3. Stabilization of the situation from the accident to the end of 2018

During the events described above, the cores of reactors 1, 2 and 3 at the Fukushima Daiichi nuclear power plant melted, and the buildings of reactors 1, 3 and 4 underwent major explosions, causing significant damage to their structures.

However, the situation was gradually stabilized by the operator, and none of the reactors permanently lost cooling after March 15, thanks to the injection of seawater until the end of March, and then fresh water.

Power supplies were gradually restored from mid-March onwards.

Provisions are then put in place to ensure long-term control of the facilities, so that the actions required for their complete dismantling can be carried out under satisfactory safety conditions. A key concern is to control releases, given the degraded state of the facilities' containment and the quantities...