Mining Institute, Kola Science Center, Russian Academy of Sciences, Apatity, Russia:

E. V. Gromov, Senior Researcher, Candidate of Engineering Sciences, evgromov@list.ru
O. V. Belogorodtsev, Researcher
A. V. Zemtsovskiy, Head of Laboratory, Candidate of Engineering Sciences

North-Western Phosphorous Company, Kirovsk, Russia:
E. E. Shchetinin, Senior Executive Vice-Director—Technical Officer

The article describes the current state of mineral resources available for the Acron group of companies in the Murmansk Region. The authors discuss the results of the studies performed by the Mining Institute, KSC RAS under the supervision of Academician N. N. Melnikov, and aimed at ensuring safe and efficient development of the Oleniy Ruchey and Partomchorr apatite–nepheline deposits of the Khibiny group. The main parameters of an ecologically balanced mining and processing technology were substantiated for the reserves of the Partomchorr deposit located near the planned National Park, and the minimum break-even price for the concentrate was determined, which allows returning to the future development of the deposit. The geotechnology was substantiated for mining in 12/15 sections of level + 180/0 m in the Oleniy Ruchey deposit. The computer simulation in mining and geological information system MINEFRAME has allowed performing a feasibility study and substantiating the deposit opening-up parameters with using crushing and conveyor systems, which provide rapid step-by-step extraction of mineral reserves and reduction in priority investment in construction. The Oleniy Ruchey deposit is noted to be classified as rockburst-hazardous from a depth of 400 m downward, which causes high risks of dynamic rock pressure during underground mining. For the geomechanical assessment of the deposit mining conditions, the numerical volumetric model was designed and the stress–strain state of the rock mass was calculated using the finite element method implemented in the Sigma GT software. The safe parameters of the transition from open stoping to mining with caving, safe dimensions of the mine structure elements, and the mining sequence are substantiated. The correction of the mining method parameters during development of irregular separately lying ore zones has been proposed, which provides for backfilling using caved rocks. The possible options for the mining development are considered, ensuring a rapid increase in production capacity both of the upper levels and the whole mine.
The authors express their gratitude to fellows of the Mining Institute, Kola Science Center RAS: S. V. Lukichev, Doctor of Engineering Sciences, Director of the Institute, A. A. Kozyrev, Doctor of Engineering Sciences, Professor, Head of Rock Mechanics Department, I. E. Semenova, Candidate of Engineering Sciences, Head of Rockburst Hazard prediction Sector and E. E. Khomkin, Junior Researcher for the help in the study implementation and fruitful discussions.

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