ALZAMIR Science and Production Association, Kemerovo, Russia:

A. V. Aikin, Chief Project Engineer, Andrey.Aykin@yandex.ru
D. F. Zayatdinov, CEO

Irokinda LLC, Irokinda, Russia:
E. D. Pryanichnikov, Chief Engineer

R. V. Shikhametov, Director for Mining

The engineering design development for Irokinda gold mining project required selection and justification of mining system parameters for Serebryakovskaya vein. Irokinda gold ore deposit occurs in the north of Buryatia. The local high-mountain terrain is dominated by the Alpine-type hillsides with slope inclinations up to 30–40°; the actual elevations of watersheds are more than 2000 m; the relative altitudes over the valley bottoms is up to 1000 m. Based on the studies into the physical and mechanical properties of the vein and enclosing rock mass, the roof rock stability diagram is plotted, which enables selecting the geometrical parameters of a stoping area by the preset height of the stoping level, and the design procedure is developed for the intermediate pillars. The inspection results of the parameters of stoping areas after the 3D stress–strain modeling of rock mass in Map3D show that the analytically obtained parameters of stoping areas ensure safe gold mining in reef drifting; in fringe drifting it is possible that critical stresses arise in pillars and promote their fracture, and sizes of the pillars should be increased by 20% as against their theoretical values. The use of the reasonable mining system parameters can reduce ore extraction time, enhance mining safety and lower ore dilution.
The authors appreciate participation of Dr. Eng., Prof. V. A. Eremenko, Director of the Research Center for Applied Geomechanics and Convergent Technologies in Mining and NUST MISIS College of Mining, the Project Engineers of the Center and Post-Graduate Students Ch. V. Khazhyylay, A. R. Umarov, A. M. Yanbekov and M. A. Kosyreva, and NITS IGD CEO A. S. Pozolotin in this study.

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