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.
Public health professionals say that Pennsylvania's new impact fee law signed by Gov. Corbett last week could hurt the delivery of health services to injured workers and residents living near gas-drilling sites.
The legislation allows drillers to withhold information on the chemicals used to hydraulically fracture or frack the wells, if the company deems them proprietary, or a trade secret. That would include the chemical's identity and the concentration level.
A provision allows health provicders access to the information in order to treat a patient but it requires health-care workers to signa confidentiality agreements that allow the health-care professionals to use the information only to treat the individual patients.
That runs counter to widely held medical ethics and is wrong, says Dr. Jerome Paulson at George Washington University.
Click here to see an account of the debate.