A risk of combustion linked to calcium prompted suspension in November of transuranic waste shipments from the U.S. Energy Department’s Los Alamos National Laboratory to the Waste Isolation Pilot Plant further south in New Mexico, according to the Defense Nuclear Facilities Safety Board (DNFSB).
Workers discovered calcium metal in certain transuranic material that can ignite under some conditions. Risk of combustion means the shipments would not pass muster with WIPP’s waste acceptance criteria, according to a resident inspectors’ memo to DNFSB Technical Director Christopher Roscetti.
As a result, waste generation in the lab’s Plutonium Facility by managing contractor Triad National Security was temporarily curtailed, along with transuranic-waste shipments to WIPP, according to the document, which did not specify how much waste has the calcium issue.
Officials from the semiautonomous National Nuclear Security Administration, DOE’s Office of Environmental Management, WIPP, Triad, and LANL legacy cleanup contractor Newport News Nuclear BWXT Los Alamos (N3B) huddled on Nov. 12-13 to discuss the situation. They concluded that any risk of sparking ignition is small enough that waste generation and certification could resume, according to the report.
But the same officials concluded more analysis and documentation of the waste with the calcium is warranted, the memo says. In particular, they identified the need to update the waste database to include additional information on when and how this batch of waste was generated.
Los Alamos officials did not comment by press time. It is not known if shipments have resumed.
This is the second time in recent months some shipments from Los Alamos to WIPP were held up over concerns about potential combustion risks. In July, shipment of nine containers stored at Los Alamos Area G was delayed until the containers met WIPP’s waste acceptance standards.
The Energy Department tightened up its waste criteria after a February 2014 accident in which a drum from Los Alamos ruptured in the WIPP underground. That radiation release forced the disposal site out of service for nearly three years.
