The authors discus an efficient concrete technology toward highest advance rates in tunneling in unstable rocks at minimized labor input.

Purpose. The assessment of options for opening and mining the upper tier of Oleniy Ruchey apatite nepheline deposits and technological solutions development taking into account geomechanical calculations of open pit slopes and benches stability, both on the marginal contour and when changing the design values of the slope parameters, open pit benches and the stability safety factor to establish the marginal maximum accepted under the condition of the values stability.Methodology. Searching for technological solutions of mining is based on the method of mining and geometric analysis of the deposit upper tier, comparison, generalization, systematization, analytical calculations, 3D parametric modeling, threedimen sional numerical modeling of stressstrain state and the rock mass stability by the finite element method.findings. According to the research results, the optimal development of mining operations has been proposed for an option providing for the minimum overburden ratio. The parameters of the highwall slopes and their elements on the marginal contour and the development of the deposit are recommended according to the option that provides the maximum possible involvement in the development of the adjacent rock mass and pit reserves mining within the existing limits of the open pit mining tap.originality. It consists in feasibility evaluation of using a rational technology for the development of mining operations accord ing to the option that provides for the minimum overburden ratio and possible mining development schemes for mining open pit reserves with an assessment of the possibility of internal dumping during the development of an open pit.Practical value. The calculations show that for the conditions of a lying side, the normative factor of the slope stability on the marginal contour can be ensured only if they are bank slopes worked along the weakening surfaces, whose cutting should not be permitted.

The diagrams for supporting workings by floor and roof bolts are considered, which allow to reduce the swelling of floor rocks and manifestations of rock pressure. The degree of influence of mining and engineering factors on the bolting effectiveness of workings is established.

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