A Study on measurement and evaluation method for radioactivity concentration distribution of recycled materials from contaminated debris

Shimada, Taro ; Takai, Shizuka ; Takeda, Seiji 

In order to recycle contaminated debris of which concentration is relatively lower in Fukushima Daiichi Nuclear Power Station, it is necessary to confirm that the mean radioactive concentration is lower than a reference value with consideration of the distribution by measurement and evaluation. We studied a method combining radiation measurement and inverse analysis to obtain the distribution of radioactivity concentration of recycled material. Plastic scintillation fiber will be applied to radiation measurement to obtain dose rates outside the container containing recycled material at many measurement points. As a result of application of 7 inverse analysis methods to typical two types of distribution, GVSPM and ML-EL methods can evaluate true values in the trials.