EVALUATION STUDY OF MICRO PARTICLE GENERATION OF FUEL DEBRIS DUE TO CHEMICAL AGING AT FUKUSHIMA DAIICHI NUCLEAR POWER PLANT

Abstract

The understanding of long-term stability of fuel debris (FD) is one of the most important issue for reduction of radiation exposure due to micro particle generated from FD during Fukushima Daiichi decommissioning. The objective of this study is to investigate the probability of long-term aging of FD under decommissioning environment. Nine types of samples which simulate FD considered to exist in the Primary Containment Vessel (PCV) were fabricated, and underwent air exposure tests and water immersion tests to evaluate the probability of micro particle generation due to chemical aging under the environments exposed in the PCV interior, or during the retrieval and storage operation. The experimental results revealed particle generation occurred on specific FD material type and environmental condition.