TEPCO Rose

[FBaggins]

19. I hope she doesn't know it...

... because it isn't even close to true.

Some of the nuclear core material from 3 reactors at Fukushima have exited containment

Put it that way and you're correct... some of the material (e.g., the most volatile) escaped from containment either in gaseous form during venting, or carried in water that leaked out of the containment.

The problem is... you never stop with that. You move on to:

You do know that some pieces of core material were found miles away and some has melted into the ground underneath the cores.

This simply isn't true. There haven't been chunks of core material found miles away... there has been fallout contamination (e.g., cesium) that clearly had to have come from the core... but not solid pieces of core ejected in an explosion. Nor has there been any evidence that any core material has "melted into the ground". All of the available evidence indicates that whatever corium is not still in the reactor vessels, is sitting on the floor of the primary containment.