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Negligent design doomed the Fukushima Daiichi Nuclear Power Plant to failure.  (Source: AP Photo)
Company is forced to examine whether quake may have damaged the plant buildings or generators, as well

Something happened at the Fukushima Daiichi that's only happened once before in the history of nuclear power -- a full meltdown occurred.  Only this time, unlike the previous incident at Chernobyl in Soviet Ukraine, a natural disaster was to blame.

I. TEPCO Gives Disaster Timeline

In the wake of the disaster Tokyo Electric Power Company (TEPCO) (9501), the operator of the damaged plant, is still working to clean up the contaminated water now that the rods have been cooled.  

And it's facing tough questions from the Japanese government, both at a provincial and national level.  The governor of Fukushima recently admonished the head of TEPCO and ordered that the Fukushima I (Daiichi) Power Plant be permanently shut down.

TEPCO has released a new report, trying to sate the Japanese government's demands.  The analysis provides a fascinating timeline of the events that are believed, based on evidence, to have occurred in the early hours of the disaster.

According to the timeline, within 5 hours of the quake, which occurred on March 11, the fuel rods were exposed and rapidly melting.  By the next morning, 16 hours later, the uranium rods in Reactor No. 1 had melted down and dropped to the bottom of the core's cylindrical steel containment vessel, which holds the nuclear fuel during reactions.

Reactors No. 2 and 3 also melted down, following a similar frame of events. 

As the Japanese pumped in water to cool the damaged reactor, it leaked out of the containment vessel, creating a large pool of radioactive water.  This water contains longer-lived isotopes like Caesium-137, which has a half-life of 30 years, approximately.

Authorities fear that the water could leak, contaminating ground and seawater.

II. Chance to Advert Meltdown May Have Been Lost Due to Inaction

On the morning after the quake TEPCO finally decided to vent steam from the reactors in an effort to reduce them from heating.  One thing the Japanese government is upset about is that TEPCO didn't vent them sooner.  It was instructed to vent them on March 11, but failed to act until the next morning.

Nuclear Safety Commission Chairman Haruki Madarame told Japan's Parliament, "We can certainly say that if the venting took place a little earlier, we could have prevented the situation from worsening."

Prime Minister Naoto Kan and Trade Minister Banri Kaieda also criticized TEPCO, stating that they had ordered the company to act, but that it did not immediately do so.  Stated Mr. Kaieda, "We had instructed them to go ahead with the vent and I think Tokyo Electric was trying to do this. Even though we asked them repeatedly to vent, it did not happen and so we decided to issue an order. All of us there, including the prime minister and myself had said it should be done as soon as possible."

It is thought if the steam was vented sooner the rods could have been cooled faster, preventing the full meltdown that occurred.

III. Did the Quake Damage the Plant?

TEPCO, under government orders, is now conducting a study examining the events immediately after the record-setting magnitude 9.0 quake that struck Japan.  The question being raised is whether the quake itself could have damaged the reactor building or backup generators.

It is widely believed that the plant escaped the quake intact, with all reactors properly terminating nuclear reactions.  It is thought that the subsequent tsunami flooding was what knocked out the backup generator, preventing the rods from being properly cooled down.

The possibility that the quake itself damaged the backup generators hasn't been ruled out, though.  Junichi Matsumoto, a spokesman for Tokyo Electric Power Co on nuclear issues, told reporters, "We want to review the data from the 40 to 50 minutes between the time of the earthquake and when the tsunami struck."

Japan's Kyodo news agency cited an unnamed source as claiming that the reactor building at Reactor No. 1 is though to have sustained structural damage from the quake.  This is troublesome as it raises the possibility that radioactive water may have leaked from the building after it seeped out of the containment vessel housed inside.

IV. Conclusions

The Fukushima nuclear disaster shows the dangers of using ancient reactor designs in flood-prone regions without proper precautions.  TEPCO likely skipped on flood proofing the backup generators for expense reasons, but in the end paid a far greater cost for their negligence.

The disgraced firm has been working hard to try to minimize the damage resulting from accident.  In that regard, it is perhaps handling the incident better than authorities did Chernobyl.

However, the familiar themes of outdated technology and gross negligence were central to both the Chernobyl and Fukushima stories.

The impact of the disaster remains to be seen, but one thing is for the sure -- the accident stands as a stirring cry to decommission older reactors and move to modern designs, and as damning condemnation on engineering negligence.



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Speculation, as always by Mick.
By SunTzu on 5/19/2011 11:08:10 AM , Rating: 2
This plant was built to spec. Of course the accident was preventable, every single accident in the world is preventable, its just a matter of cost. The fulfilled every security demand put forward by the Japanese authorities, who vastly miscalculated the risk of a major earthquake and tsunami. Did Tepco make mistakes? Certainly. Were they to blame for the Japanese authorities inability to properly inspect the plant? No.

You do not expect private companies to do everything as safe as possible, you expect them to do everything as cost efficient as possible. That's why you have federal regulations, and the Japanese suck.




RE: Speculation, as always by Mick.
By mmatis on 5/19/2011 11:45:03 AM , Rating: 4
Hind sight is 20/20. And you expect them to do everything as cost-efficient as they believe they can live with. If they had forseen a disaster such as occurred, the plant WOULD have been built far differently.

TEPCO is a power company, not an earthquake prediction company. They relied on the Japanese government's requirements, because the government had THEORETICALLY used qualified experts to develop those requirements. However, they also undoubtedly did some calculations on their own to verify the requirements seemed reasonable. TEPCO management knew they would be held responsible for a major failure even if they met all government requirements. And it is not cost efficient for a company to have to pay for what TEPCO now has to pay for. Not to mention the loss of face they have suffered, which is immeasurably worse in their culture...


RE: Speculation, as always by Mick.
By SunTzu on 5/19/2011 1:36:17 PM , Rating: 2
Exactly. They're not responsible for making accurate predictions of the odds of a 9.0 earthquake, they're responsible for building and running a plant according to government spec. They did that.


RE: Speculation, as always by Mick.
By 91TTZ on 5/19/2011 3:13:40 PM , Rating: 3
quote:
Exactly. They're not responsible for making accurate predictions of the odds of a 9.0 earthquake, they're responsible for building and running a plant according to government spec. They did that.


Actually, part of their responsibility was to make predictions of the odds of a powerful earthquake. They were responsible for finding out what intensity earthquake was likely to occur during the lifetime of the plan, and then they were responsible for making sure the plant could survive that earthquake.


RE: Speculation, as always by Mick.
By SunTzu on 5/21/2011 9:02:52 PM , Rating: 2
What you are describing *is* part of the government spec they were given.


By Lerianis on 5/24/2011 7:27:23 AM , Rating: 2
Hit the nail on the head, SunTzu. The fact is that the government told them that there was basically NO chance of a 9.0 earthquake, but a 8.0 earthquake was likely.

So, they built to the 8.0 earthquake standards.... unfortunately, the government numbers were wrong (though I give them a lot of leeway here, earthquakes are nearly impossible to predict).


By bh192012 on 5/19/2011 3:05:38 PM , Rating: 3
They were required to vent, then they waited while fuel rods began heating up and eventually melted.

What's to understand? There is no "maybe." Venting and pumping in water would have prevented a full meltdown. They even turned down fresh water we flew in. Then danced around dodging the fact that they'd have to saltwater their reactor and ruin it. Also, the hydrogen build up isn't some kind of unknown reaction that we just discovered, there was nothing done about that.

Where were the backup generators from other plants that were not damaged by the wave?

This was a multiple fail by management.


RE: Speculation, as always by Mick.
By Tuor on 5/19/2011 12:10:15 PM , Rating: 5
I agree with SunTzu that there's a lot of speculation here, among other things.

First, as others have said, an earlier venting of the reactor *may* have prevented a full meltdown, or it may only have delayed it for a while. All the reactors that were operating at the time ended up having some significant amount of meltdown.

Second, time will tell how much damage was caused by the quake as opposed to the tsunami. But it is undeniable that the flood caused by the tsunami is the main cause for the metldowns in reactors #1, #2, and #3.

But here is the part that really stood out to me:

'The Fukushima nuclear disaster shows the dangers of using ancient reactor designs in flood-prone regions without proper precautions. TEPCO likely skipped on flood proofing the backup generators for expense reasons, but in the end paid a far greater cost for their negligence.'

Really. Negligence? They would be negligent if they were *required* to fully waterproof things and failed to do so. They placed the generators on the highest point of land in the area. TEPCO *and* the government were apparently satisfied with the safety measures taken. So, I think "negligence" is far too strong a word to use here. Events showed that their precautions were ultimately insufficient, but I doubt anyone anticipated the sort of tsunami generated by that earthquake. In the future, this will be taken under consideration not just in Japan, but world-wide.

As far as "ancient reactor designs" goes, when these plants were built, the designs weren't ancient. Time moves and science progresses. Engineering knowledge grows and technology improves. The reactors were older models, and one was due to be shut down, but they were all still performing as designed. It's not like TEPCO can just swap out an old model for a new one, just like the Space Shuttle, they're stuck with using what they've got until it can no longer safely perform its function.


RE: Speculation, as always by Mick.
By JasonMick (blog) on 5/19/2011 1:59:55 PM , Rating: 4
quote:
As far as "ancient reactor designs" goes, when these plants were built, the designs weren't ancient. Time moves and science progresses. Engineering knowledge grows and technology improves. The reactors were older models, and one was due to be shut down, but they were all still performing as designed. It's not like TEPCO can just swap out an old model for a new one, just like the Space Shuttle, they're stuck with using what they've got until it can no longer safely perform its function.


But we're not in 1970 (when the first reactor was built). We're in 2011.

Sure it's not easy to build new reactors, but consider that new reactor designs literally can't melt down (they're passively cooled). Is there really any justification for not starting this transition in as timely a manner as possible?

Sure these kind of events may be rare, but they CAN HAPPEN with current regulations and older plant designs. And what happens is then the public/government behaves like a flock of sheep, panicking and canceling all plant construction.

Is it really worth it to milk a few more years of life out of these plants?

And remember the new reactors will produce MORE POWER... what's not to like?

quote:
Really. Negligence? They would be negligent if they were *required* to fully waterproof things and failed to do so. They placed the generators on the highest point of land in the area. TEPCO *and* the government were apparently satisfied with the safety measures taken. So, I think "negligence" is far too strong a word to use here.


I'm sorry but your goal as an engineer should be to make a design that works, not a design that narrowly meets government regulations.

Sure there's issues with the regulations, but at the end of the day the legal liability for this mess falls on TEPCO, as does the moral responsibility.

If Toyota designs a car that doesn't brake properly 0.1 percent of the time, perhaps that's within the Japanese gov't's regulatory standards (purely fictitious example), but that doesn't exempt them from legal or moral responsibility if a mess occurs (peoples' cars start crashing).

quote:
Events showed that their precautions were ultimately insufficient, but I doubt anyone anticipated the sort of tsunami generated by that earthquake. In the future, this will be taken under consideration not just in Japan, but world-wide.


What???? That's like people in Louisiana not expecting a flood.

Japan has regularly been hit by tsunamis THROUGHOUT recorded history. Why do you think there's tsunami signs, tsunami sirens, etc. all over Japan.

Not preparing backup generators -- a mission critical component -- to withstand tsunami flooding was pure stupidity and gross negligence.

Hindsight is 20/20, but so is observing the obvious. C'mon now.


RE: Speculation, as always by Mick.
By SunTzu on 5/19/2011 2:23:01 PM , Rating: 2
Really, are you saying there are any Gen4 truly passively cooled reactors currently in operation? Seeing as how you're recommending that as the solution. Both GE and Westinghouse, and many others, are working on a solution to passive cooling that actually works in practice. Noone has succeeded yet, and for good reasons.

How was this caused in any way by old plant designs? The vast majority of reactors currently under construction are still good old BWR or PWRs.

They did have precautions against flooding. The wave that came was far, far bigger then they ever expected. Thats not an issue with bad plant design, thats a whole different kind of failure. They could have been running an RBMK reactor and have it shut down flawlessly with the proper precautions.


RE: Speculation, as always by Mick.
By omnicronx on 5/19/2011 2:32:57 PM , Rating: 2
Even GenIII designs are inherently safer than GenII designs. (and are in the here and now)

While Gen4 designs are still theoretically and probably won't arrive until 2030, GenIII+ designs (safer and significant desgin improvements) will be coming online in the next few years. (The first actually being in Japan if I remember correctly)


RE: Speculation, as always by Mick.
By SunTzu on 5/19/2011 2:45:54 PM , Rating: 3
Yes, but gen3+ arent passively cooled, which seemed to be his point. Even an AP1000 will run out of water, and fairly fast too.


By omnicronx on 5/19/2011 2:52:38 PM , Rating: 2
Can't disagree there ;)

There won't be any passively cooled reactors for quite sometime, so I'm not too sure why people keep trying to point this out.

2030 is the estimate, and considering its essentially theoretical right now, we probably won't be seeing them any-time soon. (and that does not include the time it takes to scope out and build said reactors, which can take several years)


By JasonMick (blog) on 5/19/2011 3:39:18 PM , Rating: 1
quote:
Really, are you saying there are any Gen4 truly passively cooled reactors currently in operation?


There have been, in a test capacity... granted they had some issues, but if a nation set their mind to it and cleared the bureaucratic red tape it should be possible to move them to commercialization...

Some designs, like the pebble bed reactor and thorium-based designs are closer to commercial readiness:
http://en.wikipedia.org/wiki/Pebble_bed_reactor

quote:
They did have precautions against flooding. The wave that came was far, far bigger then they ever expected. Thats not an issue with bad plant design, thats a whole different kind of failure. They could have been running an RBMK reactor and have it shut down flawlessly with the proper precautions.


Their protections were minimal. The generators were not water-proofed, they were merely stuck on a local high spot (hill).

There's been much larger tsunamis IN RECENT HISTORY .... The 1896 Meiji-Sanriku earthquake had a 25 m tsunami. This one was only 10 m. It wasn't even the biggest tsunami to hit Japan in the modern era.

It'd be like designing a mission critical system without flood-proofing in Louisiana. Maybe it won't fail right away... but it's asking for trouble.

I don't see how you can justify failing to design backup generators that can survive a 10 m tsunami in a region that was hit by a 25 m tsunami just years before. That's just rolling the dice plain and simple.

They gambled, and ended up paying for their negligence.


RE: Speculation, as always by Mick.
By Tuor on 5/19/2011 2:38:53 PM , Rating: 2
quote:
Sure it's not easy to build new reactors, but consider that new reactor designs literally can't melt down (they're passively cooled). Is there really any justification for not starting this transition in as timely a manner as possible?


There are two: time and cost. There is considerable time involved in planning, getting the permissions and permits approved, doing the various studies required, and then the actual construction. Because of this, the gap between reactor designs and reactors built and producing power is always going to be considerable.

As for cost, it is my understanding that land is pretty expensive in Japan, and land that is properly situated for building a nuclear reactor even more so. If you're talking about swapping out reactors, then that means you'll have to take the old reactor off line and it will no longer be generating revenue. I brought up the Space Shuttle previously: NASA was obliged to use it as long as it felt it could safely do so, despite the fact that spacecraft design and material science has advanced a great deal since when they were designed. TEPCO is in the same position: you don't stop with the current setup until you've wrung everything you can out of it and it can no longer produce power within safe operating margins.

Ideally, yes, they would say, "Well, this reactor is getting long in the tooth and we'll have to replace it soon, better start moving on its replacement." But TEPCO has to go through lots of hoops to do that, as I mentioned previously.

As far as new reactors being capable of greater output. That's all well and good, but how long until the difference in output covers the cost of building a new reactor? If your point is that TEPCO will make more money by switching to a new reactor design, then *when* they see any profit from the replacement becomes relevant.

quote:
I'm sorry but your goal as an engineer should be to make a design that works, not a design that narrowly meets government regulations.


Qualify "design that works". Do you mean a design that allows the most efficient production of power possible? One with the greatest lifetime? One that is the most stable? It all depends on the goals in mind. Safety and stabilty are certainly major goals. Engineers look at *all* of the design criteria and prioritize them. The government is aware that companies like TEPCO cannot operate at a loss and so they put in regulations that ensure that companies don't lose sight of public safety concerns in their money-making goals. This is one of the main reasons government oversight exists. It is TEPCO's responsibility to operate according to regulations and it is the government's responsibility to make sure those regulations are effective.

If TEPCO was following regulations, then how can they be legally responsible? If they were *not* following regulations, then punishment will be forthcoming.

You liken this tsumani to floods in Luisiana, despite the fact that this is one of, if not the largest tsunami ever recorded in Japan. How much of a safety factor should they have used? They used enough for any forseeable situation, and the government approved it. If they'd gone short of that, then I could see reason to be upset (as well as numerous lawsuits), but so far as I am aware, they didn't do that.

I would love to see lots of modern designed reactors producing power, both in Japan and here where I live in the USA. I agree that bad press and ignorance is responsible for a lot of hand-wringing and confusion about nuclear power production. However, browbeating TEPCO over not having been prepared for a 9.0 earthquake producing a tsunami that created a wave of around 70 feet in height is, IMO, unfair.


RE: Speculation, as always by Mick.
By Belegost on 5/19/2011 2:50:05 PM , Rating: 2
quote:
I'm sorry but your goal as an engineer should be to make a design that works, not a design that narrowly meets government regulations.


You're obviously not an engineer in industry. The engineer's job is to make a design that works under the specified conditions, while meeting budget and deadlines. It is impossible to engineer a design that can account for all possible events. Perhaps we need to build things to survive the possible direct strike of a mile-wide meteor as well.

The best you can do is design for probable events. And it seems to me that based on probable disaster estimates generated 40 years ago (note that both engineering and risk assessment fields have advanced dramatically since then.) the engineers designed to meet the specifications. And to their credit the design worked for 40 years, and only failed under a rather low probability event, after the original lifetime estimates. Consider that Chernobyl was designed in the same generation, had this plant been built according to the same design we may have been looking at a situation in which much of mainland japan was rendered uninhabitable.

It may be argued that the plant should have been updated with newer risk assessments based on added tsunami and earthquake model data, however it seems like the plan was already in place to deactivate the plant entirely.

I think where we both agree is that the real failure is one of regulatory nonsense and a misinformed populace that has made it overly difficult to construct new plants in a timely fashion. I don't believe the company would have kept up maintenance and fuel costs on an inefficient aging plant if it had been easy enough to build a new one.


RE: Speculation, as always by Mick.
By JasonMick (blog) on 5/19/2011 3:27:25 PM , Rating: 1
quote:
You're obviously not an engineer in industry. The engineer's job is to make a design that works under the specified conditions, while meeting budget and deadlines. It is impossible to engineer a design that can account for all possible events. Perhaps we need to build things to survive the possible direct strike of a mile-wide meteor as well.


Are you really arguing that an engineer shouldn't design a system to protect against a predictable event?

Tsunamis have occurred regularly throughout Japan's history... this was not a surprise.

If you can't understand the difference between a low probability, but likely danger, versus a statistical impossibility (e.g. a meteor strike on the generator) YOU'RE not an engineer in the field... not a good one at least.

Additionally, there's a difference in standard engineering, versus mission critical design. Designing a part for the Space Shuttle is much more rigorous than designing your computer fan. If the computer fan breaks, big deal buy a new one. If the Space Shuttle breaks, your nation is embarassed, millions are lost, etc. Nuclear power is a mission critical design.

Thus it is reasonable to hold nuclear plant builders/operators to a much higher standard, as the cost of failure are also higher.

quote:
The best you can do is design for probable events. And it seems to me that based on probable disaster estimates generated 40 years ago (note that both engineering and risk assessment fields have advanced dramatically since then.) the engineers designed to meet the specifications.


Clearly those estimates were either badly cooked up or the TEPCO itself ignored them and cut corners and that went unnoticed. Either way, it's a moot point. TEPCO AND the Japanese gov't BOTH should have predicted and prepared for tsunami flooding. After all, it IS a predictable event in Japan.

quote:
I think where we both agree is that the real failure is one of regulatory nonsense and a misinformed populace that has made it overly difficult to construct new plants in a timely fashion. I don't believe the company would have kept up maintenance and fuel costs on an inefficient aging plant if it had been easy enough to build a new one.


We agree there, and at the end of the day that's the most important point, so that's good at least.

Normally the market dictates technology to advance towards safer and more efficient designs. Unfortunately nuclear technology met a huge roadblock of mass public ignorance and political posturing over the past few decades...


RE: Speculation, as always by Mick.
By croc on 5/19/2011 9:13:37 PM , Rating: 2
"If you can't understand the difference between a low probability, but likely danger, versus a statistical impossibility (e.g. a meteor strike on the generator) YOU'RE not an engineer in the field... not a good one at least."

Study statistics much? There is never, ever, a statistical impossibility. It might be highly improbable that a meteor will strike a nuclear power plant, but please find me a statistician that will say that this event is impossible. If everything (even your so-called mission critical stuff) had to be built to withstand anything that MIGHT happen, then it would never get designed, let alone built, as the probabilities for the 'anything' happening would be endless. Such as your meteor strike event.

So, in your statistical opinion, what was the probability of a tsunami of that size striking that area? Let me give you a hint... The Japanese have historical records going back many hundreds of years, and they have many excellent statisticians - they built a flood wall to a height deemed statistically valid for that area. Note, the wall was even increased in height due to concerns raised by new events that raised the statistical probabilities for a larger tsunami than originally thought.

So, to my mind at least, the reactors that were built and the protective measures undertaken were all deemed more than adequate by the engineers of the day, and were also given improved protections as new data were found. In hindsiight, would anyone ever again build a reactor on any coastal area? And if they did, would their backup generators be 'water-proofed'?

And in hindsight, would the US ever launch another shuttle in weather conditions such as the conditions at launch time of the Challenger? Or ignore foam insulation breaking loose during the launch of Columbia?


RE: Speculation, as always by Mick.
By 91TTZ on 5/19/2011 3:17:56 PM , Rating: 2
quote:
Sure it's not easy to build new reactors, but consider that new reactor designs literally can't melt down (they're passively cooled). Is there really any justification for not starting this transition in as timely a manner as possible?


If you would have asked them a week before the earthquake if those reactors would melt down due to an earthquake, they would have told you no, those scenarios have already been thought out and the current design is more than capable of handling it.

It was an unforeseen probability that caught them off guard. Even if you were to use the current "safer" designs, you might find that they, too, have glaring flaws that you couldn't see before. You just don't know until it happens.


RE: Speculation, as always by Mick.
By JasonMick (blog) on 5/19/2011 3:40:48 PM , Rating: 2
quote:
It was an unforeseen probability that caught them off guard. Even if you were to use the current "safer" designs, you might find that they, too, have glaring flaws that you couldn't see before. You just don't know until it happens.


Unforseen? It was a 10 m tsunami... a 25 m tsunami hit in 1896.

I fail to see how a natural disaster that regularly occurs in a region is "unforseen".


By Solandri on 5/19/2011 5:44:10 PM , Rating: 2
quote:
Unforseen? It was a 10 m tsunami... a 25 m tsunami hit in 1896.

Unusually large tsunamis like that one usually tend to be channeled and focused by the topography. The largest tsunami on record happened in Lituya Bay, Alaska. If you look at the map and where the landslide happened, it's pretty obvious that the coast directly across from the landslide would get hit with the biggest wave. Regions away from there saw much smaller wave heights.
http://geology.com/records/biggest-tsunami.shtml

All of this needs to be accounted for when predicting tsunami heights. You don't just take the biggest wave ever recorded and blindly apply it to the entire coast. Computers have allowed us to refine this process even more, which is why a stronger tsunami warning was issued for the U.S. coast from Oregon to north-central California than further North or South.

That said, the generators and their fuel tanks really should have been sealed to withstand submersion. There's an additional complication in that the generations will need to be operating while submerged (the quake triggers the reactor scram thus necessitating the generators kick in, and the tsunami hits after). But we've had diesel powered ships for decades whose engines continue to run just fine even if the ship is temporarily submerged by waves. So it's not like these problems are insurmountable.


RE: Speculation, as always by Mick.
By omnicronx on 5/19/2011 2:23:37 PM , Rating: 2
Yes Negligence.

When you put the money in to perform you own study of the chances of a tsunami wave larger than the break-wall (for this particular plant) and find that there is a 10% chance of happening in its lifetime without doing anything about it.. You are negligent.

The idea that following government regulation implies that you are free of all wrongdoing is laughable at best.
quote:
Based on that history, Sakai, a senior safety manager at Tokyo Electric, and his research team applied new science to a simple question: What was the chance that an earthquake-generated wave would hit Fukushima? More pressing, what were the odds that it would be larger than the roughly 6-metre (20 feet) wall of water the plant had been designed to handle? The tsunami that crashed through the Fukushima plant on March 11 was 14 meters high.

Sakai's team determined the Fukushima plant was dead certain to be hit by a tsunami of one or two meters in a 50-year period. They put the risk of a wave of 6 metres or more at around 10 percent over the same time span. In other words, Tokyo Electric scientists realised as early as 2007 that it was quite possible a giant wave would overwhelm the sea walls and other defences at Fukushima by surpassing engineering assumptions behind the plant's design that date back to the 1960s.


RE: Speculation, as always by Mick.
By Tuor on 5/19/2011 2:46:06 PM , Rating: 2
omnicronx,

In that case, then yes there seems to be evidence to support the accusation. If they determined that there was a significant chance (and I would call a 10% chance significant) of a wave topping the breakwall and swamping the emergency generators, then they should've modified their equipment to account for it.

I'll be interested in seeing how this is handled in the inevitable lawsuit(s) that will come from this disaster.


RE: Speculation, as always by Mick.
By JasonMick (blog) on 5/19/2011 3:44:29 PM , Rating: 2
quote:
In that case, then yes there seems to be evidence to support the accusation. If they determined that there was a significant chance (and I would call a 10% chance significant) of a wave topping the breakwall and swamping the emergency generators, then they should've modified their equipment to account for it.

I'll be interested in seeing how this is handled in the inevitable lawsuit(s) that will come from this disaster.


And regardless of the "study", a 25 m tsunami was experienced in 1896.

So designing a wall that *might* not be able to withstand a MUCH SMALLER 10 m tsunami (and didn't) is REALLY negligent...

Heck, you don't even need the study... just look at history... that tells you the design was negligent.

The only acceptable solution should have been to make the generators self-contained, water-proof units. It's not that hard to design a waterproof box. Sure cabling would have been a challenge, but simply make cables that can be quickly replaced and have backup cables on hand in case a disaster strikes and the power cable breaks.


RE: Speculation, as always by Mick.
By SunTzu on 5/21/2011 9:05:13 PM , Rating: 2
You have obviously not seen the pictures of the damage that was done to those generators. Trust me, we're not talking about a little bit of water splashing around, we're talking massive physical damage.


RE: Speculation, as always by Mick.
By Uncle on 5/19/2011 12:23:07 PM , Rating: 2
What are you saying. This talk of federal regulations goes against any Red neck American thinking. Tepco did what any American Corporation would have done. They have been given the right of self regulation. Government regulation!! that's Blasphemous. This is Capitalism and free enterprise at its glory. So enjoy the show as the Corporations show you how things are done without government involvement. Only difference is Americans are better at coverups. They have many years of experience starting from the President down.


RE: Speculation, as always by Mick.
By osserc on 5/20/2011 10:15:33 AM , Rating: 2
This is easily one of the dumbest replies I've ever read.

Us "Red Necks" aren't anarchists, we're just practical and we want an efficient government. Governments are necessary, as are police, fire, whatever. Reasonable regulations based on rigorous SCIENTIFIC study are fine, especially in circumstances, such as using nuclear power, where negligence can cause significant danger to the populace.

Do we need science-based regulations on nuclear power plants to ensure safety? Yes.

Do we need state laws making it illegal to buy or sell alcohol on Sunday? No.

Do we need a year's worth of red tape and bureaucratic nonsense requiring 7 different approvals so some guy can build a small grocery store on the corner near a neighborhood? No.

For serious now, stop being an idiot so we can have legitimate conversations.


By jamawass on 5/19/2011 4:18:13 PM , Rating: 2
In 2006 a nuclear safety report identified that Fukushima among other plants would not withstand a significant tsunami or powerful earthquake. Recommendations were made for waterproofing the backup generators but since these requirements were higher (and more expensive) than the national mandated requirements they were not complied with. TEPCO only has itself to blame, instead of spending millions now they're going to lose billions of dollars and poison us all in the process.


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