Fracking and seismic activity
By Jim Hagerty
While the U.S. Geological Survey shows earthquakes caused by hydraulic fracturing (fracking) are less severe than naturally occurring quakes, their frequency is becoming a more-than-poignant point of contention.
The U.S. Geologicial Survey experts analyzed 11 induced earthquakes from 2011-2013 and categorized the severity of their ground tremor intensity as low. The USGS concluded that earthquakes from fracking shake the ground less than natural tremors of the same magnitude. According to seismologist Susan Hough, fracking-induced quakes lose energy approximately 6 miles from their epicenter. The loss occurs because injected water lubricates the fault, causing it to slip, Hough told Bloomberg.
The report, Vol. 104. No. 4 of Hough’s “Bulletin of the Seismological Society of America,” was released Aug. 19, the same day Oklahoma was shaken by 20 earthquakes, each linked to fracking. The quakes were below a magnitude 3, although a 4.3-magnitude quake shook the city of Guthrie, Oklahoma. The tremor was reminiscent of a 5.7-magnitude, fracking-related quake that damaged several homes in Prague, Oklahoma, almost three years ago.
While Hough’s “Bulletin of the Seismological Society of America” seems to favor the gas and oil industry, it appears equally clear that fracking causes earthquakes, regardless of their intensity.
Wednesday, Aug. 20, on the Diane Rehm Show, a leading energy company president was joined by a Natural Resources Defense Council analyst and Pro Publica reporter to discuss the ills of fracking and its regulations. The panel wasted little time tackling the link between fracking, earthquakes and potential groundwater contamination.
Abrahm Lustgarten, of Pro Publica, told Rehm not only were there 20 tremors in Oklahoma a day before, hundreds have been reported there in the past couple months. The quakes are unique because of how they manipulate faults.
“The waste injection wells are a place where they inject basically millions of gallons of fluid underground and weighs a whole lot,” Lustgarten said. “It upsets the stability underground and can cause the faults that exist to move when they wouldn’t have moved otherwise. And there have been a number of earthquakes, some as high as 5.6 (magnitude).”
Hough sampled 10 tectonic earthquakes from 2002 to 2011. Natural quakes had average magnitudes between 4.0 and 5.8. Induced quakes averaged between 3.9 and 5.7, but have not caused widespread devastation.
The frequency of induced earthquakes and their effects on natural and man-made landscapes is a growing concern.
“The U.S. Geological Survey issued a report that in the eastern and central United States, there used to be about 20 earthquakes a year, and now, on average, there are more than 100 that are of a magnitude of 3.0 or greater,” said Amy Mall, an analyst with the Natural Resources Defense Council. “These can cause damage to structures. And there’s also potential damage to gas wells, which there’s still a lot more science that needs to be done. But, at this point, the science does seem conclusive that at least some of these are due to oil and gas initiatives.”
Mark Boling, president of V+, a division of Houston-based Southwestern Energy Co., told Rehm the difference between hydraulically fractured wells and deep injection wells is at the center of potential dangers.
“So far, except for one case over in the U.K., where there was significant volumes of water in a frack job that was pumped directly into a fault, there haven’t been any cases where hydraulic fracturing has actually caused any seismic activity,” Boling said.
What has the most potential to spark an earthquake, Boling claims, are problems with disposal wells, which during the fracking process, become filled with wastewater. For wells to spark seismic activity, three conditions must be met. First, force must be applied on both sides of a fault to get it to move. That can be a difficult task, as friction keeps a fault in place.
“Then, you have to have a disposal well that is constructed close enough, both vertically and horizontally to that fault so that the fluid pressure, when it’s injected, can actually be transmitted to the fault’s surface,” Boling said. “The third thing is that the water that is injected in the well is injected at a high enough rate and enough volumes that that fluid pressure is great enough to overcome the frictional forces. You will have movement along the fault.”
In Texas, the Railroad Commission is urging lawmakers to require drilling companies to research faults and determine how much water can safely be injected before fracking commences in a given area.
“Because they did an experiment, many, many years ago in Colorado to show that you could actually control the earthquake activity just by increasing or decreasing the amount of water,” Boling told Rehm. “So, that tells you that if you could reduce the rate at which it is pumped, or the volume, you can decrease or eliminate that activity.”
State energy departments and the federal Environmental Protection Agency (EPA) have been researching water-induced earthquakes for the good part of the last six decades, yet some of its regulations have never applied to gas and oil companies.
“With knowledge that this risk existed, the oil and gas industry has been exempted from having to do the sort of research that Mark’s describing, may now become commonplace in Texas,” Lustgarten said. “And they did that with the EPA’s consent, and the EPA also has really failed to incorporate knowledge of this risk into their regulations. It’s something they’re starting to look at now, but could have done years ago.”
Gas oil and gas exemptions were popular on the heels of the 1970s Energy Crisis and the ’80s glut that had the country floating on a massive crude oil surplus.
“Congress exempted the oil and gas industry from our rules that govern hazardous waste as a favor to the industry,” Mall said. “And, unfortunately, even though the evidence has been mounting since the 1980s that this waste can be quite toxic and there are many risks, including the seismic risk, Congress has not closed that loophole. And the GAO (U.S. Government Accountability Office) found, in particular, that it — when you come to this underground injection, specifically, the rules the EPA has put out, haven’t been updated since 1980. So, (the) EPA could be doing more within the existing law, but Congress really is the one that created this loophole.”
The loophole, as it was during the onset of Reaganomics, is still knotted by future profits lawmakers are hesitant to disrupt, especially if it means tapping the EPA for new regulations.
New EPA guidelines wouldn’t have to be complicated, something Boling calls “smart regulation.”
“To me, [smart regulation] is just effective risk management,” Boling said. “We’ve identified the risk of induced seismicity. And to put this into proper context, however, I think it’s important to know that of the 150,000 permitted UIC (Underground Injection Control) wells in the country, we’ve had issues with a handful of them. Now, that doesn’t dismiss it as not an important issue.”
With well integrity comes protecting groundwater, and the lack of standards to which gas and oil giants are held. For example, the industry has permission to intentionally pollute more than 1,000 aquifers (layers of surface material that contains drinking water). As the law stands, drilling into the material for fracking can be done without regulation; drilling companies are exempt from specific aspects of the Safe Drinking Water Act.
Boling added: “I think one of the problems the industry has had from the very beginning back to the gas land days, when we had the vision of the flaming faucets, what I would say was probably a better coal bed methane well than a water well, is you have a problem where we, as an industry, did a very poor job of describing how important well integrity is. All we would say, ‘We’ve been doing this for 60 years without a problem, blah, blah, blah, And hydraulic fracturing couldn’t possibly cause this.’”
The Diane Rehm Show airs locally from 9 to 11 a.m., on WNIJ-AM.
From the Sept. 3-9, 2014, issue