Another day, another security lapse at one of the Department of Energy’s nuclear weapons labs.

The Government Accountability Office is reporting yet again that there are security lapses in the complex, this time at Lawrence Livermore National Laboratory in California, near San Francisco.

LLNL is one of three DOE national labs that designs, handles and stores nuclear weapons. It also maintains stores of plutonium and enriched uranium.

Investigators found 13 specific deficiencies in the security force employed to counteract a terrorist attack. Among other problems, the security force didn’t put on chemical masks fast enough, and a tank-like vehicle with a mounted machine gun failed to “competently support” the mission. Investigators also found seven instances of lapses in physical security, i.e., issues with alarms and keys and vaults.

Yet the lab was assessed with a security performance grade of 100% by the on-site federal oversight office of the National Nuclear Security Agency, the quasi-independent, but much-maligned organization within DOE that’s supposed to be responsible for the weapons labs.