Lessons learned

The Lab’s Evelyn Mullen reflects on the cleanup of a contaminated Seattle building.

By Whitney Spivey | February 16, 2021

Lessons Learned Opt
February 16, 2021 Headshot of Evelyn Mullen Evelyn Mullen, chief operating officer for Global Security at Los Alamos National Laboratory. CREDIT: Los Alamos National Laboratory

Evelyn Mullen, chief operating officer for Global Security at Los Alamos National Laboratory, was among the many professionals who responded to a cesium contamination emergency at the University of Washington (UW) in Seattle in May 2019. Little did Mullen know that the incident at the University’s Research and Training Building would dominate her professional life for the next 18 months—and counting.

“As technical experts, we tend to worry about the technical problems, but working to address stakeholder needs with patience and empathy can lead to stronger partnerships.”- Evelyn Mullen

The event occurred when a contractor for the National Nuclear Security Administration’s (NNSA’s) Off-Site Source Recovery Program attempted to remove an irradiator with a cesium-137 source as part of the Cesium Irradiator Replacement Program. During the operation, the contractor inadvertently breached the sealed source, resulting in the release of radioactive cesium and the contamination of the facility. Thirteen people were impacted by the release and medically evaluated. The level of exposure to those individuals did not pose a health risk to them or to the general public.

In response to the breach, Mullen worked with others at UW, NNSA, Los Alamos, the Washington Department of Health (WDOH), and Pacific Northwest National Laboratory to understand the extent of contamination and to plan its cleanup. Their initial response stabilized the cesium source and ensured no additional contamination could occur, but remediation in the building proved to be a long-term effort. The radioactive material had to be cleaned up using elaborate decontamination methods. The multi-step process includes significant oversight, survey and sampling work, and documentation to ensure the building will be remediated to WDOH standards.

“I would not have been able to do this without Evelyn Mullen as a partner,” says Kristin Hirsch, Director of NNSA’s Office of Radiological Security. “She has been incredible to work with. Having good partners in unusual and unique situations makes everything easier and more manageable.”

Not only has Mullen applied her technical skills to the cleanup effort, but she has also interacted with local stakeholders affected by the accident. For example, staff at a nearby women’s shelter expressed concerns about whether the cesium contamination had traveled beyond the initially contaminated building. Mullen met with them virtually to let them know that continuous monitoring of the air in and around the building showed the contamination did not spread into the neighborhood.

“This incident has impacted people in ways that are well beyond the technical issues,” Mullen says. “As technical experts, we tend to worry about the technical problems, but working to address stakeholder needs with patience and empathy can lead to stronger partnerships.”

As the cleanup effort wraps up, Mullen is confident that a similar event will not occur again. In a report released in March 2020, NNSA concluded that the incident was preventable and was the result of weak and partially implemented processes.

“Everyone is responsible for safety, and a questioning attitude about safety is crucial,” Mullen says. “This incident was avoidable, which sounds trite, but it is true. We all should question our assumptions about what can go wrong in our work.”

A version of this article was published by the NNSA in December 2020.