"They are worried about the enormous quantities of water, used to cool the reactor cores, which are now being stored on site.
Some 1,000 tanks have been built to hold the water. But these are believed to be at around 85% of their capacity and every day an extra 400 tonnes of water are being added."
Probably they are still cooling down the reactors, as least somewhat. The effect is called "decay heat" and does take quite some time to completely dissipate for reactors of that scale.
However there is also a lot of groundwater leaking into the basement/reactor complex apparently, which then needs to be pumped back out.
Some 1,000 tanks have been built to hold the water. But these are believed to be at around 85% of their capacity and every day an extra 400 tonnes of water are being added."
Are they still cooling down the reactors?