What is spent fuel anyway?

December 27th, 2007
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There’s a lot of talk about “nuclear waste” and what should be done with it. There are different categories of radioactive waste which include everything from very low level material like contaminated lab coats and beakers from radiological tracers all the way up to highly concentrated high-energy radiation sources. Generally the majority of such waste is not especially difficult to deal with, as much of it is not actually very radioactive at all. But there is one kind of “waste” which has been the subject of a lot of debate recently, especially in the United States.

That material is “spent fuel,” the uranium fuel rods from reactors which have been used for power generation and are no longer suitable for sustaining fission in typical reactors. This material is currently being stored on site by nuclear power plants, as it has since the 1970′s. Much of it is in “spent fuel pools” where it is submerged in water for shielding and cooling. Other, generally older, spent fuel is in “dry storage” in concrete or metal casks also primarily located on site at nuclear reactor locations. In the US alone there are hundreds of thousands of metric tons of spent fuel in storage and nuclear plants and elsewhere. Even more is located at other sites worldwide.

The current plan in the US is to move the spent fuel by road and rail to the Yucca Mountain federal repository site in Nevada. There, the spent fuel and other “waste” materials would be placed in tunnels, located deep within the rock of the mountain. Geological studies have been done in the area and the Department of Energy is confident that the materials could be safely entombed in the mountain for hundreds of thousands of years. The repository was supposed to begin accepting shipments in 1998, but due to opposition and delays it will probably not be fully operational for at least another decade.

Needless to say, this has been an issue which has garnered the attention of the eco-stupid movement. It has also been the subject of criticism on the pro-nuclear side. Many other countries manage their nuclear waste through reprocessing programs. In the US, all reprocessing activities ended by the Carter Administration. It was claimed that reprocessing of nuclear fuel could lead to proliferation of nuclear weapons. Apparently, Mr. Carter was not aware that the US already had thousands of tons of weapons-grade material stockpiles and tens of thousands of nuclear warheads already assembled, and therefore the recovery of added plutonium would not really change much, especially considering that reactor grade plutonium is not suitable for use in weapons.

Despite the fact that many seem to have opinions about what should be done with spent fuel and the fact that spent fuel “waste” is one of the biggest issues in the anti-nuclear movement, few seem to even know what the material is made of. So here’s the breakdown of what we’re dealing with. The amounts will vary depending on the type of reactor, but these numbers represent a typical lightwater power reactor, like those used in the US and around the world for electricity production:

Uranium: ~94-96%

The fuel that goes into a reactor starts off as uranium and when it comes out, it’s mostly still uranium. Natural uranium consists of about .7% uranium-235, which the remainder being almost entirely uranium-238. Since uranium-235 is the easily fissionable isotope, it’s concentration is increased through “enrichment” for use in reactors. When the fuel goes into a commercial nuclear reactor it is usually around 3% uranium-235. After being used, it contains about .9%-1.2% uranium-235, which has not been fissioned by the reactor. This is generally higher than natural uranium, making the material an even richer source of U-235 than natural uranium minerals.

Other isotopes of uranium may be present in smaller quantities. These include uranium-236, which forms when a U-235 atom captures a neutron but does not fission. U-236 may be in concentrations of about .4% or so. It’s not really very useful, as it does not fission easily and has a relatively low neutron cross section. With a half-life of a few million years, it’s a bit more radioactive than most other isotopes, but not radioactive enough to be considered much of a danger. If the uranium is recycled, the U-236 remains in the mix. It may be fissioned in a fast neutron reactor but otherwise is basically neither a resource nor a major problem.

Plutonium: ~1%-2%

Plutonium is formed when uranium-238 captures a neutron and rapidly decays to neptunium-239 and then plutonium-239. All reactors produce some plutonium, although breeder reactor are designed especially to do so. Plutonium-239 has a half-life of 24,000 years and is a strong alpha emitter. Comparatively speaking, plutonium is not nearly as dangerous as many other radioisotopes, including some natural ones like radium-226. However, it can be quite toxic if it is ingested or inhaled and the longer half-life means that disposing of plutonium presents concerns about the long-term stability of a site.

But there’s another way to get rid of plutonium which can turn a waste product into an asset. Plutonium is fissionable and thus can be used as reactor fuel. It can be burned in a standard lightwater reactor in the form of MOX (mixed oxide) fuel or it can be burned with even higher effeciency in a fast neutron reactor. This not only reduces material to be disposed of but increases the effeciency of the fuel cycle, possibly by up to 200 times, if all the avaliable energy is extracted by plutonium breeding and recovery.

One thing the plutonium from a standard power reactor is NOT suitable for, however is weaponry. This is because it contains too high a ratio of plutonium-240 to plutonium-239. Although plutonoum-240 is not a problem for reactors, it is a neutron emitter, which in a bomb, would cause the reaction to start too soon and the weapon to “fizzle” and fail. Weapons grade plutonium must contain at least 80% plutonium-239, but most reactor grade plutonium contains less than 70% plutonium-239. It is theoretically possible to build a weapon from reactor grade plutonium and the possibility was demonstrated by nuclear experiments in the 1970′s, however doing so requires a highly efficient weapon design, is extremely unreliable and suffers from reduced yield. In general, such material is very difficult to weaponize and would probably not be worth the effort even when compared to construction of a purpose-built weapons grade breeder reactor.

Minor Actinides: <1%

Minor Actinides are heavy elements other than uranium and plutonium which are the result of neutron capture, usually by plutonium which does not fission. They include neptunium, americium and curium. The amount present in spent fuel will vary but is higher in reactors which have high levels of plutonium. They generally have halflives of a few decades or more and are therefore somewhat hazardous, but only when highly concentrated. They are able to fission and can be used in standard thermal reactors, but they are more easily and efficiently fissioned in fast neutron reactors. In some cases, these isotopes are also useful in a concentrated form for use as a neutron source or for industrial radiation sources. Americium-241 is commonly used in industry as well as in smoke detectors. Californium isotopes such as Ca-252 are commonly used as neutron sources.

Fission Byproducts: About 3%

These are the materials which result from the actual fission of heavy element atoms. Each time a uranium or plutonium atom splits, it results in two new atoms. The new materials vary in type but tend to have an atomic mass around 80 to 100 or 130 to 150. A few of these are actually stable but most are radioactive and have varying half-lives. Fission products can be loosely categorized into three major groups:

Short-lived: The vast majority of fission products have relatively short half-lives of a year or less. These isotopes are highly radioactive and contribute to the vast majority of the radioactivity in freshly used fuel. They are quite hazardous and can can be dangerous to be exposed to even for a short period of time without shielding. However, they are not a disposal problem because of the short half life of the materials. Since the shortest lived isotopes are also the most radioactive, the spent fuel will rapidly loose most of its radioactivity and be less than 1% as radioactive after one year as it was to begin with. Simply allowing the spent fuel to decay for a period of a few years or more will eliminate these highly radioactive materials.

Medium-lived: These are the fissio n byproducts which have a half life of more than a year or two but less than centuries. These makeup about 10%-20% of the total fission byproduct yield. These can be something of a hazard, especially when highly concentrated. However, they still are long-lived enough that they require disposal of some type. Generally about 300 years is all that is needed to assure that they have been nearly eliminated from any waste material and the material is no longer any more hazardous than natural uranium ore. From a geological standpoint this is a very short period and it is not difficult to assure that a geological formation will remain stable for such periods of time.

These materials can also be destroyed by photoneutron transmutation or by bombardment with fast neutrons. However, the two isotopes which account for most of the medium-lived byproducts, strontium-90 and cesium-137, both have relatively small neutron capture cross-sections and strong binding energies. Because of this it is not generally considered to be worthwhile to transmutate these materials. When diluted and embeded into chemically inert materials, they are considered safe and will be similar to natural radioactive minerals in a relatively short period of time.

Long-Lived: These makeup about 20% of the total fission product yield and are the isotopes with half-lives of thousands or millions of years. They include technetium-99, iodine-129 and cesium-135. Because of the long half-lives they are not nearly as hazardous as other radioactive materials, but they will continue to be radioactive for a long period of time. It is important to note that they are on par with numerous natural radioactive materials such as potassium-40, which is quite common in any potassium-baring compound.

Most of these materials do have a suffecient neutron cross-section that they can be transmutation into shorter-lived isotopes by fast spectrum reactors. Therefore, irradiation of fuel by a fast spectrum reactor will have the net effect of reducing these materials, possibly by more than half. However, even without such treatment, disposal of such materials in chemically stable mediums does not present a hazard beyond that of natural radioactive minerals. Compared to uranium deposits, which contain radium-226 and polonium-210, such material is quite low in overall radiotoxicity, even in the short term. When combined with medium-lived fission products the immediate radiotoxicity is only marginally higher.

Disposal of such materials: In order to dispose of fission products which are long or medium lived, a few options exist. As mentioned, it is possible to destroy these materials and in some cases get surplus energy as a byproduct. This can be done by photoneutron transmutation, but the process has never been demonstrated on a full-scale system. Irridiation with fast neutrons of spent fuel can reduce the overall number of long-lived fission products, but because these products do not fission, a reactor with a high neutron economy is required. Even so, fast neutron irradiation is unlikely to completely eliminate fission products in spent fuel.

The most common method for disposal is in vitrified material. Vitrification is a process which produces which creates a solid, chemically inert material which is similar to a very high density glass. It is highly stable, is not easily reduced to a powder and is not soluble in water or nearly any other liquid. In general, the vitrified material is primary composed of non-radioactive materials which are used to help bind the radioisotopes. Thus, a few kilograms of radioactive material may be embedded in a cubic meter or more of vitrified material. This means that the resulting material is not as radioactive as highly concentrated radioisotopes would be. It is similar in properties to some minerals and is sometimes referred to as “synthetic rock.” Disposal of short and medium lived fission products in such a manner will result in a material which is immediately of minimal hazard and which will be equivalent in overall radioactivity to numerous natural minerals in a period of about 300 years or less. It is important to note that it will be significantly less radioactive long before this, however, than it started out as.

The case for reprocessing vs geological disposal of the entire spent fuel material:

To sum up the composition of spent fuel, this somewhat simplified graph illustrates the relative nature of the materials contained within the spent fuel assemblies:

It should be obvious that disposing of the entire assemblies is both wasteful and unnecessary. There are several methods which can be used to effectively manage the material from spent fuel in a manner which is more efficient manner.

Reprocessing - This is the most obvious solution to the waste issue. Reprocessing involves separation of the material into it’s chemical components, thus recovering the uranium and plutonium for use in fabrication of new fuel. The remaining fission products can be vitrified as waste or could potentially be used for medical or industrial isotope needs, depending on the circumstances. There are a few issues which exist with reprocessing. First, the process can be rather complicated and because of the possibility of contamination, it is necessary to have a well equipped and safe facility. This can involve an initially high investment. Also, although reprocessing does dramatically reduce high level waste, it does often produce additional intermediate level waste. This includes contaminated equipment and storage vessels. This waste is not really as much of a disposal hazard, but needs to be taken into account.

Despite the challenges, numerous examples exist of reprocessing programs which have proven to be both safe and beneficial to the overall fuel cycle. France, a nation which gets nearly all of its electricity from nuclear energy has a long-running reprocessing and isolation program which has resultes in an annual production of high density vitrified waste of about 160 cubic meters. Considering the size of the country and standard of living, this is a very reasonable and small amount of material.

The traditional method of reprocessing is aqueous reprocessing, such as the PUREX process. Although it has been successfully used for decades, newer methods, such a pyroprocessing, have demonstrated improved economics and could even be implemented onsite. Advanced reprocessing techniques can also reduce the possibility of secondary low-level waste.

Needless to say, the ecostupid movement opposes reprocessing of any kind in any circumstances.

Fast Neutron Reactors: The use of fast spectrum neutron reactors can greatly improve the effeciency of the nuclear fuel cycle as well as reduce overall waste. Fast reactors can be designed to breed fuel as fast as they burn it, thus allowing fuel rods to be used for much longer durations and thus reduce the volume of material to be processed. They can also be designed to efficiently burn plutonium and other minor actinide. Irradiation by fast neutrons can also reduce the amounts of fission products like iodine-129 and technetium-99, converting both to much shorter lived isotopes. The use of a fast neutron reactor may be part of a reprocessing program or may be used in a program that does not involve such reprocessing. Some fast reactor designs allow for many years of operation on a single fuel cartridge and produce less radioactive waste by re-irradiating the depleted materials.

Accelerator-based Transmutation: This procedure has not been demonstrated in full scale, but holds the promise of treating spent fuel in a manner which will render it safe for normal disposal and produce energy in the process. Sub-critical reactors have been proposed as a means of transmutating waste with neutrons, although this would not work with all of the isotopes present, due to the low neutron cross section of some. Another method, which would theoretically be able to address all materials present without the necessity of reprocessing and producing energy in the process is photoneutron transmutation. The company Nuclear Solutions has proposed a demonstration plant to transmutate nuclear waste using a 10MeV electron beam. Such a system would produce high energy gamma rays by secondary reactions, thus allowing for decomposition of radioactive atoms and production of surplus energy in the process.

Alternative Reactor Designs: While this would not be able to address the current spent fuel stockpiles alone, new reactor types can produce dramatically less waste and less hazardous waste. As mentioned, fast spectrum reactors can be used to destroy many of the long-lived radioisotopes, but other reactor designs can also have benefits in terms of waste produced. Higher effeciency reactors can burn the same fuel longer. This has been demonstrated by some advanced CANDU reactor designs. Thorium-cycle systems produce virtually no plutonium or other actinides and thus have much less long-lived byproducts. Spent fuel from such designs would be only need a few centuries to decay to bellow natural material levels, even without reprocessing. Other designs allow for onsite reprocessing or easier spent fuel management.

In conclusion, considering both the current technology which has been used worldwide to successfully manage spent fuel as well as new technologies which have been demonstrated or proposed, simply burying spent fuel seems both economical and ecologically foolish. Reprocessing and other methods can dramatically reduce the amount of material to be disposed of and also the total radioactivity. Burring spent fuel means one has to deal with the “worst of both worlds,” that is material which is both immediately high in radiation and which poses long-term disposal concerns. It is likely that the political reason for disposal by this method is simply opposition to nuclear energy, which would be bolstered by having additional fuel and reduced waste concerns. Of course, the Yucca Mountain plan is being protested too by the ecostupid movement, so it seems you just can’t win with them.


This entry was posted on Thursday, December 27th, 2007 at 1:06 pm and is filed under Bad Science, Enviornment, Good Science, Nuclear, Politics. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.
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76 Responses to “What is spent fuel anyway?”

  1. 1
    DV82XL Says:

    Actually, even current CANDUs have a high enough neutron economy to burn fuel discharged from light water reactors. The DUPIC cycle is a research project presently being carried out co-operatively by Canada and Korea. It provides an alternative to chemical reprocessing. DUPIC stands for Direct Use of PWR Fuel in CANDU. In DUPIC, “spent” PWR fuel is first mechanically decladded and then treated by a dry oxidation-reduction process to remove the volatile fission products. The process yields a powder, which can then be pressed into pellets again. The process does not involve chemical separation of the uranium and plutonium, and so silences the proliferation concerns. This DUPIC fuel will typically have a total fissile content of about 1.5%, so cannot be used in PWRs.

    However, the fissile content is certainly sufficient for use in CANDU, where in fact DUPIC fuel would yield about twice as much energy again as was produced in the original cycle in the PWR! The ideal synergism between CANDU and PWR: fuel is first burned in PWR, and then, instead of being thrown away, yields another two times as much energy in CANDU. Again, the total amount of spent fuel per unit of electricity is much reduced.

    Of course then it could be reprocessed and the cycle run again.


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  2. 2
    drbuzz0 Says:

    Wow. I had heard of light water spent fuel being used in CANDU reactors but the fact that you could remove fission products by a dry process like that is something I was not previously aware of. That would not eliminate the “waste” but that is still fascinating. I am aware that the CANDU reactors have a high neutron economy which could be useful for other things. They’ve done a lot of work looking into CANDU-based breeders for both uranium and thorium cycles. Facinating stuff.


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  3. 3
    Nick Says:

    Okay, so basically what you’re saying is that spent fuel is only about 1% composed of materials that isn’t either easy to deal with or can be used for something? That doesn’t make any sense. I don’t know much about this, but I do know that spent fuel has been impossible to find a solution to, so I’m calling bull**** on it being 99% not waste. That would be hard for any lobby to get burried in that form if it’s really that. If that’s the case why is the government so worried about it?

    I’d like to have somebody come up with the real numbers.


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  4. 4
    DV82XL Says:

    Nick these are the real numbers as a quick look at the subject ‘reprocessing’ in Google will show. The French, who get most of their electricity from nuclear plants have been doing it for decades.

    Doc, CANDUs can burn thorium direct once the reactor is started with uraniun.


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  5. 5
    Nick Says:

    I’m not sure if I should doubt you or not. I’ve always heard that the left over fuel from nuclear reactors was the big problem with the whole thing. That it was the type of thing that would be devistating if it got out or was somehow in the hands of terrorists and that it had to be disposed of in a manner which would insure that nobody would have contact with it for millions or billions of years.

    The way this is written makes it sound like it’s basically benign and just has a small portion of materials in it which are dangerous and that even the dangerous stuff is going to be no worse than minerals once it’s disposed of and that it’s of no concern in hundreds of years or less.

    This makes zero sense compared to everythig I have been told about nuclear energy even by the nuclear energy people who say yucca mountain is safe. They say it’s safe for millions of years to hold the nastiest most deadly stuff known to man. Then I come here and it’s “Oh it’s actually mostly not bad. It’s not that bad after a few years it’s fine. It’s just a small portion and even that portion is not that bad.”

    Please explain how these two things can possibly both be true. We did not spend a billion dollars on hollowing out a mountain to fill it with hundreds of tons of material when it’s really only a few tons that we need to get rid of. Politicians may be dumb, but not that dumb


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  6. 6
    Ashton Says:

    I would not be so quick to write off plutonium as something that we can just turn around and use as fuel. It may be possible to use it as fuel, but you should not forget that its the MOST TOXIC SUBSTANCE KNOWN TO MAN, so it’s not like you want to have it floating around like it’s no big deal. Aside from the fact that any reactor you put it in just makes more plutonium AND the fact that it’s not anything like anything natural. Yeah, I know natural does not mean non-toxic and there can be toxic stuff in nature but let me repeat: MOST TOXIC SUBSTANCE KNOWN TO MAN


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  7. 7
    DV82XL Says:

    Nick, Ashton – the short answer to both of your comments is that you have been sold a package of lies.

    Nick, it really doesn’t matter how much money was spent in the U.S. on the Yucca Mountain repository, it isn’t needed. The U.S. is not the only country that uses nuclear power, the U.K. and France, among others have been at it for years and they also have been reprocessing for years. This is just a simple mater of fact, that you can confirm in a few seconds with Google.

    The politics of reprocessing in the States have been caught up in the dream of ridding the world of nuclear weapons, not because you can produce weapon grade Pu from spent reactor fuel, but because the technology is the same one that is used to get that grade from the discharge from breeder reactors.

    Ashton – Pu is not the ‘MOST TOXIC SUBSTANCE KNOWN TO MAN,’ there are many, many compounds that are deadly in much smaller amounts, tetanus, botulinal, shigella neurotoxins are deadly at 1 nanogram/kg in humans.

    During the Manhattan Project in 1944 and 1945, 26 men accidentally ingested plutonium in quantities that far exceeded what is now considered to be a lethal dose. Since there has been a consistent interest in the health effects of this exposure and these men were closely tracked for medical studies. As of 1987, more than four decades later, only four of the workers had died and only one death was caused by cancer. The expected number of deaths in a random sample of men the age of those in the group is 10. The expected number of deaths from cancer in a similar group is between two and three. Thus at least 22 men have been able to live more than 40 years after ingesting “the most toxic substance known to man”. The fact is from a purely chemical standpoint, it is about as poisonous as lead and other heavy metals.


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  8. 8
    Ashton Says:

    Why don’t you tell that to the family of that defected spy in London who was poisoned by less than a milligram of plutonium?


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  9. 9
    drbuzz0 Says:

    That’s POLUNIUM, not PLUTONIUM. Plolunium-210 is highly radioactive per a given quantity. It is way more radioactive than plutonium-239 or even plutonium-240.

    This is because it has a shorter halflife. It is only 138 days so in 138 days a gram of polonium will have half decayed and thus released a lot of energy. Pu-239 is 24,000 years and hence in a given amount of time there is much less radiation.

    This illustrates an important point too: Shorter halflives mean more radioactive. This is important because although spent fuel does contain stuff that could literally kill you from a few feet away, it will be gone in a very short period of time. The most radioactive isotopes decay very rapidly. Hence, it looses more than 99% of the radioactivity in the first year or less. Isotopes with longer halflives may be a longer term concern, but they’re far less dangerous and potent.


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  10. 10
    Dave G Says:

    How in the hell does reprocessing pose a weapons proliferation concern in the United States or other members of the “Nuclear club.” I can understand why one might get nervous about iran or libya building plants that could make weapons grade plutonium, but who the hell thinks it’s gona change anything if the US or Brittan has reprocessing? I mean they both have gobs of weapons materials and have for years. Both have thousands of warheads to begin with. It doesn’t add anything!


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  11. 11
    DV82XL Says:

    As best as I can understand it, the argument turns around so called ‘dual-use’ technology. Reprocessing is in fact just such a technology, as in its most common form Pu is separated from the spent fuel. While as Doc pointed out, reactor grade Pu is not suitable for weapons, irradiated fuel form a dedicated breeding cycle is, and can be separated in the same plants.

    The hope was that by stopping all reprocessing internationally the spread of nuclear weapons would stop, and the stockpile of weapons-grade Pu decayed actually reverse. The theoretical possibility was enough to drive their thinking to the conclusion that all stocks of separated plutonium had to be eliminated.
    Carter attempted to set an example for the rest of the world and got the IAEA and others to buy into the idea, but the rest of the world reprocesses. Currently, the United Kingdom is the world’s leading reprocessing contractor. Even Japan has to transport highly radioactive materials for reprocessing to England. If the U.S. had appropriate facilities to handle this waste, it could narrow the chances of a waste transport disaster. Many nuclear plants, including Minnesota’s Prairie Island plant, are already equipped to handle reprocessing.
    In addition, other nations have developed alternate, safer means of reprocessing, and let’s not forget that reprocessing is cost-effective. Americans have to keep in mind that just because they stopped developing nuclear energy after Three-Mile Island doesn’t mean the rest of us stopped too. The grim fact of the matter is that the U.S. may have more working reactors than any other country; in terms of technical development you are no longer leading the pack.

    I don’t write this with any sense of joy or anti-American triumphalism; you should be in the forefront and why you are not is a great tragedy.


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  12. 12
    drbuzz0 Says:

    US energy policy is important to EVERYONE. First off, the US uses HUGE amounts of energy and how the US gets that energy effects the atmosphere and the climate that EVERYONE shares. It is in the best interest of the world to have a country that is so energy hungry go with the cleanest methods avaliable.

    Furthermore, the US is the one remaining superpower and is in a position to be both a trend-setter and a developer of nuclear technologies. Considering how much money the DOE spends and how much has been spent on nuclear technologies (both peaceful and weapons) in the past, the US has the resources to start building reactors. What do we expect? India or China or some other country to carry the burden of developing new systems? They are still technically third world countries.

    Right now, India is making strides in nuclear technologies and looking at thorium fuel and reprocessing options. Canada has taken heavy water systems to a whole new level and shown some amazing potential with CANDU based systems. France is developing new technologies and Russia is working on turnkey nuclear reactors in modular systems.

    Nothing against these countries, they need to be thanked for their contributions. But the US sent men to the moon! We have some of the best National Laboratories in the world. We’re the biggest single economey in the world (at least for now) and likes to think of itself as a trend setter and a big achiever. This embarrassing.

    BTW: What does canada do with its waste?

    And DV82XL, if I remember correctly don’t you live in eastern canada? If you want a good reason to care about US energy policy it’s called “The Prevailing Southwesterlies.” In other words, what the US does to fufill energy needs ends up in your lungs


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  13. 13
    DV82XL Says:

    Oh I care alright, and for all of the reasons you state, and yes I live in Montreal, Quebec, but it’s the acid rain that impacts our Northern Lakes and forests that is the most concern.

    Used CANDU fuel is first cooled in used fuel pools and then transfered to dry storage. Its final disposition is in the hands of the Canadian Nuclear Waste Management Organization who has adopted a plan called The Adaptive Phased Management Strategy. This plan is designed not to shut any doors; thus in the medium term it will use a shallow repository where the spent fuel will centrally stored while a decision on reprocessing is made.

    Reprocessing is at this point and with currently available processes not economically for used HPHW fuel because this type of reactor burns the fuel down more than LWRs. That and as one of the major uranium producers there is no economic or energy security reasons to at this point, but we are not stupid enough to think that all this might change in time thus we are keeping our options open.

    Even so we are also planning a deep repository somewhere in the Canadian Shield (possibly here in Quebec) which is one of the most geologically stable formations on the planet, but again current plans will still make the material in this repository accessible at latter date if it is needed.

    The used fuel owners are responsible for the costs. The Nuclear Fuel Waste Act requires them to contribute annually to trust funds to ensure that the NWMO has the money necessary to implement this approach.

    Similar plans have recently been approved in the UK and France and are already well advanced in other European countries such as Finland and Sweden.

    BTW, India uses CANDUs, although they build them themselves now.


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  14. 14
    drbuzz0 Says:

    Interesting. If the politicians could ever come to some kind of consensus and enact a comprehensive energy policy then I think Canada and the US would be excellent partners in nuclear energy and reprocessing. We already share much of the same energy through the grid connections between the countries and have a history of joint projects (The Alaska highway, NORAD).

    The US has very extensive facilities left over from the Cold War and a very capable National Laboratory system. The US also has done a lot of reprocessing and materials extraction in the past as well as enrichment. Canada has extensive experience with HPHW reactor systems and also has done (as you mention) a lot of good work recently in terms of extending the technology of fuel reprocessing and LWR -> HWR fuel systems.

    Canada has done some great work at Chalk River with modular reactor designs and fuel cycles. The US has more than a few light water reactors, but it could use more nuclear energy and Canada has done well marketing the CANDU elsewhere.

    If the two countries pooled their resources, it could turn out to both financially and environmentally rewarding. The technologies which both countries have are very complimentary.

    But then again, a nuclear-oriented energy policy? HA! That ain’t happening anywhere round here any time soon.

    Oh also, I used to live in up state New York. Amazing lakes… but too many of them in the Adirondacks are dead. I remember spending part of the summer with a friend at his uncle’s lakehouse near Saranac Lake. Fishing you could only hope to catch Bullhead, a species of fish which was tolerant of the acidic lake. Not especially good eatin and nasty little bastards (they’d lie there and make you think they’re dead and then grab your finger with razor sharp teeth). His uncle had a big trout mounted over the fireplace. It was caught in the 1960′s or so. Those are long gone. They can’t tolerate the water now, except for in some of the less acidic lakes… which are fewer and further between than ever before.


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  15. 15
    DV82XL Says:

    Doc,

    It would be great if we had a bilateral nuclear power agreement, but it’s not likely to happen. A bit of research will show why.

    At some level the dual-use critics are right; nuclear power has been used as a fig-leaf for nuclear weapons programs. Light water reactors must use enriched fuel; enriched uranium is also needed for gun-type A-bombs, and to fuel the breeders that make weapons-grade plutonium. Heavy water reactors use natural uranium unenriched, just refined from yellowcake.

    The people that want nuclear weapons have always understood that they were very vulnerable if their programs weren’t tied to power generation. Great Britain, despite the fact that they were involved in some of the early work on HPHW reactors moved away from the design because they had decided to build weapons.

    The other big problem is coal. Canada has an active nuclear industry for the simple reason that the uranium mining sector is bigger and more politically connected than coal is.

    Coal has been pushing an antinuclear agenda for decades. In Australia and Germany they have dropped any pretense and have lobbied publicly against nuclear power claiming would cost jobs and thus devastate the economy.

    Coal has been active in the antinuclear lobby as well in the U.S. Several times power utilities in some U.S/Canada border State has floated the idea of financing a CANDU facility north of the border and buying all of its output for resale, and in all of these cases the idea was killed and coal burners built instead.

    This is not to say that CANDUs are the be-all-and-end-all of reactor design. In the end we are going to have to go to molten a salt type that much is clear. Meanwhile HPHW reactors will never be licensed in the U.S. and PWRs will never be certified in Canada for political reasons alone.


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  16. 16
    drbuzz0 Says:

    Agreed to some degree, DV, but lets face a couple things: First of all, 3% enriched uranium is about as useful for making a weapon as unenriched. Giving access to low-level enriched stuff to Canada is not going to mean there’s going to be a Canadian nuclear weapons program any more than natural uranium is. In either case you’d have to do almost as much enrichment anyway.

    Also, you don’t need enriched uranium to produce plutonium. Yes, it helps but it can be done with fast cycling of breeder material through a HWR or even a graphite core reactor. Hell, that’s how we did it for a good part of the cold war. This proliferation bull is nonsense. Canada is not going to become a nuclear superpower because of the US allowing it to have access to enrichment facilities.

    And no, the CANDU is not the be-all-end-all. I agree to a point on molten salt reactors being a good long term solution, but that’s only part of it. I’ve seen a lot of development on a bunch of fronts for fast spectrum reactors and modular contained reactors for smaller energy needs… but I could write a whole post on that.

    Point being: Canada has some very productive uranium mines. The US has a few too, but most uranium is imported since many of the mines in Colorado are now closed. Canada has excellent experience with HPHW reactors. The US has enrichment facilities. The US has experience with PWR’s and BWR’s and Canada has developed some excellent materials handling methods and peak-demand reactor dynamics.

    The two nations can compliment each other nicely. The combination of enriched fuels and fuel cycles which allow for the higher effeciency of CANDU’s can mean more energy from the same fuel. The use of Canadian uranium mines and US Enrichment plants is mutually beneficial. Adding CANDU reactors to existing plants in the US with PWR systems would allow for more efficient use of materials onsite.

    The resources and facilities of both nations, if put together would be a big win-win. Also, the US needs to consider that if it wants to prevent other countries from building enrichment facilities that could be used to make weapons, then the US really has a responsibility to be more open with providing low-level non-weapons-grade material to the international market and taking a more active roll in promoting peaceful nuclear energy.

    As for the coal lobby? I’ve got nothing against coal miners and don’t delight in anyone loosing their job. But I also have nothing against asbestos workers and don’t have a problem with that industry having dried up. Best plan for the country and the world is not always going to be the best for a special group, especially in the short run. Anyway, I wonder if it’s really the individual workers anyway. I think most of them would be secure enough in the short term to consider early retirement or other alternatives even if reactors started being built now.

    In the end, the coal lobby can only do so much. No amount of money can buy a politician if the electorate refuses to support a policy. Then they’re out of a job. The point is that coal is not only greasing pockets, the dual of coal advertising and anti-nuclear groups is working to keep people malinformed and thus allowing the politicians to ride on public ignorance. That is why I make posts like this. At least *someone* is doing*something* to pull in the other direction. Course… more always needed


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  17. 17
    Spidey Says:

    Working together on nuclear energy is long overdue. The United States has the funds and resources to do a lot, which has been pointed out. The US absolutely should pool it’s knowledge and resources with Canada and work together toward more nuclear energy.

    But not just canada. It’s logical that those two neighbors would have a common interest in sharing their technologies and working together, but also other countries. France, South Korea, Japan: Basically the whole world. It’s about damned time! Global warming and energy is a worldwide problem. And if enough countries jump on the bandwagon of clean and safe nuclear energy then it will help getting those like Germany to start to see the light.

    I also think that having international cooperation in the energy sector is key to keeping proliferation in check, but that’s just me.


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  18. 18
    Sarah Says:

    What a fantastic idea! Sharing research and joint programs like mentioned are a good way of promoting international coopration and unity. That seems to be something that the world has way to little of and which the US under Bush has not been working toward. The US should extend a hand to Canada and to other countries. What about Latin America? I don’t know that Latin American countries have the funds to really contribute to nuclear research but they could benifit from US and Canadian lead promotion of nuclear energy. There’s nobody in the Americas who is really working on bringing Latin America into the world of better energy. And as you say, we all breathe the same air.


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  19. 19
    DV82XL Says:

    Some quick remarks on the above comments

    -Actually we have sold CANDUs in South America, Argentina has three. It might surprise some that Brazil has two nuclear reactors, a third under construction, and is developing a more efficient enrichment technology. Canada has close nuclear ties with South Korea, and relations are thawing with our old partner India. (we split up after the Indians tested their first nuclear weapon).

    -Everyone should understand that building reactors is a cutthroat business, as is everything else in the energy sector and this will always stand in the way of full cooperation.

    -Canada already supplies the U.S. with most of its uranium , and will continue to do so regardless of the types of reactors used.

    -The Global Nuclear Energy Partnership’s (GNEP) is a program that is supposed to manage the transfer of nuclear energy technology around the world. It envisions fuel being leased to the users while still remaining under the control of the producing nation.

    -Canada, like Japan is fully capable of making a nuclear weapon without outside help and well within a twelve month time frame, and like Japan we simply chose not to.

    -For a more complete treatment of the role of coal in opposing nuclear, I refer you to the Smoking Gun entries at Rod Adams’ Atomic Insights Blog


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  20. 20
    drbuzz0 Says:

    DV8: Quick comment on the “cutthroat business” of nuclear energy and every energy product. I’m all for capitalism, but there comes a time when you have to separate the two basic sides of energy:

    A) The pure profit end of it, which is driven by whatever is cheapest and provides the most energy for a given situation.

    B) The enviornmental and long-term side. This is where the government needs to step in and make regulations for what can and can’t be done. If not, everyone would just be burning dirty coal with no scrubbers because it’s cheapest. Subsidies are okay, when done properly. They exist for a reason: To encourage development of things which market forces alone would not produce.

    If there really were a comprehensive nuclear energy initiative, spearheaded by the US and/or Canada then there would be more reactors being built than either nation could supply on its own anyway. What it comes down to is mutually beneficial plans which are based on a good combination of business interests and government pushing things in the right direction. There’s no reason why a good stragigy could not get things going in the right direction.

    I’m not sure how many are aware of the GNEP, but in my opinion, they have not really done enough and could be helped a lot by a country like the US playing a much bigger role.

    In the end I have to wonder how much of nuclear energy can rely on profit, with the law the way it is. Right now, it’s too expensive to get units approved. And you also need to look at the players: General electric and Westinghouse in the United States, for example. GE can sell reactors but they also make wind turbines and coal boilers. Where’s the bigger profit for them? Sell a reactor every decade and spend millions on the aproval for the design and implimentation, or crank out wind turbines and sell each for a few mill. Sure, the wind turbines don’t do squat for the enviornment, but with all the tax breaks and incentives they get and all the demand they can rake it in. And on top of the selling gas turbines and coal equipment and such: Much less reglatory headache.

    That’s not to say I don;t think reactors can be profitable, they can, but to make them more enticing than selling something else, things need to change.


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  21. 21
    Dave G Says:

    Quick comment: I agree with both Buzz and DV to some point on this. It’s something which is not going to happen with the current system. It’s technically possible. It would benefit both nations and other nations, but DV is right about the interests here.

    What drbuzz0 is proposing would require the nations involved to basically sit down and say “We’re going to implement a pro-nuclear policy which will involve international cooperation to create a nuclear-based energy strategy.” At that point it becomes a question of how? Better nuclear licencing practices, higher air pollution standards, comprehensive waste management strategies, industry-government programs, maybe even subsidies. This would be done with the priority being to impliment nuclear energy and profitability is still possible.

    Yes, you could do this. Nationsl cooperate on big projects and make private interests a secondary matter all the time when there is a war or some other impending problem. WWII, is an example. The government had companies in the US and Canada and Brittan building stuff. They even licended aircraft designs to the soviets. Why? Because they had to. They did it because it was their neck on the line. You have that sort of situation and all of a sudden penny hording takes a back seat to getting the job done.

    I believe that energy and global warming and pollution are every bit as big a threat as a world war and if the government treated it like they did with the cold war or the second world war or the Marshall plan we could lick it. You gave norad as an example of the us and Canada working on the same thing. Why did they? Simple. Soviet missiles were a threat to both and both needed to have a defense system as quickly and effectively as possible. The USAF and the Canadian forces didn’t grumble over who gets control of what because their neck was on the line.

    Problem is: nobody thinks their neck is on the lne.


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  22. 22
    DV82XL Says:

    You are so right when you say there would be more reactors being built than either nation could supply on its own anyway if we didn’t have our collective heads shoved up our behinds.

    People, the framework is in place: The Global Nuclear Energy Partnership is an American program administered by your own DOE which Canada along with China, France, Japan, Russia and fifteen other countries have signed on as partners.

    All that needs to be done is make it work.


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  23. 23
    Lizzza Says:

    I know I’m not going to talk any sense into any1 here, but u really should look at the friends of the earth page because they explain how all this spent fuel is a lot worse than the lies here. U should realize that everyone who actually cares about the planet knows that nuclear is the worst thing you can do and even worse than coal.

    If U don’t believe me u can ask friends of earth or greenpeace because both of those are ppl whose lives are to defend and help earth. I look here and I see ppl who want nuclear and its obvious u want to destroy bc that is what nuclear means. it is destruction. U talk before about destroying tissue. that’s what nuclear is all about. U see cancer and want to fix the problem and so instead of making it better u say “Oh lets destroy the tissue and make the problem go away.” it’s like nuclear is “Oh we won’t get along with this country so we’ll destroy it and make the problem go away”

    That’s the nuclear way is to destroy. To destroy countries and bodies and the enviornment. Destroying a problem does not mean solving it. U need to realize that just bc u destroy the problem only gets worse

    u need to stop being so tough and trying to do things u kno r evil because u cant admit what is right and dont want to look wimpy. It won’t matter when nuclear has killed us all!


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  24. 24
    Paul Says:

    Lizza: Stop. Sniffing. Glue.


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  25. 25
    DV82XL Says:

    Lezza dear I am a trained chemist that has worked full time in my field for over thirty-five years after spending a a long time in school training to be what I am. I know that my knowledge in these matters is correct because the work that I have done for the people that were paying me turned out the way I predicted, and they expected. In other words long experience in the real world making things happen the way I want in this field pretty well has established that I know what I am talking about. I have a career full of proof that my understanding of these things are correct.

    What I would like to know from you is given that you have no training in these matters, by what massive amount of arrogant hubris do you believe you are qualified to hold an opinion about this? How do you judge that what I and other educated scientists know is inferior to the ravings of some non-scientist vomiting bull**** on the web while at the same time begging you to give them funds? Have you checked their qualifications? Read their peer-reviewed publications? Taken the time to check their figures and sources?

    No you haven’t

    I will tell you something, when some company is spending a very large sum of money, when peoples jobs are on the line if they aren’t right – opinion – anyones opinion is checked, rechecked and verified. That is the way we work because we have no other choice. Now you might like to believe that the world works in a certain way, but I don’t have that luxury – and you should get down on your knees in thanks that I don’t. Because every time you turn a tap and water flows; flick a switch a get light; wear textiles, and eat food, it is because someone like me knows how the universe works and makes it give you what you need.

    Wake up Lezza, just wake up


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  26. 26
    Paul Says:

    DV82XL, agreed 100% and I have a lot of respect for your profession and all the education you have. However, I don’t think it’s necessary for someone to be a professional chemist or scientist to understand the basics and realize where the information comes from.

    It’s the mindset that matters: know where to get the info; know the people who know their stuff; know the basics; be a critical thinker.

    People like Lizzza don’t have a problem with not being knowledgeable, because you can’t reasonably expect everyone to be a professional. The problem is that people *think* they know more than the pros when they don’t. I am a student, and I’ll admit that my knowledge of chemistry is far far less than yours. But that’s the point. I’ll admit it. If I am unsure of something and I need info, I’ll go to someone like you, who I know has the background. Or, I’ll open a book.

    The point being, I don’t go to places like greenpeace which have an extremist agenda. And more importantly, I’ll take things critically. If a professional chemist says something to me that doesn’t seem to make sense or sounds politically motivated I will get a second opinion. Not because I don’t trust the knowledge of a professional in the field, but because I understand the importance of not allowing any one source to dictate to you how things are.

    That’s the problem here. Lizzza does not need to go to graduate school to figure this out. She’d need to do so if she wanted to know all the ins and outs of nuclear energy and ecology. But to understand the basics all she would need to do is hit up a few good internet pages and check a book or two out of the library. That’s reasonable to expect from a citizen before they go and start spouting opinions and casting votes with no real info!


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  27. 27
    Dave G Says:

    Paul: Pretty much what I was thinking. I’m not in the field of chemistry or nuclear energy, but if I need answers, I’ll ask DV82XL and not Lizzza, and in the past he (I assume DV82XL is male, sorry if not) has provided good answers to questions. These answers were based on science and with reasonable explanations. In my book, that’s what matters. And yes, I am going to check sources for any information that comes out politically or that seems doubtful.

    But as far as the career of proof, I don’t think I have any need to have DV82XL “prove” he knows what he is talking about. I can usually smell a rat from a distance, and everything he says is totally reasonable and fact based. Lizzza I smelled from across the room though!


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  28. 28
    Paul Says:

    Getting a bit back on topic there is something that I think needs to be emphasized more strongly. There are some natural radioactive materials which are very dangerous and toxic. Radium is horribly toxic and very very radioactive. It has a half life that is long enough to be a problem to get rid of but it’s also very easy to ingest and it has bad decay products. It’s found in uranium ore, but it’s only a big problem when it has been extracted and concentrated from tons and tons of ore. Then it’s dangerous as hell and much worse so than plutonium. The point is that these materials are out there and the reason its not a huge deal is that they are embeded in large amounts of minerals and ore. That is a good example of how you can do the same with waste materials if you dilute them and use good material.


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  29. 29
    Ashton Says:

    Do I need to remind everyone that this is the same website which has stated (repeatedly) that depleted uranium is basically harmless or “On par with standard lead bullets in terms of human toxicity.” If you want to start talking about questioning the reliability of your sources then I think that’s probably something you might want to consider, especially when depleted uranium has been noted as violating the Geneva convention for being cruel and exposing civilians to toxic and deadly substances and and has been shown to be responsible for a huge rise in cancer in the civilian population where it is used. I don’t know what kind of agenda is here, but when you start talking about irradiating Iraqi children and saying it’s nothing at all, then I have my questions. And so what if plutonium is not the deadliest substance known to man? it’s still one of the most deadly, even if you can name a few which are a bit worse.


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  30. 30
    DV82XL Says:

    Paul and Dave, yes my reply to our Lezza was very much an ad hominem appeal to authority, and yes I recognize that it is broadly invalid; I was making the point that if you choose to go this route, you best check the credentials of your source.

    Ashton, Your understanding of these matters is no more complete than Lezza’s is, although you can state your case a bit more clearly.

    There are many elemental metals used industrially that are much, much worse than Pu and U-238. Cadmium and Beryllium spring to mind as examples. Both are used in large amounts in aerospace, both in commercial and military aircraft. Both of these materials will harm you much faster than the two you fear. Frankly, I would ingest ten grams of Pu or U-238 long before I would take one gram of Cd or Be. The industry knows these are bad and has been working hard for over a decade to reduce there use – without the help of jabbering demagogs from the cheap seats.

    The histrionics about Pu and U-238 have nothing to do with science and everything to do with politics, the chemistry, physics, and epidemiology just doesn’t support these fantastical contentions. And again, you have to look beyond how you want the universe to work and look at the way it does, and understand that we cannot run a society that is dependent on science and technology on uninformed fears.

    The truth is quite accessible, if you are willing to take the time to broaden your understanding of the fundamentals. In the end you owe it to yourself to do so, otherwise you are left doing exactly what Paul and Dave are properly accusing me of; depending on the self stated authority of the source, instead of an understanding of the facts.


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  31. 31
    Paul Says:

    Sorry if it came off like nitpicking. Appeal to authority is a fallacy if you take what an authority says at face value no matter what, but I think you have shown that you can back yourself up with the facts and that is what matters. Either way it’s better than an apeal to a non-authority any day.


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  32. 32
    Finky Says:

    One of the best posts I’ve seen here. This is some great information that I’ve never actually seen presented in such a concise and easy to understand way. Looking at it, I am amazed that there is not more info on what exactly composes this stuff called “Spent fuel” which people seem to look on like it’s some sort of black magic. Enlightening to say the least!


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  33. 33
    Fat Man Says:

    I would be very interested if you could point me to a graph showing radioactivity vs time for used lwr fuel elements.


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  34. 34
    DV82XL Says:

    Here you go:

    Decay Activity of Spent PWR Fuel

    Drops rather quickly, doesn’t it?


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  35. 35
    drbuzz0 Says:

    Remember as listed above: Most fission byproducts are “short lived” by which is meant that the half-life is months or less, so they’ll be about gone in a couple of years. Also, the short activity means they are by far the most radioactive. Thus, when the fuel comes out of the reactor, the vast majority of the radiation is from these short-lived nucleotides which decay very quickly.

    IIRC, after about 6 or 7 years, better than 90% of the gamma radiation from spent fuel is from cs-137, which is the most common gamma emitter amongst the “medium-lived” byproducts. It has a half-life of about 30 years. And of course, the “long lived” fission byproducts are, by comparison, not all that radioactive at all. Comparably speaking, technetium-99 or iodine-129 are not all that “hot”


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  36. 36
    Crinkles Says:

    This is nothing but a load of lies. You are spreading a lot of stuff that is so stupid and so obviously false that nobody is going to fall for it. The 1% that is going to have to be gotten rid of is more than enough to kill every person on then earth. It won’t though and that’s what you are counting on. It won’t kill them outright all at once but it will make people suffer for generations. It will be a burden on the children or children’s children. You’re not getting anyone into buying this. You have no right to pass this on to others or to the earth.


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  37. 37
    DV82XL Says:

    Actually we’re counting on burning it up in accelerators. The plan is to use particle accelerators to transmute high level nuclear waste into new elements with shorter half-lives or nonradioactive elements.

    During transmutation a particle accelerator is used to provide speed, and therefore energy to proton particles. When this beam of high-speed protons hits its target, usually lead or bismuth, it knocks out large numbers of neutrons which, because of the transfer of kinetic energy, will also be moving at high speeds. In order to be of use to transmutation, a moderator of heavy water slows these neutrons down. Once moving at slow enough speeds, the neutrons can be absorbed by the waste products.

    This causes the waste to change from an unstable to an element with a shorter half life or, as is the case when highly radioactive technetium 99 changes to ruthenium 100, a nonradioactive element. With enough neutrons present, the transmutation process can take place quickly and new waste can be cycled in as the successfully transmuted waste is cycled out ready for the final step. It can then be removed and disposed of safely without risk of radiation contaminating the environment.

    So we can deal with that 1% that can’t be used.

    What we can’t deal with is people like you that make accusations about our motivations from a position of total ignorance.


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  38. 38
    Philip Thomas Says:

    New reader to this blog and, as a fellow scientist, I’m already a fan. I’m trying to learn more about Nuclear power but I’m increasingly baffled by the different types of power plants you speak of, e.g. heavy vs light water. If you’ve a blog post that discusses the key types then I’d appreciate a link to it. I’ll check other sources in the mean time but I find your writing tends to be more level-headed and accessible than most.

    Sorry that you have to take so much flak off people like Lisa and Ashton. As an ecologist, I get the same from people about evolution. It doesn’t matter how carefully you explain things, how much you point out what we know, knowledge hard won over decades by legions of scientists, there comes the simple refutation of “well, I don’t believe that”. I’m surprised you keep so calm; I get ****ing infuriated.


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  39. 39
    DV82XL Says:

    Philip a good source for information on the different reactor types is the Nuclear reactor technology page at Wikipedia.

    While I wouldn’t rely on that source for all things nuclear, that entry is relativity unbiased and accurate. (as of today) A good place to start.


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  40. 40
    Soylent Says:

    “The 1% that is going to have to be gotten rid of is more than enough to kill every person on then earth.”

    The chlorine gas we produce every year is enough to kill every living human about 100 times over. This is simply not a reason for concern.

    Some 10 000-30 000 people die every year due to coal power in the US alone acording to studies conducted by the EPA and other institutions. Apart from a handful of mining and construction accidents a total of less than one person can credibly be attributed to the operation of civilian nuclear power in the US. That blood is on your hands.


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  41. 41
    Soylent Says:

    “Apart from a handful of mining and construction accidents a total of less than one person can credibly be attributed to the operation of civilian nuclear power in the US. That blood is on your hands.”

    (Clarification: I was refering to the deaths incurred by the coal power nescessry as a result of obstruction of new nuclear power.)


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  42. 42
    George Carty Says:

    Didn’t the United States stop reprocessing spent fuel because Israel’s first atomic bomb was made using stolen US plutonium?


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  43. 43
    Soylent Says:

    No, I don’t think so.

    As far as I know Israel used indigenous uranium supplies from phosphate deposits and produced plutonium from unenriched uranium fuel in their heavy water moderated reactor in Dimona that has been online since some time in the 60′s. They may or may not have received significant technical help from the french but they were certainly talking to each other.

    The US stopped their policy of reprocessing following the Indian nuclear test in 1974, but I don’t think it was the primary reason for it. It turned out that uranium was not anywhere near as rare as it had been first assumed, the growth rate of nuclear energy lower than expected and reprocessing technology turned out to not be cost competitive with just mining more natural uranium. If you don’t believe reprocessing is all that useful(yet) you don’t want to give other countries that do not yet have nuclear weapons a plausible excuse for enriching plutonium.

    To get high quality plutonium(from a weapons perspective) it’s necessary to keep the burn up low, and that means taking the fuel out of the reactor much earlier than one would expect from a civilian nuclear reactor; but this is not as easy to keep track of. The kind of plutonium you get out of reprocessing spent fuel with high burn up has a large fraction of plutonium-240, which undergoes spontaneous fission which releases neutrons. If you have too many stray neutrons in a nuclear weapon it will blow itself apart before it becomes fully imploded, giving a fizzle instead of a proper nuclear explosion. There’s also a sizable fraction of plutonium 241 in fuel with high burn-up; this releases a lot of heat(possibly a very bad idea to insulate it with a feet thick layer of high-explosives) and makes the material far more dangerous to handle.

    India appears to have produced its plutonium in the 40 MW CIRUS reactor, purchased from Canada and supplied with heavy water moderator from the US using uranium mined and processed into fuel elements in India. There were arrangement made for inspections and India refused to sign the NPT, so it wasn’t illegal for them to do this per se; but it was not well received.


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  44. 44
    Soylent Says:

    Pardon, that should say: There were NO arrangement made for inspections…


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  45. 45
    DV82XL Says:

            Soylent said:

    India appears to have produced its plutonium in the 40 MW CIRUS reactor, purchased from Canada and supplied with heavy water moderator from the US using uranium mined and processed into fuel elements in India. There were arrangement made for inspections and India refused to sign the NPT, so it wasn’t illegal for them to do this per se; but it was not well received.

    I believe that in the end, the core was fueled by uranium supplied by the United Kingdom. The reactor was built before there were international safeguards. The only thing was a secret clause in the agreement with Canada that the reactor wouldn’t be used for weapons production.

    The source of the highly enriched uranium that was irradiated to make the weapon grade plutonium is somewhat obscure, India has encouraged the belief that it was all made from Indian uranium at the Rattehalli enrichment plant, but has never confirmed this story, leading to the suspicion that some of it was obtained illegally or from diverted material that was obtained under a no weapons contract.


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  46. 46
    Soylent Says:

    Thank you, I wasn’t aware of that.


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  47. 47
    Justin Wright Says:

    Wow, that is totally cool. I had no idea there was so much involved in the by-products of nuclear power.

    JT
    http://www.Ultimate-Anonymity.com


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  48. 48
    norrin radd Says:

    I have no reason to doubt your expertise on this subject, and I will state flat out that I know next to nothing of it.

    However, several times you mention the coal lobby, which I think raises a very legitimate question-
    who signs your paycheck? By that , I mean, are you employed by a manufacturer or builder of nuclear plants, or a nuclear utility? If you work for a university, does the grant money paying for your research originate from an industry that has a financial interest in the expansion of nuclear power?

    Finally, I take issue with your use of terms such as “ecostupid” and your apparent demand that we “appeal to authority” and presumably accept the result at face value without further investigation. I’d like to point out that many people were around to see rivers catch fire due to chemical pollution, the near meltdown of Three Mile Island, Chernobyl… if people are concerned about accepting promises of corporations with profit at stake, it’s with good reason. It does NOT make them “stupid”. I’d say it makes them smart enough to proceed with caution.

    I have no “extreme agenda” here, nor am I dogmatically opposed to the use of nuclear energy. Indeed, I think we have little choice but to make good, informed use of it I simply have a desire to know more, and to get assurances that corporate interests are not blowing smoke up our collective asses once again so they can profit while the rest of us clean up the mess left behind.


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  49. 49
    norrin radd Says:

            norrin radd said:

    I have no reason to doubt your expertise on this subject,

    Wait – I just read your bio, which states:
    “Though educated in IT and computer science, I’ve long been an advocate of the thrills of amateur science, experimentation and discovery.”

    So I take back my comment about not having reason to doubt your expertise on the subject. Now I have plenty of doubts. As it turns out, your statement above also applies to me. Dies that mean that I, too, can declare myself an expert on nuclear physics?


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  50. 50
    Poul-Henning Kamp Says:

    Just a short note on Pu-240 as weapons material.

    It is absolutely true that Pu-240 is a lousy material for building a military grade nuclear weapon, it will have unpredictable yield, lifetime uncertainty and many more problems that would make it a non-starter.

    This is a much repeated truth, unfortunately, people usually forget to explore the space around this absolute statement, but once you check things out you find the disturbing fact that the very reasons that make Pu-240 useless in a military setting, make it a near perfect material for terror weapons.

    One of the really hard things about a nuclear implosion weapon is getting the necessary neutrons at the right moment to start the chain reaction, with Pu-240 you don’t have that problem, making it a lot easier to get an explosion.

    It may not be 100 kt or even 20kt, but your average terrorist would be tickled pink by the thought of even 1 kt yield, and if the resulting mess is radioactive, he won’t mind if all he getsout of it is 72 sweet raisins.

    Credible sources claim that even if you just drop one slightly subcritical Pu-240 on top of another, for instance in a penthouse apartment, you will, apart from dying pretty instantly, have made for a really really lousy day at the DHS.

    So don’t underestimate Pu-240, just because DoE cannot use it, doesn’t mean you should leave it lying around.

    Similar concerns exist for other actinides.

    /phk


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  51. 51
    DV82XL Says:

            norrin radd said:

    I have no reason to doubt your expertise on this subject, and I will state flat out that I know next to nothing of it.

    However, several times you mention the coal lobby, which I think raises a very legitimate question-
    who signs your paycheck? By that , I mean, are you employed by a manufacturer or builder of nuclear plants, or a nuclear utility? If you work for a university, does the grant money paying for your research originate from an industry that has a financial interest in the expansion of nuclear power?

    Finally, I take issue with your use of terms such as “ecostupid” and your apparent demand that we “appeal to authority” and presumably accept the result at face value without further investigation. I’d like to point out that many people were around to see rivers catch fire due to chemical pollution, the near meltdown of Three Mile Island, Chernobyl… if people are concerned about accepting promises of corporations with profit at stake, it’s with good reason. It does NOT make them “stupid”. I’d say it makes them smart enough to proceed with caution.

    I have no “extreme agenda” here, nor am I dogmatically opposed to the use of nuclear energy. Indeed, I think we have little choice but to make good, informed use of it I simply have a desire to know more, and to get assurances that corporate interests are not blowing smoke up our collective asses once again so they can profit while the rest of us clean up the mess left behind.

    OK. It was me, not Doc that made the statements about the coal lobbies, and the appeal to authority. So I will answer for it.

    The coal lobby is actively against nuclear power because it is a competitor for base load generation. Up thread you will find a link to Rod Addam’s site were under the topic ‘The Smoking Gun’ he has been collecting evedence of this for some time now, I refer you there.

    The appeal to authority that I made was only in response to one of our regular sob-sisters who was guilty of exactly the same thing; trusting Greenpeace, because it’s Greenpeace. I was illustrating the error of that approach, which was made clear in subsequent entries.

    My background, which can be read in detail by clicking on my name, is that of an industrial chemist and metallurgist, and while I have never worked for the nuclear industry directly, I am qualified to make educated comments on the field. Nuclear energy (fission in particular) is not that mysterious or complicated, nether are the ancillary technologies that support it. Anyone with background in the sciences can understand it.


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  52. 52
    DV82XL Says:

            Poul-Henning Kamp said:

    JCredible sources claim that even if you just drop one slightly subcritical Pu-240 on top of another, for instance in a penthouse apartment, you will, apart from dying pretty instantly, have made for a really really lousy day at the DHS./phk

    Show us those ‘credible sources’ please.


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  53. 53
    Poul-Henning Kamp Says:

    I think the first time I saw it mentioned was in a Los Alamos publication from the late 1990ies, but I have not kept the exact reference.

    If you search for details on the critically accident at the “Siberian Chemical Combine” in December 1978, you can find the description of an accidental stacking of metallic plutonium of the kind we are talking about.

    From that description, any high-school physics student will be able to figure out how to make a mess which would send half the population of a metropolis into panic, once it gets reported on CNN.

    /phk

    PS: The other thing worth noting is that plutonium may not be as dangerous (“The worlds most poisonous substance” and all that) in the body as radium, from which its dangerousness was extrapolated. The Actinides Quarterly Journal had an interesting review of the “U-P-Pu” kohorte who seem to live on just fine, despite having Pu in their bodies from accidents during weapon production.


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  54. 54
    DV82XL Says:

    The technical problems confronting a terrorist organization considering the use of reactor-grade plutonium are not different in kind from those involved in using weapons-grade plutonium, only to a greater degree.

    • Technical Personnel.
    Competence and thorough understanding will be required in a wide range of technical specialties. These include: shock hydrodynamics, critical assemblies, chemistry, metallurgy, machining, electrical circuits, explosives, health physics, and others. At least several people who can work as a team will be needed. These will have to be carefully selected to ensure that all necessary skills are covered.

    • Costs.
    In addition to support for the personnel over a period adequate for planning, preparation and execution, a considerable variety of specialized equipment and instrumentation will be required, all or most of which need be obtained through controlled sources.

    • Hazards.
    Dealing with radiation, criticality, and the handling of, all present potential hazards that will have to be foreseen and provided against.

    • Detection.
    Assuming the operation is contrary to the wishes of the local national authorities the organization must exercise all necessary precautions to avoid detection of their activities. They would no doubt be faced by a massive search operation employing the most sensitive detection equipment available once it should be known that someone had acquired a supply of material suitable for use as a weapon.

    • Acquisition.
    Very early in the planning and equipment procurement phase the organization will need information concerning the physical form and chemical state of the fissile material it will have to work with. This will be necessary before they can decide just what equipment they will need. The actual isotopic content of the material may be undetermined until it is acquired, making preplanning difficult. The actual acquisition would entail dealing with the problems and hazards that would be set by the safeguards and security authorities.

    The point here being that this is a project that is unlikely to be within the grasp of a paranational organization, at the best of times, and given the poor performance of the one device that was tested by the U.S .using this isotope, a very low likelihood of the device assembling properly when fired.

    Ultimately, despite the fears of the West that such an attack may occur, the probability of one is vanishingly small – not when a semi or two filled with fertilizer and heating oil will yield a much greater explosion, more reliably and at a fraction of the cost.


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  55. 55
    Bill Jones Says:

    The world’s problems solved in one blog. Do you have any readers from Oak Ridge, yet?


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  56. 56
    Bubba Ness Says:

    To Ashton and other non-scientists. Here’s the way I explain it in class. Please pay attention.

    First, imagine every radioactive element has some amount of “natural gas” in it. Each different element has different amounts – some have a lot of gas per pound, and some have very little per pound. Radiation, is the by-products of burning that gas, such as carbon dioxide, carbon monoxide, and water.

    Some elements, burn their gas very slowly – like the pilot light on a stove – so it lasts a long time. Some burn it very fast, like the burner on a stove set to high. Some burn it in a way that it produces more of one by-product (such as carbon monoxide) than another.

    Now if you take an element that burns its gas slowly, it will burn for a long time, but it has a small flame will not burn you unless you directly touch it, and it produces very little quantity of by-products per day. An element that burns the gas fast, will heat the room, an will burn you, and produces a large amount of by-products per day. But that fast-burning element will run out of its gas in a much shorter time.

    Long-lived isotopes are generally not dangerous because they are burning like a small pilot flame, and are harmless to a human unless they hold it close to a delicate part of the body for a long time.

    Short-lived isotopes that produce the dangerous by-products are indeed more dangerous, but they are dangerous specifically because they are burning their fuel fast and thus emitting a lot of radiation. But their gas runs out quickly, and they are soon producing less of the dangerous by-product than the long-lives ones that burn slowly like a pilot light.

    Second, there are only a few radioactive isotopes that can be found in spent nuclear fuel, and they are nothing like the ultra-toxic things you hear about such as Polonium-210 used to kill the Russian. Ultra-toxics can come from certain types of nuclear explosions, and can be made in special laboratory environments, but not in your conventional nuclear reactors used for generating electricity, and they do not come from spent nuclear fuel.

    If you don’t follow this, or you think it is just scientific mumbo-jumbo or lies, check out France. Simple facts – France generates almost all of its electricity from nuclear plants. Yet the total of the hazardous waste from all of France’s nuclear electric plants per year doesn’t even fill up a tractor trailer container. Why? Because France reprocesses their spent nuclear fuel. President Jimmy Carter caved in to paranoid bad science when stopping reprocessing in the U.S. Ample subsequent studies have proven that the earlier fear mongering over reprocessing was essentially baseless.

    Please pay more attention to consensus, per-reviewed science than the Greenpeace (whose original founder quit because it was taken over by non-environmentalist socialists who simply use it as an anti-capitalists tool).


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  57. 57
    DV82XL Says:

            Bubba Ness said:

    To Ashton and other non-scientists. Here’s the way I explain it in class. Please pay attention.

    Good explanation. I’ll be pointing to it often, I think.


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  58. 58
    Dashing Leech Says:

    This is a really good article and refreshes my education on the subject from when I was in undergrad about 15 years ago.

    As far as the trolls in here, I have another perspective. I’ve been studying personalities and belief systems for some time and have come to understand that the issue here is about judgment processes. Sure, many people are rational and reasonable (“right brained”) and these people end up in many of the sciences and social sciences. But there is a large portion of the public that makes judgments through perceptive processes (“left brain”) instead of reason. They make judgments based on who’s “story” makes them feel better. That’s why the modern snake-oil industries are so profitable, such as “energy-based healing”. It is arguably why religion is so widespread as well.

    Human beings are attracted by great story-telling. When warm and friendly people tell them great stories, and about their heroic efforts to help the Earth and be in tune with nature, and that there are easy answers that the evil scientists and politicians are trying to hold down, there is a trust formed. The rational right-brain crowd tend to be poor at being warm, inviting, and at story-telling. The scientific method might be objective and rigorously come up with the right answers, but that makes it inherently cold and unfeeling. This attitude just fosters the image in the left-brainers’ minds that we are cold and uncaring.

    Having debated with left-brainers my whole life, it is quite apparent that proving them wrong is irrelevant to them and merely makes their impression of you even worse, thinking that you just like to argue and “just have to be right”. Insulting them just adds to that as well. When a left-brainer is convinced by someone they trust that 2+2 = 5, you can prove them wrong as many times as you want, but that just makes them dislike you even more, trust their source more, and remained convinced that 2+2 = 5 despite all evidence to the contrary.

    This sounds insulting, but left-brain thinking does have evolutionary advantages outside of finding objective truth. Evolution is driven by reproductive success, which is as much driven by social interactions that lead to reproduction as it is survival through improvement of objective knowledge. It’s difficult to measure, but it appears that left-brainers reproduce successfully at equal or greater rates than right-brainers, arguably due to a balance between their increased tendency to reproduce at all with their reduced success from ignoring the best objective information. (For example, children are less likely to survive if their parents use prayer instead of medicine or listen to Jim Carey and Jenny McCarthy about not giving inoculations due to unwarranted fears.)

    So we can’t just dismiss left-brainers. They are a large part of the population, potentially a majority, and as such have some power over policy in a democracy. What we right-brainers need to do is learn how to better communicate with left-brainers. We need warm and friendly scientists who are good at story telling to be the promoters of science and perform the education of the public on these topics. We need more people like Richard Feynman and Carl Sagan. Even Stephen Hawkings is quite decent because of the compelling drama of his life. David Suzuki isn’t too bad either, but I’ve been greatly disappointed that he has associated himself with activist organizations, including Greenpeace that promote anti-intellectualism, over consensus building within the scientific departments and circles that the government actually listens to. He has set himself up for failure and ridicule by doing so even if he has the right information.

    This might be a long aside about personalities, but I think it is as important that scientists understand their audience as much as the audience understands the science. And since the scientists old and young in here seem impressively rational, I hope you can understand our need to change our public face. I don’t know the best way to start a movement in that direction, but even one person at a time is a start.

    I’ll definitely be reading more here. The information density is quite high while not appearing to talk over everyone’s head. Good job.


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  59. 59
    DV82XL Says:

    Regrettably, Dashing Leech, you have made a valid point, and one worth taking into consideration.


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  60. 60
    Eric Says:

    There is at least 1 spent fuel reprocessing plant in the United States that never went into full operation. The facility was built by GE and got contracts from nuclear facilities to accept their spent fuel, anticipating that they would be able to resell the fuel back to the nuclear plants.

    After they got the contracts and during final construction of the facility Carter made reprocessing illegal, yet GE is still responsible for accepting the nuclear waste from the nuclear reactors they contracted with. Now the facility has spent fuel sitting in swimming pools indefinately because they have nothing to do with it.

    I toured the facility years ago, and that’s when I learned about Carter’s decision. This desperately needs to be overturned…why hasn’t it already been done?


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  61. 61
    Ugly American Says:

    There are geothermal plants that have been in operation for over 100 years and sell their power for $0.01 a kWh & there are wind turbines selling power for $0.03 a kWh but the very best the nuclear industry can even promise is $0.07 a kWh if they get subsidized financing & the government pays for all the waste internment for the next 10,000 years. The Yucca dump is now expected to cost taxpayers $90B and isn’t even finished yet.

    Nuclear apologists like to claim reactors cost $1B when in fact Browns Ferry 1 took $2B just to fix and the industry’s own numbers project new reactors would cost $6B if they start now and nothing goes wrong while Moody’s Investors Service estimate the true cost at $7B unless something goes wrong.

    Read the MIT study on geothermal power. We have a 30,000 year supply. Read the nuclear industry study on worldwide U235 reserves. The entire world only has 80 years at the current rate of consumption and people are talking about doubling or tripling the number of reactors. They’d run out of fuel before they were even paid off.

    That’s why private investors won’t build reactors with their own money – only taxpayer money.


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  62. 62
    DV82XL Says:

            Ugly American said:

    There are geothermal plants that have been in operation for over 100 years and sell their power for $0.01 a kWh & there are wind turbines selling power for $0.03 a kWh but the very best the nuclear industry can even promise is $0.07 a kWh

    And of course wind isn’t subsidized, and dry-rock geothermal is cost effective and you have the references to back this up.

    We’ve heard it all before, it never comes with complete numbers.


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  63. 63
    Finrod Says:

            Ugly American said:

    There are geothermal plants that have been in operation for over 100 years and sell their power for $0.01 a kWh & there are wind turbines selling power for $0.03 a kWh but the very best the nuclear industry can even promise is $0.07 a kWh if they get subsidized financing & the government pays for all the waste internment for the next 10,000 years. The Yucca dump is now expected to cost taxpayers $90B and isn’t even finished yet.

    Nuclear apologists like to claim reactors cost $1B when in fact Browns Ferry 1 took $2B just to fix and the industry’s own numbers project new reactors would cost $6B if they start now and nothing goes wrong while Moody’s Investors Service estimate the true cost at $7B unless something goes wrong.

    Read the MIT study on geothermal power. We have a 30,000 year supply. Read the nuclear industry study on worldwide U235 reserves. The entire world only has 80 years at the current rate of consumption and people are talking about doubling or tripling the number of reactors. They’d run out of fuel before they were even paid off.

    That’s why private investors won’t build reactors with their own money – only taxpayer money.

    Utter garbage.

    The assertion that private enterprise is unwilling to risk capital to build nuclear power plants is an outright lie.

    The projected price of all power generating infrastructure has been rising with rising global demand for the materials necessary for any major industrial plant. In comparison with other power sources, nuclear fission still trumps everything else.

    The amount of nuclear fuel (uranium and thorium) present in the Earth’s crust and recoverable is sufficient to last us for as long as the sun remains on the main sequence.

    Even if large-scale geothermal power becomes practical, it will be utterly marginal compared to the capabilities of nuclear fission. No one in their right mind would build a geothermal plant when the mature nuclear alternative becomes available.

    Wind and the rest has been sufficiently well debunked elsewhere to make any statement here redundant.


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  64. 64
    Neurovore Says:

    All political arguments about the reprocessing of spent fuel aside, could reprocessing of nuclear fuel ever actually hope to compete on an economic basis with simply mining more uranium? As far as I understand it, mining fresh uranium ore is still much cheaper than actually reprocessing spent fuel which is part of the reason why there is not much enthusiasm for lifting the idiotic ban on nuclear fuel reprocessing that Carter imposed during his administration.


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  65. 65
    George Carty Says:

    Isn’t that the main argument used by supporters of the LFTR – that is is far more economical to operate because it does its own reprocessing?


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  66. 66
    drbuzz0 Says:

            Neurovore said:

    All political arguments about the reprocessing of spent fuel aside, could reprocessing of nuclear fuel ever actually hope to compete on an economic basis with simply mining more uranium? As far as I understand it, mining fresh uranium ore is still much cheaper than actually reprocessing spent fuel which is part of the reason why there is not much enthusiasm for lifting the idiotic ban on nuclear fuel reprocessing that Carter imposed during his administration.

    It depends on a number of factors, like the method of reprocessing and scale. Areva says that they can do it at a price that is on par with new fuel. However, it makes more sense if you include the savings in disposal and not just the price of new fuel. When you consider the ridiculous amount of money sunk into Yucca Mountain and the whole disposal backend then the reduction in spent fuel improves the economics of the process dramatically.


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  67. 67
    Soylent Says:

            George Carty said:

    Isn’t that the main argument used by supporters of the LFTR – that is is far more economical to operate because it does its own reprocessing?

    It depends on a lot of things.

    It depends on the reprocessing method(purex is awful; it gives you liquid waste and produces pure plutonium, which will be weaponsgrade if LWR fuel that has been in the reactor a short amount of time is used). It depends on your goal(e.g. producing plutonium to seed LFTRs from spent LWR fuel, producing MOX fuel for LWRs, extracting valuable platinum group metals from spent fuel etc…). It depends on what kind of spent fuel you are reprocessing and how long the fuel that you’re reprocessing has been allowed to cool. It depends on the cost of producing uranium from lower grade deposits and sea water. It depends on how low the cost of reprocessing can be made using newer technologies. It depends on how cheap safe storage of fission products can be made after they have been liberated from the uranium oxide ceramic(e.g. through glassification).


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  68. 68
    Paul Eckerson Says:

    The basic problem with our government is that they won’t do anything tha makes voters angry enough to vote them out. So if you make enough noise (just like spoiled children) you will get your way. Everyone with any basic science education knows this problem needs to be addressed and the science community should be left to resolve the problem. All this stored fuel at current reactor sites is a far greater threat as a terriorist target than the danger posed by the Yucca Mountain plan. I too agree that any new reactors built ought to be designed to minimize radioactive byproducts with the best current proven technology and reprossesing current ought to be employed. Look what France is doing!
    In otherwords, the cost of disposal needs to be factored into the cost upfront. This approach in fact ought to imposed on all products. If we put the cost of disposal into products, companies will design products to eliminate waste, disposal and environment impact. No government laws would be needed.


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  69. 69
    Lars Says:

    For the chemists in the audience.
    In most LFTR designs the first step in processing the fuel is to extract U, Np, and Pu and put it back into the reactor. This is done by fluorination. Pu is tougher but ORNL showed it could be done. The process is normally expressed as being able to remove 99%-99.9% of the U and Np and 90%-99% of the Pu.
    But I’m wondering if this is the right way to look at things.
    I’m thinking if we start with a higher Pu concentration then we need to plan on a second pass through the fluorinator to do a good job of removing the Pu. So rather than thinking of it as a percentage remaining it is a residual amount that remains and higher initial concentrations mean multiple passes to remove it. Is this correct? If so, how can I estimate what the residual amount is?

    I’ve done some analysis of the waste flow and it is dominated by the waste that leaks through the processing. I’d like to understand how much we can reduce this.


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  70. 70
    drbuzz0 Says:

    Hi Lars. Yes, the LFTR is a very elegant design. I’m not sure that plutonium should really be that much of a concern, because unless you add plutonium or U-238 from the beginning, perhaps in order to burn it or something, then there should be pretty negligible amounts of plutonium produced. The only way you’d get plutonium would be to have either U-233 absorb a neutron and not fission (which is a small percent) to produce U-234, which would absorbe a neutron to produce U-235, which will also usually fission. If U-235 does not fission upon absorbing a neutron you have U-236. U-236 has a small cross section and will usually just sit there but with enough irradiation a small portion will absorb a neutron and then rapidly decay by beta emission to Np-237.

    That’s quite a chain of low percentage interactions to get all the way to Np and then Pu. I’d therefore have to assume that any amount of transurics would be extremely small.


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  71. 71
    Lars Says:

    The inventory inside the reactor for an LFTR running a Th/U cycle is 350 kg of Pu. When we start up it is closer to 8,000 kg whether we start with u235 (20% LEU) or TRU’s. So, I’d like to reduce as much as possible the Pu that flows to the waste. With lots of power plants world wide the flow still adds up to something noticeable.


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  72. 72
    arcticcc Says:

    You know, fusing these materials into inert form and storage in the desert is a perfect solution. We can easily give up 40 sq miles of Nevada for this storage. What so many of the folks here dont think of is that these are our grandchildrens raw materials. It is wastful and arrogant to think of the oft stated but horribly expensive solutions of drop in the ocean trenchs, bottoms of old mines/ wells, shoot it to the sun.
    Just like the plastics that were burned off as waste in the early days of oil production, or the landfills / aluminum mines of our future.
    We need to be more aware that the future generations will appreciate us leaving our “waste” for them.
    mv


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  73. 73
    George Carty Says:

    I just happened on this thread again, and Dashing Leech’s comments about left-brainers and right-brainers (hmm, has he got them the wrong way round? I thought that left-brainers were the rationalists…) reminded me of the Why We Fight World War II propaganda films.

    These films (plus some other US propaganda films of the same era – Here Is Germany for one example) used two narrators (Walter Huston and Anthony Veiller) with very different styles. Perhaps this was done in order to appeal to both personality types…


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  74. 74
    Shafe Says:

    There’s a lot of talk about “nuclear waste” and what should be done with it. There are different categories of radioactive waste which include everything from very low level material like contaminated lab coats and beakers from radiological tracers all the way up to highly concentrated high-energy radiation sources.

    Do the solvents used in the refining, enrichment, and reprocessing of nuclear fuel represent a major waste stream? Numerous 80′s era movies use the image of hundreds of 55-gal. drums full of liquid “nuclear waste” deteriorating and leaking or being dumped into the sea by malevolent corporate types. What is the actual fate of these solvents? Are they reclaimed and reused? Are they rendered harmless somehow?


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  75. 75
    Fat Man Says:

    This thread is still leaking comments to the e-mail system. Is there any way to close it?


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  76. 76
    drbuzz0 Says:

            Fat Man said:

    This thread is still leaking comments to the e-mail system. Is there any way to close it?

    What do you mean “leaking comments to the e-mail system”

    Do you mean you signed up for email notifications on it?


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