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Nerdchick
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this has probably been pointed out ... but boiling water reactors like the one in Japan have been are not widely used in the US. we prefer pressurized water

3/16/2011 5:37:18 PM

Nighthawk
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^Don't let something like that get in the way of smc attempting to troll everybody in here.

BTW latest is that TEPCO has apparently just about completed a new power line that will provide grid power to the plant so they can get the regular cooling systems back up and running. Wonder how much of them are still active though after seeing the destruction to the containment buildings?

3/16/2011 5:47:13 PM

mrfrog

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^^ *sigh* that's just plain not the case

Neither is the concept of "negligence". For all the history the Japanese nuclear industry has of this, how did it cause this accident? You can't answer that. The fact of the matter is that the earthquake probability distribution isn't a matter of nuclear engineering, and this unit failed because it wasn't designed for the disaster it faced. It is near impossible to argue otherwise.

This is a question of "how" safe the public wants to require the fleet to be. This is a civil question. It would, in fact, be nice to blame this all on the incompetence of the Japanese nuclear industry but that doesn't fit the facts.

Even top industry leaders have publicly spoken that the measures TEPCO and the Japanese government agencies took are more or less what we would have done. The technology is old (which forms a valid point) and we operate the same generation of plants here and may operate them much much longer.

3/16/2011 5:56:30 PM

A Tanzarian
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Quote :
"boiling water reactors like the one in Japan have been are not widely used in the US"


There are 35 operating BWRs in the US (out of 104 commercial power plants).

Of the 35:

2 are GE-2/Mk I
6 are GE-3/Mk I (similar to Fukushima 1)
15 are GE-4/Mk I (similar to Fukushima 2, 3, 4, and 5)
4 are GE-4/Mk II
4 are GE-5/Mk II (similar to Fukushima 6)
4 are GE-6/Mk III

3/16/2011 7:57:25 PM

smc
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The Hindenburg crash was a natural disaster...of static electricity.



But you're right, I don't blame the engineers. I blame the bureaucrats and public that allowed/demanded airships filled with hydrogen to fly in the first place.

3/16/2011 7:58:44 PM

mrfrog

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Hydrogen remains a viable lifting gas. With proper engineering we could still ride in Hydrogen blimps.

3/16/2011 8:19:37 PM

TKE-Teg
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^this

Go away troll

3/16/2011 8:38:52 PM

The E Man
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can't wait for the fusion days when we look back and say "haha, remember the days we had old fashioned nuclear energy and had to worry about radiation and radioactive waste?, haha, we were so backwards"

3/16/2011 8:55:22 PM

aaronburro
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umm, fusion will still have radioactive waste

3/16/2011 9:17:42 PM

ladysman3621
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The earthquake didnt do shit to the plant even though the plant was only designed to withstand a magnitude 7. In other words, it ate an earthquake that was 100 times worse than what it was designed to handle and without issue. On the other hand, the plant was designed to withstand a 27ft tsunami...this one was 30ft. Its a pretty robust system, but this natural disaster was pretty fucked. Quit whining. Since when did a little radiation hurt anyone?

3/16/2011 11:55:57 PM

The E Man
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Quote :
"umm, fusion will still have radioactive waste"

Nope. You must be thinking about fusion bombs which use fission ignition. The fission ignition is what produces the radioactivity in hydrogen bombs.

Hydrogen fusion power, using a non-fission source of ignition (like focused lasers) would not produce radioactive waste.

Fusion itself only produces helium.

3/17/2011 2:03:48 AM

CarZin
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This is all a lot of aggrivation just to boil water

3/17/2011 9:34:57 AM

Nighthawk
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Maybe even aggravation?

3/17/2011 10:06:00 AM

CarZin
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Damn it. I suck without spellcheck.

3/17/2011 11:27:35 AM

mrfrog

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Quote :
"Hydrogen fusion power, using a non-fission source of ignition (like focused lasers) would not produce radioactive waste."


It still produces nuclear waste as byproducts - material activation and unintended reactions. Aneutronic fusion is vastly cleaner than the forms we're working on right now, and even that will have side reactions.

Some groups are working on radically more efficient plasma heating/banging/compressing machines that could do proton-Boron reactions specifically for this reason. The side reactions would likely be small enough that you could tell the nuclear regulators to go take a hike, then you're selling Mr. Fusion units. Only problem is that people don't believe them, similar to how they don't believe the scientific feasibility of the magical unicorn headbutt fusion approach. However, I don't discount the possibility of a group, just like this, finding the way to absurdly cheap and clean energy that would lead to a new kind of economy and unthinkable productivity such that I could have as many robot slaves as I wanted. I just don't count on it.
http://focusfusion.org/

This is different from fission because fission produces a soup of radioactive nuclei as a product (not a byproduct) of the reaction.

3/17/2011 11:40:09 AM

TerdFerguson
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Quote :
"Progress Energy Led U.S. Nuclear Near-Misses, Group Says
"




http://www.bloomberg.com/news/2011-03-17/progress-energy-led-u-s-nuclear-near-misses-group-says-1-.html



I know near-misses is a loaded word and that most of these situations were probably minor in the big scheme of things.

still

3/17/2011 2:19:01 PM

mrfrog

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Indeed, why is this concept of a "near-miss" so concerning? What is it that they nearly missed?

To me, I think it's clear that there's something more to the nuclear regulations and the nuclear panic than the simple existence of the possibility of a catastrophic event. I think the problem is that (in perception at least) the distribution of events from a nuclear plant do not follow a comfortable hierarchy.

Earthquakes themselves are a good example of something that science has shown follows a distribution of many low-severity and few high-severity occurrences, with a perfectly solid continuum in-between. It is my suspicion that this is a reason that the people won't get validly and publicly fearful about the possibility of a mega-explosion at Yellowstone.

If nuclear plants severely damaged their fuel on a regular basis, it seems to me like a near-miss would not be strongly concerning. The fear is related to the fact that fuel damage is historically such a good predictor of major radiation releases to the surrounding area. So much effort is expended on offering fail-safe operation that hints of problems imply a greater danger (in the public's mind) than if nuclear wasn't such a ominously safe industry.

3/17/2011 3:39:32 PM

S
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[Edited on March 17, 2011 at 3:56 PM. Reason : .]

3/17/2011 3:43:06 PM

TerdFerguson
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^^ I think it's fair to perceive "hints of problems" as a "greater danger" that could possibly occur. I don't think people should be hysterical about it, but I think it's fair for them to show concern.

did you read some of the things that were pointed out?

Quote :
"The NRC said today that it canceled a meeting to discuss the restart of the Crystal River plant following the discovery of a new gap in the concrete containment structure. The plant was shut down in 2009 for a planned refueling outage and during the work, the company found gaps in the structure.

. . . . . . .

The most serious U.S. reactor accident last year occurred when electrical fires at Progress Energy’s H.B. Robinson plant in South Carolina triggered an unplanned reactor shutdown, followed by an “incredibly long series of mistakes” by plant operators that “revisited nearly all the problems” that led to a partial meltdown at Pennsylvania’s Three Mile Island plant 31 years earlier, the report said.

"


Another one that I read about (can't find link) was a leaking roof that caused control equipment to short out. Some of the other "near misses" I'm sure where much more minor compared to these I listed. Still, some of these examples show a bit of carelessness.

Now when you consider that only 14 "near misses" were found last year over the thousands of hours that plants were operating and that the paper pointed to several examples where regulators or plant operators found problems and corrected them promptly , I'd say that is overall pretty good.

But when you consider that 5 of those 14 near misses, including some of the worst ones, were all by the same company. Well I think that is fair to be concerned about.

[Edited on March 17, 2011 at 4:45 PM. Reason : also the GOLO comments on the WRAL article on this are worth the read]

3/17/2011 4:39:09 PM

mrfrog

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Let's be clear - you have NO reason to be concerned about a "hit".

Fukushima I wasn't just a "hit", it was a "hit and smash through the wall". Although we may have had 14 near misses (the NRC event report gives you a constant stream of things to worry about), we didn't have any hits. But this logic of worrying about a near miss flatly doesn't match the nuclear plant design principles.

Nuclear plants are built so that if something goes wrong with A (the reactor) then B (containment and other systems) still continue to work. But every near miss isn't a near miss of systematically A&B, but either A or B.

So what is it? Are the principles of the engineering not working? Was it a good idea in theory but not in practice? Or is there really no reason to be worried about near-misses?

3/17/2011 4:52:45 PM

smc
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You guys need to stop trolling this thread by posting all these scary news articles.

Quote :
"I think the problem is that (in perception at least) the distribution of events from a nuclear plant do not follow a comfortable hierarchy."


Agreed. Things can go from 1:1000000 odds to massive deaths very quickly, mostly as a result of human error in monopolistic companies swamped by bureaucracy. We manage this risk in the airline industry or even in typical factories where any accident would be localized to a few hundred or thousand people. Nuclear energy is an entirely different ballgame, and to this fellow sporting a tin-foil hat, the perfect storm of big government danger.

3/17/2011 4:57:46 PM

ladysman3621
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Just look at how many deaths per year are related to coal power.

3/17/2011 5:17:03 PM

TerdFerguson
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Quote :
"So what is it? Are the principles of the engineering not working? Was it a good idea in theory but not in practice? Or is there really no reason to be worried about near-misses?
"


Statistically like ^^ said there is probably no reason to be worried about near-misses. I can easily concede that, I'm not losing any sleep over Progress's screw ups; I realize there are backups on top of backups and in the worst of these near misses the backups worked perfectly. But I think its fair for people to be concerned when a company's record is suspect, making the company seem careless, especially when you consider that small problems can propogate. The culture at Nuclear plants should be striving for perfection.



^agreed, not only do they spew hazardous shit all day long, Coal ash ponds probably wouldn't fair well in an earthquake at all.





[Edited on March 17, 2011 at 5:28 PM. Reason : arrers]

3/17/2011 5:26:06 PM

mrfrog

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Quote :
"But I think its fair for people to be concerned when a company's record is suspect, making the company seem careless"


Mathematically, this does exactly the job of hollowing out the middle of the event severity vs. probability function.

If we're talking about a suspect company in that they would falsify records (historically this is what's relevant, since TEPCO had exactly this scandal), then you're talking about observing fewer low-severity events, and mid-severity events being "reduced" in severity. That is, until the entire thing has the top blow off and all is revealed, in which case there is no longer any reporting bias. So yes, this contributes to that non-uniform consequence-frequency curve.

[Edited on March 17, 2011 at 9:56 PM. Reason : ]

3/17/2011 9:54:49 PM

Steven
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those near misses are stupid.

just because you have an accident and it happens to happen at a nuclear power plant and you call it a nuclear accident does not mean its horrible.

"electrical fire that caused an unplanned shutdown"

i have seen this happen on MANY occasions....shutdown is pretty damn safe, your only concern is DHR, which i do not know how civilian plants handle that....probably the same way we do.

how they got to "3 mile island", im not really sure.


"when in doubt, scram it out"
"when you dont know, make it into a casualty you do know"

3/17/2011 10:40:22 PM

skokiaan
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Quote :
"The earthquake didnt do shit to the plant even though the plant was only designed to withstand a magnitude 7. In other words, it ate an earthquake that was 100 times worse than what it was designed to handle and without issue. On the other hand, the plant was designed to withstand a 27ft tsunami...this one was 30ft. Its a pretty robust system, but this natural disaster was pretty fucked. Quit whining. Since when did a little radiation hurt anyone?
"

3/17/2011 11:20:27 PM

aaronburro
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Quote :
"Nope. You must be thinking about fusion bombs which use fission ignition. The fission ignition is what produces the radioactivity in hydrogen bombs.

Hydrogen fusion power, using a non-fission source of ignition (like focused lasers) would not produce radioactive waste.

Fusion itself only produces helium."

You couldn't be any more wrong if you tried.

Quote :
"This is different from fission because fission produces a soup of radioactive nuclei as a product (not a byproduct) of the reaction."

Not to mention that fission starts with a nice bit of radioactive stuff to begin with, lol.

3/19/2011 5:16:01 PM

mrfrog

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^ he could be more wrong. Some people could even be more wrong without even trying very hard. Some of us are absolutely fantastic at being wrong.

Nuclear reactors start with slightly radioactive stuff, but that needs a lot of qualifiers. Ordinary 5% enriched fuel is clean enough and quiet enough that you can eat off it. It's very harmless, BUT, if you compared it to purified normal Uranium oxide, or to most normal things (probably even bananas) it has elevated radiation levels.

Contrary to intuition, the fuel going into the reactor has lower radioactivity than much of the Uranium ore. The reason is because Uranium decays, and has a long radioactive chain that follows that built up over billions of years possibly. Natural U-235 fraction used to be 6% and now it's 0.75%, that's just a matter of half-lives. Natural Uranium ore rock is actually something you should avoid and it presents one of the greatest risks through the entire fuel cycle because it doesn't have engineered barriers and stuff like that.

MOX fuel is much more radioactive.

3/20/2011 10:38:47 AM

aaronburro
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man, I'd love to get into the MOX plant out here, lol. sux that I got laid off so soon into my masters. grrr.

3/20/2011 9:04:33 PM

TKE-Teg
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Interesting article...

Quote :
"Lawrence Solomon: Japan’s radioactive fallout could have silver lining

Low exposure to the Nagasaki atomic blast resulted in longer lifespans

The immense suffering that the Japanese are enduring in the aftermath of their earthquake and tsunami is now compounded by torment over radiation releases from the Fukushima nuclear plant.

While the torment is understandable, based on the reported amounts of radiation released, it is uncalled for. The evidence from Japan’s populace — inadvertent guinea pigs in the largest radiation experiment ever, in the aftermath of the atomic bombings of Hiroshima and Nagasaki in 1945 — indicates that fears over radiation can be overblown.

Those who survived the immediate atomic blasts but were near Ground Zero died at a high rate from excess exposure to radiation. The tens of thousands more distant from Ground Zero, and who received lower exposures to radiation, did not die in droves. To the contrary, and surprisingly, they outlived their counterparts in the general population who received no exposure to radiation from the blasts."


Quote :
"“Among about 100,000 A-bomb survivors registered at Nagasaki University School of Medicine, male subjects exposed to 31-40 cGy [centigrays] showed significantly lower mortality from non-cancerous diseases than age-matched unexposed males,” the researchers found. “And the death rate for exposed male and female was smaller than that for unexposed.” The 31-40 cGy is a measure of radiation absorption higher than the general population in the vicinity of the plants is likely to have received.

The real-life studies of Hiroshima and Nagasaki survivors indicate that radiation affects the human body much as arsenic, sodium and many other substances do — they are beneficial in small doses, but can be harmful in overdoses. Yet the conventional scientific wisdom rejects these studies, and a multitude of other real-life studies, in favour of what is known as the Linear No-Threshold Assumption. Under this assumption, all exposure to radiation, no matter how small, is harmful in direct proportion to the dose. It is called an assumption because there is no proof of its validity. In fact, the scientists who espouse it freely admit that no proof for their assumption can ever be had because the risk is too small to measure statistically. In the absence of proof, they say, the only safe course is to assume danger."


Quote :
"The only evidence that exists as to the health of humans who have been irradiated at low levels points to a benefit, not a harm. Difficult though it may be to overcome the fear of radiation that has been drubbed into us since childhood, there is no scientific proof whatsoever to view the radiation emitted from the Fukushima plant as dangerous to the Japanese population, and certainly no reason for the Japanese to view those living near the plant as damaged goods. In all likelihood, though, many will nevertheless be viewed as such. If so, that will be one more tragedy heaped among the others that the affected Japanese population will need to endure."


btw the author of this article is the exec director of an anti-nuclear organization.

http://opinion.financialpost.com/2011/03/21/lawrence-solomon-reactor-victims-will-benefit-studies-show/

[Edited on March 23, 2011 at 1:58 PM. Reason : btw i didn't post the entire article, just parts]

3/23/2011 1:56:55 PM

mrfrog

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I wish that I could say that radiation hormesis made intuitive sense to me. But it doesn't.

It is a little puzzle of nature that the amount of radiation around us is apparently orders of magnitude less than what it would need to be to cause harm. Does evolution over-engineer, or does it push every single thing to the limit in the name of competition? I tend to believe the latter.

So why? Why can background increase 100x without anything apparently going wrong? That seems a mystery to me.

But there's a difference between an elevated background, and a sudden shower of radiation. I've heard a man 90 years old give a talk and mention that one time he opened a box at the wrong place and wrong time and got 50 REM, and then he used that as evidence that our radiation phobia is baloney. I get that.

But why??? Did nature already solve the cancer problem to its own satisfaction? Maybe evolution designed through eras when background was so much higher.

I'm just rambling. But these are interesting questions. Either way we're still using the precautionary principle right now.

3/23/2011 2:12:55 PM

Shaggy
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yea my guess would be a combination of higher levels of radiation in the past + general hardiness against other negative outside forces. our bodies regenerate damaged or dead cells which helps protect against more than just radiation damage.

3/23/2011 2:27:41 PM

disco_stu
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I'm not sure how much that jives with existing physical and medical models. Your immune system doesn't build antibodies to deal with radiation damage. It's not like it's a virus. I'm sure one of our resident nuke specialists will chime in though.

3/23/2011 3:42:20 PM

LoneSnark
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Quote :
"But why??? Did nature already solve the cancer problem to its own satisfaction?"

Quite yes. Your body will get cancer several times in its lifetime, you just wont notice thanks to your immune system. Often, people that are genetically predisposed to cancer do not get cancer more often than the rest of us, it is just that the mechanisms their body uses to fight cancer do not work as well.

3/23/2011 3:55:35 PM

Shaggy
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i dont really mean in terms of immune system i mean we've evolved cells that get old and die as a regular part of their normal existance. If some cells are damaged by radiation they're going to get replaced over time anyways so its not a big deal.

3/23/2011 3:56:46 PM

disco_stu
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"Replacement" occurs via replication of cells. If a cell has damaged DNA and replicates, it will carry that damaged DNA (unless it's so damaged that it can't replicate, or not so damaged that it can't be repaired) to the copies.

This is why cancer is an asshole.

[Edited on March 23, 2011 at 4:15 PM. Reason : .]

3/23/2011 4:14:43 PM

ssjamind
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Quote :
"The only evidence that exists as to the health of humans who have been irradiated at low levels points to a benefit, not a harm"


there's a bit of "whatever doesn't kill you makes you stronger" going on at the cellular level.

3/23/2011 4:14:55 PM

disco_stu
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Here's PZ Myers commenting on Radiation Hormesis
http://scienceblogs.com/pharyngula/2011/03/will_radiation_hormesis_protec.php

Quote :
"However, the key thing to note about hormetic effects is that they only apply at low dosages. Low dosages tend to be where the damaging effects are weakest, anyway, and where the data are also the poorest. The US government recommendations for radiation exposure are based on a linear no threshold model in which there is no hormesis to reduced effects at low concentrations for a couple of reasons. One is methodological. The data we can get from high exposures to toxic agents tends to be much more robust and consistent, and we do see simple relationships like a ten-fold increase in dose produces a ten-fold increase in effect, whereas at low doses, where the effects are much weaker, variability adds so much noise to the measurements that it may be difficult to get a repeatable and consistent relationship. So the strategy is to determine the relationships at high doses and extrapolate backwards.

Then, of course, the major reason recommendations are made on the simple linear model is that it is the most conservative model. The data are weaker at the low end; there is more variability from individual to individual; the safest bet is always to recommend lower exposures than are known to be harmful."

3/23/2011 4:20:20 PM

mrfrog

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btw, i did not previously know that we now get about as much radiation from medical procedures as from background.

Combine that with space travel, and our great grandchildren may be living high radiation lives.

3/23/2011 7:46:14 PM

Steven
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we just had a guy fly in from japan and had 700 mrem on his shoes.

he also got internally monitored and had Cs-138 internally...sucks for him...

[Edited on March 24, 2011 at 1:09 AM. Reason : yea]

3/24/2011 1:09:05 AM

Wintermute
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Here on the west coast my colleagues and I have measured 131-I in rainwater from fallout using a Germanium detector. 131-I is a fission product with a half life of about 9 days so any identification of it means it only comes from a fissioning system. Very cool.

3/24/2011 2:00:41 AM

mrfrog

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You guys got a HPGe detector? Impressive.

3/24/2011 8:13:05 AM

smc
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^^Awesome! I can't wait until my rainwater has fallout in it. So exciting!

3/24/2011 11:13:06 AM

FAI756843
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I'm not sure if this has already been said but the main reason this is a problem was because the diesel generators were placed in an underground facility. Had they been stored above ground, which is pretty much the standard, there would be almost no problems.

Because these generators were placed underground the tsunami flooded them and were made useless. If they had been placed above ground, this wouldn't have been a problem.

3/24/2011 11:26:04 AM

mrfrog

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u sure it wasn't because the fuel tanks for those generators were above ground in a place the fuel could be washed away or made useless by the flood?

3/24/2011 11:38:01 AM

TKE-Teg
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^^^I hope you don't live in a brick house. All that radiation would probably make you piss yourself in fear.

3/24/2011 12:23:29 PM

LoneSnark
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Last night I saw a documentary which showed a 30 foot high tsunami wall built to protect a small Japanese town. Would it have been so hard to put the nuclear reactor and all its little bits behind that or one like it?

3/24/2011 1:36:27 PM

mrfrog

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^ not only did they think of EXACTLY that, they did better. 30 feet is about 9 meters. So they only expected to ever, in their life, to get hit by one half that size. But they still over-engineered it (i'm sure laughing all the way "gawd this is stupid to overbuild so much") to a value very close to what this one was. That town and its puny wall was laughable to the nuclear plants. But no one is laughing now.

Quote :
"Tokyo Electric Power Company says its nuclear power plants in Fukushima, built on grounds 10 to 13 meters above sea level, were hit by a 14-meter-high tsunami. The company had only expected a tsunami of 5.7 meters at the Daiichi plant and one of 5.2 meters at the Daini."


http://www.nextlevelofnews.com/2011/03/tepco-fukushima-was-hit-by-14-meters-high-tsunami-but-built-for-a-max-of-57.html

3/24/2011 1:47:11 PM

ssjamind
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http://www.youtube.com/watch?v=WbrjRKB586s

3/25/2011 1:18:58 PM

CarZin
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3/25/2011 1:44:49 PM

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