President Obama on Tuesday nominated a former Energy Department official in the George W. Bush administration as a commissioner for the nation's nuclear regulator.

Jessie Roberson would fill out the five-member Nuclear Regulatory Commission, which has seen significant turnover in the past year. She has previous federal experience, as she served as the Energy Department's assistant secretary for environmental management, which oversees nuclear waste cleanup, from 2001 through 2004.

If confirmed, Roberson would be the third new commissioner to join the regulatory agency since September 2014. Democrats Allison Macfarlane, who was chairwoman of the commission, and William Magwood, both resigned last year while George Apostolakis' term expired.

Roberson since 2010 has been vice chairwoman and a member of the Defense Nuclear Facilities Safety Board. She also has served as a consultant and worked at a few electric utilities, including running the nuclear regulatory program at Exelon Corp., which operates more nuclear power than any other electric utility in the United States.