Solidification/stabilization (S/S) technology was applied to a simulated sludge containing chromium. Leaching tests such as toxicity characteristic leaching procedure (TCLP), ANS 16.1 and multiple TCLP tests conducted on stabilized blocks showed that chromium was immobilized by the binder studied. A linear relationship was obtained between the cumulative fraction of chromium leached and time1/2 in the stabilized samples proving that chromium is leached by diffusion. The leachability indices obtained for the solidified materials satisfy the guidance value as per US Nuclear Regulatory Commission.