DEFENSE NUCLEAR FACILITIES SAFETY BOARD

February 9, 2024

TO: Katherine R. Herrera, Acting Technical Director

FROM: D. Gutowski, Resident Inspector

SUBJECT: Los Alamos Activity Report for the Week Ending February 9, 2024

Staff Activity: M. Bradisse was on site providing resident inspector support. While on site, he 

attended fact-finding meetings, toured the Weapons Engineering Tritium Facility to discuss the safety 

implications of an upcoming mission, and made several entries into the Plutonium Facility.

Plutonium Facility–Decontamination and Decommissioning (D&D): Last Wednesday, Plutonium 

Infrastructure personnel discovered several issues in a room undergoing D&D activities. This room 

contains legacy gloveboxes, which workers are cleaning and preparing for eventual removal. Workers 

discovered that while some gloveboxes in the room had the correct version of the required criticality 

safety posting, other gloveboxes had a previous version that should have been replaced. Additionally, 

the workers discovered that two drums in the room had separate issues. The first drum had a specific 

criticality safety posting that meant it was not allowed in this room. The second drum had conflicting 

labels, such that it was marked as both as “empty” and “in progress” despite containing nuclear 

material. The workers also discovered discrepancies with material inventory printouts on several 

pencil tanks, which are staged for size reduction. At the fact finding, workers stated that, during one 

work evolution, they were running low on battery power for their respiratory equipment, which caused 

them to exit rapidly and miss the conflicting labels on the second drum. Corrective actions for this 

event include developing a lessons-learned document, and evaluating techniques for displaying 

criticality safety posting techniques to ensure such postings are replaced with current versions when 

necessary and avoid inadvertently introducing disallowed items into areas. 

Last week in a different room, there was a continuous air monitor alarm in a contamination control tent 

supporting D&D work. There was no active D&D work occurring at the time; rather, personnel were 

smoke testing the tent to test for adequate ventilation flow. All personnel in the tent evacuated. 

Personnel in the laboratory room, but outside of the tent, also evacuated due to an announcement from 

the operations center. Further airflow measurements concluded that for large tents like this one, there 

can be a stagnant air layer that allows contamination to collect on elevated surfaces which can then be 

mobilized when the airflow changes. Additional filtered vents added near the top of this tent resolved 

this issue without the need for an additional air mover. This approach will be applied to future large 

tent installations. Another corrective action is to improve communications regarding the location of 

alarms to avoid unnecessary evacuations without radiological survey for personnel who are already 

one airspace away from the alarm. Unrelated to the airborne event, a management walkdown of this 

tent last week identified several housekeeping issues that were promptly resolved.

Federal Oversight: Last week, the NNSA Field Office transmitted to Triad an assessment of nuclear 

safety issues at the laboratory from the DOE Office of Enterprise Assessments (DOE-EA). The letter 

requested that Triad address the findings, deficiencies, and opportunities for improvement from the 

report. The report noted considerable improvement in issues management since the last DOE-EA

assessment in 2019. It identified two findings related to persisting weaknesses: that Triad does not 

adequately identify items that do not meet requirements or need improvement, and that Triad does not 

adequately train and qualify its workforce on identifying and resolving issues. There were also several 

deficiencies and opportunities for improvement identified for Triad and one deficiency for the NNSA 

Field Office: that the field office has not performed assessments of the contractor assurance system.