Corium

Chernobyl Corium

Corium....it sounds like the name of an element that you never learned about in chemistry class.  But its not an element at all; its a slang term in the nuclear industry for the "lava" that a reactor's core turns into after a meltdown.  Here's two photos of corium from previous infamous incidents.  First from the basement of Chernobyl:

Molten Uranium Fuel from Chernobyl called th "Elephant's Foot"

And second, here's what Three Mile Island looked like after the meltdown:

Three Mile Island after Meltdown

Since we have no photos of the Fuksushima cores which have melted down, we must presume they look something like this.   While the reports have so far have admitted "partial meltdowns" in reactors 1,2,3 and 4 (spent fuel pool), US Energy Secretary, Nobel Laureate Stephen Chu has now reported that reactor #1, (whose building exploded March 13) underwent a 70% meltdown. I wonder if he has actually seen a TEPCO photo of the reactor that is still being kept from the public?
Update:  NY Times reports that this info came from modeling of the meltdown(s).

Question for the day:  "At what point does a partial meltdown become a total meltdown"?  We've been told that a total meltdown is a much more serious event likely to result in much larger radiation release.  What then are we to make of a 70% meltdown?  And if reactor 2 and 3 underwent a 99% meltdown, would this still be considered "partial"?   How is that different from what has actually happened?

There's more evidence of sporadic re-crtiticality, that is, the reactors turning themselves on. This video mentions a  blue glow possibly due to ionizing radiation or (if under water) Cherenkev Radiation. Also I've found an excellent new site:

http://fairewinds.com

It contains videos by a guy who used to be in the nuclear power plant industry.  The April 3 video there presents the evidence for re-criticality.  I learned some things from this site's videos:

• Unlike, gamma, beta and Alpha radiation,  neutrons (produced by criticality) are hard to detect, and not being searched for extensively. Heck, TEPCO didn't even protect their workers with cheep  dosimeters.
• Those towers you see in the pictures are not ariels for radio transmission.  They were intended do disperse radioactivity high up in the air, but failed miserably after power went out.  This might be a good thing as this may have kept the radiation close to the ground.