The National Nuclear Security Administration must address safety concerns involving the seismic safety controls at the lab that does subcritical experiments to account earthquake- and other related-risks, according to a safety report.
According to a review posted online, the Defense Nuclear Facilities Safety Board (DNFSB) evaluated the safety designs at the Principal Underground Laboratory for Subcritical Experimentation (PULSE) at the Nevada National Security Site. The board found NNSA had not adequately characterized seismic faults, meaning the safety controls might not account for earthquakes accurately or perform their intended safety function.
The DNFSB also identified an “inadequate” control set for moving subcritical experiments, “inadequate” exits for workers at the facility, and “unevaluated” effects of changing performance criterion for the vessel confinement system.
The board requested that NNSA write a report within 120 days that answers questions such as which actions it took to characterize seismic faults to ensure the controls perform their safety functions, as well as to provide adequate exits for workers to evacuate quickly.
The Nevada National Security Site conducts subcritical experiments at PULSE with aims to support stewarding the stockpile at NNSA without testing any nuclear weapons.