Opponents of natural gas drilling have consistently spread fear by alleging that hydraulic fracturing contaminates groundwater and releases methane, saline and arsenic into water wells. The Internet is awash in videos showing people lighting their tap water on fire and assigning the blame to drilling. (Remember the “documentary” Gasland?)
However, a just-released study by the Duke University Nicholas School of the Environment demonstrates that these kinds of claims by the anti-fracking crowd are false.
Duke geochemistry and water quality professor Avner Vengosh and his team examined 112 drinking wells over a three year period in the heavily-drilled area of northwestern West Virginia. The researchers were able to sample 20 water wells before drilling began to establish a baseline for comparison.
Vengosh reached this unambiguous conclusion: “We did not find any evidence of groundwater contamination from shale gas development.”
Yes, the researchers did find varying levels of methane and arsenic, but through the use of special geochemical “tracers,” they determined the substances were naturally occurring or a result of old wells or coal mines from years ago.
The Appalachian Basic rock formations tend to have high concentrations of methane, saline and arsenic. Their presence in aquifers “was found to be a widespread phenomenon and likely a result of natural migration of deep brine and natural gas-rich fluids combined with shallow water rock interactions.”
In some cases, arsenic concentrations exceeding national drinking water standards were found in water wells before shale gas development.
However, the peer-reviewed study does not let the gas drilling industry off the hook. The researchers concluded that accidental spills of fracking wastewater at drilling and disposal sites may pose a threat to surface water. “Management of wastewater is the weakest part of shale gas development,” Vengosh said on Talkline this week. “Once wastewater comes out, managing it correctly is really a major challenge.”
That’s a critical point, and an area where regulators working with the industry need to increase their vigilance.
Last year, the EPA released a preliminary study saying it found “no evidence that fracking systemically contaminates” water supplies. The Agency took so much heat from environmentalists that it struck that that conclusion from its final report.
The Duke researchers, who have been the leaders in fracking studies, do not appear as susceptible to political whims. It’s worth noting that this most recent study was funded by grants from the Natural Resources Defense Council and the National Science Foundation.
This study serves as solid science in the fracking debate that will come in handy the next time someone rolls out a video of burning tap water.