DEFENSE NUCLEAR FACILITIES SAFETY BOARD

February 23, 2024

TO: Katherine R. Herrera, Acting Technical Director

FROM: B. Caleca, P. Fox, N. Huntington, and P. Meyer, Resident Inspectors

SUBJECT: Hanford Activity Report for the Week Ending February 23, 2024

High Level Waste (HLW) Facility: DOE briefed contractors on the results of their Baseline 

Design Review of the HLW facility, given the direct feed HLW approach. The team elected to 

review major facility systems, considering their interfaces with other systems in determining 

design maturity, design improvement opportunities, and concerns with the current approach. 

The team’s results are largely in line with the contractor’s estimates of design maturity, noting 

areas to reduce complexity and improve maintenance and operability. 

West Area Risk Management (WARM): WRPS held a kickoff meeting for the WARM Safety 

Design Integration Team (SDIT). The SDIT received presentations on the status of the Safety 

Design Strategy and conceptual design. WARM will utilize the SY Tank Farm for feed receipt 

and preparation. Remediation of Tank SY-103 (see 2/16/2024 report) and installation of needed 

equipment in the SY Farm will be made under changes to the existing Tank Farms Documented 

Safety Analysis (DSA). New construction, including the ion exchange treatment system and a 

low activity waste storage capability, will be a major modification to the tank farm DSA.

Tank Farms: The resident inspectors met with WRPS pipe integrity engineers to discuss 

ongoing efforts to understand the extent and effect of retained water in transfer line encasements

and primaries (see 5/27/2022 report). The inspections determined that there is localized pitting 

corrosion on the interior surface of some transfer lines. The engineers also noted that observed 

conditions challenge the free draining assumption that underlies previous pipe integrity 

evaluations. They also noted that conditions varied between tank farms, indicating that a single 

approach for managing transfer lines may not be appropriate. Based on their evaluation, they 

expect that the pipe integrity program will be modified to require more frequent pneumatic 

pressure integrity tests, periodic borescope inspections within the encasements, adjustments to 

flushing practices to mitigate corrosion mechanisms, and ultrasonic measurements to confirm 

mitigation effectiveness. 

222-S Laboratory: HLMI held an event investigation meeting to discuss the Richland Bomb 

Squad’s removal of two milliliters of crotonaldehyde from the facility after it was determined to 

have explosive properties. The chemical, which was being prepared for disposal, had an opaque

outer package and the conditions inside were unknown prior to opening it. When opened, the 

physical properties of the crotonaldehyde were different than expected. The work was stopped, 

and the room was restricted. It was determined that peroxidation may have occurred, which 

prompted bringing in the bomb squad to handle the material. Further, restrictions of adjacent 

rooms were established. The facility was evacuated prior to the bomb squad removing the 

chemical. At the meeting, it was found that the manufacturer’s storage requirements were not 

maintained after the chemical was dispositioned as waste and it was not known if the storage 

requirements were met prior to receipt. In addition, the process for inspecting chemicals based on 

quantity and not requiring periodic inspection of waste was questioned. HLMI is evaluating 

their processes and will determine if a potential inadequacy in the safety analysis exists.