The management and operations contractor at the Savannah River Site (SRS) recently completed a three-phase process optimisation outage to create efficiencies to help the US Department of Energy (DOE) expedite plutonium down-blending and removal from South Carolina.
The efficiencies introduced in the outage at the K Area Interim Surveillance (KIS) glovebox completed by Savannah River Nuclear Solutions (SRNS) are projected to result in significant cost avoidances over the next five years.
These improvements will further US non-proliferation objectives and work toward strengthening the National Nuclear Security Administration's (NNSA’s) relationship with South Carolina, said Nicole Nelson-Jean, DOE Environmental Management associate principal deputy assistant secretary for field operations, who previously served as NNSA manager of the Savannah River Field Office.
“Combining current and future planned missions at SRS will result in the need for faster plutonium processing,” SRNS K Area Facility Manager Steve Wilkerson said. “All plutonium down-blending is done in the KIS glovebox, so we looked for ways to make the process easier and faster while still maintaining safety.”
The KIS glovebox is a stainless-steel enclosure that is 15 feet long and three feet wide with safety glass panels. It has fitted glove-port openings to allow radioactive materials handling, and isolates workers from associated hazards. The glovebox was put into operation in 2007 and needed to be retrofitted to align with the ramping up of the down-blending mission.
The project scope required open glovebox maintenance, which involved removing one of the safety glass panels and attaching a new wing cabinet. This specialised cabinet installed on the side of the glovebox allows for safer and more efficient introduction of nuclear material and processing supplies.
This work is high hazard and required a custom containment structure to be built around the open glovebox area. Operators were required to wear air-fed plastic suits, and temporary glovebox ventilation was installed for contamination control.
A wing cabinet installation was part of the second phase of the K Area Interim Surveillance glovebox process optimisation scope.
Some of the improvements implemented in the project included installing new material entry and removal devices for the glovebox; acquiring new tools that allow for tight bag closure, minimizing waste generation; designing and fabricating special carts to move the down-blending containers through the glovebox; and relocating equipment inside the glovebox to improve efficiency of the down-blending process flow.
Staff for down-blending moved to two-shift operations before the outage, with the plan of moving to four-shift operations during the next fiscal year to increase processing rates for expedited removal of plutonium from the state. Down-blending operations in the optimised glovebox resumed in July 2020.
Plutonium down-blending is the process of mixing plutonium oxide with a multicomponent adulterant to enable DOE to meet requirements for shipping plutonium to an out-of-state repository for disposition. “NNSA thanks the SRNS project team and the facility support personnel for their hard work in helping us achieve this important non-proliferation mission,” said Virginia Kay, director of the NNSA Office of Material Disposition. “SRS remains committed to removing plutonium from the state of South Carolina as safely and quickly as possible.”