The restoration of continuous surface lignite mines entering the closure phase is a long-term, complex and multidisciplinary project. During the evaluation of alternative restoration technologies, various environmental, technical, economic and social parameters are investigated. In this framework, for the selection of the lower risk restoration alternative, the analysis of the associated risks should be incorporated into the decision-making process. This work provides an overview of practical risk management problems and solutions in mining restoration projects. Moreover, it introduces a multi-criteria methodology for the improvement of the decision-making process in the evaluation of restoration alternatives and the selection of the optimal one, considering a continuous surface mining project. The proposed method is a combination of the analytical hierarchy process (AHP) for the quantification of risk factors and the technique for order of preference by similarity to ideal solution (TOPSIS) for the ranking of restoration alternatives based on a low risk approach. The results of the case study indicate that the proposed approach can be utilized as a low cost and easy-to-apply tool, appropriate for coal mining operators, managers and stakeholders involved in the planning and implementation of post-mining land restoration activities. Furthermore, the suggested methodology could be adopted to support the risk management needs in the restoration stage of complex surface mining projects.

Surface mining projects are vulnerable to natural hazards (earthquakes, floods, soil instabilities, and epidemic crises) which constitute the primary source of risks which affect the mining operations. In the framework of sustainable planning and development of such projects, the investigation of risk impacts is essential for taking the appropriate preventive measures before disastrous events appear in a mine. This paper proposes a methodology for the risk assessment of natural hazards in surface mining projects using the triangular Fuzzy Analytical Hierarchy Process (FAHP) for the determination of the probability of risk occurrence, combined with the Expected Value (EV) function, the Monte Carlo simulation, and the Program Evaluation Review Technique PERT method for making predictions of cost and time overruns. A case study of a hazardous event with impacts in the operations of a surface mine demonstrates the methodology as a flexible and low-cost tool for mining executives. This tool is useful in the planning stage of pre-disaster management projects in the mineral industry, considering mine sustainability views. The research work also investigates critical technical and economic aspects.

The sustainable transformation of surface coal mines aims to recover geoenvironmental and socioeconomic factors (ecosystems, landscape, soil, water, employment, etc.) related to extractive operations. The transition to sustainability starts when a mine enters the ageing/closing phase and includes large-scale technical activities for repurposing the mined sites. Moreover, circular economy practices and methods are introduced for efficient and socio-environmentally friendly use of mining wastes and non-exploited resources. The selection of a strategy for the sustainable transformation of a mine constitutes a complex decision-making framework presenting various practical problems. This paper provides a critical analysis concerning the definition of the transformation problems and suggests a decision-making methodology for the selection of a strategy for sustainability with a case study of a closing surface lignite mine in Greece. The methodology combines (a) a strengths–weaknesses–opportunities–threats (SWOT) analysis of the factors of critical importance for the evaluation of alternative strategies, and (b) the analytical hierarchy process (AHP) applied for the quantification and use of these factors for the selection of the most advantageous strategy. In this context, it is based on expert judgement. The results indicate that the proposed analysis can be used as a practical decision-making tool to resolve complex problems related to the mine closure and post-mining issues.

The closure of surface mines is a complex framework characterized by extended reclamations of post-mining sites towards an environmentally friendly and sustainable land-use system development with beneficial returns to society and the economy. The paper demonstrates the critical mine closure problem, draws research questions, and introduces the IDEF0 (Integrated DEFinition Function) process modelling method as a low-cost and easy development tool for use by mining experts to perform strategic planning of sustainable mine reclamation and repurposing projects. A case study for the method applied in a Greek lignite mine is presented.

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