Fukushima-Daiichi plant data analysis focusing on core material relocation to pedestal

Sato, Ikken; Yoshikawa, Shinji

no journal, , 

In Fukushima Daiichi Nuclear Power Station Units 1-3, some part of the core materials including fuel relocated through the reactor pressure vessel (RPV) into the pedestal area. As a result of comprehensive analysis of data such as pressure gauges and water level gauges,it was evaluated that the time duration of the core material relocation to the pedestal was, less than 0.5 hr for Unit 1, around 2.5 hours for Unit 2 and around 7 hours for Unit 3 respectively.