Another Ohio community rocked by quakes
By Karl Henkelkhenkel@vindy.com
MARIETTA
Youngstown has become the poster city for potential injection-well-induced earthquakes.
But the Ohio Department of Natural Resources points to the success of 176 other injection wells throughout the state that have no history of inciting earthquakes.
Cue Washington County.
The Southeast Ohio county — an area that the ODNR has said is less prone to earthquakes than the rest of the state — hadn’t had an earthquake with an epicenter in the county before Oct. 24, 2010.
Since then, there have been four, with magnitudes ranging from 2.6 to 3.1 — large enough to feel, but small enough not to damage homes and infrastructure.
Sound familiar?
Like Mahoning County, Washington County shares another trait — brine-injection wells.
Injection wells are a disposal method for brine, a salty chemical byproduct of natural-gas fracking and oil drilling.
The ODNR has said it does not believe deep injections triggered the small quakes near Marietta, but that has not stopped the state environmental regulators from digging deeper.
The ODNR soon will monitor the area with four new seismographs — much as it did in Youngstown.
“We don’t believe it’s related to injection wells at this point,” Larry Wickstrom, state geologist, told The Vindicator. “We want to dispel any concern as best we can.”
A local geologist at Marietta College, however, maintains there could be a connection.
“Some of the earthquake events have occurred after an injection of water,” said Wendy Bartlett, instructor of geology at Marietta. “Most geoscientists believe that can happen.”
State Rep. Robert F. Hagan of Youngstown, D-60th, was alarmed when told of the ODNR’s additional monitoring near Newport Township, just east of Marietta.
“This is just blowing my mind now,” he said. “They are lying to us and covering it up without giving us all the information.”
Injection wells have been linked to — but not necessarily proved to have caused — earthquakes in Ashtabula County as well as the states of Arkansas, Oklahoma, West Virginia and Colorado.
WASHINGTON COUNTY
There are four active injection wells, owned by two companies, near the township of Newport, just north of the Ohio-West Virginia state line.
More than 1.3 million barrels of brine were injected into those wells during the first nine months of 2011, according to data from the ODNR. That amount is nearly 15 percent of the 8.7 million barrels of injected brine in Ohio during that period.
D&L injected about 352,000 barrels into its Youngstown well during the same period.
One barrel holds 42 gallons.
“Volumes for wells are fairly high for a few of them,” Wickstrom said, adding, “But it’s not that unusual.”
The wells are not as deep as the well in Youngstown. That well, on Ohio Works Drive, is 9,300 feet deep and could inject about 2,000 barrels of brine daily at pressures of up to 2,500 pounds per square inch before it was shut down Dec. 30.
All four Washington County wells pump water into the Clinton or Medina sandstones at depths between 6,900 and 7,300 feet.
Injection pressures reach about 1,900 psi, higher than a majority of pressures allotted at wells statewide.
The Washington County wells, however, inject near something called the Burning Springs Anticline, a well-known geological formation that Bartlett describes as “a fold that resembles an arch.”
Wickstrom said the anticline is a “thin-skinned structure,” different from the solid Precambrian bedrock into which the Youngstown well may have injected.
Ray Beiersdorfer, geology professor at Youngstown State University, said faulting can occur from an anticline and that movement along a fault line needs to occur to trigger an earthquake.
Brine can act as a lubricant along faults and cause geologic shifting.
The ODNR is aware of the anticline.
One Washington County earthquake, on Aug. 31, had an epicenter about 500 feet from one of the injection wells; an aftershock the same day had an epicenter about 20 miles from the same well site.
UNANSWERED QUESTIONS
The earthquake depths, much like the first nine Youngstown quakes, were about 3 miles.
That depth data, Bartlett said, is not precise because it came from only one seismic station, nearly 50 miles away in Athens.
Seismologists, including Michael Hansen of the Ohio Seismic Network, said it requires data from at least three seismic stations to determine precise earthquake depths.
The state plans to send one seismograph to Marietta College to monitor seismic events.
The ODNR this week hopes to implement the use of three portable seismograph stations, courtesy of the U.S. Geological Survey.
At this point, however, the state remains cautious, much as it did after the first handful of Youngstown earthquakes.
The ODNR also has purchased four portable seismographs valued at $10,000 each as part of a new “zero-tolerance policy.” If an injection well or wells are suspected of causing seismic events, the agency immediately will deploy the seismographs.
It maintains that Washington County and Mahoning County have little in common.
The ODNR said the earthquakes were not clustered around a well and the deepest injection formation is nearly a mile above the Precambrian bedrock, where preliminary data pinpointed the quakes.
“The body of evidence is not nearly as large in Marietta,” said E. Mac Swinford, assistant division chief, ODNR Division of Geological Survey.
CALL FOR CAUTION
Hagan says the new information about earthquakes makes him even more skeptical than he was after the Youngstown earthquakes.
“It just goes right to the base of what most of the critics have been saying,” Hagan told The Vindicator.
The office of Ohio Gov. John Kasich, who agreed with ODNR Director Jim Zehringer’s Dec. 31 decision to ban injection wells within five miles — now within seven miles — of Youngstown’s D&L well until the compilation of complete geologic data, deferred comment to the ODNR.
Hagan, who on multiple occasions has called for a moratorium on natural-gas fracking, oil drilling and injection wells, says he has greater concerns, not specifically about the industry, but about the overall process.
“Then we had the earthquakes and all of a sudden I am becoming a semi expert — baptism by fire,” he said.
“I am concerned about where they are putting these wells. I’m concerned about the earthquakes.
“I’m also concerned about government being honest to people.”
No comments:
Post a Comment