Mining Method Selection and Optimization of Transition from Open Pit to Underground in Combined Mining

Citation

Bakhtavar E, Oraee K & Shahriar K (2009) Mining Method Selection and Optimization of Transition from Open Pit to Underground in Combined Mining [Wybór metody wybierania oraz optymalizacja przejścia od kopalni odkrywkowych do podziemnych w podejściu mieszanym]. Archives of Mining Sciences, 54 (3), pp. 481-493. http://mining.archives.pl/index.php/content/view/307/49/lang,en/

Abstract
There are occasionally deposits with a potential of exploiting by a combined mining of open pit and underground. Hence, the most significant query emerges: where is the optimal transition depth from open pit to underground? In this study, in order to profitably select a single or combined mining of open pit and underground, as well as to determine optimal transition depth a methodology is presented. The model is established upon the economical block models of open pit and underground methods together with the Net Present Value (NPV)s gained by their mining. Main process in the model is economical comparison among several options of single and combined mining. To evaluate the model in detail, a hypothetical case is used. In this regard, among the all options a combined was selected that implying a height of 62.5 m as the optimal transition depth and the amount of 25.54 units of currency as the maximum total NPV achieved by the option.

Keywords
optimal transition depth; open pit; underground; single and combined mining; NPV; Coal mines and mining; Mining machinery

Journal
Archives of Mining Sciences: Volume 54, Issue 3