Last month, the PennEnvironmnent Research and Policy Center documented 3,365 violations by Pennsylvania natural gas operators in the Marcellus shale over the last four years.
Between 2008 and 2011, energy companies drilled 4,596 new wells in Pennsylvania.
The non-profit center, with offices in Philadelphia and Pittsburgh, called on state leaders to halt drilling until operators can prove that the drilling will be done safely and not a threat to human health or the environment.
Click here to access the report.
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.