Selection of accessing and development schemes for extracting reserves of ore body 2 in Irtysh deposit

Purpose. Justification and selection of a rational scheme for accessing the second ore body of the Irtysh deposit based on a technical and economic comparison of its adopted competitive options. Methods. The main mining, geological and engineering requirements for selecting the scheme for accessing the Irtysh field are considered to achieve the goal. Three competitive accessing options are proposed on the basis of project regulatory documents and geotechnological features of the ore body. The optimal scheme of accessing was suggested taking into account the volumes of mining and preparatory works and averaging of the metal content in the ore by the method of technical and economic comparison. Findings. Analysis of the accessing schemes was performed for deposits similar in the geological conditions and represented by fragmented ore bodies. The advantages and disadvantages of 3 competitive access options are reviewed in detail. The technological and economic feasibility of excavation of ore body 2 reserves has been substantiated, i.e. of accessing them by fringedrifts between the Irtysh and Vspomogatel'naya mines on the upper horizons of the deposit. It is established that the difference in the volume of capital works (CW) and preparatory works (PW) is 45640 m3 in favor of accessing ore body 2 by fringedrifts between the Irtysh and Vspomogatel'naya mines. At the same time, the volumes of CW and PW at the initial and final stages of development are much lower than in the case of accessing by a transport ramp from the surface. The change in the average content of copper, lead and zinc with the simultaneous development of the Osnovnaya Deposit and the South-Eastern Deposit in the lower horizons of the field has been calculated. Originality. For the conditions of ore body 2 of the Irtysh deposit, planned for development in accordance with the proposed access, it was found that despite the decrease in the copper content in the saleable ore, the lead content in the saleable ore will increase to 0.49% and zinc content, respectively, to 3.83%. Practical implications. Mining of ore body 2 according to the recommended accessing scheme with a minimum amount of mining will allow to raise the productivity of the Irtysh mine to 600 thousand tons per year during the period 2018 – 2026, as well as to increase the extraction of lead and zinc.