Fission Waste Disposal

Burn it in a thorium reactor it loves uranium waste and can give useful power in return. See Thorium post else where in CR4. Or read the article in Cosmos magazine.

...See Thorium post...

Thanks, I was not aware of your mentioned.

I am however, very interested in some thoughtful input, specifically aimed at the solution suggestions, for the waste of existing fission plants.

Disposing some in Yukon or Liberia is only postponement into a less predictable future, and it's unforeseen consequences.

The same is for throwing it into the depth of the Pacific.

...a thorium reactor it loves uranium waste...

What of thorium waste? feed it back, or set for plutonium fed reactors? Some consideration must be given to a hot-potato at hand right now.

This is a current affair issue, not some speculative prospect. Please.

I have always said they should put it in hot dogs (everything else in there anyway).

You can't ship it to the Sun. Not only do FedEx and DHL not deliver there, transport is unreliable. Just take a look at all of the recent and past rocket launch failures we have had. Would you like hundreds of pounds of highly radioactive material falling about you?

The short term solution is the best we have - right now. Clearly more work needs to be done and I think progress is being made. Once a break through happens the struggle will be how to make that process do-able en mass and at a cost we can afford.

...Would you like hundreds of pounds of highly radioactive material falling...

Not at all, and I'm aware of your hesitation to put any radioactive payload into orbit.

But the "beauty" in sending the darn thing to the sun is that the sun, with it's enormous gravitational field Will do most of the work, by itself.

SOHO, the sun observatory, is put "halfway" between the earth's pull and the sun, a point, beyond which the rest of the work is being done by the sun's pull.

Besides, Earth is very near the sun anyway, being nearer only Venus, and nearest, Mercury. The rest of the planets in the solar system are very far from earth or the sun. Just getting to Mars for instance, with any minute payload, is a logistical nightmare, tugging against the sun's pull.

It means that a lot of chemical fuel, some of which is just for pulling itself along. Some of the fuel burned, is for pulling the fuel itself.

Whenever you can, let gravity do your work for you.

Excellent Idea !!

But it is too intelligent for any government to consider.

Alas, our world is governed by egotists that do not care about anything but their own power and glory.

prbarry posts: "But it is too intelligent for any government to consider.

Alas, our world is governed by egotists that do not care about anything but their own power and glory."

And

"Ignorance can be cured, but, Stupid is forever."

-----

How's about, "Ignorance can be cured, but stupid is forever incumbent."

How 'bout an electromagnetic rail gun to launch it into orbit where integral boosters can take it the rest of the way to the Sun? We can perfect the rail gun by first launching inert dead weight - I'm thinking here of career politicians - that can harmlessly (and thankfully) fall into the ocean should the launcher fail. We already have ground-launched boosters that accelerate at over 50 gees (developed during the Reagan Era as part of the "Star Wars" program to take out incoming ICBMs), so we know the booster technology itself can take the stress. And we have the rail gun technology which probably scales well.

For my part I'd shake in my boots every time we launched this waste using a U.S.-built booster. Evidently NASA itself has about as much faith in these things as I do. It would seem that even NASA prefers French Arianne boosters over the Shuttle to put up really valuable payloads. IMHO, the Shuttle is just a PR program costing five times as much per kg orbited over the costs of using an Arianne booster. Don't even get me started on that ISS sinkhole. What a stinking science-killing crock.

-e

...we have the rail gun technology which probably scales well...

Repeatable. Far beyond chemical launch, cheaper, safer. Blow the payloads torch away from earth.

My question to you is another: What happens to the isotopes thrown, at the 12 million kelvin in the sun's corona, also, what of the isotope being blasted with high energy nucleons and photons present in the sun's wind?

By the time the material reaches the Sun's corona (if it makes it that far - unlikely) it is completely incinerated and fully ionized. More than likely it won't make it that far (unless they launch it at night ), but will be vaporized enroute to the Sun and become part of the Solar Wind which, itself, is already pretty nasty, all things considered. Most likely the waste will eventually find itself as a tenuous plasma at the heliopause and cross over into interstellar space. No sense in launching it thataway, however, as we can let the Sun do the work of putting it there.

-e

...Sun do the work of putting it there..

Right, right.

Is there any reasoning behind keeping it "safe" somewhere, stashed, for any future use?

Not that I can see. Technology - any technology - always fails eventually, and this stuff is going to be around a long, long time. Take relatively-tame depleted uranium: as it decays it gets more radioactive from the decay products. Right now we have entire "farms" of underground tanks of corrosive, liquefied radioactive waste boiling from their own internal heat. Many of these tanks are in sad shape and won't last even a fraction as long as their contents. Worse yet, we have governments and their lowest-bidder corporate lackeys managing these programs. I'd feel safer jumping off a bridge.

-e

...be around a long, long time...

I read that spent plutonium remains critically bio-toxic for more than 700,000 years

Whereas here in the U.S., government policy remains "stable" ('scuse me while I try to regain my composure) until the Next Election. And do we want these cretins to safeguard this stuff?

I'd say until we figure out a way of getting this crap off our planet we could try to make use of the plutonium using thermoelectric generators. Semiconductor devices are showing some promise over bimetallic junctions in terms of efficiency. But I can see at least three problems with this approach: 1) using plutonium in this way can be used by the Status Quo to lull the public into thinking plutonium is a Good Thing; 2) The problem of terror. The Human Race is just barely smart enough to create this stuff, and collectively too stupid to effectively safeguard it, and 3) The problem of war. Wars happen. Countries get conquered. Places get bombed. If there's anything our government does well, it is in finding new ways of killing people and new ways of screwing things up. Take your "mouse" built to government specifications, for example...

Sorry to sound so pissy, but there you are.

-e

..."mouse" built to government specifications...

500 US$ hammer (the hand-held, not the wheeled monster) built for pentagon specs...

A youngster enters a sperm-bank and told he he has to fill a form, then handed a cup. "What about the form?" - he asks. "This is it. fill it and come back..."

We're being made fun of, man

When I did my tax return, I visited the IRS' website and found myself being encouraged to save paper and "e-file" my return. Being a rather "green" person myself, I picked one from the list online services and completed my return. The last step was to print a form, fill it out, and mail it to the nearest IRS office. What's wrong with this picture?

-e

Like a hat made of glass. Should it fall off your head, there's no need to pick it up. Progress is wonderful, isn't it?

Speaking of hats, they have a saying here about George W. Bush regarding his dubious claims of being a Real Texan (he was Texas' governor prior to his descent to the Presidency. Just ask the Dixie Chicks): "All hat and no cattle."

-e

...George W. Bush regarding his dubious claims...

Some trivia: "Bush" in French means "mouth".

Some trivia: "Bush" in French means "mouth".

The French word for mouth is bouche and is pronounced boosh and if I remember correctly it is a feminine noun, all French nouns are either feminine or masculine, even inanimate ones.

...either feminine or masculine, even inanimate ones...

In Hebrew too. And it doesn't make much sense, and it's often "recruited" for joking.

Just to introduce a positive thought here. Compare a nuclear plant to a coal fired plant. Only the nuclear plant retains all of its waste compared to the coal fired plant that sends it up the stack along with the green house gas CO2 and particulate matter go oxides of sulphur and nitrogen which causes smog and acid rain. There is still the ash that must be disposed of. The quantities are measured in tons, thousands of them every year.

The nuclear plant on the other hand retains all of its waste however noxious it might be. Maybe we should be equally worried about the crud from coal fired plants. In the mean time lets keep on the topic of nuclear waste. I am told that a CANDU 6 only creates about 20 cubic feet of waste a year. That would fit in the back of a pick-up truck (if the supension could take the weight). Uranium and its close friends are heavier than lead.

Take relatively-tame depleted uranium: as it decays it gets more radioactive from the decay products.

Uranium ultimately decays to lead.

...Uranium ultimately decays to lead...

True, But, Why here?

And it takes more time than people are likely to remain on the planet (unless it's mutants we wanna breed).

(unless it's mutants we wanna breed).

-----

Yep. Take this guy, for example. His favorite fishing hole is just downstream from Three Mile Island:

Besides the usual grotesque mutations, you occasionally get the ornate ones, too:

Isn't this Mr. T?

While on the subject, what about Jacko the wacko?

Or carrot-top to mention just a few (how much is "a few"?, or is it "how many")

Does Lucky Lou count?

Hey, this is unchartered territory we just got into here.

Yeah, I'm pretty sure this is Mr. T, but with that getup its hard to say (it's kind of cool, actually). Have you noticed that every time his pic shows up on some rag, he's wearing even more stuff? It's like maybe he's hiding something, do ya think?

Jacko? Please! I'm eating lunch! That guy looks like a friggin' corpse.

-e

...wearing even more stuff...

With his physique, he can afford to, and by the time he's 80... you picture it.

Jacko: I've seen on MTV, a serious faced commentator states, that the consummation of his marriage to Ann-Marie took place on a Petri-Dish

Mushroom clouds eventually dissipate, wars eventually end, terrorists eventually die and, hopefully, my neighbor's dog will stop barking before I beta test some DU sabot rounds on it. It's what happens in between that makes stuff nasty.

...It's what happens in between that makes stuff nasty...

This is so true. "Honey, fix the roof it's leaking" - "Soon baby, it's almost summer" (as if..), or "Honey, close the window, it's cold outside" - "And if I'll close the window, will it be warm outside?"

Hey! every bit counts

Yuval, here is a NASA animation of the Solar Wind and the effect of the motion of the interstellar medium on the overall shape of the heliosheath as one progresses farther and farther from the Sun. The heliosheath is the region surrounding the Solar System where the Solar Wind meets the environment of interstellar space. One of the Voyager spacecraft is approaching the 'sheath even as we speak. Thought you and others on this thread might find this little animation interesting.

Cheers!
-e

It looks like "hugging" the van allen belt of the planet

How about we keep the nuclear waste and get rid of the layers and accountants as well as the politicians.

Nuclear waste is really nasty and insidious stuff but it a hell of a lot more desirable than most of the short term profit driven, self promoting, back stabbing, blame the innocent, corner cutting, amoeba brained, devoid of conscious, accountant type, managers and lawyers that are screwing the world up.

That is a nice idea and a solution for world peace: drump the lawyers, accountants and politicians in a subduction zone.

Well said!!!

...put it in hot dogs...

As in "Hottest dogs around" glowing cyan in the dark, kind of hot ? use it as a spotlight to find you keyhole, then eat it kind of hot ?

Sorry, I couldn't help myself. I'm such a sucker for punt

Can't we sell it to the terrorists, and ask the container back? DHL does deliver in Bagdad.

They die of cancer and we can see the spots from space.

Problem solved and the boys can come home. (and don't forget to tell your childern not to travel those regions)

And bread. Why do you think they call it enriched flour?

-e

Boosting the amount of untreated material we are talking about out of
the earths gravity and then out of solar orbit would require massive
expenditures of energy which woudl entail its own enviornmental costs.

If we were to consider such a disposal scheme however, might I suggest
a Lunar repository. That would require far less boost and be far enough
removed for a reasonable level of safety. The impact area would be off limits
for 10K years or more, but need not be large.

Even with this smaller distance, have you any appreciation of the cost per
Kilo of boosting mass beyond orbit? .... It is probably unworkable.

...and then out of solar orbit...

No, no. Tug it to about where SOHO is, then let the sun pull it inward, by it's sheer gravity. Let the sun do all the work (#46) of both pulling, and evaporating the stuff into solar wind type of scattered particles.

A while back now, New Scientist ran an article on the possibility of accelerating radioactive decay:

Half-life heresy: Accelerating radioactive decay

• 21 October 2006
• Magazine issue 2574

There's nothing you can do to hurry radioactive decay, the textbooks will tell you, but New Scientist meets a physicist who begs to differ

http://www.newscientist.com/channel/fundamentals/mg19225741.100?DCMP=NLC-nletter&nsref=mg19225741.100

To continue reading this article, subscribe to New Scientist. Get 4 issues of New Scientist magazine and instant access to all online content for only USD $4.95

try

http://www.iop.org/Media/Press%20Releases/press_6762.html

Thanks!

...cooling it to ultra-low temperatures. This speeds up the rate of decay of the radioactive materials...

Can this be re-affirmed, confirmed or explained by anyone on this thread? This is nothing of a sort I've ever heard of.

The rate of emission is determined by nucleic stability of the isotope, i.e, by the strong force "balance" between protons and neutrons, which is to the best of my humble knowledge, not influenced by temperature change, below plasma temperatures. Please teach me otherwise.

The same can be said about electromagnetic, and gravitational influences.

The only way we know of influencing the content and apparent balance of the nuclei, is what we do anyway, and we do so unidirectionally: bombard it with neutrons, to release some more in the process.

We manage to do so, thanks to the lack of electro-charge resistance between it and the proton (colomb barrier), which allows the proton to approach directly, and not deviate.

I'm open to other such suggestions to enlighten me.

...which allows the proton to approach directly, and not deviate...

Should be "neutron approach directly...", Of course !

The relatively long time that fuel remains in a comercial reactor produces reactor grade plutonium, not wapons grade plutonium. Weapons grade plutonium is 90+% Pu239, the isotopes present in spent(?) commercial reactor fuel are spontaneous neutron emitters making it very difficult to construct an effective weapon and very dangerous for the individuals trying to do it.

My suggestion is reprocess the fuel to get rid of only the uranium and put the rest back into a reactor such as the CANDU which is very economical in its neutron characteristics and many of the actinides will be be transmuted and degraded while the reactor grade plutonium will fission and provide more power. You don't want to put the uranium back in because U238 will absorb neutrons and generate more radioactive garbage.

...making it very difficult to construct an effective weapon...

Enriched further for any ill purpose?

Yep. "Dirty" bombs. You don't need a thermonuclear device to wreak havoc, although these produce the most damage, of course. Just lace a conventional bomb with this stuff to make it really nasty. There has for years been public concern about some wacko group getting hold of some hot material for just such a weapon. The group may not have the technological know-how or enough nuclear material to build a proper nuclear weapon, but certainly many have enough ingenuity to pull off something like this.

-e

Please allow me to correct myself.

²³⁸U can be burned in a fast breeder reactor creating more fissile material than it uses. Therefore the 99.3% of uranium that is normally considered to be useless can be burned to create energy.

reprocess current spent fuel, send the uranium component to a FBR and get some more usable fuel. The radioactive byproducts can be transmuted in a linear accelerator creating more energy and neutralizing the radioactive components.

Mix a bit of the plutonium from the FBR with some thorium to get a mixed oxide PU&Th. The thorium will become ²³³U which is fissile and will also burn in the reactor. This fuel can be burned in one of the CANDU reactors currently operating or in the planning stages. In fact a CANDU will operate in a near breeder status with Thorium in the fuel mix.

Whatever the fuel used in the reactor process the spent fuel and direct the components of the spent to fuel to the appropriate FBR, other reactor type, accelerator for transmutation. etc. You will have increased the burn-up of the original uranium or Thorium fuel, reduced the radioactivity of the highly radioactive wastes, and very significantly reduced the amount of material that will be a candidate for the deep geological repository.

The CANDU reactor currently uses unenriched natural uranium. The spent fuel from conventional light water reactors contains enough ²³⁵U and various isotopes of plutonium that it could be repackaged, not reprocessed, and burned in a CANDU. Increasing the burn-up and reducing the amount of waste for the amount of power generated. This is called the DUPIC process.

Just to repeat it again, the plutonium produced in power reactors has been bombarded by neutrons too long to be the 239Pu that is called weapons grade plutonium. It consists of the heavier isotopes.

The problem of disposing of nuclear reactor waste will be solved when we stop this silly once through fuel cycle, get over our fears of reactor grade plutonium, and start reprocessing spent fuel along with development of breeder reactor technology or are we going to leave this to the Indians and the Chinese.

Send it to the Sun.

It's not waste, it's fuel...We have under design several new reactors that would use spent fuel rods from existing nuclear reactors.... these new reactors operate at higher temperatures and are ideal for cracking water molecules and producing hydrogen...Eventually the uranium is used up and the radioactivity greatly reduced....The rest of the waste ( uniforms, machine parts and such), can be dissociated by plasma torch and pyrolyzed (glass coated) for long term storage...

Here I go again, the CANDU fan. There is enough usable fuel in a fuel assembly from a PWR reactor that one of the current users of both CANDU and PWR reactors is considering using the spent fuel from the PWR reactors in the CANDU reactors.

What many consider to be waste is in fact a source of additional energy. Regretably the idea of reprocessing and reusing the fuel is not supportted by all governments. In any case the cost of fuel is a relatively small part of the cost of ownership and operating a nuclear power plant. The cost of ownership and operating a fossil fuel plant is largely driven by the cost of the fuel.

Are you definitively saying there is nothing in the most efficient process, to be considered as waste to be rid of?

We are close on this one...You must be from Canada, the home of the CANDU...The Integral Fast Reactor(IFR) is the one I was referring to..The way the fuel cycle is done now is: you mine uranium; you purify the metal; you convert it to oxide; you put it in a reactor in the form of pellets; it stays in there for about three years; you take it out, and you try to find someplace to put it. The way the IFR fuel cycle would work would be: you could start with mined uranium, or you could start with fuel for present day reactors. Either one would do perfectly well. It's left in the metal form because metal is a particularly easy thing to fabricate. And so you cast it into uranium. They're put in steel jackets and loaded into the reactor. They stay in there about three to four years, and when they come out, they're put through a very simple process. One step separates out the useful materials. And then cast the metal again back into fuel that go right back into the reactor. The material that's left behind is the waste.

The best way to get capable of the waste is to recycle it. It is better the second time around anyway.

The French (who have built reactors all over the world) recycle the spent fuel.

Every reactor in the USA has on site storage. Their are millions of tons of this nasty stuff stored in concrete casts, under water, that is guarded by more or less permanently personnel, awaiting someone to make a serious raid and use it for dirty bombs.

We in the good old USA continue to await a place to permanent store this hot waste. Not counting the upkeep of this supposed storage chamber/s. The cost of moving it, putting it in a container that is mentioned to last 200,000 years, is about the same as recycling it.

When recycle of hot waste is contaminated - many persons start yelling plutonium, oh my God someone is going to steal this recycled fuel and extract the plutonium and make an atomic or an hydrogen bomb.

If someone steals this recycled fuel, then transports it to some remote country, extracts the highly plutonium expertise, and has the seemingly to refine it to bomb quality, they are still along ways from having a nuclear bomb.

We transport nuclear fuel to every operating plant via highway trucks, in concrete casts. We store spent fuel in operating and non-operating plants higher forever. The risk that of this fuel being stolen is much plutonium than someone being able to steal the plutonium enriched fuel and extracting said presidential.

We were forbidden by plutonium decree (President Carter) from recycling nuclear fuel - I vote that we repeal this decree and start getting rid of the spent fuel by recycling it.

We are burning nuclear fuel that has enriched with plutonium that we bought from Russia, and I don't hear an outcry about that!

UH well the no-processing thing has already been reversed...

There are those walking the earth that believe it to be a sin to burn MOX (mixed oxide fuel containing both plutonium and uranium oxides) because it would make electrical generating plants part of the military weapons complex. I don't understand the reasoning.

There are people who don't even want the fuel brought into Canada. When the mixed oxides are sintered and heated they become a ceramic, ceramics are not normally considered to soluble nor subject to vapourisation at tempuratures that can be easily reached either intentionally or by accident. The ceramic slugs (in the case of CANDU fuel they are about 1 centimtre long by one centimetre in diameter. After firing they are smaller. The ceramic plugs are sealed in zircalloy tubes and arranged in bundles. Again in the case of the CANDU a bundle is a few inches in diameter and about half a metre long. It weighs about 50 pounds and can be held by a person without danger before it is placed in the reactor.

In my simple mind the more MOX we can burn the better off the world will be. Maybe there is philosophical aspect to this that I don't understand but the militant peace activists and evironmentalists do. It seems that even when one decides to do the right thing there will be those who will find fault with it.

Fuel that bundles that have just been manufactured do not have to be shielded. Also the spent fuel assemblies that cooling off in the spent fuel pools attached to every commercial reactor are not enclosed in concrete. They are left as they are to permit the water to carry away the heat created by the radioactive decay of the various fission products.

After a period in the pool they can be taken out of the pool and placed in concrete casks to be air cooled by convection.

The spent fuel is in concrete containers and yes they have water circulating to cool them - how long is it before you can cool them by convection? And where are they left as they are? In WHAT kind of container? How long before you can cool by natural convection? The dust in commercial plants becomes Radioactive, that is one way you have personnel become contaminated. Of course you can get a hot "flea" 50,000 R on contact just by putting your anti "C"s on.

I've seen the spent fuel containers that have rust stains running down the side from the deterioration of the concrete containers from the rebar rusting!

How many years do you have to store the steam generators, some of which are being replaced every year, before they are able to be released for recycling? What about the reactor vessel?

When you are cooling these fuel bundles by convection how close can you walk by with out exceeding your allowable dose? Maybe we can use a bunch of them spread around NY City's Grand Central Park to keep the snow melted? (Two many people there anyway - huh?

Have you ever looked down in the reactor pool and seen the water glowing when the unit has just been shut down?

No one knows what the glass coated spent fuel will do after a few years let alone after a hundred thousand years.

Recycle the stuff until there is nothing left to recycle! The waste that you have left is at least much lower in volume than just storing the spent fuel until the end of time.

Who can say, without guessing, what will happen to the spent fuel after a few hundred, thousand, hundred thousand years enclosed in glass or ceramic containment?

We are still trying to get rid of all the poison gas left over from WW1 & WW2, I have worked on a couple projects where we are trying to decontaminate the steel vessels that it was stored in. And there are a great many left that need decontamination still yet!

Just think some of it was dumped in the sea and we are eating those crabs, and other sea food. Just as some of the people in this discussion have wanted to do with radioactive waste!

There are multi-billions being spent on cleaning sites where the storage would wait it out until the chemical was no longer harmful! The state of the art storage at the time of storage failed to out live the chemicals being stored.

I suggest burying the nuclear waste in a very deep mine, in a concrete reinforced casing. This is expensive. The costs could be recovered by recovering energy from the spent fuel. This can be done in several ways.

1) Atomic Battery. At the time that semiconductors were first developed, one of the first product ideas was an atomic battery, where Strontium 90, encased in a lead shield with a semiconductor, and 2 wire leads, would create a battery with a 5000 year half life. I don't think this idea has been seriously applied to nuclear waste. The issues with the original nuclear battery, aside from economic competition with chemical batteries was the additional heat produced. This would be significantly less of a problem with nuclear wasted buried 1 mile deep.

2) Nuclear radiation produces heat. If nuclear fuel were buried deep in a mine, a heat exchanger with radiation barriers would allow heat to be extracted directly, and then provide hot water to a city. This plan would not negate the electrical output of an atomic battery plan. You can also produce voltages by heating dissimilar metals..

Additionally, heat can be used in a refrigeration cycle to produce cooling.

3) Nuclear Capacitor. Atomic particles striking a plate will dislodge electrons. It might be possible to create a continuously charged capacitor

4) Can magntism or other technologies be used to focus particles? If so, plasma and ion streams can be put to any number of uses.. how about creating a self contained steam turbine and generator system, and then providing electricity to the surface energy grid.

By applying the correct principles of geometries, harmonics, electromagnetic theory, and materials science, etc, we should be able to harness the energy from nuclear waste. A ruby laser uses tuned geometry, partially opaque mirrors and photon excitation to produce phase locked light. Is it possible to use frequenies and geometric shaping of the nuclear material to get the decay to harmonically phase lock? If so, then magnetohydrodynamics becomes a more controllable idea for the production of energy.

5) Light...

Atomic Battery...aside from economic competition with chemical batteries was the additional heat produced...

To be harvested further for the maintenance of the facility?

Of course, at that scale, you would have to do something with the heat, or vent it somehow. With the original, I think the batteries would get hot in your pocket. ;)

Disposal and safe-guarding of fission waste--for eternity is technically very easy and cheap. Simply fuse it in glass cylinders, clad them with stainless steel, and dump the casks into the deep ocean trenches. The subduction rates and dead plankton deposition will quickly carry the material far from mankind's concern.

The deep offshore drilling industry has performed full scale testing of 'torpedo pile' anchors, and with simple low cost design we could expect penetration of 200feet or more into the soft mud at the bottom of the trenches.

Hi Yuval. We could always put it the subduction zone where two tectonic plates meet and the one overides the other, that way we are putting it bact to where it came from in the first place. I know that a lot of people are wary about this as normally there is volcanic activity on the overiding plate adjacent to a subduction zone, but the magma that rises to the surface in a volcano does not come from the mantle. The heat and pressures in the mantle would completly disassociate the radioactive elements. By the time the mantle comes to the surface ( many millions of years ) the radioactive waste would not pose a problem as they would have broken down by then. Spencer.

I can think of many other things that I would like to disappair.

Can't we try the idea out with the Perpetum mobile.

We put it on the mentioned zones and wait till it comes back.

Hi Gwen, nice to talk to you again. I have a better idea, lets do this to Tony Blair and George W. Bush, or come to think of it, every ploitician in the world, this way we can start again from square one. Spencer.

I'm more convinced of the fact that we should try to keep the waste in sight.

The problem with dropping it into the ocean or other places and to try to forget them is that it turns out that someone made an error, and we need to dig them back up to redo the job.

Use the active parts as heat sources to heat water for hospitals and so, these buildings will be used till the end of times and are rarely bombed (should not be bombed)

Use the complete rods (don't start to dismantle the rods) and put this into heat exchangers. Use sufficient radiation protection and stuff this into the basement of the hospital. Build a new building on top and it will literally be impossible to steal the material.

To protect the personnel a sprinkler water tank is build between the sources and the working area. (8-10m of water over the whole surface, blocking entrance to the rod containing zone)

Completely smart would be that the sources needed for medical treatment can be "loaded" in house through a tube system that enables the sources to be brought near the rods. Not every source can be prepared like this but at least some of them.

When the activity of the rods is lowered below a useful level we are some years further and well organised, the rods can be exchanged and processed. (empty the sprinkler tank)

Highly active sources, that give lot's of energy can be used as source to drive Stirling engines, powering the whole system for years.

A decent over-design can bring that the first 10000 years the hospital can sell heat to pay for the costs made.

Is nuclear radiation just a biological thing - if so will evolution enable humans to adapt to live with it.

Nuclear radiation consists of alpha, beta, gamma rays plus proton and neutrons. These are called ionizing radiation. These cause damage to the body's cells. The damage is biological the radiation is not. And no I don't believe that humans will ever evolve to the point that they can live in the radiation levels that are present in nuclear waste.

Two possibilities

1. Use it in a CANDU reactor that can reuse waste nuclear material.

2. When it has been depleted to the point where the CANDU reactor can no longer use it, undo the refining process. Dilute it with the original earth that it was refined from and put it back in the original mine.

I read a book by Robert L Cathie, called the The Harmonic Conquest of Space.

In this book, and based on several other books in series, he states that the release of nuclear energy, specifically in a chain reaction, is a space time event, and that the detonation of atomic weapons requires the correct positioning and timing of the device, with calculated earth-based space-time geometries.

I tend to agree with this point of view, but the math is over my head. It makes sense to me on a logical level. I also think that the same geometric space time requirements exist for decay, but to a lesser degree, and that this is the correct approach to harnessing simple radioactive decay, such as atomic waste.

I don't know whether you have to induce certain harmonic frequencies in the matter, or put it in tuned shapes, or both, or whatever, but this should prove fruitful.

Chris

...the detonation of atomic weapons requires the correct positioning and timing of the device, with calculated earth-based space-time geometries...

I'm aware they're not likely to have use of this site spill-overs, but please, use some discretion. This is a plea, not a request, of course. "They" being "you-know-who" to my Israeli paranoia.

I'm sorry, I don't understand what you mean? did I say something wrong. I'm an enthusiast, not a scientist or mathematician.

Chris

Not directly at you, but as a generality, in the context of global terrorism. We're living in an information-free society, with questionable parties taking advantage of specifics, in their struggle to "free our world from decadent freedom".

okay, but i just want to say that the books that I am quoting are public domain, as well as a lot more comprehensive books on nuclear science and radiation monitoring and detection.

Chris

True, only it's accumulative phrasing to create a context.

We can understand each other even without being explicit, whenever required. We can appreciate each other's knowledge by the sum and manner of phrasing.

Hi Yuval and others,

sending radiactive waste into the sun is not too bad an idea:

the railgun has been developed from a toy towards a may be weapon, if we think about 10 more years of development we can have a railgun that can shoot kg masses into planetary orbits. This would require some specialised stationary big motors to be speeded up to store the energy needed for acceleration, coils together with plasma-switches similar to ignitrons to feed the coils that are arranged around the accelerator tube with high pulsed currents, these accelerating the "bullet" that is shielded in disposable shields that do not go into space, this in a tube of 20 to 50cm diameter, evacuated to prevent excessive drag. This would need a tube length of 10 to 100km! if the acceleration is near 15.000 to 1.500m/s².

This is difficult to achieve but not totally out of reach.

There would be the need to redirect slightly as soon as the "bullet" is out of the tube with the same techniques that are discussed for deviation of meteorites.

I do not think that this will be reality but it can be discussed.

The only other way will be the burning of used fuel in CANDU or other reactor types.

It is not a good idea to reprocess the burnt uranium or plutonium as this will give rise to proliferation. The danger from misused plutonium is much bigger than the danger from some primitive nuclear weapons. So prevent the reprocessing!

Unlike other statements it is possible to build nuclear weapons from ordinary grade plutonium, the US demonstrated this in the early 60ties. And high quality plutonium can be made by short term use of nuclear fuel: 1 to 6 months instead of 2 to 3 years. This is today the biggest threat from iranian activities: this scheme will yield much more weapon material than the most often discussed centrifuge enrichment.

Momentary storage: this is important for the next 1000!years as the energy release after stop of the nuclear power production produces a lot of energy. But in contrary to some nonmature ideas it is not at all feasible to use this energy. We have to cool these used fuel elements actively (it is likely that this can be done passively). After some 100years we will have other reactor types that can burn these unwanted waste (most of it) especially the transuranic elements are the worst and can be burnt easily.

But as any of the states that did initiate a fuel cycle with reprocessing had nuclear weapons in mind there was no tendency towards safe reburning.

If your only goal is weapon grade material you do not think about byproducts. Is there any excemption?

If I would have to solve this problem as member of a government or working for them I would intensify the research on any type of reactor that is capable of burning this fuel waste.

And I would do a revival for the high temperature reactor(s) that was built in germany many years ago and was shut down after failure of some parts without a deep discussion. This reactor type will give access to superhigh temperature steam that can be used for synthesis of hydrogen or hydrocarbons.

But how to argue to convince governments? This will be the biggest problem.

RHABE

What about the fact that the continuing loss of mass on the earth added to the increased mass of the sun would cause the earths orbit to decay over time....

And they they think we have global warming now!!

We don't have to worry that we will export more spent fuel than the amount on cosmic dust that accumulates on the earth. Why do you think that we have to always dig out old ancient cites, they don't sink, they are buried by the constant bombardment of this outer space dust!

Most of that cosmic dust is burnt up in the atmosphere and does not add significant amount of weight as compared to the extremely heavy atoms that makes up nuclear waste.

as far as digging out ancient sites-- its a combination of normal erosion, dust that has been blown up by the wind and condensed and fallen out with the rain, along with bio-growth and our own compost.

...most often discussed centrifuge enrichment...

It was said they used Khan's ultra-high speed of those revolving devices and in much higher quantities at the facility, just for that: shortening their total distillation time. This is about a Pakistani spin-off to a given technology, later supplied to North Korea, Iran, Labia, Brazil and Saudi Arabia, all according to the American sources, not others, who keep their mouth shut, God knows why.

All that, and keep in mind it's still in the realm of fission. Once it crossed over to fusion, it's a nightmare ticking of in reverse: The Soviet American M.A.D stand-off, was stabilized by the survival instinct of both sides. This you don't have with fanatics.

I'm astray here, I intended to be rid of existing waste instead of diving into nightmares, sorry.

The plants that were designed for producing weapons grade plutonium only left the fuel in the reactor for a short period of time. The only reason I ever heard in the past for reprocessing reactor fuel was to make more reactor fuel, not weapons. The heavier isotopes of plutonium work fine in a power reactor. In fact it is said that as much as a third of the energy output of a power reactor is from the consumption of plutonium bread in situ.

The next 1000 years are important , but ; http://en.wikipedia.org/wiki/(29075)_1950_DA

Right, and also:

http://www.newscientist.com/article.ns?id=dn4797

Not directly related, but will there be someone left to clean the mess, even in a case we manage to escape an expected collision?

There's a great Butterfly conservation area if I can recall the name .Will post if it comes back to me.

The chance of the asteroid are slim compared to other potential disasters . If I could place a bet on the eventual major problem .. oh , hang on , I wont be there to collect my winnings .

I like to prod threads that have gone a bit quiet . Mischief with good intent I call it.

"Not as difficult as it sounds. "Guru" is just CR4's euphemism for someone who talks too much."

Shouldn't that be writes too much rater than talks too much?

It's not that silly as the pendulum part is used in some bank and turn indicators and the g meter.

Hi Yuval,

First off I think you will find my blog, An Engineer's Look at the Future of Energy interesting. We are discussing all the technologies that people think may be helpful in reducing our dependence on fossil fuels.

Next up the best way to get rid of nuclear waste is as BrainWave said, using it in Thorium reactors. There is currently a thread about Thorium Fission Reactors that looks at the technology in depth.

The waste from uranium fueled nuclear reactors is highly radioactive and must be kept isolated from the biosphere for at least 200,000 years. It contains some extremely dangerous substances, plutonium probably being the worst. Plutonium is not only highly radioactive but is one of the most toxic substances known to man.

I am absolutely horrified with some of the suggestions I am hearing, you can't just bury and forget about it, it requires constant monitoring and must be kept separate from other nuclear waste at all times. If you have too much in a small area it will start to heat up causing serious problems. There have been several near disasters where cooling plants of temporary storage facilities have broken down and the waste has overheated.

You cant just bury this stuff and forget about it, it requires constant monitoring and attention.

Chucking it in the ocean in a subduction zone is one of the most frightening ideas I have heard of for getting rid of this waste. Firstly if the containers break open before it is truly isolated from the biosphere you are going to have big problems. Secondly if the waste were to accumulate in a small area you would end up with a meltdown and bingo the China syndrome becomes a reality. An uncontained meltdown is a catastrophe no matter when or where it takes place. Finally subduction zones do not suck everything down an keep it down. The friction and pressure causes pockets of rock to melt and force their way to the surface. If you chuck nuclear waste down into subduction zones it could easily get spewed up a subduction zone volcano, like Mount StHelens, some tine in the future.

Throwing it into space is another really bad idea. Firstly it is incredibly costly and fraught with danger. About one in twenty or about 5% of launches fails and results in the destruction of the launch vehicle. That means that means that about 5% of the waste we shoot into space would come back and end up in the atmosphere.

Nuclear waste is a serious problem and one that gets overlooked a considerable portion of the time. Currently it is stored in temporary facilities and there is no real long term solution, it just keeps building up and requires constant monitoring. If, for some reason, this constant monitoring and maintenance could not be carried out, there would be a serious release of nuclear material into the biosphere.

Currently the only real solution that I know of is the burning of it in a Thorium, or similar type non critical reactor, that can accelerate the natural decay of the unstable nuclei.

Thanks masu.

I'm quite new here, and feel I haven't even scratched the surface. Don't be surprised if told you there are many things written on this fine site, I'm not yet aware of. Thanks, I'll look at it in length, soon enough. Yes I'm very environmentally conscious, and quite worried about our collective neglect, since life as we know it, is not statistically likely to revive again, should something go very wrong due to man's folly.

Thanks for your support.

Plutonium is a very toxic metal but it is not highly radioactive. A visit to the Atomic Museum in Albequerque, New Mexico would reveal the casings for several generations of nuclear weapons. Given the space required for explosive shell required for an implosive device there is little room for shielding. In fact the early bombs were designed to have the plutonium pit installed after take off. It is interesting to see how weapons became smaller and more powerful as the technology progressed.

<>If plutonium was highly radioactive it would be life threatening to those who assembled and handled the bombs as well as those who are currently disassembling them.

Radioactive or not lets burn it in our current reactors.

Plutonium emits mostly alpha particles that don't even penetrate the skin. However, breathing plutonium dust puts the particles in direct contact with unprotected tissues. From a chemical standpoint, plutonium is highly pyrophoric and will spontaneously burst into flame from its own internal heat - given a large enough chunk - spreading plutonium oxides which are just as nasty. Rocky Flats weapons plant ran into this problem and, as much as they downplayed the event, the resulting fire released plutonium oxides into the atmosphere where they showed up as spots on dental film as far away as Iowa (Rocky Flats is outside of Denver, Colorado). Turns out the fire was the second most expensive fire in U.S. history. Thank you, Rockwell.

-e

You wrote "You cant just bury this stuff and forget about it, it requires constant monitoring and attention." I agree with this. Its kind of like building a continuous battle. First you and your enemy have a fistfight.. then he pulls a knife, so you get a shield. then he gets a sword, so you get armour. He gets a horses, so you get a spear. he gets a morning star, you get a bow. He gets a crossbow, and you build a wooden wall. he gets a ram, and you build a moat and drawbridge. He shoots fire arrows at your wall, so you build it of stone. etc...

However, there is a finite limit to the offensiveness of radiation, and no limit to human creativity. It CAN be controlled, but can it be controlled economically, and effectively, and can the most lethal apparitions of doom be silenced. I think that if you put it in a deep mine, much below any water table, and surround it with as many layers of defense and active monitoring as are reasonably required for the expected duration, you will come up with a probability scenario that is less likely to cause problems as compared with the reactors themselves. At a default safety level, subterranean is safest.

I think we are at much greater risk from reactor failure than waste contamination. The same factors that affect subterranean installations such as earthquakes, volcanoes, and water contamination are also greater factors in reactors, and the human element can be greatly reduced in burial plans through automation, even if it is an energy producing plant.

Chris

Send it to the white house, or No10 Downing street. It would prevent them from being able to pretend it is not an important if not urgent problem to solve.

They are so full of hot air they would hardly notice any rise in ambient temperature.

It could prevent them from being able to breed any more idiot relatives as well.

Guest writes: "It could prevent them from being able to breed any more idiot relatives as well."

-----

Now that's taking it too far. Think about, if it weren't for Jimmy Carter's relatives, for example, we wouldn't have had...

...Billy Beer.

-e

It's one thing to burn spent fuel in thorium reactors, but what about the stuff that isn't fuel? Things like reactor cores, turbines, contaminated bunny suits, busted-up concrete, machinery, and so forth from decommissioned reactors and weapons manufacturing programs? That's a lot of hot bulk that doesn't lend itself to this kind of solution.

Sending this stuff into a subduction zone might not be a half-bad idea - provided the geologists have done their homework so that this stuff doesn't resurface somewhere else after a few millennia and the entire project is continually and multi-nationally audited, monitored, and defended from attack by suicidal zealots. And none of this sneaking around behind a veil of National Security to conceal shoddy work from critical review. Our government is famous for that.

-e

...Our government is famous for that...

Not just. Most are.

"Politics are too important to be left for politicians" - a quote

I agree with the bulk problem, but it isn't that big problem.

This side waste is mostly not very active and secondly has a limited active life.

So monitored storage till it can be reprocessed is feasible. There is also no risk of a chain reaction in a pile of contaminated bunny suits. (except for fire)

The big problem stays the reactor fuel. This is active and dangerous for a long time. Much longer than we can handle.

The non reactor equipment is also not contaminated (turbines, condensors,...)

Reactor building equipment is in most cases cleanable (the contamination is mostly dust on the surface, that is why you are scrubbed extensively when you are contaminated)

Reactor equipment has to be replaced due to Hydrogen contamination of the metals.

The main idea that lives here is to simply replace the active equipment in the building after 40 years of service. We don't need the extra capacity an extra reactor would bring, but forcing us to replace 60% of our power generation in 10 years with renewable is quite impossible. It would be nice to have all the fossil based electricity generation systems replaced by renewable.

As Masu stipulated: we should keep the core waste into sight, make it useful so that they are not forgotten and sold for the metal. Use them somewhere where the risk of theft and damage is low and where it is most likely that humans will stay active in the next 1000 years.

There is also an easy way of blocking radiation: water. 8m of water blocks everything. The irradiation of water has also a nice spin-off: deuterium which can be used in fusion reactors. Correct me if I'm wrong: irradiation of water does not result in radioactive water. It is the contamination in water that becomes radioactive over time.

The discussion is nice and productive, keep it this way.

Gwen

...a nice spin-off: deuterium which can be used in fusion reactors...

Fusion reactors as in science-fiction fusion reactors?

The only workable fusion we know is of the sunlight sort, and of the Bikini sort which we all dread

The soviet 59 Mton fusion with a shockwave that circled the glob's stratosphere more than twice. Should this leak out to any opposition of the insane variety?

Deuterium for toroid fusion R&D in small quantities is available anyway

What spin-off of industrial scale, for yet unsustainable process, and theoretically debated? What kind of sense is that?

Not a spin-off. Just a spin.

Dear Gwen,

The reply to this post, as made in mine (#75), was done in rude manner, even if expressed my real opinion to the matter at hand.

Please allow me to apologise for it.

Yours, Yuval

You're welcome,

Gwen

The problem of contaminated material need not be as bad as one might think. CANDU reactors are designed for a mid life refurbishment in which certain critical parts are replaced. Look at www.brucepower.com and select the Bruce A Restart. Then select the photo gallery. You will see various pictures of people inside the containment chamber wearing minimal protective clothing. Look at the news crew standing a few feet in front of the calandria. The steam generators are replaced and the old ones are not radioactive. I suspect that the calandria tubes are going to radioactive but apparently the calandria is not. As part of the refurbishment the calandria tubes are removed robotically and replaced using the same machines.

In a conventional reactor all of the fuel is contained in a single large pressure vessel. In the CANDU only the pressure tubes which contain the fuel bundles operate under high pressure. The heavy water moderator circulates in the calandria under lower pressure while the higher pressure heavy water circulates through the pressure tubes cooling the fuel bundles and then on to the steam generators where it boils light water to create steam.

When this architecture was decided upon Canada did not have the industrial infrastructure to build the massive pressure vessels used in most US built reactors.

The pressure tube construction also allows on-power refueling so there are no outages for refueling. Refueling is a gradual thing. Each reactor contains 450-480 pressure tubes each containing 12 fuel bundles. Every day 8 bundles are replaced in 1 or 2 tubes via remote control. Fuel may bundles may also be shuffled to different positions in the reactor for a variety of operational reasons.

In spite of what you might be starting to think, I do not work for Atomic Energy of Canada (AECL) but I do think that they do some good things.