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.
Is Chesapeake Energy Corp. losing its grip as the drilling leader in Pennsylvania's Marcellus shale?
Examiner.com thinks so.
It reports that the Oklaohoma-based energy giant does not own any of the top 25 producing wells in Pennsylvania in the first half of 2012.
All of the top 25 wells are owned by either Cabot Oil & Gas Corp. or privately held Citrus Energy.
Chesapeake has drilled just 64 wells in Pennsylovania this year, due largely to low prices for natural gas.
It had averaged 235 wells in Pennsylvania in 2010-2011.
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