Here's Friday's statement by Tom Stewart, executive vice president of the Ohio Oil and Gas Association:
"Today, the Ohio Department of Natural Resources confirmed, in a preliminary report, our belief that the recent seismic activity in the Youngstown area was associated with a previously unknown geologic factor, in this case, an unmapped fault near a Class II injection well.
"Class II injection wells, which are heavily regulated at the state and federal level, have provided Ohio with a safe and reliable disposal method for wastewater from oil and gas operations for more than 30 years. In 1985, recognizing the value and proficiency of injection wells, the Ohio General Assembly mandated Class II wells as the only acceptable wastewater-disposal method in the state by House Bill 501.
"We plan to thoroughly review the new regulations proposed by ODNR and strongly urge the public and state officials to not allow a rare and isolated event to diminish the excellent service record of Class II injection wells in Ohio."
Chesapeake Energy Corp,the Oklahoma-based firm is the No. 1 driller in Ohio.
Rig Count Interactive Map by Baker Hughes, an energy services company.
Shale Sheet Fracking, a Youngstown Vindicator blog.
The Ohio Environmental Council, a statewide eco-group based in Columbus.
Earthjustice, a national eco-group.
People's Oil and Gas Collaborative-Ohio, a grass-roots group in Northeast Ohio.
Concerned Citizens of Medina County, a grass-roots group.
No Frack Ohio, a Columbus-based grass-roots group.
Fracking: Gas Drilling's Environmental Threat by ProPublica, an online journalism site.
Pipeline, blog from Pittsburgh Post-Gazette on Marcellus shale drilling.
Allegheny Front, environmental public radio for Western Pennsylvania.