Robot probes show Japan reactor cleanup worse than expected

February 17, 2017 by Mari Yamaguchi
This Feb. 16, 2017 photo released by Tokyo Electric Power Co. (TEPCO) shows a remote-controlled "scorpion" robot inside the Unit 2 reactor's containment vessel at Fukushima Dai-ichi nuclear power plant in Okuma town, Fukushima prefecture, northeastern Japan. Robot probes sent to one of Japan's wrecked Fukushima nuclear reactors have suggested worse-than-anticipated challenges for the plant's ongoing cleanup. (TEPCO via AP Photo)

Robot probes sent to one of Japan's wrecked Fukushima nuclear reactors have suggested worse-than-anticipated challenges for the plant's ongoing cleanup.

The plant's operator Tokyo Electric Power Co. said the remote-controlled "scorpion" robot was sent into the Unit 2 reactor's containment vessel Thursday to investigate the area around the core that had melted six years ago, but its crawling function failed while climbing over highly radioactive debris.

The robot, carrying a dosimeter, thermometer and two small cameras, transmitted some data and visuals but could not locate melted fuel—key information to determine how to remove debris out of the reactor. The robot was abandoned inside the vessel at a location where it won't block a future probe.

Preliminary examinations over the past few weeks have detected structural damage to planned robot routes and higher-than-expected radiation inside the Unit 2 containment chamber, suggesting the need to revise robot designs and probes.

Similar probes are being planned for the two other melted reactors. A tiny waterproof robot that can go underwater will be sent to Unit 1 in coming weeks, but experts haven't figured out a way to access badly torn Unit 3.

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.

Despite the incomplete probe missions, TEPCO stuck to its schedule to determine methods for the melted fuel removal this summer and start work in 2021, company spokesman Yuichi Okamura said.

TEPCO is struggling with the plant's decommissioning, which is expected to last decades, following the 2011 earthquake and tsunami that led to the meltdown. Tens of thousands of residents had evacuated their homes, many of them still unable to return due to high radiation.

Earlier this month, another robot, designed for cleaning debris for the main "scorpion" probe, had to return midway through because two of its cameras became inoperable after two hours when its total radiation exposure reached a maximum tolerance of 1,000 Sievert—a level that can kill a human within seconds. The original duration planned for the robot was 10 hours, or 100 Sievert per hour.

Inadequate cleaning, high radiation and structural damage could limit subsequent probes, and may require more radiation-resistant cameras and other equipment, TEPCO officials said.

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

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

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gkam
1.5 / 5 (8) Feb 18, 2017
The more we find out, the worse it gets.

The estimated $190,000,000,000 cost to deal with these disasters will certainly go way up now.

Want a guaranteed future? Get into nuclear disaster remediation.

There is simply no excuse for nukes anymore.
1sonnyc
not rated yet Feb 18, 2017
If doctors can replace heart valves going thru veins without using robots. I would love to see Japan get over the robot tech fuss and design an up scaled endoscopy type solution. You might need machines to run arms thru cables to apply enough forces but it would be more resistant to radiation. Imagine a few entry points, using single purpose tools. Something like that might even perform well for bigger cleanup tasks. Wish I had the time and money I would try and prototype something
WillieWard
3 / 5 (4) Feb 19, 2017
There is simply no excuse for intermittent renewables anymore. In Germany: the wind plants and the solar plants, are coal plants.
"Public exposed to far more radiation from coal plants than nuclear stations, says report:"
http://www.world-...174.html
"Report: Germany suffers more coal-linked deaths than rest of EU"
"Germany – home to the much-hailed 'Energiewende' green revolution – suffered more premature deaths linked to coal plant pollution than any other EU member state, research by health and environment campaigners has found."
https://www.eurac...t-of-eu/
"Japan's coal-fired plants 'to cause thousands of early deaths'"
https://www.thegu...eenpeace
gkam
1.6 / 5 (7) Feb 19, 2017
Yup, coal and nukes are nasty stuff, which is why we are ridding ourselves of them here.

But no coal or gas plant has created such a disaster as a Chernobyl or a Fukushima. Let's face it, you folk are in over your silly little heads, playing with something bigger than you.

We will have to take it away.
WillieWard
3.4 / 5 (5) Feb 19, 2017
But no coal or gas plant has created such a disaster as a Chernobyl or a Fukushima.
"Chernobyl killed 54 people after 30 years, a bad coal smog in the UK killed 3,000 Brits in one summer", Fukushima: "zero deaths by radiation"
But no coal or gas plant has created such a disaster as a Chernobyl or a Fukushima.
It' ironic to see antinuclear fearmongers/faux-greens defending the fossil fuel industry. The Greenie movement is pathetic and hypocritical!
gkam
1.6 / 5 (7) Feb 19, 2017
Admit it, Willie, you folk are in over your head, trying to deal with something much bigger than you and the nukers. You failed to give us safe power, and instead gave us disasters, gave us radioactive pollution, gave us debt.

Nuke technology has already killed Westinghouse Nuclear, costing them $9,000,000,000 so far.

Meanwhile, my power comes from the PV on my roof.
WillieWard
3 / 5 (4) Feb 19, 2017
"These Clean Energy Projects Pollute More Than Coal Power Plants"
"Geothermal wells usually provide a steady supply of clean energy flowing from the natural heat of the Earth. In Turkey, because of a quirk in the geology, some of those wells pollute as much as coal-fired power plants."
https://assets.bw...0x-1.png
https://www.bloom...r-plants
WillieWard
3 / 5 (4) Feb 19, 2017
Meanwhile, my power comes from the PV on my roof.
"it's not a lie if you believe it".
http://s3.postimg...9099.jpg
gkam
1.6 / 5 (7) Feb 19, 2017
Gosh, Willie,send me an email address, and I'll send you some pics of it.

My system is real and it is earning me 22% per year of investment. And since gasoline and power are going up, this investment is worth more every year.

Like to have a house and car with no gasoline or electricity bill?
gkam
1.6 / 5 (7) Feb 19, 2017
Willie, wasn't that supposed to be a picture of Trump saying that?
Uncle Ira
5 / 5 (6) Feb 19, 2017
Willie, wasn't that supposed to be a picture of Trump saying that?


All you had to do was ask Cher, here you go,,,,,

https://dummr.fil...pg?w=500
gkam
1.6 / 5 (7) Feb 19, 2017
Thnx.

I should have looked for it.
TheGhostofOtto1923
3.7 / 5 (6) Feb 19, 2017
Gosh, Willie,send me an email address, and I'll send you some pics of it
Gosh liar, post your pics on your website instead sending out fake pics to a select few, so that we may all see them and then have to admit that you are not the liar we all know you are.

That sounds reasonable doesnt it? Something someone real would do, yes?
Whydening Gyre
3.7 / 5 (6) Feb 20, 2017
Yup, coal and nukes are nasty stuff, which is why we are ridding ourselves of them here.

But no coal or gas plant has created such a disaster as a Chernobyl or a Fukushima. Let's face it, you folk are in over your silly little heads, playing with something bigger than you.

We will have to take it away.

What about all the deaths from just coal mining, George? Way more than Chernobyl or Fukoshima.
Anyway, you put way more fear into it than you should.
It's an on-going process.
Sure it's dangerous, but so is sex. Do you stop THAT?
Adapt and move on. Evolve.

WillieWard
4 / 5 (4) Feb 20, 2017
There is simply no excuse for intermittent renewables anymore. In Germany: the wind plants and the solar plants, are coal plants.
"Germany's Energy Mistakes Are Hurting Its Neighbors Too"
"that's what's happening in Germany right now, where headlong subsidization of renewable energy has not only produced some of the highest electricity bills in Europe, but has also threatened the stability of power grids in Poland and the Czech Republic"
"wind and solar power are intermittent—they can only supply the grid when the sun is shining and the wind is blowing. On especially sunny or windy days, that can mean a sharp spike in supplies that doesn't just strain Germany's grid, but also those of its neighbors"
"now Poland and the Czech Republic are having to contend with blackouts, unstable grids"
"Believe it or not, this is not what a successful energy policy looks like"
http://www.the-am...bors-too
gkam
1.6 / 5 (7) Feb 20, 2017
"Sure it's dangerous, but so is sex. Do you stop THAT?"
-----------------------------------------
WG, want work?

You know where they need you.

What are you waiting for, the next disaster? Do you think there will not be another?
antialias_physorg
5 / 5 (2) Feb 20, 2017
Robot probes show Japan reactor cleanup worse than expected

Now, there's a big surprise (/sarcasm)

If doctors can replace heart valves going thru veins without using robots. I would love to see Japan get over the robot tech fuss and design an up scaled endoscopy type solution.

The distances involved are rather large. It's not like the controller can be in the next room or so.
gkam
1 / 5 (6) Feb 20, 2017
Perhaps research into finding materials to protect the robots can lead to better protection for space travelers. The science of robotics will certainly improve.
Whydening Gyre
5 / 5 (2) Feb 20, 2017
"Sure it's dangerous, but so is sex. Do you stop THAT?"
-----------------------------------------
WG, want work?

You know where they need you.

What are you waiting for, the next disaster? Do you think there will not be another?

If they want my unique expertise, they'll call me...
Da Schneib
5 / 5 (4) Feb 20, 2017
Can we please stop talking about Sieverts, which are a biological measurement, and start talking about Grays, which are a measurement of detected radiation, now?

C'mon physorg, this has been commented in another article. Are we paying attention yet?

As far as substantive comment on the article, I'd say it's pretty obvious they've got a heck of a mess on their hands (and that's way polite). This is what lack of oversight and lack of professionalism and inclusion of accountants in the decision cycle breeds. This is a technological arena that requires discipline on the order of that we require of those who carry weapons to defend our countries. Not a bunch of accountants cutting costs without taking the risks into account. Soldiers don't go running off and start shooting people because they have guns. Nuclear engineers can't start cutting safety because the accountants tell them to.

[contd]
Da Schneib
5 / 5 (2) Feb 20, 2017
[contd]
I won't be surprised if some Japanese ask why these accountants aren't committing seppuku if they're so samurai and stuff. And the managers who let them do this. Who's in charge, anyway? How come they're not taking responsibility for their screwups, like any good samurai should?

One can argue that the USSR fell because of Chernobyl. This stuff has consequences, on the scale of nations. It's time it was treated like dams are; if a dam fails, there will be a flood and millions of people can die. I don't argue against nuclear energy, but dammit it needs to be *regulated*.
Da Schneib
5 / 5 (1) Feb 20, 2017
And in case anyone thinks I'm dissing Japanese, that's actually equivalent to criticism I'd level against US banking executives as well. It's not a problem with a national pedigree; I'm just putting it in the terms the executives choose themselves. And I know there are Japanese activists who put it in those terms too. And well they should.

I expect when the Fukushima cleanup is done, it will turn out to have cost Japan more than all the electricity it generated. And I think that's a shame; I like Japan.
Whydening Gyre
Feb 20, 2017
This comment has been removed by a moderator.
antialias_physorg
5 / 5 (4) Feb 21, 2017
How come they're not taking responsibility for their screwups, like any good samurai should?

That's a bit of a political issue. TEPCO managers have a long history of...erm...going into politics after 'retiring' (and vice versa).

it will turn out to have cost Japan more than all the electricity it generated

This is always true - even of fossil fuels. The real question is: of whom would it have cost more. Privatize profits - socialise costs. Technologies that produce waste (which aren't accounted for in the production/monetization process) are basically means of channeling funds from those who clean up in post to those who sell the stuff up front.

Sometimes I think this is the real basis that capitalism runs on. And it workesd well as long as the garbage dumps were deep enough so no one noticed. However our garbage dumps (soil, atmosphere, oceans) seem to be full of shit now (from CO2 to radionucleids. Time to pay the price.
Eikka
3.7 / 5 (3) Feb 25, 2017
Can we please stop talking about Sieverts, which are a biological measurement, and start talking about Grays, which are a measurement of detected radiation, now?


Again, Sieverts are absorbed equivalent dose while Gray is incident radiation dose. It's perfectly reasonable to use Sieverts, especially when 1 Sv = 1 Gy in the gamma/beta/x-ray.

Using Gray wouldn't be meaningful because it doesn't tell you how much energy is being absorbed into the device. The robot is totally insensitive to alpha radiation because it's sealed in metal, so applying 1000 Gy of alpha on it would result in 0 Sv actual dose. That's the difference.

When you go from Gy to Sv you apply different weights for the different types of radiation, and you can change the weights, and you have to change it even with humans being the target because the equivalent dose is different when you've been exposed e.g. on the arm than on the groin or head.
Eikka
5 / 5 (2) Feb 25, 2017
Sometimes I think this is the real basis that capitalism runs on. And it workesd well as long as the garbage dumps were deep enough so no one noticed.


Sometimes? It's how all systems of economy have run so far because it's been possible.

Non-capitalist systems have a worse track record though because the states controlling the means of production simply treat their people as numbers - they're unable to handle the question any other way since they can't afford to give the people any actual power or voice - after all the common rabble need an enlightened "vanguard" to take care of their best interest. For reference, see Lake Karachay.

Under capitalism the people at least serve a purpose as consumers: you can't have a market without buyers, so you can't just ignore the people in search of profit. Forgetting that would be neoliberalism - Thatcherism essentially.
gkam
1 / 5 (5) Feb 25, 2017
Well, it ain't Capitalism which has to clean up the three Fukushima disasters, it is the government now, since they are also controlled by the large corporations in Japan. It means the cost will be paid by the victims, not the perpetrators of the disasters.

A thousand Sieverts? It only takes a few to kill you. So far they cannot make machines which can stand up to the radiation.

Why did we let them do this? Why do we allow more nukes?
Da Schneib
2 / 5 (4) Feb 25, 2017
Sieverts are absorbed equivalent dose
Sieverts are specifically a measure of the expected amount of tissue damage in a human. They have nothing to do with robots.

Absorbed dose is measured in Grays. Grays may be converted into Sieverts based on various factors such as the type of radiation and the known physiological effects. It's totally useless to give Sv dosage for a robot. Gy dosage is the important number.

Please stop posing, @Eikka.
WillieWard
2.3 / 5 (3) Feb 25, 2017
It only takes a few to kill you.
but no one has been killed.
Be calm, gskam, tinfoil hats protect you from any kind of radiation.
https://uploads.d...8ea9.jpg
https://fsmedia.i...cies.png
http://dogknobit....012h.jpg
https://uploads.d...cd85.jpg
https://uploads.d...4e7c.jpg
Da Schneib
5 / 5 (2) Feb 25, 2017
Under capitalism the people at least serve a purpose as consumers:
So they're not very important, right? It's the corporate states that are important.

I'm personally insulted you think I'm not important. I don't think you're important either, @Eikka.
gkam
1 / 5 (5) Feb 25, 2017
It is not up to you to restrict others, Schneib. Settle down.

They had a reason for using Sieverts, as it will be humans they are most concerned with, and probably want to put in that perspective.
Eikka
5 / 5 (1) Feb 27, 2017
Sieverts are specifically a measure of the expected amount of tissue damage in a human.


Wrong. It was designed for that, but there is absolutely no problem in using them for robots. Again, I point out: if you expose the robot to 1000 Gy of alpha radiation, nothing happens. If you expose it to 1000 Gy of gamma radiation it breaks down. How to put those two together in a single number that tells you how much radiation the robot can handle? By applying different weights for different types of radiation exposure. What do you get when you do that - Sieverts.

Sieverts measure the imparted energy, Joules per kg. It's does NOT measure "amount of tissue damage" as there is no such constant measure of damage per Joule.

The amount damage is merely inferred from how much energy on what part of your body was recieved, according to some fudge factor such as the LNT model which is largely inaccurate at low doses.
Eikka
5 / 5 (1) Feb 27, 2017
So they're not very important, right? It's the corporate states that are important.

I'm personally insulted you think I'm not important. I don't think you're important either, @Eikka.


"Corporate states" does not describe capitalism or the free market - in fact it's the antithesis of them because the state is not supposed to take part in the market; that's called crony capitalism.

And it's got nothing to do with who feels themselves important. It's a question of feedback: free markets have feedback in the form of the peoples' purchasing power or lack thereof, whereas non-free systems do not because they're top down dictatures: the leadership is either unwilling or unable to care.

Even with "democratic dictature" where people try to exercise their "positive liberty" to regulate themselves and direct the economy, the information flow is severily restricted by what the few individual representatives in power can see, and want to see.

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