It’s a triple meltDOWN. Throwing a concrete blanket over it won’t help stop hot liquid radioactive sludge from oozing/burning thru dirt and seeping into the ocean to the tune of 300 tons of radioactive water per day.
It’s not burning anything any longer. Now the rods that had burned through the containment are sitting in groundwater that is leaching through It and being carried into the Pacific. There was talk of trying to create a frozen zone around it.
I was thinking that volume of water would find its way out no matter how far out you could effectively poor a barrier.