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Crack In Fukushima Structure May Be Leaking Radiation
SillySnake writes with this excerpt from Reuters: "Tokyo Electric Power Co (TEPCO) said it had found a crack in the pit at its No.2 reactor in Fukushima, generating readings 1,000 millisieverts of radiation per hour in the air inside the pit. 'With radiation levels rising in the seawater near the plant, we have been trying to confirm the reason why, and in that context, this could be one source,' said Hidehiko Nishiyama, deputy head of the Nuclear and Industrial Safety Agency (NISA), said on Saturday."
Also of interest: Cryptome is featuring high-res photos of the reactor site, taken by UAV.
Crack In Fukushima Structure May Be Leaking Radiation
I skimmed TFA and it seems the "may" was introduced by /. editors and not the evil "mainstream media". There is a leak and it is radioactive water that it is leaking. No maybe. Actually they already planned how to fix it , tried to do so and failed at it.
I think it's been handled pretty well. Nobody has been killed by DEADLY ATOMS, and the only radiological injuries have been skin burns to two workers who ignored their dosimeter alarms. The release of radionuclides into the air has been minimal, and the amounts found in food and water have dropped back below minimum levels in all but the immediate locality to the reactor complex (and the levels there are only above the 'constant yearly exposure' maximums). Reactor core and storage pool temperatures are again under control, and coolant water containment in all but two reactors is unbreached. In one of those, the leak of irradiated coolant is within the reactor complex.
The 'crack' mentioned in this case is not in the reactor containment itself as the summary and article imply, but in a water storage pool next to the sea, with the crack being between the pool and the sea.
Not that lessons can't be learnt from this: gravity-feed coolant reservoirs would be a good idea, as well as separate backups for the storage pools and cores, but it's far from "getting steadily worse".
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NOTE: This post is mostly recycled from a previous post at the bottom of a thread under the previous Fukushima story. The thread started with a post I made warning that most of the radioactivity leaking from Fukushima was moving downward into the ground and ocean, not upward into the air.
Filling the crack and fixing this leak won't reduce the amount of radioactive material spewing from reactor #2 into the environment. This pit and the concrete with the crack in it were never intended to be part of the containment system. If they succeed, then the HRW (highly radioactive water) will either (a) find another way into the sea, or (b) further contaminant the groundwater, or (c) flood the ground and then do (a) or (b). Depending on the total amount of radioactivity released, it *might* actually be better to pour this HRW into the ocean where it will be diluted down to safe levels.
The term "containment" has a fairly precise technical meaning (BTW: I've got a Ph.D. in nuclear physics but not nuclear engineering). These reactors are basically a bottle in a bottle. The inner bottle is the pressure vessel and it is used to maintain pressure for the creation of steam and electricity. The outer bottle is 10cm or 20cm thick stainless steel. It is called the containment vessel. Its sole purpose in life is to contain all the radioactivity in the event the fuel rods melt down. Normally almost all the radioactivity is contained in the zirconium clad fuel rods. That is why there can be HRW 100,000x higher than the water found in a functioning reactor. Almost all of the radioactivity in a functioning reactor of this type is contained in the fuel rods. When the fuel rods melt down, high levels of radioactive materials contaminate the water making it highly radioactive.
Up until last week, the word "containment" had the simple and obvious meaning of radioactive materials staying inside the massive stainless steel containment vessel. I believe TEPCO forged a new meaning in order to downplay the significance of the HRW that was found in the turbine buildings. I will use the traditional technical definition, not the new one invented by TEPCO.
You see, the idea was that as long as the radioactivity was kept inside the containment vessel then you could safely operate the plant and move around in it. The environment was safe. The control room was safe. The turbine building was safe. Even the reactor building was safe (as long as you stayed out of the containment vessel and storage pool). Everything was safe. One of the difficulties caused by a loss of containment accident is that it becomes difficult and dangerous to work on the plant. That is why they need to pump out the turbine buildings before they work on restoring the cooling. If they hadn't lost containment (in the traditional sense) this would not have been a problem.
The pit, the tunnels, and even the turbine buildings were not designed to contain radioactivity. The buildings were designed, like most buildings, to keep the rain out, etc. For example, right after they had those scary hydrogen explosions that blew apart the reactor buildings, I was assuring people it was not a big deal because those buildings were never designed to contain radioactivity. TEPCO and the government were offering the same assurances.
When I heard about the HRW in the turbine buildings I stopped issuing reassurances and I started to be greatly concerned because it meant they had lost containment. I was hoping against hope that the HRW in the turbine buildings was a fluke and that it hadn't spread elsewhere. When I then then heard the tunnels outside the turbine buildings were flooded with HRW I knew this was a serious accident, much worse than Three-Mile Island. When I heard there were 18,000 tons of HRW outside of containment (that number has now been reduced to 13,000 tons) I knew this was a big fucking deal and I was surprised that the Western press were ignoring these developments even though they had been h
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