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Reserves of apatite-nepheline ores in the Khibina massif, which are being worked by the underground method using a system of forced collapse in stages, are represented by ore bodies with a dip of up to 25-30 ~ for an average horizontal thickness of 180-200 m and extent of 1800-2000 m. Ores of average strength having a uniform structure are broken up by systems of fractures into large and small blocks, and under load are inclined to brittle failure. The deposits are being worked horizontally in separate areas, blocks 70 m high, 150 m wide along the strike, and with a length across the strike over the entire horizontal thickness of the ore body. As the ore reserves are extracted, an open cleared space is formed in the shape of trenches, filled with the collapsed overlying rocks of the hanging wall. The maximum depth of the mine workings is 350-400 m at the present time.The stress state of the rock mass is determined by the action of horizontal tectonic forces and the weight of the overlying rock. The size of the tectonic component may reach 600 kg-sec/cm 2 [1], and its destructive effect on an element of the system at shallow mineworking depths, on the order of 70-100 m from the surface, is the predominant influence. IL is manifested in the form of scaling, exfoliation, and cracking of the rocks. In the latter case, slabs of rock weighing up to 3-4 kg often snap off the edge of the mineworking with an explosionllke sound, which is a great danger to the workers. The destructive effect of the gravitational component begins to appear at a depth of~S00-350 m.As the ore body is extracted beneath the hanging wall, the overhang of the cantilever of the overlying rocks causes a counterpressure on the rock mass being worked, the concentration coefficient of which may reach 3.0-5.0 before the collapse of the cantilever [2, 3]. In such cases, the gravitational component at the working depth reached causes stresses in the elements of the system which are equal to or exceed the compressive strength limits of the rock.The combined action of tectonic and gravitational forces is especially unfavorable for the stability of the most important element of the system, the bottom of the block, which provides for the execution of the main and auxiliary processes during ore extraction. Up to 60-70% of the total volume of the block working is located at the bottom, and this dissection is the cause of severe strain In its elements. Under conditions of the combined action of tectonic and gravitational forces, cases of crushing occur at the bottom of the blocks and even smallrock shocks, which comprise a safety hazard in the mining work and cause an increase in the loss of ore broken out and additional expenses in erecting reinforcement and sinking new shafts into the bottom. Thus, today, these expenses have already reached 20 kopecks/ton of ore extracted, i.e., 12% of its cost. But in some cases, even the most reliable forms of support cannot prevent the destruction of the bottom element for the construction being used. In zones of high rock...

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Methods used in planning and managing underground mining in pits have come into conflict with new requirements for intensifying production since they are mainly governed by the level of competence, experience, and professlonal intuition of the miner and the person taking a decision.Due to the considerable structural complexity and variance of structural provisions for production processes in winning operations with underground ore mining, periodic changes in the position of the work front in space and time during working, existing methods for planning and management do not make it possible to consider and evaluate the whole aggregate of basic links between component parts of the object being managed in both a static and dynamic condition. Absence or limitation of information about the main relationships for reaction of the production structures and subsystems with the rock mass and between them leads to adoption of subjective solutions by mine managers. The tendency of a deterioration in mine geological and geomechanlcal conditions for underground mining with the increasing onset of high productivity, but extensive technology for driving and mining operations, increases the degree of economic and production risk in the stage of choosing and substantiating production decisions. BASIC ASSUMPTIONS FOR SYSTEM PLANNINGCreation of qualitatively new methods for planning and management of underground mining technology for hard economic minerals is possible on the principles of a systematic approach with use of a computer [i, 2]. This approach makes it possible to consider as large technical systems mining in a deposit or an individual part of it under static and dynamic conditions [3][4][5]. This is characterized by a single intentional combination of technical means and existence of a management unit, by the compatibility of elements of the structure, and by the properties and degree of efficiency of functioning in time.In the first stage a structural model is formed for the technology of underground mining of ore reserves. At its base are primary structural units of production processes which are an assembly of workings and structures interconnected in space. Structural modules of a different level of hierarchy are formed form primary units both for individual production processes of winning and for the combination of them. Among significant structural element characteristics for the system are their linear parameters in planes of sections X, Y, and Z, coordinates of the spatial location in relation to ore body contacts, values for the required energy, material and personnel resources, production indices in a unit of time, and boundaries of the functional effect in space. The properties isolated for structural elements corresponds to mine-geological and Eeomechanical conditions of their functioning.In accordance with the principles of a systematic approach the ore body and surrounding rock, the atmosphere and hydrosphere in contact with structural elements, as component parts of the management object, are considered as...