The Department of Energy has not fully analyzed the risk of certain types of accidents at the Idaho National Laboratory’s Integrated Waste Treatment Unit (IWTU), according to the Defense Nuclear Facilities Safety Board (DNFSB).
In a March 27 letter to DOE, the DNFSB cited weaknesses in the safety planning conducted for the IWTU: These types of events could “require identification of safety-significant controls for protection of workers.”
The board finished reviewing the safety basis for IWTU in October 2017. Several risks identified during the process are characterized by DOE as “standard industrial hazards” and rely upon “site-wide safety management programs.” As a result, DNFSB said in the letter, IWTU’s safety basis doesn’t properly analyze some dangers.
Such events, such as carbon dust fires in a silo and oxygen displacement in process areas, could require additional controls, the DNFSB said.
The board also said the facility’s fire hazard analysis is too reliant on site-wide safety management programs to screen out hazards, and that doesn’t live up to DOE requirements. For example, a “carbon dust fire could spread to the adjacent mechanical area, potentially damaging the safety-significant components in that space,” the letter says.
At IWTU, the Energy Department has implemented some safety programs and controls intended to address potential hazards. The DNFSB said these efforts could be beefed up through better documentation.
“The Department has received the DNFSB letter,” a DOE spokesperson said by email last week. “It appreciates receiving the board’s perspective and will evaluate the information provided as the Department continues preparations at IWTU.” The board’s letter itself did not request a written reply from DOE.
The IWTU was completed in 2012 to treat about 900,000 gallons of liquid radioactive waste are stored in underground tanks at Idaho, but it did not operate as expected. The Energy Department has spent years trying to fix the operational issues and hopes to start treating radioactive waste by the end of this year.
The Energy Department has to date been fined $3.6 million by the state of Idaho for failure to successfully start operating the facility, according to Natalie Creed, hazardous waste unit manager for the Idaho Department of Environmental Quality.
The DNFSB is an independent board within the executive branch, which gives recommendations and advice to the energy secretary about health and safety issues at DOE nuclear defense sites.
