A statement from Nevada Gov. Steve Sisolak (D) on Wednesday said the department sent a total of 32 shipments to the Nevada National Security Site between 2013 and 2018 that were supposed to be low-level radioactive waste from a facility in Tennessee. (The DOE told the Las Vegas Review-Journal later on Wednesday that there were actually nine shipments that had 32 containers.)
But DOE Deputy Secretary Daniel Brouillette told Sisolak on July 3 that some of those shipments may have included “reactive” material, which can release large amounts of thermodynamic energy.
Sisolak’s office said DOE officials have not confirmed that the shipments definitely contained reactive materials, which he said “would trigger additional safety concerns,” but the department did confirm Wednesday to the Review-Journal that the shipments were not in compliance with the security site’s waste acceptance criteria.
The security site has been a place to permanently dispose of what the DOE categorizes as low-level radioactive waste, which can include materials like rags, construction debris and other equipment exposed to radioactive material. The site also takes in some forms of “mixed low-level waste,” which can contain some hazardous waste such as garbage and sludge. The governor’s office said mixed low-level waste is more strictly regulated and requires treatment prior to disposal and a more protective disposal method than low-level waste.
The shipments in question were not properly labeled to indicate which materials were low-level waste and which were more dangerous.
Federal officials, including from the National Nuclear Security Administration, gave an in-person briefing to Sisolak on Tuesday regarding the department’s findings and proposed response. During the briefing, the governor referred to an incident last year in which the DOE shipped half a metric ton of weapons-grade plutonium to the same security site and didn’t give notice until months later.