ABSTRACT: The studies related the deposition of the spoil piles, which is obtained by mining excavation in openpit mines, and the reclamation of the depositional areas are very important to overcome the induceddestruction of the nature. A significant part of these studies is the investigation of the slope stability ofspoil piles. In this study, slope stability analyses have been performed for the spoil piles of the Sekköyopen pit mine in Muğla-Milas. Experimental results indicated that the spoil material includes nearlyequal amount of coarse and fine grains, and has low plasticity index. With the purpose of determiningthe mobilized shear strength parameters at the time of failure, back analyses have been performed forthe spoil pile failures observed in the study area. The comparison of data from the back analyses and thelaboratory tests reveals that residual strength values were mobilized at the time of failure for the spoilmaterial. By considering the data obtained and the field observations, one and multi-bench economicaland safe slope design analyses have been performed for the spoil piles in the study area in accordancewith the rules in the regulation on reclamation of the sites destructed by mining applications. Accordingto the results of the analyses for 10, 20 and 30 m slope heights, 20-40° and 19° overall slope angle valueswere determined for one and multi-bench slopes, respectively