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Terrifying Video of Nuclear Plant Explosion In Japan
Brian Barrett — At 3:40pm local time in Japan's Fukushima Prefecture, an explosion shook the Fukushima Daiichi nuclear plant. Four people were reported injured from the initial blast, but broader concerns over increased radiation leakage have lead officials to double the evacuation zone around the plant from 6 to 12 miles. What the ultimate fallout will be is anyone's guess.The Daiichi plant is one of the two that experienced cooling failureearly after yesterday's devastating quake, and was teetering on the brink of a meltdown just hours ago. According to Tokyo Electric Power Company, the explosion happened "near" but not in the Unit 1 reactor. Radiation levels had reached 1,000 times above normal in a reactor control room at the plant, and more troublingly levels had reached 8x normal near the main gate.
The important thing, though, is that it appears that the explosion—likely caused by a hydrogen build-up—only affected the wall around the reactor and not steel container housing the reactor itself. The important thing now is that cooling operations continue unhampered. If the cooling systems are inoperative for several hours, the reactor's water will boil away and the fuel will begin to melt. When that happens, the situation escalates from "manageable" to "Three Mile Island." And while there are indications that radiation levels have in fact declined since the explosion, Daiichi is still currently walking that line very tightly.
The International Atomic Energy Agency is providing real-time updates on Daiichi on its Facebook page. We will as well as the situation warrants. [Russia Today, NY Times]
This is a light-water reactor, those tend to not explode if there is a meltdown. The core itself is intact, and they are pulling out all the stops to cool the core down until they can get the normal cooling systems back online. I wouldn't call the danger over yet, but it's fairly safe to assume that the situation is now under control to a large degree.
Every country with knowledge in this field is already assisting the Japanese as needed, so I'd say you should be ok. :)
If you feel like making outlandishly extreme comparisons, please at least restrict them to Three Mile Island. The worst reactor meltdown in US history! But before you do that you should also know that that reactor is now over half a century old and is still 3 years away from retirement. The land around it is no longer irradiated and the area has been deemed safe. The moderate levels of radiation in the area did take the better part of 2 decades to clean up, but only because any remaining radiation levels outside of the day to day noise is bad. To give you an idea: the peripheral evacuation of the land surrounding three mile island was termed as "voluntary".
So no, this is not Chernobyl, and not, yet, a Three Mile Island. Considering that it was a close 9.0 on the Richter scale they're doing a damn fine job overseas.
And no, we don't have crap to worry about here...
Most of them are in fact American, and this isn't the sort of emergency that happens frequently (thank goodness for that). So any assistance is probably welcome, although they will undoubtedly have had many contingency plans ready to go in case of a disaster.
They are currently flooding the core with seawater to cool it down, and that will then serve as the coolant until the main cooling systems can be brought back up. Not a perfect solution, but quite effective, there's plenty of ocean to pump into that core.
Any more serious after shocks, and halt in the cooling process and if they don't get their main systems back and running then yes you are looking at another nuclear meltdown.
The reactor is hot as hell, but holding, and the situation looks under control indeed.
Improvements have been made over the years, naturally, but as it stands, nuclear power is probably the cleanest and safest power-source we've got until other options are made more efficient.
As for the other plants, most don't have their manufacturers mentioned. A few do, especially the new ones, and most of those appear to be from Hitashi, but beyond that it's not clear.