Scientific Residue


Taking a break from the usual content, I thought the toxic spill of some 2.8 million cubic feet of coal fly ash warrants a reminder that fly ash is not only toxic, but it’s been shown to be even more radioactive than living near a nuclear plant.

At issue is coal’s content of uranium and thorium, both radioactive elements. They occur in such trace amounts in natural, or "whole," coal that they aren’t a problem. But when coal is burned into fly ash, uranium and thorium are concentrated at up to 10 times their original levels.

You might not get to hear this particular information on media outlets sponsored by "Clean Coal." The TVA, for its part, isn’t even admitting the ash is toxic.

 

  1. #1 by Wulf on December 24, 2008 - 8:09 pm

    Avi, the concerns are chemical, not nuclear. Arsenic and mercury are in the coal ash and can get into water sources, but the Scientific American article you link is very misleading about radioactivity. Coal ash has only trace radioactivity… way less than nuclear waste. Please see my fisking of the nuclear concerns.

    Still, this is amazing.

  2. #2 by avi on December 24, 2008 - 8:46 pm

    The McBride study, as I understand it, compares normal radiation exposure for people leaving near coal and nuclear facilities. Coal came out higher, though both were much less than the typical background dose we all may get from various sources. I think the article is very clear on those points, so I wouldn’t call it misleading.

    Now, this fly ash spill wouldn’t even come close to the radiation exposure from a Chernobyl-style nuclear accident. But given the odds of a spill like this vs. a nuclear accident, coal again comes out worse on the radioactivity comparison.

    Bottom line, the heavy metals, both radioactive and merely toxic, are probably going to stay in the groundwater for a long, long time. And any exposure to the sludge should be treated extremely cautiously.

  3. #3 by Wulf on December 25, 2008 - 10:32 am

    The title of the article is “Coal Ash Is More Radioactive than Nuclear Waste”, which is completely false.

    This statement from the article is also false:
    “the waste produced by coal plants is actually more radioactive than that generated by their nuclear counterparts. In fact, fly ash—a by-product from burning coal for power—contains up to 100 times more radiation than nuclear waste.”

    You don’t think that’s misleading? It’s out-and-out wrong.

    I agree with the rest of your comment, but it really chafes me to see the number of times that horribly written SciAm article is being linked on this story. The danger here is chemical, not nuclear. I hope TVA is held to account.

  4. #4 by avi on December 25, 2008 - 12:10 pm

    I agree that the term “nuclear waste” invokes images of tanks of spent fuel for many readers, which I’d also agree is much more radioactive.

    But “nuclear waste” also reasonably includes other byproducts, like cooling water, steam, and other contamination around nuclear plants. So while I think they could have been clearer, I don’t think the intent was to mislead.

(will not be published)