Determination and verification of the scaling factor for the radionuclide inventory of the radioactive waste from nuclear power plants

Abstract

The Database of the first Scaling Factor for the radionuclide inventory of the radioactive wastes from the nuclear power plant (NPP) in Korea was obtained in 2005, which consists of the ratios of the radioactivity of Difficult-To-Measure (DTM) radionuclides to key gamma nuclides such as 60Co and 137Cs. The Database of the SF has 255 of radioactivity data on 6 waste streams from 20 NPPs. If the SF can be applicable to any wastes regardless of their generation year, then it can be applied all over the wastes from the past NPP wastes to the future ones. For the purpose, KHNP has planned to obtain the second SF through 337 samples from the same wastes as the first ones from 2007 to 2008. The second SF will be a principal key to verify the validity of the first SF for Korean NPP wastes. The first and the second SF will be unified to one SF in case of completion of verification. The wastes produced before the first SF was derived also have to be verified that it has the same correlation to the unified SF. In this study, 8 solidified evaporated bottom waste drums produced from 1988 to 2003 were cored and the radioactivities were analyzed. The SFs were compared with the first SF and proved that the SF can be applied all over the wastes from the past NPP wastes to the future ones in case of the solidified evaporated bottom waste drums.