浜岡原子力発電所5号機における海水流入事象に係る原子炉圧力容器廻りの浄化・保管について
概要
In the process of achieving cold shutdown of Hamaoka Nuclear Power Station Unit 5 on May 14, 2011, sea water flowed into the reactor and other equipment due to main condenser tube leakage. By clean-up operation, chloride ion concentration went below 10 ppm, the target prescribed to prevent crevice corrosion. On Dec, 2015, the component health assessment had summarized by surveys focusing on material corrosion, deposit and residual chloride. Since, each equipment have been under wet or dry lay-up condition. As a result of review of lay-up method by inner surface inspection, equipment under each lay-up condition have no significant corrosion and no significant deposit, as so far. The system health assessment conducted before re-start will confirm appropriateness of lay-up.
