Oil and gas activity in Kansas is likely to blame for the state's recent spate of earthquakes, geologists said this week. Their finding adds to the mounting evidence across the country that injecting wastewater from oil and gas wells can cause seismic shocks in typically stable areas.
“I think [researchers] do see a correlation between the increased number and volume of disposal wells in south-central Kansas and seismic activity,” Rex Buchanan, interim director of the Kansas Geological Survey, told the state’s House Energy and Environment Committee earlier this week, according to local media reports.
Asked whether he believes there is a “reasonable probability” of a link between tremors and injections, Buchanan said, “I think it’s reasonable to say that’s the direction we’re going. We’ve had a number of meetings with the U.S. Geological Survey and folks from the academic community around the country, and that’s sort of where the attention is going at this point.”
Wastewater is a chemical-laden byproduct of both conventional oil drilling and modern techniques like hydraulic fracturing, aka fracking. As U.S. energy production has soared in recent years, so have volumes of wastewater injected into geological formations as part of the production process. While most injections do not cause earthquakes, they can if the water is inserted near fault zones or in particularly hefty volumes, according to U.S. geologists. Arkansas, Oklahoma, Ohio and Texas have all seen an acceleration of earthquakes lately as fracking enables energy companies to tap more fossil fuel reserves.
In Kansas, only 34 earthquakes with magnitude 2.5 or higher occurred in the state between 1977 and 2012, according to data provided to the House committee and cited by Kansas newspapers. Since 2013, Kansas has seen 115 tremors of that size or greater.
The rise in tremors is especially acute in Harper and Sumner counties, which are both southwest of the Wichita. From 1977 to 2012, the two counties saw only two quakes with magnitudes greater than 2.0. Since 2013, they’ve seen 138 tremors. At the same time, oil and gas production has soared in both counties along with the number of wastewater disposal wells.
“There has been a tremendous increase in the amount of water being produced, as well as in the amount of oil,” Ryan Hoffman, who directs the Kansas Corporation Commission’s conservation division, told lawmakers Monday.
Buchanan of the state geological survey said the agency needs about $500,000 to increase its seismic monitoring. John Carmichael, a Democratic state representative, expressed his support for additional funding at the hearing. “There’s always the possibility that a catastrophic event will occur particularly related to injection wells,” he said. “That would be devastating to the oil and gas industry, not to mention the lives and property involved.”
In Oklahoma, a 5.7-magnitude tremor in 2011 cost the small town of Prague nearly $1 million in damages. Federal scientists have since confirmed that wastewater injection wells were likely the cause of the earthquake. At least one Prague resident, Sandra Ladra, is suing dozens of energy companies over injuries she says she sustained during the quake. The Oklahoma Supreme Court is set to decide soon whether at least two companies should be held financially responsible for Ladra's injuries. If judges rule in Ladra's favor, it could alter the way energy companies do business in Oklahoma, Climate Progress, a liberal-leaning blog, noted Monday.