Ammosov North-Eastern Federal University, Yakutsk, Russia:

A. N. Petrov, Head of a Chair, Candidate of Engineering Sciences
A. M. Alekseev, Senior Lecturer

Zapadnaya Gold Mining Limited, Yakutsk, Russia:
S. G. Kolesnikov, Head of Technological Department

Chersky Institute of Mining of the North, Siberian Branch, Russian Academy of Sciences, Yakutsk, Russia:
D. N. Petrov, Researcher, Candidate of Engineering Sciences, petrovdn74@mail.ru

This article describes technological schemes of accessing, development and stoping at lower horizons of Badran gold ore deposit in Yakutia. The underground mining experience is discussed. It is found that strength properties of enclosing rock mass drop with mining transition to deeper levels due to higher temperature and moisture content of rocks. A scheme is proposed for gaining access to lower horizons via an inclined shaft at an angle of 8–10°. The included self-propelled equipment allows higher productivity of labor owing to better capacity, mobility and multifunctional performance. In order to improve geomechanical conditions, in-stone development of ore body is recommended, with location of haulage drifts in stable foot wall rocks. Drivage of development drifts in stronger enclosing rocks will reduce the cost of support and maintenance and will abate the risk of accidents due to the infl uence of stoping. The main mining system is room-and-pillar mining with reinforcement and dry rock fill. For ore body areas of increased thickness, a variant of slicing with concrete floor construction is off ered. The specified stoping design allows mining with minimum loss and dilution. In general, the recommended technological solutions on extraction of ore reserves underneath permafrost levels at Badran deposit are aimed at improving effi ciency of mining in the sever environment of the Extreme North.

1. Neobutov G. P., Grinev V. G. Mining of ore deposits using the freezing filling in permafrost conditions : Monograph. Yakutsk : Yakutsk Science Center of the Siberian Branch of Russian Academy of Sciences, 1997. 104 p.
2. Petrov A. N., Petrov D. N. Improvement of the technique of ice-rock backfill in permafrost zones. Gornyy Zhurnal. 2015. No. 4. pp. 26–28. DOI: 10.17580/gzh.2015.04.05
3. Neobutov, G. P., Zubkov V. P., Petrov D. N. Assessment of the stability of the outcrop of rock mass in the conditions of underground development of cryolite zone deposits. Nauchnoe obozrenie. 2014. No. 8. pp. 941–944.
4. Izakson V. Yu., Grinev V. G., Samokhin A. V., Neobutov G. P., Zubkov V. P., Shkulev S. P. Assessment of geomechanical state of massif during the deposit mining in cryolitic zone. Fiziko-tekhnicheskie problemy razrabotki poleznykh iskopaemykh. 1993. No. 3. pp. 26–29.
5. Klishin V. I., Vlasov V. N. Problems of Uderground Mining of Kimberlite Deposits in Permafrost Zone. Permafrost Engineering: Proceedings of the 5^th International Symposium. Vol. 2. Yakutsk, 2002. pp. 12–15. (in English)
6. Pavlov A. M., Semenov Yu. M., Sosnovskiy L. I. Evaluation of parameters of stable pillars and room roofs in underlay lode mining in cryogenic zones in terms of the irokindinsky gold deposit. Gornyy informatsionno-analiticheskiy byulleten. 2014. No. 10. pp. 21–27.
7. Iudin M. M. About the influence of geocryological conditions on the processes of underground mining of ore deposits of the North. Gornyy informatsionno-analiticheskiy byulleten. 2011. Special issue No. 10. pp. 97–101.
8. Coil D., Lester M., Higman B. Gold Mining Methods. Ground truth trekking. Gold Mining Methods. Last Modified: 4th November 2014. Available at: http://www.groundtruthtrekking.org/Issues/MetalsMining/GoldMiningMethods.html (accessed: 30.08.2016).
9. Scales M. One of a kind. Lac des iles palladium mine expands. Canadian Mining Journal. February/March 2012. pp. 22–24.
10. The Björkdal Mine. Underground mining. Horn International. Available at: http://hornonline.com/thebjorkdal-mine (accessed: 30.08.2016).
11. Lizunkin V. M., Matveev A. E. Technology of mining of steeply-falling closely-placed uranium low-yield veins. Vestnik Zabaykalskogo gosudarstvennogo universiteta. 2011. No. 9. pp. 91–94.
12. Sokolov I. V., Smirnov A. A., Antipin Yu. G., Baranovskiy K. V. The technology of ascending mining a golden ore deposit employing dry filling. Gornyy informatsionno-analiticheskiy byulleten. 2015. No. 9. pp. 14–19.
13. Petrov A. N., Nikiforov L. A. Experience of underground mining of gold-antimony deposit Sentachan. Gornyy informatsionno-analiticheskiy byulleten. 2011. Special issue No. 10. pp. 185–191.
14. Putzmeister SPM 4210 WETKRET and Mixkret 4 Working at Rasvumchorr Underground Mine in Russia. Available at : http://www.mining-technology.com/contractors/roofing/putzmeister-2/pressputzmeisterrasvumchorr.html (accessed: 30.08.2016).