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By H. Kinilakodi

In 2008, the authors developed a methodology for identifying underground coal mines at high risk for major-hazard events. It focused on major hazard-related violations of safety standards associated with high-risk conditions. Later, using a sample of 103 mines with 2008 and 2009 data, injury measures and U.S. Mine Safety and Health Administration (MSHA) citation data were combined into a safe performance index (SPI). The SPI was used to assess the relative safety-related risk of mines, including by mine-size category. In this paper, comparisons are made of SPI-associated, normalized safety performance measures across mine-size categories, with emphasis on small-mine safety performance as compared to large and medium-sized mines. Mining Engineering, 2011, Vol. 63, No. 10, pp. 73-77. Official publication of the Society for Mining, Metallurgy and Exploration, Inc.

Jan 1, 2011

By B. Whisner, A. Smith, J. Carr

"Electromagnetic based proximity detection systems (PDSs) are utilized on mining machinery to protect workers from being pinned or struck. These systems generate magnetic fields covering the space around a machine, and a miner-wearable component (MWC) detects the field. The PDS determines the distance of miners relative to the machine based on the detected magnetic flux density in the magnetic field. This information is used to establish warning and shutdown zones around the machine. Maintaining a stable magnetic field is essential for system accuracy. However, components used to generate magnetic fields can be influenced by temperature changes. Depending on ventilation conditions and seasonal alternation, a PDS can be subject to significant temperature fluctuation. To better understand and quantify this phenomenon, researchers from the National Institute for Occupational Safety and Health (NIOSH) developed an experimental apparatus to study the influence of temperature on magnetic field generator circuits used in PDSs. Results from the study show that the electric current through a generator can be influenced by both ambient and internal temperatures, modifying the magnetic field that is produced. These findings show that temperature can significantly influence the ability of PDSs, used in underground coal mines, to accurately determine a worker’s position in relation to mining machine. INTRODUCTION Electromagnetic based proximity detection systems have been developed to reduce machine-related accidents in underground coal mines. The first proximity detection systems installed in underground coal mines were developed for continuous mining machines (CMMs). There are five of such proximity detection systems that are approved for use in U.S. mines by the Mine Safety and Health Administration (MSHA) (Mine Safety and Health Administration, 2013; Mine Safety and Health Administration, 2015). There are several basic components that interact within an electromagnetic proximity detection system (PDS). A PDS includes two main elements: a set of generators to create magnetic fields around a CMM and a set of magnetic probes to detect the fields. These systems can determine if a miner is located at a safe distance from the machine based on the detected magnetic flux density. Stability of the magnetic fields is essential for system accuracy."

Jan 1, 2018

By David Mast, Irwan Halim, Seung Han Kim

Fermilab is constructing a large underground cavern in Limestone to house scientific equipment. The cavern will have a complex L-shaped geometry and about 215-foot depth with relatively shallow rock cover, with service/egress shafts accesses into the cavern. Three-dimensional analytical models were developed to study the ground behavior and support performance. Multiple rock constitutive and failure models were evaluated. The models were significantly impacted by the high lateral in-situ earth pressure at the site. This paper will describe the design approaches that were taken to optimize the cavern arch geometry to allow safe construction in shallow rock, and permanent support requirements.

Jun 13, 2021

By Charles W. Merrill

The price records of 7 representative mineral commodities for the 68-year period 1890 through 1957 have been compiled and analyzed for significant trends. When reduced to real prices in terms of dollars of constant purchasing power or to the purchasing power of industrial wages at average rates, a substantial overall fall in prices is revealed. This downtrend contradicts the widely held concept that, heavy drafts on a mineral resource must lead to scarcity, reflected in rising prices. Three metals (aluminum, copper, and pig iron), two fuels (bituminous coal and petroleum)', and two nonmetals (sulfur and cement) have been chosen because of their preeminence in their respective categories, their significance in an industrial economy, and the ready availability of their price records. It might be added that these seven commodities. were selected before any price figures were compiled, none was selected or rejected to substantiate any preconceived notions as to price trends, The overall importance of the seven is demonstrated by the fact that, taken together, they composed over three-fourths of the value of all minerals produced in the United States in 1957. The first step in the analysis was to reduce the price records to a basis for significant comparisons, Two such comparisons have been made: (1) The quantities of each of the commodities that could have been purchased for an average hour's wage in each year; and (2) the unit price of each commodity through hhe years in terms of deflated dollars. These data are set forth in the accompanying table and two charts.

Jan 1, 1959

By William C. Ellis

Underground water is part of a continuing hydrologic cycle, which involves all elements of water occurrence. All groundwater of economic importance is in process of movement through a porous rock stratum from a place of intake or recharge to a place of disposal. Groundwater moves and is contained in fractures in the rock and/or in intergranular spaces of porous formations. Where there have been no water developments by man, groundwater is in a state of approximate equilibrium and the forces of replenishment and discharge are in balance. Thus, groundwater, unlike other mineral resources, is constantly being replenished in most areas at a rate which is measurable and which is important in the planning of its utilization. As illustrated by Figure 1, replenishment of groundwater supplies results from the direct penetration of rainfall through the soil to the water table, by seepage from surface streams or ponds, and/or by subsurface movement from an adjacent groundwater body. Under natural discharge conditions, water is commonly consumed by transpiration of trees and other types of vegetation, by flows from springs, by evaporation from shallow depths below the surface, and seepage into streams that traverse the area.

Jan 1, 1964

By X. Meng

A kinetic model for batch leaching of various metals with different lixiviants has been developed. Overall material balances for reactants and products at the solid/liquid interface were formulated with various types of heterogeneous reactions in place at the interface. The solutions to these mass balances have been identified analytically as well as numerically using a Runge-Kutta method. Applications of these numerical solutions to various leaching systems using the rotating disc or powders have been discussed. Examples of the metal dissolution systems considered in this study include cobalt, nickel, copper and gold in acid, cyanide or ammoniacal solutions.

Jan 1, 1994

By K. J. Shoop

Coal-fired power plants in the U. S. produce approximately 20 million metric tons of Hue-gas desulfurization sludge every year. The sludge mainly consists of calcium sulfite and calcium sulfate. This can be converted to synthetic gypsum, which in principle could be a marketable commodity. However, many Hue-gas scrubbers produce sludges that do not meet the quality requirements of the gypsum industry, and so their sludges must be landfilled as a waste. If a suitable method can be developed for removing certain objectionable impurities from the sludge, it will then be possible to market the material instead of landfilling it. A sludge from a natural-oxidation scrubber was characterized, and the main contaminant was found to be calcium carbonate from unreacted limestone. Based on the particle size and the characteristics of the material, froth flotation was considered as a method for purifying the material. Since no flotation studies have ever been carried out to separate calcium carbonate particles from calcium sulfite or calcium sulfate particles, it was first necessary to select a suitable collecting reagent. Based on Zeta-potential studies, the most suitable reagent was found to be an octadecylamine-octadecylguanidine complex. Results are presented for flotation of calcium carbonate from scrubber sludge using this reagent, in a reverse-flotation process. The best results were obtained when the sludge was first pre-cleaned using a water-only cyclone to remove unfloatable coarse limestone, followed by froth flotation to remove fine limestone.

Jan 1, 1998

By V. Svalbonas, S. M. Jones, A. Boughey

In June 1998, the world's largest grinding mill, the 40 ft (12.2 m) diameter 20 MW Cadia gearless SAG mill, was commissioned. This was a leap of over40% above the largest operating SAG mill. A significant saving in capital cost gave the incentive necessary for a single mill line at Cadia, resulting in the selection of the 40 ft (12.2 m) diameter mill. Now, after 18 months of operation, this paper will review the significant items involved in the development, design, manufacture, installation, and operation of this mill.

Jan 1, 2000

By F. L. Pierson

Since the discovery of 'potash in the Carlsbad area in 1926 and the start of mining operations in 1931, "first mining," operations have been carried on. This is a room and pillar system in which approximately 62% of the total ore is removed. Or the basis of ore reserves and rates of extraction, the life of the mine in the early; days was estimated to be well over 50 years, however, even with an increase by additional ore reserves, it became increasingly apparent that the life of the mine was being shortened considerably by increased production. Further cause for the shortening of mine life was due to the exceptionally weak back over the northeast quadrant of the main orebody which had .caved in on first mining up to a height of 8 feet. Thus, in 1953 the decision was' made to begin pillar pulling, also called, second mining or final mining, and in December of 1953 this program was started after much discussion.

Jan 1, 1965

By J. J. Fallon

The subject is "Mergers, Acquisitions and Divestitures in Industrial Minerals, but my remarks could also be applied to new product development, resource development and other new business development activities. At the kernel of the subject is due diligence in major decision-making, that is, where major money amounts and a large corporate commitment are at stake. The "due diligence" means how carefully we do our homework before making the decision. The homework or feasibility study addresses different parts of the decision. In the industrial minerals business the study seeks to uncover the pros and cons in: o The mineral reserves, quantity, quality, mineability, access, etc. o The environmental impact of mining, processing and transporting. o The economics of operations. o Financial aspects o Legal aspects o Many other aspects o And -oh yes! the marketing aspects.

Jan 1, 1990

By David R. Delling

Tenneco is a large, diversified, energy-based company which has grown rapidly during its forty year life. We're the youngest corporation among Fortune's top 20 companies. Tenneco Minerals Company is the division of the Corporation responsible for nonfuel minerals exploration, development and operations. Tenneco Minerals Company is headquartered in Lakewood, Colorado. Exploration offices are in Colorado, Nevada, Alaska, and Perth, Australia. We currently operate two gold mines in Nevada and a large underground trona mine and soda ash processing plant in Wyoming. The latter has a capacity of 907 000 tonnes per year of soda ash and is the subject of my presentation today.

Jan 1, 1984

By Paul D. Tomlingson

An effective maintenance program ensures the adequate availability of production equipment. In turn, this availability enables production to maximize utilization and successfully meet production targets. An overall production strategy is necessary to draw all departments toward this common effort. Only then will production targets be met. From the maintenance view this means that production must comply with PM and repair schedules. Purchasing must supply parts and materials on time. Mine engineering must not overwhelm maintenance with non-vital construction. Accounting must provide correct, timely cost information - - etc. This strategy - - its content, effectiveness and enforcement is the responsibility of the mine manager . . . his alone. This paper describes a successful approach to maintenance within this strategy.

Jan 1, 1979

By Key Rosebrook, Jennifer Laggan, Ashley Rivera

Significant quantities of waste rock at abandoned uranium mine (AUM) sites in the western United States require removal from steep slopes exceeding 45 degrees in remote locations. This prevents the use of traditional excavation equipment and poses significant challenges for safe, effective material removal. A pilot study was conducted using a spider excavator to demonstrate the feasibility of removing waste rock and transporting it to areas where conventional equipment could be employed. The spider excavator was evaluated for its effectiveness in excavation, material movement and control, container usage, dust mitigation, and ensuring human health and environmental safety. The study established constructability and engineering parameters for implementing spider excavators in these challenging environments. Key outcomes include the preservation of existing vegetation, improved waste movement control, and enhanced safety measures for workers, nearby residents, and the environment.

Feb 1, 2025

By E. McCullough

"Fostering positive community relations is a principal tenet of sustainable development, but conflict can test even the strongest of relationships. While conflict surrounding resource development projects has the potential to be destructive, it may actually pose opportunities for partnership and collaboration when managed effectively. It is therefore not only important for mineral resource professionals to recognize the financial and social costs associated with legal disputes among project stakeholders, but also for them to prioritize resolving social conflict using alternative channels that allow for win-win outcomes. A variety of dispute prevention and resolution techniques do exist, but successful practice is not yet the norm. Here we review the sources and consequences of social conflict in the context of mining projects, and discuss typical and alternative approaches to conflict management in light of their respective benefits and drawbacks. We also suggest implementation of conflict resolution lessons into resource-related university curricula as a critical step in the continued shift of the mining industry towards sustainable development. INTRODUCTION Social conflict is a recurring phenomenon in the human experience and serves as a critical mechanism for change [1-5]. It occurs when two or more parties perceive that their needs and interests are in direct competition with each other and believe they cannot be reasonably accommodated. Conflict over mineral resource activities, particularly the distribution of benefit and risk, has become an omnipresent issue throughout the world [6-7]. Contrary to common perception, however, conflict can be a positive, transformative encounter in some instances [2, 8-11]. For this to be possible, society and its acting agents must reconsider how to address conflict. What if conflict were only a challenge to try something different? It is well-understood that the mineral industries must manage an increasingly significant volume of social conflict [12-13], which can be a costly externality impacting all of whom are involved. We commonly consider conflict in a two-party sense, but this deeply over-simplifies the true number of stakeholders. Besides mining companies and community members, government policymakers and regulators, public interest groups, and judicial systems, to name a few, bear the social expenses of poorly-managed conflict [4, 6, 12, 14-22]. It is desirable for interested parties to participate actively in a constructive way to pursue their needs rather than contributing to adversarial relationships, operational problems, and legal costs [1, 4, 12]. Some mining companies are of course already working to develop more productive relationships with their stakeholders, but there is undoubtedly still a gap between ideal and common practices. This gap can inhibit collaboration and threaten the potential for mutually-beneficial resolutions to complex social issues [12]."

Jan 1, 2016

By E. McCullough

"Fostering positive community relations is a principal tenet of sustainable development, but conflict can test even the strongest of relationships. While conflict surrounding resource development projects has the potential to be destructive, it may actually pose opportunities for partnership and collaboration when managed effectively. It is therefore not only important for mineral resource professionals to recognize the financial and social costs associated with legal disputes among project stakeholders, but also for them to prioritize resolving social conflict using alternative channels that allow for win-win outcomes. A variety of dispute prevention and resolution techniques do exist, but successful practice is not yet the norm. Here we review the sources and consequences of social conflict in the context of mining projects, and discuss typical and alternative approaches to conflict management in light of their respective benefits and drawbacks. We also suggest implementation of conflict resolution lessons into resource-related university curricula as a critical step in the continued shift of the mining industry towards sustainable development. INTRODUCTION Social conflict is a recurring phenomenon in the human experience and serves as a critical mechanism for change [1-5]. It occurs when two or more parties perceive that their needs and interests are in direct competition with each other and believe they cannot be reasonably accommodated. Conflict over mineral resource activities, particularly the distribution of benefit and risk, has become an omnipresent issue throughout the world [6-7]. Contrary to common perception, however, conflict can be a positive, transformative encounter in some instances [2, 8-11]. For this to be possible, society and its acting agents must reconsider how to address conflict. What if conflict were only a challenge to try something different? It is well-understood that the mineral industries must manage an increasingly significant volume of social conflict [12-13], which can be a costly externality impacting all of whom are involved. Conflict is commonly considered in a two-party sense, but this can deeply over-simplify the true number of stakeholders. Besides mining companies and community members, government policymakers and regulators, public interest groups, and judicial systems, to name a few, bear the social expenses of poorly-managed conflict [4, 6, 12, 14-22]. It is desirable for interested parties to participate actively in a constructive way to pursue their needs rather than contributing to adversarial relationships, operational problems, and legal costs [1, 4, 12]. Some mining companies are of course already working to develop more productive relationships with their stakeholders, but there is undoubtedly still a gap between ideal and common practices. This gap can inhibit collaboration and threaten the potential for mutually-beneficial resolutions to complex social issues [12]."

Jan 1, 2016

By Greg Beckstrom

On Oct. 1-3, SME?s Twin Cities chapter (SME TC), in cooperation with the University of Minnesota ? Duluth?s Precambrian Research Center (UMD-PRC), cohosted a symposium on silica sand mining and processing. The conference was held at the Earle Brown Heritage Center near Minneapolis. The symposium was followed by a day-long field trip to operating mines, processing plants and loading facilities located in southwestern Wisconsin. Speakers and attendees at the symposium included university professors, industry experts, regulators, mining company representatives, equipment suppliers, consulting engineers and service companies. Approximately 320 people attended the conference. In addition, about 50 people who oppose mine development and the oil and gas industry showed up to voice their displeasure with the event and those companies that operate in this space.

Jan 1, 2012

By M. R. Hieb, J. R. Britt, S. P. Harteis, M. J. Sapko, E. S. Weiss, R. K. Zipf

The design requirements for mine ventilation seals have undergone a radical transformation in recent years, and these revisions have greatly increased the cost of the seal designs and their construction. For example, in the past two years, new federal regulations have increased the minimum design requirement to withstand explosion pressures from 138 kPa (20 psig) to 345 kPa (50 psig) or 827 kPa (120 psig), depending on whether the sealed mine volume is monitored continuously or not. Moreover, there is still a possibility that under certain conditions (such as detonations), even higher pressure requirements may be necessary. The ability of a monolithic, stand-alone mine seal to reliably withstand the full range of possible explosion pressures is becoming increasingly difficult and expensive. In an effort to develop a practical alternative, the West Virginia Office of Miners’ Health Safety and Training (WVOMHST) and the National Institute for Occupational Safety and Health (NIOSH) have collaborated in a research effort to develop a practical, economic and safe mine sealing technique that can enable mine seals to meet the full range of new explosion pressure design requirements. The basic idea is to use a barrier of common mine gob and rubble, in combination with a conventional mine seal, so that the pressure resulting from a gas explosion is reflected, absorbed and attenuated, and the pressure on the ventilation seal is reduced. This paper discusses some concepts and preliminary test results for a “passive mine blast attenuator” (PMBA) that can provide a useful alternative to increasingly larger and stronger stand-alone mine seals. Numerical models and full-scale experiments conducted at the NIOSH Lake Lynn Laboratory Experimental Mine (LLEM) show that the use of a PMBA can signficantly reduce the blast pressure and impulse on conventional ventilation seals.

Jan 1, 2009

By Wallace W. Wilson

It scarcely 1s possible to read a new issue of any of the principal mining trade journals without noting some mention of a major new overseas mining venture with which one or more domestic companies are involved. These projects seem to follow a fairly consistant pattern; most are large open pit mines, with relatively low grade ore bodies but huge reserves; the total price tag will be in nine significant figures and around half or more of the total cost will be for infrastructure. West1 noted that nearly $7 billion is being invested annually for new mining projects and the expansion of existing mining ventures, in the free world. He anticipates that by the year 1975 such investments would reach the $10-11 billion annual figure, and that in the five year period 1972-76 total capital requirements can be expected to aggregate around $45 billion. The proportion of this total investment which will be financed in some manner is difficult to estimate because of the variety of available financing arrangements. West estimated that around 75% of the total capital would come from internally generated funds, with the balance from external sources. Conceivably a substantially higher percentage could be attributable to external financing, especially it the trend of recent mineral development in Canada and Australia is any criterion, and of course, including local sales of equity as a part of the package.

Jan 1, 1973

The 30th annual American Mining Hall of Fame Awards Banquet and Fundraiser sponsored by the Mining Foundation of the Southwest (MFSW) will be held at the JW Marriott Star Pass Resort, Tucson, AZ on Saturday, Dec. 1, 2012. Each year, one living inductee, two recipients of Medals of Merit and up to five honorees from mining history are chosen by the MFSW for their outstanding contributions to the mining industry. Gregory H. Boyce will be the guest of honor, featured speaker and inductee into the American Mining Hall of Fame. Boyce, chairman and chief executive office of Peabody Energy, is being honored for his leadership in the coal industry.

Jan 1, 2012

By K. R. Griffin, K. D. Luxbacher, E. C. Jong

The schlieren technique describes an optical analysis method designed to enhance light distortions caused by air movement. The ability to visualize air flow has significant implications for analyzing underground mine ventilation systems, including the enhancement of surveys and models. Currently, traditional schlieren methods are impractical underground. Background-oriented schlieren (BOS) provides a solution to this problem. BOS requires two primary components, a professional quality digital camera and a schlieren background. A schlieren background is composed of a varying contrast repetitive pattern, such as black and white stripes. This background allows the camera’s sensor to capture minor light diffractions, such as those caused by air flow. Although BOS shows great potential for ventilation analysis, sensitivity is an issue. This paper seeks to validate the BOS technique for imaging flow through a regulator by comparing BOS images with traditional schlieren images. This paper also outlines initial experimental efforts used for the validation.

Jan 1, 2011