Analysis of SX farm leak histories -- Historical leak model (HLM)

摘要

This report uses readily available historical information to better define the volume, chemical composition, and Cs-137/Sr-90 amounts for leaks that have occurred in the past for tanks SX-108, SX-109, SX-111, and SX-112. In particular a Historical Leak Model (HLM) is developed that is a month by month reconciliation of tank levels, fill records, and calculated boil-off rates for these tanks. These four tanks (among others) were used from 1956 to 1975 for storage of high-level waste from the Redox process at Hanford. During much of these tanks operational histories, inventory losses because of evaporative cooling could have effectively masked any volume loss due to leak. However, careful comparison with reported tank levels during certain periods clearly show unaccounted volume losses for many tanks.