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.
Last March, officials in the Ohio Department of Natural Resources told Ohio legislators that 250 natural gas-oil wells would be drilled in the Utica shale in 2012.
That hasn't happened, the Columbus Dispatch reports.
To date, 165 wells have been drilled and another 22 are in the works in Ohio.
The drilling pace slowed in part because of low natural gas prices and the need for pipelines and processing plants in eastern Ohio, said Tom Stewart of the Ohio Oil and Gas Association.
The state is getting a steady stream of permit requests for drilling.
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