The Ohio Department of Natural Resources (ODNR) has ruled out a shallow injection well in northeast Ohio as the likely cause of a 2.1-magnitude earthquake recorded there last month, lifting a ban on operations and continuing its investigation of a deeper well nearby.
After the U.S. Geological Survey recorded the earthquake at the epicenter of two injection wells, located about 12 miles northwest of Youngstown, ODNR began an investigation that led it to believe those wells had triggered the seismic activity (see Shale Daily, Sept. 2). Earlier this month, the agency suspended operations at the wells, which are owned and operated by Ohio-based Avalon Holdings subsidiary American Water Management Services (see Shale Daily, Sept. 8).
ODNR decided to shut down the wells after reviewing data from an array of seismic monitors in the area. But after further investigation, ODNR spokeswoman Bethany McCorkle said the agency found no correlation between a shallower injection well at the American Water site and the earthquake.
"After analyzing all of the data obtained during the investigation regarding American Water Management Services injection well #1, ODNR concluded that with reasonable scientific certainty, injection operations at the shallower of the two wells was not related to the 2.1 seismic event that occurred in August," ODNR said. "Therefore, the chief of the Division of Oil and Gas has terminated the chief's orders suspending operations at that well."
McCorkle said the shallow well was drilled to a depth of 4,403 feet, while the deeper well extended 8,748 feet. That well remains closed while the investigation continues, she said.
The 2.1-earthquake, which caused no damage or injuries and could not be felt by those living in the area, is just the latest in a series of seismic events in northeast Ohio related to the oil and gas industry. ODNR was able to analyze data from the seismic monitors placed near the injection wells after it installed those devices because of a 4.0-magnitude earthquake on New Year's Eve 2011 in Youngstown that was linked to a separate injection site (see Shale Daily, Jan. 4, 2012)
The agency also issued new permitting requirements for horizontal oil and gas wells located within three miles of a known fault line after regulators determined that hydraulic fracturing operations at a Hilcorp Energy Co. site outside Youngstown had caused a series of small earthquakes in March (see Shale Daily, April 11; March 11).