W.Va. Provisionally Ready for Injection-Induced Earthquakes

The State Journal
4 January 2012
By Pam Kasey

A debate over the link between earthquakes and wastewater injected underground resurfaced over the holidays as dual Christmas Eve and New Year's Eve quakes capped off an extraordinary 11 tremors for the year near an injection well in northeast Ohio.

The Ohio Department of Natural Resources suspended activity at an active injection well at the center of the seismic activity northwest of Youngstown as well as at four nearby inactive wells, pending an investigation into a possible connection to the quakes.

At magnitudes ranging from 2.1 to 2.7, most of the tremors were too small to cause damage. Only the last, at 4.0, was strong enough to cause structural damage.

So how important is it for a state to respond to such a situation?

"We know from earlier studies, not necessarily in this area but out west, that man has produced earthquakes that are over 5.0 because of fluid injection," said Marshall University geologist Ronald Martino. "You're getting into a range where homes, highways, bridges, even dams can be damaged."

Is West Virginia ready for a similar situation?

Geologists: Injection Can Cause Quakes

Underground injection wells have been used for many decades to dispose of waste fluids. In Ohio, as in West Virginia, they are regulated by the state.

Injection wells have been connected with seismic activity in several isolated instances in the past: near Denver in the 1960s, in some other western states and, around the turn of the century, near Ashtabula  in northeast Ohio.

The use of injection wells has intensified in some locations over the past decade with the growing need to dispose of hydraulic fracturing flowback from horizontally drilled natural gas wells.

A series of hundreds of tremors in central Arkansas in 2010-11, culminating in a 4.7-magnitude quake in February 2011, led the Arkansas Oil and Gas Commission to close a fracturing fluid disposal well and to ban new wells in a 1,000-square mile radius.

Youngstown doesn't usually have earthquakes. The 11 quakes there dominated the list of 18 quakes over 2.0 originating in Ohio in 2011, according to the Ohio Seismic Network's database, while none of the 70 earthquakes listed for 2000-2010 occurred near Youngstown.

"Injection-induced seismicity, there's no question about that," said West Virginia University geologist Tom Wilson, a view affirmed by all of the geologists The State Journal contacted.

"Swarms" of earthquakes like the Youngstown incident can happen naturally, according to WVGES Director Michael Hohn.

But the contextual factors — the history of seismicity, the history of injection, the timeline, the depths — would help determine the likelihood of causation, Hohn said.

After Ohio DNR suspended activity at the wells near Youngstown, the Ohio Oil and Gas Association issued a statement Jan. 1 supporting the suspension for the "safety and peace of mind" for residents.

"We believe the situation in Youngstown is a rare and isolated event that should not cast doubt about the effectiveness or usage of … injection wells, which have been used safely and reliably as a disposal method for wastewater from oil and gas operations in the U.S. since the 1930s," said OOGA executive vice president Thomas Stewart in a media release.

One Ohio lawmaker said the response was not enough.

State Rep. Robert Hagan, D-Youngstown, told the Youngstown Vindicator that the state did not act quickly enough for public safety, and that he would renew his call for hearings on a bill he co-sponsored for a moratorium on injection wells.

W.Va.'s Approach

The West Virginia Department of Environmental Protection establishes a pressure permit limit for each injection well using an Environmental Protection Agency–approved method, according to DEP spokeswoman Kathy Cosco.

West Virginia has no formal plan for dealing with a situation similar to Ohio's, Cosco said.

However, it would first pursue a response that succeeded in 2010 following a series of eight quakes in Braxton County near a Chesapeake Appalachia
injection well, she said.

In that instance, Chesapeake had been permitted to inject at a pressure of 2,100 pounds per square inch, she said, and agreed to cut back. As the quakes subsided, the company, in cooperation with DEP, gradually ramped back up to the permitted injection pressure, without negative result.

"Do we know whether that was a direct correlation? We don't," Cosco said.

Better Instrumentation?

If an earthquake swarm were to start again near a West Virginia injection well, Hohn said, the well operator might have and be willing to share proprietary subsurface "ultrasound" data to help understand what's going on.

Also, "you could surround the area with instruments that could measure more accurately the location and depth," he said. "That will tell you if there's a single location and how close to the injection it is. We've looked into doing that for our state if something like this occurs."

Martino would like to see more permanent instrumentation.

"You need at least three to four stations surrounding the area," he said.

"Clarksburg, Sutton, Charleston, maybe Parkersburg, would be helpful. We could use better data, and that's something the state or federal government could do with a few tens of thousands of dollars."

Short of that, the Braxton County approach was an appropriate response, according to WVU geologist Tim Carr.

"It happens, and it's manageable," Carr said. "You either shut the well down or you reduce the injection rate."

It may indeed come up again in West Virginia.

The western part of the state has a larger number of deeper faults that may make it susceptible to this kind of activity, according to Wilson.

And Carr pointed out that, because Pennsylvania has a very low number of injection wells, those just outside its borders — that would include the Youngstown-area wells and, of the 13 commercial injection wells on West Virginia DEP's database, a couple in Monongalia County — draw business from a large area.