Polar Division, Norilsk Nickel Mining and Metallurgical Company (Norilsk, Russia):

Anokhin A. G., Director, Geodynamic Safety Center, Candidate of Engineering Sciences, Phone: +7 (3919) 37-19-78
Marysyuk V. P., Chief Engineer, Geodynamic Safety Center, Candidate of Engineering Sciences
Nagovitsyn Yu. N., Head of Department, Geodynamic Safety Center

VNIMI Inter-Industry Scientific Center (Saint-Petersburg, Russia):
Andreev A. A., Head of Norilsk Division
Mulev S. N., Head of Geophysical Research Laboratory

A separatory block (SB-1) was formed in Oktyabrsky Mine as a result of the counter-advancing longitudinal fronts of stoping in the east wing of mine-1 and west wing of mine-2. The length of SB-1 was 720 m. When SB-1 width became 64 m, it was further extracted with two diverging latitude-oriented fronts. As a consequence of overlapping of the abutment pressure zones generated by the counter-advancing longitudinal and, then, transverse mining fronts, the separatory block became a geodynamic hazard source for the entire period of extraction; the most hazardous events of rock pressure, including the events with severe after-effects, took place within the boundaries of the separatory block. Aside from the geometry of the mined-out void, this was contributed to by the complicated mining-and-geological conditions—pronounced tectonic faulting that generated blocky hierarchy in the structure of the ore and rock mass. As a result, in the background of the higher mining-induced rock pressure, local stress concentration zones arose in some tectonic blocks. Based on the analysis of the real-life mine-technical, mining-and-geological and geomechanical conditions, the article presents validation and estimation of mining sequence at the south end of the separatory block in Oktyabrsky Mine, as well as the developed and implemented extraction project for belt 9/9 (extraction unit) using the proposed technology with advanced stoping, which allowed sensible decrease in the stress level of the ore body for its follow-on safe mining.

1. RD 06-329-99. Instruktsiya po bezopasnomu vedeniyu gornykh rabot na rudnykh i nerudnykh mestorozhdeniyakh, obektakh stroitelstva podzemnykh sooruzheniy, sklonnykh i opasnykh po gornym udaram (DDD 06-329-99. Instruction on safe carrying out of mine operations at ore and non-metallic deposits, objects of construction of underground facilities, inclined and prone to bounces). Moscow, 2000.
2. Ukazaniya po bezopasnomu vedeniyu gornykh rabot na Talnakhskom i Oktyabrskom mestorozhdeniyakh, sklonnykh i opasnykh k gornym udaram (Guidances on safe carrying out of mine operations at Talnakh and Oktyabrskoe deposits, inclined and prone to bounces). Norilsk, 2007.