By Brandon Hollingsworth
http://stream.publicbroadcasting.net/production/mp3/wkno/local-wkno-981999.mp3
Knoxville, TN – A process for natural gas drilling known as hydraulic fracturing is rife with controversy. People from Pennsylvania to Wyoming complain it taints groundwater and causes health problems. Hydraulic fracturing is also taking place in Tennessee, but the results are far different. With environmental groups on one side and gas drillers on the other, it can be tough to get reliable information. Brandon Hollingsworth takes a closer look at hydraulic fracturing, or "fracking."
On a ridge in Campbell County sits a big green cylindrical tank. It's connected to some gauges and some pipes that run from the tank into the surface of the Earth. The equipment clicks and hisses, but it's the only sound around for miles. Fracking is a method of extracting natural gas from shale deep underground - in Tennessee, it's called the Chattanooga Shale. Fluids are sent down a well at high velocity and pressure. That force forms cracks in the rock layers, freeing up pockets of natural gas.
At least, until I show up with former Tennessee Oil and Gas Association president Scott Gilbert.
Scott Gilbert, former president of Tennessee Oil and Gas Association explains that a sand-and-water mixture "with some nitrogen" is injected into the shale. He says it increases production, and "makes the wells economical to drill."
That, Gilbert says, is the key term - economic viability. Fracking works in areas that have long been known to contain natural gas, but there haven't been effective ways of drilling for that gas without losing a lot of money. Making the process even more productive is a newer technique, called horizontal drilling.
"Essentially, the more horizontal hole you have exposed to the wellbore, the better the chance for increased production," Gilbert says. "The more gas the well will produce."
That's fracking on paper. In practice is where it gets a little hairy.
A fight is brewing over regulation of the practice in Tennessee. There are 600 gas wells operating in six Tennessee counties, all on the Cumberland Plateau. Of the 600, 95 are the horizontal wells anti-fracking groups worry about the most. William Wilson is a member of the conservation group United Mountain Defense.
"The kind of fracking that's going in Pennsylvania, and in the movie Gasland, is not happening here." Wilson continues, "But the problems I've seen are that there is no real information for the citizens of Tennessee. So the fracking practices that are going on here, we know very little about."
Environmentalists feel the Tennessee Oil and Gas Association and the Department of Environment and Conservation aren't doing enough to make gas companies disclose what kinds of chemicals are being used in the fracking process. Renee Hoyos is president of the Tennessee Clean Water Network.
"So I wonder why there's all this resistance to having these regulations. If all they have to disclose is water, why are they fighting so hard to not have a disclosure regulation?" Hoyos continues, "Because, very possibly, the technology will change and they will want that freedom to pump whatever they want into their wells. To increase extraction."
There's also concern fracking fluids used could contaminate groundwater aquifers on the Plateau. But those aquifers typically reach a depth of only a few hundred feet. The depth of drilling in the Cumberland Plateau is around 3,000 feet. And there are layers of impermeable rocks geologists call confining units. They restrict the flow of water - and natural gas, making cross-contamination from a gas well unlikely. Surface contamination is a possibility, but a low one, says T-DEC environmental scientist Jonathan Burr.
"Most of the fracturing here now is done with just nitrogen gas and very little water, so there is no product, or wastewater, produced at all. So little is produced, that it hasn't really been a problem for us," Burr said.
But Burr says that doesn't mean the environmental requirements for gas drillers couldn't be tightened.
"I cannot tell you with great certainty exactly how much is produced here, here and here...and where every drop of it went and how well it was tested first. We need to have a little bit better tracking. And so we're looking into that right now."
A recent update to the state's oil and gas regulations contained no mention of fracking. The Tennessee Department of Environment and Conversation says it's now in the process of meeting with stakeholders on all sides of the issue. In an e-mail, T-DEC says it's working to address horizontal drilling and fracking from a regulatory standpoint. There's no timetable for completion of those meetings.