Article courtesy of Sara Jerome | November 7, 2014 | Water Online | Shared as educational material
As new technologies promise to treat fracking wastewater to a point where it can be reused, there’s a new question: Is it clean enough to drink?
Probably not, says researchers. Returning fracking wastewater to the environment “is just as risky as dumping any municipal treated wastewater back into rivers. As runoff, it is safe but it shouldn’t be done in volume. In the case of fracking wastewater, existing facilities are not equipped to thoroughly deal with halides so until they are ready, it’s simply better to use fracking wastewater for fracking,” Science 2.0 reported.
The study, published in Environmental Science & Technology, focused on the contents of fracking wastewater. Part of the problem is what happens in the treatment process.
“Most sites recycle the water but one approach has [been] to treat it in municipal or commercial treatment plants and then release it into rivers and other surface waters. The problem is these plants don’t do a good job at removing halides. While there is no evidence yet, there is concern that halide-contaminated surface water subsequently treated for drinking purposes with conventional methods, such as chlorination or ozonation, could lead to the formation of toxic byproducts,” Science 2.0 reported.
Even a little bit of frac water appears to pose a threat in the environment.
“The study showed that even a small fraction, as low as 0.01 percent up to 0.1 percent of hydraulic fracturing fluids in disinfected river water that is used for drinking could result in the formation of disinfection byproducts in drinking water utilities located downstream from disposal or spill sites of hydraulic fracturing fluids,” according to the website of Avner Vengosh, a Duke University professor who helped lead the study.
The study contained suggestions for how fracking wastewater should be approached.
“The results suggest that total elimination of [fracking wastewater] discharge and/or installation of halide-specific removal techniques in centralized brine treatment facilities may be a better strategy to mitigate impacts on downstream drinking water treatment plants than altering disinfection strategies. The potential formation of multiple [disinfection byproducts] in drinking water utilities in areas of shale gas development requires comprehensive monitoring plans beyond the common regulated [disinfection byproducts],” the study said.