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By Cristina da Paixão Araujo

O planejamento de lavra de curto prazo tipicamente confia em amostras obtidas de furos de desmonte em uma operação de lavra a céu aberto. Essas amostras podem conter grande erro de amostragem. O objetivo deste artigo é avaliar o impacto do erro de amostragem na recuperação de lavra. Para comparação, foi utilizado banco de dados Walker Lake exaustivo considerado como a distribuição real dos dados. A metodologia consiste na obtenção de amostras a partir dos dados exaustivo, em um espaçamento regular de 5x5 m. Em seguida, o erro de amostragem foi adicionado às amostras. Posteriormente, as amostras foram utilizados para estimar os blocos e classifica-los como minério ou estéril. Quatro cenários com amostras com 0%, 10%, 20% e 30% de erro relativo. A recuperação de lavra de cada cenário é comparada com a real distribuição dos dados. Além disso, o erro de classificação do bloco é avaliado para os quatro casos. Os resultados mostram que problemas na amostragem e no protocolo de preparação de amostras pobres afetam a curva teor tonelagem e a classificação dos blocos em minério e estéril.

Aug 8, 2018

By Germán Mallén

Como parte de los estudios línea base realizados por MWH Perú S.A. para el proyecto aurífero Chucapaca de las Canteras del Hallazgo en el distrito de Ichuña de la región Moquegua, Perú, se investigó el origen de boro, alta salinidad y otros componentes que perjudican la aptitud de los ríos Ichuña y Tambo para irrigación y otros usos. En este sentido, se encontró que la calidad de agua es perjudicada principalmente por altas concentraciones de sodio, entre otros, precipitándose como hidróxidos de estos metales debido al pH neutro en el río. En ese sentido, el presente texto describe la relación de este impacto químico con los manantiales entre el Cerro Chucapaca y el cañón del Río Ichuña/ Alto Tambo, ubicados al Norte de Moquegua, donde presentan la característica distribución de diferentes tipos de aguas volcanogénicas sobre un sistema de convección hidrotermal de agua meteórica profunda reciclada, calentada y movida por una cámara magmática andesítica que aporta calor y gases.

Sep 21, 2013

By Juan Anes, Omar Godínez, Adrián Tolentino, Mario Franco

Como aplicación práctica de las herramientas hidrodinámicas de flotación desarrolladas por Flottec, McGill y otros investigadores, el objetivo del estudio fue crear, para Minera Fresnillo, una herramienta preliminar de control de procesos, a nivel de la primera celda de la flotación primaria del circuito de plomo, con el fin de expandirla luego a toda la planta. El trabajo determinó ecuaciones matemáticas que describen las relaciones entre las variables de proceso e hidrodinámicas para aumentar la recuperación de plata mientras que disminuye la cantidad de insoluble al concentrado. Se desarrolló usando diseño de experimentos con tres variables (nivel de espuma, adición de espumante en ppm, y flujo de aire en cm/s) para observar los cambios en la recuperación de plata y plomo.

Sep 20, 2019

By David Ramírez

"Dentro del proceso de optimizar la fragmentación del mineral por voladura, el principal objetivo es determinar el impacto que tendría la incrementación de las partículas medias y finas sobre la extracción de cobre en elmineral ROM, (Run of Mine), que actualmente constituye una de las fuentes de producción por lixiviación en la Sociedad Minera Cerro Verde. En ese sentido, el presente trabajo describe la cantidad de cobre que aporta el mineral ROM a través de su optimización en el proceso, así como el impacto económico que tendría a futuro. Para ello, se utilizan los resultados de las pruebas para los módulos experimentales 12 y 13 desarrolladas entre 1998 y 2000, y la validación preliminar del sistema de análisis granulométrico por fotos (Split Desktop) desarrollado en julio del 2002 para así otorgar validez a los resultados fotográficos de granulometría reportados para las diferentes pruebas de voladura. "

Jul 31, 2003

By Ronald Ticona, Jair Alarcón

Generalmente, la operación de perforación y voladura se gestiona de forma independiente a los resultados de la planta de procesamiento. Por lo tanto, la segmentación técnica para determinar los diseños de perforación y voladura del mineral no incluye las propiedades de la roca de la planta de procesamiento, como el Bond Work Index, Axb, Drop Weight Index u otros. El año 2021, en la operación de una mina de cobre del Perú, de acuerdo a su plan de minero tendría una dureza de molienda SAG significativamente mayor, lo que impactaría directamente en la producción de concentrados de cobre. Se volvió necesaria la búsqueda una estrategia integrada entre mina a planta para mantener los niveles de producción.

Sep 30, 2022

By Alexi Delgado, Carlos López

Los pasivos ambientales mineros (PAM en sus siglas en Perú), constituyen uno de los mayores problemas en el Perú, ya que son causa de conflictos sociales por el impacto que generan en el medio ambiente, especialmente en la calidad del agua, la metodología escogida para realizar la investigación fue Grey Clustering la cual brinda una alternativa para evaluar la calidad de agua de manera integral considerando la incertidumbre dentro del análisis, específicamente, se utilizó como mecanismo de evaluación para determinar la calidad del agua de la cuenca del río Llaucano la función de peso de blanqueamiento triangular del punto central, mejor conocida como CTWF (center-point triangular whitenization weight functions), que es un enfoque del agrupamiento gris.

Sep 29, 2023

By Kássio Nogueira Cançado

O objetivo desse trabalho é analisar a eficiência de um forno de aquecimento de barras quantificando o impacto de paradas não programadas na linha de produção. Para isso foram realizados 3 balanços energéticos durante um período de 7 horas. O primeiro balanço foi realizado em um intervalo com registro de paradas, o segundo no período subsequente sem ocorrência de paradas e o terceiro englobando o período total produção analisado (balanço 1 + balanço 2). Tomando-se como referência o resultado do balanço energético sem ocorrência de paradas temos duas situações: a eficiência do forno no período com ocorrência de paradas apresentou uma queda de 27% em relação ao período sem paradas, em relação ao período total de produção a redução foi de 20%. Esses resultados permitiram fazer a projeção, que se a produção ocorresse sem paradas, o potencial de redução seria aproximadamente 15% no tempo total de produção com uma redução de aproximadamente 23% no consumo de combustível. Portanto, destaca-se a importância de um plano de manutenção eficiente, com o objetivo de minimizar o tempo de linha de produção parada e o consumo de combustível, além de aumentar à qualidade aquecimento a vida útil do equipamento térmico.

Oct 30, 2017

By Yohel Olortegui, Rolando Alvarado, Julio Sagua, José Lima

La planificación estratégica de una operación minera debe estar en constante evolución para hacer frente a escenarios cambiantes, y en ocasiones atípicos, como variaciones agresivas en el precio de los metales, tecnologías emergentes, modificaciones a estándares y normas legales para desarrollar el negocio minero, entre otras. Es entonces necesario implementar innovaciones revolucionarias, en lugar de solo mejoras constantes (Hammer, 2004). Lograr esta mencionada innovación operacional genera impactos de mayor magnitud en la cultura operativa, trayendo consigo la reducción de exposición a peligros, incremento en uso de energías limpias y reducción de huella de carbono, cambio en la estrategia de operación, reducción de costos operativos.

Sep 30, 2022

By Luiz Afonso Andrade, Pablo Amâncio de Freitas, Ana Patrícia Andrade Jaccard, Eduardo Cezar Ribeiro, Ana Christina Pitard Lima, Rodrigo Ribeiro de Souza

A análise dos carvões em mistura é de suma importância para redução dos custos e controle de qualidade de uma coqueria, esse trabalho trata da influência da cominuição comum de carvões de diferentes ranks, assim como suas implicações no processo de amostragem e consequentes desvios nas análises. O processo de produção da mistura de carvões na Ternium Brasil possuía um desvio não rastreado entre matéria volátil resultante da amostragem automática da mistura de carvões e a matéria volátil esperada pelo resultado da média ponderada dos carvões individuais no recebimento, para tal foram estudadas todas as etapas do processo de produção da mistura de carvões desde a variação dos carvões em pilha, escoamento em silos e na etapa anterior e posterior a britagem. Os dados foram comparados e foi feito um plano de ação para redução do desvio.

Oct 1, 2019

By Frederick B. Henderson

The US Environmental Protection Agency (EPA) has tried many regional and laboratory efforts to develop measurement and monitoring techniques using environmental remote sensing technologies. In 1997, the agency established the Advanced Measurement Initiative (AMI): This is a eadquarters-level program, operating under the auspices of the EPA Office of Research and Development. The program is one result of the April 30,1996 White House Conference on Advanced Monitoring of the Environment. The EPA was encouraged to work with other federal agencies to leverage its remote sensing capabilities and use them to improve the efficiency, cost-effectiveness and flexibility of environmental measurement and monitoring for regulatory compliance and reinvention. During the fall of 1996, the EPA and the Department of Energy developed an interagency effort to broaden the use of governmental technologies for environmental measurement and monitoring. In addition, the EPA and the National Aeronautics and Space Administration (NASA) conducted joint workshops on the use of NASA remote sensing and other technologies for water quality and pollution applications. In the meantime, the EPA proceeded with an industry-proposed workshop to explore ways to cooperatively examine new research and to develop commercial remote sensing systems. It also examined how these systems might become accepted by the EPA in the regulatory and compliance processes. In particular, industry was interested in where new remote sensing capabilities might fit in with EPA's efforts at regulatory reinvention. Historically, the mining and petroleum industries have been reluctant to experiment with or use environmental remote sensing. They were concerned with the unknown liability from potential discovery of previously unknown environmental problems. Moreover, resource industries have been reluctant to use remote sensing for environmental applications where the EPA did not accept such data or information as part of the compliance process. Acceptance by the EPA of these advanced measurement and monitoring technologies (AMMT) will be a major reason for industry's increasedd use of remote sensing in environmental "applications for regulatory compliance. In July 1997, the EPA Office of Research and Development hosted at the Colorado School of Mines a stakeholders workshop on the AMI program and industry-government collaboration. The workshop's aim was to demonstrate the usefulness of AMMT technologies for environmental applications. Stakeholders included the mining and petroleum industries; environmental services companies; state environmental agencies and local governments; remote-sensing, value-added companies and data suppliers. The workshop used specific technologies and applications as a way to develop collaborative demonstration projects for several AMMT technologies covering different environmental problems. The workshop focused on the use of highly sensitive hyperspectral (very narrow spectral bands), geographic information systems and surface mapping to identify active acid-producing mine dumps and wastes from benign wastes at Leadville, CO. NASA's advance infrared imaging spectrometer (AVIRIS) was the instrument used. It was developed at California Technology's Jet Propulsion Laboratory. The EPA, the US Bureau of Land Managment (BLM), the US Geological Survey and several environmental service contractors sponsored the overflight and data evaluation. The AVIRIS study demonstrated reliability (95% correct surface mineral identification) and cost-effectiveness of this technology to accurately map and discriminate active acid-producing mine wastes from benign wastes. It could also predict which streams would be effected by acid and toxic mineral drainage. The BLM'said that the AVIRIS overflight could save it $500,000 a year in surface sampling costs at Leadville. The AMI workshop further outlined five 1997 funded AMI projects of potential interest to the mining industry. They were: ? Mine waste characterization using remote sensing methodologies at Asarco's Ray Mine in Arizona. ? Predictive emissions development and testing in

Jan 1, 1997

By Jeffrey W. Lin, Larry B. Weston, Jonathan D. Abbott, Jordan L. Arthur

Hydrocarbon fuel oils are one of the main components of ammonium nitrate-based explosives, including ANFO (Ammonium Nitrate-Fuel Oil) and emulsions. While a wide variety of fuels can, and have, been used in the manufacture of ANFO and emulsion products, No. 2 diesel, particularly dyed, off-road diesel, is widely used due to its ready availability and use in fueling mining equipment. However, a number of alternatives to standard diesel have been introduced over recent years, namely, biofuels, ‘high-performance’ diesels, and renewable diesels. The pressure to adopt these alternative fuels come from a variety of sources, such as initiatives to reduce carbon footprints, increased lifetime of equipment, and cost-advantages from tax credits. While these factors may provide a very real benefit to the mine site, a consideration that is often missed is how the use of these fuels can impact the formulation and characteristics of the ammonium nitrate-based explosives. Herein will be presented a discussion of these alternative fuels from a chemical perspective as well as the results of several studies focused on how the inclusion of various alternative diesels influences the production and performance of ammonium nitrate explosives. ANFO and emulsion were manufactured using representative fuel sources and studying in terms of the manufacturing parameters, shelf-life, interaction with other chemicals using in mining explosives. Detonation data was then collected for these products and compared to the behavior of products made with standard diesel fuels.

Jan 21, 2025

By L. Micale

In May of 1986, the Arizona Legislature passed comprehensive environ-mental legislation called the Environmental Quality Act (the Act). The Act focuses on ground water protection and addresses drinking water quality, aquifer protection standards, requirements to apply technology to reduce discharges, and a state Superfund program.

Jan 1, 1988

By Casandra Gamez Gonzales, Angelina Anani

Copper, the newest addition to the critical mineral list, is an essential metal whose electrical and heat conductive properties label it as a vital mineral for the creation of renewable energy sources and the reduction of Greenhouse Gases (GHGs). However, despite copper’s leading role in the transition to sustainable energy and mining practices, the mining industry has faced various battles in the extraction of this valuable material. These challenges are based on mining’s negative reputation and extensive impact on the environment, nearby communities, and human rights. To ensure the survival of mining in the future and achieve mineral demands, an emerging topic that has initiated the revolution of the traditional sector into a more environment- friendly and transparent industry, is Environmental, Social, and corporate Governance (ESG). ESG has motivated companies to seek growth opportunities and standardize risk accountability and transparency based on its collective framework that creates, modifies, and implements local, national, and international standards. These standards focus on improving environmental, social, and governance issues faced by companies and their projects. ESG has served as a guideline that investors utilize to assess companies and promote sustainability, responsibility, and disclosure to create positive and balanced relationships with stakeholders and the environment. Nonetheless, concerns have been rising which state that ESG is negatively impacting the mining industry by targeting what fuels the industry and world: ore deposits and their resources. Therefore, this research focused on answering the following research questions: what are the impacts of ESG on the copper supply chain and how will stricter ESG standards affect future copper production?

Feb 1, 2024

By Michael S. Kucker, Stuart Warren, Robert A. Robinson, Michael J. Lehnen, David McAllister

Geotechnical conditions exposed by the phased exploration programs have had a major impact on the selection of excavation and support methods, dewatering requirements, size of openings, vertical alignment, and estimated cost of construction for the Beacon Hill Tunnel and Station section of the “Link” Light Rail. Beacon Hill is comprised of a very complex glacial geology, including numerous slickensided fractures, injected sand dikes, and multiple perched groundwater levels as revealed by a phased boring program and exposed in a test shaft. The Geotechnical Baseline Report (GBR) presents this complex geology along with a “tool box” of alternative additional support systems to accommodate the varying ground conditions during construction of the station excavation. Additional explorations will also be accomplished during construction to further refine the geotechnical interpretations and provide an opportunity to use pro-active ground improvement techniques to optimize the station excavation and support requirements.

Jan 1, 2005

By Ebrahim Farrokh

Ghomroud water conveyance tunnel project is under construction using shield Tunnel Boring Machines (TBM) for a total length in excess of 50 km. Phase 1 of the project included 36 km of tunnel divided into four lots (1, 2, 3, and 4) of nine km each. Lots 3 and 4 of this tunnel for a total length of 18 km were combined into one award and have been constructed using a double shield (DS) TBM or one path system. Extreme ground convergence in some sections of the tunnel has stalled TBM performance in early reaches, due to face collapse and shield jammings. This paper presents the latest update on the tunnel progress and impact of ground convergence on machine performance based on the information obtained from field observations. Also, the method and results of tunnel convergence measurements were studied in conjunction with geological parameters and an attempt was made to correlate TBM operational parameters and ground convergence. The result of the analysis indicates a good correlation between machine?s operational parameter and tunnel convergence and can be used as an indicator of the potential for high rates of convergence. An early warning on ground convergence is essential for taking precautionary measures to avoid TBM jamming and related long delays and costs.

By Vanessa Viterbo, Lia Walker, Hassan Khaniani, Vitor Viterbo

Fatigue is a major contributor to haul-truck incidents in mining, with up to 65% of fatigue-related events associated with operator drowsiness or microsleep episodes, Williamson et al. (2011) and Caterpillar (2007). This study examines whether operator fatigue produces measurable and repeatable signatures in haul-truck telemetry. Eight confirmed fatigue-related disengagement events were analyzed using 20-minute telemetry windows centered around the incident. Statistical descriptors, Z-score normalization, first- and second-order derivatives, sliding-window variability, and cross-signal correlations were extracted from engine speed, throttle position, fuel rate, ground speed, and brake indicators. A logistic regression classifier was trained and evaluated using leave-one-event-out cross-validation. The model achieved a receiver operating characteristic (ROC) area under the curve (AUC) scores of 0.75–0.79, demonstrating consistent discriminative capability. A characteristic shutdown sequence characterized by sudden throttle collapse, fuel-rate decay, RPM reduction, and unbraked coasting was observed across all events, indicating operator disengagement rather than mechanical malfunction. Earlywarning indicators appeared 90–500 seconds before shutdown in the events analyzed, suggesting practical potential for real-time fatigue prediction. These findings provide initial evidence that telemetry-based fatigue detection is feasible and could enhance safety in mining operations.

Feb 22, 2026

By R. V. Ramani

Demands on available lands will continue to increase due to the projected increase in population and industrial expansion. Though there is an upper limit on the available lands, the multi-use nature of the lands will make it possible to meet these demands. However, this will not happen without adequate planning. Land uses can be broadly categorized as non-renewable and renewable. Lands with mineable resources can be dedicated at some point in time to the extraction of resources. Such a dedication, however long-term, is only temporary because of the non-renewable nature of the mineable resources. Implied here is that the land will be available before and after mining for other uses. Planning for such lands must have the objective that, as far as practicable, no non-renewable uses are pre-empted and no renewable uses are permanently destroyed. The primary aspects of this planning process will be addressed in this paper, These aspects include a discussion of planning responsibility, data needs and availability, the integration of mine planning and post-mining land use planning and a long-term plan for resource conservation and utilization. Minerals, together with agriculture and forestry products, are the primary sources of wealth. Therefore, to avoid land development that may pre-empt future mineral resource utilization, the local planning groups must be aware of the mineralization and mining potential. Much work needs to be done to identify and characterize the mineral resources. Even more work is needed in land use planning for lands with mineral deposits.

Jan 1, 1982

By David Bartsch

The Ohio Valley Coal Company (Ohio Valley) has operated the Powhatan No. 6 Mine in Belmont County, Ohio since 1972. Ohio University owns a 455-acre research farm over a portion of the Ohio Valley reserve containing 51 acres of old-growth forest known as Dysart Woods. In 1988, when Ohio Valley applied for a new mining area for its first longwall located several miles away from Dysart Woods, Ohio University claimed that mining at that distance would lower the regional water table and kill the old trees. In response, Ohio Valley began to study potential impacts from longwall mining on hydrology, soil moisture, and tree growth. Early studies examined the impacts of longwall mining on hydrology, soil moisture, and tree growth directly over mined areas compared to woodlots that were not undermined. A subsequent study examined tree-ring growth for a five-year period before and after longwall mining for several woodlots, some directly over panels and others at distances of up to 2000 ft away. No significant differences in growth rate associated with longwall mining were observed. New research was begun that compared longwall-mining impacts on groundwater hydrology, available soil moisture, and tree growth in two stands of mature trees located near Dysart Woods in order to confirm the earlier results. Using a test technique known as "Before-and-After-Controlled-Impact-Pairs," data was collected from one woodlot (test) that was undermined and from another (control) that was not undermined. Data collection began several years prior to longwall mining and has continued for several years after mining. The data for the test site shows that although the shallow and deep groundwater levels were affected by longwall mining, the soil moisture, vigor rating, or the growth rate of trees did not decline significantly compared to the control site where there were hydrologic impacts. The study shows that there are no known significant impacts to trees from longwall mining. The results of these studies were used by Ohio Valley to obtain State approval to longwall to within 300 ft of Dysart Woods

Jan 1, 2005

By Gavin Yuill, Kameron Ray

"The impact on vibration model accuracy by input data that is inaccurate was previously unknown, butthought to introduce significant error. This paper explores the impact of accuracy of different GPSreceivers, bulk truck density fluctuations, and charge weight location convention on the accuracy of the final vibration model output. GPS accuracy is compared between a professional Differential GPS, a “prosumer” GPS unit and a standard consumer GPS chip commonly found in cell phones. Bulk truck density fluctuations are compared from the density given by the operator and the actual cup density measured in the field. Charge weight locations explored are from the bottom of the blast hole, center of the powder column, and collar of the hole. The findings show that the weakest link in vibration model creation is actually low seismograph accuracy standards. Errors introduced from such are generally greater than those introduced from other sources."

Jan 1, 2017

By J. H. Desautels

The modern coal mining industry is subject to a vast array of regulations affecting virtually all aspects of its operations. Probably the most significant over-sight role involves the Office of Surface Mining Reclamation and Enforcement (OSH) established by the Surface Mining Control and Reclamation Act, or SHCRA.1 Although complying and coping with SHCRA can be difficult for coal operators, this complex regulatory process has helped insulate the industry from ongoing efforts to extend regulation under the Resource Conservation and Recovery Act, or RCRA, 2 to aspects of the mining industry in general. The Environ-mental Protection Agency (EPA) has struggled with regulation of mining wastes under RCRA since the mid-1970's, but RCRA itself places most coal mining wastes firmly under the control of OSH and SHCRA. Despite the general exemption from RCRA regulation for waste materials that result from extraction and processing of coal itself, there may be circumstances under which coal mining operators could find themselves subject to regulation under RCRA or a number of other statutes administered by EPA. This paper will review briefly the history of mine waste regulation under RCRA, as well as touch on the policy decisions that led to the exemptions from RCRA regulation. The paper will summarize coal waste requirements under SHCRA, and also will review what operations at coal mines need to be controlled, in order to avoid potential liability under RCRA. In addition, it will mention requirements under other federal laws, including CERCLA, or the "Superfund" law,3 and describe how they may impose restrictions or liability on coal operations for waste or other materials commonly found at surface and underground coal mines.

Jan 1, 1993