Mr. Monninger is the Regional Administrator of the NRC’s Region IV organization located in Arlington, Texas. He joined the NRC in 1989 as a Reactor Engineer in the Office of Nuclear Reactor Regulation (NRR). From 1989 to 2001, he held a number of progressively more responsible positions, including Reactor Systems Engineer in the Plant Systems Branch, NRR; Reactor Systems Engineer in the Containment Systems and Severe Accident Branch, NRR; Technical Assistant to the Associate Director for Inspection and Programs, NRR; and Technical Assistant to the Chairman. In 2001, he was selected as the Chief of the Licensing Section in the Spent Fuel Project Office, Office of Nuclear Material Safety and Safeguards. Since joining the Senior Executive Service (SES) in 2006, Mr. Monninger served in several senior management positions, including Deputy Director, Division of Risk Assessment and Special Projects, Office of Nuclear Regulatory Research; Deputy Director, Division of Safety Systems and Risk Assessment, Office of New Reactors (NRO); Deputy Chief of Staff, Office of the Chairman; Associate Director for the Japan Lessons-Learned Project Directorate; Deputy Director, Division of Operating Reactor Licensing, NRR; Director, Division of Safety Systems and Risk Assessment, NRO; Director, Division of Advanced Reactors, NRO; and Director, Division of Advanced Reactors and Non-Power Production and Utilization Facilities, NRR. In September 2020, he assumed the position of Deputy Regional Administrator, Region IV.

Mr. Monninger received a Bachelor of Science Degree in Nuclear Engineering from the University of Maryland. He is a 2006 graduate of the NRC's SES Candidate Development Program and a recipient of the NRC's Meritorious Service Award.