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What is environmental impact for mining, processing nuclear fuel?

  1. Jun 10, 2010 #1
    The month long debacle over the BP oil spill, and earlier collapse of a coal mine killing scores of coal miners, makes me wonder:

    what are the risk to human safety and environmental impact for mining, processing nuclear fuel (i.e uranium, thorium) ? Could acquiring nuclear fuel lead to a catastrophe analogous to BP oil spill or coal miner death? How much land is destroyed in order to acquire uranium or thorium ore? Most of the anti-nuke opposition centers around reactor core meltdowns like Chernobyl and 3 mile island. I supported Sarah Palin's call, Drill baby Drill, as I believed more oil is good. I never dreamed one morning I would wake up, turn on the news, and hear about DeepWater. I also supported John Mccain's call for more new nuclear plants. Is it possible that one day in the news, a uranium mine or thorium mine collapsed killing dozens of miners, or exploded creating a plume of uranium radioactive ash?
     
  2. jcsd
  3. Jun 10, 2010 #2
    Radiation is one of those scary things that you always hear about, but that most people don't understand. I was part way through my 3rd year of university (engineering physics) before I got a basic understanding of the types of radiation and biological effects.

    Ionizing radiation (the stuff usually associated with nuclear and radiation therapy) is most simply described as highly energetic particles. These can be electrons, protons, photons (light), helium, neutrons and many more particles.

    Basically, these particles have so much energy, they can potentially make it into your body and cause breaks in chemical bonds. This includes the bonds which hold DNA together. A very small percentage of the time this can lead to cancers and some other disorders. This is especially true in people that are still growing (or pregnant for example).

    It is important to note, that radiation is common and natural. Humans have evolved with ionizing radiation from space and from the earth causing these same things to occur. This is not a new threat.

    Now back to mining...
    Uranium mining is much like any other mine, except generally with more safeguards because of the fear associated with radioactive materials. Uranium ore is safe enough that it can safely held with gloves. Typically face-masks are also worn to prevent inhaling the radioactive dust. The radiation most associated with uranium is alpha particles (helium) and photons (which are actually produced by the things that uranium decays into). Your skin protects you from alpha particles, so they are mostly only dangerous if you inhale or eat them.

    There are some unique risks associated with uranium mines, namely the potential for water contaminated with radioactive isotopes to contaminate nearby lakes and streams if something goes wrong (eg leaking tailings pond). Keep in mind however, that other types of mines also have issues although they are normally chemical instead of radiological concerns. In this way the fear of spills and leaks is pretty much the same for traditional and uranium mining.

    Uranium mines, like other mines, can collapse. However, they can't catch fire and explode like coal mines, and typically have much better ventilation. Also, uranium is typically found in rock fromations which are stronger than coal deposited so there is reduced risk of collapse (although not zero). Since there can't really be an explosion, there is no risk of a dust cloud to worry about. (Other dust clouds would be pretty small, and would not spread very much radiation). Generally, I would say that worker at a uranium mine would be much safer than coal mines (although I am not a mining engineer).
     
  4. Jun 11, 2010 #3
    As far as I know all of the underground mining (McArthur River and McClean Lake) in Canada is done by robots. Because the two underground mines in Canada have uranium at such high concatenations the ore is practically at fuel grade enrichment out of the ground. This makes it too hot for people to be in the mine under Canadian work place laws. Canada also has one open pit mine (Rabbit Lake)

    The USA mines (all in moth balls right now) use an In-situ leach mining process. If you were to goto the mine site it would look like an oil field. As for the reason that the USA dose not mine for uranium right now is we are buying a bunch of weapons grade uranium from the Russians and down blending it to make fuel. This has been going on since the early 90's and if I remember correctly we are in talks to extend the program

    In Australia there is underground (Olympic Dam) open pit (Ranger) and In-situ leach (Beverley).

    I think that covers the major players in uranium mining worldwide.
     
  5. Jun 11, 2010 #4

    Astronuc

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    I''m not sure from where this information originated, but uranium ore in the ground does not have fuel grade enrichment - unless one is referring to CANDU fuel - which uses natural U in a heavy water moderated core. It might have an 'ore' concentration of 2-3%, but the U-235 concentration is still about 0.71%.

    In addition to U, some other elements such as vanadium may also be extracted from deposits.

    As Hologram0110 indicated, the mining or U ore has much the same risk as mining other minerals - a lot of materials is dumped in order to get the little bit of ore.

    The radiation is an issue for those around the mine, or who live near tailings. There was a case where tailings were sold for contruction material in Colorado.

    Radon is an issue in U mines, but also in coal mines. In fact, coal often has amounts of heavy metals - mercury, thallium, arsenic, . . . . associated with it.

    http://www.ornl.gov/info/ornlreview/rev26-34/text/colmain.html [Broken]

    http://www.wise-uranium.org/mdafin.html

    On the other hand, uranium produces about 3 million times the thermal energy of coal, so 1 gram of U produces slight more energy than 3 Mg or 3000 kg, or 3 MT of coal.
     
    Last edited by a moderator: May 4, 2017
  6. Jun 11, 2010 #5
    This is a key point, and one that seems to escape the understanding of the innumerate.
     
  7. Jun 11, 2010 #6
    The issue in mining is mining, not that you are mining a radioactive substance. I would rather mine Uranium than Coal! The environmental impact and the rest tends to be standard mining damage, not something unique to Uranium. As Astronuc said, Coal mines are horribly dangerous compared to the highly regulated mining of Uranium. Heck, I'd rather mine Uranium than Diamonds too.
     
  8. Jun 13, 2010 #7
    This is the most important fundamental thing that should be the first thing that anybody learns if they have questions about nuclear power.

    For typical coal-combustion power generation, approximately four million tonnes of coal needs to be dug up and burned per gigawatt-year of electrical energy.

    For the relatively inefficient once-through use of low-enriched uranium in existing LWRs with no recycling or reprocessing, you need to mine approximately 170 tonnes of natural uranium to get one gigawatt-year of electrical energy. If the ore is, say, 1% U, then you need to turn over 17,000 tonnes of rock per gigawatt-year, which is absolutely trivial compared to coal.

    When you really use nuclear fuel efficiently, in IFRs or LFTRs or similar, you need one tonne of natural uranium, or depleted uranium, or recycled U/Pu from LWR fuel, or thorium, to get one gigawatt-year of electrical energy.

    To get an idea of how dangerous uranium mining really is, simply look critically at the direct empirical experience from history.

    Over say the last 10 years, how many people have been injured or killed in uranium mining?

    Now, for comparison, over the last 10 years, how many people have been injured or killed mining coal?
    What about oil, or gas?

    There is a very large amount of "depleted" uranium around the world, being stored - about a million tonnes.
    There are also the stockpiles of once-through-used "spent" LWR fuel, which is perfectly good fuel.
    There are also the 3200 tonnes of mined, refined, pure thorium nitrate that the US government buried in Nevada because they decided they didn't want it.

    When we start using nuclear energy truly efficiently, there would actually be little or no need to actually mine uranium ever again. These already-mined resources represent many centuries of energy.
     
  9. Jun 13, 2010 #8

    mgb_phys

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    The McArthur River/Cigar lake ore body is >20% U3O8 (about 10x the typical ore concentration) which makes it very economical but your have to be a little more careful.
    Mainly you need to wear respirators around production faces and you don't want to stockpile too much in one heap!

    It's in Canada so the safety and environmental standards are pretty high - like most mines the main dangers are underground traffic and the flight to get there!
     
  10. Jun 13, 2010 #9
    Silicosis and other respiratory illnesses are often the greatest danger in mining, including mining for Uranium. That doesn't really have much to do with Ur however, just the nature of the beast when you work around a lot of particulates. Uranium in Canada is heavily regulated, but in various parts of Africa for instance, the death rates from the family of COPDs is much higher. Radon exposure is also a cancer risk for less regulated mines, but again, Gold, Diamond, and Coal mining are far FAR riskier, and often less regulated even in the third world.

    Let me add an example, from South Africa: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1758522/
     
  11. Jun 13, 2010 #10
    Are there any breeder type reactors in the US that can process spent fuel, and if so, why is there a need to store nuclear waste for thousands of years?
     
  12. Jun 13, 2010 #11

    mgb_phys

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    No
    1, nuclear is scary dangerous so you couldn't build one in the senator's state (for any value of senator)
    2, the French and Japanese can build a (reasonably) succesful breeder so there is no challenge and America wouldn't build anything if there wasn't a challenge
    3, you don't want to waste Pu when it can be used much more profitably in bombs
    4, what's the problem of storing waste long term - there is all that desolate wasteland between Boston and Seattle anyway
     
  13. Jun 14, 2010 #12
    NIMBY, is the beginning and end of the nuclear issue. People are happy to suck coal byproducts, but god forbid there could be an accident that probably only harms people IN the plant. /end wry tone

    Really, #1 is it.
     
  14. Jun 14, 2010 #13

    That might be true in general for nuclear power, fast reactors are especially politically unpopular. For breeding you work, practically, you eventually have to reprocess fuel to remove the fission products. Some methods used to do this can be used to produce pure plutonium and are therefore considered a proliferation issue.

    From Wikipedia:
    Anyone know the details of the Savannah river site? Will they do reprocessing on site or will they consume stockpiled Pu from the weapons programs?
     
  15. Jun 14, 2010 #14

    Astronuc

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    The goal with that site is to dilute WG Pu into commercial LWR fuel. Unless they've built it to the same standards as Marcoule or La Hague, it will only be used for conversion of WG-Pu for commercial fuel and not reprocessed Pu from LWRs or FBRs.

    FYI - http://www.fissilematerials.org/ipfm/site_down/rr04.pdf
     
  16. Jun 27, 2010 #15

    Morbius

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    The only reason for storing the waste instead of reprocessing it is because the
    Government, at the behest of the anti-nukes; killed off reprocessing back in the '70s.

    Dr. Gregory Greenman
     
  17. Jun 29, 2010 #16
    Is there a valid reason to do this?

    Is it possible to reprocess currently stored nuclear waste?
     
  18. Jul 3, 2010 #17

    Astronuc

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    Valid reason to recycle, or not recycle?

    Spent fuel can be reprocessed as it done in Europe.

    Reprocessing is expensive, but then so is the permanent storage in a repository.
     
  19. Jul 6, 2010 #18
    so the claimed breeder reactor advantage isn't much of a cost savings over 1-through cycle?
     
  20. Jul 6, 2010 #19

    Astronuc

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    Careful. One is mixing breeding of fuel, primarily Pu-239/240, with recycling/reprocessing LWR spent fuel. The two are different, but generally, reprocessing/recycling is more expensive than once through. However, that is contingent upon the actual backend costs of the once through cycle - which have increased over the years.

    Reprocessed fuel requires remote handling which makes fabrication much more expensive, and the QC/QA more difficult.

    On the other hand, for countries without significant resources of uranium ore, reprocessing might be economically attractive.
     
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