A longtime Amentum executive, Jim Blankenhorn has been selected as the new president and chief executive officer of United Cleanup Oak Ridge (UCOR), the environmental prime at the Department of Energy’s Oak Ridge Site in Tennessee.
Blankenhorn assumes the top job at UCOR effective April 1, 2026. UCOR said in a Dec. 16 press release that Blankenhorn will replace Ken Rueter, who has announced plans to retire effective March 30, 2026.
Blankenhorn, who has spent 38 years in the nuclear industry, is currently senior vice president of Amentum’s Energy & Environment North America branch. He has ample experience working around the DOE’s nuclear weapons complex and its Office of Environmental Management.
In past work, Blankenhorn was recovery manager, deputy project manager and chief operating officer for the Amentum-led Nuclear Waste Partnership at the Waste Isolation Pilot Plant (WIPP) in Carlsbad, N.M. According to his bio, Blankenhorn helped restart WIPP’s transuranic waste disposal program after a 2014 underground radiation leak damaged the mine and kept the facility offline for about three years.
The incoming UCOR boss Blankenhorn has also worked at the West Valley Demonstration Project in New York, the Los Alamos National Laboratory in New Mexico and the Savannah River Site in South Carolina.
Blankenhorn has also served as a brigadier general in the U.S. Army Reserve.
UCOR currently consists of Amentum, Honeywell and several small business teaming partners.