Los Alamos National Laboratory’s Plutonium Facility (PF-4) is continuing to draw concern from the Defense Nuclear Facilities Safety Board. In its second PF-4-related
letter to the Department of Energy in the span of a month, the DNFSB said it was concerned about the ability of the facility to withstand an earthquake and that it was troubled by the National Nuclear Security Administration’s approach to assessing the facility’s seismic behavior. “The Board believes that NNSA’s current approach for assessing the Plutonium Facility’s seismic behavior is not adequately defined, and is technically inadequate in several aspects,” DNFSB Chairman Peter Winokur said in letter to Deputy Energy Secretary Dan Poneman. “Timely action must be taken to fully understand if additional building modifications are required to eliminate or mitigate any remaining structural vulnerabilities in the design.”
At issue, according to Winokur, is the NNSA’s approach to defining how the facility would react during an earthquake. The facility, built in the 1970s, was not designed to withstand new estimates about the potential for massive earthquakes in Northern New Mexico that could result in ground motions five times stronger than previous estimates. The NNSA has poured millions into upgrading the facility, but last month the Board suggested that potential exposures from an earth-quake induced fire still were nearly four times DOE guidelines. “NNSA and its contractor are currently performing a static nonlinear analysis intended to definitively characterize the Plutonium Facility’s structural response to large earthquake ground motions,” Winokur wrote. “The Board is concerned that the ongoing static nonlinear analysis is proceeding without adequate definition and technical justification.” Winokur said the Board wanted a briefing within 30 days on its concerns. In a statement, NNSA Assistant Deputy Administrator for Nuclear Safety, Nuclear Operations, and Governance Reform Jim McConnell said the agency would take into account the DNFSB’s concerns as it makes improvements at PF-4. “The NNSA considers the safety of the public our highest priority,” McConnell said. “We are working with Los Alamos National Laboratory to respond to the DNFSB. If necessary or prudent, we will take appropriate actions to further improve the safety basis that documents the hazards and specifies the controls to ensure safety at the Plutonium Facility, PF-4, even as ongoing physical improvements continue to improve the overall safety posture of the facility. Regardless of any future improvements, the risk to the public from operations at PF-4 remains very small; the facility is operating well within the safety objectives established by DOE safety policy, and public safety is adequately protected.”
