Massive 8.9 earthquake and tsunami devastate Japan

fade

Staff member
The OED agrees with Adam. I think the problem might be solved by changing the word "nuclear" rather than "accident".

The quoted paragraph above regarding the train is a bit of a non-sequiter. You wouldn't refer to that as a train accident because the character of the accident doesn't involve anything inherently "train-y". The danger to life and damage to property were the direct result of the water from the tsunami. It is appropriate to assign the blame or emphasis to the tsunami. In contrast, the danger to life and property from the power plant are inherently nuclear, and not the direct result of the tsunami. It is therefore appropriate to assign action to the nuclear side.

A counter analogy to the train damage might be to consider a train hitting a car, which then hits a pedestrian. Calling the nuclear incident a tsunami thing would be kind of like saying the pedestrian was hit by the train.

In the end it's psychological damage control, and unfortunately people have such a fear of nuclear power as it is, that the overreaction to the use of the term "nuclear accident" probably is warranted (despite everything I just said). Logic is irrelevant in this type of situation, so it really doesn't matter what "accident" logically translates to if the objective is to prevent a gut uprising against nuclear power.
 
In the end it's psychological damage control, and unfortunately people have such a fear of nuclear power as it is, that the overreaction to the use of the term "nuclear accident" probably is warranted (despite everything I just said). Logic is irrelevant in this type of situation, so it really doesn't matter what "accident" logically translates to if the objective is to prevent a gut uprising against nuclear power.
This is the heart of what I was getting at, but fade said it so much better than I ever could.
 
http://www.bbc.co.uk/news/science-environment-23779561

The Japanese nuclear energy watchdog raised the incident level from one to three on the international scale that measures the severity of atomic accidents. This was an acknowledgement that the power station was in its greatest crisis since the reactors melted down after the tsunami in 2011. But some nuclear experts are concerned that the problem is a good deal worse than either Tepco or the Japanese government are willing to admit. They are worried about the enormous quantities of water, used to cool the reactor cores, which are now being stored on site.

Some 1,000 tanks have been built to hold the water. But these are believed to be at around 85% of their capacity and every day an extra 400 tonnes of water are being added.

"The quantities of water they are dealing with are absolutely gigantic," said Mycle Schneider, who has consulted widely for a variety of organisations and countries on nuclear issues. What is the worse is the water leakage everywhere else - not just from the tanks. It is leaking out from the basements, it is leaking out from the cracks all over the place. Nobody can measure that."
 
http://www.cnn.com/2013/08/27/world/asia/japan-fukushima-leak-warning/index.html?hpt=hp_t2

Toshimitsu Motegi, the industry minister, said Monday after visiting the plant that "from now on, the government is going to step forward." His ministry has been tasked by Prime Minister Shinzo Abe to come up with measures to tackle the mounting problems at Fukushima Daiichi.
Yes, this entire time the government has been monitoring the situation, and only now feels it may be time to step in. For the last 900 days, or 2.5 years, the only entity standing between worldwide environmental radiological disaster is a power company. A company that is not yet bankrupt only because Japan gave them 1 trillion yen (~$10 billion[USD]) last year.

The broken reactors are not yet cold. Without active cooling they will heat up and crack or destroy their containment vessels, releasing radioactive gasses into the air. The cooling systems are damaged, so any cooling water used becomes radioactive. They cannot clean the water at a rate anywhere near their usage rate. They have been, and continue to, build "temporary" water storage on site to hold the contaminated water. If you've got thousands of temporary water containers, eventually one or more will leak, and this is where the current leaks (that they are admitting to, anyway) originate from.

So a committee has been formed to consider whether the government should intervene. Which is apparently a big step forward. Or so they tell us.[DOUBLEPOST=1377704088,1377703839][/DOUBLEPOST]Do note that the money Japan gave the company in 2012 was an investment, and gave Japan 50.11% of the company - a controlling vote. They just haven't used that power yet.

Also note that in 2012 due to growing public distrust nearly all Japanese nuclear reactors were closed.

http://en.wikipedia.org/wiki/Nuclear_power_in_Japan

However this is meant to be temporary, and they are working on restarting many, if not all, of them, over time.

http://spectrum.ieee.org/energy/nuclear/japan-prepares-to-restart-nuclear-plants
 

GasBandit

Staff member
I'm not a nuclear scientist, so perhaps someone here who knows better can illuminate me - is there a detriment to cooling a reactor with water that is already radioactive? I am guessing the water is mostly (except for the damage, obviously) kept outside the reactor housing, so does it increase the reaction intensity to a great degree just flushing it through and out again?
 
I'm not a nuclear scientist, so perhaps someone here who knows better can illuminate me - is there a detriment to cooling a reactor with water that is already radioactive? I am guessing the water is mostly (except for the damage, obviously) kept outside the reactor housing, so does it increase the reaction intensity to a great degree just flushing it through and out again?
I was wondering that as well. They can't use the usual cooling setup where they expose the water to air in cooling towers and let steam carry away most of the heat, but couldn't they use a heat exchanger which transferred the heat from a radioactive cooling loop to a nonradioactive cooling loop, then use either seawater, air cooling, or another normal method to cool them down?

My guess is that they were hoping to use very cold seawater to cool the reactors down far enough to fix them, and using that water very directly in the core would result in the greatest amount of heat taken away the most quickly. However they haven't cooled them down far enough, but there's enough progress that they think it is still the best solution. Any other cooling method would be much slower. So the question perhaps was go with a safer cooling technique that took longer (and extended the risk out to many more years) or go with a riskier cooling technique that cooled it more quickly.

It could also be that it isn't even a choice - no other cooling technique may be able to keep up with the heat output. Keep in mind that at least one of the reactors is completely melted down - it's probably generating significantly more than its rated maximum of 780MW of heat continuously, with no methods to slow the reaction down they may only have one choice for preventing further containment building breaches. If this is the case, they pretty much would have to bring the plant back online with multiple gigawatt heat exchangers and cooling towers - far more than was required when the reaction could be controlled - and perhaps more than they can bring back up quickly.

Further, no workers are allowed on site for any significant length of time. The plumbing and everything else is still a mess.

But I'm literally just making this up. I don't see any other reasons they might have chosen this route, but I'm only taking a stab in the dark.
 
I'm not a nuclear scientist, so perhaps someone here who knows better can illuminate me - is there a detriment to cooling a reactor with water that is already radioactive? I am guessing the water is mostly (except for the damage, obviously) kept outside the reactor housing, so does it increase the reaction intensity to a great degree just flushing it through and out again?
I'm pretty sure that repeatedly using the same water would eventually irradiate it to the point that we couldn't clean it and/or it becomes incredibly difficult to store... and it's not like they can just flush the stuff out when they are done with it.

As for the previous comment about how many nuclear reactors were shutdown in Japan after the incident... this is actually a very bad thing because it's required Japan to switch to coal, oil, and natural gas plants, which has only increased their pollution problem. It also exacerbated an already overtaxed power system. I understand why they are upset, but the reason the Fukushima accident happened was...

- Because of a perfect storm. It got nailed with a Tsunami AND a high intensity earthquake. The fact that the building withstood any of it is a marvel.

- More importantly, because TEPCO had been lying about the safety status of it's reactors for years because it wasn't willing to pay for the repairs and upgrades it needed. Because this is Japan and accusing someone of lying is kind of a big deal there, what ended up happening is everyone just accepted the lies because to do otherwise would be making waves. You make waves in Japan, your company rubber room's you or worse.

... and shutting down the reactors does nothing unless they can provide an alternative source of power or fix the old reactors. It's just making the problem worse.
 
So, I too am no nuclear physicist and must ask, on a scale of 1 to 10 in light of this new info, how fucked are we?
It's pretty bad. The Japanese government and TEPCO will drag their feet and try to downplay the problem to save face, while making some half-hearted efforts to fix the problem. If it works, then good. But it's more likely it will be a continuing problem for years, until it eventually gets so bad that the international bodies step in to fix it.
 
Leaking radioactive water into the sea in amounts that measurably increase the radiation across an ocean is not good.

It won't end the world. Some people will have an increased chance for cancers, and if too much leaks we'll be told not to eat fish from some parts of the sea.

It's not yet enough to appreciably affect birth defects outside Japan. Don't know about inside Japan, though, particularly near the plant.
 
Leaking radioactive water into the sea in amounts that measurably increase the radiation across an ocean is not good.

It won't end the world. Some people will have an increased chance for cancers, and if too much leaks we'll be told not to eat fish from some parts of the sea.

It's not yet enough to appreciably affect birth defects outside Japan. Don't know about inside Japan, though, particularly near the plant.
Their birth rates are already being, presumably, affected by the plastic the fish are eating.
 
... Great, I'm near Japan. I'll be mutating and sprouting tentacles any day now.
What, after getting married? You're reading the pervert's handbook upside-down again, aren't you? :p


Anyway, yeah, it's a big problem, and we're all kind of fucked. The estimated amount of leaked radiation is being talked about in multiples of Tchernobyl. As in, "oh, today we've only allowed 1/10th of a Tchernobyl out into the ocean untreated". The ocean's ap retty big place, but it's still going to bite all of us in the ass at high speed.

It's not being talked about much, but one of THE biggest dangers isn't birth defects or inedible fish - it's a mass die-off of plankton and algae. The sea's responsible for well over 3/4s of all our greenhouse gas capturing and photosynthesis. We could technically survive without the rainforests - we can't survive without the Pacific full of green. Combined with already-climbing sea temperatures, an increase in radiation could theoretically lead to a 50%+ drop in amount of weeds and plankton in the Pacific, which would cripple oxygen production to below the amount we need to survive. Odds are fairly low (different types of algae and bacteria seem to be taking over with no ill effects....yet), but if it does start happening, we'll have no way at all of stopping it or slowing it down. This could very quickly lead to "kill off enough people so the rest can survive or all suffocate together" - aka, some sort of post-nuclear scifi movie setting thing. In theatres, summer 201....errr.....yeah.

Most likely, though, is this won't happen, and it'll mostly effect wildlife and people in and around Japan.
 
I thought the protocol for a reactor heating up out of control was to bury it. Is that not an option? It seems better than simply irradiating more and more water while making no real progress.
 
Most reactors are designed so when the core melts down it drops into an area where the reaction is dampened by control rods. It's still putting out heat, though, so even if the reaction is slowed it's not stopped, and you still have to cool it actively until you can go in and take out, or separate, or add more control material until the reaction is letting off so little heat that burying it won't result in an explosion.

The safety area that the reactor drops into doesn't have enough control material to fully stop the reaction, only to slow it down.

I don't know exactly what went wrong here, but early articles suggested that the reactor melted down past the safety area and ended up flowing partially into the secondary containment vessel. I don't know if that's the case or not - I'm sure there's more information out there - but if this is what happened, then it explains the strange cooling protocol they're following since the secondary vessel wasn't built for cooling, doesn't have the control rods, and so they're probably just flooding it with water and sucking it back out continuously. Until they can get robots in there and remove or separate the material, which may still be molten, they're going to be cooling it for years and possible decades before it's cool enough to deal with. Note that the robots must not only be waterproof, but must operate under high temperatures and pressures.

Of course, this is again all off the top of my head. I'm adding lots of disclaimers because I haven't thoroughly researched it since this time last year.
 
And for the moment, robots still aren't an option - they can't get anything to work in the conditions, not even robots designed for space travel (which is the other highest-radiation area to work in).

Still, any somewhat modern nuclear power plant should have a triple loop cooling system - I can understand them needing more direct cooling methods and everything, but you'd expect them to have been able to rig something to limit/minimize outside irradiation.
 
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Yeah, I'm really scratching my head here. It took us 8 years to go from announcement to landing a human on the moon. You'd think that we could cool and contain a relatively small pool of radioactive material on earth in 2 years.

Buy up the surrounding land, build 10 huge cooling towers, build a new building to house the pumps and heat exchangers, and start cooling the containment building aggressively. The site is already a disaster area. I hope they're not trying to recover it.

But 2 years is more than enough time to build a superhuge cooling plant that wouldn't need to store radioactive water. Yes, as the radioactive loop became more radioactive they'd have to remove some for storage and add more in to dilute, but the storage requirements should be lower.

There are a number of materials that are uranium solvents - they'd cause the uranium to go into the solution. I wonder if they could add some of those to the cooling water, then use reverse osmosis to filter them out of the loop and remove the reactive material from the core slowly as they're cooling it...
 
Buy up the surrounding land, build 10 huge cooling towers, build a new building to house the pumps and heat exchangers, and start cooling the containment building aggressively. The site is already a disaster area. I hope they're not trying to recover it.
They recovered Hiroshima and Nagasaki. They WILL recover this area in time, if only because it's a very Japanese thing to do. In the mean time though, they really need to just level the area and build cooling towers and containment vessels.
 
Sounds like the long term plan is to build a recovery plant on site to do the clean up. Hopefully the government takes over soon and gets someone capable in charge of the containment and clean up. These guys sound like they're way over their head in this.

Another article on it.
Massive amounts of radioactive fluids are accumulating at the plant as Tepco floods reactor cores via an improvised system to keep melted uranium fuel rods cool and stable.
The water in the cooling system then flows into basements and trenches that have been leaking since the disaster.
Highly contaminated excess water is pumped out and stored in steel tanks on elevated ground away from the reactors. About 400 metric tons of radioactive water a day has been stored at Fukushima.
In order to keep up with the pace of the flow, Tepco has mostly relied on tanks bolted together with plastic sealing around the joints. Those tanks are less robust - but quicker to assemble - than the welded tanks it has started installing.
The latest leak came from the more fragile tank, which Tepco plans to carry on using, although it is looking at ways to improve their strength, said Tepco official Masayuki Ono.
A puddle that formed near the leaking tank is emitting a radiation dose of 100 millisieverts an hour about 50 cm above the water surface, Ono told reporters at a news briefing
 
In order to stem the flow of leaks from the plant, Japan is going to freeze the ground around the plant, forming an underground ice wall that should at least contain leaks, and prevent groundwater from drawing radioactive waste to the ocean.

The wall will only extend around the plant itself, though, not around the storage area where leaks are another big problem - but are all above ground leaks so can be more easily identified and solved in an ongoing basis.

http://www.bbc.co.uk/news/world-asia-23940214
 
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