Radiation Leak Feared at Fukushima No. 2 Reactor
The crisis at the quake-hit Fukushima No. 1 nuclear plant reached a critical phase Tuesday with high levels of radiation feared to have leaked after apparent hydrogen blasts at two more reactors, triggering growing fears of widespread contamination.
Prime Minister Naoto Kan urged people living between 20 and 30 kilometers of the plant to stay indoors, after radiation equivalent to 400 times the level to which people can safely be exposed in one year was detected near the No. 3 reactor in the plant.
The government's Nuclear and Industrial Safety Agency said that radiation levels at the plant shot up after an apparent blast at its No. 2 reactor
Japan PM: Radiation leaking from damaged plant
Radiation is spewing from damaged reactors at a crippled nuclear power plant in tsunami-ravaged northeastern Japan in a dramatic escalation of the 4-day-old catastrophe. The prime minister has warned residents to stay inside or risk getting radiation sickness.
In a nationally televised statement, Prime Minister Naoto Kan said radiation has spread from the three reactors of the Fukushima Dai-ichi nuclear plant in one of the hardest-hit provinces in Friday's 9.0-magnitude earthquake and the ensuing tsunami. He told people living within 12 miles (20 kilometers) of the plant to evacuate and those within 19 miles (30 kilometers) to stay indoors.
"The level seems very high, and there is still a very high risk of more radiation coming out," Kan said.
Japanese officials had previously said radiation levels at the plant were within safe limits, and international scientists said that while there were serious dangers, there was little risk of a catastrophe like Chernobyl in Ukraine, where the reactor exploded and released a radiation cloud over much of Europe.
Unlike the plant in Japan, the Chernobyl reactor was not housed in a sealed container to prevent the release of radiation.
Explosion and Fire at Fourth Japanese Nuclear Reactor...Government Says High Levels of Radiation Being Released
RADIATION levels near a quake-stricken nuclear plant are now harmful to human health, Japan's government says after explosions and a fire at the facility.
"There is no doubt that unlike in the past, the figures are the level at which human health can be affected," said chief government spokesman Yukio Edano.
Radioactive levels 10 times above normal near Tokyo
IAEA reports fuel pond fire that released radioactivity into atmosphere was extinguished; News agency says fuel pond at No. 4 reactor boiling.
There have been a total of four explosions at the plant since it was damaged in last Friday's massive earthquake and tsunami.
Authorities had previously been trying to prevent meltdowns in three of the Fukishima Daiichi complex's nuclear reactors by flooding the chambers with sea water to cool them down.
The following article is yet another explanation of why the nuclear plants in Japan may not mimic Chernobyl as some are predicting:
Fear the Media Meltdown, Not the Nuclear One
This article contains a lot of details regarding the plant design and offers more information that most articles circulating right now:
The Fukushima plants have several reactors built on the same basic design, either by GE or by Japanese companies licensed by GE. These are all “boiling water” reactors, which means just what it sounds like: the heat of the nuclear reaction boils water; the steam generated is used to drive turbines and thereby generate power.
The water in direct contact with the reactor core known as “coolant” is nothing particularly special, just demineralized; water itself isn’t very susceptible to becoming radioactive, but minerals and contaminants in the water can be. If the water is purified, there’s less radioactive waste to deal with.
The cooling water is pumped past the reactor core in normal operation to get the energy with which power is generated, and of course to cool the core. If there’s an accident, the reactor is shut down by inserting the “control rods,” made of some material that absorbs neutrons and so slows the nuclear fission from which the reactor gets its power.
Even a shut down reactor continues to need cooling, however; there’s an immense amount of residual heat still left in the reactor core. This means continuing to run the pumps, and of course with the reactor shut down they can’t be run from the reactor’s power, so there are diesel generators as a backup, and batteries as a further backup to the generator.
If all the cooling fails for some reason, the accumulated heat can’t escape; the water boils away, and once it’s gone, the materials that make up the reactor core break down. This is a Bad Thing, because the controls on the reactor fuel also break down; it starts to heat up again. This is what’s called a meltdown.
When this happened at Chernobyl, the reactor core quickly became hot enough to vaporize the reactor’s fuel and a good part of the other material around it, leading to an explosion that destroyed the building that housed the reactor.
That represents the background. Now the article takes up to the current situation in Japan:
The original earthquake hit. Three of the six reactors were in operation, the other three were shut down for scheduled maintenance. The reactors were designed to sustain an earthquake of magnitude 8.2; at magnitude 9, the Honshu quake was 16 times more powerful. This caused the plant to automatically shut down; this was apparently successful, but …
About an hour later, the tsunami hit. The tsunami did two significant things: it destroyed the backup generators that kept the pumps running, and it apparently so contaminated the reserve coolant that it was not only no longer pure, but was so mucked up with the scourings of the tsunami that it couldn’t be safely pumped. At this point, the reactor was in some trouble
As the reactor heated up, water began to react with the zirconium fuel-rod containers, liberating hydrogen, which started to build up in the boiler. The operators began to vent gases from the reactor to reduce the pressure, liberating the hydrogen into the outer façade building.
These gases are mildly radioactive, mainly with nitrogen-16 and several isotopes of xenon, all products of the fission reaction that powers the reactor; apparently they were vented into the outer building in order to slow their dispersion and give them a chance to lose radioactivity.
Misinformation:
Television talking heads talked about the “containment building.” Which is strictly true, since the building in which the containment is housed would be the “containment building” — but misleading and confusing, because the containment for all three reactors remained intact.
So there’s the first bottom-line point: at least so far, the inner, steel, containment vessel on all three Fukushima reactors remains intact.
When the gases started to be released from the containment vessels, that meant there was some release of radiation. With their usual nuance, the media reported only that there was radiation released; since there was detectable radioactivity on the clothes and bodies of the men injured in the explosion, this apparently turned into “radiation poisoning,” even for the poor guy who had the heart attack.
After detailing the four major "experts" who are predicting doom and gloom and their lack of credentials, we see the conclusion:
No one can tell you that there will absolutely not be a catastrophic failure — really catastrophic, like Chernobyl or worse — at one or more of the Fukushima reactors. At the absolutely worst case, some combination of accidents and failures could break through all three major containments and release a large amount of radiation through the “China Syndrome” or something like it.
It’s very likely that there has been at least a partial meltdown in one or more of the reactors — but “meltdown” doesn’t mean “catastrophic release.” The reactor would not just have to melt down, but also penetrate both the still containment vessel and the concrete outer layer, and both were designed explicitly to keep that from happening.
What we can say is that it’s not very likely to be a catastrophic accident, and gets less likely with every minute. The Japanese are cooling the reactors down, and adding boron, which “poisons” the nuclear reaction by absorbing neutrons, the “sparks” that make the reaction go.
The amount of radiation that has been released is, so far, actually very minor. Instead of being “another Chernobyl,” which the IAEA put at INES level 7, this is INES level 4 — and Three Mile Island was level 5. So far, Fukushima is not just not another Chernobyl, it’s not even another Three Mile Island.
And finally, when you hear someone in the media giving one of these catastrophic predictions, check who it is. So far, the catastrophic predictions are consistently coming from people who have been professionally and personally committed to shutting down nuclear weapons and nuclear power for decades.
So - who knows. There are conflicting reports circulating - some predicting major catastrophe and some predicting that this will be a non-event. Everyone seems to have an agenda - whether its "pro-nuclear" or "anti-nuclear". I guess we'll have to wait and see what happens.
Meanwhile, the situation in the post-earthquake Japan continues to worsen:
Panic buying leaves shelves empty following earthquake
Panic buying of food and other basic supplies since Friday’s earthquake have left supermarket and convenience store shelves empty throughout the capital. Traffic congestion has meant that distribution of stock has proved difficult. With electricity shortages resulting in rolling power outages across affected areas, it has become clear that the effects of the earthquake are becoming long-term ones.
In Tokyo’s Minato Ward supermarkets are completely sold out of bottled water, green tea, processed food, bread, bakery items, instant meals and other goods. One shop assistant said, “There are a lot of people stockpiling water. It looks like are customers are going to be inconvenienced for a while.”
As stated before, and at the risk of stating the obvious, we need to be in prayer for the people of Japan, and all those who are participating in their aid and assistance.
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