By Siobhan Hughes Of DOW JONES NEWSWIRES WASHINGTON (Dow Jones)--Rep. Michael Burgess (R., Texas) on Tuesday used an oil-spill hearing to raise questions about the safety of a controversial technique for accessing vast new natural-gas supplies. At a House Energy and Commerce subcommittee hearing, Burgess brought up hydraulic fracking, a procedure that involves drilling into underground rock, or shale, in order to access the gas within. The process involves pumping water and chemicals under pressure to create fissures in the shale. "It's occurring closer and closer to civilization and sometimes right on top of civilizations," Burgess said, addressing ConocoPhillips (COP) Chief Executive James Mulva. "What are you doing to create the best practices so that people on land who are nearby to the gas drilling operations can have the comfort that their safety is protected?" Mulva said that "we have a great deal of experience." He said that "our company is blessed with natural gas," which will be a "tremendous part" of the U.S. energy supply. Burgess represents an area in Texas that sits atop the Barnett Shale, one of the areas where gas companies are drilling for new gas supplies, including Fort Worth. "I'll just tell you, in my neighborhood, it may not be as secure as you think," he said. -By Siobhan Hughes; Dow Jones Newswires; 202-862-6654; [email protected] (END) Dow Jones Newswires June 15, 2010 12:35 ET (16:35 GMT)