From this photo I think we can assume that the environmental shield is gone, and all the control systems, pumps, turbines etc used to remove the heat in the reactor core in a controlled fashion are gone as well (thrown hundreds of metres either side of the environmental concrete shield, which itself was basically turned to dust) and the reactor containment shield is breached with the reactor core is well alight.

So much for the vested interest commentary from the media news nuclear experts and the information from the Japanese Government pretending that what has happened today doesn't even warrant a more dangerous accident than the 3 mile island incident.

If the wind changes how do you evacuate 40 million from Greater Tokyo Yokohama urban area 120 miles away. I guess the answer is that you can't.