SANTA FE, NEW MEXICO — The Trump administration has quietly taken steps that may inhibit independent oversight of its most high-risk nuclear facilities, including some buildings at Los Alamos National Laboratory, a Department of Energy document shows.

An order published on the department’s website in mid-May outlines new limits on the Defense Nuclear Facilities Safety Board — including preventing the board from accessing sensitive information, imposing additional legal hurdles on board staff, and mandating that Energy Department officials speak “with one voice” when communicating with the board.

The board has, by statute, operated independently and has been provided largely unfettered access to the nation’s nuclear weapons complexes in order to assess accidents or safety concerns that could pose a grave risk to workers and the public. The main exception has been access to the nuclear weapons themselves.

For many years, the board asked the Department of Energy to provide annual reviews of how well facilities handled nuclear materials vulnerable to a runaway chain reaction — and required federal officials to brief the board on the findings. It also has urged the energy […]