AIKEN, S.C. – The management and operations contractor at the Savannah River Site (SRS) recently completed a three-phase process optimization outage to create efficiencies to help DOE expedite plutonium downblending 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 important improvements will further our nation’s nonproliferation objectives and work toward strengthening NNSA’s relationship with the great state of South Carolina,” said Nicole Nelson-Jean, EM associate principal deputy assistant secretary for field operations, who previously served as manager of the National Nuclear Security Administration's (NNSA) 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 downblending 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, so it needed to be retrofitted to align with the ramping up of the downblending mission.
The project scope required open glovebox maintenance, which involved removing one of the safety glass panels and attaching a new wing cabinet. This specialized 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.
The three phases of the outage included:
- All work required for construction, such as electrical, that does not require specialized equipment or present high radiological concerns.
- Glovebox panel removal and installation of the wing cabinet. Old equipment and waste were removed from the open glovebox panel and new equipment was put inside.
- Tie-in of the rest of the equipment from Phase 1 that could not be completely installed until Phase 2 was completed. At the start of Phase 3, the containment structure was removed, and radiological conditions were returned to a steady state.
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 downblending containers through the glovebox; and relocating equipment inside the glovebox to improve efficiency of the downblending process flow.
Staff for downblending 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. Downblending operations in the optimized glovebox resumed in July 2020.
“I am proud of the team and their commitment to safety during this project,” Wilkerson said. “There was a lot of prep work done before we began the optimization outage. To meet an aggressive schedule for process optimization, our team built and practiced on a mock-up glovebox before beginning any higher risk radiological scope. We did a lot of advanced planning and communicating with the customer to complete this high hazard work in a small space safely. This is the first time open glovebox maintenance has been performed on the KIS glovebox since it was installed in 2007.”
Plutonium downblending 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 nonproliferation 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.”