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Thread: 9.0 Earthquake Strikes Japan

  1. #76

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    http://www.guardian.co.uk/world/2011...uclear-reactor
    Japan may have lost race to save nuclear reactor

    Fukushima meltdown fears rise after radioactive core melts through vessel – but 'no danger of Chernobyl-style catastrophe'

    Highly radioactive water is now being detected outside the containment area at Fukushima, experts have warned. Photograph: Tepco/AFP/Getty Images
    The radioactive core in a reactor at the crippled Fukushima nuclear power plant appears to have melted through the bottom of its containment vessel and on to a concrete floor, experts say, raising fears of a major release of radiation at the site.
    The warning follows an analysis by a leading US expert of radiation levels at the plant. Readings from reactor two at the site have been made public by the Japanese authorities and Tepco, the utility that operates it.
    Richard Lahey, who was head of safety research for boiling-water reactors at General Electric when the company installed the units at Fukushima, told the Guardian workers at the site appeared to have "lost the race" to save the reactor, but said there was no danger of a Chernobyl-style catastrophe.
    Workers have been pumping water into three reactors at the stricken plant in a desperate bid to keep the fuel rods from melting down, but the fuel is at least partially exposed in all the reactors.
    At least part of the molten core, which includes melted fuel rods and zirconium alloy cladding, seemed to have sunk through the steel "lower head" of the pressure vessel around reactor two, Lahey said.
    "The indications we have, from the reactor to radiation readings and the materials they are seeing, suggest that the core has melted through the bottom of the pressure vessel in unit two, and at least some of it is down on the floor of the drywell," Lahey said. "I hope I am wrong, but that is certainly what the evidence is pointing towards."
    The major concern when molten fuel breaches a containment vessel is that it reacts with the concrete floor of the drywell underneath, releasing radioactive gases into the surrounding area. At Fukushima, the drywell has been flooded with seawater, which will cool any molten fuel that escapes from the reactor and reduce the amount of radioactive gas released.
    Lahey said: "It won't come out as one big glob; it'll come out like lava, and that is good because it's easier to cool."
    The drywell is surrounded by a secondary steel-and-concrete structure designed to keep radioactive material from escaping into the environment. But an earlier hydrogen explosion at the reactor may have damaged this.
    "The reason we are concerned is that they are detecting water outside the containment area that is highly radioactive and it can only have come from the reactor core," Lahey added. "It's not going to be anything like Chernobyl, where it went up with a big fire and steam explosion, but it's not going to be good news for the environment."
    The radiation level at a pool of water in the turbine room of reactor two was measured recently at 1,000 millisieverts per hour. At that level, workers could remain in the area for just 15 minutes, under current exposure guidelines.
    A less serious core meltdown happened at the Three Mile Island nuclear plant in Pennsylvania in 1979. During that incident, engineers managed to cool the molten fuel before it penetrated the steel pressure vessel. The task is a race against time, because as the fuel melts it forms a blob that becomes increasingly difficult to cool.
    In the light of the Fukushima crisis, Lahey said all countries with nuclear power stations should have "Swat teams" of nuclear reactor safety experts on standby to give swift advice to the authorities in times of emergency, with international groups co-ordinated by the International Atomic Energy Authority.
    The warning came as the Japanese authorities were being urged to give clearer advice to the public about the safety of food and drinking water contaminated with radioactive substances from Fukushima.
    Robert Peter Gale, a US medical researcher who was brought in by Soviet authorities after the Chernobyl disaster, in 1986, has met Japanese cabinet ministers to discuss establishing an independent committee charged with taking radiation data from the site and translating it into clear public health advice.
    "What is fundamentally disturbing the public is reports of drinking water one day being above some limit, and then a day or two later it's suddenly safe to drink. People don't know if the first instance was alarmist or whether the second one was untrue," said Gale.
    "My recommendation is they should consider establishing a small commission to independently convert the data into comprehensible units of risk for the public so people know what they are dealing with and can take sensible decisions," he added.

    © Guardian News and Media Limited 2011

  2. #77

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    Quote Originally Posted by Ninjahedge View Post
    Our difference in definition seems to be hinged on the scope of the situation we are defining.
    I think the difference is more fundamental. I can get documentation to backup what I'm saying. You seem to be making wild speculations.

    Like:
    That place could be sealed up for the next 1000 years and it would effect the world, and even Japan, rather insignificantly.
    Source:http://www.reuters.com/article/2011/...72T3NM20110330
    Assuming no drastic worsening of leaks from the tsunami- and quake-damaged plant, there will be no long-term exclusion zone like that around Chernobyl in Ukraine, the site of the world's worst nuclear disaster in 1986.

    "The worst-case scenario in terms of people re-occupying the area is that people might be able to go back within months," said Steve Jones, an independent nuclear and environmental consultant.

    "There's likely to be an extended ban on food production within the affected sector -- of about 20 to 30 km out -- that might persist for some time. But there is then also the option of applying all sorts of remedial measures."

    Experts say the key to the future of the current exclusion zone will be levels of radioactive cesium 137, which has a half-life of 30 years. That means that its radioactivity drops by 50 percent every three decades.

  3. #78
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    Quote Originally Posted by BBMW View Post
    The radioactive core in a reactor at the crippled Fukushima nuclear power plant appears to have melted through the bottom of its containment vessel and on to a concrete floor, experts say, raising fears of a major release of radiation at the site.
    This is what the melted down core at chernobyl looks like today:





    It's basically sitting in the basement on a concrete slab. The same seems to be probable at Fukushima Daiichi. The main difference between the two disasters is that the core at Chernobyl had no containment unit and literally blew up into the sky. The parts that didn't get blown onto Prypiat and into the atmosphere melted down to the bottom. At Fukushima, it's all going to melt to the bottom. The key will be preventing that material from escaping over the next thousands of years, either through disintegration and air contamination, or water contamination & outflow

  4. #79
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    Quote Originally Posted by ZippyTheChimp View Post
    I think the difference is more fundamental. I can get documentation to backup what I'm saying. You seem to be making wild speculations.

    Like:

    Source:http://www.reuters.com/article/2011/...72T3NM20110330
    How big is Japan?


    How many people live there?

    "The worst-case scenario in terms of people re-occupying the area is that people might be able to go back within months,"
    How does this refute my statement saying that sealing this area off for 1000 years would not adversely effect Japan, or the world, as a whole?

    IOW, I am saying, unlike my quote, that i people did not come back anywhere near this place for 1000 years, how much would it effect Japan as a whole? How many miles are we talking about as unusable?



    Let me phrase my initial point differently.

    If there was no major breach of the core, the levels would be lower.

    The levels that are present NOW are not indicative of a full breach, but they are indicative of a breach.

    Things are bad, but I believe that they fear the possibility of much worse. That there is more material in there that could make night lighting unnecessary for the next 500 years.

  5. #80

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    Quote Originally Posted by Ninjahedge View Post
    How big is Japan?


    How many people live there?
    We could talk about how this effects Japan's economy, which has been stagnant for a long time; how it effects the nuclear power industry in one of the most seismically active countries on earth, a country that imports its fuel; how you don't measure human misery as a ratio to the entire population.

    But why bother? I believe your remarks to be silly, and will let it go at that.

  6. #81
    Chief Antagonist Ninjahedge's Avatar
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    Gee. Thanks.

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    http://www.nytimes.com/2011/03/31/wo...1japan.html?hp

    Dangerous Levels of Radioactive Isotope Found 25 Miles From Nuclear Plant

    WASHINGTON — A long-lasting radioactive element has been measured at levels that pose a long-term danger at one spot 25 miles from the crippled Fukushima Daiichi nuclear power plant, raising questions about whether Japan’s evacuation zone should be expanded and even whether the land might need to be abandoned.

    The isotope, cesium 137, was measured in one village by the International Atomic Energy Agency at a level exceeding the standard that the Soviet Union used as a gauge to recommend abandoning land surrounding the Chernobyl reactor, and at another location not precisely identified by the agency at more than double the Soviet standard.

    The measurements, reported Wednesday, would not be high enough to cause acute radiation illness, but far exceed standards for the general public designed to cut the risks of cancer.

    While the amount measured would not pose an immediate danger, the annual dose would be too high to allow people to keep living there, according to Edwin Lyman, a senior scientist at the Union of Concerned Scientists, an American organization that is often critical of nuclear safety rules. Cesium persists in the environment for centuries, losing half its strength every 30 years.

    The International Atomic Energy Agency stressed that levels of contamination varied considerably from place to place. Experts said the measurement might represent a “hot spot” and might not be representative of larger areas, though that remains to be seen.

  8. #83
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    The International Atomic Energy Agency stressed that levels of contamination varied considerably from place to place. Experts said the measurement might represent a “hot spot” and might not be representative of larger areas, though that remains to be seen.
    They need to map this stuff more accurately. Spot readings will not give an accurate picture of not only how much radiation is where, but of possible transmission routes and media.....

  9. #84

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    Almost lost in the power plant crisis is the earthquake-tsunami devastation.

    30 Photos of Ships Swept Ashore

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    amazing








  11. #86

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    Entomb? Cement pumps flown in to nuke plant

    Same company that helped seal in Chernobyl is sending equipment



    msnbc.com staff and news service reports
    updated 57 minutes ago 2011-04-01T02:37:07

    TOKYO — Some of the world's largest cement pumps were en route to Japan's stricken nuclear plant on Thursday, initially to help douse areas with water but eventually for cement work — including the possibility of entombing the site as was done in Chernobyl.
    Operated via remote control, one of the truck-mounted pumps was already at the Fukushima Dai-ichi site and being used to spray water. Four more will be flown in from Germany and the United States, according to the German-manufacturer Putzmeister. The biggest of the five has an arm that extends well over 200 feet.
    "Initially, they will probably pump water," Putzmeister stated. "Later they will be used for any necessary concreting work."
    A construction company in Augusta, Ga., was among those redirecting the pumps to Japan. Its owner said he believes building a concrete sarcophagus will follow.
    "Our understanding is they are preparing to go to next phase and it will require a lot of concrete," Jerry Ashmore told the Augusta Chronicle
    He did not expect the pump to return. "It will be too hot to come back," Ashmore said.
    A cargo plane is expected to fly the truck and pump from Atlanta next week at a cost of $1.4 million.

    Putzmeister concrete pumps were among those used to seal in the Chernobyl reactor after it exploded in Ukraine in 1986, and sightings of the first truck at the Dai-ichi complex last week led to media speculation that Japan was planning to do the same in Fukushima.

    Read the rest at:
    http://www.msnbc.msn.com/id/42359020...ws-asiapacific

  12. #87

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    They refer to this as the "elephant's foot" Click image for larger version. 

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    The thing that is most amazing, for me, about the ships is that you get a feeling for the sheer size of the wave that came though. It was not just a crash and tumble, it literally picked up and CARRIED these boats with 20 foot drafts UP AND OVER the ground and plunked them down on shore in one piece.

    That is more than just a "wave" or even a "wall". Walls do not float cargo ships. That is a HUGE field of water......

  15. #90
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    The ocean actually changed its boundaries for a brief period.

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