The Next Generation Safeguards Initiative Spent Fuel (NGSI-SF)
Project deployed a non- destructive assay (NDA) Passive Neutron
Albedo Reactivity (PNAR) system to measure the heavy-water
moderated, light-water cooled Fugen reactor fuel assemblies in June
2013. The NDA system combines the following NDA techniques: ( 1)
PNAR, (2) total neutron, (3) total gamma and (4) three sets of
fission chambers. Each set of these fission chambers is surrounded
by different materials to detect neutrons in differ ent energy
ranges. The measurement results of the four NDA techniques included
have been analyzed and compared to Monteburns simulations of the
Fugen fuel assemblies to assess the measurement capabilities of the
PNAR system. Photon measurements matched the photon simu lations
performed by the Fugen plant well. PNAR measurements showed a
change in the PNAR signal that trended with multiplication. Future
plans with this instrument will include measuring a variety of
fresh fuel assemblies comprised of differing numbers of low-en
riched rods (3.2%, 0.7%, and 0.3% pins, as well as 3.2% pins with
Gd) at Los Alamos National Laboratory. These experiments will be
performed in water and be driven by neutrons from a Cf source
placed inside the assembly.
- J. Eigenbrodt, S.J. Tobin, W.S. Charlton, A.M. Bolind, H.O. Menlove, M. Seya, and H.R. Trellue,
"PNAR Measurements of Fugen Fuel,"
55th Annual Meeting of the Institute of Nuclear Materials Management, Atlanta, Georgia, 20-14 July 2014.
- J. Eigenbrodt, W. Charlton, H.O. Menlove, S.J. Tobin, M. Seya, H.R. Trellue, A.M. Bolind,
"Simulations and Preparation for PNAR Measurements of Fugen Fuel,"
Proceedings of the 35th ESARDA Annual Meeting, 27-30 May, 2013, Bruges, Belgium.
View of Fugen NPP (Source: Japan Ministry of Land, Infrastructure and Transport)