Page 22 - Treactor Core News Today : Breaking News, Live Updates & Top Stories | Vimarsana

Doomsday. martha raddatz puts all those fears in perspective. >> reporter: how bad could it get? the big fear is nuclear meltdown. meaning the reactor core gets so hot, it turns into a radioactive molten mass, breaking through the containment vessel, spewing radioactivity through the air, ground and water. in the hollywood "china syndrome" version they claim the mass could melt through a steel floor, through the earth, to china. no one thinks that could happen. but the reality for japanese reactors? >> this is way past three mile island and we're heading into chernobyl territory. >> reporter: ...

Four reactors there. here's what we know. reactor one exploded saturday, destroying the outer building but leaving the core intact. number two exploded yesterday, damaging steel walls containing the reactor core. an explosion in number three also damaged the containment building. potentially radioactive steam is venting from both of those reactors. and a fire broke out at reactor four today. the worry there is that the spent fuel rods being stored above the core will overheat. with me now, david albright, president of isis which specializes in global nuclear activity. david, it's great to have...

So basically what we do know at the very basic level this problem seems inside the reactor got too hot. earlier tom foreman explained to anderson cooper how this particular crisis is playing out looking at the mechanics of how a reactor overheats. >> this is from nhk on japanese television. essentially what you had was this reactor core started heating up after the accident, the pumps kicked in that are supposed to cool it down, but then they had an electrical failure and the pumps went dead. so a bunch of diesel pumps kicked in then, and they were running, then they went dead. not yet clear w...

Right here. this is coming to us from nhk, which is japanese television. this is what is supposed to happen. water pumps in. it cools the reactor rods in the reactor core. after the tsunami, unfortunately, that power source became lost so they went to their diesel-powered backup reactor. the diesel pumps kicked in and eventually they failed. then go to their battery pumps but unfortunately the battery pumps only continued working a number of hours and they also went dead. why that happened is still not exactly known. the problem is as the water source slowly starts to end, you have the buildup...

So you get a sense of the scale. but here's what's interesting, anderson. this has been a series of failures from the beginning. this is from nhk, the japanese television. essentially, what you had was this reactor core started heating up after the accident. the pumps kicked in that are supposed to cool it down. but then they had an electrical failure. and the pumps went dead. so a bunch of diesel pumps kicked in then. and they were running. and then they went dead. it's not yet clear why. maybe the tsunami did this. then another set of battery pumps kicked in. they worked for a while and then...