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1 Year after Fukushima: Could It Happen in the U.S.?

The views expressed are those of the author and are not necessarily those of Scientific American.

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Border of the Fukushima exclusion zone. Credit: GaijinSeb/Flickr/CC

Last year, on March 11, a deadly earthquake and tsunami rocked Japan, killing more than 15,000 people. To make matters worse, the natural disaster triggered a major crisis at the Fukushima Daiichi nuclear power station. The subsequent meltdown and radioactive release is the only event in history other than Chernobyl to rate as a “major accident” on an international scale of nuclear severity. Fukushima is not expected to cause as many deaths as Chernobyl, but contamination from the accident is widespread and will be long-lived. One year after the nuclear crisis began, an exclusion zone 20 kilometers in radius remains in place around the reactors.

Could a Fukushima-scale nuclear incident happen in the U.S.? “There’s been a lot of debate on this issue,” physicist Edwin Lyman of the Union of Concerned Scientists said last week at a meeting of the American Physical Society in Boston. “In our view, complacency is as prevalent here as it is in Japan.” (Lyman and a colleague recently released a report [pdf] on the U.S. response to the accident.) One major threat to a nuclear plant is a prolonged power outage, or station blackout, like the one at Fukushima, which deprived the reactors of their cooling systems.

U.S. nuclear plants, Lyman said, are not well prepared to handle severe, “beyond design basis” events, such as major natural disasters, multiple system failures or terrorist attacks. A report last year by the Nuclear Regulatory Commission (NRC), which itself has been criticized for being too lenient with the industry it is supposed to oversee, revealed that many U.S. nuclear plants were vulnerable to extreme emergencies. “Regulators don’t usually impose stringent requirements to deal with these accidents, because they assume that they’re so improbable,” Lyman said. Indeed, the NRC has called the Fukushima crisis “the result of a combination of highly unlikely natural disasters.” That specific combination of mega-earthquake and tsunami, the agency maintains, would be very improbable in the U.S.

As an example of insufficient preparedness, Lyman cited the 2011 NRC inspection of the Edwin I. Hatch Nuclear Plant in Georgia. The NRC noted that the Hatch facility had procedures in place for only a one-hour loss of external power. “It didn’t really look to me that those preparations were something you could count on in the event of a Fukushima-type event,” Lyman said of the Hatch evaluation. After an hour, the Hatch plant’s operators assumed that backup diesel generators would be up and running. But at Fukushima the same cataclysm that knocked out normal electrical power also killed the generators. “Hatch’s procedures do not provide specific guidance for a prolonged loss of normal or alternate AC power, which is outside of the plant design basis,” the NRC reported. In other words, if the plant lost power and was unable to fire up the generators, the operators would quickly be forced into improvisation.

The NRC only requires that plants such as Hatch cope with a loss of power for four hours. (The agency has recently proposed extending that requirement to eight hours.) But at Fukushima, the station blackout lasted not just hours but days. The outage cutoff the reactors’ cooling pumps and caused the catastrophic overheating of nuclear fuel.

Nuclear power plants do keep batteries on-site in the case of a station blackout, but those last only hours. And from there, the situation deteriorates quickly, according to U.S. simulations of how a stricken plant would deteriorate in a prolonged accident. “After batteries fail, you’re going to get core melt after only about eight or 10 additional hours,” Lyman said.

But at Fukushima, a backup cooling system in one of the reactors worked far longer than that. A reactor core isolation cooling (RCIC) system, which runs on steam but requires battery power to control its valves, lasted for three days of the station blackout. “How did RCIC operate for three days? This is still a mystery,” Lyman said. “There’s no explanation for this phenomenon.” And whereas a cooling system outlasting its expected functional lifetime would seem to be a good thing, Lyman used the example to illustrate how little we can predict about what will happen in a nuclear crisis. “I don’t have confidence in the ability of current computer models to simulate a severe accident,” he said.

About the Author: John Matson is an associate editor at Scientific American focusing on space, physics and mathematics. Follow on Twitter @jmtsn.

The views expressed are those of the author and are not necessarily those of Scientific American.

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  1. 1. nosscaj 5:24 pm 03/6/2012

    Surprised this article did not mention this story…

    Then again, not many people are.

    Link to this
  2. 2. sault 1:14 am 03/7/2012

    When one side accuses the NRC of actively trying to stifle the nuclear industry and the other side claims that they are FAR to lenient with them…I tend to believe the latter claim because of the long and sordid history of corporate money corrupting the regulators that oversee industry. From the rampant drug-fueled parties at the MMS to the revolving door between government and industry positions, there is just too much money and influence by these corporations and their lobbyists for proper regulation to happen. When ONE catastrauphic failure at ANY of these nuclear plants can make thousands of square km uninhabitable and worthless, we need to stand on the side of caution.

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  3. 3. Asteroid Miner 1:50 am 03/7/2012

    2. sault: You are completely wrong. Chernobyl put out as much radiation as a coal fired power plant does in 7 years and 5 months. See:

    If I lived at Fukushima, and my house had not been damaged by the tsunami, I would not evacuate.  The radiation from the reactor has not exceeded natural background radiation in many inhabited places on Earth.  

    book:  ”Power to Save the World; The Truth About Nuclear Energy” by Gwyneth Cravens, 2007   Gwyneth Cravens is a former anti-nuclear activist.

    Page 77:   Natural gas contains radon, a radioactive gas.

    Page 98:   There is a table of millirems per year from the
    background in a list of inhabited places.   
    Chernobyl:  490 millirem/year
    Guarapari, Brazil:  3700 millirem/year   [=3.7 rem]
    Tamil Nadu, India:  5300 millirem/year    [=5.3 rem]
    Ramsar, Iran:  8900 to 13200 millirem/year   [=8.9 to 13.2 rem]
    All are natural except for Chernobyl.

    In Denver, Colorado, the natural dose is over 1000 millirem/year.   Denver gets more than 2.56 times as much  radiation as Chernobyl!   But Denver has a low cancer rate.

    Calculate your annual radiation dose:

    The Average American gets 361 millirems/year.   Smokers add 280 millirems/year from lead210.   Radon accounts for 200 mrem/year.

    Coal contains:   URANIUM, …. Thorium, ….   There is so much of these elements in coal that cinders and coal smoke are actually valuable ores.   We should be able to get all the uranium and thorium we need to fuel nuclear power plants for centuries by using cinders and smoke as ore.

    Metals and Ceramics Division
    Oak Ridge National Laboratory
    Oak Ridge, TN
    “For example, J. F. Facer showed in a 1979 US Dept. of Energy (DOE) report that some US coal contains in excess of 103 parts per million of uranium10. Consequently, deposits of coal with this concentration release more than 200 tons of uranium per 1000 N We/year compared to approximately 8 tons/year using IAEA average value data.”
    You get 100 to 400 times as much radiation from coal as from nuclear, if they don’t use the 103 ppm coal.

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  4. 4. Dr. Strangelove 2:22 am 03/7/2012

    Fukushima’s backup diesel generators were located at the basement. The tsunami flooded the basement and disabled the diesel generators. The power outage lasted for weeks so they had cooling problem with the reactors. Could this happen in the US? Yes.

    But in terms of radiation risk of Fukushima, it is happening all the time in the US. The highest radiation dosage received by the emergency workers in Fukushima was 25 rem. Cancer patients undergoing chemotherapy routinely receive radiation dosage up to 8,000 rem. They don’t die of radiation. They die of cancer.

    The fear of radiation risk is far worse than the radiation risk.

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  5. 5. Jones the Robert 7:38 am 03/7/2012

    If the batteries were modular and of a limited number of types used by several other power stations, then spares could be transported by truck or helicopter from stations that were not currently affected by a crisis.

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  6. 6. alan6302 8:57 am 03/7/2012

    David Suzuki in Canada is trying to blame the Americans because they encouraged nuclear power. Take your meds David Suzuki . Just because the authorities allowed had their fingers crossed ,does not make them blameless. He is a racist.

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  7. 7. JamesDavis 9:53 am 03/7/2012

    Now, you know there is nothing that can happen in America that will cause our nuclear power plants to go into a meltdown. Most calamities that happens in America only knocks your power out for less than an hour, that’s why our most modern nuclear power plant that is in production right now only has power backup for an hour…a longer time is not needed. Those scientists are lying and trying to scare us, and nuclear radiation will not kill you; what kills you is what caused the plant to go into a meltdown, not the radiation. Radiation has not killed a single person in the world and the nuclear bombs we dropped on Japan… the radiation was harmless, why else would a country that was bombed with nuclear radiation build 54 nuclear radioactive power plants? If radiation would kill you, they would not had build all those nuclear power plants; they would’ve built those warmists clean energy power plants like hydro or geothermal. So just lay off bad mouthing those nuclear power plants; they are as harmless and as safe as a housefly.

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  8. 8. DaithiM 11:46 am 03/7/2012

    JamesDavis, you are making some decidedly very bold statements, and also some that just make absolutely no sense. I am guessing you have read some blogs or maybe listened to fox news and are now, like so many others an expert on nuclear physics.

    1) There has already been a nuclear meltdown in America (three mile island meltdown) so your claim that it is impossible for it to happen in the USA is just wrong. It has and quite likely could happen again, especially with ageing power stations.

    I think Dr. Strangloves comment explains how easily something as benign as some flooding could cause a meltdown. It does not take a major disaster for things to go wrong. Or in the case of three mile island the failure of a coolant valve.

    2) You claim radiation doesn’t kill people and that it is harmless, please expose yourself to some gamma radiation to try and prove your theory. I think the many people who did die in Japan from radiation poisoning from the nuclear bombs dropped on them would also argue with you about this if they were alive to do so.

    3) Why would Japan build nuclear power plants? Surely even a someone like you can figure that one out. A small country without the natural resources to produce power cheaply, there are not really many better options other then nuclear power that are feasible (despite what you might claim). I imagine the Japanese government relied on gullible, ignorant people like yourself in order to sell the idea of nuclear power. In the greed does win over a lot of people. America is no different.

    4) You also claim scientists are just trying to scare people. Maybe they are but that does not make them wrong. I am a Physicist and would advise anyone that you can never be too careful when dealing with radiation. I would also encourage the proliferation of nuclear power as one of the best means of producing power but that is no excuse for complacency or making outrageous claims that a serious nuclear disaster will never happen in America, or Europe.

    In short you do know what you are talking about. Try reading something scientifically reputable instead of listening to conjecture and gossip before forming an opinion.

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  9. 9. DaithiM 12:02 pm 03/7/2012

    Also just to point out something obvious that many of you seem to be missing: radiation exposure can cause cancer. So no you may not die immediately of radiation exposure or even a few months after it but yes it might cause you to get cancer. Hence why areas that have been exposed to radioactive material are evacuated for decades.

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  10. 10. LTony 2:53 pm 03/7/2012

    As carcinogens go, radiation is a fairly weak one. Many people have been exposed to doses above the regulatory limits without contracting cancer. It’s even less likely that a Fukushima style natural disaster would occur in the US; not impossible, but very unlikely.

    Two good solutions come to mind:
    1. Build new reactors. Passive safety systems (meaning those that need no electricity) have been incorporated into the newer designs so that power failures cause the units to shutdown safely, with much less risk than designs from the 60′s and 70′s.
    2. Reprocess all that spent fuel. Yucca mountain won’t be built. A permanent, long term disposal site is decades away. Spent fuel was a bigger problem at Fukushima than reactor cores. Reprocessing spent fuel would eliminate the biggest threat in the US today, and provide cheap fuel for all those new reactors.

    These aren’t technical problems, they’re political ones.

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  11. 11. JamesDavis 3:32 pm 03/7/2012

    “DaithiM”, I am very familiar with radiation and the dangers of it and the horrible damage nuclear reactors pose to society and how dirty they are. I was mimicking and mocking the republican party. It seems like every time this rag has an article about nuclear power plants or the use of coal, oil, or natural gas, the conservatives come on here and clamor about how safe and clean they are and how radiation can’t harm you or kill you. Every time an article comes on here about nuclear power plants, you know exactly what the conservatives are going to say and what names they are going to call people who roots for clean safe energy. The conservatives also have declared that all environment scientists are lying and produce bogus reports on their computers and have declared that electric cars will cause the grid to plunge us all into darkness, but nuclear power plants will “praise the Lord”, save us form the darkness and those polluting electric cars. I am a tree huger and animal lover and I am very proud of it, and there is nothing you can say about how safe nuclear power plants are and convince that you are telling me the truth. We do not need nuclear power plants and they all should be dissembled and replaced with safe clean power plants like hydro, geothermal, solar and wind.

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  12. 12. geojellyroll 4:24 pm 03/7/2012

    We can actually be lulled by the incident in Japan. As a geologist I can assure you that this event was ‘small potatoes’. It’s not if ‘this’ happened but what ‘potentially’ could happen.

    Solution. I don’t know. everything is a trade off of benefits and risks. Best not to get ingrained in a position and make rationhal decisions.

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  13. 13. Potomac Planning 1:05 pm 03/8/2012

    Chicken Little The Sky Is Not Falling…
    We need to build smaller scale nuclear plants to serve more limited areas. Reduce the size of the plant and the size of the service population and you reduce risks. There are current plans to develop smaller safer facilities. They will also be easier to safeguard for local, regional, and national security purposes. Big has not proven to be better or wiser. Hal Marchand, Ph.D.

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  14. 14. DaithiM 6:58 am 03/9/2012

    @ JamesDavis, Where in my comment did I give you the impression I was trying to convince you that nuclear power was safe? Try reading instead of jumping to conclusions.

    I don’t know if you are just “trolling” this page but if you intend a comment to be sarcastic I recommend you specify so at the end. Without tone it is impossible to tell. At the moment both your comments are contradictions and it seems you are just intent on disagreeing with everything.

    I would suggest if you are genuinely concerned about nuclear power your comments would have more efficacy if you tried at least to educate yourself a little to make some type of scientific argument “on this rag”. Proclaiming everyone as a liar just makes your point of view seem like it is coming from a crazy republican or conservative. (I cannot tell which you are actually trying to be?)

    I agree it would be great if there was more renewable energy. Implementing renewable energy for the current demands is an extremely large challenge. One that has yet to be solved, in addition most of the methods you suggest can be very damaging to the environment also, or require large power storage facilities. There is currently no perfect solution, nuclear power is just another imperfect option to solve a human problem. Hopefully all those lying scientist will think of something.

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  15. 15. jctyler 11:47 am 08/14/2012

    saying that nuclear radiation is not killing anyone is the same as saying that smoking is not killing anyone.

    it’s the side effects, you twits.

    and they get worse with age.

    and can it happen in the US? If I look at the state of your electrical grid, the level of your cars, the quality of your nuclear powerplant safety or what you call state-of-the-art technology and then compare that to the European grid, European cars, European nuke safety standards and what Europeans consider state-of-the-art, can it happen in the US? Japanese standards are already better than US. They only made the same mistake the US make, hoping/dreaming/fantasizing that no earthquake would ever strike in their life time. Now look at where half of the US nuke plants are built… You bet it can happen in the US and I bet it will.

    Let’s meet again here in five years, see who still has a face to laugh it off.

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