An obscure facility at Los Alamos National Laboratory for nine years provided vital scientific data about a critical gas used in America’s arsenal of nuclear weapons, until it was shuttered four years ago due to a raft of safety problems that have stubbornly persisted. The Energy Department, which oversees and finances the lab’s work, has poured tens of millions of dollars into fixing the problems, but so far, the expenditures haven’t borne much fruit. The facility – known as the Weapons Engineering Tritium Facility – is “vital” to the lab’s national security mission, but it remains closed, the department’s inspector general said in a report released July 20. In fact, Los Alamos managers have been unable – after seven years of effort – even to prepare a sound analysis of the site’s safety hazards and the steps being taken to ensure that the radioactive gas at issue does not leak or explode and harm either workers or those living nearby, according to the DOE report. DOE Inspector General Gregory H. Friedman said in the report that poor hazard analysis has been a recurrent problem at the lab, and said weaknesses in other projects have remained unfixed from one annual evaluation to the next.