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.