Cleaner Robot Pulled from Fukushima Reactor Due to Immense Radiation

Megalith

Megalith

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Pop quiz: what happens when you put a robot rated to withstand 1000 Sieverts of radiation into an area that emits about 650 Sieverts of radiation per hour? Um, it gets fried pretty quickly. Obviously, we are depending on these little guys to get us out of the Fukushima mess, which houses radiation levels that would kill any person instantly, but it turns out that the toxic environment is doing quite the number on non-organics as well. Sadly, cleanup is expected to take “decades.”

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 radiation and temperatures. Thursday's problem underscores the challenges in decommissioning the wrecked nuclear plant.
 
I'm honestly surprised it lasted that long. It was working in the vicinity of a rather gaping hole in a catwalk when it took the high radiation reading. They were aiming to try and get closer to the hole to have a look into it and knew ahead of time it was possible the hole was actually caused by molten fuel escaping the reactor into the containment structure. There was speculation if this was the case, that the radiation levels would be much, much higher than the reading they reported. Under those conditions, the robot exceeded expectations.

This makes me wonder how exactly they intend on "cleaning up" the escaped fuel if nothing will survive long enough to work in that environment. There is a similar problem at Chernobyl (Pripyat). At least there, the molten fuel melted through the bottom of the reactor and mixed with sand in a chamber under it to form a lump of glass that can be removed one day when it is physically cool enough to handle. In the case of Fukishima, I believe the void under the reactor was filled with water (and this may have flashed to steam allowing the fuel to breach the bottom of containment).
 
They should call the liquidators back to work. They cleaned Chernobyl by hand.
 
B00nie said:
They should call the liquidators back to work. They cleaned Chernobyl by hand.
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No shit, watched a number of documentaries on Chernobyl and those poor bastards copped it bad. It was the same issue, the robots just kept dying.
 
hmm I've got it. When you build a new plant, make a 10km lead lined hole under the reactor core. When shit hits the fan, just pull the pins and let that fucker plummet towards oblivion, a few explosives go off along the way, collapsing the hole, case closed, thanks very much, give me my Nobel prize yeah?
 
Zuul said:
hmm I've got it. When you build a new plant, make a 10km lead lined hole under the reactor core. When shit hits the fan, just pull the pins and let that fucker plummet towards oblivion, a few explosives go off along the way, collapsing the hole, case closed, thanks very much, give me my Nobel prize yeah?
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Nice idea, problem is melted uranium would burn through that in no time.

The french (ariva) used to use a concrete pad under the reactor. If there was a meltdown, it would mix with the concrete. Not sure if that is still their way.

I've been following this story for a couple weeks now, and from what I gather the radiation fields increased to near meltdown levels...that makes me think fission started again. If enough rainwater or other source got in, it could act as a moderator and restart the reaction since this is enriched fuel. secondary meltdown? I hope not.
 
Don't worry, the Pacific Ocean is right there just 50 yards away. /Just sweep everything under the proverbial rug.
 
Gman1979 said:
I'm honestly surprised it lasted that long. It was working in the vicinity of a rather gaping hole in a catwalk when it took the high radiation reading. They were aiming to try and get closer to the hole to have a look into it and knew ahead of time it was possible the hole was actually caused by molten fuel escaping the reactor into the containment structure. There was speculation if this was the case, that the radiation levels would be much, much higher than the reading they reported. Under those conditions, the robot exceeded expectations.

This makes me wonder how exactly they intend on "cleaning up" the escaped fuel if nothing will survive long enough to work in that environment. There is a similar problem at Chernobyl (Pripyat). At least there, the molten fuel melted through the bottom of the reactor and mixed with sand in a chamber under it to form a lump of glass that can be removed one day when it is physically cool enough to handle. In the case of Fukishima, I believe the void under the reactor was filled with water (and this may have flashed to steam allowing the fuel to breach the bottom of containment).
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Fukushima site it is built upon a cliff excavation site. Tepco's engineers have already stated that groundwater flows from the countryside above the bluff, migrates under the plant, taking a subterranean path to the sea.
 
Zuul said:
hmm I've got it. When you build a new plant, make a 10km lead lined hole under the reactor core. When shit hits the fan, just pull the pins and let that fucker plummet towards oblivion, a few explosives go off along the way, collapsing the hole, case closed, thanks very much, give me my Nobel prize yeah?
Click to expand...

Personally, I'd rather see Liquid Fluoride Thorium Reactor research continued by the US. When a LFTR overheats it melts a freeze plug of frozen salt in a drain pipe and the core drains into a moderator tank. /It doesn't even require any intervention.

Not to mention that LFTR's can't run away. The reactivity decreases when the heat increases, left to it's own devices the reactor would just operate in a sine wave. Liquid fuels, no water cooling, is the ideal configuration (IMO).



 
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Lith1um said:
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Well I just blew 45 minutes watching that nuclear bomber discovery show. I guess I knew they tested stuff like this in the 50's-60's.... but man that seems just batshit crazy now. I like how Russia got theirs working but not giving a shit about the flight crew. Who needs radiation shielding? Just train more pilots. Yikes.
 
I know, right? I like how the Russian solution just flew along emitting radioactive isotopes right out the exhaust stream the entire time the engine was operational. 40 flights.
 
sieverts-copy.png


jesus....
 
Megalith said:
... rated to withstand 1000 Sieverts...
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Scorpion robo-machine was only expected to withstand 70 Sieverts not 1000,huge , huge difference, also the 650 number is an estimate based on gamma strikes to the camera before it failed
( they did not have an actual Geiger counter or scintillation reading ) and using the navy's system of estimating total radiation from gamma strikes, that 650 number would be multipled by ten, so 6,500....remember Sieverts are NORMALLY measured in milli-sievert ranges and somewhere between 7 to 10 whole sieverts is lethal.

For anyone just starting to follow this horror show of conclusion, incompetence and obfuscation that is fukushima daichii know that there are three complete melt outs ( units 1,2,3 ) and a waste storage pool fire at 4; the fuku site has been trying to store ( or decontaminate ) the cooling water which has generated a HUGE onsite tank and bag farm ( with an ambient out door , open air rating of about 3 Sieverts) , but still has been leaking 300 tons per day of contaminated water directly into the Pacific ocean 24/7/365 for SIX YEARS with no end in site .

a couple of good sites to get one up to speed :

http://www.fukuleaks.org/web/?cat=33

http://enenews.com/

http://www.thenuclearproctologist.org/
 
650 Sieverts! And that chart is in milli-Sieverts per hour so 1000 msv/hr = one sv/hr. Absolutely lethal.

If anyone is interested, UC Berkeley offers a course taught by Prof. Richard A. Muller which is titled, "Physics for Future Presidents". Imo, it is a fantastic lecture series which teaches the most interesting and important topics in physics, stressing conceptual understanding rather than math, with applications to current events. It is graciously hosted on YT by U.C. Berkeley. (Approximately 26 one hour lectures, with DL links in each lecture's description panel)



Full Playlist, https://www.youtube.com/playlist?list=PLNYKh_zBk1ESQJOJqBLeSUHgJaph6pCKO
 
Silverlok said:
Scorpion robo-machine was only expected to withstand 70 Sieverts not 1000,huge , huge difference, also the 650 number is an estimate based on gamma strikes to the camera before it failed
( they did not have an actual Geiger counter or scintillation reading ) and using the navy's system of estimating total radiation from gamma strikes, that 650 number would be multipled by ten, so 6,500....remember Sieverts are NORMALLY measured in milli-sievert ranges and somewhere between 7 to 10 whole sieverts is lethal.

For anyone just starting to follow this horror show of conclusion, incompetence and obfuscation that is fukushima daichii know that there are three complete melt outs ( units 1,2,3 ) and a waste storage pool fire at 4; the fuku site has been trying to store ( or decontaminate ) the cooling water which has generated a HUGE onsite tank and bag farm ( with an ambient out door , open air rating of about 3 Sieverts) , but still has been leaking 300 tons per day of contaminated water directly into the Pacific ocean 24/7/365 for SIX YEARS with no end in site .

a couple of good sites to get one up to speed :

http://www.fukuleaks.org/web/?cat=33

http://enenews.com/

http://www.thenuclearproctologist.org/
Click to expand...

 
On a somewhat related note, take a look at primitive 1978 era technology use to clean up the Three Mile Island meltdown. Basically chisels and scoops with really long handles, shielded by water. /Which almost certainly wouldn't work at Fuku.



 
The camera didn't malfunction, the radiation made the robot sentient and it started to panic!

On a serious note, this shit is scary and I hope they can figure out a way to contain it or clean it.
 
We've had fail-safe nuclear plants for decades. Boggles the mind that we're still using LWR instead of HWR. Fear and ignorance are holding us back.
 
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