Quakes in Ohio Tied to Area Shale Operations

State says waste hit unmapped fault

Pittsburgh Post-Gazette
10 March 2012
By Don Hopey

Recent earthquakes along a previously unknown geologic fault line in eastern Ohio were caused by a deep-injection well used to dispose of wastewater from Marcellus Shale gas drilling, a state investigation has revealed.

The investigation by the Ohio Department of Natural Resources linked the earthquakes to "coincidental events," including the drilling and operation since December 2010 of the 9,184-foot-deep Northstar No. 1 disposal well owned by D&L Energy.

The well, also referred to by D&L Energy as the "Ohio Works," is five miles northwest of Youngstown. It received most of the brine and fracking wastewater it was injecting underground from Marcellus Shale drilling operations in Pennsylvania.

The ODNR's 20-page preliminary investigation report released Friday based its findings on evidence from seismic monitors, the locations of the epicenters of 12 minor earthquakes within one mile of the disposal well, and the discovery of a heretofore unknown fault in the underlying bedrock.

"We made the determination that, while it's difficult to induce seismic activity, the depth of this well reached a previously unmapped fault and there is a likelihood it lubricated the fault, resulting in seismic activity," ODNR spokesman Carlo LoParo said.

The earthquakes registered magnitudes of 2.7 to 4.0, rattling dishes in homes but causing no structural damage. A 4.0-magnitude earthquake has a seismic energy yield equivalent to detonating a small atomic bomb.

The first earthquakes occurred three months after the high-pressure injection of wastewater began. Several quakes occurred in December 2011, with the last and most powerful on New Year's Eve, less than 24 hours after state regulators asked the company to shut down the well.

According to the report's executive summary, although there is a history of seismic activity in Ohio before 2011, there was no recorded earthquake activity with epicenters in the Youngstown area. Also, no fault line previously had been mapped within the boundaries of Youngstown or Mahoning County, Ohio.

"The report's findings are not surprising. We thought all along that it was very likely the two were related," said Won-Young Kim, a professor of seismology, geology and tectonophysics at Columbia University's Lamont-Doherty Earth Observatory in New York, one of the earthquake experts Ohio hired last year.

"It's very rare that injection wells induce seismic activity, but it happens sometimes," Mr. Kim said. "When fluids encounter fault zones underground, it can trigger quakes. The difficulty comes because we don't know the subsurface geology very well."

Youngstown-based D&L Energy released a statement Friday critical of the ODNR for making conclusions without conducting any new tests at the Northstar well or waiting for the results of a company testing and research study under way at the site.

"It is unfortunate," according to the D&L statement, "that ODNR pre-empted a thorough search for information, opting instead for a politically expedient preliminary report that sacrifices true understanding for haste."

As a result of the earthquakes, Ohio has halted injection of wastewater in the Northstar well and development of four new wastewater-injection wells within 5 miles of the Northstar well.

The state also will implement new injection-well rules that ban future injection into Precambrian "basement rock," require state-of-the-art monitoring of well pressure and injection volumes, and require an electronic tracking system for drilling wastewater entering the state.

Terry Fleming, executive director of the Ohio Petroleum Council, noted that the investigation report acknowledges that "properly located injection wells do not cause earthquakes," but he also said the council supports the state's investigation and the proposed regulatory changes.

Susie Beiersdorfer, a geology instructor at Ohio State University and coordinator of Frackfree Mahoning Valley, a group opposed to shale gas drilling in eastern Ohio, said the organization favors a moratorium on new deep-injection well drilling until more can be learned about the state's geology.

"The state wants to restart the permitting process on these injection wells, but I think we need more information first about the risks to public health and safety," said Ms. Beiersdorfer, who lives near Youngstown and said she felt several of the quakes.

Since 1983, when Ohio started its deep-injection well program, about 10 billion gallons of oil and gas field waste fluids and brine have been disposed of in 177 Class II deep-injection wells.

Pennsylvania has six injection wells. There are also two well permits that have been approved but are under appeal and one application for a well in Venango County that is under consideration.

Kevin Sunday, a Pennsylvania Department of Environmental Protection spokesman, said the department will review the Ohio findings, but he noted that, unlike in Ohio, Pennsylvania allows the U.S. Environmental Protection Agency to have primary permitting responsibility for wastewater-injection wells here.

Mr. Sunday also said any seismic concerns about deep wastewater-injection wells are not transferable to deep shale gas drilling operations.

"The process of continually injecting wastewater under pressure into a deep disposal well differs from the relatively brief pressure used in a Marcellus Shale gas well," he said.

Jon Capacasa, water division director at EPA's Philadelphia Regional Office, said the agency is aware of the "concerns and associations" with seismic activity and deep-well injection operations. He said the agency takes precautions to avoid situations like the one that occurred near Youngstown by requiring companies seeking deep-well injection permits to identify known faults or geologic fractures within a mile of a proposed well site and limiting injection pressure.

"We like to keep a good buffer," Mr. Capacasa said. "Folks seem to be most concerned when there is a high concentration of injection well activity near a fault line. One well here or there is not likely to have that effect."

Don Hopey: dhopey@post-gazette.com or 412-263-1983.