WVNS Tank Farm Process Support: Corrosion evaluation of Waste Storage Tank 8D-2 under simulated sludge washing conditions

摘要

Radioactive waste solutions resulting from spent fuel reprocessing operations at West Valley Nuclear Services (WVNS), West Valley, New York, have been stored in two carbon steel underground storage tanks for several years. Constructed in 1964, these tanks are designated as Tanks 8D-1 and 8D-2. Tank 8D-1 has contained about 64,000 kg of cesium-loaded zeolite and about 380 kL of a relatively dilute solution of sodium nitrite and sodium hydroxide; Tank 8D-2 has contained about 2120 kL of waste slurry resulting from spent fuel reprocessing operations. Over the next few years, plans for permanent disposal of the tank contents will be implemented. Until the waste is removed, the integrity of the tanks must be maintained. A corrosion support program is being conducted at Pacific Northwest National Laboratory (PNNL) to investigate internal and external corrosion of the tanks and to make recommendations accordingly. Tank 8D-1 was selected as the focus for an evaluation of external corrosion, and results of that investigation are provided in Mackey and Westerman. Tank 8D-2 was investigated for internal corrosion. The results of the corrosion study for Tank 8D-2 are given in this report.