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By Sandy Worden

Coal mining companies in Australia are managing the high-consequence risks across their operations more effectively by using an interactive online risk management system known as Riskgate Developed by the Minerals Industry Safety and Health Centre (MISHC) at the University of Queensland, Australia, Riskgate contains detailed information about 11 high-consequence risk areas (called topics in the system) for opencut and underground coal mines (Table 1). The existing topics are: fires; strata control for underground mining; ground control for opencut mining; tires; isolation; collisions; explosions and explosives; manual tasks; and trips, slips and falls. Every Riskgate topic is focused on coal industry activities (mining, processing, transport and storage). The scope includes mine sites, lease areas and mine infrastructure (mobile, fixed plant, field equipment, buildings, road and rail transport), and all aspects of the mine life cycle from design through to decommissioning. The topics uniformly recognize that a loss of control can result in injury or fatality, equipment damage, production loss, reputation loss and environmental damage. However, the priority focus for Riskgate is the safety of mine personnel.

Jul 1, 2013

By Konstantinos Komnitsas, Evangelos Petrakis, Emmanouil Varouchakis

During the modeling of grinding systems, population balance modeling (PBM) which considers a constant breakage rate has been widely used over the past years. However, in some cases, PBM exhibited some limitations, and time-dependent approaches have been developed. Recently, a non-linear framework which considers the traditional linear theory of the PBM as a partial case was introduced, thus allowing the estimation of product particle size distribution in relation to grinding time or the specific energy input to the mill. In the proposed model the simplified form of the fundamental batch grinding equation was transformed into the well-known Rosin–Rammler (RR) distribution. Besides, the adaptability and reliability of the prediction model are among others dependent upon the operating conditions of the mill and the adjustment of the RR distribution to the experimental data. In this study, a series of grinding tests were performed using marble as test material, and the adaptability of the non-linear model was investigated using three loads of single size media, i.e., 40, 25.4, and 12.7 mm. The results indicate that the proposed model enables a more accurate analysis of grinding, compared to PBM, for different operating conditions.

Jun 24, 2023

On Dec. 20, 2013, an 8-m (26.2-ft) diameter Robbins hybrid single shield/earth pressure balance tunnel boring machine (EPB TBM) was launched to bore the Grosvenor decline tunnel for Australia?s Anglo American coal mine. The machine was built using onsite first time assembly (OFTA) in order to fit within a tight project schedule. Assembly at the remote jobsite near Moranbah, Australia took about four-and-a-half months, and then the machine was walked down into a launch tunnel. Two decline tunnels, at grades of 1:6 and 1:8, will be used for mine access to new coal seams. The hybrid machine is tackling mixed ground conditions ranging from sand and clay to varying types of sedimentary hard rock up to 120 MPa UCS, as well as coal seams. Methane gas is expected to be present throughout the tunnel, so the machine has been designed as explosion-proof-compliant to ERZ-1. ?Grosvenor is the first underground coal mine in Queensland to use a TBM for drift construction,? said Glenn Tonkin, Grosvenor project director. ?We are proud to be pioneering this technology.? Only about 300 m (984 ft) of ground in each decline tunnel is expected to require EPB mode, while the rest of the tunnel will be bored in hard rock mode. Thus, the design was optimized toward hard rock excavation.

By Juan Camus

To understand why some companies excel in creating value, Jim Collins (2001) and a group of postgraduate business students engaged in a comprehensive, five-year research project. They examined 1,435 U.S. companies for more than 40 years, seeking those that made significant improvements in their financial performance over time. The distinctive pattern sought was: ?Fifteen-year cumulative stock returns at or below the general stock market, punctuated by a transition point, then cumulative returns at least three times the market over the next 15 years. ?The search identified 11 outperforming companies, all in different industries, that were called the ?good to great? companies. To contrast these companies with similar peers within the same industry, the search also selected a group of comparison companies that failed to make the leap from good to great. Collins then set out to examine the transition point. What distinguishing features did the good-to-great companies have that their industry counterparts did not? At the heart of the findings about these outstanding companies is what Collins refers to as the ?hedgehog concept? ? how to find the one big thing that the company must focus on. According to Collins, those who built the good-to-great companies were, to one degree or another, hedgehogs. Those who led the comparison companies tended to be foxes, never gaining the clarifying advantage of a hedgehog concept, being instead scattered, diffused and inconsistent. This insight is complemented by Peter Drucker (2004), an influential management guru, who asserts that the first question an effective executive should ask is: ?what needs to be done?? Asking this question and taking it seriously, he asserts, is crucial for managerial success; and that the answer almost always has more than one urgent task, but the effective leader only concentrates on one task. In this last respect, Drucker emphasizes: ?If they [executives] are among the sizeable minority who work best with a change of pace in the working day, they pick two tasks. I have never encountered an executive who is effective while tackling more than two tasks at a time.?

Jan 1, 2011

By Alexander N. Winchell

"Location. The copper mines of Michigan are all in the northern part of that state on the Keweenaw Peninsula, which extends from the (Michigan) mainland for about seventy miles northeasterly toward the middle of Lake Superior. The mines occur in a belt or zone occupying the central portion of the peninsula from end to end.. The most productive mines for many years past have been those located not far from the city of Houghton in' the central part of the zone, in a section extending about ten miles southwest of Houghton and fifteen miles northeast. The most important mines in order of location, from the northeast to south¬west, are the following: Mohawk, Ahmeek, Allouez, North Kearsarge, Wolverine, South Kearsarge, Centennial, Calumet. and Hecla, Osceola, Franklin, Quincy, Hancock, Isle Royale, Superior, Baltic, Trimountain, and Champion. The first three named are in Keweenaw county and all of the others are in Houghton county. Still farther to the southwest are the Lake, Mass, Adventure, Michigan, Victoria, and White Pine mines. These are in Ontonagon county.History. The exploitation of these copper mines extends back into prehistoric times. There is little evidence that the American Indians carried on mining operations in this region in the period shortly before the advent of white men, but there is abundant evidence that the ancestors of the Indians, •or some earlier inhabitants of the region, carried on primitive mining operations. For example, Mr. S. O. Knapp, Agent of the Minne¬sota Mining Company, in the winter of 1847-48, made the first discovery of prehistoric mining. This event is described as follows by Foster and Whitney :"

Jan 1, 1920

By D. A. Peacock

"INTRODUCTION Outer space technology and exploration have reached a tipping point so that mining and mineral processing in outer space is now a certainty and not a dream. Several competing companies, worldwide, are well on the way to building spaceships to land on the Moon and eventually mine the Moon and asteroids for volatiles, rare earth metals and Helium-3. The Google Lunar XPrize offers a $30 million prize1. China has recently landed a spacecraft on the Moon. The European Space Agency, with cooperation from the United States, has landed a spacecraft, Philae, on a comet. And, Mars One is planning a one-way trip to establish a settlement of humans on Mars. How and why are the Moon and asteroids and their resources of interest to private space industry and companies? Why are the Moon and asteroids viewed as a potential business venue? GEOLOGY OF THE MOON AND ASTEROIDS –WHY DO WE WANT TO MINE THERE? Space enterprises are actively working towards establishing and operating lunar and asteroid mining locations for resource extraction, resource processing, conversion to salable products, and distribution of the products and services in space and to Earth and beyond2. Forty-five years ago, the Apollo manned missions to the Moon returned rocks and regolith to Earth, which were studied and analyzed. What they found was that the Moon contains valuable minerals and resources. These minerals are largely due to meteor and asteroid impacts, which have, over eons, created this mineral rich regolith. These impacts have occurred on Earth as well, for billions of years, particularly early on in the history of the solar system. However, on Earth, wind, water, and vegetation have erased most of these impacts. On the Moon, in contrast, the only weathering is caused by subsequent impacts and the solar wind. The Moon regolith contains valuable rare earth minerals, platinum-group minerals (particularly where the Moon has been impacted by asteroids), volatiles (useful for processing and habitation), Helium-3 and titanium. Almost non-existent on earth, Helium-3 is abundant and accessible on the Moon and can be used in nuclear fusion power plants, producing much more energy than fission reactions and with much less radioactive waste. One of the main reasons Helium-3 is sought after as a fusion fuel is because there are no neutrons generated as a reaction product. Governments and private companies focus on mining of Helium-3 on the Moon as a basis for their economic models. Moon Express, one of the private companies who is planning on mining on the Moon, will recover moon rocks to fund its early operations25. Subsequently, it will recover Helium-3, platinum, and rare earth metals, as it engages in surface mining operations."

Jan 1, 2016

By David E. Thompson, Andrew F. McKown, Herbert H. Einstein, Amr S. Azzouz

INTRODUCTION Design of supports for underground chambers in rock has undergone considerable development. This becomes evident when comparing support dimensions of subway station caverns built in the U.S. over the past fifteen years. The Porter Square Station cavern, which is a part of the Massachusetts Bay Transportation Authority (MBTA) Red Line extension, is the latest in this series. It is approximately 168 m (550 ft) long, 21 m (70 ft) wide, and 14 m (45 ft) high, and has a permanent support of light steel ribs imbedded in a 0.4 m nominal (15 in) shotcrete lining. An extensive construction control instrumentation program made it possible to evaluate the performance of the cavern and its support. This evaluation, which is presented in this paper, was the objective of a research project sponsored by the Urban Mass Transportation Administration (UMTA) and jointly conducted by Haley and Aldrich, and MIT. The actually used design procedure was compared with other approaches, notably procedures based on Finite Element analyses and empirical rock mass classification methods. Support dimensions predicted with all these approaches were compared to the actual support and its performance.

Jan 1, 1983

By R. F. Balazik

By March 2001, shrinking global markets, reduced consumer spending and declines in domestic manufacturing and industrial output ended the longest economic expansion in US history and pushed the nation’s economy into its first recession in a decade. Aggravated by the terrorist attacks of Sept. 11, the recession led to large reductions in the domestic production of processed mineral materials. Some of the most significant production declines in the US metals industry were registered by aluminum, copper and steel producers. They faced strong foreign competition, higher energy costs and lower prices for their products. However, homebuilding and other domestic construction sectors — major users of nonmetallic mineral products such as cement, brick, glass and stone — remained strong enough to help raise the output of industrial mineral materials slightly above previous year levels. A strong US dollar continued to weaken the competitive stance of US metal and nonmetallic mineral materials companies alike against foreign producers in markets at home and abroad.

Jan 1, 2002

By M. P. Valoski

Mine fires and/or explosions continue to occur. While these are unusual events, they comprise emergency situations. Whenever one of these events occurs, the Mine Safety and Health Administration (MSHA) responds with specially trained teams, mine fire experts, sophisticated scientific instrumentation, and trained instrument operators. In order to analyze mine air samples on-site, because time is of the essence, MSHA has a Mobile Gas Laboratory. The laboratory, which is stored near Pittsburgh, is totally self-contained. Sending air samples to a laboratory would take too long. Mine fire experts need the results of the latest analyses as soon as they are finished. The mobile laboratory is housed in the box of a diesel truck. Benches line both sides of the laboratory. Gas chromatographs are mounted on the benches. There is sufficient bench space for multiple bench top gas chromatographs. These instruments and their controllers are shock and vibration isolated to protect them during transit. The mobile laboratory can operate using on board diesel generators or line power. An uninterrupted power supply (UPS) supplies power to the instruments while switching from generator to line power or visa versa. Therefore, analysis of samples can proceed without interruption if a power failure would occur. In the rear of the mobile laboratory are racks that hold compressed gas cylinders. These cylinders contain carrier gas and compressed air. An air compressor is housed under the laboratory to operate the gas chromatograph actuators. Within several hours after arriving at a mine the instruments have stabilized and have been calibrated. The mobile laboratory is ready to begin analyzing air samples. The mobile laboratory has proved itself at many mine fires and explosions since its purchase.

Jan 1, 2009

Underground mine designs typically try to avoid extraction beneath streams and rivers of any significant size, especially when the overburden rock thickness between the stream bed and the mine is thin. Potential issues with mining beneath streams include excessive groundwater inflow to the mine; weak ground (roof, floor, and pillar) conditions; horizontal stress effects; as well as stream loss and other potential adverse environmental effects. However, there are times when crossing beneath a stream or river is necessary to move into a new area of mineral reserve without creating additional mine access points from the ground surface. Often, stream crossings are completed without thorough assessment, potentially resulting in increased costs, decreased safety, and, in some cases, failure to advance the mine. Selection of the most favorable location(s) to cross the stream must account for numerous factors and the associated assessment often requires a multidisciplinary approach. Stream crossing investigations often require geological, hydrogeological, geotechnical, and geophysical expertise. Phases of stream crossing investigations include desktop evaluation of maps and aerial photography, stream bed observations, drilling, detailed rock core logging, downhole geophysical surveying, hydraulic conductivity testing (packer testing), geotechnical laboratory testing, assessment, and reporting. The deliverables from a stream crossing assessment typically include geological, geotechnical, and hydrogeological characterization of potential stream crossing locations; classification of favorable and unfavorable crossing locations; recommendations for entry design and pillar sizing; and recommendations for if, and how, to conduct pre-grouting activities. Examples of technical aspects of data collection and assessment are provided based on decades of industry experience conducting stream crossing assessments in various underground mining scenarios.

Jul 28, 2020

The Canadian mining industry is one of the strongest in the world. Not only does the country produce a sizable amount of minerals and metals, Canada plays host to hundreds of global mining companies, large and small. The country, for the most part, recognizes the importance of natural resource development, particularly mining, to its economic well being. Like any country, though, there are federal and provincial regulations on the books that the industry takes issue with. But there are also certain economic incentive programs in place to encourage exploration and mine investment. And, unlike the industry and the United States government, the Canadian government and mining industry appear to have a reasonable working relationship.

Jan 4, 2010

By LeRoy D. Loy

To facilitate effective land reclamation and comply with existing state regulations, surface coal mine operators have in recent years adopted new mining techniques and equipment utilization for steep-terrain mining. In contrast to direct spoiling with draglines or shovels, these new mining methods require some form of overburden haulage from the excavation face to the point of reclamation. Although current mining methodologies such as Block-Cut, Modified Block-Cut, and Mountaintop Removal with Head-of-Hollow Fills have proven effective in achieving reclamation objectives, some production problems have resulted from pit congestion and excessive equipment delays. Recognizing this problem, the United States Bureau of Mines contracted Skelly and Loy to design innovative mining concepts utilizing conveyor haulage in place of trucks, loaders, dozers and scrapers. Project objectives required definition of current bottlenecks and development of mining systems to: alleviate bottlenecks; increase production potential; facilitate additional resource recovery; enhance reclamation; reduce safety hazards; and improve mining economics. Successful completion of project goals within a four year program involves systematic implementation of the following separate work phases: 1) Develop Concepts for Block-Cut Mining Systems; 2) Determine the Economic and Technical Feasibility of Concepts; 3) Prepare Detailed Design and Specifications of Concepts; and 4) Prepare Specifications for Conducting Field Tests of the Most Promising Concepts. At the time of this publication, Phases 1 and 2 are finalized with Phase 3 efforts well underway.

Jan 1, 1977

By William Gleason

The Society for Mining Metallurgy and Exploration (SME) has a long and proud history of being the world?s leading resource for the dissemination for technical information regarding the fields of mining and mineral extraction and processing. That reputation was met, and maybe even exceeded, with the programming for the Society?s 2014 Annual Meeting in Salt Lake City, UT Feb. 23-26. The meeting drew more than 6,700 attendees to the three-day conference that featured more than 90 technical sessions with 670 presentations. These sessions covered the breadth of the mining and minerals industry, but it was the so-called ?softer issues? that were discussed in the keynote session that kicked off the meeting. The keynote session, ?Community Engagement: Building Partnerships for Mining,? brought together some of the leading voices from the mining industry, as well as some of the top voices from nongovernmental organizations (NGOs) that work in the mining sector. The common ground between the panelists was their dedication to working to ensure a social, economic and environmental balance in the development of mines. ?We wanted to bring these NGOs in to begin a dialogue to see how we can work together,? said SME President Jessica Kogel. ?This is a space that SME has not typically operated in, but one in which SME can bring a technical, scientific voice to the discussion. SME wants to play a leadership role in creating partnerships between the technical, social and economic areas that are crucial to the success of any mining project.? In today?s environment, finding mineral deposits and extracting the minerals in an economically viable manner is just one piece of an increasingly complex puzzle. Earning and maintaining a social license to operate requires careful consideration of local and global impacts. The industry often comes under intense scrutiny when a new project is proposed and, therefore, it must strive to meet the highest ethical and environmental standards. Success requires cooperation and collaboration between the industry, community and NGOs.

By James Wm. White

Today a large number of open pit mines use computer-based mine management systems to automatically assign haul trucks, track equipment, and manage information. Now advances in digital communications allow the use of these systems in underground operations. Underground mine management systems help maximize production by providing impressive gains in areas such as equipment and manpower utilization, draw point equalization in block caving operations, preventive maintenance, and safety. Current systems use allocated or "locked" train and LHD dispatching. While allocated dis-patching rarely optimizes open pit production, it offers an efficient mode of operation underground where options are more limited.

Jan 1, 1996

By Karoly (Charles) Kocsis, August Greth, Jon Fox

"It is the duty of the mine operator to ensure the mine environment is healthy and safe for the mine workers. For deep and hot underground mines, this requires maintaining adequate working temperatures by means of mitigating the heat load generated by strata, auto-compression, mining equipment, explosives, ground water and human metabolism. The heat load is best reduced by minimizing the amount of heat transferred to the mine air from these sources and through the use of efficient ventilation with effective cooling systems. The heat emitted by mining equipment and vehicles contributes a significant proportion to the combined heat load of an underground mine. This is especially a problem for diesel equipment due to the fact that besides heat, a large amount of water vapor is produced, which increases the humidity in the production workings. Diesel engines have proven advantageous in recent history due to their high power output and reliability. However, as mines continue to become more mechanized and deeper the climatic problems introduced by elevated heat generation will continue to rise. With that, the issue of heat generated by diesel equipment must be addressed.The economic alternative for diesel engine equipment fleets in underground mines is the electric engine. Technological advances in battery technology, increased mechanical output and improved reliability have made the electric engine significantly more competitive in comparison to diesel engines. Because electric engines do not utilize internal combustion, the heat produced by them is significantly less than the diesel engines. Battery-powered mining equipment likewise eliminate diesel particulate matter (DPM) produced by diesel engines. Utilizing battery electric equipment in underground mines provides many advantages, such as: (a) reduced heat load, (b) healthier and safer environment for the mine workers and (c) reduced mine operating costs due to lower ventilation requirements"

Jan 8, 2018

By C. A. Johnson, K. F. Unrug

The identification of the major subsidence areas in the Eastern Kentucky Coal Field has been made to distinguish the subsidence phenomena on the basis of geographical location. Further, this identification process is based upon selected critical geological, topographical, and mining features in the coal fields. The proposed identification of the regions is derived from a comparison of the subsidence potential in a particular area. The most likely severe subsidence areas are compared to those with the probable low subsidence severity. The combination of certain geological and mining parameters involved allows for the derivation of a classification of the subsidence potential.

Jan 1, 1986

By Allan E. Koski

Ceveland-Cliffs uses a specialized software package in mine planning at the Empire Mine, an iron ore mine it manages on Michigan’s Marquette Iron Range. The application puts together years of mining experience that began in the early 1960s on the eastern end of the Marquette Range. The Empire Mine is in its 38th year of production. It uses the software to model a complex and highly variable low-grade magnetite ore body, capturing the economics of mining and processing to the final product. With special attention given to geostatistical methods, the software is used for all geologic modeling, ore reserve estimation, ore control, pit design and short- and long-range planning.

Jan 1, 2000

By Swades Kumar Chaulya, Vikash Kumar, Sushma Kumari, Naresh Kumar, Girendra Mohan Prasad, Monika Choudhary

During harsh weather conditions, the presence of fog, dust in the environment degrades the image’s quality, which affects the visibility of drivers of heavy earth-moving machinery in opencast mines. Due to low visibility, mining operations cannot be carried out as drivers are easily prone to accidents. This paper proposes a technique that includes developing a vision enhancement system called perceptive driving assistant system for increasing visibility of real-time video of the road in front of the vehicle for operators of heavy earth-moving machinery at opencast mines during harsh weather conditions to overcome the problem. The system consists of high-quality Internet Protocol cameras and thermal cameras for real-time image processing and other well-defined devices, which is quite capable of enhancing the visibility of the image, outlining edges of the road, and detecting obstacles present on the path of operators for smooth driving and reducing threat of accidents. A high-speed graphical processing unit has been used for quality-performance parallel computing, which is well suited for real-time operations to empower fast real-time operations. The calculated frame per second (fps) of image enhancement, object detection, and edge detection is 17.91, 15.91, and 25.09 fps, respectively. The actual frame rate is 26.07 fps, and after applying the algorithm, the final frame rate is 19.65 fps. The calculated accuracy of the object detection model is 81.23%. Field trials indicate that the developed system has performed adequately during foggy weather.

Sep 21, 2022

By Sean Masse

New Gold?s New Afton Mine, located 8 km (5 miles) west of Kamloops, British Columbia, is a 4.5-Mt/a (5-million stpy) block cave mine, making it the highest tonnage underground hard rock mine in Canada. The reserve is estimated at 52.5 Mt (55.9 million st) with grades of 0.65 g/t (0.02 oz/st) gold and 0.93 percent copper (2012). Commercial production was achieved in July 2012 and nameplate production was achieved ahead of schedule in September 2012, with the cave breaching to surface in 2013. The mill has a SAG and a ball mill with a froth flotation circuit.

Jan 1, 2014

By G. M. Bernard

The Andacollo gold mine is located near the small town of Andacollo, Chile (population 14,000) in the fourth region. It is approximately 35 miles by paved road from the coastal city of La Serena, and Santiago lies about 300 miles to the south (see map.) Site elevation varies between 3300 feet and 4200 feet. The climate at the site is moderate but arid, with an average annual rainfall of only five inches. Because there is little rain, and the temperature varies only a few degrees (57"F to 75°F); there are no freezing, solution dilution, or pad saturation problems. The climatic conditions are ideal for heap leaching.

Jan 1, 1996