Mining Life Cycle Research Articles

Hydrological classification of mine pit lakes using modelling experiments

With the growing global prevalence of open-pit mining activities, there is an increasing necessity for sustainable mine life cycle plans with an early outlook towards mine closure. A major consideration in mine closure planning is the potential formation of lakes in the mine void and how these “pit lakes” can be managed to minimise risks and, if possible, create benefits. Understanding the long-term interactions between pit lakes, groundwater, and surface water systems is essential for that purpose. While numerous site-specific studies have been undertaken, there have been no studies that aim to provide a general, broadly applicable understanding of how pit lake hydrology relates to geographical context, and no efforts to hydrologically classify pit lakes using geographical criteria. This research employs an integrated generic pit lake water balance model to examine mine pit lake interactions with the surrounding surface water and groundwater. Simulating 243 scenarios, the influence of five input factors (climate, hydraulic conductivity, regional groundwater level, catchment area and pit slope) on pit lake behaviour up to 6000 years beyond the closure of the mine was considered. The assessment focused on four pit lake hydrological attributes once the system reached equilibrium: water level, time to equilibrium, the fraction of days where the pit recharges groundwater, and the fraction of days where there is surface overflow from the lake. All scenarios were assigned to one of five hydrological classes based on the interactions between the pit lake and the surrounding surface water and groundwater. Our findings show that, in many contexts, general data on climate type and subsurface hydraulic conductivity can yield reliable predictions of a pit lake's long-term hydrological classification without having to develop a detailed, site-specific pit lake model. The classification needs improvements in non-arid climates where inter-annual variation in rainfall is pronounced. The pit lake classification is particularly valuable for first-pass risk assessments to determine whether site-specific modelling is required.

Identification and Characterization of Reclaimed and Underclaimed Mine Features Using Lidar and Temporal Remote Sensing Methods within the Coastal Plain Uranium Mining Region of Texas

We developed a spatiotemporal mapping approach utilizing multiple techniques for distinguishing and mapping known reclaimed mine sites from “unreclaimed” mine sites in a historic uranium mining district along the South Texas Coastal Plains. Lidar laser scanning penetrates the vegetation canopy to expose anthropogenic modifications to the landscape. The Lidar analysis (bare earth elevation surface, slope, topographic contours, topographic textures, and overland-flow hydrography) revealed mine features. Visual interpretation of Landsat imagery and time-series analysis augmented the Lidar analysis revealing the temporal life cycle of mining. The combination of bare earth texture with time-lapse and time-series analyses revealed areas of disturbance for reclaimed mines. The spatiotemporal mapping approach proved to be most useful in identifying and characterizing the known mine pit and pile features, reclamation status, and areas of disturbance due to mining. Two mine waste volume estimation methods resulted in a 21% difference indicating that although the approach helps to map mine features and areas of mining disturbance for the purposes of mine land inventory, additional information is needed to improve the estimation of buried mine waste at reclaimed mine sites.

Dynamics of corporate social responsibility (CSR) during mineral exploration: Evidence from Eastern Region, Ghana

How are decisions around Corporate Social Responsibility (CSR) arrived at in the mining sector, particularly in Ghana? To date, the literature on mining and development in the region has mostly analysed individual interventions made in the name of CSR and critiqued the case for embracing it. These assessments, however, very crucially overlook exploration, an essential phase of the mine lifecycle, during which inaugural dialogues are initiated with local communities that ultimately have a bearing on CSR strategy over the long term. This paper examines the dynamics of CSR at the exploration phase of mining projects, surveys local communities’ perspectives on the subject, and assesses the actions of international mineral exploration companies. It does so using semi-structured interviews and focus group discussions with policymakers, exploration company officials, and inhabitants of and leaders in mining communities in the Eastern Region of Ghana. The findings suggest that while mineral exploration companies use CSR as platform to showcase their commitments to social and environmental standards, they have made little efforts to understand the socio-cultural, economic and political dynamics of their host communities. It was also revealed that host communities are not afforded the opportunity to provide inputs into decisions on how CSR should be operationalised. The paper calls for a revision of policies and regulations governing mining in Ghana by making CSR a key requirement for mineral exploration companies seeking to undertake exploration or prospecting activities in the country.

Life Cycle Mining Deformation Monitoring and Analysis Using Sentinel-1 and Radarsat-2 InSAR Time Series

The life cycle of mining results in various patterns of surface deformation as it progresses through development, production, and reclamation. Therefore, the spatial–temporal patterns of ground deformation provide a crucial indicator to understand the mining activities, related geohazards, and environmental restoration. This study investigates the decadal deformation (2012–2022) of three coal mines during different stages of mines’ life cycles in Henan, China, using radar interferometry with Radarsat-2 and Sentinel-1 data. The results reveal multiple deformation patterns across different areas: the Changcun mine area changed from ground subsidence to uplift following the termination of exploitation in 2016; the Xiadian mine area has been continuously developing over the past decade, resulting in a cumulative subsidence of 55.6 mm; and the Liyuan mine area exhibits surface rebound at a rate of 7.9 mm/year since its closure in 2007. We also probe the mining geometry of the production process by using a rectangular model. This study highlights the significance of long-term InSAR observations and deformation modeling in elucidating the mining operation dynamics of small mining zones in their production, transition, and post-closure periods, thereby facilitating the management of small-scale mining.

Knowledge synthesis on the mine life cycle and the mining value chain to address climate change

The escalating demands for mineral commodities driven by population growth and energy transition are prompting the mining industry to intensify extraction efforts and respond to the imperatives of climate change. Concurrently, the pressure of climate change-related concerns necessitates mining operations to enhance their environmental, economic, and social sustainability. This review aims to synthesize the overlapping knowledge from the mine life cycle (MLC) and the mining value chain (MVC) to distill the practices and strategies for mining's climate action as an extended producer responsibility. The first focus of this study was to examine the concepts of MLC and MVC and their interconnections. Subsequently, an in-depth literature review was conducted to map each stage of the MLC to the value chain regarding mining's climate action and future requirements. Our work pinpointed specific climate-related challenges and opportunities at every juncture, underscoring the importance of strategic mine planning with climate objectives, design for closure, renewables deployment, green mining technologies, agile and lean operations, risk mitigation for premature mine closure, and climate information transparency.

Dynamics of carbon sequestration in vegetation affected by large-scale surface coal mining and subsequent restoration

Surface coal development activities include mining and ecological restoration, which significantly impact regional carbon sinks. Quantifying the dynamic impacts on carbon sequestration in vegetation (VCS) during coal development activities has been challenging. Here, we provided a novel approach to assess the dynamics of VCS affected by large-scale surface coal mining and subsequent restoration. This approach effectively overcomes the limitations imposed by the lack of finer scale and long-time series data through scale transformation. We found that mining activities directly decreased VCS by 384.63 Gg CO2, while restoration activities directly increased 192.51 Gg CO2 between 2001 and 2022. As of 2022, the deficit in VCS at the mining areas still had 1966.7 Gg CO2. The study highlights that complete restoration requires compensating not only for the loss in the year of destruction but also for the ongoing accumulation of losses throughout the mining lifecycle. The findings deepen insights into the intricate relationship between coal resource development and ecological environmental protection.

Coal mining and water resources: impacts, challenges, and strategies for sustainable environmental management

The intricate relationship between coal mining and water resources is discussed, as well as coal mining affects the quality and availability of water is highlighted. Coal deposits play a major role in energy production, and at the same time, coal mining causes adverse environmental effects. For this reason, the article is devoted to the study consequences of coal mining on water contamination and soil conditions. The investigation results show that coal mining causes dangerous and harmful particles to reach the surface of the water, degrades the soil, and causes chemical exposure. Hydrology and water quality throughout the mining lifecycle are influenced by such consequences, which can be observed across mining regions and under different extraction methods. In this regard, there exists a need for effective strategies and implementing best practices for mining operations, adopting preventive measures for acid mine drainage, and advanced water management techniques. Also, the experience of effective environmental management is discussed. Mining reclamation plans, adherence to specific standards, and the role of rocks selection in reclamation success are discussed. Considering the above balancing energy needs with sustainable environmental practices is crucial to ensuring the coexistence of mining and global water resources.

Social License, Mine Closure, and the Exploration Geologist

Editor’s note: The aim of the Geology and Mining series is to introduce early career professionals and students to various aspects of mineral exploration, development, and mining in order to share the experiences and insight of each author on the myriad of topics involved with the mineral industry and the ways in which geoscientists contribute to each. Abstract This paper describes the potential value that can be gained when exploration geologists, early in the project life cycle, contribute to aspects of project development that have historically been outside of their purview. Increasingly strong societal pressures are being directed toward exploration and mining to ensure (1) an enduring social license to operate is in place and (2) closure and postclosure mine liabilities are fully addressed and funded. These actions are consistent with the professional and ethical obligation of caring for human and ecological well-being over both the short and long term. The roles and responsibilities of exploration geologists are evolving as a result. A singular focus on searching for and assessing the nature of ore deposits from a technical perspective has expanded to include (1) contributing to building the foundation for a social license to operate and (2) capturing increasing amounts of data and information relevant to the full mine life cycle, up to and including the closure and postclosure phases of activity. These activities are additional to the traditional geologic role of the exploration geologist and will further enhance the value of an exploration project, despite the rare transition of an exploration target to an operating mine. This expanded role is critical for aligning industry and social values, strengthening trust in the mining industry, and enhancing the appeal of the mining industry as a desirable career option.

Optimizing coal mine planning and design for sustainable development in the context of mass exploitation of coal deposits

Sustainable mining practices is a concept that embeds the principles of sustainable development into the whole mine life-cycle, from exploration, extraction and processing through to mine closure. The optimization of coal mine planning and the developing a standardized design for its sustainable development is very challenging and requires more effort. The present research attempts to address the conditions of sustainability and necessary measures for sustainable development, thereby providing appropriate solutions for each stage of mining operation besides expressing the necessity of sustainable development integration at different stages of mining life cycle (MLC). The approach of systems engineering is essential to assist the sustainability goals which are integrated with the expected results. Hence a method depending more on systems engineering principles and optimization can be incorporated to attain better results. Several socio-environmental factors associated with sustainability depends on the geographic condition and few mining engineering considerations such as mine location, topography, coal seam characteristics and so on. These systems engineering approach can be further enhanced by incorporating tools like Geographic Information System (GIS), which provides more accuracy and precision of the geographic conditions of the site identified for the coal mining plan. In order to begin this way of approach towards the sustainability development and mining planning, the appropriate optimization parameters should be identified. The outcome of these optimization parameters can be also achieved by optimizing coal mining system models.

Identification and categorization of hazards in the mining industry: A systematic review of the literature

AbstractControl of OHS risks in the mining industry has been attracting increasing attention in recent years. Because of their great diversity in a complex system, hazards can be difficult to identify and classify, especially when system components interact. Risk cannot be managed successfully without comprehensive investigation of all its aspects. A coherent and integrated classification for identifying and categorizing all hazards is currently lacking in mining. We propose an integrated system classification of OHS hazards in mining based on our review of 44 studies retrieved using PRISMA. Considering Canadian and international standards, regulations and conventions, new hazard categories are proposed and hazard prevention is discussed from 12 perspectives: physical, chemical, biological, ergonomic, accident and psychosocial risks, as well as policy, legislation, management, design, geography, and uncertainty, with reference to each of the four phases of a typical mine life cycle, the hazards were shown in a portrait. This paper provides suitable categories based on rational data for creating a portrait in order to OHS hazards prevention in life cycle activity in mine.

Future‐proofing a local government authority for a post‐mining future

AbstractThe inevitable mine lifecycle sequences of the mining industry and the eventual closure of mines has dramatic impacts on mining communities. The complexities of mine closure and planning for a different future beyond mining demand prescient preparation, preferably long before mines close, to optimise community participation in planning and enhance change management opportunities. Convincing others of the usefulness of imagining a future that is so different from the status quo is challenging, and it is especially difficult bringing an entire community on a long‐term planning journey. The Shire of Coolgardie, a small Western Australian local government authority, has embarked on a long‐term mission to build economic and social resilience, shoring up funds that will assist the Shire to ride out the inevitable mine lifecycle sequences of and diversify its income bases. This article builds an evidence‐based approximation of the economic and social benefits of the initiatives accrued across the Shire, outlining the calculated risks taken by the Shire in its quest to ultimately reorient the local economy to one less dependent on mining income and employment. The article concludes with lessons learned and a discussion regarding the replicability of the successful initiatives for other local government authorities elsewhere, particularly in Australia where the legislative restrictions to generate own‐source revenues are so severely limiting.

A game theoretic decision-making approach to reduce mine closure risks throughout the mine-life cycle

ABSTRACT To align a post-mining site to the wants and needs of local communities and stakeholders, mine closure needs to consider criteria which may be difficult to value using conventional cost–benefit analysis. For example, criteria associated with the environment, socio-environmental relationships, health, and long-term sustainability. Game theory techniques are implemented to investigate how different stakeholder groups could act during mine closure planning and decision-making. Using game theory with sustainability criteria, this study proposes an innovative approach to analyze some key decisions throughout the mine life that affect closure. Non-cooperative game theory models are investigated by developing Nash equilibrium equations which are based on the change in environmental risk, economic potential, and impacts on company reputation. The modified equilibrium formulas can highlight the key sustainability criteria for multi-stakeholder closure planning and complex decision-making. The discussion explores how the developed model can assist mining stakeholders in understanding their position during the mine closure process. In all, the game theory and multiple criteria models can help structure and manage the complex closure risks throughout the mine life cycle.

Tools to improve mine closure: 10 years of research in integration of environment in the mine life cycle

Abstract Mine closure can be approached by several points of view, from the technical, engineering, ecological, up to social and governance aspects. The definition of a good mine closure should cover most, if not all, of these aspects. This article provides a review of technical and engineering-oriented research work as a partial answer to the question ‘what is good mine closure’. The article presents a ten-year research program realized in the framework of a Canada Research Chair in integration of environment in the mine life cycle. Research projects aimed at better planning mine closure and mine site reclamation from the early stages of a mining project life cycle are exposed as possible steps to strive for optimal mine waste management. At the exploration stage, geo-environmental characterization and modeling are proposed as tools to improve mine waste management planification. During mine operations, environmental desulfurization is suggested as a method to reduce environmental risks associated with sulfidic tailings and waste rock. Indeed, research has shown that acid mine drainage and metal leaching can be significantly limited via desulfurization. At the closure stage, desulfurized tailings can be used to replace at least part of natural materials used for reclamation cover systems. Research work done on other types of mine waste, such as waste rock and water treatment sludge, also show good potential for their reuse as closure material. All these tools can be integrated into the mine life cycle to better plan for closure, which ultimately will make mine closure more sustainable.

Research on low-carbon operation mode of coal mine based on life cycle

Based on the theoretical framework of the whole life cycle theory and the specific production process of underground mines, this research focuses on a comprehensive analysis of the carbon emission accounting boundaries and sources within the entire life cycle of underground mining. Furthermore, a robust carbon emission accounting model is developed specifically for the entire life cycle of coal production. Subsequently, a case study involving an actual coal mine production scenario is conducted, wherein the model is utilized for analysis and calculation purposes. The comprehensive analysis and calculation results reveal that electricity usage constitutes the primary source of carbon emissions within coal mines, closely followed by methane escape and greenhouse gas emissions resulting from fossil fuel combustion. Based on these findings, the research then proposes strategies for low-carbon operations and the implementation of carbon reduction technologies in coal mines. By conducting a detailed analysis of the carbon emission accounting within the whole life cycle of underground mining and providing concrete findings and practical recommendations, this paper contributes to the understanding and management of carbon emissions in the coal production sector.

Life cycle assessment of coal mines of diverse scales over time in China

Coal mining has important detrimental effects on the environment and human health. By the end of 2022, China mined more than 4 billion tons of raw coal, and coal mining contributed to adverse environmental impacts. The objective of this work is to evaluate the environmental impacts emanated from coal mines in different periods (construction period, production period and closing period) and to find the relationship between coal mine scale and ecological impacts. This study uses coal mines that produce 0.45 Mt/a (considered a medium sized mine), 3 Mt/a and 8 Mt/a (both classified as large mines in this study) and a 12 Mt/a extra-large coal mine. Based on the time dimension, the mine life cycle was classified into construction, production and closing period, and the life cycle assessment method was used to conduct environmental assessment. The main influencing substances and key processes were tracked. The results indicated that mining engineering and gangue are the main factors affecting the construction and production periods of coal mines. Freshwater ecotoxicity, marine ecotoxicity, and human toxicity are the main environmental effects of coal produce, and they are mostly brought up by the release of hazardous elements like copper, chromium, zinc, nickel, and copper. Furan, formaldehyde, and chromium emissions during mine closure can be effectively reduced through environmental compensation, however coal mines' environmental compensation during mine closure is minimal. The environmental impact of coal mines producing 3 Mt and 8 Mt annually is minimal. The environmental impact of 0.45 Mt/a and 3 Mt/a coal mines is more prominent in the construction period. The pollutant discharge throughout the production phase, particularly the metal leaching discharge from gangue, needs to receive more attention from the 8 Mt/a and 12 Mt/a coal mines. Additionally, the larger the scale of coal mine production, the greater the proportion of the total environmental impact in the production stage.

Groundwater vulnerability to pollution in degraded coal mining areas: modifying the DRASTIC method using the factor of exploitation impact on land surface

Mining activities such as underground exploitation of hard coal deposits and open cast mining are strong factors on groundwater depending on mine life cycle phases. The impact of coal mining activities on groundwater have been reported from many countries. In this case, a vulnerability assessment was conducted base on standard DRASTIC method and its modification DRASTIC MINE (DRASTICM) method. In order to take into account, the impact of mining activities, a new parameter was added which defined the impact of coal seams on the rock mass above, including the degree of its drainage and the range of its impact. In the standard DRASTIC method, the results indicate that groundwater vulnerability with high (38.6%) and very high occurrence classes (16.9% of the area), mostly covers the central part of the cast mine. In contrast, the reclaimed area of the excavation is a low-class area. The DRASTICM method increased the vulnerability index from 3 to 24 on 95% of the area, so a new vulnerability class of extremely high was delineated, which occurred in 1.6% of the area. This indicates areas that should be treated as a priority in order to avoid pollution, and in the final stage to plan activities in the field of the reclamation of mining areas. The results showed that groundwater vulnerability assessment in coal mining areas can be significantly improved.

Tree-level landscape transitions and changes in carbon storage throughout the mine life cycle

Opencast mining activities destroy native vegetation, directly impacting the carbon sequestration capacity of the regional ecosystem. Restoring tree species have significant impacts on carbon storage. However, changes in carbon storage across tree-level landscape and the impact of tree-level landscape transitions on carbon storage remain poorly described in the literature, and this information is urgently needed to support management decisions. In this study, we combined field data and remote sensing techniques to create field data-driven maps of the tree-level landscape. This enabled the assessment of carbon storage and quantification of the impact of tree-level landscape transitions on carbon storage. We founded that carbon storage rises in initial/stable stages, decreases in development stage during mining expansion and reclamation. The choice of restoration tree species significantly influenced carbon storage. Pinus tabuliformis-R. pseudoacacia accumulated more carbon storage, making it a more suitable model for ecological reclamation of Pingshuo opencast mine. Furthermore, changes in carbon storage are influenced by land-use policies. Land-use policies and reclamation efforts counterbalance carbon loss associated with construction. Various tree-level landscape transitions were examined, with Pinus tabuliformis transitions notably affecting carbon storage, offering insights for ecological reclamation planning. Our research provides a reference for carbon storage assessment in opencast mining areas, enhances understanding of carbon storage changes in mining areas, assists in formulating ecological reclamation plans, and contributes to the “dual‑carbon” goals and climate change mitigation.

Assessing impacts of mining on provisioning ecosystem services in a culturally diverse landscape of Western Cape York, Australia

ContextMitigating the impacts of mining on biodiversity and ecosystem services (ES) is critical for maintaining human wellbeing in mineral-rich landscapes. Environmental assessments and mitigation plans almost always consider impacts on biodiversity, yet few extend to the individual ES valued by local communities. As a result, mine site management, rehabilitation, and compensation activities may fail to prevent the loss of some ES, particularly those valued by remote Indigenous communities.ObjectivesWe seek to understand: (1) which ecosystems contain culturally significant plant species and where they are located in respect to mining areas; (2) whether areas containing large numbers of culturally significant plant species are protected under current environmental management plans focused on addressing biodiversity impacts, and; (3) which ES will be lost due to planned (and approved) future mining operations.MethodsWe consider a region rich in both natural capital and Indigenous culture–western Cape York Peninsula in northern Australia. We identify and map the distribution of ES that are both valued by local Indigenous communities and threatened by current and future bauxite mining including plants that have significant cultural value (e.g., for food and medicine), and compare them to areas currently protected from mining due to their biodiversity value.ResultsWe find that open woodlands contain the highest number of culturally significant plant species (32 species) compared to other vegetation types in the region. However, despite this, open woodlands are the least protected vegetation type from mining operations under current management plans and regulatory requirements.ConclusionsOur results illustrate the benefits ES provide for local Indigenous people, and that the areas set aside for biodiversity management will not compensate for expected ES losses. We discuss the need for a collaborative approach between industry, government, and Traditional Owners to capture and manage ES for local people throughout and beyond the mining lifecycle.

Systematic Review of GIS and Remote Sensing Applications for Assessing the Socioeconomic Impacts of Mining

As the mining industry expands, a comprehensive understanding of its socioeconomic risks and benefits is urgently needed. This paper systematically reviews 71 studies (1996–2021) that utilized spatially integrated approaches to evaluate socioeconomic mining impacts. The number of studies that utilize geographic information systems and remote sensing to study mining impacts increased from 2014 onwards. A framework was used to classify the mining impacts studied in the literature and all eight framework categories – Environment, Land, People, Community, Culture, Livelihoods, Infrastructure and Housing – were captured by the literature though Culture was least studied. Coal mining, active mining phase, Landsat data and classic remote sensing algorithms were most highlighted. Future research should focus on advancing geospatial technology like artificial intelligence (AI) to better capture intangible socioeconomic impacts, under-researched minerals and long-term mine lifecycle components. Spatially referenced social data can improve stakeholder involvement and support spatially explicit planning to ensure sustainability.

The Role of Economic Geologists in Water Management Related to Mining

Editor’s note: The aim of the Geology and Mining series is to introduce early career professionals and students to various aspects of mineral exploration, development, and mining in order to share the experiences and insight of each author on the myriad of topics involved with the mineral industry and the ways in which geoscientists contribute to each. Abstract Water has always been an important issue for mineral exploration and mining companies. In recent years, water-related issues have increasingly placed a constraint on the development of new projects, while mine closure issues have created billion-dollar legacies for governments. Water access and management creates not only project risks but also opportunities. There are opportunities for geoscientists to help mitigate water-related issues early in a development, particularly for the economic geologists who play a crucial role in gathering data and geologic understanding during the early mine life cycle. Geologists can contribute to the understanding of baseline water systems and help to mitigate the potential effects that mining may pose for local ecosystems and to the communities that depend on them.