Department of Energy (DOE) Environmental Management (EM) Workers at the Savannah River Site have completed deactivation of a former material storage building containing residual hold-up of plutonium (Pu)-238 oxide, once used to power deep space missions. The two-story, blast-resistant, windowless, reinforced concrete building, known as Building 235-F, has been inactive for more than 25 years. One section of Building 235-F, known as the Plutonium Fuel Form (PuFF) Facility was used to make fuel spheres and pellets out of Pu-238 to provide heat to electrically power longterm, deep-space missions, such as Galileo, Ulysses and Cassini.

“Deactivation of 235-F began in 2019,” said Building 235-F Project Manager Jeff Hasty. “Deactivation will prepare the facility for Long Term Safe Storage, which is an end state relatively free of non-radiological hazards, with acceptable radiological risks, and minimal continuing surveillance and maintenance.” Hasty also explained that the deactivation will also prepare the facility for eventual decommissioning.

“The deactivation project included the reconfiguration/shutdown of the ventilation system; isolation of all utilities (water, steam, power, etc.); removing contamination or using a permanent coating, called a fixative, that prevents contamination from spreading outside of the process enclosures and removing non-radiological hazardous material (i.e., lead, oils, process water, etc.) This shutdown/isolation will greatly reduce the cost for surveillance and maintenance (S&M) of Building 235-F during Safe Storage.” The DOE and SRNS have worked with the South Carolina Department of Environmental Control (SCDHEC and the Environmental Protection Agency (EPA) to finalize plans for the decommissioning of Building 235-F. The end state determination is complete and includes approval from both US EPA and SCDHEC. Based on the risk to the workers, protection of human health, environmental impacts, and cost, it was decided that grouting the process areas and emplacement of a durable sloped roof was the recommended disposition path. Decommissioning will be a multi-year project that is planned to commence in fiscal year 2023.

The decommissioning of 235-F will be similar to decommissioning of the former reactor facilities in P and R areas at SRS. “We are pleased to see another SRS facility nearing decommissioning,” said DOE Nuclear Materials Program Manager Bert Crapse. “This helps further the Department of Energy’s mission of footprint reduction at SRS and reduces risks to workers, the public and the environment.”