U.S. Energy Department contractor Fluor Idaho has finished repackaging radioactive sludge waste that was ejected from four overheated drums in April 2018 at the Idaho National Laboratory.
The late-night accident spewed much of the sludge waste from the four 55-gallon drums onto the walls and ceiling of a room within a fabric filter building at the lab.
The vendor removed the last three repackaged drums from Waste Management Facility-1617 and relocated them July 30 to the Advanced Mixed Waste Treatment Project at INL.
Fluor Idaho Compliance Manager Scott Reno cited the action in an Aug. 13 report to Natalie Creed, hazardous waste bureau chief for the Idaho Department of Environmental Quality. The document is the final monthly report the company will file with the state on its response to the accident within the Radioactive Waste Management Complex’s Accelerated Retrieval Project No. 5 (ARP-5).
During processing, waste from old drums is removed and placed onto trays and checked for material that might ignite before being repackaged into new drums that will eventually travel to the Waste Isolation Pilot Plant in New Mexico.
The waste in question had already been examined for possible ignition sources, yet overheated hours after being placed into four new drums. Temperatures inside the four containers increased to about 150 degrees Celsius after depleted uranium contacted air for the first time in years. Also, material from the drums generated methane, a flammable gas.
Cleanup involved repackaging the 37 parent drums, along with waste that was on various sorting tables and the ejected material that was vacuumed up from the walls and ceilings.
Waste inside the 55-gallon drums at ARP-5 was first generated decades ago at the Rocky Flats nuclear weapons plant in Colorado.
Now that repackaging is over at ARP-5, the contractor will plan the closure of that site and concentrate on waste processing at the nearby ARP-7 facility. Continued use of ARP-5 would have required Fluor to use additional protective equipment at the site.
