Preliminary calculation with JENDL-4.0 for evaluation of dose rate distribution in the primary containment vessel of the Fukushima Daiichi Nuclear Power Station

Okumura, Keisuke 

For the decommissioning of the Fukushima Daiichi Nuclear Power Station (1F), it is important to know the dose rate distribution in the primary containment vessel (PCV). However the distribution of radiation sources in PCV is not clear yet. There are three kinds of radiation sources in PCV. They are fuel debris, structures in PCV contaminated with Cs emitted at the 1F accident, and activated structures irradiated during normal reactor operating before the accident. In order to establish the evaluation method of the dose rate distribution in PCV, a preliminary calculation was carried out with JENDL-4.0. As a result, the sensitivity of each source to the dose distribution was obtained.