Robot's attempt to get sample of melted nuclear fuel at Fukushima reactor suspended

*The work was stopped when workers noticed that five 1.5-meter pipes used to maneuver the robot *were placed in the wrong order

Are these Japan’s brightest? — the same jokers who created this problem in the first place by clearing away the existing Pacific-facing 35-meter bluff that would have been the Fukushima No. 1 nuclear plant’s natural protection against a tsunami?

Trying to remove radiation material in the heights of Typhoon season,is something the village would fo

Definitely regrettable, as this is a key step, but the work will go on.

YrralToday 06:20 pm JST

Trying to remove radiation material in the heights of Typhoon season,is something the village would fo

Nothing to do with typhoons.

Attempting to do something never tried before.

What is the radiation level inside the No2 reactor?

"The radiation level inside the containment vessel of the No. 2 reactor is several tens of sieverts per hour, enough to kill most people within a few minutes. "

They are trying to remove 3 grams of 850 tons of corium.

"...an estimated 880 tons of fatally radioactive molten fuel...."

Let's see, 880 tons times 2000 pounds per ton means there are 1,760,000 pounds of molten radioactive fuel. And the effort to remove 3 ounces seems insurmountable. How many millions of yen have been spent in the effort to remove 3 ounces of the molten radioactive fuel?

Good to know the clean-up effort is going so smoothly.

Do like the Russian did encase it in cement

To date, the money spent is about ¥20 trillion. The eventual costs will be Y80-¥100 trillion.

And this is one of the simple reasons why nuclear power will never be green despite all the nuclear fanatics trying to convince you other wise.

Time limit for radiation exposure? For a robot?

For once I agree with Yrral. On both counts.

The work was stopped when workers noticed that five 1.5-meter pipes used to maneuver the robot were placed in the wrong order and could not be corrected within the time limit for their radiation exposure,

This level on incompetency and stupidity should never be allowed on a Nuclear powerplant. If those are the brightest engineers that supervise the Japanese nuclear power plants....

TEPCO is a sham and they should never be allowed to operate Nuclear plants without supervision again.

five 1.5-meter pipes used to maneuver the robot were placed in the wrong order

The engineers should have known the plan, practiced the plan, and repeatedly rehearsed the plan — particularly with the entire nation and its press watching.

This reeks of incompetence. Can these people be trusted around nuclear energy?

metric tons. add 10% when converting to pounds. mixing and converting units is how mistakes happen.

robot cameras and electronic controls are severely damaged in such high radiation. life of cameras used so far are measured in minutes.

not enough information about the construction, differences and tolerances of the pipes. leaping to conclusions doesn’t solve anything.

if the engineers are so stupid, use your nuclear and mechanical engineering experience in an unprecedented retrieval of material so radioactive that a person would be dead in minutes and go tell them how to do it.

a manned mission to mars is easier than this task.

konjo4uToday 07:56 pm JST

Time limit for radiation exposure? For a robot?

To add to what Peter Neil said, it's the same when probes are sent into space: radiation shielding is needed as electronics are damaged by radiation.

DanteKHToday 08:12 pm JST

This level on incompetency and stupidity should never be allowed on a Nuclear powerplant.

Problems due to human error can happen at any kind of facility, anywhere in the world. It's human nature.

But TEPCO is unquestionably at fault here, and its processes need to be reviewed.

when designing and manufacturing technically sophisticated and complex electro-mechanical products, i always found it helpful to listen to people who couldn’t build a bookshelf.

It's a big fake! PIckintp the dipri nonsence! Just a pretext for the demotion of the the reactor.

But no hope about it. Tepco should be honest in its uncapablity to deal with it,

It is better and practcal to block and cover with fixed and hard materials.

Info on the robot and the operation

Fukushima Daiichi Nuclear Power Station

Unit 2 PCV Internal Investigation/

Preparation Status of Fuel Debris Trial Retrieval

https://www.tepco.co.jp/en/hd/decommission/information/newsrelease/reference/pdf/2024/reference_20240425_02-e.pdf

If they aren't simply going to encase the entire thing in situ and hope for the best, they may need a more analogue, steampunk alternative to cope with the radiation. Hoists, pulleys, cogs, rope, use of gravity.

We may not have the technology to deal with this for some time - decades maybe. And then they have to find somewhere to safely store it. Any volunteers?

A worry is that tech development and innovation is being plateaued by governments on political and environmental grounds, so the pace of innovation may now slow down.

The obvious take away is that you shouldn't turn anything on if you might not be able to safely turn it off again.

On the bright side, we are always told that nuclear power is the cheapest and cleanest energy, so this is presumably costing very little and not endangering anyone.

Chernobyl and Fukushima are two very different types of nuclear disasters and two very different types of locations. Fukushima cannot just be covered with concrete.

NHK has a good video explanation showing five pusher rings, like donuts, with a cable passing through them. The front ring was misplaced, out of sequence.

(Tried to paste URL but failed.)

The incompetence at TEPCO is aggravating and never ending.

satoshi matsudaToday  09:35 pm

But no hope about it. Tepco should be honest in its uncapablity to deal with it,

i agree.

i built electrical systems for nuclear plants. my degree is in mechanical engineering with a specialization in nuclear power.

the unfortunate truth is the government is dictating what tepco says and does. it has minimized the radiological impact to the public and land in the area.

the ocean is virtually unaffected because the alps system has been a technical success in treatment of contaminated water.

however, the government was irresponsible in choosing to not build a sarcophagus years ago. the permanent sarcophagus would be a permanent reminder that the area is unsafe. which it is.

but the government wants to maintain the image that the region can be “fixed” and life can return to normal. it’s happy talk by bureaucrats worried more about image than substance.

i’m certain soil contamination and the volume of airborne radiological release was more than reported.

i lived (downwind) about 90 miles from the plant. we received a heavy dose in the area i lived.

i immediately started my plan to leave japan after almost 20 years in japan. i left.

the quake and tsunami, the fukushima disaster (disaster is the proper term) all brought reality to the forefront that a major quake in kanto/tokyo would/will bring incredible suffering in a system where the just in time supply chain will collapse.

tepco engineers are trying to do something almost impossible. they were told to develop some unknown and yet to be developed technology to save the day.

we can’t change the past, but public relations and happy talk is not a solution.

i apologize for this extra post, but tepco senior management and top government regulatory people should still be in prison today. it was extraordinary criminal negligence not moving the backup electrical system to higher ground as recommended.

it's a national disgrace that it did not happen.

i immediately started my plan to leave japan after almost 20 years in japan. i left.

Did you come back?

 it was extraordinary criminal negligence not moving the backup electrical system to higher ground as recommended.

How many cleanup decades and trillions of yen could have been saved by this simple and sensible measure?

YrralToday 07:35 pm JST

Do like the Russian did encase it in cement

Most likely the cause of the ground water contamination which will not stop until removed. If the foundation base has been compromised, encasing in concrete will do no good. May also be a risk that from another earthquake, material could be moved so that there is enough together to cause a fire again.

DizLassToday  11:20 pm JST

i immediately started my plan to leave japan after almost 20 years in japan. i left.

Did you come back?

no. my wife died, so japan doesn't have the same feel.

 it was extraordinary criminal negligence not moving the backup electrical system to higher ground as recommended.

How many cleanup decades and trillions of yen could have been saved by this simple and sensible measure?

all of it? :) we wouldn't have this topic to discuss.

The collection of a tiny sample of the debris inside the Unit 2 reactor’s primary containment vessel would start the fuel debris removal phase

It would be good to start the removal phase, and even now, they won't really know what they are dealing with until they get a sample and an exact picture of what they are dealing with. Plus, they most likely still don't have the tools to work in the extremely high-radiation environment, in which it is hard for even robots to survive. Fortunately, Japan is a quiet place with no earthquakes or tsunamis to worry about...

Even a robot knows better.

@Wallace.

Understood. What I'm getting at is that if electronics isn't going to cope, they need to use a non-electronic solution, so instead of a robot, a marionette.

Pre-electricity craftsmen built remarkably complex automata. They may need to operate one of these at distance using cables like a puppet.

GBR48

Understood. What I'm getting at is that if electronics isn't going to cope, they need to use a non-electronic solution, so instead of a robot, a marionette.

> Pre-electricity craftsmen built remarkably complex automata. They may need to operate one of these at distance using cables like a puppet.

The control and electronics are in that huge machine with pipes entering the reactor. Like a probe.

Time limit for radiation exposure? For a robot?

Yes. That much radiation is murder to the electronics.

Pre-electricity craftsmen built remarkably complex automata. They may need to operate one of these at distance using cables like a puppet.

You still need lighting and a camera. Radiation is really hard on any kind of electronics.

about 11 years before, the then Japanese PM told lies such as "situation is under control" about Fukushima nuclear disaster to bid Olympics.

2006, 5 years before Fukushima disaster, he had done optimistic answer also about nuclear disaster risk at the Diet, its inconsideration was one of causes that insufficient safety measures were neglected.

Understood. What I'm getting at is that if electronics isn't going to cope, they need to use a non-electronic solution, so instead of a robot, a marionette.

Or human robots? Lead lined suits, two pairs of gloves and some left over covid face masks. Limit the time in the facility to a few minutes. Offer twice the minimum wage and unlimited free green tea and rice balls. Should be able to get enough volunteers or foreign "trainee" workers.

TEPCO has cancelled the corium extraction.