Reactor containment breached.
Meltdown has occured.
IMO, GET EVERYONE OUT OF THE AREA FROM A MINUMUM OF 10 MILES RADIUS. NOW.
It's time to consider using a small yield tactical nuke to vaporize and destroy the remaining reactors, the fuel rods and the plant.
Otherwise the meltdown (core) will continue to spew radiation into the air, water and ground for years.
Better to stop it now and have the fallout contained locally than to have the radiation carried throughout the world for years on the wind and ocean currents.
This may be the only remaining option... if a meltdown continues, it will not be contained by sealing it in concrete and sand from above.