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Comment by apsec112 | Hacker News Reader

Everyone is so terrified of nuclear waste, because it lasts "hundreds of years", which seems like a really long time. Why is almost no one terrified of chemical waste, which lasts literally forever, or at least until after the Sun burns out?

Global production last year:

Arsenic (arsenic trioxide): 44,000 metric tons

Mercury: 1,900 metric tons

Selenium: ~3,000 metric tons

Beryllium: 400 metric tons

Lead: 4,000,000 metric tons

Cadmium: 23,000 metric tons

All of this stuff will last literally forever, and is more-or-less impossible to destroy. This doesn't include all the fun chemicals (eg. cyanide) which are possible to destroy, but get dumped into the environment before disposal and so are floating around anyway.

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Chemical waste is a problem but it is not nearly as deadly or difficult to handle as nuclear waste.

Just one obvious example -- you can put lead into metal blocks and store it virtually anywhere (well away from drinking water).

Nuclear waste irradiates stuff around it, generates heat, and causes everything you put it in to rust and deteriorate very quickly. Some nuclear waste generates so much heat that it has to be continually actively cooled so that it does not set itself on fire and spew clouds of radioactive gases.

If there was a warehouse full of blocks of lead in fukushima, the tsunami would not cause much of a disaster. Nothing worth mentioning on TV. But instead there was nuclear waste storage, which had to be actively cooled. So when the tsunami knocked out the cooling systems, it caught on fire and there were the clouds of radioactive gasses.

The radioactivity and maintenance requirements are certainly problems but the extreme regulation in the nuclear industry compared to other industries may drastically mitigate their long term impact, especially compared to the many chemicals we use that bioaccumulate in the food chain. With the amount of mercury, lead, cadmium, and other heavy metals that we routinely dump into the environment, we really don't know what the long term effects will be as they make their way in ever greater concentrations into animals across the world.

Already there is mounting evidence that these chemicals are having an extreme effect on the top layer of ocean life (which is estimated to produce the majority of our oxygen) and if we continue on the path of indiscriminately dumping toxic waste the resulting effects could be significantly more dire than if we powered the entire world with fission. Properly regulating nuclear waste from reactors and disposing it might be more practical than regulating all of the other uses of heavy metals and toxic chemicals. If we further manage to develop technologies that can pump waste back into reactors as fuel or to convert them to more unstable isotopes (which decay to stable ones faster than hundreds of years) the entire problem can become much more manageable. Unfortunately we seemed to have written off nuclear almost completely and will never get there.

These are two drastically different industries (power generation vs manufacturing) but the comparison is still worth keeping in mind.

Which of these places would you prefer to visit?

* Fukushima Prefecture, Japan - near the Fukushima Daiichi power plant

* Pripyat, Ukraine - near the Chernobyl power plant

* Bhopal, Madhya Pradesh, India - near the Union Carbide India Limited pesticide plant

* Bullitt County, Kentucky - near the "Valley of the Drums"

You choose lead as your example for chemical waste, but lead is only a moderate risk compared to the nastier chemical pollutants. The real hazards are things like the PCBs (among hundreds of other nasty chemicals) in the 100,000+ leaking drums at the "Valley of the Drums", or the 42 tons of methyl isocyanate sprayed over Bhopal. These incidents have already had significant costs in human lives and ongoing health problems for the local population.

In comparison, Chernobyl killed only handful of people and Fukushima hasn't killed anybody yet. We are still waiting to see the costs of extra cancer cases from these disasters, but it won't be anything close to the damage from the chemical industries or coal power industries.

Having visited the Hanford site in Washington State, it's a pretty epic thing there trying to deal with the waste from WWII.

Actual nuclear waste is a 10,000+ year problem, not hundreds of years. But the 100s of years problem is more about where long-term storage should be (Yucca Mtn. etc.).

When you tour Hanford, what do you see (free tours for US citizens, BTW)? You see many ancient reactors - all disabled now except the preserved first reactor. You see -every single decommissioned nuclear submarine-'s reactor in long lines. And they remind you: based on ice ages, in 15,000 years or so, it won't matter... the entire plateau around Hanford will be under water. So it's going to need to be somewhere else.

Wild stuff.

Then there's what you don't see. Long-lived radionuclides in groundwater, heading for the Columbia River :(

Dumb question- why not launch it into the sun?

Do the (projected) costs of storing it for 10k+ years exceed the costs of leaving Earths orbit?

We're talking about a massive amount of mass. Sending mass to space costs tens of thousands per kilogram. Storing mass costs far less in the short term, and the long term isn't perceived as the problem of the person paying the bill for the short term.

For that matter, with the number of launches required, at least one of them would fail badly enough to spread radioactive material.

Not a dumb question, but as the sibling comment reflects - it has been pondered before, and it is indeed a "dumb solution", unfortunately.

In addition to cost of launching such huge mass, and the risks of catastrophic failure (blowing up mid-launch would probably end up being worse than the chernobyl-distaster -- think a really, really big dirty bomb with areal detonation) -- there's also the risk of missing the sun, and ending up with a man-made comet.

Even if this weren't insanely expensive...

The sun is far away in terms of delta-V. Getting to low-Earth orbit requires something like 9.4 km/s of delta-V. Getting from LEO to the Sun requires another 21.3 km/s of delta-V.

There are probably transfer orbits that could use gravity assist to make this figure lower, but those orbits spend a lot of time looping around planets and generally hanging out in the solar system, which is probably not the best thing to do with our waste.

It's actually cheaper to escape the solar system than to shoot for the Sun - around 18.15 km/s delta-V from ground to escape.

You would be throwing away the next generations fuel. We only use a tiny portion of that available energy from nuclear fuel. This is stupidly wasteful - we should be reprocessing it and putting it back into the reactors.

A lot of the waste that remains should be used in breeder reactors, such as the LFTR. The amount of actual waste left over if we actually use the entire fuel is tiny compared to what we currently call "waste".

Rockets still tend to go "boom" on the launchpad or shortly after launch at an uncomfortably high rate. A rocket carrying tons of radioactive waste that exploded 30 seconds after launch would create an environmental disaster that made Chernobyl look like a coffee spill.

Not really. Plenty of people live in areas with radon producing rocks in the ground, or where altitude causes higher exposures. Long-lived waste emits less radiation than short-lived. If people are fine in Guarapari, they would be fine on top of Hanford in 5,000 years.

I always make this point too. It's very weird. My guess is that when you name a timeframe for the danger, like "a million years," people start thinking about waiting it out. And waiting a million years for toxic waste to be safe sounds really tough! With more mundane sorts of toxic waste, it's not even an option, so people are forced to think about it differently.

Well, a million years is a long time for chemicals to change into other chemicals, too. Do you have citations that show chemicals that take longer to convert into harmless chemicals in environmental conditions than the atoms in radioactive waste take to convert into harmless atoms?

The substances listed in the comment I replied to are stable elements. The timeframe for their eventual decay is speculative. If proton decay is real, then these elements will decay with a half-life related to that. There's a rough lower limit on proton decay from available experimental evidence in the neighborhood of 10^34 years. That would give a half life for these elements of something like 10^32 years. All very rough, but it's something along those lines.

If protons don't decay (proton decay is predicted by some theories but has never been observed), then it's even more speculative. Wikipedia's "timeline of the far future" (a fun article to read for many reasons) gives an estimate of 10^46 to 10^200 years for all atoms in the observable universe to decay through other means. I'll leave converting that to a half life up to the reader.

Incidentally, this means that the popular "launch it into the sun" disposal process actually kicks in automatically, before any appreciable decay occurs. Some billions of years in the future, the sun will expand into a red giant and swallow the Earth, and everything on it. Wikipedia says this happens at 7.59 billion years from now, which is a suspiciously accurate number, but I think for the purposes of this discussion, "billions" is sufficiently precise.

> The substances listed in the comment I replied to are stable elements.

The comment you replied to said "more mundane sorts of toxic waste". That would usually be molecules, i.e. built from multiple atoms, probably multiple elements. And every chemical transformation works both ways, and while the probability for a molecule to fall apart or recombine with other molecules might be low, it will never be zero. So to the best of my understanding there's no such thing as a completely stable molecule, the question is simply how long of a time that you consider. Which leads me back to the question what references you have for (toxic, nonetheless, thus probably somewhat reactive) molecules that have a molecular (not radioactive) half life longer than those for the radioactive decay you compare them to.

To restate my point: molecules may be less stable than the atoms they are made of, and less stable than the radioactive elements you compare them to.

Or even compared to the 8 million tons of plastic dumped into the ocean each year, which will never truly degrade. I understand plutonium has a half life of 25,000 years without anything aiding it.

Who says no one is afraid of these? Furthermore, who says that switching over to nuclear for a large chunk of domestic energy production (which I am not opposed to, mind you) will do anything to lessen the production of any of this chemical waste? I don't know where your numbers come from, but my guess is that they're not mostly produced from burning of fossil fuels. Some certainly is, particularly arsenic and mercury from coal burning, but not a majority. Yellowcake processing is also not a super green process; it's mostly done by leaching big piles of ground up rock with strong acids.

His point was that the fear over waste isn't necessarily a consistent one: people fear nuclear waste more than other types of waste, even though those other forms of waste are a much more significant concern. It's not really a question of which is objectively more dangerous, but which is more likely to affect the general public. The odds of someone stumbling across nuclear waste are incredibly slim; interacting with chemical waste, much more likely.

This is silly. That stuff is simply being refined, it was always there on the planet somewhere. The question is where that stuff goes and how we control its movement. The same is the case for nuclear waste, but if we can spend trillions of dollars on war we can send that stuff to outer space, not very far from that technology being feasible. Space elevators and whatnot. Sooner or later we will have nuclear fusion which will solve the problem of waste altogether.

List of ways of getting rid of nuclear waste:

http://www.world-nuclear.org/information-library/nuclear-fue...

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