Mine reclamation is an integral part of the mineral development process. The selection of land use after the mine closure is a difficult decision, which is complicated further because of the variety of parameters that must be taken into account trying to provide the local community with a viable development plan. Conventional methods used for reclamation planning are characterised by the lack of data integration and by time-consuming analysis. In this study, we propose a spatial decision-support system (SDSS) that minimises these problems, as data integration and analysis are offered within one computerised environment. A geographical information system and multi-criteria decision-making methods, based on binary integer linear programming models, have been integrated to select the appropriate land use in different parts of a post-mining area taking into account social, technical, economic, environmental and safety criteria. The proposed SDSS was used for the selection of the optimal landscape reclamation strategy of the Amynteon lignite surface mine located at West Macedonia Lignite Centre, Northern Greece. On the basis of developed mine maps, the model variables are assessed and incorporated into the objective optimisation function. Emphasis is placed on the spatial diversification of the model variables. The application demonstrates that the decision-support system allows the mining company to determine in an efficient way the specific land use (agricultural land, forest, recreational area and industrial zone) that is considered the most suitable for every part of the study area.
This study aims to assess the production of cellular micro-concrete, consisting of quarry dust, calcareous fly ash, cement, and aluminum powder as aerating agent. The proposed mixture design methodology is based on a Box–Behnken fractional factorial experimental design. Testing of specimens included compressive and flexural strength, density, water absorption, and thermal conductivity measurements. Results indicate that density is a characteristic property which determines all the measured properties. Aerating agent to cement and fly ash ratio has the strongest effect on all the measured properties. The developed methodology is a valuable tool for the production of cellular micro-concrete with predetermined properties by utilizing large amounts of quarry dust.
1 December 2012 in International Journal of Mining, Reclamation and Environment
Surface mining operations can adversely impact the environment. The size and nature of earth-moving works carried out for the exploitation of mineral deposits can cause severe environmental problems unless the mining company plans and implements an effective environmental protection and land reclamation programme. Such a programme starts from the early stages of deposit exploration and continues for many years after the closure of the mine. The type and magnitude of environmental damage associated with surface mining projects are closely related to various site-specific, physical, chemical, ecological, socioeconomic and cultural characteristics, which must be thoroughly identified, analysed and modelled. The goal of this study is to provide decision-makers with information that is necessary for assessing the contribution of a proposed project to national, regional and local development and welfare. Using this approach, project proponents and supervising authorities are able to communicate effectively with public interest groups. Speedy and effective communication between all stakeholders engenders mutual cooperation and collaboration while minimising political damage, all of which will minimise risks that may lead to financial losses or cancellation of the project in its entirely. This article is a review of the main regulatory aspects of public involvement in decision-making involving environmental management of surface mining projects with special emphasis on the Aarhus Convention, an initiative of UN Economic Commission for Europe. The study cites several cases of ‘contract-based’ agreements between mining companies, supervising authorities and the public that have successfully addressed various environmental and socioeconomic issues. Furthermore, this article proposes a methodology for predicting the budget that is required for financing environmental protection and land reclamation works throughout the entire life of the mine, taking into account numerous technical and economic parameters as well as the associated uncertainty. The methodology proposed in this study may be useful during negotiations of environmental management plans for new or for existing mining activities.
The number of abandoned mines is continuously increasing in the world. The sustainable exploitation of these abandoned mines is a top priority globally. Pit lakes created in abandoned mining sites provide benefits and present risks for the mining region. This paper presents a methodology to assess the mining and natural hazards related to pit lakes. The proposed methodology framework is based on well-established and internationally accepted risk management standards and allows the assessment of the long-term stability of pit lakes. Potential ground movements, water pollution, fire hazards are presented, and their impact evaluated based on feedback and international experience. The methodology was applied for 13 European pit lakes created in former European coal and lignite mines. A risk assessment of the Most lake was carried out, using qualitative and a weighted probabilistic approach that considers the overall and the individual effect of identified mining and natural hazards. Results showed that the main potential hazards are the ground movements, slope stability, and flooding.
This paper presents the results of a geotechnical investigation regarding the slope stability in a pit lake, emphasizing the impact of water level variations. Advanced analysis techniques were utilized for this study. The research was performed by using fully coupled flow-deformation analyses. For the fully coupled approach, Bishop’s effective-stress equation was used, and for the description of soil hydraulic behavior, the Van Genuchten’s model was applied. The analysis of slope stability associated with reservoir water level changes revealed that the slope tended to become unstable as the water level decreased; the stability factor was negatively related to the rate of water level reduction. Concerning the water level fluctuations, the analyses revealed that the soil mass seemed to become less stable as the rate of water level change increased. Under a specific range of rates of water level variation, the safety factor became higher as the number of fluctuations increased. Additionally, the simulation results concerning the water level rising indicate that the pressure due to the external water level acts on the slope surface with a positive impact on the stability factor. The results obtained reflect the effects under a specific site condition, but they can be used as a reference for evaluating slope stability in a pit lake design.
Waste concrete is the most predominant constituent material among construction and demolition waste. Current waste concrete recycling is limited to the use of recycled concrete aggregates as a road-base material and less as aggregates in new concrete mixes. Further, the production of recycled concrete aggregates results in the generation of a high amount of fines, consisting mainly of cement paste particles. Hence, this study aims to produce the cement mortars using the upgraded recycled concrete aggregates (sand granulometry) for the total replacement of natural aggregates and recycled concrete fines activated through a thermal treatment method as a partial cement substitution material. Cement mortar specimens were tested for their compressive and flexural strength, density and water absorption performance. The results showed that the combined usage of upgraded recycled concrete sand for total replacement of primary crushed sand and recycled concrete fines as partial cement replacement material is a promising option to produce cement mortars.