This report is the official inventory for radioactive waste stored in underground tanks in the 200 Areas at the Hanford Site. Data that depict the status of stored radioactive waste and tank vessel integrity are contained within the report. This report provides data on each of the existing 177 large underground waste storage tanks and 63 smaller miscellaneous underground storage tanks and special surveillance facilities and supplemental information regarding tank surveillance anomalies and ongoing investigations. This report is intended to meet the requirement of U S Department of Energy-Richland Operations Office Order 435 I (DOE-RL July 1999 Radioactive Waste Management U S Department of Energy-Richland Operations Office Richland, Washington) requiring the reporting of waste inventories and space utilization for Hanford Tank Farm tanks.