IDAHO FALLS, Idaho – Construction of the final Accelerated Retrieval Project (ARP) structure at EM’s Idaho Site is complete. But before crews begin exhuming the final 0.69 acres of buried transuranic (TRU) waste within its walls, the facility will be used to treat a challenging waste form.
“Roaster oxides,” depleted uranium material generated at the former Rocky Flats Plant near Denver, were shipped to the Idaho Site for disposal along with plutonium, americium, and other waste. Prior to its arrival, the uranium material was roasted to force the reactive metal to oxidize and render it safer for transport and ultimately disposal.
During waste exhumation at ARP, roaster oxides occasionally spark when exposed to atmospheric conditions.
“We’ve encountered roaster oxides many times since we began targeted buried waste remediation in early 2005,” said Jason Chapple, ARP operations director with EM cleanup contractor Fluor-Idaho. “We’ve employed many safety measures to deal with roaster oxides and our workforce has a history of safely handling this material.”
The nearby Advanced Mixed Waste Treatment Project (AMWTP) is used to retrieve, characterize, treat, and ship above-ground waste that came from Rocky Flats years ago. Inside that facility are several hundred containers of roaster oxides that must be conditioned and repackaged for offsite disposition.
With construction of ARP IX complete, and exhumation of the 0.69 acres of buried TRU waste not scheduled to begin until later this year, ARP IX is a suitable place to repackage AMWTP’s roaster oxides.
A specially designed excavator will empty each container of roaster oxides onto a table, rake through the material, condition any reactive material to a non-reactive state, and load waste trays for processing through a drum packaging station. Each tray of waste will then be packaged into a new 55-gallon drum and sent offsite for disposal.
Roaster oxide treatment will begin in early March and continue for several months. After that mission is complete, workers will begin exhuming TRU and hazardous waste to remove it from a combined area of 5.69 acres of the site's 97-acre Subsurface Disposal Area.