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I am not reflexively anti-nuclear. However, I have never heard a satisfactory answer to the simple question: "How do we store nuclear waste safely?"



We burn it! That is, nuclear burn it, not chemically. And what can't be burned can be bombarded with neutrons into radiological inertia. And what can't be neutralized in that sense can be molten into a ceramic, more specifically, a glass, and stored underground. Which is of course where it came from, when you think of it. Seriously, nuclear waste storage is not a problem. This page gives an excellent eplanation: http://www.phyast.pitt.edu/~blc/book/chapter11.html

Nuclear energy has lots of problems, and I personally think this article is not worth this place on HN, but waste is not really one of them, especially compared to the scale of chemical wastes from fossil fuels.


Do you burn it? Why is it than that every reactor I know of, in US, WE, Japan, stores tones of extremely dangerous waste on site?


Since regulations don't allow any other option e.g. the US doesn't allow reprocessing.

Also: what better place to temporarily store nuclear waste in the exact same place where it is produced where safety and security measures are already in place?


I will try without the condescending tone of the other commentor: Why does this not increase the possible damage a meltdown would cause?

Or does it increase the possible damage, but the security is high enough that the expected damage is lower than storing it elsewhere?


First, a containment structure[1] is a key feature in any reactor[2]. These are massively over-engineered specifically to contain even unlikely problems. We learned that this was important after the SL-1 accident[3]. As you suggest, this is a feature designed to fail safely - the containment should keep the rest of us outside the building safe, and doesn't say anything about what happens to the stuff in side.

> meltdown

This term is thrown around a lot, and while solid fuel melting in a traditional reactor is a serious event, a lot of people seem to think that "meltdown" is some kind of terrible or damaging event. The reason people in the nuclear industry panic over a possible meltdown has little to do with safety; up until that point you could - in theory - still reasonably believe that the reactor could be fixed and (eventually) restarted. After a meltdown, you have to assume the core is trashed and is now a financial liability instead of your main source of revenue.

Meltdowns are a terrible event financially. The actual melting of the fuel involves the passive-safety, which are usually designed to drain that fuel into (multiple) areas where it can cool down without criticality risk.

All of this is still discussing very old features. This is like worrying about today's computers because vacuum tubes are fragile and need to be replaced when they burn out. Modern reactor design is very different, because we learned form the problems that happened in the original designs, just like any other technology. Unfortunately, propaganda based on radiophobia has been a serious roadblock. Ironically, this means we're stuck using older designs that should have been replaced decades ago with modern reactors that emphasis passive safety.

If you're interested in a brief overview of these problems (and why some of us believe thorium breeder reactors are the answer for many of these problems), I recommend watching "Th"[4]. Just remember it's an overview, and they skip over some of the details to keep it short.

[1] https://en.wikipedia.org/wiki/Containment_building

[2] a feature that was missing at Chernobyl, which is one of many reasons that accident affected such a large area

[3] https://www.youtube.com/watch?v=qOt7xDKxmCM

[4] http://thoriumremix.com/th/


Yeah, right next to a reactor, so that a meltdown causes 10x more damage.


I think brrt is talking about "burning" nuclear waste in a molten-salt reactor or similar. Some types of existing fission reactors can only utilize a small percentage of the uranium in their fuel rods, after which the rods must be removed. The rods must then be stored, and possibly reprocessed afterwards.

MSR and other fission reactor types can utilize 100% of the fissionable material put into them, so this sort of leftover "waste" is not such a problem.


Yeah, so there is a solution to nuclear waste - in fantasy land.


It's called a breeder reactor, they are quite common in some places (but not in the US). I guess those places are "fantasy land"? Pretty cool since I can visit them.


Because "just burning it" requires engineering and implementing a different nuclear technology with its own issues.

Nuke advocates always practice magical thinking. Wave away safety concerns. Write off intractable waste disposal issues as "just bury it". The reality is that nuclear as it stands today is a relic of the Cold War. Solar, wind and gas are the future.


Because burning it involves superheated, radioactive phosphoric acid.


What are you talking about? No it doesn't.


The designs I have seen dissolve the spent nuclear fuel in phosphoric acid and then operate with liquid fuel. ( Perhaps there are proposals that do not operate like that, but I think you want to homogenize the fuel as much as possible which means some kind of liquid fuel.)


How do you superheat phosphoric acid? Wouldn't it dissociate?

It's not used for an active reactor, but rather to dissolve cold fuel and extract more usable uranium.

Liquid fuel reactors don't use phosphoric acid, they use uranium tetrafluoride (a salt) or water.


No, you want to burn all the short lived isotopes, not just Uranium. So the designs I am talking about use spend fuel dissolved in acid as a fuel. There is also spent fuel recycling, where you take Uranium and Plutonium out of spent fuel and manufacture MOX fuel, but that is an entirely different process.


specifically, NOT a glass: https://en.wikipedia.org/wiki/Synroc


And still radioactive.


Dumping it to the ocean is pretty safe. Seriously: https://en.wikipedia.org/wiki/Ocean_disposal_of_radioactive_...

However, since people don't easily believe water's a very effective radiation shielding (even if there's an xkcd of it https://what-if.xkcd.com/29/) and that heavier than water metals kind of tend to stay put at the bottom of the ocean, other means of disposal might be more realistic. Recycling in breeder reactors, digging huge holes to the ground, buildings which last longer than pyramids etc.

Of course, how one defines "safely" is tricky. Perfect safety is impossible, of course. One can't guarantee that our hole will stand to the heat death of the universe - but just ensuring that the disposal will cause less harm to earth and its living beings than any other energy production method is fairly easy to do. Even windmills kill some people, animals and fauna during normal operation, so if we set "less murderous than windmills" as an acceptable safety standard, we could settle for the ocean disposal, for example.


Actually, Britain did that. They dumped most of their waste in the channel.

Result, 20 years later: The waste did not dilute, the radiation in the channel is damaging the local animals.


The channel's a really dumb place to dump waste. There's a massive difference between a life-rich continental shelf with a complex ecosystem, and the barren abyssal seafloors five miles down. Put the waste there and it will just stay there for millennia.


This doesn't seem like a very straightforward process. If it were, I'm sure we'd get rid of all sorts of nasty shit that way. Is every component of "the safe nuclear power we'll have in future" yet to be developed?


Pretty much. Hitachi is currently selling their IFR design "on-the-shelf" by name S-Prism. Russians are operating and selling their BN-600 and BN-1200's.

It's not like things are completely problem free, but that's kind of unreasonable expectation for any industrial or commercial project.

E.g. advertising breeders as a solution for the nuclear waste problem is a bit tricky, since we already have centuries worth of waste to dispose of, plants will only be operated for some decades etc. We would need to increase humanity's electric consumption to tenfold or more to justify enough breeders to dispose all current nuclear waste in reasonable time.


The barren abyssal seafloors are life rich with a complex ecosystem for what we know of it and in matters of ocean we know pretty much nothing.

Also the cost to get there is quite high and there's no reason to think radioactivity would stay there.


It's not supposed to dilute. It should stay put and not spread around.

Most human activities tend to displace natural ecosystems. Waste dumps (nor windmills) are no exception. The question is, is the damage lesser than greater than in proposed alternatives?

Though I do not understand why did they choose to dump the waste to the channel? If I would dispose the waste by sinking, I would use a kilometers deep trench to minimize risks for reacquirement and environmental damage. Do they plan to dig up the waste sometime in the future?


Well, they did it because it was easy. And cheap.

If you want safe nuclear power, including demolishing the reactors safely, safely getting rid of all the materials, nine nines safety, etc, then it won’t be profitable.

If you want for-profit nuclear power, then either the government has to subsidize it, or it has to be unsafe.

Usually, it’s both unsafe (companies save money everywhere, including stuff like not securing the generator cough Fukushima cough) and barely profitable.


Depending on the definition of "safe". Digging a long hole to the ground, towing an old to-be-demolished barge on top of Mariana's trench etc. is not that expensive.

The hard part right now is deciding on suitable ground for the tombs. Doing seismic measurements, analyzing the rock formations and especially forming the policies for burial (e.g. do we reserve the option to dig the stuff back up for use in breeders?) can take decades, but it's hardly an expensive part of the process.

The disposal isn't really an acute problem that needs to be solved today. It's not that dangerous to store the junk at warehouses while we use hundred years if necessary to research best viable options.

Nuclear power is expensive, but only if you compare it to burning hydrocarbons and hydroelectric power generation. It's still decades ahead of photovoltaic and wind turbines.


Well...

> but it's hardly an expensive part of the process.

https://en.wikipedia.org/wiki/Asse_II_mine

> Das Gesetz zur Beschleunigung der Rückholung radioaktiver Abfälle und der Stilllegung der Schachtanlage Asse II („Lex Asse“) wurde am 28. Februar 2013 durch den Bundestag beschlossen.[70] Die Kosten werden auf vier bis sechs Milliarden Euro geschätzt.[71] Sie sollen nicht durch die Betreiber, sondern durch den Bund getragen werden.

Translation:

> The "Nuclear Waste Retrieval Speed Up and Asse II mine closing law" was passed on February 28, 2013. The costs are expected to be between four and six billion Euro. They will be paid not by the owner, but by the federal government.

Germany built one. Turns out it wasn’t that safe. Now we have to dig up all the waste again, and put it back underground into a different mine. And this mine was our only hope, actually, because it was the only semi-stable unused salt mine left in Germany.

Now the government passed a tax "Brennelementsteuer" (Nuclear Fuel Tax) that means the owners of nuclear power plants have to pay parts, approx up to 20% of the costs for demolishing the plants, and still 0% of getting rid of the waste, this money will be gotten as a tax for using nuclear fuel.

And, with this tax, nuclear energy is now, even despite getting similar subsidies as renewables, more expensive than wind. Several large energy companies already sold their nuclear plants and switched over to wind; even the few plants in Germany that were still running after Fukushima are now not profitable anymore.


Bury it deep enough?

Somehow everybody freaks out about nuclear waste and says stuff like "But after 20,000 years it will still retain half of its radiation!"

Well, our industrial waste also contain mercury and other heavy metals. We usually just bury them. Somehow nobody freaks out and says "But after 20,000 years it will still retain ALL of its toxicity!"

I can't fathom why.


And what they also don't appreciate is that nuclear material with a 20,000 year half-life has, by definition, very very low radioactivity.

It's like any other fuel -- the faster it burns, the shorter it lives. And vice versa.


Yes, very much this.

"Long half-life" = "not very radioactive" by definition.

"Half-life of infinity" must sound really scary to these people, but that's the same as saying that it's not radiactive at all.


Very simple - a few tones of Uranium or Plutonium, dispersed in air or water can kill the population of a continent.


Very simply, you're wrong. Badly wrong.

http://spectrum.ieee.org/energy/nuclear/nuclear-fuel-from-th...

The ocean contains 4.5 billion tonnes of uranium already. 4.5. BILLION. TONNES. Dispersed in water.

I haven't noticed any continents dying off because of this, have you?


But it's well-known that dying continents leave the pack and slink off into the mantle to die alone, so you wouldn't necessarily have seen it.


Which is, ironically, only possible because of radioactive heat generated by the Earth.

Without radioactivity, there would be no continent to die in the first place.


Have you heard about that discovery called radioactivity? Different isotopes? Ocean water >>> fresh water?


Sure, I've heard of all of those things. What do they have to do with your claim?

You claimed that "a few tons" of uranium or plutonium, dispersed, could "kill the population of a continent".

Sorry, that's nonsense.

Have you heard of arithmetic? Try doing some. Start by figuring out how many tonnes of air there are over North America, then figure out what concentration of plutonium would result from dispersing a "few tonnes" in that volume of air.

Hint: Not nearly enough to kill everyone on the continent. Likely not even enough to make the cancer rate go up by any measurable amount.

Here, I'll even help you out a little. North America covers about 25 million square kilometers, or 25 trillion square meters, and there are roughly 10,000 kg of air over every square meter at standard air pressure, so we're looking at about 2.5x10^17 kg of air, or 2.5x10^14 metric tonnes of air. Plug in whatever number you like for a "few" tonnes of radioactive material and figure out what concentration will result.


Where do you get this stuff, anyway? Wherever it was, I would recommend not placing any credibility on that source in the future.

In fact, if you ground up the Fukushima reactor whole, to a fine powder, and dispersed it over the entire ocean, it wouldn't make one bit of significant difference with respect to the concentration of radionuclides.

Heck, the Soviets used to dump their scrapped sub reactors into the Arctic Ocean whole. There are dozens of them up there, probably (I don't have a hard number on this). It hasn't killed any oceans or continents yet.

Would I go scuba diving near one of the dump sites? Hell no! Am I going to lose any sleep over the prospect of them killing the entire ocean? Likewise hell, no!


Which is why you bury it.


Waste stays very radioactive for millions of years. Even after that remains extremely toxic. Earthquakes, volcanoes, diggers can trigger an apocalypse.


Everyone brushes over that, the billions of dollars to build a plant, and the ~10 year construction time. Any nuclear power plant that has construction started today won't be cost competitive with renewables when it comes online.

It would be like building a new coal plant in the US today. You simply can't compete with wind, solar, and natural gas (which is still superior to coal, and I don't mind it being a stranded asset for whomever invested in it as solar and wind ramp up).


Makes you wonder how they built the first generation of reactors in a few years time for a couple of million usd. http://thorconpower.com/costing/should-cost-versus-did-cost


At least in UK the costs got offset to clear up. http://www.bbc.co.uk/news/uk-england-cumbria-21298117


How do wind and solar provide a solid baseline power. And China builds nuclear plants a lot faster and cheaper than we do, and no known accidents. Maybe we can learn something from them. Plus the whole 90% of a nuclear plant's cost is servicing the debt. Once completed the operational costs are a rounding error.


> How do wind and solar provide a solid baseline power.

Properly built and managed distribution networks, along with utility scale battery storage.

> And China builds nuclear plants a lot faster and cheaper than we do, and no known accidents.

Yet. China still gets more power from wind than nuclear, and they're building out wind generation capacity far faster than nuclear: http://www.earth-policy.org/data_highlights/2015/highlights5...

> Maybe we can learn something from them.

Indeed. When you're an authoritarian regime, you can operate more fluidly "at scale" (fuck you, I do what I want).

> Plus the whole 90% of a nuclear plant's cost is servicing the debt.

And yet, someone has to pony up those billions of dollars. A kickstarter perhaps?

> Once completed the operational costs are a rounding error.

And when you fail hard, it costs billions of dollars to cleanup: http://www.psr.org/environment-and-health/environmental-heal...

I'll take solar and wind, thanks.


>And when you fail hard, it costs billions of dollars to cleanup: http://www.psr.org/environment-and-health/environmental-heal....

Using Fukushima as an argument against nuclear is such a silly thing to do, and the decades long freeze on any sort of real progress in meaningfully upgraded or new commercial reactors makes this sort of thing a self fulfilling prophecy.

How many industries have catastrophic failures? How many people have been killed by hydro-electric dams? How much financial damage? https://en.wikipedia.org/wiki/Banqiao_Dam

We've created a climate where a completely viable power option that is better than what we have now has had innovation massively stifled due to politics and fearmongering, which has in turn made it more difficult for nuclear plants to be a safe option, which then allows for even more politics and fear mongering.

Fukushima? Yes, it was a catastrophic failure. But it was hit by a 9.0 earthquake and then a tsunami. It was scheduled to be shut down two weeks from the earthquake. It was a 4 decade old plant that was being shut down due to it's age hit by some of the worst possible natural disasters, and even then some better design choices, such as a higher seawall, or not storing the backup generators underground would have prevented it. The condenser units also hadn't been inspected or had maintenance performed on them since basically the reactor's opening. Everything that happened with Fukushima could have been prevented even with it's old technology despite being batter with one of the worst natural disasters in modern history. And this is with 4 decade old technology. With a more favorable political climate, how many advances in safety and efficiency could have been made over those decades?


It's not just about trusting the technology, it's about trusting the human processes that govern and maintain that technology. You say that Fukushima could have been prevented, and yet -- it wasn't prevented.

Humans are greedy, generally corrupt, and bad at maintenance when things are going well. To really trust nuclear, we need better humans, since the accidents can be so catastrophic.


utility scale battery storage seems highly improbable to ever be cheaper than nuclear. If we figure a pretty generous 50% loss of energy, that means you need twice as much power production to service the nights and windless days.


Lithium batteries are in no way going to be so inefficient as to have a 50% loss of energy. They're already cost competitive in Hawaii for utility scale storage:

http://www.utilitydive.com/news/hawaii-co-op-solarcity-ink-d...


What happens when when 52MWh (~216 tons of lithium iron batteries) goes into thermal runaway?


You don't have have to put all of the 52MWh side-by-side.


Over capacity and in the US Hydro can easily cover most issues. Other areas may use peaking power plants or grid storage just like today.

PS: If you build more wind than you need it does get slightly more expensive, but the wasted peaks are a fairly low percentage of energy generation so there not that important. ie. If you build 5% more wind than you need the cost only increases by 5% but you need to time shift far less power. Considering how much cheaper wind is than Nuclear you can have a lot of extra capacity factor.


> You simply can't compete with ... natural gas

Not necessarily, not if you include the environmental costs. Natural gas may be considered "superior", if you don't mind the damaging effects of hydraulic fracturing over the environment. Water contamination is no small deal.


I don't disagree with this, but the wells are sunk and producing. We should definitely not continue with hydraulic fracturing; in the interim, existing natural gas supplies can make up the reduction from nuclear's decline until solar and wind overtake both.


The question is not about about "safely", the question is about "in a safer way than the alternatives".

So, let's look at how we can safely store coal/oil waste. We can't, it goes straight in the air, or in the sea. So in this sense, I'd argue even simply dumping our nuclear waste in the Mariana Trench would be safer.



You don't just store it, you repeatedly reprocess and reuse it to extract all of the valuable highly energetic material. The remainder can be stored in geologically stable underground facilities, where it is no more environmentally impactful than uranium ore was prior to being mined.


Being very familiar with nuclear waste, I can say that, from a technical pov, it's a solved problem: just put it deep enough to comply with whatever safety level is required. The problem with nuclear waste is political not technical and not economical.

Reprocessing or transmutation are alternatives to handle nuclear waste but they have in common that they're more expensive and even less acceptable to society.


By not hiding it away, but using warehouses that are actively staffed just like the plant that made the waste. Of course these facilities should be secure installations. But the root of the problem is not wanted to actively take ownership responsibility for the waste. I imagine every major city having its secure storage installation.

Consider the scale of waste generated as well. All the waste used to power a life of electrical usage creates was the size of a pea.


> All the waste used to power a life of electrical usage creates was the size of a pea.

Source on this?

Best I could find shows that 3 cubic meters of waste is generated per year for a "typical 1000 MWe light water reactor" after reprocessing and all (which isn't always done). [1]

With 99 plants in the US (not counting the plants with multiple reactors) that leads to 297m^3 of waste.

With a population of 318 million, that's about 9.3x10-7, or approximately 4-5 peas per year or 367 peas over the course of a lifetime.

[1] http://www.world-nuclear.org/info/Nuclear-Fuel-Cycle/Nuclear...

EDIT: Forgot that we only get about 20% of our power from nuclear energy, so it's actually closer to 1835 peas.


The complex "social" side of the problem (for example, the vast amount of waste produced by the manufacture of nuclear warheads during the Cold War) means that it is not easily solved. There's a documentary film coming out about this by Peter Galison and Rob Moss. http://containmentmovie.com/


Even ignoring modern reactor designs that can use waste isotopes as fuel, we had a perfect storage solution in Nevada... until Harry Reid sabotaged it, costing taxpayers hundreds of millions of dollars.


Thorium waste has a half-life at ~100 years. We can certainly build containers to safely store that waste until it is no longer harmful.


a) How is "put it in Yucca Mountain" not satisfactory? b) Do you demand similar levels of safe storage for all of the hazardous materials, many of which are far more dangerous than nuclear waste, produced by other industries, including those involved in renewables technologies?




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