The deposit of copper ore in Bor occurs in East Serbia in hydro-thermal zone. Actually the open cast mine takes up the area of 1.2 km2 with slopes of different depth attaining up to 200 m. The reconstruction of the present open cast is foreseen to more considerable proportions and to a depth of about 350 m from the surface.
In the period of 1967–1969 broad investigations by geological and seismic methods has been started in order to obtain fundamental data for designing new open cast working, and particularly to determine the optimum inclinations of slopes of the workings.
The present paper deals with problems concerning methods and results of the investigations. Methods used for calculation of stability are based on results of all investigations, especially of those carried out in the terrain.