Nora Khalil is leaving the Department of Energy’s National Nuclear Security Administration (NNSA) to become the lead Republican staffer on the Senate Appropriations panel that writes the agency’s annual budget bill each year,  a source familiar with the move said.

Khalil is now the agency’s associate administrator for external affairs. She will replace Adam DeMella, who is leaving Sen. Lamar Alexander’s (R-Tenn.) staff to work in Washington for the Department of Energy’s Oak Ridge National Laboratory.

Alexander chairs the Senate Appropriations energy and water development subcommittee, but the septuagenarian senator and former Tennessee governor is not standing for re-election this year. The subcommittee gets first crack each year at the spending bill that covers DoE, its semiautonomous NNSA, and the Nuclear Regulatory Commission. 

The NNSA is the semiautonomous branch of the DoE that manages U.S. nuclear weapons program. It refurbishes and maintains all active warheads and bombs, and provides fuel for the nuclear reactors that power naval warships and submarines.