[en] This document provides historical evaluations of the radioactive and mixed waste stored in the Hanford site underground double-shell tanks. A Historical Tank Content Estimate has been developed by reviewing the process histories, waste transfer data, and available physical and chemical characterization data from various Department of Energy and Department of Defense contractors. The historical data will supplement information that is currently being gathered from core sampling. Historical waste transfer and level data, tank physical information, temperature data, and sampling data have been compiled for this report and supporting documents