Geologists in Ohio have for the first time linked earthquakes in a geologic formation deep under the Appalachians to hydraulic fracturing, leading the state to issue new permit conditions Friday in certain areas that are among the nation's strictest.Quakes in Oklahoma, England and British Columbia have also been linked to fracking, but this is the first such finding in Ohio. As a consequence, Ohio is imposing new regulations.
A state investigation of five small tremors last month in the Youngstown area, in the Appalachian foothills, found the injection of sand and water that accompanies hydraulic fracturing, or fracking, in the Utica Shale may have increased pressure on a small, unknown fault, said State Oil & Gas Chief Rick Simmers. He called the link "probable."
While earlier studies had linked earthquakes in the same region to deep-injection wells used for disposal of fracking wastewater, this marks the first time tremors in the region have been tied directly to fracking, Simmers said. The five seismic events in March couldn't be easily felt by people.
The oil and gas drilling boom targets widely different rock formations around the nation, so the Ohio findings may not have much relevance to other areas other than perhaps influencing public perception of fracking's safety. The types of quakes connected to the industry are generally small and not easily felt, but the idea of human activity causing the earth to shake often doesn't sit well.
The state says the company that set off the Ohio quakes was following rules and appeared to be using common practices. It just got unlucky, Simmers said.
Under Ohio's new permit conditions, all new drilling sites within 3 miles of a known fault or seismic activity of 2.0 magnitude or higher will be conditioned on the installation of sensitive seismic-monitoring equipment. Results will be directly available to regulators, Simmers said, so the state isn't reliant on drilling operators providing the data voluntarily.
If seismic activity of 1.0 magnitude or greater is felt, drilling will be paused for evaluation. If a link is found, the operation will be halted.