Selection and assessment of mining equipment used in open pit rock mines relies chiefly on estimates of overall exploitation cost. The rational arrangement of mining equipment and systems comprising loading machines, haul trucks and crushing plants should be preceded by a thorough analysis of technical and economic aspects, such as investment outlays and the costs of further exploitation, which largely determine the costs of mining operations and the deposit value. Additionally, the operational parameters of the mining equipment ought to be considered. In this study, a universal set of evaluation criteria has been developed, and an evaluation method has been applied for the selection of surface mining equipment and the processing system to be operated in specific mining conditions, defined by the user. The objective of this study is to develop and apply the new methodology of multi-criteria selection of open pit rock mining equipment based on multiple criteria decision-making (MCDM) procedures, to enable the optimization of loading, handling and crushing processes. The methodology, underpinned by the principles of MCDM, provides the dedicated ranking procedures, including the ELECTRE III. The applied methodology allows the alternative options (variants) to be ranked accordingly. Ultimately, a more universal methodology is developed, applicable in other surface mines where geological and mining conditions are similar. It may prove particularly useful in selection and performance assessment of mining equipment and process line configurations in mining of low-quality rock deposits. Therefore, we undertook to develop universal criteria and applications for the selection and performance assessment of process machines for surface mines, taking into account environmental aspects as well as deposit quality.

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The production performance of mining and also construction equipment (like haul trucks, excavators, loaders, crushing and screening equipment) depends on its availability and utilisation states. Thus, it is necessary to determine the mean availability and structure utilisation of machinery systems with the aim to improve the same. At the same time, a detailed analysis of machinery operation data can result in a more effective management of mining plant operations and the mining process itself. Determination of operational state indices and their individual components allows to start preventive actions, resulting in the improvement of the organisation of work of the entire mine machinery system. Moreover, the future technical state of machines operated in surface mining is closely related to the current state and depends also on the events that have occurred in the extraction system. The analysis of dependability parameters can have a significant impact on decision-making, related both to the processes of use and maintenance, and, primarily, to all main operational processes of the mine. Different mines follow different terms and maintain different information. The only common information in most of them concerns the availability and utilisation of mining and construction equipment, which might be useful. There is a need to develop proper feedback and to define terms, factors and indices related to mining equipment. Below follows an analysis of selected operational parameters and the mean availability in the process of using the mining and construction equipment. This type of analyses help determine the operational potential of every element in the engineering system, understood as the ability to perform work processes. The analyses also illustrate how the reliability parameters change with the durability of the operated machinery. This makes it possible to identify the machines with the highest and lowest damage rates and such analyses can form the basis for the creation of optimised machine systems.

The article presents an analysis of the influence of selected operating environment parameters on the operation of a technological system in a mine and examines the profitability of exploiting a deposit of low quality. A model based on a cyclical transportation system in a surface limestone mine, developed in the Haulsim software, served to evaluate—from an economic perspective—several material transportation scenarios depending on the quality of the deposit. A discrete simulation of machine operation allowed a detailed analysis of the technological, operating and economic parameters for selected solutions. The results may be the basis for a decision to begin or to resign from mineral extraction. The simulation results demonstrate that maintaining the operating environment in good technical condition positively influences machine operating cycle times, the required total time of the transportation task and the operating costs. The analysis was performed for the production period of one full year, allowing for the effective work and technological downtimes. This approach allowed the usefulness of the model to be demonstrated in evaluating not only the effectiveness of individual technological procedures but also its economic aspect, related to a decision on the exploitation of “difficult” deposits.

The paper highlights the results of a study that examined the employees' expertise andawareness of occupational hazards in their work environment. The research involved a survey conductedin the form of a short questionnaire among employees responsible for loading and hauling of excavatedmaterial in an opencast mine. Among 23 major hazards that were thus identified, there were global hazards(affecting the entire mining process) as well as local, task-specific hazards. Depending on the number ofresponses, 10 local and 3 global hazards were identified in the analyzed area, involving noise, stress anddust. Active participation of the crew in the risk identification process helped in the assessment of theircriticality levels, according to employees carrying out various task, highlighting the benefits of suchapproach for effective work safety management in a mining company. The conducted researchdemonstrated yet another goal to be achieved - i.e. the comparison of criticality levels of hazards asidentified by employees and those reported in occupational risk assessment reports in the mine.

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Rational solution for mining equipment based on the use of haul trucks, excavators, wheel loaders and crunchers should result from thorough analysis of technical and economic issues – both cost-related and exploitational - which can have a crucial impact on the cost of minerals extraction. Moreover mining equipment should be selected with consideration for all vital parameters in specific exploitational conditions and even the exploiter’s preferences. This selection should consider hitherto disregarded criteria, such as mean availability and structure utilization of machinery systems with the aim to improve the same. Methodology presented in the paper illustrates practical application of MCDM and one particular method of this type – the Analytical Hierarchy Process (AHP) – for resolving the problem in specific exploitational conditions of mineral resource in surface mining AHP method covers a multi-criteria approach based on a compensation strategy to model preferences and assuming variant comparability. Taking into account the preferences of the evaluator, which determine the subjectivity of comparative evaluation, is the core of the multi-criteria approach, which treats such preferences Considering the above issues, the following paper is an attempt to develop new and universal criteria as well as a method of evaluation and selection of means of mining equipment for mineral resource surface mines.

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