An ongoing government analysis of an important nuclear weapons laboratory's ability to withstand earthquakes may be flawed, according to a federal oversight panel.
The analysis of how the plutonium facility at Los Alamos National Laboratory would hold up in a strong earthquake "is technically inadequate" in several ways, the oversight panel wrote in a July 18 letter to the Department of Energy.
"Timely action must be taken to fully understand if additional building modifications are required," the oversight board said.
The Defense Nuclear Facilities Safety Board said in the letter that it "remains concerned by the seismic integrity of the Plutonium Facility," adding that the ongoing analysis has "profound implications for ensuring public health and safety."
The analysis in dispute is being performed by the Department of Energy's semiautonomous National Nuclear Security Administration (NNSA) and by the contractors that operate the New Mexico laboratory.
Asked for comment, NNSA spokesman Joshua McConaha said his agency is working on a response to the oversight panel.
"Regardless of any future improvements, the risk to the public from operations at [the Los Alamos plutonium facility] remains very small," he said, adding that "the facility is operating well within the safety objectives established by [Department of Energy] safety policy, and public safety is adequately protected."
The oversight panel's criticism comes one month after the panel issued a report that found that Los Alamos National Laboratory had underestimated the amount of radiation that could leak from the plutonium facility as a result of an earthquake. As the Project On Government Oversight reported, the panel concluded that the radiation could be more than four times as intense as the laboratory had estimated.
"The latest safety concerns about Los Alamos drive home the need for independent oversight of the nation's nuclear weapons labs," said Danielle Brian, executive director of the Project On Government Oversight. "The Defense Nuclear Facilities Safety Board and other government investigators play a key role in holding the labs accountable and keeping the public safe."
The plutonium facility was designed and built in the 1970s and lacks the earthquake resistance required by modern building codes, the oversight panel said in its July 18 letter.
As a result, in the event of a strong earthquake, the facility is "susceptible to catastrophic structural failure," according to the letter.
In 2007, the contractor that runs Los Alamos found that an earthquake near the facility could cause ground motions up to five times greater than the facility was designed to withstand, the letter said.
Los Alamos, which is located 35 miles outside of Santa Fe, was last shaken by an earthquake in October 2011, according to the U.S. Geological Survey.
The oversight panel demanded that the Department of Energy write a report within 30 days explaining how it is assessing the facility's vulnerability to a strong quake.