Finally, a decade late, the radioactivity problem at Fukushima is going to be solved in the right manner – dump it all into the ocean.
Japan’s government has reportedly decided to release more than 1m tonnes of contaminated water from the Fukushima Daiichi nuclear power plant into the sea, setting it on a collision course with local fishermen who say the move will destroy their industry.
Media reports said work to release the water, which is being stored in more than 1,000 tanks, would begin in 2022 at the earliest and would take decades to complete.
An official decision could come by the end of the month, the Kyodo news agency said, ending years of debate over what to do with the water, with other options including evaporation or the construction of more storage tanks at other sites.
Evaporation doesn’t work as a solution. Or rather, is no different from ocean dumping. The problem is tritium. Something already extant in seawater to a certain degree. And it isn’t there as something separate, “tritium”. It’s just heavy hydrogen (the normal one electron, one proton, but here with two instead of no neutrons) and it’s already bound with oxygen as water. That is, we’ve got some amount of heavy water mixed in with normal water. You can evaporate off the water, course you can. And that heavy water will evaporate too – at a very slightly different rate from the normal but still. That is, the evaporation idea dumps it all into the oceans anyway just after it has been a cloud that rained instead of before.
As to why this is the solution something in the sticky back plastic style from earlier:
I’m reading with mounting incredulity the increasingly frenzied reports about the radiation problems at the site of the crippled reactors at Fukushima. The idea seems to be gathering speed that there is some major problem at the site, one that’s going to have regional or even global implications for health and the environment. I’m afraid this simply isn’t true. We do have a very expensive problem and there are also highly local problems at the plant. But in the larger scheme of things the dangers are somewhere between vanishingly trivial and non-existent. Indeed, an entirely reasonable and sensible solution to the radioactive water at the plant would be to simply dump it all into the ocean.
As is reported in the New Scientist:
The crisis reopened questions about how to deal with the flood of radioactive water accumulating at Fukushima. There is a radical option: to filter out as much radioactive material as possible, dilute what’s left, and dump it in the Pacific.
And this isn’t the suggestion of some crank:
Other parts of Fukushima are certainly leaking. From samples of seawater, Jota Kanda of Tokyo University of Marine Science and Technology estimated last year that about 0.3 terabecquerels (TBq) of radioactive material are leaking into the sea each month.
Ken Buesseler of the Woods Hole Oceanographic Institution in Massachusetts says the Kanda estimate is probably the best he is aware of, and closely matches figures released on 21 August by Tepco, of 0.1 to 0.6 TBq per month for caesium-137 and 0.1 to 0.3 for strontium.
He points out that the north Pacific contains an estimated 100,000 TBq of caesium-137 from H-bomb testing in the 1960s, so the fallout from Fukushima is adding only a fraction of that.
That is, that the current manmade radioactivity of the Pacific is rising by 0.001% per month. This is the addition over and above the natural radioactivity of the same ocean of course.
Buesseler says that during his own sampling survey in waters 30 to 600 kilometres from Fukushima in June 2011, three months after the meltdown, the highest levels he found were 3 Bq of caesium-137 per litre of seawater. By comparison, the natural weathering of rocks results in about 10 Bq of radioactive potassium-40 making it into each litre of seawater.
And 4 Bq is under what we consider the safe level for drinking water. So we’re not even going to manage to get above what we already think is OK to come from our taps. And they conclude:
The ocean would be the safest place for the waste water, says Geraldine Thomas, who runs the Chernobyl Tissue Bank at Imperial College London. “But to make that politically acceptable they have to talk to the local population. They have to make people understand that low levels of radiation don’t matter because we’re all exposed to it all the time.”
In other words, it is more of a communication problem than a public health problem. “None of this is going to do anything health wise,” she says. “Fukushima is nothing compared to Chernobyl.”
And Chernobyl killed very few people: absolutely certainly fewer than fossil fuels kill each year by orders of magnitude.
Let’s just walk through the three problems there are at Fukushima. The first and most obvious is that we’ve got broken reactors. Those cores melted down to some or greater degree. They’re still warm, both in temperature and radiologically. But they’ve not gone walkabout, they’re not sinking into the earth, they are static and very expensive lumps of scrap metal. If we stopped cooling them they might warm up again but they’re simply not going to explode not are they going to “go critical”. They’re most certainly nasty things that would kill anyone who decided to go stand next to them if they were uncovered but that’s not going to happen either.
At which point it’s worth having a look at this XKCD explainer. One of the reasons they keep pouring water over those lumps of metal is precisely because water is so good at absorbing the radiation.
At some point in the future those melted cores will be extracted, put back into water for a few decades until they’ve finally cooled down in a radiological sense and then they’ll go off to wherever it is that someone finally decides long term nuclear waste should go.
The second problem is the one about ground water from above the site feeding through it and then into the ocean. This is the radiation release I wrote about here when I compared the hourly release of radiation to that of the hourly consumption of bananas. It’s actually about half the global and hourly consumption of bananas in fact. Another way of looking at it is as John Binder put it in the comments to that post:
I think another good comparison would be to compare what has gone into the ocean to what was already in the ocean.
The oceans have Uranium in them. In the pacific ocean the radiation from Uranium is 22 EBq or 22,000,000 trillion becquerels.
The oceans have Potassium 40 in them. In the pacific ocean the radiation from Potassium 40 is 7,400 EBq or 7,400,000,000 trillion becquerels.
The oceans have Carbon 14 in them. In the pacific ocean the radiation from Carbon 14 is 3 EBq or 3,000,000 trillion becquerels.
The oceans have Rubidium 87 in them. In the pacific ocean the radiation from Rubidium 87 is 700 EBq or 700,000,000 trillion becquerels.
The oceans have Tritium in them. In the pacific ocean the radiation from Tritium is 370 PBq or 370,000 trillion becquerels.
So we have…
Uranium 22,000,000 trillion becquerels
Potassium 40 7,400,000,000 trillion becquerels
Carbon 14 3,000,000 trillion becquerels
Rubidium 87 700,000,000 trillion becquerels
Tritium 370,000 trillion becquerels
Total 8,125,370,000 trillion becquerels
So we have 8,125,370,000 trillion becquerels of radiation in the pacific ocean and the antis don’t seem to care, but when the fifth most powerful earthquake ever recorded results in 20 trillion becquerels of radiation being released into the oceans over two years we’re supposed to all accept that it’s a horrible disaster.
Just to thank Mr. Binder for that there. I always get lost in the zeros when I try to do those comparisons. But the takeaway point is that there’s just not that much radiation entering the ocean compared to what is already there. If the extra amount were going to do any harm then we should all be dead from what is already there. Given that we’re not then the extra amount isn’t going to cause problems.
But even so the work is going on to try and stop this leak into the ocean. Despite it not actually mattering it is still being done. This is the idea that they will freeze the earth uphill from the reactor. Thus that groundwater will not flow through the contaminated areas but around them and not become contaminated. Expensive, doesn’t really need doing but it is going to be done.
And then there’s our third problem which is what is all over the news today.
Readings just above the ground near a set of tanks at the plant showed radiation as high as 2,200 millisieverts (mSv), the Nuclear Regulation Authority (NRA) said on Wednesday. The previous high in areas holding the tanks was the 1,800 mSv recorded on Saturday.
Both levels would be enough to kill an unprotected person within hours. The NRA has said the recently discovered hotspots are highly concentrated and easily shielded.
Yes that’s bad and no it shouldn’t have happened. But there’s also a certain amount of hysteria about this:
“The radiation concentration was found in the H3 area of storage tanks, which are the same type of tanks that have leaked in the past,” a spokesperson for Tokyo Electric Power Co. told The Daily Telegraph.
“The reading of 2,200 millisieverts was found around 5 cm from the tank, but it had fallen to 40 millisieverts per hour 50 cm from the tank,” the spokesman said.
So we seem to have an area of ground that is some two feet across that is heavily contaminated. By the way, this is Beta radiation, meaning a stout paid of boots will protect you from it.
What’s happening here is that some of those water tanks are leaking. One or more, we’re not quite sure. This is not that ground water in problem two: this is rather water that has been used to cool the reactor cores and the used fuel pits. This is pumped in to cool them and them pumped out again. Stored in those tanks that you can see in all the photos of the plant. This is not, contrary to some reports, an ever increasing amount of water that must must then be stored forever. This is water that has been contaminated with radioactive particles: and we can extract the radioactive particles. As indeed they have been doing all along. There are a number of methods they can use to do this, from simply boiling the water off to filtration to ion exchange extraction and so on. From what I’ve seen the equipment is using a combination of these techniques to maximise the radionucleide extraction.
They have encountered problems with this work: from what I understand it’s because they’ve got salt, or seawater, mixed in there. You might remember that right back at the beginning they flooded the reactors with salt water to cool them after the fresh water pumps had failed. It’s the salt in that salt water that is clogging up the extraction of the radionucleides. The equipment designed to extract those radioactive particles was designed to be used on contaminated fresh water. The other salts in sea water are overwhelming the capacity of the equipment to purify the water. This is indeed a problem now: but it’s not a long term one. The purification will simply take longer that is all.
Once those radionucleides have been processed out they’ll be stored in the same place that the old fuel rods will go to and will be secure for the centuries necessary until they decay into irrelevance. The water will just be water again.
So there are indeed problems at Fukushima. But they’re just not the ones that everyone seems to be getting so hysterical about. We’ve some engineering problems, most certainly. Building that frozen wall to stop the groundwater flowing through the site. Purifying that water that has been used for the cooling, that’s an engineering problem too. They’re both expensive and entirely solvable problems.
The real problem is that we’re having to do those two very expensive things. Two things that we almost certainly shouldn’t be bothering to do at all. As both those who have studied Chernobyl and Woods Hole, the ocean experts, say, the simple and logical solution to both the ground and cooling water problems is to dump the lot into the Pacific Ocean. It’ll dilute down to be some tiny fractional addition to the radioactivity that’s already there and that’s all it will do.
No, I do not recommend that we dump the cores nor the fuel rods into the ocean. This despite the fact that many people have already done that before:
During the 48 year history of sea disposal, 14 countries have used more than 80
sites to dispose of approximately 85 PBq (2.3 MCi5) of radioactive waste
Note the P in front of the Bq there. Fukushima, from the ground water, is some 20 TBq of tritium over the past two years. That is also 0.02 PBq. It’s not even making a noticeable difference to the amount of radioactivity that humans have dumped as waste into the oceans let alone to the amount of that plus natural radiation plus that from the atmospheric bomb tests.
Some 43.3% of the activity in the
disposed radioactive waste is associated with the dumping of reactors with spent nuclear fuel by
the former Soviet Union in the Kara Sea.
Yes, people really did used to dump whole old reactors into the sea. And no, I don’t think that’s a good idea at all.
But that radioactive water at Fukushima? The experts are telling us that we might as well just tip it into the Pacific. It’s not going to make any difference to anything if we do but it will be a great deal cheaper.