Characterization of low level mixed waste at Los Alamos National Laboratory

The characterization program was conducted to maintain regulatory compliance and support ongoing waste treatment and disposal activities. The characterization team conducted a characterization review of wastes stored at the Laboratory that contain both a low-level radioactive and a hazardous component. The team addressed only those wastes generated before January 1993. The wastes reviewed, referred to as legacy wastes, had been generated before the implementation of comprehensive waste acceptance documentation procedures. The review was performed to verify existing RCRA code assignments and was required as part of the Federal Facility Compliance Agreement (FFCA). The review entailed identifying all legacy LLMW items in storage, collecting existing documentation, contacting and interviewing generators, and reviewing code assignments based upon information from knowledge of process (KOP) as allowed by RCRA. The team identified 7,546 legacy waste items in the current inventory, and determined that 4,200 required further RCRA characterization and documentation. KOP characterization was successful for accurately assigning RCRA codes for all but 117 of the 4,200 items within the scope of work. As a result of KOP interviews, 714 waste items were determined to be non-hazardous, while 276 were determined to be non-radioactive. Other wastes were stored as suspect radioactive. Many of the suspect radioactive wastes were certified by the generators as non-radioactive and will eventually be removed