How should we get rid of Nuclear Waste?

[makinyashikino]

This is a discussion regarding the disposal of nuclear waste, please feel free to share your opinion on what we should do regarding Reactors and their waste.

In order to solve the impending problem of piling nuclear waste, rather than dump it into a mountain in the desert. We launch it into space, sending it on maybe an escape trajectory or into the sun. Although, placing dangerously radioactive on a large stack of explosives may pose some safety risks...

[ThinkOutsideTheHangar]

It's too expensive to put radioactive waste into a graveyard orbit practically, much less in a solar orbit.....especially with all the budget cuts NASA's been getting lately. And there will be hell to pay without precautions if the rocket exploded in the atmosphere.

[red7paulbrennan]

I am a fan of the Traveling wave reactor.

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

[makinyashikino]

I am a fan of the Traveling wave reactor.

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

I was wondering if scientists could use breeders to change waste into usable uranium, in that case we could launch it when it is waste, to mars or the moon. If we ever do go to colonize these places, we could use the now-enriched uranium to produce power for the base.

[MartGonzo]

There's an interesting documentary about Sweden's approach to nuclear waste but unfortunately the name has slipped my mind.

anyway they are building the worlds biggest underground complex to store it, they are designing it to last 100,000 years.

[Sillychris]

Use it to generate more power, duuhhh.

Decay heat + thermocouples, deep in a mine.

[makinyashikino]

Use it to generate more power, duuhhh.

Decay heat + thermocouples, deep in a mine.

You mean like the ones they had on Voyager and Curiosity? I wouldn't imagine those would produce too much power...

[Sillychris]

You mean like the ones they had on Voyager and Curiosity? I wouldn't imagine those would produce too much power...

Yeah like those except with thousands of tons of waste. They're producing power, anyway, why not harness it?

[cantab]

Just drop it in good solid containers in the bottom of the ocean and stop fretting about it. If it does leak it'll be plenty diluted.

[Ralathon]

I have to agree with Cantab on this one. Dump it in either the ocean or some deep mine far away from groundwater.

Nuclear waste does not lend itself very well as a fuel source, that's why it is waste in the first place. We could do all sorts of fancy tricks to give the stuff a shorter half-life, but seriously, the stuff isn't as horrifyingly dangerous as the media makes it out to be. We don't produce much anyway, so we should just dump it somewhere.

During our history of nuclear energy usage we've produced just 70k metric tons of the stuff. Going by average density this is about 15 Olympic swimming pools of waste during our entire history. We'll probably switch to a fusion based energy system in a century or 2. So fission only has to carry us for a measly 2 centuries. The resulting waste is considerable, but it really is peanuts in terms of volume. Dump it, somewhere safe. We can always dig it back up a few centuries later and use our scarcity free economy to get rid of it completely.

[Captain Sierra]

In order to solve the impending problem of piling nuclear waste, rather than dump it into a mountain in the desert. We launch it into space, sending it on maybe an escape trajectory or into the sun.

Have you tried this lately? Crashing something into the sun is bloody difficult, and a highly overpriced, wasteful, inefficient way to deal with it. It'd be easier to crash it into the moon. At that speed, wouldn't it be evaporated instantly and not contaminate the lunar surface?

[Brotoro]

Open Yucca Mountain. Quit being such babies.

[Nuke]

by burning it as fuel in reactors designed in this century.

stop using reactors that were built when disco was cool!

Edited April 23, 2014 by Nuke

[Elthy]

You say "dump it somewhere safe" but what is safe? It has to last for millions of years and no manmade material can do that, so the surrounding stone has to be very stable, too. Here in Germany they tried that with an old salt mine, but thats not even 50 years ago and now water is leaking in and the barrels corrode, so everything has to be extracted again, which will cost about 10 billion euros. Also its a problem that noone whants to pay for the disposal, so they take the cheapest way, some of our waste was found on russian parking spots...

If you have nearly unlimited money and no local people (and politicans) who can vote against its perhaps the best to burry it realy deep. Several kilometers should be enough when you take the right spot, but sadly thats harder than it sounds...

Edited April 23, 2014 by Elthy

[Seret]

Open Yucca Mountain. Quit being such babies.

Geological repositories do make sense, but aren't without their own problems. Transport is a big issue. Are you suggesting we use the Yucca Mountain site for the whole world's waste, or just that from the US? Who's paying? And how do you get the waste there?

While not particularly challenging technically the practical, political and regulatory issues of centralised storage are vexing. Which is why it's not really happening. There are a couple of small repositories taking waste from a limited number of sources, but nothing large scale or coordinated.

[FREEFALL1984]

Dig a 5 mile deep 6 foot wide borehole in a suitably isolated location, cast the waste into a 6ft concrete pellet then coat the whole thing in an inch of PVC and drop it in the hole, you could stack the pellets a half mile tall and have hundreds in the borehole before dropping in a few ounces of explosives and detonating a couple of miles below the surface to fill the hole without damaging the surface environment. You could then completely ignore it for the rest of human history. and move onto the next hole, with modern equipment you could dig such a hole in just a few weeks and each hole could probably contain a couple of hundred ton of waste material. Alternatively just throw the stuff into existing dried up gas or oil fields, these huge underground caverns would prove more than adequately isolated to store nuclear waste.

[Seret]

Dig a 5 mile deep 6 foot wide borehole in a suitably isolated location, cast the waste into a 6ft concrete pellet then coat the whole thing in an inch of PVC

What they actually do is vitrify the waste (mix it with melted glass and cast it into a block, essentially). This then gets packed into metal capsules and packed into clay.

[Nibb31]

During our history of nuclear energy usage we've produced just 70k metric tons of the stuff.

You're wrong by at least one degree of magnitude. The global production of nuclear waste is 20 000 tons per year. That's actually a lot of stuff to haul around safely.

Although live fuel and reactors are protected by thick concrete structures, spent fuel is usually stored on-site in pools that are only covered by lightweight hangar structures until it cools down enough to be carried away. Fukushima showed that this kind of waste storage is inadequate, because it relies on the integrity of the pool and the pumps to keep the water cool. If spent fuel gets left in the open air, there is a very real risk of radioactive fire, which would be hard to put out.

[Nuke]

if i were to want to get rid of it (and i dont, much of it is good fuel), i would dump it in the ocean right at the fault line to a subduction zone. this way it gets dragged down into the mantle with the sinking bits of the earth's crust.

to do this you need to bore holes into the ocean floor until bedrock is found, and then drill into it a hundred or so meters. place the waste canisters in them and cover them over. an old retired oil rig would work for this. then just wait for geology to do its thing.

Edited April 23, 2014 by Nuke

[bsalis]

A lot of nuclear waste can be re-processed and used as fuel. Whatever can be re-used, should be.

As for the rest, it should be buried in a geologically stable place, like Australia. Or perhaps get it into a subduction plate somehow.

[Elthy]

Im not sure if a subduction plate would that great. While most stuff disappears "for ever" chances are that your waste ends up in a nuclear eruption and i cant imagine a lbetter" way to contamine the whole earth...

[RuBisCO]

Fusion or accelerator driven sub-critical reactors. Make power out of nuclear waste, fission it into rapidly decaying or inert isotopes and develop more advance power plants all at the same time.

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

[Seret]

A lot of nuclear waste can be re-processed and used as fuel. Whatever can be re-used, should be.

Reprocessing is expensive and presents a proliferation risk. Unless you're specifically looking to obtain plutonium for an arms programme it's generally better to just leave the spent fuel intact and burn fresh stuff.

[peadar1987]

Okay, a few things from someone who has worked in the nuclear industry:

-The vast majority of nuclear waste isn't actually spent fuel. For instance, whenever we were working in a potentially contaminated area, we had to wear paper overalls so we didn't get radioactive contamination on our clothes. After use, we put them in a hamper, and the contents of the hamper were compressed into bales. These are technically radioactive waste, because potentially they have some very low-level contamination on them. In areas where there was contamination, but also the risk of cracking your head of something, we wore "bump hats", basically reinforced baseball caps. These were washed in the active laundry, and all the run-off from the washing machines there, as well as any drains and even toilets inside the reactor building is classed as radioactive waste, just to be on the safe side. Every time I used the toilet, I was effectively producing about 4 litres of "radioactive waste". In reality, you could probably go up to any of this stuff, roll around on it, lick it, whatever, and the only ill-effects you'd experience would be if you were daft enough to do that to the toilet water.

-Intermediate- and High-level waste is the stuff you don't particularly want to be around. Unfortunately there's too much of it to launch into space (several hundred thousand tonnes, we've probably only put a few thousand tonnes in orbit throughout history, and you need far more delta-V to reach the sun). That said, its activity is decreasing all of the time, and in terms of volume, there's about 30,000 m^3 of it. That's a factor of a billion smaller than the Baltic Sea, a factor of a few hundred billion smaller than the Atlantic Ocean. I think encase it in glass, bury it in a subduction zone in the sea bed, and even if it does ever escape, it will be so diluted that it won't be a problem anyway. There's simply not enough of it to make radioactive volcanoes as somebody in a previous post suggested. Put it this way, natural radioactive decay of elements in the earth produces about 25,000 GW of energy. That's compared to 570GW of energy generated by all the world's power stations (http://bit.ly/1jMAlms). Spent nuclear fuel produces about 10kW per tonne one year after removal from a reactor, so basically we're talking about already sitting on as much radioactivity as 2.5 billion tonnes of high level nuclear waste, just from natural sources.

[Simon Ross]

I favour the Larry Niven solution...

Convert the nuclear waste into a glassy solid

Place it in a pile in the middle of a desert

Place a fence around the pile with a warning 'Cross this fence and you will die'

Problem solved