3:15 PM - 3:30 PM
[1D03] Evaluation of the effect of random storage in clearance measurement containers on the radioactivity conversion factor (2)
Keywords:clearance, BWR, radiation, Ge semiconductor detector, Uneven distribution of density, Uneven distribution of source
In the decommissioning of Hamaoka Power Station Units 1 and 2, in order to apply clearance to the shredded metal scraps weighing about 1 ton in total, they are stored in containers, their radiation is measured, and then the radiation is converted into radioactivity. The contamination upper limit model to get the radioactivity, that sets the radioactivity conversion factor arranges contamination from the side with the smallest response function (cps/Bq), therefore it essentially overestimates the radioactivity. However, the conservativeness of the model could not be evaluated numerically because there was no calculation tool. Using the tool developed in this research, the following two cases were evaluated.
1) Uneven distribution of density is handled accurately within a realistic range (radiation sources are randomly arranged on the surface
2) The contamination upper limit model is used assuming that the bulk density is uniform inside the container
As a result, the conservativeness of this model was confirmed.
1) Uneven distribution of density is handled accurately within a realistic range (radiation sources are randomly arranged on the surface
2) The contamination upper limit model is used assuming that the bulk density is uniform inside the container
As a result, the conservativeness of this model was confirmed.