This paper deals with the extensive laboratory studies and field trial carried out at one of the running opencast mines to evaluate the feasibility of disposing pond ash(PA) as a backfill material along with overburden (OB) in an environment friendly manner. Physico-mechanical, elemental composition, and geo-technical properties of PA, OB and its admixture was determined in laboratory. It was observed that mixing PA with OB alters its size gradation, density, angle of repose, permeability, compressibility, compaction etc. Stability analysis for different section of the final stage internal dumps revealed that a FoS of more than the statutory value of 1.5 was obtained in most of the sections. Field studies on a pilot scale PA-OB mix dump model of 15 m height to observe its behavior during pre and post monsoon period was observed. It was found out the pilot dump did not encounter much vertical movement at the top of the pilot dump, an average movement of 700 mm was observed at the toe and crest of the adjacent dump under the influence of one monsoon. The finding of this study will enlighten the practicing mining engineers about the pros and cons of dumping PA with OB in an opencast mineout.