Not yet a county concern[ By Adam Broderick ]
Two weeks ago the Denver Post published an article citing new findings from a U.S. Geological Survey (USGS) study connecting practices related to hydraulic fracturing, or fracking—the stimulation of the release of oil and gas from deep shale rock beds—to increased earthquake frequency.
According to geologists, “earthquakes of magnitude 3 or greater are 100 times more likely now than in 2008 in regions of Colorado and seven states that are hotbeds for oil and gas drilling.”
Some locals may be worried that seismic risk is growing in Gunnison County, mainly due to recent developments in the natural gas market and the county’s approval of some new water storage wells, a.k.a. fracking pits, but local officials say there is no evidence of fracking-induced quakes in the area.
County manager Matthew Birnie says fracking has been practiced here for several decades but there is almost no current drilling activity in the county due to the poor market conditions for natural gas. “The biggest issue isn’t actually fracking itself, but the re-injection of water,” he added.
USGS scientists who conducted the study confirmed Birnie’s theory. They report the increase in seismicity has been found to coincide with the injection of wastewater in deep disposal wells. “[The problematic] wells inject at many thousands of feet below the surface and can interact with natural faults in the vicinity that are primed to slip in earthquakes,” said Bill Ellsworth of the USGS Earthquake Science Center.
But the storage facility recently approved for development close to Paonia that has some locals talking seismicity is supposed to house long, shallow pits—in fact, only about one foot deep by 63 football fields long and wide, collectively.
“Shallow pits won’t have any potential to induce earthquakes,” Ellsworth said. “The real issue is disposal by injection of very large volumes of water that comes to the surface with a much smaller volume of oil.”
Birnie says his understanding is that those shallow pits will greatly reduce the amount of produced water that is re-injected into the ground. That could in turn reduce seismic activity.
“I don’t believe the pits have been constructed,” says Birnie, “because there is almost no current drilling activity in the county due to the poor market conditions for natural gas.
“For what it’s worth, I have yet to hear from anyone who actually lives in the Big Muddy drainage who expresses these ‘concerns’,” Birnie says. Plus, that’s not fracking. That’s just disposing of the water from fracking jobs where it was taken.
Still, fracking takes place in the North Fork. Birnie confirms produced water has indeed been reinjected at job sites in the area. He also says the USGS “hot spot” designation is based on the area’s geology and its likelihood of being negatively affected by these practices, not primarily the history or prevalence of fracking in the area.
So is there legitimate reason for local concern?
The Post article included a map with noted “hot spots,” but the five areas in Colorado that the USGS put on the map weren’t anywhere near Gunnison County. They were closer to Denver and the plains.
In northern and eastern Colorado and other states such as Oklahoma and Texas, where fracking is most commonly practiced, the USGS says the number of earthquakes has increased dramatically over the past few years. Results from the study are posted on the USGS website.
According to the study, “Between the years 1973-2008, there was an average of 21 earthquakes of magnitude three and larger [per year] …this rate jumped to an average of 99 M3+ earthquakes per year in 2009-2013, and the rate continues to rise. In 2014, there were 659 M3 and larger earthquakes.”
Spokesman for the state of Colorado Todd Hartman says the state reviews industry sites for seismic potential before issuing permits, and natural resource officials are in close communication with relevant state, federal, interstate and academic experts. Birnie says, “Absent any evidence that this is an issue in Gunnison County, this is likely an issue that we would follow the state’s lead on.”
So it seems we’ll just have to wait and see. For now, here’s a fun fact from that same Post article: “Last June, the Colorado Oil and Gas Conservation Commission ordered NGL Water Solutions to stop injecting wastewater into a 10,770-foot well near the Greeley-Weld County airport after a 3.2-magnitude earthquake. Shaking stopped.”