Disposal of Chromite Ore Processing Residue (COPR) is a major concern from an environmental point of view because it consists mainly of Cr(VI) in addition to Cr(III). Cr(VI) is more soluble and mobile when compared to Cr(III). The study primarily concentrated on treatment of COPR using solidification and stabilization (S/S) process. Prior to the S/S process, there was a need for reduction of Cr(VI) fraction present in COPR to Cr(III). In order to reduce Cr(VI) fraction present in COPR to Cr(III), experiments were carried with a variety of reducing agents like Calcium Polysulfide, Silica Gel, Gaur Gum and an optimum dose was arrived at. Further, the chemically treated COPR was solidified with Ordinary Portland Cement along with lime as the binding material in various mix proportions, with Water/COPR plus binder ratio of 0.55. The performance of the above reducing agents and S/S process was verified by conducting leaching tests like Toxicity Characteristic Leaching Procedure, Extraction Procedure Toxicity Test, and American Nuclear Society Leach Test. With these tests, the leaching process in acidic and neutral mediums and the influence of the size of the waste particles on the reduction process as well as leaching were studied. The economics of the process was also arrived at based on cost of chemicals (reducing agents) and materials (cement, lime) needed for remediation of one tonne of COPR. © 2014 American Institute of Chemical Engineers Environ Prog, 34: 674–680, 2015