Cleaner robot pulled from Fukushima reactor due to radiation

Cleaner robot pulled from Fukushima reactor due to radiation
In this image released by Tokyo Electric Power Co. (TEPCO), a remote-controlled "cleaning" robot, bottom, enters the reactor containment chamber of Unit 2 for inspection and cleaning a passage for another robot as melted materials are seen at Fukushima Dai-ichi nuclear power plant in Okuma town, Fukushima prefecture, northeastern Japan, Thursday, Feb. 9, 2017. The "cleaning" robot that entered one of three tsunami-wrecked Fukushima reactor containment chambers was withdrawn before completing its mission due to glitches most likely caused by high radiation. (TEPCO via AP)

A remote-controlled cleaning robot sent into a damaged reactor at Japan's Fukushima nuclear plant had to be removed Thursday before it completed its work because of camera problems most likely caused by high radiation levels.

It was the first time a robot has entered the chamber inside the Unit 2 reactor since a March 2011 earthquake and tsunami critically damaged the Fukushima Da-ichi nuclear plant.

Tokyo Electric Power Co. said it was trying to inspect and clean a passage before another robot does a fuller examination to assess damage to the structure and its fuel. The second robot, known as the "scorpion," will also measure and temperatures.

Thursday's problem underscores the challenges in decommissioning the wrecked . Inadequate cleaning, high radiation and structural damage could limit subsequent probes, and may require more radiation-resistant cameras and other equipment, TEPCO spokesman Takahiro Kimoto said.

"We will further study (Thursday's) outcome before deciding on the deployment of the scorpion," he said.

TEPCO needs to know the melted fuel's exact location and condition and other structural damage in each of the three wrecked reactors to figure out the best and safest ways to remove the fuel. It is part of the decommissioning work, which is expected to take decades.

Cleaner robot pulled from Fukushima reactor due to radiation
In this image released by Tokyo Electric Power Co. (TEPCO), a remote-controlled "cleaning" robot enters the reactor containment chamber of Unit 2 for inspection and cleaning a passage for another robot as melted materials are seen at Fukushima Dai-ichi nuclear power plant in Okuma town, Fukushima prefecture, northeastern Japan, Thursday, Feb. 9, 2017. The "cleaning" robot that entered one of three tsunami-wrecked Fukushima reactor containment chambers was withdrawn before completing its mission due to glitches most likely caused by high radiation. (TEPCO via AP)

During Thursday's cleaning mission, the robot went only part way into a space under the core that TEPCO wants to inspect closely. It crawled down the passage while peeling debris with a scraper and using water spray to blow some debris away. The dark brown deposits grew thicker and harder to remove as the robot went further.

After about two hours, the two cameras on the robot suddenly developed a lot of noise and their images quickly darkened—a sign of a problem caused by high radiation. Operators of the robot pulled it out of the chamber before completely losing control of it.

The outcome means the second robot will encounter more obstacles and have less time than expected for examination on its mission, currently planned for later this month, though Thursday's results may cause a delay.

Cleaner robot pulled from Fukushima reactor due to radiation
In this photo released by Tokyo Electric Power Co. (TEPCO), workers prepare to operate a remote-controlled "cleaning" robot at Unit 2 of Fukushima Dai-ichi nuclear power plant in Okuma town, Fukushima prefecture, northeastern Japan, Thursday, Feb. 9, 2017. The "cleaning" robot that entered one of three tsunami-wrecked Fukushima reactor containment chambers was withdrawn before completing its mission due to glitches most likely caused by high radiation. (TEPCO via AP)

Both of the robots are designed to withstand up to 1,000 Sieverts of radiation. The cleaner's two-hour endurance roughly matches an estimated radiation of 650 Sieverts per hour based on noise analysis of the images transmitted by the -mounted cameras. That's less than one-tenth of the radiation levels inside a running reactor, but still would kill a person almost instantly.

Kimoto said the noise-based radiation analysis of the Unit 2's condition showed a spike in radioactivity along a connecting bridge used to slide control rods in and out, a sign of a nearby source of high radioactivity, while levels were much lower in areas underneath the core, the opposite of what would normally be the case. He said the results are puzzling and require further analysis.

TEPCO officials said that despite the dangerously high figures, radiation is not leaking outside of the reactor.

Cleaner robot pulled from Fukushima reactor due to radiation
This undated photo released by Tokyo Electric Power Co. (TEPCO) shows a remote-controlled "cleaning" robot which is to be used for inspection inside the reactor containment chamber of Unit 2 at Fukushima Dai-ichi nuclear power plant. The "cleaning" robot that entered one of three tsunami-wrecked Fukushima reactor containment chambers on Thursday, Feb. 9, 2017, was withdrawn before completing its mission due to glitches most likely caused by high radiation. (TEPCO via AP Photo)

Images recently captured from inside the chamber showed damage and structures coated with molten material, possibly mixed with melted nuclear fuel, and part of a disc platform hanging below the core that had been melted through.

Cleaner robot pulled from Fukushima reactor due to radiation
In this Reactor Unit 2 stands at the tsunami-crippled Fukushima Dai-ichi nuclear power plant in Okuma, Fukushima Prefecture, northeastern Japan. A remote-controlled "cleaning" robot that entered the reactor containment chamber of Unit 2 on Thursday, Feb. 9, 2017, was withdrawn before completing its mission due to glitches most likely caused by high radiation. (Kyodo News via AP, File)

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Feb 09, 2017
Meanwhile, our little solar PV panels delivered 7.2 MWh of clean electricity for our house and EV in the first year of operation.

Feb 09, 2017
Meanwhile, Ivanpah solar plant is burning more and more natural gas to deliver electricity to gskam's house at night and cloudy days. It is a win-win game, for natural gas/fracking industry too.
"The behemoth Ivanpah solar power plant built with federal subsidies to combat climate change is using increasing amounts of natural gas, a greenhouse-gas-emitting fuel, state and federal data show."
"The most recent numbers from the California Air Resources Board show that in 2015, the plant's second year of operation, carbon emissions from Ivanpah's gas use jumped by 48.4 percent to 68,676 metric tons."
http://www.pe.com...pah.html
"Although natural gas burning emits less fatal pollutants and GHGs than coal burning, it is far deadlier than nuclear power, causing about 40 times more deaths per unit electric energy produced"
http://climate.na...r-power/

Feb 09, 2017
How much more will this revelation raise the estimated $190,000,000,000 cost and 40 years to "clean up" these disasters?

Feb 11, 2017
I got five "ones" for that question, but none of those folk could answer my question.

We have to face it, and the next one, as well.

Time to grow up.

Feb 11, 2017
I got five "ones" for that question, but none of those folk could answer my question.


Make that six (you're welcome)! Just speculating here, but perhaps no one answered your question not because no one was able, but because everyone is tired of engaging with you given your track record of dead horse-beating and dishonesty.

Time to grow up.


...said the pot to the kettle.

Feb 11, 2017
@STOLEN VALOR LIAR-kam
but none of those folk could answer my question
except that i've historically answered you, but you ignored it, as @SlartiBartfast noted
to which your replies dealt with no science and all sloganeering, refusing to address the issues and refusal to actually link references that invalidated the studies and links/references i used
Time to grow up.
if one cannot talk science, then one does not belong in a scientific discourse
you typically don't talk science yet you argue for people to stick to the science

so why did you never answer the simple question i posed back at you: which is more dangerous: flying at 33,000ft or standing within 6 meters of a nuclear reactor?

you claim technical superior training and nuke competence but still can't answer, but want everyone else to cow-tow?

so per your own request....

.

.

.

@SlartiBartfast
thanks for the great coastlines - loved those Fjords!
:-D


Feb 11, 2017
I got five "ones" for that question, but none of those folk could answer my question.
Because you ask that same question 5 or 4 times a day every day. Cher, if you have not got Willie-Skippy to answer you yet you must be dumb as a cypress stump to think if you ask for 1000th time you going to finally get an answer.

Feb 11, 2017
You can give no answer because the facts are inconvenient.

And no, Slartibrat, no dishonesty here. Only your need to hurt others.

Feb 11, 2017
And no, Slartibrat, no dishonesty here. Only your need to hurt others.


Slartibrat? Are you five?

More to the point, where exactly do you see me trying to hurt others. How have you extrapolated from this a diagnosis of an underlying psychological need to do so?

Feb 17, 2017
Absent any realistic solution to the disposal of these rapidly accumulating spent fuel rods, which emit vastly more hazardous radiation than fresh fuel rods, I submit that spent fuel rods are at least as hazardous to the planet as accumulating CO2.

There is no need to pollute the planet with either CO2 in the atmosphere or spent fuel rods in ever more cooling pools or temporary (relative to the spent fuel's lifetime) containers. As long as there remains any carbon-based fuels, whether fossil or renewable, crack them into carbon and hydrogen, put the carbon to use or just bury (sequester) it, and use the hydrogen to power fuel cells. The latter is what I've been doing for my Toyota Mirai's power, and processes for cracking have been known for decades and the work needed to make cracking practical is vastly simpler and less hazardous to the planet than building nuclear power stations. The only obstacle to cracking is getting cracking on actually doing it.

Feb 17, 2017
Speaking of winning technologies:

http://www.power-...01.html?

"Toshiba to Exit Nuclear Construction, Chairman to Resign"


Feb 17, 2017
Speaking of winning technologies:
coal is winning technology, thanks to faux-greens and antinuclear fearmongers.
"the volatile renewables don't always perform, and the Germans are also relying on coal- and gas-powered plants to keep the lights on." - Feb. 16, 2017
https://www.wsj.c...87241180

Feb 17, 2017
They are more concerned with safety than we are. We will both get to the production of clean power.

But nukes are being shown to be losers almost every week now.

Feb 17, 2017
Hey,Willie, if you go to the website I mentioned, you can see how they are closing the largest fossil-fueled generating plant in the West. We are cleaning up all over on this side of the country. Don't need no coal.

http://www.power-...01.html?

It is the story right after the one about Hitachi/Westinghouse quitting the nuke-building business.

Feb 17, 2017
...closing the largest fossil-fueled generating plant in the West ... Don't need no coal.
It will be replaced by natural gas/fracking.
As solar/wind farms have proven useless to curb CO2 emissions:
"Join the REAL Green Movement"
"Replace Every Wind Turbine With a Tree"
https://pbs.twimg...Oq4m.jpg
https://treesnott...tnt4.png
https://treesnott...mp;h=315

Feb 17, 2017
Hey,Willie, if you go to the website I mentioned, you can see how they are closing the largest fossil-fueled generating plant in the West
Hey if we go to your rinky dink website maybe we could see pics of your own roof with your PV panels on it, and your own driveway with your EV on it. Then everybody would have to say 'gee how wrong we were, george kamburoff is not really the idiot liar he made himself out to be.'

But that probably will never happen, eh george? Because you ARE the idiot liar you make yourself out to be. Riiiight?

Attention is worth humiliating yourself for isnt it?

Mar 04, 2017
This is of course a difficult dilemma money is always a hinderance, but you would think that when such a disaster happens (and hopefully is completely transparent) that the world would come together and provide a resolution and mutual consensus to take care of it with no cost involved.

The heros that initially put their lives behind the task at hand as an example ... can not volunteers on a rotation donate time and resources around the globe for all of mankind. I know its a naive idea.

Instead 6 years of runaway contamination - act with.

Mar 04, 2017
They pretty much did that in the Soviet Union for Chernobyl. Many gave their lives, knowing it, to stop that disaster.

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