Committee member Rep. Rush Holt, D-N.J., listens to testimony before a Subcommittee on Energy and Mineral Resources on proposed nationwide drilling rules on hydraulic fracturing at the Capitol in Denver on Wednesday, May 2, 2012. (AP Photo/Ed Andrieski)

Photo by: Ed Andrieski

Committee member Rep. Rush Holt, D-N.J., listens to testimony before a Subcommittee on Energy and Mineral Resources on proposed nationwide drilling rules on hydraulic fracturing at the Capitol in Denver on Wednesday, May 2, 2012. (AP Photo/Ed Andrieski)