LANL gets backing on safety violation

SANTA FE — The National Nuclear Security Administration is backing up Los Alamos National Laboratory in its statement this week that a recent safety violation did not pose a risk of an accidental nuclear fission chain reaction.

“At no time was there any risk of an inadvertent criticality,” said a statement from an NNSA spokesman. “There was also no risk of injury or exposure to the workforce or public. The laboratory has since taken steps to help prevent a similar event in the future, and the qualifications of the workers involved were suspended pending rigorous retraining.”

A recent report by the Defense Nuclear Safety Facilities Board said that in August, a LANL crew that cast a shell for a plutonium “pit” — the trigger for a nuclear weapon — moved it “into a location that already contained plutonium metal,” exceeding nuclear material limits. The board described the incident as a “criticality safety event.”

Too much plutonium in close quarters can cause a criticality reaction, producing a potentially fatal blast of radiation. In this case, the plutonium limit violation was discovered five days later when the pit shell was moved again.

NNSA said “there are multiple layers of defense to prevent accidents involving these materials.”

Greg Mello, of Albuquerquebased Los Alamos Study Group, said that if there was no problem with LANL’s plutonium limit violation, “Why did NNSA and LANL have the rules in question, the rules that were violated? Does NNSA encourage its contractors to violate its rules? To violate posted material limits?”