FILE - In this June 25, 2012 file photo, a crew works on a gas drilling rig at a well site for shale based natural gas in Zelienople, Pa. As the oil and gas drilling method known as hyd

 

              FILE - In this June 25, 2012 file photo, a crew works on a gas drilling rig at a well site for shale based natural gas in Zelienople, Pa. As the oil and gas drilling method known as hyd
FILE - In this June 25, 2012 file photo, a crew works on a gas drilling rig at a well site for shale based natural gas in Zelienople, Pa. As the oil and gas drilling method known as hydraulic fracturing, or "fracking," mobilizes thousands around the country both for and against the process, industry and some environmental groups in Illinois have come together to draft regulations both sides could live with. Some hope that cooperative approach could be a model for other states. (AP Photo/Keith Srakocic, File)