The DOE Hanford Site did not meet a technical safety requirement regarding the fissile mass of a waste box, according to a Feb. 28 report by the Defense Nuclear Facilities Safety Board.
Personnel at the site discovered the waste box with a fissile mass value exceeding the container limit in an outside storage area, according to a Nov. 11 report by the federal nuclear safety watchdog.
Due to the review that succeeded this event, it was determined that the fissile material in the box is more concentrated in some areas than what was put in the Critical Safety Evaluation Report (CSER).
The DNFSB determined that the CSER is now “inapplicable,” and that a critical safety requirement was not met. A new CSER is required to address “mass limits and controls for this container,” the report said.