By now you all know the story. The video has to be seen to be believed. Sendai looks like a G--d---- nuclear bomb hit it -- unbelievable devastation. Our family and friends in Japan are all accounted for and safe, thank God, but as a survivor of a major earthquake myself (Northridge '94, 6.6) I can guarantee you they are scared. (Our Yuki is here in the USA, in Orlando, so she's safe.)

For continuous live steaming video, open NHK in a window and let it run. The shibō/fumei counter inset into the video image is bone-chilling, like Hell's scoreboard. As you monitor, keep an ear open for the phrase genshiryoko hatsuden-sho [原子力発電所, "nuclear power plant"]. They lost coolant pressure at the big plant near Sendai today. I'm a  former nuclear power worker, and let me tell you that's a sphincter-clenchingly scary situation. For a reactor that big (1100 MW) to lose all coolant pressure to the core is a nightmare scenario. Fortunately it's an BWR (boiling water) type reactor, so even if the core runs dry it can't melt down Chernobyl-style; without water in the core to thermalize (slow down) the neutron flux from the rods, the reaction stops (steam being more or less neutron-transparent, stopping criticality in the core).

Unfortunately, if coolant flow stops, whatever is left in the reactor core is going to flash to hot steam at high pressure (about 500°F @ 1100 PSI) and it's gotta go somewhere. I guarantee you that they will vent the core to secondary containment (the reactor building and control areas, basically) to save the core and pipes from rupturing, and that building isn't airtight; some radioactive steam will get out (if it hasn't already). Result: the control room and everybody and everything in it are going to end up being contaminated.

And they are going to have to dump the steam in the containment building sooner or later Radioactive steam on top of the Hiroshima-level destruction... not pretty.

Give money to relief organizations if you can. Otherwise, please pray for the folks in Japan who are hurting tonight. There's really nothing else to do.


Anonymous said...

Thanks for posting that, Bruce.

I'm really at a loss for words; The footage coming in yesterday morning (and today) is just unbelievable.

Been saying more prayers than usual, but this is still unlike anything I've ever seen in my lifetime.


Bruce Lewis said...

The containment at Fuku #1 gave out this morning. My guess: hydrogen gas explosion (hydrogen gas is a catalytic byproduct of the reaction of steam and the zirconium cladding on the fuel elements). Blew the whole damned roof and all four walls off the building top like a bursting balloon. Fortunately there is no fire and the criticality naturally damps in a BWR type core, so as long as the reactor vessel itself maitains integrity you're only going to get some low-level contamination from fission byproducts condensed out of the vent gases. Still, a dicey situation. Several other reactors are in trouble and they evacuated a 20km circle around F#2 this morning our time, so things are still pretty scary...

Anonymous said...

I just heard Matt Alt on CNN.


Anonymous said...

Also, they updated the earthquake from 8.9 to a 9.