The National Nuclear Security Administration’s Office of Enterprise Assessments is investigating an incident at the Y-12 National Security Complex in which a machine used to shape uranium was dismantled without proper criticality controls in place.
In a letter dated Aug. 3, Anthony Pierpoint, director of the NNSA’s office of enforcement, notified Consolidated Nuclear Security’s (CNS) Chief Executive, Richard Tighe, of its intent to investigate the incident in Building 9215, which occurred April 14 and was reported in May.
CNS manages both Y-12 in Oak Ridge, Tenn., and the Pantex Plant in Texas, on behalf of the NNSA. Among other missions, Y-12 assembles the secondary stages of nuclear weapons and provides highly enriched uranium used to build reactors for the Navy’s nuclear-powered aircraft carriers and submarines under an agreement with NNSA’s Naval Reactors Office.
CNS reported the potential noncompliances associated with this event to the Department of Energy’s (DOE) Noncompliance Tracking System on May 25, Pierpoint’s letter said.
A CNS spokesperson told Exchange Monitor that the building 9215 “issue was discovered when demolishing a legacy machine.”
“The event did not have the potential to result in a criticality accident because the majority of the material was fixed in small-diameter piping,” the CNS spokesperson said. “We are aware of and will cooperate with the Office of Enforcement’s investigation. The safety of our employees, the community, and the environment is our top priority. We have investigated the causes of the event and are implementing corrective actions.”
Y-12 in 2022, for a fourth year in a row, saw no employees exposed to a dose of radiation of more than 350 millirem, CNS recently announced. People receive an average annual dose from natural and manmade sources of roughly 620 mrem, or 310 mrem from radon in the air, cosmic rays, and earth materials and 310 mrem from medical, commercial, and industrial sources each year, Y-12 said on its blog.
Y‑12 Deputy Site Manager Jan West, who served as senior director of Safety and Industrial Hygiene, said “these rates don’t happen by accident.”