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Negligent design doomed the Fukushima Daiichi Nuclear Power Plant to failure. The President of its operator, Tokyo Electric, is stepping down, dishonored.  (Source: AP Photo)

Tokyo Electric's President met with the Governor of Fukushima this week to apologize. The Governor demanded the Fukuhima I plant be completely retired. He also demanded TEPCO to fully compensate farmers, fishers, manufacturers, and the tourism industry for lost business.  (Source: Mainichi)

"A Fukushima" is entering the pop culture vernacular as a term for something that's a mess -- particularly due to a history of negligence. For example, Lindsey Lohan was referred to as a "medium Fukushima", while Saab's recent plant shuttering was a "small Fukushima".  (Source: TMZ)
TEPCO President vows to step down for endangering public by failing to waterproof plant's backup generators

Yuhei Sato, the governor of Japan's tsunami-stricken Fukushima province, vowed this week that the damaged Fukushima Daiichi (Fukushima I) nuclear power plant would not be allowed to restart.  Meanwhile the Tokyo Electric Power Company (TEPCO) (9501) is facing serious questions and financial liability, for its role in only the second major nuclear power mishap in history.

I. How Did We Get Here?

Few energy sources have as high a power density as nuclear plants.  Yet the public is very fearful of new, safer nuclear designs, while the U.S., Japan, and other nations have fought to slow new reactor deployments.  The net result is that legacy plants' lifespans are being extended well past their original timelines.

To make matters worse, utilities operating Japan's 30+ year old Fukushima nuclear plants failed to water-proof backup generators despite the plants being in a region prone to tsunami and monsoon flooding.  

The combination of the lengthened deployment plus negligent engineering and/or management decisions proved a dangerous one.

While most modern nuclear designs are incapable of melting down, the Fukushima plants were ancient designs very capable of doing so.  They escaped the earthquake itself unscathed, but were unable to cool the rods after the reactions were stopped.  

As a result, some of the reactor cores are suspected of at least partially having melted, releasing radioactive caesium and iodine into the local air, soil, and water.

II. Harsh Words for TEPCO

Fukushima's governor is not responding kindly to TEPCO's blatant negligence.  He held a 15-minute meeting with TEPCO president Masataka Shimizu, stating, "A resumption of plant operations must be impossible."

Mr. Shimizu profusely apologized for his company mistakes and promised to resign from his position when the time was appropriate.  It is traditional in Japanese culture to abdicate a leadership position or engage in even more extreme gestures of repentance, when you are dishonored.

The TEPCO chief had tried to meet with Gov. Sato twice before, but was rebuffed.  At the time the governor commented, "The anger and fear of people in this prefecture have reached the limit."

Gov. Sato accepted the apologize, conditionally, demanding that Mr. Shimizu fully compensate local farmers and fishermen whose crops and catches were forced to be destroyed due to radioactivity contamination.

He also demanded that TEPCO repay manufacturers who lost money due to the evacuation of the 20-mile radius surrounding the plant and to tourism businesses who have seen a massive drop in foreign visitors since the accident hit international news outlets.

The Governor said that while TEPCO's performance was disappointing, its employees performed admirably in trying to shut down the damaged plant and prevent further radiation release.  He called TEPCO's workers the "rising stars for Fukushima" and complained that Mr. Shimizu needed to provide them with better medical coverage.

III. The Fate of the Fukushima Plants

Fukushima I's reactor 1 had been operation since 1970.  Prior to the disaster it was scheduled to be decommissioned in April.  Reactors 2-4, built in the 1970s were expected to soon follow.  

Following the disaster, TEPCO Chairman Tsunehisa Katsumata had told reporters that four of the six reactors had been decommissioned.  But he failed to make clear what the fate of the newer reactors 5 and 6 would be.  It now appears those will undergo a mandatory shuttering, as well.

The decision by the government to force the complete closure of the Fukushima I power plant likely kills plans to build two advanced boiling water reactors on-site.  Ironically, these ABWRs would have been meltdown-proof, due to their design, which includes passive emergency cooling.

While the fate of the damaged northern plant appears to be sealed, the fate of the southern Fukushima II power plant, which also sustained damage, is unclear.  The second plant featured more modern second-generation designs, built in the 1980s.  It is thought that containment at these plants largely held due to the design improvements, despite a similar loss of backup power.

It is possible that Fukushima II will resume operations.  

Hopefully, the plans for the meltdown-proof ABWR reactors will be shifted to the second site, which currently only houses four reactors.  There are no guarantees, though, as the people of Japan, like many in the U.S. have largely entered in an under-informed state of nuclear panic and hysteria. 

Some at least seem to be getting the underlying message of several small negligence-induced problems leading to bigger issues.  Jalopnik recently quoted Saab's Chairman Victor Muller referring to his plant shutdown as a "small Fukushima" -- to which a commenter quipped, "Coincidentally for those very same reasons, Michael Lohan calls his daughter a 'medium Fukushima'."



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RE: Can't melt down?
By Master Kenobi (blog) on 4/22/2011 4:27:38 PM , Rating: 2
You will find that they way they operate, if the power were removed and they were not being fed anymore, the reactions would stop and the reactor would not melt down. It is quite accurate to state modern designs can not melt down.


RE: Can't melt down?
By DanNeely on 4/22/2011 6:55:25 PM , Rating: 2
The reactions did stop at Fukishima. The problem is that residual decay keeps the fuel extremely hot for months after its shut down. Newer models with passive cooling have a gravity fed water tank with enough water to keep things cool for several days. IT wouldn't have lasted the entire time that Fukishima Daiichi was unpowered, although the external tank may have been easier to refill via firehoses. In earthquake zones however a giant tank of water up on poles isn't the most survivable of constructs.

To get something impossible to melt down you need to go beyond the current 3rd generation reactors to a pebble bed, or some of the other 4th gen designs on the drawing board. None of these are currently in operation.


RE: Can't melt down?
By Baenwort on 4/23/2011 2:33:28 PM , Rating: 2
Actually China has a 10MW Pebble Bed Reactor(a Gen 4 Design) that has been running at full power generating electricity since 2003(Initial Criticality in 2000) and broke ground on a 210MW version this month.

For the 210MW version:
http://www.nytimes.com/2011/03/25/business/energy-...

For the 10MW Version:
http://www.tsinghua.edu.cn/publish/ineten/5696/ind...

The biggest trouble with the Chinese designs is that, instead of helping with the development of Brayton Cycle He turbines that has been the hold up with western deployment, they are going to use steam turbines which introduces the possibility of water entry into the reactor core. The addition of water to a PBR core will cause many of the design features that make it impossible to cause a melt down to be no longer valid.


RE: Can't melt down?
By Solandri on 4/23/2011 3:31:13 PM , Rating: 2
quote:
In earthquake zones however a giant tank of water up on poles isn't the most survivable of constructs.

Actually, it'd be more survivable than smaller buildings. A water tank on poles would be a spring-mass-damper system with a huge mass. That would give it a very low resonance frequency, and thus it wouldn't be excitable by an earthquake. Just give the legs enough flexibility to absorb the shaking, and it should survive just fine. The water tank will basically remain stationary from its inertia, while the legs wobble around underneath it. (Not that I'd recommend that design in an earthquake zone. In California we just build the tank on top of a hill.)

The most damage-prone structures in an earthquake are those without lateral strength (brick walls - push it sideways a little and the whole thing collapses), and those whose resonance frequency comes closest to that of typical earthquakes. That frequency happens to match up with 3-story buildings. If you look at the Loma Prieta and Northridge quakes, the buildings which collapsed were all 3 stories. The only building I've seen collapsed away from the tsunami zone in the Japan quake was also 3 stories. Skyscrapers get through just fine because, like this hypothetical water tank, their resonance frequency is so much lower than the shaking.

In earthquake zones, all major structures including nuclear plants get tested with a shaker (basically a huge turntable with offset weights which you can spin at different frequencies) to measure their frequency response to help predict how they'd react in an earthquake. Any water tower or tank whose resonance would be vulnerable to an earthquake would automatically be rejected and redesigned. Non-resonance strength design is a simple matter of building the structure to withstand the maximum accelerations you expect it to experience.


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