Copper export and mobility in acid mine drainage are difficult to understand with conventional approaches. Within this context, Cu isotopes could be a powerful tool and here we have examined the ...relative abundance of dissolved (<0.22 μm) Cu isotopes (δ65Cu) in the Meca River which is an outlet of the Tharsis mine, one of the largest abandoned mines of the Iberian Pyrite Belt, Spain. We followed the chemical and isotopic composition of the upstream and downstream points of the catchment during a 24-h diel cycle. Additional δ65Cu values were obtained from the tributary stream, suspended matter (>0.22 μm) and bed sediments samples. Our goals were to 1) assess Cu sources variability at the upstream point under contrasted hydrological conditions and 2) investigate the conservative vs. non conservative Cu behavior along a stream. Average δ65Cu values varied from −0.47 to −0.08‰ (n = 9) upstream and from −0.63 to −0.31‰ downstream (n = 7) demonstrating that Cu isotopes are heterogeneous over the diel cycle and along the Meca River. During dry conditions, at the upstream point of the Meca River the Cu isotopic composition was heavier which is in agreement with the preferential release of heavy isotopes during the oxidative dissolution of primary sulfides. The more negative values obtained during high water flow are explained by the contribution of soil and waste deposit weathering. Finally, a comparison of upstream vs. downstream Cu isotope composition is consistent with a conservative behavior of Cu, and isotope mass balance calculations estimate that 87% of dissolved Cu detected downstream originate from the Tharsis mine outlet. These interpretations were supported by thermodynamic modelling and sediment characterization data (X-ray diffraction, Raman Spectroscopy). Overall, based on contrasted hydrological conditions (dry vs flooded), and taking the advantage of isotope insensitivity to dilution, the present work demonstrates the efficiency of using the Cu isotopes approach for tracing sources and processes in the AMD regions.
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•We observe rapid change of both riverine Cu isotopic signature and water regime.•This change indicates the contribution of various sources within the mining area.•δ65Cu appears to be controlled by water regime rather than upstream processes.
The first intensive analysis of sense of place in American mining towns, Hard as the Rock Itself: Place and Identity in the American Mining Town provides rare insight into the struggles and rewards ...of life in these communities. David Robertson contends that these communities - often characterized in scholarly and literary works as derelict, as sources of debasing moral influence, and as scenes of environmental decay - have a strong and enduring sense of place and have even embraced some of the signs of so-called dereliction. Robertson documents the history of Toluca, Illinois; Cokedale, Colorado; and Picher, Oklahoma, from the mineral discovery phase through mine closure, telling for the first time how these century-old mining towns have survived and how sense of place has played a vital role. Acknowledging the hardships that mining's social, environmental, and economic legacies have created for current residents, Robertson argues that the industry's influences also have contributed to the creation of strong, cohesive communities in which residents have always identified with the severe landscape and challenging, but rewarding way of life. Robertson contends that the tough, unpretentious appearance of mining landscapes mirrors qualities that residents value in themselves, confirming that a strong sense of place in mining regions, as elsewhere, is not necessarily wedded to an attractive aesthetic or even to a thriving economy. Mining historians, geographers, and other students of place in the American landscape will find fascinating material in Hard As the Rock Itself.
Case studies examining the archaeological record of an overlooked mineral Salt, once a highly prized trade commodity essential for human survival, is often overlooked in research because it is ...invisible in the archaeological record. Salt in Eastern North America and the Caribbean: History and Archaeology brings salt back into archaeology, showing that it was valued as a dietary additive, had curative powers, and was a substance of political power and religious significance for Native Americans. Major salines were embedded in collective memories and oral traditions for thousands of years as places where physical and spiritual needs could be met. Ethnohistoric documents for many Indian cultures describe the uses of and taboos and other beliefs about salt. The volume is organized into two parts: Salt Histories and Salt in Society. Case studies from prehistory to post-Contact and from New York to Jamaica address what techniques were used to make salt, who was responsible for producing it, how it was used, the impact it had on settlement patterns and sociopolitical complexity, and how economies of salt changed after European contact. Noted salt archaeologist Heather McKillop provides commentary to conclude the volume.
A fire has been analyzed in a real underground coal mine, using a sublevel method, during an entire year. The study was focused on the collapsed area, reproducing a real mixture formed by coal, ...waste, and air gap. The analysis was done by means of an experimental analysis, a computational fuid dynamic model (CFD), and simulations using a mine ventilation software. Three scenarios were determined and studied regarding their influence on the evolution of the fire: (a) development of the fire without taking any action, (b) sealing off the affected areas, and (c) sealing and reducing the ventilation in the affected area and surrounding drifts. The study revealed the behavior of the fire in a real mine and the effectiveness of the main fire-fighting measures over time, verifying that none of the measures taken could eliminate the fire-induced in the collapsed area.
Mongolia’s mining sector, along with its environmental and social costs, have been the subject of prolonged and heated debate. This debate has often cast the country as either a victim of the ...‘resource curse’ or guilty of ‘resource nationalism’. In The State, Popular Mobilisation and Gold Mining in Mongolia, Dulam Bumochir aims to avoid the pitfalls of this debate by adopting an alternative theoretical approach. He focuses on the indigenous representations of nature, environment, economy, state and sovereignty that have triggered nationalist and statist responses to the mining boom. In doing so, he explores the ways in which these responses have shaped the apparently ‘neo-liberal’ policies of twenty-first century Mongolia, and the economy that has emerged from them, in the face of competing mining companies, protest movements, international donor organizations, economic downturn, and local and central government policies.
•Correlation analysis of water level data in explorational borehole groups.•Multivariate LSTM model for predicting the variation of water level.•IForest model for detecting water level variation ...anomalies.•Model calibration based on empirical threshold setting method.•Water inrush risk evaluation and early warning based on the coupled model of LSTM + IForest.
Water level variation of explorational boreholes in mining sites is one of the most direct representations of water inrush risk. Despite recent efforts on mine water inrush accident prediction based on various types of observation data including water level of boreholes using a wide range of machine learning models, the accuracy and timeliness of the prediction for major accidents are still unsatisfactory. In this study, a novel prediction method based on the analysis of water level variation anomalies in borehole groups is proposed using the coupled model of long short-time memory (LSTM) and Isolation forest (IForest). Multi-variate LSTM algorithm is firstly used to model the correlated time sequence water level data in the borehole group, followed by the full extraction of the data variation feature based on the combination of variables including the prediction error being used as inputs of the IForest algorithm. As a result, anomalous variations of the data are detected as possible precursors of water inrush accident. Finally, a set of water inrush risk level grading rule is established based on the number of simultaneous anomalous data instances being detected within a borehole group. The results obtained for the water inrush accident in Xingdong coal mine demonstrate extraordinary timeliness and high accuracy as high water-inrush risk warning is issued for more than 2 days earlier than the time of actual sighting of the accident with very few false alarms being caused throughout the period of the testing dataset. This study provides an innovative solution to the low prediction accuracy and slow responding speed during major water inrush accidents of existing methods. The major parameters of the proposed coupled model of LSTM + IForest can also be easily calibrated based on traditional empirical methods for the best performance, allowing the method to be widely applied in various mining conditions.
Analysis of a Historical Accident in a Spanish Coal Mine Sanmiquel-Pera, Lluís; Bascompta, Marc; Anticoi, Hernán Francisco
International journal of environmental research and public health,
09/2019, Volume:
16, Issue:
19
Journal Article, Publication
Peer reviewed
Open access
There has been a long history of coal mine accidents and these, usually, involve serious injuries, fatalities, and the destruction of facilities. In the seventies, an explosion killed 28 miners in a ...Spanish coal mine. This paper gives insight into the main factors of the accident by means of the causation mode, using two well-known alternatives: (1) the method from the Spanish Instituto Nacional de Seguridad y Salud en el Trabajo (INSST), where the causes and circumstances of the accident are classified into immediate causes and basic causes, and (2) the Feyer and Williamson method, where the classification is done using precursor events and contributing factors. The analysis identifies the lessons to be learned from the disaster. Both methods have given very similar results, verifying the goodness of the analysis. Methane emissions due to a variation in the exploitation method, the electrical installation, and a lack of safety procedures and training were the main causes of the accident. These findings explain the real causes of this accident and can be very valuable for the prevention of future accidents.
Cemented paste backfill (CPB) is accepted as the optimal backfilling material for many underground mines. However, the lack of in-stope backfill pressure data poses fundamental problems from both ...operational and research standpoints. In response to the requirement for in situ data, a comprehensive field instrumentation project has been conducted. Results are presented here for two stopes at the Cayeli Mine, where geotechnical instruments were installed at the barricades and throughout the stopes. Measurements from a large (slow rise rate) stope with high binder content CPB demonstrated a rapid departure from hydrostatic loading, resulting in relatively low barricade pressures. Conversely, data from a smaller (fast rise rate) stope with lower binder content CPB demonstrated that when cement hydration is retarded, high barricade pressures occur. These examples illustrate the relationship between CPB rise rate and the moderating effect of cement hydration on in situ pressures, which ultimately control barricade pressures. Once CPB gains shear strength, arching of pressures occurs. In situ pressures were reduced with proximity to stope walls and further, under stope access brows, demonstrating that barricade location influences barricade loads. The application of real-time pressure monitoring of pastefill barricades has been demonstrated as an important tool in optimizing operational backfilling efficiency.
In the coal-mining region of Central Appalachia, mountaintop-removal mining and coal-industry-related flooding, water contamination, and illness have led to the emergence of a grassroots, ...women-driven environmental justice movement. But the number of local activists is small relative to the affected population, and recruiting movement participants from within the region is an ongoing challenge. InFighting King Coal, Shannon Elizabeth Bell examines an understudied puzzle within social movement theory: why so few of the many people who suffer from industry-produced environmental hazards and pollution rise up to participate in social movements aimed at bringing about social justice and industry accountability. Using the coal-mining region of Central Appalachia as a case study, Bell investigates the challenges of micromobilization through in-depth interviews, participant observation, content analysis, geospatial viewshed analysis, and an eight-month "Photovoice" project -- an innovative means of studying, in real time, the social dynamics affecting activist involvement in the region. Although the Photovoice participants took striking photographs and wrote movingly about the environmental destruction caused by coal production, only a few became activists. Bell reveals the importance of local identities to the success or failure of local recruitment efforts in social movement struggles, ultimately arguing that, if the local identities of environmental justice movements are lost, the movements may also lose their power.
Safety and sustainability are becoming ever bigger challenges for the mining industry with the increasing depth of mining. It is of great significance to reduce the disaster risk of mining accidents, ...enhance the safety of mining operations, and improve the efficiency and sustainability of development of mineral resource. This book provides a platform to present new research and recent advances in the safety and sustainability of mining. More specifically, Mining Safety and Sustainability presents recent theoretical and experimental studies with a focus on: safety mining, green mining, sustainable development, risk management of mines, mining methods and technologies, damage monitoring and prediction. It will be further helpful to provide theoretical support and technical support for guiding the normative, green, safe and sustainable development of the mining industry.
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