The Railroad Commission of Texas (RRC) was scheduled to hold a town hall meeting Thursday night in Tarrant County to discuss seismic occurrences in the Barnett Shale in North Texas, a phenomenon which some scientists have linked to wastewater injection wells.

Meanwhile, several communities in the Eagle Ford Shale in South Texas are raising concerns that additional injection wells there could not only compromise scant water resources but cause similar earthquakes as well.

RRC spokeswoman Ramona Nye told NGI’s Shale Daily on Thursday that the agency’s chairman, David Porter, would host the evening meeting at Azle High School auditorium in Azle, TX. She said Porter would listen to residents’ concerns about the earthquakes and outline a strategy to address the issue. Nye said other state and local officials would be in attendance.

In August 2012, researchers with Proceedings of the National Academy of Sciences of the United States (PNAS) said there was a link between dozens of small earthquakes in the Barnett and wastewater injection wells (see Shale Daily, Aug. 8, 2012).

But one year later, the lead researcher for the PNAS study — Cliff Frohlich, a geophysics professor the University of Texas at Austin’s Institute for Geophysics — said the majority of 62 probable earthquakes in the Eagle Ford were caused by fluid extraction from oil and gas drilling, not from wastewater injection wells (see Shale Daily, Aug. 28, 2013).

And in May 2013, three researchers from the Southwest Research Institute in San Antonio (SWRI) — Paul Bertetti, Ronald Green and Alan Morris — told the National Groundwater Association that the greatest threat from hydraulic fracturing (fracking) is wastewater injection wells.

“Threats to successful disposal of the liquid wastes are encountered when the targeted disposal horizons are former oil and gas formations into which previous exploration and production wells had been drilled, but not properly abandoned,” the SWRI researchers said, according to an abstract from their presentation.

The SWRI researchers added that the risks could be mitigated by avoiding injecting wastewater into depleted oil and gas formations, expanding the inspection area around an injection well to identify improperly abandoned wells, and developing a comprehensive database to catalog incidents from injection wells.

Frio County Commissioner Richard Graf told NGI’s Shale Daily that last March the county board passed a non-binding resolution opposing all future injection wells in the county.

“There’s not a whole lot we can do about it, other than make sure that we protest each well,” Graf said Thursday. “According to the RCC, if they meet the criteria and they do what they’re supposed to do, then there’s not a whole lot we can do other than oppose them.

“All of us know that with the oil business, you’re going to have to do something with the waste. And that’s what you do with it — inject it back into these injection wells. That’s fine. But what we’re concerned about is the RRC’s lack of personnel to monitor these injection wells properly.”

Graf said the RRC and the Texas Commission on Environmental Quality try their best to respond to complaints, but both agencies have limited resources. He said further study on injection wells was warranted, but it did not appear to be a high priority with regulators.

“There’s so many more [wells], and so much more of the waste now with fracking, that it’s a concern to us,” Graf said. “We’re not saying that there’s something wrong with it, but we think that a lot more people should be concerned about it. We’re two and a half, three years into this and our concerns are growing.”

Graf said Frio County currently has 20 operating injection wells, with another three permitted and under construction. The new wells are expected to be online in April. He said another four injection wells are permitted, but construction hasn’t started yet.

“Personally, I’m not concerned with the newer wells as much as I am these older injection wells that have been here since the 70s and 80s,” Graf said. “Once that’s compromised, we don’t know where that [waste] is going to go.

“We’ve met with RRC officials and they’ve told us that [injection well operators] want to be here because of the geological content of Frio County. We understand that. We were told that 20 years ago.”

Several studies have been conducted to try and determine the link, or lack thereof, between injection wells and seismic activity (see Shale Daily, July 15, 2013; April 11, 2013; Jan. 18, 2013).

In Arkansas, landowners have sued to stop wastewater injection wells, and the state’s Oil and Gas Commission established an injection well moratorium area following earthquake swarms in the region (see Shale Daily, Oct. 9, 2012; July 29, 2011). Injection wells have also been blamed for quakes in Oklahoma and Ohio (see Shale Daily, Oct. 25, 2013; Sept. 6, 2013). The U.S. Environmental Protection Agency is also studying the issue (see Shale Daily, July 29, 2013).