducting an NDA measurement on actual spent fuel will teach important lessons about the practicality of applying such measurements in the future to spent fuel assemblies from commercial LWR power plants, especially with regard to satisfying legal and safety requirements.