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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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tragedy of errors, failure of imagination
By chromal on 5/19/2011 10:18:19 AM , Rating: 5
I agree with this article's conclusion that, yes, we really need to replace Gen-II reactors with Gen-IV passive-shutdown capable reactors and put these plants built by our great-grandfathers and grandfathers' generation to rest.

The more that comes out about TEPCO's early moments crisis management, the more we see poor management decisions and a few technical mistakes, but the sequence of events that led to the meltdown more or less became inevitable the moment the tsunami flooded the plant's aux generators, electrical switch rooms (precluding external generator power distribution even if they had all the mobile generators they needed), and now we learn, even a lot of the battery backup capacity.

The mistakes may have hastened the meltdown, but once the station was consigned to an extended plant blackout, the recently-scrammed reactors were essentially destined to melt down.

RE: tragedy of errors, failure of imagination
By Mitch101 on 5/19/2011 10:55:29 AM , Rating: 2
Throw in TEPCO's history.

The only real reason I suspect they refused the worlds help when the disaster began is because they didnt want the world to know how many additional things they overlooked or neglected to upkeep. Sad Karma.

RE: tragedy of errors, failure of imagination
By Strunf on 5/20/2011 7:54:19 AM , Rating: 2
What would the world be able to do?... communication would be a major problem, there aren't that many Japanese speaking people that could go there and Japanese people in general don't speak English at all.
Cultural issues they have their away of doing things we have ours, this is the main reason they aren't the open to outside help.

By SunTzu on 5/21/2011 9:06:55 PM , Rating: 2
My department in Sweden regularly works at Fukushima. (and still have, after the accident). The people that you work with at the plant do speak english, even though they are kind of daft. (They like sending emails about stuff they really should know, time and time again)

By SunTzu on 5/19/2011 11:13:42 AM , Rating: 2
The plant did shutdown automatically. The problem was fuel cooling after the plant shut down. The gen 4 reactors are *far* from being ready for construction.

There are some very decent gen3+ designs out there, and imo they are the way forward. You cant wait until 2030 to start replacing reactors that are 30 years old like Fukushima. If the plant had been using say AP1000 reactors this wouldnt ever have led to a meltdown.

RE: tragedy of errors, failure of imagination
By MonkeyPaw on 5/19/2011 1:04:59 PM , Rating: 2
So I will admit that I don't know much about reactor management, but what makes the Japanese government any wiser about how to manage this incident as it's unfolding? We're talking hours after it happened, and they claim they advised venting. Obviously TEPCO felt otherwise. I wonder what the reasoning was, and what the effects of the forced ventilation were? Sounds like everyone is distancing themselves from this, just like the BP oil spill.

RE: tragedy of errors, failure of imagination
By Azethoth on 5/19/2011 2:24:01 PM , Rating: 1
Venting (releasing radioactive material) is not something a government lets a company do whenever it feels like it. Venting is bad m'kay. They likely need government permission to vent.

RE: tragedy of errors, failure of imagination
By bh192012 on 5/19/2011 3:09:48 PM , Rating: 2
Actually I understand it as, venting means you lose a bunch of water you have to replace. Having already turned down water we offered, they'd have to use salt water (ocean) and that would damage the reactor so they couldn't re-use the plant. So instead of venting and trashing their reactor safely, they decided to gamble and lost, irradiating the countryside, ocean, people etc.

By SunTzu on 5/21/2011 9:08:06 PM , Rating: 2
The plant wasnt using any kind of "special water", getting ahold of freshwater was hardly the issue. When you vent steam, there are *alot* of issues, and its never done lightly.

"Young lady, in this house we obey the laws of thermodynamics!" -- Homer Simpson

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