A pair of new federal reports raise questions about the "unknown" risks of the hydraulic fracturing techniques used in natural gas development, and whether national regulators should be more involved in the oversight process.
While the two Government Accountability Office reports do not make any policy recommendations, researchers say the prior studies they reviewed do not adequately weigh potential long-term effects from hydraulic fracturing.
Officials interviewed at the U.S. Environmental Protection Agency told researchers that they face oversight challenges related to limited information on drilling activity and the industry's rapid development. The majority of oil and gas drilling oversight is done by state regulators.
The reports also cite Energy Information Administration's increasing estimates for the amount of oil and gas believed to be contained within U.S. shale formations.
Natural gas imports decreased by 5 percentage points between 2007 and 2010, according to the reports. The U.S. will be a net exporter of natural gas by 2022.