A spate of earthquakes has been rumbling through northeastern Ohio for months, with the largest individual quake—magnitude 4.0—striking just before the end of the year. As quakes have rolled through regions not known from seismic excitement over the past few years—including Texas, Oklahoma, and Arkansas—residents, scientists, and activists have wondered whether the growing natural gas industry could have caused them. In the case of Ohio, the Columbia University scientist investigating the quakes says it’s almost certain there’s a connection.
Natural gas production is booming in America. To extract the gas, the industry has been using a technique, called hydraulic fracturing, which uses millions of gallons of chemical-laden water to help bubble gas up from the ground. “Fracking” has been a success for the gas industry: Natural gas is now cheap, plentiful, and reliable enough that it’s grabbing market share from coal. But the industry has had less success figuring out what to do with the wastewater the process generates. Companies often store the water in ponds, but people living near that contaminated water have fallen ill and documented increased exposure to fracking chemicals. So in Ohio, a company called Northstar Disposal Services was trying a different tactic, injecting the wastewater deep underground. It was this strategy that most likely caused the earthquakes there.
Any time huge quantities of liquid are poured down a hole and stored deep in the earth, they pose a risk of affecting the tectonic system below. A team of scientists from the U.S. Geological Survey have shown a fairly predictable relationship between the amount of fluid injected into the earth and the size of the earthquake that action could trigger. It’s not just the gas industry that has to worry about this side effect, either: Fluid-injection earthquakes are a potential hangup for clean coal projects and geothermal power, too. Most of the earthquakes connected to fracking fluid injection have been so minor that people can’t detect them, and some of the largest quakes in fracking areas may have nothing to do with fracking.
But fracking is causing earthquakes, a real problem that the gas industry has historically downplayed or denied. “To draw a correlation between earthquakes and oil and gas production, that just hasn’t happened,” one industry representative told the Dallas Morning News in 2008. And while that wasn’t entirely inaccurate at the time (the case for linking gas wells to earthquakes has grown stronger since then), responsible companies have an obligation to spend more time looking into the connection and less time being defensive.
Although natural gas has some advantages over coal and oil, the gas industry has repeated this pattern too many times. Fracking fluid wasn’t supposed to have diesel in it, until… oops, it turned out it did. It was impossible that fracking operations and wastewater disposal could ever leak chemicals into families’ water wells, until the Environmental Protection Agency showed that it had. Governors of gas-rich states, like New York’s Andrew Cuomo, see gas as a potential source for jobs and clean energy, as long as the gas can be extracted safely, and the gas industry is developing fracking methods that produce less waste and that could make the process less environmentally risky. But it’s hard for fracking opponents to trust that the industry can promise safe operations considering its history of trying to escape responsibility for potentially dangerous effects of its work.
Photo via (cc) flickr user danielfoster437
