IWTU operators prepare to introduce radiological sodium-bearing liquid waste into the facility Tuesday. (Photo: DOE)

More than a decade after construction was declared completed, Idaho’s long-delayed Integrated Waste Treatment Unit (IWTU) has begun radiological operations, the Department of Energy’s Office of Environmental Management (EM) announced.

On Tuesday, crews at the Idaho National Laboratory Site began sending radioactive sodium-bearing liquid waste from nearby underground tanks to the IWTU for treatment. The 900,000 gallons of waste was generated during decontamination activities following spent nuclear fuel reprocessing that ended in 1992.

The IWTU uses steam reforming fluidized-bed reactor technology to convert liquid waste to a granular solid resembling coarse sand more suitable for long-term disposal.