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 now approved 596 Utica shale permits, of which 293 wells have been drilled.
Those totals, released by the Ohio Department of Natural Resources, are through April 6.
A total of 81 of those wells are in production.
A total of 32 drilling works are working in Ohio.
The nine new permits are: Belmont County, three; Carroll County, three; Harrison County, two; and Mahoning County, one.
In addition, Ohio has approved 20 permits for Marcellus shale wellos, of which 10 have been drilled.