sungun mine

In this paper, stability analysis of the slopes on Sungun mine was investigated. Sungun mine located in East Azerbaijan province, 45 km north of Varzaghan city. In order to investigate the stability coefficient and the rate of displacement on the slopes, three sections were selected and analyzed by numerical and equilibrium methods using SLIDE and UDEC models. The results showed that the coefficient of slope stability against failure in static conditions is more than 1.4 and in dynamic conditions with cosidering of the design based acceleration (DBA) of 0.35 g, it will be in the range of 0.92 to 1.2. In the case of applying acceleration of 0.42 g, the safety coefficient decreased to 0.8 and 1.05 and in most of the mine area, especially by Janbu method, it will be less than 1 and occurance of instability in wide range of the studied mine area is possible. However, in the extraction benches even with the application acceleration of 0.35 g, a limited chance of failure is possible. Based on the numerical analysis results, the displacements in the western part of the mine (downstream of the mine slopes) are generally higher than the eastern part of the mine. The maximum dynamic displacement in DBA of 0.42 g will be happen at section 2 (middle part of the mine) with the amount of more than 40 cm. In the entire of the mine area, the occurrence of toppling failure is dominant.

Mining is regarded as one of the most polluting sources of environment due to the production of toxic acid wastewater. Considering the environmental impacts of mining in the stage of mine production planning development can potentially reduce the harmful effects of this industry on the environment. In this research, attentions have been paid to the planning of production in Sungun Copper mine looking at parameters and environmental impacts. For this propose, field studies were conducted and chemical analysis, as well as exploratory and mapping data for planning of environmental production have been carried out, and various sections of ore have been evaluated with a view of the production of waste water. After modeling the mineral deposit and providing a block model, toxic elements content was determined for each block using the Kriging method, and the weight and effect of the blocks were determined using the entropy method. The block model in contrast to conventional production planning methods that include only grade of minerals, considers the wastewater production capacity of each block and its degree of pollution. Finally, by designing a production planning based on the environmental impacts of the toxic elements prevailing in Sungun copper mine eight operational phases were designed for this deposit. In this planning, blocks in the first pitt with a mean pollution level of 1141 and those in the final pit with an average of 52 have been found to represent the highest and lowest potential, respectively, producing harmful wastewater into the environment.

Determination of slope angle is one of the most important parameters in open pit mine design. With low slope angles, stripping is considerably increased. On the other hand, selection of high slope angles may reduce safety and causes failure. Therefore, to prevent slope failure and high stripping, a compromise is necessary to select an optimum slope angle. There are several methods of analyzing the stability of open pit slopes such as limit equilibrium methods, empirical methods and numerical methods. In this paper, FLAC software has been applied to determine the overall slope angles in the different parts of Sungun copper mine. For analyzing the slope, five vertical sections with a proper coverage of all parts of the mine, were considered. For the aforesaid sections on the static loading, stability analysis was performed for different slope angles and then with the help of regression analysis a relationship was developed between safety factor and angle of slope for each of the sections separately. In this research work, on the basis of geo-mechanical characteristics of rock mass, a factor of safety of 1.2 was selected. On the basis of obtained results, mine slope in the south and south-west was detected to be critical. Based on this analysis, slope angle of the mine, in the south and south-west parts and for the north and north-east part, was considered to be 25 and 37 degrees respectively. Sensitivity analysis was fulfilled for each section to study the role of cohesive strength and internal friction angle. It was considered that section 4800 (west) and section 4800 (east) respectively have the highest and lowest sensitivity to variations of cohesion. Also it was seen that section 4800(east) and section NE-SW respectively have the highest and lowest sensitivity to variations of internal friction angle.