Japan and Fukushima 3 years after the tsunami

After a comment of aerial photographs of the Fukushima region after the tsunami, and some observations about the condition of the different reactor buildings of the power station, the author recalls some design and architecture characteristics of Japanese BWR reactors and outlines some peculiarities, notably the absence of secondary circuit. He discusses the accident process, the issue of residual power, and how explosions occurred. He describes the situation 3 years after the accident by giving indications on the status of the reactor: its residual power, its core temperature, and water injection. The main tasks to be performed have been: to safely stop the reactors, to remove radioactive debris, to decontaminate the site, to manage waters, to restore confinements, to remove the numerous (more than 12.000) more or less molten fuel assemblies, to manage contaminated waters. The author discusses the issue of underground waters. He addresses the issue of site dismantling with its different steps which are planned over 40 years. While recalling the Japanese regulation in case of nuclear accident, and proposing a map from the evacuation plan with its different areas, the author recalls the initial area evacuation timing during the first weeks. He indicates the evolution of radioactivity for different radionuclides, evokes the issue of storage of contaminated soils and plants. He addresses the issue of dosimetry and of the health impact (regulatory levels, staff dose levels), the issues of food products and internal doses and the opinion of the HWO on the health impact, and the issue of a return of populations. The status and condition of nuclear energy in Japan is evoked