As Northeast Ohio once again grapples with what caused a series of earthquakes in the region last week near a drilling site run by Hilcorp Energy Co., the public reaction has been mixed, tempered by the mild nature of the quakes and the likelihood of indefinite answers that aren’t expected anytime soon.

For many in Youngstown, and eight miles southeast in Lowellville, where 11 earthquakes ranging from 1.2-3.0-magnitude were recorded by the U.S. Geological Survey and researchers at Columbia University, the incident is oddly reminiscent of a 4.0 magnitude quake that shook the area on New Year’s Eve 2011.

In that instance, though, an injection well in Youngstown was to blame (see Shale Daily, Jan. 4, 2012). In March 2012, the Ohio Department of Natural Resources (ODNR) published a preliminary report that suggested injection operators had drilled too deeply into a layer of basement rock triggering the earthquakes. Just a few months later, researchers at Columbia University’s Lamont-Doherty Earth Observatory linked the injection well to as many as 109 tremors in the area between 2011 and 2012 (seeShale Daily, Sept. 6, 2013).

Today, the residents still talk about that event. And although a number of studies have been published in recent years linking injection wells in Texas and Oklahoma to earthquakes (see Shale Daily, Aug. 8, 2012; March 10), there remains considerable disagreement among public and academic communities about hydraulic fracturing’s (fracking) ability to induce seismic activity.

On March 10, ODNR shut down operations at a six-well pad at the Carbon Limestone Landfill in Poland Township after a 3.0 magnitude earthquake was felt in nearby Lowellville and some parts of Poland (see Shale Daily, March 11). The agency is currently conducting an investigation to determine what caused the quakes. A one-well pad was allowed to continue producing at the site, and ODNR officials later revealed that Hilcorp had been fracking one of its wells in the days leading up to earthquakes (see Shale Daily, March 12).

Since then, those on both sides of this state’s energy debate have emerged to make their claims about last week’s seismic events and fracking’s connection to such activity, with some vigorously questioning a link and others largely indifferent.

“I’ve heard one person talk about it. I wouldn’t go as far to say there’s no concern; I can’t say that with all the articles and everything the media has been saying,” said Lowellville Mayor Jim Iudiciani. “But nobody’s really bent out of shape, we’ll have to wait until they prove it, who the heck knows what caused it.”

Iudiciani said he didn’t feel the earthquakes. Lowellville treats the leachate from the landfill, but technically the wells are located in Poland. He said not many homes are located near the drilling site and, for the most part, Hilcorp has a solid reputation in the area, save for a coalition of local activists who are opposed to drilling in Ohio.

Poland Township Trustee Robert Lidle also said he didn’t feel the earthquakes, but heard others describe it them like a large truck rumbling by their house. No damage was reported, and “the tremor merely woke some residents up,” he said.

“As public officials, we’re keenly attuned to what ODNR is investigating. We’ve also been in contact with the general manager at the landfill and we’re keeping vigilant with respect to all that, without claiming that the sky is falling until we find out definitively what happened,” Lidle said. “By and large, though, there has not been an overwhelming amount of concern among residents at this juncture, at least nothing of significance.”

ODNR spokesman Mark Bruce said Tuesday the agency continues to gather and interpret data. The second well pad remains shut down and ODNR, Bruce said, has already met with Hilcorp several times. Bruce said it wasn’t yet clear when operations would be allowed to resume at the landfill and he wasn’t sure if the company had urged the agency to move the investigation along faster.

A source close to the company said no such appeal has been made and added that Hilcorp realized at the onset that there would be no timetable. Asked if it will be difficult for ODNR to prove a link between Hilcorp’s operations and the earthquakes, Bruce said he didn’t “have a good answer” for that question. “We haven’t finished looking at all the data and obviously any good answer depends on the information you have.”

Jeffrey Dick, who directs the Youngstown State University’s Natural Gas and Water Resources Institute, said it will be difficult for ODNR to prove such a link.

The area’s basement rocks, at about 9,000 feet underground, where faults originate in the region, have been questioned in the matter, but Hilcorp’s wells were drilled to a vertical depth of 7,900 feet, the company said. Dick said those faults sometimes run into sedimentary strata near the surface, but a lack of public seismic data makes it nearly impossible to determine if those exist at a shallow depth in Poland.

A large fault runs from Akron southeast to Suffield and into Columbiana County, which is south of Youngstown, but in the absence of seismic data, Dick said it was tough to say if that fault played any part in the quakes. He added that seismic activity is nothing new to the area.

In the late 1980s and early 1990s, a series of earthquakes rattled Ashtabula County in the very tip of Northeast Ohio along Lake Erie. Those quakes occurred along what’s known as the Akron Magnetic Anomaly, which is believed to be a linear trend, or fault line.  A Class I injection well was accepting industrial waste there at the time, but after the U.S. Environmental Protection Agency shut it down, the earthquakes continued to occur.

“You know it’s really hard to say what the cause could be. We have to assume in the absence of any drilling activity that these events might have happened anyway,” Dick said. “But since drilling was happening at the landfill, we also have to wonder if there is some association. In other areas there have been limited links between hydraulic fracturing and micro-seismic events.”

Dick said he’s most familiar with Ohio’s geology, and he believes there is nothing abnormal about it. He said if a map of all the state’s previous earthquakes were to be superimposed with one detailing where Utica Shale drilling is currently occurring, it wouldn’t suggest a link between the two.

“The knee jerk reaction of environmental activists and the public is to think this must be because of hydraulic fracturing operations,” he said. “You can’t approach it that way as a scientist and draw that kind of conclusion.

“The only thing that raises a flag to me is that there was more than one of these last week,” he added. “The first was a 3.0, and the others were aftershocks that did not have identical epicenters. It’s not uncommon to have aftershocks along faults, but additional activity could have forced those rocks to give a bit.”

Susie Beiersdorfer, a local activist with FrackFree Mahoning Valley and a geologist by trade, disagreed with Dick. “There’s definitely a correlation. We haven’t been saying that fracking caused the earthquakes, because we don’t want to go down the same road as the injection well in 2011,” she said. “You can’t tell the difference between what [ODNR] is saying and what the industry is saying about all this. We’re still waiting for a complete report from ODNR about the injection well that set off 109 earthquakes in 2011.”

Beiersdorfer said her coalition will continue to keep up the pressure on ODNR, public officials and the industry by keeping the issue in the public eye until a definitive answer is given. She said, if anything, that last week’s events are just one more reason why voters in Youngstown should vote to ban fracking in the city when they go to the polls in May (see Shale Daily, Dec. 31, 2013).

She also criticized ODNR for releasing misinformation about the complete status of Hilcorp’s operations in the days after the earthquakes. She said residents had to find out from themselves that a producing well was never shut down on the property as the agency had claimed.

To be sure, several studies in recent years have suggested a link between fracking and seismic activity. In 2012, the National Research Council said that stimulation doesn’t pose a big risk for triggering large-scale earthquakes, but minor ones instead (see Shale Daily, June 18, 2012). In 2013, After studying hundreds of thousands of fracking operations, the United Kingdom’s Durham University said that if any quakes were induced by stimulation they would likely go unnoticed (see Shale Daily, April 11, 2013).

Researchers in California cautioned that same year that stimulation could induce seismic activity in geologically active areas near faults (see Shale Daily, Jan. 18, 2013), while the British Columbia Oil and Gas Commission said in 2011 that fracking in the east-central portion of the Horn River Basin had triggered “a small cluster of low-level seismic events” (see Shale Daily, Oct. 11, 2011).

Beiersdorfer’s sentiments, and some of the science that supports them, worries Thomas Stewart, executive vice president of the Ohio Oil and Gas Association. He said there’s concern within his organization that the Lowellville earthquakes could tarnish the oil and gas industry’s reputation in Northeast Ohio.

“The problem with this is nobody has any perspective; it becomes hyperbole or whatever,” he said. “People continue to say that the area has never had an earthquake prior to drilling activity and that’s simply not the case. They have happened all the time at a low rate. I’m not being callous or crass, but the bottom line is nobody got hurt and we just need to let the experts do their work.”

Northeast Ohio is already somewhat on edge about the region’s place in the Utica Shale boom. Consol Energy Inc. has just two producing wells in Mahoning County, where last week’s earthquakes occurred. Chesapeake Energy Corp., meanwhile, has permits in the county, but they have no operations and they have expressed minimal interest in the region to date.

To the north, in Trumbull County, a BP plc unit and Halcon Resources have operations. But a recent decision by Halcon to temporarily suspend drilling in the area (see Shale Daily, March 5), and BP’s announcement that it hasn’t decided on its future in Northeast Ohio (see Shale Daily, Nov. 18, 2013) has led to widespread speculation by media that the industry is turning its back on the Northeast part of the state.

“It is what it is. The people who want to blemish the industry are going to say whatever they want,” Stewart said. “This industry has been operating in Ohio for 150 years and I think the track record is pretty darn good.”