Solutions that simulated the compositions of saturated (J 13) and unsaturated (UZ) waters that can be found in the vicinity of Yucca Mountain were distilled to near dryness. The pH of both the condensates and residual solutions of J 13-based waters rose during the distillations, while the pH of both the condensates and residual solutions of UZ-based water experienced a large drop in pH during distillation, which could be caused by precipitation and slow redissolution of magnesium oxide solids. Samples of Alloy 22 immersed in condensates and residual solutions of UZ distillations exhibited general corrosion at rates ranging from 30-600 gm/year, and one sample exhibited pitting. Samples tested in solutions of 1000xJ 13 in which the pH was altered during testing showed an increase in corrosion rate over solutions of constant pH.