National Nuclear Security Administrator Frank Klotz told sister publication Weapons Complex Morning Briefing on Tuesday he will retire from the semi-autonomous Department of Energy nuclear-weapon agency on Jan. 19.

If he leaves the agency as planned in two weeks, the retired Air Force lieutenant general will have helmed the NNSA for three years, nine months, and 12 days, including one year in the Trump administration.

National Nuclear Security Administrator Frank Klotz
National Nuclear Security Administrator Frank Klotz

Klotz confirmed his departure date in a brief interview on Capitol Hill, after he testified in an hours-long hearing about modernizing the agency he soon will leave. The NNSA manages the Department of Energy’s (DoE) active nuclear weapons programs, which cost around $13 billion a year.

In December, Trump nominated former DoE and National Security Council staffer Lisa Gordon-Hagerty to replace Klotz as NNSA administrator. She still awaits a confirmation hearing in the Senate Armed Services Committee and a confirmation vote on the Senate floor.

If Klotz sticks to his departure schedule, he will be the second-longest-serving NNSA administrator since Congress created the quasi-independent weapons-agency in 2000.Thomas D’Agostino, Klotz’s Bush-appointed predecessor, is the longest-serving NNSA administrator to date, serving nearly five-and-a-half years in the top spot, mostly during the Barack Obama administration. Obama nominated Klotz to replace D’Agostino on Jan. 6, 2014, and the Senate confirmed him on April 8 of that year.

With the No. 2 NNSA position vacant, it was not immediately clear who will lead the agency on an interim basis after Klotz leaves — his deputy, Madelyn Creedon, resigned after Trump took office in January 2017. If the responsibility falls to the third-highest-ranking NNSA official, then William White, Klotz’s chief of staff and associate principal deputy administrator, would take the reins temporarily.