Since TEPCO is using seawater for many of its cooling needs at the power plant, it has previously encountered heightened levels of corrosion, in sensitive equipment. The cooling system at various reactors has also been beset by calamities – from rats short circuiting the control panel and forcing a blackout, to an employee “accidentally” switching it off, though all were resolved before rod pools overheated.

At the same time, TEPCO is struggling to deal with ever-increasing volumes of contaminated water which is being stored in hundreds of tanks at the facility and frequently leaking and contaminating the soil beneath it. And the much publicized plan to stop contaminated water from leaking into the sea by building an ‘ice-wall’ and freezing soil and water around the facility is not working as well as Japanese officials had hoped.

^^ Yeah it was a total failure, because it WON'T FREEZE.