PNNL

In high school, Brienne Seiner was passionate about her theatre activities, both behind the scenes and on stage. Today, as an advisor at Pacific Northwest National Laboratory (PNNL), Seiner channels that creativity into her many roles, which include leading the Athena project.

Launched in 2022, the Athena project focuses on increasing nuclear nonproliferation capabilities related to irradiated fuel, more commonly called spent nuclear fuel, processing. Through an unprecedented collaboration with Idaho, Savannah River, and Argonne national laboratories, the project has built a network of nearly 150 scientists.

The Athena project is funded by the National Nuclear Security Administration’s Nonproliferation Stewardship Program.

Spotlight on plutonium, spent fuel, and nonproliferation

According to the Department of Energy, the United States generates about 2,000 metric tons of irradiated nuclear fuel annually, after being used in nuclear power plant reactors. Worldwide, from 1954 to 2016, about 400,000 tons of spent fuel—which would fill 100 Olympic pools—were generated, with two-thirds in storage and one third being reprocessed or recycled.

In the shape of rods, spent fuel contains materials like uranium and plutonium (Pu), which can be repurposed into new fuel for nuclear reactors. Through defined grand challenges, the Athena project is tackling scalability, vulnerability, and maturation of processes to develop expertise on how to distinguish civilian versus military use of reprocessed materials.

With an emphasis on the nonproliferation challenges associated with spent fuel, the Athena project’s goal is centered on four research areas:

• Nuclear material processing
• Process monitoring and material characterization
• Computational modeling and simulation
• Data science.

“At PNNL, we’re fortunate to have the tools and facilities to develop and leverage all the critical skills from tracking material flow in a modern testbed to state-of-the-art analytical equipment,” said Seiner. “The Radiochemical Processing Laboratory is a living lab in action.”

Planned for completion in 2026, the new end-to-end Pu testbed will allow researchers to perform laboratory-scale investigations of irradiated fuel processing flowsheets, reestablishing a capability that has not existed at PNNL for more than 40 years. The flowsheets provide a detailed, visual documentation of the steps that gives researchers a way to improve efficiency and increase safety for the team.

The Athena team also is assessing how online monitoring can improve various flowsheets and processes that will support nonproliferation missions, which could speed up the process by weeks.

“Working together, we are world leaders in assessing and evaluating irradiated fuel processes under a nonproliferation lens,” said Seiner. “Through the success of Athena, we’ve been able to build a strong network of nearly 150 collaborative scientists across the country, who are gaining hands-on experience with new equipment and applying our skills in a nonproliferation context to help keep the world safer.”

Scientific showstopper

As an accomplished radiochemist, Seiner joined PNNL in 2010 with expertise in radiopharmaceutical development but quickly transitioned to radiochemical separations and material characterization. She has led numerous PNNL projects related to nuclear forensics, proliferation detection, and nonproliferation stewardship.

Seiner credits amazing teachers throughout her life for encouraging her passion in science. Her love of theatre grew with her need for balance, giving her an outlet and different persona from the A student in chemistry classes.

She soon learned that her stage experience gave her the comfort and confidence needed when she stood in front of a full auditorium of more than 500 people. They were waiting to hear her presentation on diagnostic nuclear medicine R&D.

“Today, hearing someone talk about deep science and helping them figure out how to tell the story—it’s something I enjoy doing,” said Seiner. “Theatre helps bring some of that together in a unique way.”

Seiner still pursues her love of the theatre. When not at work, Seiner can usually be found at the local Academy of Children’s Theatre in Richland, Washington, where she serves as a board member, watching her kids perform on stage.