Another reason Dallas should be very cautious about gas drilling:
EPA says Parker County homes at risk of explosion after aquifer near ‘fracked’ gas wells is contaminated
by Randy Lee Loftis / The Dallas Morning News (Dec. 7, 2010)
Natural gas from drilling that used the controversial practice of hydraulic fracturing has contaminated a drinking-water aquifer in Parker County, putting two homes at risk of explosion and triggering a federal emergency order, the Environmental Protection Agency’s regional chief said late this afternoon.
The EPA ordered Fort-Worth based Range Production Co. to take steps to protect the families and water supplies after the Texas Railroad Commission, which regulates natural-gas drilling, failed to act, EPA Regional Administrator Al Amendariz said….
The gas wells were drilled using hydraulic fracturing, or fracking, in which millions of gallons of water mixed with chemicals is injected deep underground under high pressure. The pressure fractures the tight shale formation and releases trapped natural gas. In the last five years, fracking has turned North Texas’ Barnett Shale field into the nation’s biggest natural gas area, with tens of thousands of wells drilled….
Required casing and cement that line the gas well might have failed, letting gas escape into the aquifer, he said. It’s also possible that drilling struck a geological fault or an old gas well, he said. The extent of contamination isn’t known. Range must identify the affected area under the EPA order.
“We know they’ve polluted the aquifer,” Armendariz said. “We know they’re getting natural gas in there. We don’t know yet how far it’s spread.”…