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.
Ohio has issued 581 Utica shale permits, according to the March 23 update provided by the Ohio Department of Natural Resources.
That includes 281 completed wells, of which 77 are in production.
There are 34 drilling rigs working in Ohio.
A total of seven new permits were issued: four in Carroll County, two in Harrison County and one in Trumbull County.
The Trumbull permit is the first in Ohio for BP. It is for a horizontal well in Johnston Township.