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  1. ” Sure, I realize that uranium and thorium require mining…”
    Not necessarily, in fact, thorium breeders and fast reactors don’ t need any new minning, we can produce thousands years of usefull energy for the whole planet ONLY using rare earths mining byproducts (thorium) and nuclear wastes and depleted uranium we have ALREADY produced (with technologies like the Integral Fast Reactor demonstrated in the recent past)
    But I have two question about coal and coal mining : 1) what’s the typical % of carbon in the coal (I guess something in the 80-90% range) and 2) there is always a huge debate about uranium ore grade, but what about *coal* ore grades, in the US or elsewhere, I’ ve never read any data about …

    1. Alex – if you want to use thorium we will need to do a lot of mining; there is not a large inventory of material that has already been mined. There is a about a million tons of POTENTIALLY useful uranium, but there is no existing inventory of facilities that can use it in its present form as fuel. We kind of know how to use some of it based on rather small scale test and prototype programs, but large scale commercialization is NOT in the near future.
      We will be mining uranium for a long time to come, but so what? Mining does not mean large scale environmental damage.

      1. I think there is enough thorium (< 10 thousands tonns/year) as byproducts of RE mining to power the whole planet with thorium breeders, indeed
        But anyway you’re absolutely right, mining doesn’t mean large environmental damages, expecially in a breeding cycle which need only one tonn of uranium or thorium (and even much less) per GWyear vs about 200 tonns per GWyear with current reactors
        Any idea about coal ore grades ?

    2. “Not necessarily, in fact, thorium breeders and fast reactors don’ t need any new minning, we can produce thousands years of usefull energy for the whole planet ONLY using rare earths mining byproducts (thorium) and nuclear wastes and depleted uranium we have ALREADY produced (with technologies like the Integral Fast Reactor demonstrated in the recent past)”
      I don’t think there’s nearly enough fissile inventory to do that.
      Spent nuclear fuel contains ~1% plutonium. The 50 000 tonnes of spent LWR fuel in the US contains ~500 tonnes of reactor grade plutonium.
      The S-PRISM reactor is a sodium cooled fast reactor with both axial and radial blankets. It has a specific fissile inventory of ~12 tonnes per GW of capacity and I don’t believe there is much prospect to drastically reduce it with this type of design. Fast reactors inherently need a big fissile inventory because the fission cross-section is quite small for the main isotopes Pu-239, U-235 or U-233. The redeeming feature of fast reactors is that the capture cross-section is even smaller and essentially all the TRU isotopes look like fuel, even neptunium, higher isotopes of plutonium or americium.
      500 tonnes of reactor grade plutonium allows you to make 40 GW of S-PRISM reactors that will happily munch depleted uranium until the cows come home.
      I’ve seen estimates of a breeding ratio of 1.25 if configured for high breeding. It is possible to give a crude estimate of doubling time. What the breeding ratio means is that for each fissile atom fissioned, 1.25 fissile atoms are created on average. If you assume that only fissile atoms are fissioned(this is not true, some fissionable U-238 will also fission from fast neutrons but its contribution is small) you can calculate how fast fissile material is being created in the reactor.
      I get ~36 years doubling time for a single S-PRISM to produce enough surplus material to start up another S-PRISM. If you instead pool the surplus material from a fleet of reactors and use it to start new reactors as soon as possible instead of having it sit idle I get a doubling time ~26 years.
      Assuming you need as as much fissile inventory if starting from fresh U-235 means you need to mine ~2000 metric tonnes of natural uranium to start up an S-PRISM reactor.
      The only realistic approach to scale up S-PRISM/IFR style reactors fast involves a large expansion of mining.
      The fissile inventory of an LFTR according to Charles Barton and the energy from thorium folks is ~1000 kg U-233 per GW for a self-sufficient breeder(no surplus material) of radial+axial blanket design. A sphere-in-sphere design might be as low as 500 kg ~U-233 per GW.
      Given the thermal spectrum of the LFTR it will not be very well behaved on plutonium. In a thermal neutrons spectrum the plutonium will fission 2/3’rds of the time, the rest of the time it will be transmuted to Pu-240. Higher isotopes of plutonium and americium will build up gradually until it is no longer usuable as fuel in a thermal spectrum. I believe you will have to put a whole lot of plutonium through that reactor until you get enough U-233 to start a “clean” LFTR.
      If you want to start lots of LFTRs really fast you need to mine fresh uranium. Assuming specific fissile inventory is the same for U-235 as for the U-233 it will eventually be operating on you need ~170 tonnes of natural uranium for each GW of LFTR you intend to build.
      I believe the best approach for rapidly scaling up nuclear energy is as follows:
      Continue building LWRs until LFTRs are ready for commercial adoption, from that point essentially all construction of LWRs should cease. Reprocess all spent LWR fuel, isolating fission products into the most appropriate use(vitrified waste, silver and platinoid recovery, industrial or space use of desirable radioactive isotopes etc.) lock up all TRU “waste” within Indian style fast reactors and use all surplus U-233 to start up more LFTRs.
      At some point passed the extinction of LWRs you will have enough U-233 inventory to meet all your needs from thorium and you can start winding the fast reactor fleet down.

      1. ” “Not necessarily, in fact, thorium breeders and fast reactors don’ t need any new minning, we can produce thousands years of usefull energy for the whole planet ONLY using rare earths mining byproducts (thorium) and nuclear wastes and depleted uranium we have ALREADY produced (with technologies like the Integral Fast Reactor demonstrated in the recent past)”
        I don’t think there’s nearly enough fissile inventory to do that….” ”
        Yes, fair enough, given the fact that the world has produced @ 350 kg of LWR/Candu transuranics per GWyear * 2500 TWh/year of nuclear electricity * ~ 30 full years of nuclear production = ~ 3000 tonns of TRUs. That’ s enough to start 3000 GWe of thorium MSR breeders @ one tonn of TRUs per GWe installed as fissile start up (assuming as a rough simplification that TRUs are as good as uranium 233), thus to power the current whole planet energy needs but not to power a near future 10 billions people planet with a western per capita energy need, including the electrification of heating/conditioning and transportation – I think something in the range of 80 thousands TWh/year, that means a base load of nuclear power installed of 10 TWe or about 12 TWe of thorium MSR breeders if operated in the load following mode (~ 6500 full power hours per year)

  2. I gave a course, “All Around the Coal Boiler”, this winter, including a tour of a coal-fired plant. I HIGHLY prefer nuclear, but like you, Rod, if it was coal or no electricity, I would probably choose coal. Also, people simply don’t know we make half our electricity from coal. When I said we were touring a coal plant, the answer from most of my friends was ” you mean there’s a coal plant around here?” (Several, my friends, several. The Massachusetts border is not that far away, Massachusetts has several plants. We toured the one in New Hampshire. We’re not heavily coal-fired up here, but nobody gets away from it completely.)
    A map of coal-fired plants
    A couple of other points.
    1) When I gave the Coal Boiler course, two of my friends were angry at me for saying anything semi-nice about coal. One is my age, grew up in Scotland, lost two uncles in the coal mines in Wales. She emailed me that she hated coal, had been happy to find out I was also pro-nuclear, and what was I doing saying good things about coal? I didn’t have much of an answer.
    My second friend is younger, and lost her father to black lung in his fifties. She said all the men in her family, all those her father’s age or older (including his brothers) had died in their fifties from black lung. I don’t have much of an answer to that one, either.
    2) The slavery in Scotland is not well known, but there is a good novel by Ken Follett which includes escaping from slavery in Scotland and coming to America. A Place Called Freedom
    A quote from the Publisher’s Weekly Review, from the Amazon site above:
    The key to Follett’s absorbing new historical novel (after A Dangerous Fortune) lies in words that “made a slave of every Scottish miner’s son” in the 1700s: “I pledge this child to work in [the laird’s] mines, boy and man, for as long as he is able, or until he die.”
    Well, that pretty much says it all, or at least, all I have to say.

  3. @Rod — Not being a miner, is it correct to say that uranium or thorium mining would be open-pit only while coal is both open-pit and underground? From an energy density standpoint, since the metals are hundreds of times more dense it would seem reasonable to assert that the mining land-use footprint would therefore also be significantly smaller, too?
    As has been suggested here at other times, would it not be more prudent to use the coal in a coal-to-liquid fuel strategy? However, that would still require the mining of coal, so you don’t avoid that activity in toto.
    The reference to the “killing fields” in the trailer, I think, diminishes the atrocity in Cambodia following the fall of South Vietnam. Just heard about this new book: An American Amnesia: How the US Congress Forced the Surrenders of South Vietnam and Cambodia by Bruce Herschensohn.

    1. is it correct to say that uranium or thorium mining would be open-pit only while coal is both open-pit and underground?
      I don’t know what would be best for thorium, but there are many uranium mines in the world which use in situ leach mining. You drill a bore hole or several, pump the leachate down, let it do it’s job, then extract the liquid and process it with very little surface disruption.

      1. And further to that, in-situ leaching works well for uranium precisely because the intended use is for nuclear energy, so chemical modification of the target mineral doesn’t impinge on that resource.

    2. DocF,
      Uranium mining is done underground, open pit and in situ. It depends on the nature of the deposit.
      In situ requires a very specific set of geological requirements to avoid spreading the leachate around.
      A wide spread and relatively low grade ore is normally done open pit. I think most of the mining in Australia and Namibia is open pit.
      Deep and rich vein like deposits are normally done underground. I think a majority of Canadian mines are of this type.

  4. @Rod — Sorry for double-posting, but is the purpose of the second video meant to evoke fear or loathing of these big machinery, the operators of them or the companies that employ them or the industry as a whole? Am trying to gauge my reaction to it and not read anything into the video. Thanks.

    1. Doc – good question. There is no intention of evoking anything other than a recognition of the scale of the machinery involved and the quantity of material being moved.
      I loved playing with Tonka trucks as a youngster and still get impressed when I watch earth being moved around. I just wonder about the annual movement of 1.2 billion tons of it from mines to power plants in the US – 6 billion tons worldwide.

    2. The size of equipment is exemplified by this news item. During February when the ground was frozen a large crane to used in a North Dakota lignite mine was moved. In order to cross a highway, the frozen road bed required additional protection. The highway was closed to traffic while fill was placed over the highway to a depth of 16 feet to prevent breakup of the concrete by the extreme weight of the giant shovel.

      1. John – I recall seeing that type of event back in 1972 on a summer vacation with my folks through ND and MT. To me, the fact that they figured out how much overlay was needed to preserve the roadway was as impressive as the movement of the big shovel.
        To Rod’s point, whether the large mining equipment is used for moving uranium or thorium or coal, it is the efficiency of mechanical tools as opposed to human muscle that is awe-inspiring, to me. The factory line worker assembling the tool doesn’t know what end use that tool will be used for. The manual-laborer who drops his shovel to pick up a hydraulic steerer and scoop is probably glad for the improvement in his working environment.
        My sandbox had plenty of Tonka toys, too! LOL.

  5. Jeff Goodell published his latest anti coal piece “Coal’s Toxic Secret”, in Rolling Stone. Goodell is rabidly anti-coal, and has been for a long time. This article discusses heavy metals in coal ash and the prospects for EPA regulation.
    But, naturally, the article does not mention the uranium and thorium that the ash contains. If too many people start to understand that using coal causes the general population to be exposed to orders of magnitude more radiation than if nuclear power was used instead it would be harder to stop all nuclear power generation.
    I note that Rod’s post does not contain any reference to the radiation hazard of using coal.
    Perhaps pro nukes should consider making more out of the radiation hazard of fossil fuel use, because of the fact that it is so much larger than the radiation hazard of nuclear use, even though the levels involved are so low they might even be found to be beneficial one day. Its a way to bring home the insanity of the critique anti nukes make to the larger environment movement that is sympathetic to them. The same people who ignore radiation in coal ash are buying into arguments that tritium leaks at Vermont Yankee are a serious concern.

    1. Perhaps pro nukes should consider making more out of the radiation hazard of fossil fuel use, because of the fact that it is so much larger than the radiation hazard of nuclear use, even though the levels involved are so low they might even be found to be beneficial one day.
      I don’t agree. I reckon we have more to gain by pushing radiation hormesis as hard as possible, and attacking coal on other grounds. The comparison can still be made in a “What are we so worried about?” kind of way, but over-emphasising radiation danger will backfire.

      1. Its hard for me as a non-expert to make a case other than the one supported by the National Academies, i.e. BEIR VII. This committee noted the existence of the theory that low doses are beneficial but stated “the preponderance of information indicates that there will be some risk, even at low doses, although the risk is small”.
        All I can do with that is move to comparison data, such as living in Denver vrs just about anywhere else, eating a banana, or in the case of an argument about which baseload power source is best, to point to the relative radiation hazard of each.
        I think it is unwise to contradict high level panels such as the NAS BEIR VII.
        There is another what the committee called “competing” theory, i.e. “that low doses of radiation are more harmful than a linear,no-threshold model of effects would suggest” The BEIR VII committee found that the evidence “does not support this hypothesis”.
        But if you say you think the preponderance of evidence supports the theory that low doses are beneficial, you by implication reject BEIR VII and open the door to anti nukes who love dragging out the clowns who want to crucify nuclear over picocuries of nothing as they blithely use coal fired electricity, eat bananas and fly to the meetings.

        1. “I think it is unwise to contradict high level panels such as the NAS BEIR VII.”
          Nonsense! Science is not done by committee.
          There are other groups of highly qualified experts who have looked into this and come away with very different conclusions. Fortunately, these groups were not as cowardly as the NAS committee and avoided resorting to weaselly statements that pretty much say nothing, but only have the effect of supporting the status quo. BEIR VII did not reject a hormesis hypothesis, by the way, it simply claimed that there was not sufficient evidence to support it. Some people have questioned just how hard the committee looked for such evidence.
          The American Nuclear Society (ANS) disagrees with BEIR VII’s conclusion that the LNT model is the “most reasonable.” Instead, it concludes that “there is insufficient scientific evidence to support the use of the Linear No Threshold Hypothesis (LNTH) in the projection of the health effects of low-level radiation.” (PDF)
          The French Academy of Sciences and National Academy of Medicine agree with the ANS that the hypothesis of a linear no-threshold relationship “is not a model validated by scientific data,” and they think that it is “a probably marked over-estimation of the risk of doses lower than a few dozen mSv.” (PDF)
          They go further to point out that many animal studies include observations that are consistent with the concept of hormesis and that our current understanding of molecular biology and cell defense mechanisms “strongly suggest that a threshold or a practical threshold does exist and even, for some cancer sites, as in animals, so does a hormesis effect.”

          1. Thanks for the references. I need to become more familiar with this debate. As I understand it there is substantial disagreement and there are reputable people calling for more data, data that would be obtainable only if a new lab is built. I want to become informed enough to understand why it might be wise to dispute the NAS.
            I don’t think it is “nonsense” to point to the NAS as an authority. Committees set up by prestigious organizations such as the NAS are useful to help the general public understand complex debates where interest groups put forward their arguments backed by PhDs, when for each PhD there seems to be an equal and opposite PhD. Committees are not expected to “do” science, they are expected to assess how sound certain scientific cases are. If an NAS committee says it found that “the preponderance of information” indicates something, it seems to me that those who dismiss this as “nonsense” will end up impairing their own reputation. This particular NAS committee that did the BEIR VII was composed of members from the US, France, the U.K., Germany, Canada, and The Netherlands.

            1. The problem with committees is that they attract politics and special interests like manure attracts flies. In this case, a sizable industry exists worldwide to provide radiological protection. In other words, there are billions of dollars that are regularly spent simply because of the LNT hypothesis and ALARA.
              Are you really naive enough to think that the NAS works in a political vacuum?! No, there are considerable pressures to swing a committee assessment a certain way, and sticking with the status quo is the path of least resistance.
              Committees love the path of least resistance.

    2. If you look at coal from a health physics perspective, then you really start to get scared.
      Coal plants burn pulverized coal. What is pulverized coal? Very, very finely ground coal. Coal dust. Now, in a coal power plant, that very small particle size coal dust gets finely turbulated with oxygen and blown into the combustion chamber where it gets burnt. In the combustion chamber, the process of oxidation removes the carbon from the coal. The only thing left over are the gasses produced by combustion, and the solid materials that aren’t burnt. All of these very fine particles – relieved of their carbon – float up the chimney.
      Among those materials in the coal power plant’s outgassed particulate matter stream are uranium, perhaps a trace of plutonium, thorium, and also other materials like…polonium. Thus, some of this stuff in coal gives off alpha radiation. Some of those particles of coal combustion also are in the “less than 2.5 micron” sizes that can get into people’s lungs – and undoubtedly land in peoples’ lungs.
      Now if we have alpha emitters landing in peoples’ lungs…

    3. Jeff Goodell is good on coal but his effort is marred by a complete ignorance of anything about nuclear. In the entire 250 pages of “Big Coal,” he makes only one mention of nuclear, in the following half-sentence:
      [W]hatever coal

  6. The US has more thorium nuclear fuel than you might be aware of. The United States has at least enough thorium to generate all of the electricity the country uses for 8 years (but unfortunately all this thorium (3200 tons) is currently buried in the ground as “waste”). During the first two decades of the nuclear age the AEC accumulated thorium fuel and stockpiled it for use in Thorium reactors. After mostly successful experiences with thorium in the Shippingport Atomic Power Station and the Fort Saint Vrain Generating Station (HRGR) the nuclear industry and DOE backed away from this technology and concentrated on Plutonium Cycle technology. Thorium nitrate was stockpiled for decades and finally buried and “disposed of” in 2005 at the Nevada Test Site.
    Kirk Sorensen prepared a wonderful Blog post on this subject some while ago:
    “How to Throw Away Eight Years Worth of Electricity
    Published by Kirk Sorensen on July 7th, 2006
    Of great concern to Thorium proponents is the disposition of America’s Uranium-233 which is the fissile part of the Thorium Cycle. Only something like 1500 kilograms of this material have ever existed on the planet and about 1000 kilograms of this is currently stored at Oak Ridge National Laboratory. This rare material is scheduled to be destroyed”” by mixing down with U-238 in 2012. LFTR reactor enthusiasts would like to use the remaining U-233 as a start-up charge for a demonstration pure Thorium fuel cycle reactor that would be able to clearly prove to the world the full potential of Thorium technology in the Fluoride Reactor.”

    1. Robert – I will have to go and read the article that you linked, but can you give a rough description of the number of plants required to produce all of the electricity that the US uses and the number of tons of thorium and U-233 that each of those plants would require to start up and operate for at least the 8 years claimed?
      My point is that I am pretty sure that the infrastructure would require far more than just the quantity of thorium that you mentioned. I recognize that an LFTR has some wonderful potential attributes, including the fact that they should not consume much thorium each year, but they do require a much larger inventory of thorium and uranium in order to start up and operate. You cannot just point to the thorium that would be consumed each year and claim an 8 year supply if you do not also have enough to provide the required inventory.
      Bottom line – though not a show stopper at all, it is not accurate to claim that you can eliminate all mining by shifting to a thorium based economy. Since I happen to like some miners and think that they do a good job of extracting resources without too much environmental harm, I am not even sure why eliminating mining is a useful goal.

      1. Rod – My current duties as a day nurse permit me a only a short answer to your fine questions. I believe that little or no direct mining of Thorium would be required to provide all of the Thorium fuel needed to completely supply all of the electricity used in the United States. The basic reason is that more than sufficient amounts of thorium will be generated as a secondary consequence of mining for rare earths needed for renewable energy systems (Wind generator magnets and parts) and electric vehicles. America’s richest Rare Earth resources are co-located in the same areas as high commercially exploitable Thorium deposits. The tailing piles of the Rare Earth mines needed to supply America’s need for Neodymium and other rare earths will completely provide for all of the Thorium fuel needed to satisfy the nation

  7. An interesting article about coal fly ash radioactivity
    And a graphic from that article The idea in the article is that fly ash is not worse than other materials. However, the photo of a glassy fly-ash particle with uranium in the glass seems more dangerous to me than other materials. Most fly ash nowadays is quite small (<2.5 microns–they catch the bigger stuff) and therefore capable of entering lungs. I am not trying to be chicken-little about this, but the fly ash radiation photo surprised me and I would be happy to hear other people interpret it.

    1. I think that some interesting and relatively cheap research could be done as to the potential for internal contamination by coal particulate matter – a fine thesis project for an environmental engineering or public health student using their local coal power plant (CPP) as the source of particulate emissions.
      One could acquire an alpha detector, and prepare several sample collection trays of gooey to the touch, maybe cohesive silica gel (kind of like jello, but firmer – yet sticky). The trays would be scanned with the alpha detector so as to establish their lack of contamination, and then left outside at pre-scouted locations, some downwind from the CPP, some perhaps 20 or so miles away (and away from any other coal power plants) as a control. They would need to be covered from precipitation, but exposed to the air. After this time period, they could be retrieved and scanned by the alpha detector again. If the alpha detector produces high readings, microscopic examination of the contents of the silica gel could be done to see what kind of particles landed there.
      I wonder what the results would be?

  8. I don’t believe we will leaving all of that coal underground, especially when it looks like in a few years if not sooner this planet will be experiencing tight oil supplies and sky rocketing prices for a barrel of crude. What I do think what will happen for coal is that we will be seeing a transformation on how we get that stuff. Such technologies as underground coal gasification or the injection of microbes in coal seams that produce methane will become much more common. I don’t know what the environmental consequences of such actions will be and I am sure they are not as clean as the World Coal Institute and Luca Technologies make them out to be but I believe that is the direction we are headed. These methods are probably not nearly as bad as mountain top removal, huge open pit mines and workers risking their lives in mine shafts are but hopefully the dark side of these techniques will be understand before we see their wholesale implementation.

  9. Getting back to the the “headline” of the original posting, the United States needs to move from being the Saudi Arabia of coal to being the Saudi Arabia of nuclear. By this, I don’t mean becoming the Saudi Arabia of uranium and thorium, but rather the Saudi Arabia of reactor technology.
    In thinking about nuclear, we have to re-think the old (but common) paradigm of energy. In the case of fossil fuels such as coal, the amount of material used for fuel is much larger than the amount of material used for a power plant to transform the fuel into useful energy. Thus to be the big player in the market, one needs to be in the fuel business (though the power plant business is not bad either). In the case of nuclear, especially with the LFTR and Gen IV uranium reactors, the roles of power plant and fuel are reversed. One of the beauties of nuclear is that with advanced reactors, just about any country could be self-sufficient for fuel. So having reactors to sell to make useful that readily-available fuel is where we need to go.
    Side question: With all the hand-wringing about the tritium leak from the Vermont Yankee plant, I wonder how long it takes to release an equivalent amount of “radioactive dose” from a coal-burning plant of the same generating capacity?

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