Corrosion Control Measures For Liquid Radioactive Waste Storage Tanks At The Savannah River Site

The Savannah River Site has stored radioactive wastes in large, underground, carbon steel tanks for approximately 60 years. An assessment of potential degradation mechanisms determined that the tanks may be vulnerable to nitrate- induced pitting corrosion and stress corrosion cracking. Controls on the solution chemistry and temperature of the wastes are in place to mitigate these mechanisms. These controls are based upon a series of experiments performed using simulated solutions on materials used for construction of the tanks. The technical bases and evolution of these controls is presented in this paper.