Duke U. researcher: wastewater from fracking is mostly natural brines

Again, research confirms that fracking is an intrinsically safe process.

Avner Vengosh, professor of geochemistry and water quality at Duke’s Nicholas School of the Environment, has released a new study of the hydraulic fracturing (fracking) process.

Aside: Remember when The News & Observer was so confident that Vengosh and fellow researcher Robert Jackson were going to find fracking to cause drinking-water problems that they just asserted it did and then criticized Republicans for not doing their due diligence?

Quoting from the press release:

“Much of the public fear about fracking has centered on the chemical-laden fracking fluids — which are injected into wells at the start of production — and the potential harm they could cause if they spill or are disposed of improperly into the environment,” said Avner Vengosh, professor of geochemistry and water quality at Duke’s Nicholas School of the Environment.

“Our new analysis, however, shows that these fluids only account for between 4 and 8 percent of wastewater being generated over the productive lifetime of fracked wells in the major U.S. unconventional oil and gas basins,” Vengosh said. “Most of the fracking fluids injected into these wells do not return to the surface; they are retained in the shale deep underground.

“This means that the probability of having environmental impacts from the man-made chemicals in fracking fluids is low, unless a direct spill of the chemicals occurs before the actual fracking,” he said.

More than 92 percent of the flowback and produced water — or wastewater — coming from the wells is derived from naturally occurring brines that are extracted along with the gas and oil.

These brines carry their own risks, Vengosh stressed. They contain varying levels of salts, heavy metals and naturally occurring radioactive elements, and their sheer volume makes disposing of them a challenge.

“But with proper treatment, they potentially could have beneficial reuses,” he said, “especially out West, where our study shows most brines being produced by fracked wells are much less saline than those in the East. These Western brines, which are similar in salinity to sea water, could possibly be treated and re-used for agricultural irrigation or other useful purposes, especially in areas where freshwater is scarce and drought is persistent.”

The Duke team published its findings Oct. 14 in the peer-reviewed journal Science of the Total Environment.

As it is, over 99 percent of the fluid injected in a hydraulic fracturing operation is water and sand.

For those interested in what is injected deep in the ground in fracking fluid, see the chart at the end of this report. It details the over three dozen most commonly used chemicals in the fracking process according to: its use in the wells, if it’s commonly known, if it’s found in food, if it’s found in common household products, and examples of those products.

Jon Sanders / Research Editor and Senior Fellow, Regulatory Studies

Jon Sanders studies regulatory policy, a veritable kudzu of invasive government and unintended consequences. As director of regulatory studies at the John Locke Foundation, Jo...