State geologists in Ohio have linked earthquake activity in the Utica Shale basin to hydraulic fracturing, for the first time, confirming the suspicions of activists pushing for drilling limits.
Drilling is being halted at the site of five small tremors in the Youngstown area last month, which prompted a state investigation into the link between drilling and quakes. The permit process will also be revised for drilling in earthquake-sensitive areas, requiring more monitoring and study.
ideastream's Tony Ganzer spoke with Mark Bruce, spokesman for the Ohio Department of Natural Resources.
Bruce: "After reviewing all of the available data, ODNR can draw a probable connection between hydraulic fracturing activities and seismic events that occurred in Poland Township back on March 10…people are going to ask 'probable connection, why we must say probable connection?' The depth of the recorded events vary greatly from one mile to four miles, to about the depth of the well, so we can't say 100 percent that they are connected, but there is enough evidence to indicate this probable connection."
Ganzer: "To stop the drilling in Mahoning County where we saw those quakes last month, is understandable, that's a reaction maybe, but to change the permitting process this seems like a bigger step. Why is this happening now?"
Bruce: "This is the first time that there has been a probable link between hydraulic fracturing and induced seismicity, so that's the first time this has happened. So as a result of that we wanted to look at what prudent and cautious steps could we take that apply to horizontal wells across the state. We feel this is an appropriate step to take."
Ganzer: "So there is still a distinction then between fracking and waste-water injection drilling?"
Bruce: "Yes, there is. Injection wells in the state…any permit we receive now, we review that permit as it relates to known faults already, and there may be seismic monitoring with injection wells as well, but what is new is how this relates to the horizontal production wells."
Bruce says about 400 drilling permits have been issued but not acted upon, and will be reviewed in light of the new requirements.
A seismologist with the U.S. Department of Interior said it's the first time seismic activity has been linked to Marcellus shale exploration that's swept the northeastern United States over the past several years.
