Characterization Plan for Establishing a PCB Baseline Inventory in Hanford Waste Tanks

Abstract

In May 2000, the U.S. Department of Energy, Office of River Protection (DOE-ORP) and the U.S. Environmental Protection Agency (EPA) conducted meetings to discuss management of polychlorinated biphenyls (PCBs) in the Hanford tank waste. It was decided that the radioactive waste currently stored in the doubleshell tanks (DSTs) will be managed to comply with the Toxic Substance Control Act (TSCA) (40 CFR 761). As a result, DOE-ORP directed the River Protection Project tank farm contractor to prepare plans for managing the PCB inventory in the DSTs. One component of the PCB management plans is this characterization plan. At this time, available PCB data for Hanford tank waste is limited to thirteen DSTs and one single-shell tank (SST). Only concentration data for some individual Aroclors (i.e., commercial PCB mixtures) are available for these tanks. Total PCB data is needed to establish a baseline inventory of PCBs in the DSTs. Appropriate transfer controls for the tanks will be developed based on the baseline inventory. The controls will be used to ensure PCB levels in the DSTs will not exceed anticipated waste feed acceptance criteria of the Waste Treatment Facility (WTF). Approximately ninety percent of the waste to be received at the DSTs in the future will come from the SSTs (Strode and Boyles 1999). Single-shell tank waste will be retrieved into the DSTs prior to treatment for disposal. Liquids from the SSTs currently are being transferred to the DSTs as part of the interim stabilization effort. In addition, waste sample materials taken from the SSTs have been and will continue to be sent to the DSTs after analysis by the site laboratories. Thus, to properly manage the PCB inventory in the DSTs, baseline characterization data of SST waste is also needed.