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.
The deadly Quebec train accident is bringing new scrutiny to the growing use of rail to carry oil long distances and prompting worries that the higher volume being moved by rail will mean more accidents.
Rail proponents saying moving oil by rail is safe, but critics argue that pipelines are safer.
But it's no secret that more crude is moving by rail from North Dakota to eastern refineries.
Click here to read the full story from the Houston Chronicle by Zain Shauk and Jennifer Dlouhy.