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Harmful effects caused by the water flow through various constructions (dams, embankments, etc.) are successfully solved by installing the various filter layers. The basic functions of filter layers are fast water evacuation with preventing the internal erosion and removal of small soil particles. These filter layers are usually made of coarse-grained materials (sand, gravel, stone aggregates), but in addition to the natural materials, the artificial geosynthetic materials are increasingly used. This paper presents the basic filter rules that need to be followed in order to perform a successful design of various filtration and drainage systems.

Mining induced the ground subsidence and consequently, damages on objects above excavation works is a serious problem all over the world. In this paper, a new approach for subsidence and deformation prediction based on the stochastic Pataric-Stojanovic method is presented. Since the calculation using the equations of this method is very complex, the original computer program package with the title MITSOUKO has been purposely designed. The MITSOUKO program enables calculating at any point of the land surface and representing the results owing to the possibility of their integration and further processing in the Geographical Information System (GIS). The components of the GIS are used to realize the spatial analysis.

The occurrence of subsidence caused by the underground coal mining may be a complex process that causes damage to the environment. In the last century, there was a significant development in prediction methods for calculating the surface subsidence. In this paper, a new prediction method has been developed to calculate subsidence by combining a stochastic model of the ground movements and Geographical Information System (GIS). All the subsidence calculations are implemented by an original program package MITSOUKO, where the components of the GIS are used to fulfil the spatial analysis. This subsidence prediction technique has been applied to calculate the ground movements resulting from excavating 21 mining panels that are mined successively in the coal mine ''Rembas''-Resavica, Serbia. Details of movement were sequentially predicted and simulated in terms of years exploitation. Predictive calculation of the undermined terrain displacement parameters by the stochastic method and integration into the GIS is a powerful risk management tool.

Defining the pushbacks at the open pit is one of the most important planning activities. Designing the pushbacks is the first step in a long-term planning of production at the open pit where the production is planned. Despite the existence of a large number of software, used for different mathematical algorithms for optimization the open pits, a role of mining engineers is still a key one in development the mining plans. The work presents the results of conducted impact analysis of selection the optimum pushbacks on the project economy. Based on the results, the importance of correct selection of pushbacks can be concluded for achieving the basic goal of the mining operation - the Net Present Value Maximization (NPV).

The problem of exploitation planning refers to A criterion used to optimize the open pit. In spite of sophisticated algorithms, the problem of optimization is always an economic problem, within which the procedures for assessment the necessary economic parameters are defined. Every ore body is different, but the main steps in planning an open pit, when the main objective is to make a profit, are developed by the same principle. When planning the copper ore exploitation, the final economic result depends on the overall technological process of copper obtaining copper as a final product.This work present an economic analysis of the copper ore exploitation on the Cerovo Primarno-Drenova deposit for athe nnual capacity of flotation processing of 6.0 and 12.0 million tons, using the software for economic analysis and long-term planning of open pits Whittle surface (Dassault Systèmes-Geovia).

In today’s financial and environmental climate, it is imperative to develop the robust projects with good economics. Successful business in conditions of limited resources is impossible without analyzing all the technical and economic parameters and scenarios of sustainable operation. In this sense, it requires the application of mathematical algorithms implemented in the contemporary software tools able to efficiently provide the effective troubleshooting of design in complex conditions of modern mining. This paper, an example of the open pit South Mining District Majdanpek, shows the importance of planning and design the ore exploitation in achieving the maximum net present value (NPV).

Mining is the process of extracting a naturally occurring material from the earth to derive a profit. Whether the company make a profit or not depends on many economic parameters, among which the most important are the metal prices on the world market and realized operating costs in the process of exploitation. This work presents the influence of copper price change and value of operating costs on the generated cash flows, i.e. profit, in the case of the open pit South Mining District, which operates within the Copper Mine Majdanpek, Serbia.

This paper gives the stability analysis of the Western and Eastern external landfill at the Open Pit Gacko, together with the problems that occurred during the last field visit.

Traditional methods of ore mining in the underground mine Jama Bor cannot be applied to the ore body Borska reka for several reasons: the position of the ore body to the terrain surface, mining infrastructure and proximity of settlements, physical-mechanical properties of rocks in the ore body, economic viability, ore recovery, etc. In addition to the above, it should be taken into account that this is the ore body with low copper content, so it is necessary to choose a method for mass excavation. Due to these reasons, the mining method of ore was selected with backfilling of excavation area with paste backfill of certain physical-mechanical properties. This work will be present the test results of uniaxial compressive strength of paste backfill, as one of the most important properties and how this parameter varies depending on the change in balance of components of which a paste backfill is made. Tests were conducted on a number of different recipes for paste backfills and the backfill with 5% cement, 24% water and 71% uncycloned flotation tailings was selected as the best one.

This paper describes the process of waste flue gas desulphurization (FGD) formed in combustion [1] of brown coal from Ugljevik. For the purposes of development the technology of waste flue gas desulphurization (W) in coal combustion from Ugljevik, the experimental development of technology was approached in the laboratory conditions. For experimental work, an apparatus was designed for combustion the coal samples in a closed system with projected measuring points for measuring the composition of waste flue gases. The wet method was used for desulphurization FGD, i.e. the absorption of sulfur dioxide (SO2) in the limestone suspension. The advantage of this desulphurization method is as follows: possession a large amount of raw material for S absorption, relative small investments to prepare the absorption suspension, very simple method of S absorption of EDC, verified in operation [2], high efficiency, obtaining a potentially useful by-product, possibility of application in large plants. .

This paper presents the results of a part of technological tests, whose aim was to determine the optimum techno-economic conditions for the flotation concentration of ore from the deposit Tenka-3 - North Mining District, Copper Mine Majdanpek. The given view refers to testing the effects of collectors NaIPX, 3418 A and 5500 AP, as well as the pulp pH value on the quality of concentrate from the primary flotation process. It was found that the majority of copper, gold and silver in the primary concentrate is obtained using the collector AP 5500. In addition, a better quality of primary concentrate was obtained at higher pH values of pulp in the tested pH range (10.0 - 11.5).

Analyzing the slope stability of work levels, final slopes and slope system was carried out in the area of the open pit 'Gacko' according to the criteria required by the law of the Republic Srpska. This paper presents a comparative analysis of slope stability with three numerical methods by Bishop, Yanbu and Morgenstern-Price in various pore pressures ru=0, ru=0.2 ru=0.4 and critical factor of influence the stress reduction at the same pore pressures that were already mentioned. The analyses of slope stability were carried out with the existing and newly obtained data. The software packages SLIDE v6.0 and PHASE2 v8.0 of company ROCSCIENCE were used for calculation methods. The expected result is approximately the same value for the safety coefficient (Fs) and critical factor of influence the stress reduction (SRF) only at that point of analysis.

This paper presents one possible approach for resolving some important issues related to the stability of underground rock structures at higher depths. The analysis is focused on forecast the behavior of rock mass before performing the mining excavation at deeper levels of the ore body 'Borska Reka'. Regardless of extensive previous research of the ore body 'Borska reka' and necessary parameters obtained for modeling of stress and strain that occur under the influence of mining excavation, additionally the estimation state of stress in the rock massif is also done. The stability analysis is shown for the roadway at the level XVII and forecast their stability for deeper level. As the result, it is expected that the level of uncertainty and risk associated with many identified geomechanical risks with management of rock massif will be reduced.

The work presents a consideration of a long-term development of the open pit North Mining District in terms of achieving maximum profit for the planned capacity of 5 million tons of copper ore annually, using the modern software Whittle for strategic planning of production. Software provides the ability to achieve a positive development of cash flow and maximum net present value by optimization the excavation limit and long-term mining dynamics. For planned technical and economic parameters, which are the input data for analysis, the boundary of the open pit is obtained for the service life of 26 years, and the value of the net present value is $ 252,591,906.

The paper analyzes the possibility of increasing capacity at the Open Pit South Mining District in terms of achieving maximum net present value. The analysis is based on the movement of discounted cash flow during exploitation period of 18 years. The modern approach of designing the open pits was used for this consideration using the software Whittle and Gemcom Gems. The analysis showed a positive trend of discounted cash flow from the third year until the end of analyzed period in achieving the net present value in the amount of 596 252 546 $.

The use of backfill in underground mining is increased due to a need for systematic backfilling the mine openings and workings. Backfilling is applied in order to prevent fires and explosions, improve the mine ventilation, improve the rock stability, reduce the subsidence effects on surface, as well as for economical and environmental factors. Sources of materials are usually from mining industry (e.g. fly ash, gypsum, slag, infertile overburden, tailings, filter dust, residues from mineral processing) or other industries. The ore body Bor River of the Bor Copper Mines is planned to be exploited by the sublevel stopping method. In order to ensure greater efficiency in the exploitation of the ore body, it is proposed, after the excavation of chambers, to move on to the excavation of the main pillars. To ensure the stability of the excavation area, it is necessary to fill the excavated chambers with material of good physical and mechanical properties. For this purpose, a possibility of filling the chambers with backfilling consisted of flotation tailings, small amount of cement and water, will be tested. This paper reviews the basic requirements of backfilling that will be applied in the excavated chambers.

Scripts are essentially the macros containing instructions for data manipulation in the form of mathematical and logical operations performed for the block model data. In order to create the useful filters and key indices, it is important to have a good understanding of expressions and how to use them. Expressions are simple formulae that can be created to define selection criteria for data in the workspace. There are two types of expressions: math expressions, which always result in a numeric value, and logical expressions, which always result in a true or false condition. Math expressions consist of up to three components: field specifiers, constants, and math operators. Logical expressions are made up of two math expressions separated by a logical operator.

This paper presents stress and strain analysis in massif during exploitation of out-of-balance coal layers in the BCM Bogovina. Behavior of the surrounding rock mass was tested during application of large diameter boreholes exploitation. Based on the proposed solutions for stope geometry and known geological conditions in deposit, physical and mechanical properties of coal and surrounding massif, the numerical analysis of the stress and strain of excavation area and surrounding massif was done. Numerical modeling of excavation area behavior was done using the software package Phase2, whose calculations are based on the finite element method. The analysis, conducted in this paper, has shown that there is a possibility for applying this kind of excavation in terms of stability the rock mass.

In order to secure the underground stope in the ore body, 'T1', the supporting of excavated area is carried out. The supporting, in this case, is carried out by means of anchors of type SWELLEX and SN, M-20 in a combination with the resin LOKSET RESIN CAPSULES, and reinforcement mesh, which is applied with the layer of torkret concrete. This work presents the results of testing the carrying capacity of anchors in a given ore body 'T1'.

Defining the stress rock massif is essential for design of underground facilities and methods of mining in the mines. Assessment the value of stress state of rock massif and rock strength in the various loads allows rational design. This is of particular importance when sizing columns, determining the extent of excavation, the cross-sections of underground rooms in problems with rock bursts and others. This paper briefly gives the basic methods of determining the rock massif stress as part of a study that is aimed to facilitate development of engineering-geological and geomechanical model of the rock massif along the tunnel route under the flotation tailing dump Veliki Krivelj and underground facilities in Jama Bor as the numerical analysis could be applied of the stress-strain state of rocks around the built facilities.

Research the stability of underground structures that are almost done, can be divided into the frameworks of theoretical processing, basic laboratory analyses and information on previous experiences in the exploitation of deep deposits and, as such, they can serve as a reference for more detailed research. In this paper, the example of the ore body 'Borska Reka' in the underground mine Jama Bor, shows one of the ways to get the reliable data on the working environment that can be used to model the rock mass. Therefore, the results will provide a realistic assessment the stability of the analyzed structures.

Long-term planning in the mining industry has one main goal: maximizing the value that is realized by excavation and processing of mineral resources. When designing the open pits, determining the stages of development the mining operations, (eng. Pushback) is one of the important factors in the process of long-term production planning. Using the different scientific methods and mathematical algorithms underlying the operation of modern software for strategic planning of production, it is possible to control the business economy. This work presents the influence of the open pit development phase of the South Mining District Majdanpek on significant increase the net present value.

This work studies the effect of both linear and non-linear dependence between the horizontal reaction F on the basis of displacement the wall D. The soil is adopted only as a material with an angle of internal friction and without cohesion.

This paper analyzes the impact of vertical uniformly distributed load P(t) and currently acting impulse So on the appearance of dynamic pressure on a supporting wall.

In this paper, the process of finite element analysis of deep underground salt caverns was described with geometry and material properties related to caverns in the salt mine Tetima-Tuzla, B&H. The 3D model was built based on ultrasound measurement and CAD modelling of planar geometry data. Nonlinear finite element analysis was performed resulting in stresses and deformations data necessary for assessment of cavern stability and time dependent behaviour.

This paper describes the principle of development the structural models of rocks, based on which the geomechanical model rock massif is developed, to which the applied numerical methods of stress analysis can be applied in solving the practical problems in the field of underground and surface mining of mineral raw materials.

This paper presents the relationship between the Atterberg limits and soil compaction parameters obtained by the correlation-regression analysis. The relations between the liquid limit wl, plastic limit wp, maximum dry density rdmax and optimum moisture content wopt are obtained on the basis of the results of laboratory tests measured on a large number of samples of clay core earthfill dams Rovni, Selova, Prvonek and Barje. The regression and correlation analysis were obtained empirical equations and diagrams. Based on the obtained, the value of the optimum moisture content and maximum dry density of knowing the Atterberg limits of plasticity can be estimated.

The need to expand the capacity of the flotation Field I is necessary due to increase the capacity of the Flotation Plant Veliki Krivelj. Based on the geotechnical data from previous investigations and as a proposal for displacement the existing Dam 2 to increase the capacity of the flotation Field 1, an analysis the effect of flotation and rock mass on the route of the new Krivelj River collector was carried out using the software package Phase 2.