The chiefs of ExxonMobil and XTO Energy today sought to defend a controversial method to extract natural gas from shale rock before skeptical House members. The process, known as hydraulic fracturing, is crucial in helping ensure the industry can become a permanent fixture in the nation's domestic energy supply, the CEOs told lawmakers at a House Energy and Commerce subcommittee hearing.

"What has enabled a new source of natural gas supply to the United States is a combination of integrated technology, but a key component is hydraulic fracturing," ExxonMobil CEO Rex Tillerson told members of the panel's Subcommittee on Energy and the Environment. "Without hydraulic fracturing, the gas locked in the shale rock would stay locked." Lawmakers, though, are still divided over whether the method poses environmental and health risks, especially to the nation's drinking water supplies.

ExxonMobil announced last month its plans to buy XTO Energy, a large independent natural gas company, for more than $40 million. If Congress moves to prohibit the use of hydraulic fracturing, Tillerson and XTO Energy CEO Bob Simpson said they could halt their plans to merge because the process is so crucial for tapping into the reserves. Energy and Environment Subcommittee Chairman Edward Markey, D-Mass., said at the hearing that the proposed merger between the oil giant and XTO "deserves our close attention."

Congress has asked the EPA to study whether the process could contaminate drinking water supplies, a concern expressed by environmentalists and some Democratic lawmakers. "The results of that will help drive policy," Markey said.

Tillerson and Simpson pointed out that hydraulic fracturing has been used for decades and maintain that it is safe. The process, also knowing as "fracking," is becoming more popular -- and thus facing more scrutiny -- because companies are finding cheaper ways to tap gas reserves from shale rock. Gas companies got a boost last week from Energy Secretary Steven Chu when he threw his support -- albeit with conditions -- behind the process.

Rep. Diana Degette, D-Colo., has introduced a bill that would require the method to be examined pursuant to the Safe Drinking Water Act. "I support the use of hydraulic fracturing, but I also support it being done in an environmentally responsible way," Degette said at the hearing.

Subscribers to National Journal can read more about hydraulic fracturing in this recent story in the magazine.

More in Energy Go to section

October 04, 2010 | Energy and Environment Bulletin

Is Unpriced Carbon The Next Subprime?

September 02, 2010 | Energy and Environment Bulletin

Dems Seek Answers On Gulf Explosion

September 01, 2010 | Energy and Environment Bulletin

BP Spent Big On Advertising After Spill

August 24, 2010 | Tech Daily Dose

Biden: Stimulus Dollars Fueling Energy and Life-Saving Technology

August 17, 2010 | Insider Interviews

Deepwater Horizon's Enduring Lessons