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.
A new study in the journal Nature indicates that the drought and hydraulic fracturing or fracking is creating additional stress on water supplies, particularly in agricultural zones.
"Groundwater demand is exceeding supply and is turning our rural areas into sacrifice zones," said Wenonah Hauter, executive director of the group Food & Water Watch.
Fracking is also diverting water that is needed to grow food, she said in an Aug. 9 statement.
"Drilling and fracking is not only a threat to water quality. It also uses massive amounts of water, removing much of the water from the water cycle altogether," she said.