2021 Volume 70 Issue 12 Pages 381-391
A catastrophic earthquake of magnitude 9.0 occurred off the Pacific coast of Tohoku in Japan on March 11, 2011. The subsequent tsunami lost the cooling function of nuclear fuel at the Fukushima Daiichi Nuclear Power Station, resulting in a core meltdown. This is the outline of the Fukushima Daiichi accident. As an emergency action for fuel cooling, seawater was injected into the reactors and the spent fuel pools, resulting in various corrosion issues. This article first presents corrosion issues and mitigation activities immediately after the accident. Various corrosion mitigation methods that were examined for application to the reactors and the spent fuel pools, their selection process, the timing of application, and the result of application are described in detail. After the accident was resolved, the decommissioning work of the Fukushima Daiichi Nuclear Power Station is proceeding based on four technical issues: fuel removal from the spent fuel pools, fuel debris retrieval, contaminated water management, and waste management. This article also outlines the corrosion issues that have become apparent in solving these technical issues and the potential corrosion issues that may emerge in the future.
