Nowadays mining prosperity depends largely on the stability of underground structures. It is then necessary to know the configuration of the deposits. Which means analyze and understand the behavior of enclosing land during Operation Ore. The Geotechnical study is based on the behavioral aspects of rheological and mechanical response of the rock mass Mine Draa Sfar, the digging of galleries and various infrastructures works necessary for mining. Thus, the comparison between usual failure criteria and geo-mechanical characterization of the rock matrix focused on the peculiarity of the facies of the mine that are attacked by the schistosity and other structural deformations. Thus, we first conducted a sizing of major operating structures according to Long Holes method. It is, in fact, operating rooms. Then, it was verified the stability of proposed designs for different infrastructure galleries. Then it was important to consider support systems for mining these components. Therefore, we must return to examine the stability of blocks generated by the joints families found after a statistical statement processing discontinuity plans on ground. But still, it is necessary to treat the execution schedule sizes by first developing an operating sequence that takes into account the area of influence of mining openings and keep a stable production rate. Finally, the profitability study has helped to rule this project in terms of financial value. Indeed, economic performance indicators (NPV), (IRR) and (CAF) have clearly shown that the project is highly profitable.