Energy. Environment. Economy.

Study finds acid mine drainage reduces radioactivity in fracking wastewater

A rock pulled from the bottom of a creek in Tioga County is covered in orange slime, resulting from iron sulfide in mine water drainage.

Susan Phillips / StateImpact Pennsylvania

A rock pulled from the bottom of a creek in Tioga County is covered in orange slime, resulting from iron sulfide in mine water drainage.

Using polluted water from abandoned coal mines to frack natural gas wells has been suggested by the state and some environmentalists in Pennsylvania. Now, researchers at Duke University have found it could leverage one industry to help clean up the toxic legacy of another – and vice versa.

A peer-reviewed study published last month in the journal Environmental Science and Technology shows that when mixed together, acid mine drainage can act like a treating agent to remove radioactive material from fracking wastewater.

In the lab, samples provided by the natural gas industry were blended together. In about 10 hours, radioactive elements like radium and barium combined with the sulfate in the acid mine drainage to create a solid mineral called strontium barite.

Duke Professor Avner Vengosh, a co-author of the study, explained those solid minerals can be removed and disposed of in landfills and the water leftover can be used to frack new wells or sent to facilities for more treatment.

“So we see it as kind of a win-win situation,” said Vengosh. “You’re not just dumping acid mine drainage into the environment, but actually using this instead of valuable fresh water.”

Vengosh also co-authored a study published last fall that found high levels of radiation and salt in a creek near a drilling wastewater treatment facility in western Pennsylvania. He says mixing it with acid mine drainage could prevent these problems.

“If you are blending it with water from fracking fluid that could be disposed to the environment, you’re preventing this contamination from the creeks,” he said.

Fracking just one well can take more than four million gallons of water. The state has discouraged the use of fresh water sources and instead, wants drillers to use water from miles of lifeless streams that have been polluted by coal mining.

But some gas drillers are hesitant to use acid mine drainage out of fear that they will be liable for cleaning up these streams forever. A bill making its way through the Pennsylvania legislature aims to lower their liability.


  • Iris Marie Bloom

    Yikes, this post is terribly misinformed about the bill (SB411) it mentions. This StateImpact piece concludes “as if” the bill is purely beneficial for the environment, but that’s not the case at all. Responsible environmental groups across the state, in fact, are opposing it and many of us are urgently calling our state Senators TODAY to oppose it. Unfortunately, the bill is actually cleverly written by the fracking industry and their friends in such a way as to relieve fracking corporations from responsibility for leaking toxic fracking waste, or wrongly disposed of fracking waste, even if that toxic waste shows up in a stream or on land where it shouldn’t be — just because said corporation uses Acid Mine Drainage water in their fracking! No corporation should be let off the hook for pollution, so everyone should oppose SB411 because it does just that. The timing of this post is odd, as if it is lobbying for a bill that just happens to be voted on today. Please look into the complexities of controversial legislation, StateImpact, and don’t oversimplify so dangerously. SB411 must be opposed.

  • Mountain Watershed Association

    Iris writes very well on the follies of this bill. At
    the Mountain Watershed Association we’ve worked for years to clean up and
    contain acid mine drainage (AMD) in the Indian Creek Valley (ICV). It is
    unwise to start moving AMD to other locations, this will inevitably lead to the
    contamination of additional watersheds. We work hard to remove AMD from
    our rivers and streams in ICV and the thought of this material being
    transported and used to encourage another deadly industry is appalling. This sort of interbasin transfer will still end up moving
    critical amounts of water from one hydrologic system putting the ecosystem of
    that system in danger. If this bill goes
    through PA’s waters will never be clean and her watersheds never restored.

  • AlSever

    Not cost effective! Another pie in the sky scheme that will only work if subsidized with Gov’t money. Besides the vast majority of frac water is NOT radioactive!
    And just what Barium concentrations are they talking about? In two years of dealing with Frac wastewater, we have seen incoming wastewater vary in concentrations from 0.0 mg/l to 8,000 mg/l. Every well is different just like every Coal mine discharge is different.

    • Mimi

      Hi Al,
      It’s good to read something which doesn’t promote panic over every conceivable environmental issue. Don’t confuse these people with facts. Everything done to use natural resources is “bad”, “polluting” etc., etc. Do these same people know how many eagles have been and are being killed by wind turbines? Not to mention other birds. Oh well, that’s the trouble with ‘liberal’ thinking, if all you have is a hammer, everything looks like a nail! Don’t expect independent thinking, or in depth research on the issue. Just keep on telling people they will have fire coming out of their faucets, and they’ll be radioactive as well!
      Bugger! as the English say.

  • NorthernTier

    In view of their history, it will be interesting to see how the PA DEP reacts to this new Duke/Vengosh study … if at all.
    “Duke Researchers Push Back on DEP’s Critique”

  • JimBarth

    I’m not up to speed on the bill itself, but, the immediate question that arises in my mind is, exactly what is improved by removing whatever radioactive elements that may be in the flow back waste, and then creating a solid radioactive substance that needs to be dumped in a surface landfill?

  • Tom DiStefano

    Wouldn’t using acid water to frack dissolve and bring to the surface more radioactive metals, that would then have to be removed and disposed of at the surface?

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