Characterization of radiation release from PWR spent fuel assemblies

J.H. Moon

Spent nuclear fuel should be kept under safe and strict management until they can be disposed of permanently. For this, it is important to understand the radiation release characteristics from the spent nuclear fuel. In this paper, hence, Monte Carlo method is applied to evaluate 2 types of PWR spent fuel assembly generated from the operating plants in Korea: Westinghouse- and KSNP-type. The source terms were calculated using ORIGEN-ARP. The neutron and photon (or gamma) dose distributions along the vertical and horizontal directions of the fuel assembly were evaluated using MCNPX code. Compared with the 2 dose distributions, the photon dose was found to be about 105 times higher than the neutron dose.