Nuclear Reactor Cores Disposal or Re-use

To be able to contain the Contamination, is the only thing I can think of.

Hot radioactively.

They are contaminated and unsuitable for further use. They would also be obsolete by the time they were decommissioned.

At Chernobyl, I had heard the radioactivity on its the lead shielding actually turned into gold............, but highly radioactive............. An Alchemist dream .....

Now I have to look for the source....:/

This one says no it ain't so.

http://muller.lbl.gov/teaching/physics10/old%20physics%2010/chapters%20(old)/2-Radioactivity.htm

Its called nuclear transmutation, Well this has more hope, it's a blog site, still looking for the Chernobyl incident....

http://forum.prisonplanet.com/index.php?topic=194568.0

You can't turn lead into stable gold....though you can turn gold into lead.

Oh I disagree. It is certainly easier to go from gold to lead. A little proton beam bombardment of lead to spawn some asymmetric collisions. With a little luck a few of the briefly created Bismuth atomic nuclei will spit out a pair of alpha particles. The individual gold atoms will be difficult to detect and with so many high energy protons coming in, a few milliseconds could be considered stable.

Just having a little fun here.

I like your device for applying new perspective to 'stable'.

It seems like it might come in handy.

This must of been what I was thinking about, it was Russian scientists discovery, but I must have just tied it to Chernobyl

http://chemistry.about.com/cs/generalchemistry/a/aa050601a.htm

http://coldfusionnow.org/lenr-and-transmutation-it-is-going-to-happen-soon-than-you-think/

Here's an excerpt:

"In 1972, Russian scientists found that the lead shielding of an experimental nuclear reactor near Lake Baikal in Siberia had unexpectedly turned to gold!

Unfortunately such gold is likely to be radioactive, and would decay back to stable lead, whilst releasing dangerous radiation."

You can make gold from other materials, it's just not cost effective....and I might add you can power a nuclear reactor with spent cores...

http://www.startribune.com/opinion/commentaries/210648751.html

http://www.technewsworld.com/story/78213.html

Never really said it was viable, but it also isn't permanent.

"New" fuel Assemblies are not radioactive and are often shipped by normal trucks over the road. They don't become radioactive until they are used in the reactor. From that time on they are dangerous and require shielding from the general public.

Starting up a new reactor with all new fuel requires a radiation source be included after the fuel assemblies are installed in order to initiate the reaction.

"New" fuel assemblies actually are radioactive..... but then so are bananas which are also shipped by normal trucks.

The truck driver is radioactive, too.

...and it is especially noticeable after his breakfast of bananas and fuel assemblies.

OK, I'll give you that one!

The fuel rods that power a nuclear power plant ARE radioactive. They also are made up of many small fuel pellets that are stacked and combined inside of the metal rods to create the fuel rod.

Hydrogen is a byproduct of ALL nuclear fission and is dealt with. The explosion at Cherynobl as well as the Japanese plants were of the hydrogen gas. When you have a nuclear reaction one of the product is the alpha particle that consists of the helium nucleus and beta particle that is a hydrogen atom plus some other particles.

As for a place to deposit the spent fuel they at last that I knew were still being held at the site where they were used and could not be transfered elsewhere.

The particle in beta radiation is not a 'hydrogen atom plus a couple others'.

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A beta particle is an electron (for beta minus decay).

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.Beta minus decay involves the conversion of a neutron to three particles: an electron (beta) a proton, and an antineutrino.

. This decay is typically delayed from the actualy fission event.

'.... A spent core will no longer be able to produce sufficient heat with all moderating material removed (full throttle)...'

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A minor correction is needed..... 'all moderating material removed' isn't necessarily 'full power' (which is what I assume you mean by 'full throttle').

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In reactors that operate mainly by thermal fission (most reactors), a decrease in moderation leads to a decrease in power (and in increase in moderation leads to an increase in power).

As others have indicated, the heat energy is of a lower quality (low temp). Back in 1976, I knew a mech. engr. that worked on a team that studied using the waist fuel rods to heat cities. I recall him saying that cost, and public fear killed this.

A reactor under full steam can produce a few 100MW. A collection of "spent rods" in a cooling pond produces a few 100kW or less, decaying fast at that. While still quite "hot" radiation wise.

It would be too much trouble for little power, trying to squeeze the last erg out of it.

That would be 1200 megawatts?

As a minor semantic matter, it is fuel rods that are discarded (or possibly reprocessed). The reactor core (singular) is where the rods are inserted.

This is not universally true, though it is generally true for most commerial nuclear reactors.

My understanding of a core is that it is what contains the fuel rods.

Some cores do not have fuel rods.

Some cores are made of fuel assemblies, for example. There are no rods to be replace in that case. The entire core is replaced when needed.

Maybe that's what Ron meant.

Regardless of Ron's intent, his use of the term 'core' does not require correction. Depleted reactor cores are removed and basically discarded.

They make pencil leads out of them (for government workers).

I worked at the Portsmouth Naval Shipyard back in the 60's and helped design a railway vehicle to transport a spent reactor core from the USS Nautilus to a disposal site out west. The railcar was fitted with cooling equipment to keep the temperature down. It seemed to me that there was stll a lot of "life" left in that core that could still be used to generate steam to generate electricity. I will accept the idea that there is not enough "heat" left to be usable. Thanks all. Just for your information, I had to go into the reactor room where the core was located dressed in special clothing. It was so "hot" (radioactively), that one would get a month's dose of radiation in just 1/2 hour. I don't think I glowed in the dark.

Did you feel like a big yellow duckling in the anti-C's?

Wearing anti-C always feels to me like I'm doing a high effort, poorly executed, rendition of a baby duck: all, hot (temperature wise) and sweating which eventually makes your shoes start to squeek inside the yellow overboots.

Yeah, why? I hear that Iran and Syria are in the market!

It's an emotional/political/security issue. Emotional because of NIMBY (Not In My Back Yard), political because nobody wants to be accountable, and security because of the threat of terrorism and/or nuclear blackmail.

Although I believe we are using core and fuel bundle interchangeably, there is a big difference in their short and long term radioactivity. The core is a metal structure that holds the fuel bundles. Like any originally non-radioactive material used in close proximity to the fuel rods, it has become irradiated but contains no radioactive material so there are little long term decay products, it is "simply" a radioactive hazardous waste product.

The fuel bundles are where the radioactive action is, and theoretically that heat could be captured and used, but it is low quality and the quantity is always decreasing over time. Here's a piece from Wikipedia:

"...Rather than manage the pool's inventory to minimize the possibility of continued fission activity, China is building a 200 MWt nuclear reactor to run on used fuel from nuclear power stations to generate process heat for district heating and desalination..."

Here's a NRC piece that gives us a hint at the amount of heat that is available:

"...Dry cask storage: The NRC has also authorized nuclear power plant licensees to store their spent fuel on-site in NRC-approved dry storage casks. These casks:

• Are located inside the plant's protected area.
• Are designed to resist floods, earthquakes, tornadoes, projectiles and temperature extremes.
• Are robust, with very thick metal or steel-reinforced concrete outer shells and a sealed inner metal cylinder.
• Allow the spent fuel to cool without fans or pumps by drawing fresh air in at the bottom and allowing the heated air to rise through vents at the top. A typical cask emits roughly the same heat as a home-heating system (highlighting mine)..."

I also remember working on a study of using the waste heat from the SFP (Spent Fuel Pool) as the source for heat pumps used to heat the office space at a nuclear plant. There are no safety issues because otherwise the heated water is passed through heat exchangers and the heat just becomes part of the plant's cooling water requirements.

So to answer Ron's question, yes it can, but no it won't (at least in the US), be used, for the reasons stated in my opening sentences.

'.... Like any originally non-radioactive material used in close proximity to the fuel rods, it has become irradiated but contains no radioactive material so there are little long term decay products, it is "simply" a radioactive hazardous waste product.....'

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'....it contains no radioactive material...' is no longer necessarily true once it has been exposed to a strong neutron flux.

Even though cobalt has been minimized in materials that are exposed to a strong neutron flux, levels of contamination are typically large enough to represent a hazard from Co-60 from alloys used in the core and reactor vessel and associated plumbing. Co-60 has around a 5 year half-life and the decay energy is relatively strong.

Ni-63 (~100 yr halflife) and Fe-55 (~2.7 yr halflife) also represent significant decay activity concerns after neutron irradiation.

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Any piping/plumbing in contact with the primary fluid for a significant also has a good probability of being contaminated with CRUD (named after first investigated occurance: Chalk River Unidentified Deposits). CRUD is typically highly irradiated wear products that have passed through the core regularly entrained in the primary coolant and then at some point adhered to the piping/plumbing wall. There may also be fission products, or fuel components in the CRUD if the cladding integrity has been compromised by fuels swelling/fission product gas pressure.

About 15 or 20 years ago, I read about a device that produced electricity from spent fuel rods.The theory of operation was:A fuel rod was surrounded by a copper wound coil(s.) The neutron emission excited the electrons in the copper wire. The voltage was stored in a capacitor,and an oscillator circuit converted the DC into A/C and transformed it into the desired voltage.

This produced a usable amount of power,enough to power an average home.These could be housed at the nuclear plant, and the output combined with the existing grid.At least it would not be wasted heating a salt mine.

So why has this possibility not been explored, or perhaps it has, and was not viable.

Has anyone else heard of this?

In a previous thread on CDR4 this subject came up. In my "need to know" mode I contacted Canada Nuclear and asked what fuels the then new Candu 600 could handle. The answer I recieved was that it had been completely successful at handling spent uranium from US PWRs as well as the Thorium fuel bundles which my query was actually about.

There is no need for witchcraft on this subject... no K-tel coils for your uranium bundles. There is still plenty of energy recoverable with known technology.

I think you are remembering something pretty closely, but maybe a little off.

The products of fission in spent fuel have nuclei that are high in neutrons as compared to protons, but the decay method is not largely by emitting neutrons. Also any neutrons emitted would not have a large chance of interacting with a coil of copper wire.

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Typically fission products undergo beta (minus) decay to correct the excess of neutrons in the nucleus. Beta (minus) decay involves the ejection of an electron from the nucleus. Being charged, the electrons would almost certainly interact with even a very thin coil of copper.

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I think you description is valid with the just the mistake of remembering the interaction being with neutrons instead of electrons.

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I also remember a technology being discussed wherein hafnium that had been irradiated (it is a poison used in control rods) was being used as a 'quantum battery' if emits a higher energy gamma when triggered by a lower energy microwave signal....if I am remembering correctly.

You are probably right about that,a few cobwebs do seem to creep in once you pass the third score of years.I am pretty sure there were multiple layers of copper coils,like the primary of a transformer,and it seems like there were even more windings in the secondary,so in effect,the rods were in the center of a step-up transformer.Of course, I could be wrong about that also.At any rate, any safe method to put the waste to use is better than what they are currently doing.

It's not that fancy, simply an array of thermocouples with the hot junction in the warm radioactive material and the cold junction embedded in the protective shell. They're used in satellites and deep space probes for powering them when they're too far from the sun for photovoltaics, as well as remote locations with limited insolation.

From Wikipedia:

The radioactive material is euphemistically referred to as the "Heat Source".

Dear Mr.ronseto,

The spent Fuel from Nuclear Reactor - is still RADIO-ACTIVE, cause injury to living persons and animals.

If you refer/read the book,NUCLEAR POWER ENGINEERING by El-Wakil, you can find more details of the problem on account of handling the spent wash fuel. I had the book, but it is in a damaged condition. Now a days lot of soft copy/e-Books are available. I will try to copy and send through personal messaging in CR4

About 30 years back (if I remember correct) one Nuclear Power Plant was closed and it was concealed by pouring 1300 MM of CONCRETE over the plant which has cost more than the Plant Cost. This was the WORST NUISANCE to be handled .

DHAYANANDHAN.S

For many years my Brother-in-Law working for a private contracting firm decommissioning nuclear reactors throughout the US and Canada. He now works for Lockheed-Martin at the KAPL site in Niskayuna NY. From what I remember him discussing long ago, the reactor components are removed after a period of time because the metallurgical strengths are seriously degraded from neutron bombardment.....with most, if not all metals exhibiting fractures and other weaken states.

I may be wrong on this, or misunderstood him. It has been about 25 years since we talked about this, so my gray matter may be a tad on the "fuzzy" side.

I used to kid Peter that he "glowed in the dark" so my sister could find him in the sack at night! My kid sister naturally got pissed-off at me whenever I kidded around about this, which was often! LMAO!!!!!!!

They are decommission the nuclear plant in Two Rivers, Wisconsin. The say it'll take all of 20 years to do it.

The key thing is that fuel in a reactor is in a critical configuration where you can get as much heat as you want and can handle, controlled by how may neutrons are flying around. Typically that heat production rate is on the order of 30,000 to 40,000 kW per tonne of uranium in the core. By the time it is "spent" after 3 to 6 years it has produced 1 trillion kwh of heat, and about 1/3 of that in electricity, from each tonne of loaded uranium. It is spent mostly because it can't help sustain the critical configuration.

In contrast, spent fuel produces only radioactive decay heat at a rate of only 10 to 20 kW / tonne after 1 year of decay, and 1/10th of that at 10 years.

Short version. Folks that care take the time to learn and understand and see the waste as something we can use. BUT the majority of folks do not know the difference between a crouton and a neutron. So it is

both technical but mostly I guess the best word is political that we wast so much energy in so many ways. It is just a flat Shame.

Most of the posts have covered a great deal of the technical side of things. But I can add a few.

As a Brand new reactor goes on line due to the neurons flying around at 50k MPH if not for the Control

rods to slow these racing particle down to about 5K MPH a lot of bombardment of particles changes

the contents of the core to something other than they were. A couple examples would be Uranium 238 gets hit with a neutron at 5K to 50K MPH and it may split thus making up several lighter elements but it also may absorbe the neutron and be converted to Plutonium. This is acctualy a prety dam cool thing

as it is the basis of a Breader Reactor. Convert the almost useles Uranium 238 to useful plutonium 239. Then run the reactor on Plutomium that was made from the almost useles uranium 238 ( Uranium 235 is what runs a reactor. Mined Uranium out of the ground has to be Enriched to have a higher level of

Uranium 235 else the reacor will not run. Other elements in the fule rods get changed into other isatopes and elements and some compounds that acctualy cause the reactor to not work well. After running longer more changes happen and the reactor speeds up again or is no longer hinderd. Also the design of the core alows for these changes and the operators can make adjustments to keep things running.

But. Personaly. I would use the very safe Glasificatin process developed by Batell Labs if I recall that turns the core waste into a glass like substance and then that substance is stored on a several layer of different materials and put way underground in salt formations. But the crouton folks will not allow it. They do not stop and think. If you put something that far underground and something happens that would couse the earth that far down to end up on the surface then this would take and event so biblical in proportion that we and they would not be worried about what is brought up from that far down but rather what caused such a disater. Only a few things could posibly do cuase such an event and that would be an ateroid hit of such a size and speed that we are not going to worry about ANYTHING

because we and all bacteria will be dead. A Volcano could do the trick but when you are putting this stuff in a place that is so stable from a geollogical standpoint that if things started to change in the next

25,000 years we would have time to move the stuff to another location. But things do not happen that fast. EVER. Not Geologicly.

Thus we should switch to Thorium reactors that are so much safer than anything ever made and very clean and very safe. But that will not happen ether as folks will get the hell scared out of them by those that stand to gain from NOT using nuclear power getting those that do not know anything afraid.

I would like to go on with more but then I would be a little of topic. But I will say this. If we did store all the spent cores AS GLASS Encased in Stailess Steel and Contreate and other readaly available stuff

we can harness that engergy. But it will not happen.

Jimmy Joe Jetter

PS Sorry my spelling is not better.

However, U-238 is NOT useless if we used a "fast neutron" reactor such as the IFR or PRISM. Fast neutrons will cause fission of the U-238 molecules--and also thorium.

PS: Try using the spell checker.

If I'm not wrong around twenty or thirty years ago there was a lot of discussion about sending this stuff into space. So it must be pretty undesirable. As well a big headache to properly dispose of.

There was also a lot of discussion even prior to that about sending Pan Troglodyte into space. That wasn't just idle talk, some Pan Troglodyte actually was sent into space. It certainly can be a headache to deal with as it ages as well.

So it must be even more undesirable than spent fuel, right?

Yes. I'd say about as much as sending some Hominin equiped with a few more cc's of gray matter.

In this regard I only have one word to add.

Fukushima

The unfortunate Fukushima accident was not caused directly by the nuclear reactor. Instead it was caused by natural forces; the reactor got involved due to lack of coolant flow.

The newer fast neutron reactors will not have this problem. They will safely and passively shut down if the electric power is cut off. The liquid sodium coolant has enough capacity to absorb the residual heat within the core, plus there will be thermo-siphon cooling.

I wish there was a 'Bad Answer' button. I realize 'Off Topic' counteracts any potential or existing 'Good Answer' ratings, but 'Off Topic' isn't the rating I want to give. It isn't the rating that this type of answer deserves.

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Q: Why isn't spent fuel put to better use?

A: Horrible Natural Disaster in the form of a huge earthquake with massive loss of life, complicated by the severe nuclear accident caused by the extreme severity of the earthquake and tsunami.

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Are you suggesting that had the heat from the spent fuel been put to better use, the earthquake gods would not have been so enraged as to release such a violent earthquake in the vicinity?

Hey, you can call it off topic, bad answer, whatever. While you are at it why don't you go off on the spelling bee folks or the terminology folks. I am dead on topic my friend. What to do with this stuff is the problem.

So, It was simply put out there as a reminder that we haven't figured out what to do with this crap and our current options are, well as Fuku illustrates clearly, not even close to adequate. Yeah, we're damned impressed with ourselves right up until mother nature or human nature reminds us of how inadequate we are to be playing with this stuff or the fact that we are playing with this stuff and haven't even solved all the problems yet.

It was offered as an illustration of just how vitally important Ron's question really is to our future.

Perhaps a bit of elaboration would have helped make that clearer, although I think if you remember the biggest concern they had was the spent fuel storage containment failure and subsequent loss of cooling water resulting in release of radiation into the environment and potential of nuclear fire.

I have yet to think of a good answer to the problem of what to do with a whole bucket load of unintended extememly hazardous waste from all sorts of industries not just nuclear. Dumping them in China is just our latest stupid solution.

Granted I like rail gunning it into the sun but..........

Any ideas are always welcome and a good discussion is one that covers the issues not the terminology because the stakes are incredibly high and we tend to minimize them or get distracted by the words until we have to deal with the worst case scenario flowing into our backyard. Then no one cares what you call it, we just want it fixed.

So far we have been lucky and that is all there is to it. Sooner or later luck runs out.

I hope that clears thing up a bit. Am having a day that does not leave a lot of room for detailed elaboration.

Sorry, social workers tend to think in human costs and terms. For us its not all academic, its personal.

Rashavarek: Looks like my answer should have elaborated a bit more--I was afraid of being too wordy! We do have a solution to the "waste" problem. It is a reactor that uses fast neutrons instead of thermal neutrons. This fast reactor will use as fuel the "waste" from the presently used thermal reactor plants. This "waste" will produce bunches of energy to benefit mankind. Please check out the many benefits of the fast nuclear reactor, aka IFR and PRISM reactors.

'... I am dead on topic my friend....'

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That was exactly the reason for my lament over the lack of a 'Bad Answer' button.

The answer was not off topic.

The emotional bleat was aimed exactly at the topic, but to borrow a phrase from Wolfgang Pauli, "It is not only not right, it is not even wrong".

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That said, the problem is not rectified in your follow up comment. Your complaint is more worded, but you offer no suggestion for an alternative. Complaining without a viable alternative is just whining.

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Sorry, the impression I get from your comment is that social workers tend to think they are the only ones that think in human costs and terms. Regardless of how personal you rate your own comment, complaining without suggesting a viable alternative is the quintessence of the pejorative meaning of 'academic', i.e. speculative without being aware of the outside world. With the chiding you tossed in, it becomes clearly pedantic.

Funny, I thought railgunning the waste materials into the sun was a possible disposal solution. They are studying it at Max Planck but what do they know. I guess I was wrong.

As far as illustrating the failed ideas of the past, I stand behind the Fukushima example.

Keeping your waste in open swimming pools and hoping nothing bad happens is a proven fail of epic proportions.

BTW Fuku was supposedly earthquake proof built by folks with lots of earthquake and sunami experience but also a proven track record of supreme arrogance. There in lies the problem.

In the something to think about catagory. Most nuclear containment structures were designed before the first 747 flew. How well will they withstand the impact of a fully loaded Airbus 380?

If you can fly a plane into the most secure airspace on the planet and strike the pentagon how much trouble will they have hitting a reactor?

And of course we have just as much if not more security over our waste storage facilities right? Down wind of any?

As far as the waste itself, We've never lost any. We've never had transportation incidents. We've never had containment failures. Hell we can't do anything wrong it seems.

Or answer this question, How far away from (insert reactor or waste facilty) is (insert major metropolitian airport) and how much intercept time is there for a cover flight to take down a terror strike airliner? Provided you could get anyone to make that decision in time.

Lastly, with an education in human psychology comes the unpleasant realization that we are one of the most destructive forces on the planet. Second to none when it comes to our ability to destroy each other in ever more creative and spectacular ways. We are also second to none in our ability to deny just about anything we don't want to accept.

BBBLLLEEEETTTT

Now on to the Prism reactor concept. I am not that familiar with this so If this is a viable solution what's keeping it from being implemented? It's got to be better than lead lined 55 gallon drums and hardened casks or caves.

BTW Fuku was supposedly earthquake proof built by folks with lots of earthquake and sunami experience but also a proven track record of supreme arrogance. There in lies the problem.

Anyone in engineering or has an engineering background knows that you can't win against Mother Nature. And they would never say that.

It's like saying the Titanic is unsinkable......

Thanks for the stellar example of yet another time when our balls were bigger than our brains.

Like it or not, They said it was unsinkable. And believed it.

Like it or not they said it was earthquake proof. And believed it.

The list is long and storied.

One thing I have learned, degrees don't make you smart.

Letters behind your name don't make you right.

Neither Murphy nor Mother Nature is impressed.

One thing for sure, no one is trying to impress anyone here.

I still don't see your 'shoot it to the sun' fantasy as a viable or even helpful solution to what occurred at Fukushima.

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I also don't see your 'shoot it to the sun' fantasy as a viable or helpful solution to the concerns you have about large airliners being kamakazied into reactors.

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I do see your 'bleating' a good self-portrayal. Thank you for that part.

We'll let the personal attacks slide and stick with the point.

I asked for some more info on the Prism / IFR reactors and why we are not moving forward on those.

I offered the rail gun solution as an alternative to on-world storage of something that will not cease to be a problem for a very long time.

As for the other things I have put out there, we can take that argument to a different section of the forum. Here, I'll even open the topic for those who want to go round that track. I'm an old Monty Python fan so its called "Is This The Right Room for an Argument?"

I asked for some more info on the Prism / IFR reactors and why we are not moving forward on those.

Info on PRISM/IFR might be considered off-topic in this thread. Why are we not moving? In the past politics was the main hindrance--40-50 years worth. I think it is starting to move again, but there is a lot of inertia from people like you who don't understand. The brand new movie Pandora's Promise, which I haven't seen yet, may help; at least the advance publicity makes it sound good. Also the book Plentiful Energy which I am just starting to read.

Lehman57 wrote:

but there is a lot of inertia from people like you who don't understand.

Ok, I am assuming you mean my concern about the possible misuse of some the plutonium. The thing that caused Pres. Carter to ban the reprocessing. The whole terrorist thing.

I am not in any way shape or form against trying something new. I am dead set against staying stuck in ways that have now been proven inadequate. That's been my whole contention. Lets do something different. I don't care if we make a mistake as long as its a new one.

I live in Wisconsin. We have a state motto here. "long before O-man or MSNBC borrowed it"

FORWARD

A new chemistry for reprocessing has been developed and proven; however, by my understanding, not on a commercial scale because research/development was shut down by Clinton in 1994. The new chemistry, pyroprocessing I think it is called, cannot separate out plutonium for use in weapons; instead the plutonium becomes part of the new fuel for use in generating electrical energy.

'....I offered the rail gun solution as an alternative to on-world storage of something that will not cease to be a problem for a very long time....'

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A good thing to consider might be a comparison of the total number of failed space launches (and the dispersal of the cargo) as compared to the total number of nuclear terrorist acts.

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The level of sophistication necessary to build and deliver anything above a dirty bomb wouldn't require an investment that doesn't make much sense for a terrorist organization. It certainly doesn't leverage the advantages a terrorist organization can have.

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On the other hand, a dirty bomb doesn't even require nuclear waste. There are plenty of long lasting problematic substances that would be sufficiently 'dirty'.

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There is no way you are going to be able to shoot all the dangerous stuff the sun or moon. If you intended to shoot just the most dangerous stuff, carpet knives, ammonium nitrate fertilizer and pressure cookers have been much more of a threat than nuclear material.

Shoot it to the sun...good idea,but let's do it at night,so there will not be a huge CME on our side of the sun when it impacts,that would send it right back at us!!

Spent fuel rods as they come from the reactor still have to be cooled for many years, however they are not producting enough heat to have enough payback to make them a viable, profitable commodity.

They can be recycled and the recovered fuel is even better that it was the first time. Our (mine anyway) president Jimmy Carter put a presidential decree that the US would not recycle fuel. He was afraid that the small amount of plutonium would somehow be stolen and used to make a tarriest bomb.

Whole governments spend an enormous amount of money to try to do this with their own spend fuel rods, and often take years to (if ever) to make a bomb.

I would vote to recycle fuel rather than store if in concrete casts (barrels) that can be used to make a dirty bomb.