Reduction-Oxidation Complex, Plutonium Concentration Facility, 200 West Area, Richland, Benton County, WA

Significance: Building 233-S, the Plutonium Concentration Facility, was constructed as part of the Reduction-Oxidation (REDOX) Canyon and Service Facility's Phase II Capacity Increase on the Hanford Site. While 233-S is not individually eligible for listing in the National Register of Historic Places, it does appear to merit consideration as a contributing element to a potential historic district centered on the adjacent REDOX canyon building (202-S) as both facilities were closely connected. Located adjacent to the north wall of 202-S, the 233-S building provided final purification and concentration of plutonium solutions using an ion-exchange process. In 1963 a chemical reaction in the exchange column in 233-S resulted in a fire that spread plutonium contamination throughout most of the building. After clean-up the facility was used for concentration of plutonium and neptuniun nitrate solutions from the REDOX plant until 1967, when both 233-S and REDOX were sealed off and retired from service.
Unprocessed Field note material exists for this structure: N463
Survey number: HAER WA-129-A