Yet again, I must apologize for neglecting this blog. I've been quite preoccupied with my research. I finished up my time in Washington a few weeks ago and have now moved to Kiev for the summer to study in the archives here. I've tracked down some very interesting documents about Chernobyl that I will be using as part of my dissertation. I really wish I could photograph these things and post them on the blog, but unfortunately the archive they are in doesn't allow photography. For instance, the include reports made for the Communist Party about the radiation level in Kiev and other Ukrainian cities after the accident.
I've also been hesitant to comment on the still-developing situation in Japan, in large measure because detailed, accurate information seems so hard to come by. Until the accident sequence is nailed down, trying to draw concrete "lessons" from the events there will be a fool's game. At the moment TEPCO is claiming that the earthquake was not the cause of the failures at Fukushima Daiichi units 1-3, and that the tsunami alone resulted in the deplorable outcome there. This is hotly contested by some, however, who claim that the emergency core cooling system in unit 1 failed prior to the tsunami. Even if this were the case, the availability of auxiliary power in the absence of the tsunami would presumably have allowed the operation of the standby gas treatment system and prevented the hydrogen explosion as well as captured most of the volatile radioisotopes, so the end result would probably have been far less dire.
The great mystery to me is what happened in unit 4, which experienced damage to the refueling floor blow-out panels. Back in March it appeared that somehow the water level in the spent fuel storage pool in unit 4 had grown so low as to expose the fuel, resulting in the zirconium-steam reaction and the creation of large amounts of hydrogen. But TEPCO images of the unit 4 pool show that the fuel is basically intact. It's supposedly implausible that radiolytic alone hydrogen production could have had the observed result; one possibility is that hydrogen from unit 3, which apparently shared a ventilation stack with unit 4, backed up into unit 4. Presumably what actually happened will become clear as efforts to stabilize the plants continue.
In July I'm planning on a return trip to Chernobyl, which should hopefully include some sites I missed out on last time. I'm also trying to arrange a visit to an operating VVER plant here in Ukraine, but no definite word on that yet. Hopefully I'll have interesting things to say about it.