By jeanne starmack
Many resources are renewable, but groundwater is not one of them.
If groundwater is tainted by pollution and an aquifer is ruined, it will recover — but not in our lifetimes, said John Stolz, a microbiologist and director for the Center for Environmental Research at Duquesne University in Pittsburgh.
Aquifers can take hundreds or thousands of years to recover, Stolz said. Even though aquifers are replenished with fresh rain, toxins bind to the rocks in the ground and stay there, he explained.
Along with the obvious danger to surface water from spills or leaks at Marcellus Shale gas-well sites, the specter of ruined aquifers has critics of hydraulic fracturing calling for a moratorium on the practice.
To reach the Marcellus Shale between 5,000 and 8,000 feet underground, gas companies drill through aquifers close to the surface and other layers of rock. Once a vertical well is drilled, horizontal drills bore through the shale.
Millions of gallons of fluid made up of water, sand and chemicals are then injected at high pressure to fracture the shale and release the natural gas there. Fluid that comes back to the surface is disposed of in deep injection wells in Ohio.
But much of it remains underground.
The aquifer is separated by thousands of feet of hard rock layers on top of the shale, so fracking fluid will not migrate upward to an aquifer, proponents of drilling say.
Dave Kern is area manager for Kroff Well Services, which makes fracking fluid, and a member of the Marcellus Shale Coalition.
“I’m a chemist and an environmental scientist from Pitt (University),” he told the audience at a panel discussion on fracking in New Wilmington on Feb. 15. “I have a big vested interest in making sure this is done right.”
Kern said wells also are cased in multiple layers of cement and steel to ensure protection of an aquifer.
But that all-important casing, fracking’s critics say, isn’t fail-proof. It can shrink and crack.
That can allow methane gas and toxic chemicals in frack fluid to migrate into aquifers, they say.
Range Resources, which developed wells in Washington County, Pa., had 15 instances of inadequate or improper casing noted among 189 violations on record with the Pennsylvania Department of Environmental Protection since 2006.
Rex Energy, which residents in a Butler County neighborhood suspect contaminated their well water, had a casing violation in 2010.
Rex has denied its gas wells have had an impact on groundwater in the neighborhood, and the state DEP has also said there is no evidence drilling has impacted the water there.
Range Resources spokesman Matt Pitzarella said the well-casing violations haven’t impacted groundwater, and said that proves regulators are doing their jobs.
Critics of fracking also are alarmed that no one outside of the companies that make fracking fluid is allowed to know what chemicals are in the mix. The companies say their mixtures are proprietary. Companies can voluntarily disclose chemicals they use on a website called fracfocus.org.
Kern said 95 percent of the mixture is sand and water. It’s the other 5 percent, which could contain toxins, that worries critics.
Kern said there will be more disclosure now in the industry, and state law requires disclosure of fracking chemicals to the DEP, emergency responders and health professionals who need the information in an emergency. Under the law, the companies’ fracking fluid recipes are still protected.
Pitzarella said Range does not use toxins in fracking, and he believes that the use of them is an older practice that is going by the wayside in the industry.
Kern told The Vindicator his company’s fluid contains none of the toxins benzene, a carcinogen that used to be used in paint thinners and spot removers; toluene, a benzene-derivative used in solvents; or xylene and glycol ethers, also used in solvents.
All of those chemicals, however, are listed as possible ingredients of frack fluid, along with many other chemicals, on the DEP’s website.
Besides a failed well’s being a conduit for fracking fluid, that fluid could also migrate upward through fissures and faults, Stoltz said.
Even without the presence of fracking chemicals, drilling can ruin well water, he said. He has investigated problems at homeowners’ wells in Butler County near the Rex Energy developments.
He said it’s very possible that natural contaminants in water, such as arsenic, were made worse there.
Drilling can redirect an aquifer, he said, and that can result in a loss of water. Kim McEvoy, one of the Butler County homeowners, says she only gets a few gallons of water at a time from her well.
Stoltz said that it is possible to remediate tainted well water.
“People would have to spend $10,000 for a water treatment system, and at whose cost?” he said.
Stolz said homeowners should get their well water tested before drilling begins in their neighborhoods. He said tests cost from $400 to $1,200, and people should use one of 72 testing companies approved by the DEP.