sanjo
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Posts posted by sanjo
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Rather cheekily, I will post a new one soon.
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And another special tomorrow night....
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They have evidence, but it's a secwet!
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What is FUBAR?
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Is it Gokase Highland?
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Can you put them in a spoiler for me onehunga?
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Yes, it was very hot and humid in Niigata today.
Not quite yet into autumn then!
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Yes, Canada. And Switzerland too.
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Why the UK?
And not France, Germany, etc etc........
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Only 6 weeks or so away, that will soon come!
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Glad K's pulled through.
Must have been a pisser hearing that when he told you!
Can't be that long for your house now.
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Another few weeks and we should be in that bloody great few months of autumn period with all the things to enjoy and look forward to.
I'm feeling positive today.
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Metabo Oyaji, what's your Fukushima (or elsewhere) plans for the coming season?
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Hasn't the exclusion zone always been 20km?
Outside of that, I am not sure.
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They just have great tech, Chriselle. Maybe Apple.
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Scientists at Japan’s Fukushima nuclear power plant are preparing for their toughest clean-up operation yet – two and a half years after three of the plant’s reactors suffered a meltdown in Japan’s worst-ever nuclear power disaster.
The operation, to remove 400 tons of highly irradiated spent fuel beneath the plant’s damaged Reactor No. 4, could set off a catastrophe greater than any we have ever seen, independent experts warn. An operation of this scale, says plant operator Tokyo Electric Power Company, has never been attempted before, and is wrought with danger.
An uncontrolled leak of nuclear fuel could cause more radiation than the March 2011 disaster or the 1986 Chernobyl catastrophe, say consultants Mycle Schneider and Antony Froggatt. “Full release from the Unit-4 spent fuel pool, without any containment or control, could cause by far the most serious radiological disaster to date,” the scientists say in their World Nuclear Industry Status Report 2013.
The operation has been tried before – but only with the aid of computers. This time it will be a painstaking manual process.
Here’s what needs to be done: more than 1,300 used fuel rod assemblies, packing radiation 14,000 times the equivalent of the Hiroshima nuclear bomb, need to carefully be removed from their cooling pool.
Arnie Gunderson, a veteran US nuclear engineer and director of Fairewinds Energy Education, told Reuters that “they are going to have difficulty in removing a significant number of the rods,” especially given their close proximity to each other, which risks breakage and the release of radiation.
Gundersen told Reuters of an incredibly dangerous “criticality” that would result if a chain reaction takes place at any point, if the rods break or even so much as collide with each other in the wrong way. The resulting radiation is too great for the cooling pool to absorb – it simply has not been designed to do so.
“The problem with a fuel pool criticality is that you can’t stop it. There are no control rods to control it,”Gundsersen said. “The spent fuel pool cooling system is designed only to remove decay heat, not heat from an ongoing nuclear reaction.”
The base of the pool where the fuel assemblies are situated is 18 meters above the ground. The pool itself is 10 by 12 meters, and the rods are seven meters under the surface of the water. One problem with that pool is it has been exposed to air in the 2011 catastrophe, when its roof was blown off by the explosion.
The operation is urgent – because even a minor earthquake could trigger an uncontrolled fuel leak.
The removal process is due to begin in November, with TEPCO predicting it will take approximately a year. Although TEPCO is confident the operation will be a success, some experts are more skeptical. TEPCO is currently failing to contain radioactive water seepage in another part of the facility.
Two empty fuel rods were removed as part of a test operation some time ago, but “to jump to the conclusion that it is going to work just fine for the rest of them is quite a leap of logic,” Reuters quoted Gundersen, of Fairewinds Energy Education as saying.
A giant steel frame currently towers over Unit 4, soon to be tasked with the extraction of the fuel assemblies. Each fuel rod weighs at around 300 kilograms and is 4.5 meters long. They also contain plutonium, one of the most radioactive substances known to man. The radiation builds up during the later stages of a core’s operation.
Toshio Kimura, a former TEPCO technician, told Reuters that the operation would normally be assisted by computers, but that luxury is gone. “Previously it was a computer-controlled process that memorized the exact locations of the rods down to the millimeter and now they don’t have that. It has to be done manually so there is a high risk that they will drop and break one of the fuel rods,” he said.
He is also expecting many issues for TEPCO ahead, as the process is estimated to take years. The scientists’ task is not made easier by the fact that the building is also prone to corrosion from salt water.
Removing the fuel rods is just one part of the cleanup operation, itself expected to take around four decades – according to the IAEA – during which any number of other problems could arise.
The fuel rod scare comes as TEPCO is currently failing to contain radioactive water seepage in another part of the facility – itself a growing issue with no concrete solution, apart from building a special underground wall. But with water quantity building up at an alarming rate, the most likely version of events is that the radioactive water will simply have to be released into the Pacific at some point. According to TEPCO, there are still “no perfect solutions.”
“If you build a wall, of course the water is going to accumulate there. And there is no other way for the water to go but up or sideways and eventually lead to the ocean,” Masashi Goto, a nuclear engineer who has worked at several TEPCO plants, told Reuters. “So now, the question is how long do we have?”
This situation is not made easier by the fact that Japan is a seismically active island. Earthquakes keep striking at random, and even a small tremor could set in motion a catastrophic chain of events.
Catastrophic is never a good word!
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I would agree there
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You're just comparing it with the army employed by Mt Granview!
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I always liked the green mile.
Finding Nemo is bloody great.
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Mad storms here too and a very eearily yellow.orange color to the evening before it got dark just now.
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Yeah saw some of the mad rain up there. Had a fair bit ourselves in the last week or so.
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Kagura: 39
Maiko Snow Resort: 17 (+)
Muikamachi Hakkaisan: 6
Naeba: 6 (-)
Fukushima Daiichi latest - hows the clear up going?
in General off-topic discussions
Posted
And here's this mornings new news
東京電力は８月３１日深夜、福島第一原子力発電所の原子炉建屋の山側にある井戸から、放射性物質のトリチウムを地下水１リットルあたり最大９００ベクレル（法定許容限度は同６万ベクレル）検出したと発表した。
昨年１２月～今年３月の掘削時に比べて２～１５倍の濃度に上昇していた。東電は、貯蔵タンクから漏れた汚染水３００トンが地中に拡散した可能性があるとみて調べている。
同原発では大量の地下水が建屋に流入し、汚染水を増加させている。抑制策として、地下水を井戸でくみ上げ、海へ放出する計画があるが、井戸の汚染で影響が懸念される。政府の汚染水処理対策委員会の大西有三委員長（京都大名誉教授）は「地下水の流れを正確に把握し、原因を調べねばならない」と話している。
Pollution concentration rise in well water around the plant