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The 29th 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. 3, 2011. 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. Chilean Minister of Public Works and former Minister of Mining, Laurence Golborne Riveros will be the guest of honor, featured speaker and inductee into the American Mining Hall of Fame. Golborne Riveros was instrumental in managing the rescue of the 33 Chilean miners in October 2010 and in the coordination/management of the ?townsite? for family members, rescue support and the media. His engineering background and executive management skills made him ideally suited to assist in both a technical and managerial role in this emergency.

Jan 1, 2011

By Carrie Smith

Mining has historically been one of the most male-dominated industries in the world. From underground operations to executive boardrooms, the presence of women has often been slim. Women had often been excluded from operational, leadership and decision-making roles, both by cultural norms and systemic barriers. According to PwC’s Global Mine Report (2023), women represent around 14 percent of the global mining workforce. Leadership representation, however, remains sparse, with S&P Global’s 2023 report showing women holding approximately 12 percent of C-suite positions and only 3 percent of senior leadership roles globally. These figures reflect persistent gaps, but they also highlight the progress driven by a new generation of women transforming the industry. Despite the gender imbalance among mining workers, women have continuously made grand strides within the industry, resulting in pivotal changes. At the forefront of this transformation is Kimberly Morrison, one of several women who have played pivotal roles in shaping the mining sector.

Aug 1, 2025

By Donald L. Everhart

The National Uranium Resource Evaluation (NURE) program since 1974 has been designed to accomplish a comprehensive coverage of the 48 conterminous States and Alaska to evaluate the total uranium resources of the USA. This resource base includes both ore reserves and potential resources. Techniques include airborne radiometric and magnetic surveys, by hydrogeochemical surveys, surface and subsurface geologic studies, and the application of improved geochemical exploration and resource assessment methods (Table 1). In brief review, the current status of each of the five basic NURE elements is as follows: In the Aerial Surveys, in the conterminous 48 states, the flying has been completed in 89 of the NTMS 10 x 2° NURE quadrangles, and is in progress in 39 more (Figure 1). Complete quadrangle data have already been open filed for 46 additional quadrangles, for a total of 174 for which data gathering is either complete or in progress. In Alaska, the flying is complete in 42 quadrangles, and quadrangle data have been open filed for 34 more, for a total of 76 (Figure 2).

Jan 1, 1979

By T. Patten

A method for stabilizing mercury containing waste for landfill disposal would be a very cost effective solution for industry. A mercury polythiocarbonate material which is made via a metallurgical process passes a traditional TCLP for mercury. The mercury polythiocarbonate material was subjected to a more thorough evaluation, the Integrated Leaching procedures as described in Kossan (1) and Sanchez (2)The procedure involves leaching the mercury polythiocarbonate material at varying pH and sample size to liquid. The procedure had to be adapted for small sample sizes and finely divided materials due to the product characteristics and available material. The leachates were evaluated and found to be stable within common environmental pH values. The performance details on how Inter-Mountain Labs met the leaching requirements of the procedures and the analysis of mercury are presented.

Jan 1, 2012

By B. J. Timmons

An initial point that I would like to make very emphatically?and as our title might erroneously suggest for those of you old enough to remember . . . Peter Harben and myself do not intend to shoot ourselves in the foot. We derive our livelihood from a number of aggregate, industrial and other minerals producers, both here in the United States and outside. This paper, therefore, is a fence-straddler or for information purposes (we hope) only, rather than any "fur or agin" stances. In essence, some of you may consider it a U.S.G.S. publication! In fact, we hope that it serves to inspire aggregates producers to do some radical thinking, to promote introspection, and to that end it would benefit both domestic and foreign producers. The title could be shortened into a brief question of "Aggregates Travel?" with an emphatic no for the answer. In the past, the success of a construction materials venture depended upon your ability, through siting, to provide the customer f.o.b. the job site, a product at the lowest possible cost.

Jan 1, 1987

By LeRoy D. Loy

Would you believe me if I told you the constant battle between Government regulatory agencies and industry could be won by both sides? No, I'm not crazy, nor have I been soaking up any of that fine Kentucky whitelightning. But I have recently been a participant in a battle where both sides won. Actually, I'm using the term "battle" loosely because, in reality, it wasn't a battle at all - despite the fact that all the ingredients were there for a monumental struggle; i.e.. government, industry, special interest groups and a controversial issue - the development of effluent limitations. I'd like to tell you about it. Historically, on one side of the battle, government has always been ac¬cused of adopting regulations with limited evaluation of existing technologies; and then with seemingly no regard for the economic consequences. On the other side, industry gets punished by government's harsh actions because of their past "do-nothing" attitude toward pollution control. Recently, this battle seems to be losing steam, because both government and industry are beginning to realize that, ultimately, they both will lose. Even more important is the fact that both sides are, or should be, working for industrial expansion compatible with environmental protection.

Jan 1, 1977

By R. Gradnik

The continuous need for infrastructure expansion forces the mining industry to develop underground structures into more sensitive and violent environments. When underground excavation enters into deep and high stress rock conditions, geotechnical designers find themselves faced with the difficult task of selecting a rock support system that will meet today's stringent requirements. Whatever support system is chosen, it is mandatory that potential rock movement be controlled. All this has intensified the development of safety systems and new, unique solutions which can enable construction companies to go both, further and deeper, without reducing the level of safety. To address these needs, Atlas Copco developed the Roofex® bolt, specifically designed to withstand large static and dynamic deformations under prespecified load conditions. The Roofex Rock Bolt acts as stiff support up to a designable load level before the sliding effect of the mechanical frictional system is triggered and allows highly controlled rock mass movement without loosing the support function.

Jan 1, 2011

By Jürg Künzle

Underground construction is a matter of dealing with the inherent uncertainty of subsurface geology. If the encountered conditions are less favorable than the expected ones, the execution of excavation, support, ground treatment or lining works is likely to require more or different efforts than anticipated, thereby delaying the works and increasing the costs. The 2019 first edition of the FIDIC Emerald Book model contract (FEB) addresses many of the issues to which underground works give rise, including those related to differing site conditions (DSC). This paper examines how under the FEB disputes arising from or in connection with DSC could or should be avoided.

Jun 13, 2021

By J. Paraszczak

Water-powered jackleg rock drills, introduced recently in South African mines are reported to be more efficient, faster and more comfortable to operate than conventional pneumatic drills. A comparative testing of both drill types was performed in Quebec. Based on its results and time studies done in the mines, water-powered drilling has been reviewed with regards to drilling rates achieved, infrastructure needed, side effects, health and safety considerations. This study shows that the application of water-powered drills may help increase footage drilled and improve working environment, but under specific conditions. The examples of such applications are given in the conclusions.

Jan 1, 1995

By D. Kumar, R. J. Sweigard, J. Silva

The Forestry Reclamation Approach (FRA) recommends that the upper 1.22 m (4 ft) of spoil material on reclaimed surfaces should be left as uncompacted as possible to facilitate efficient tree root growth. However, the main concerns about applying the FRA to steep slopes is that the upper 1.22 m (4 ft) of loose spoil material could cause instability. Successful application of the FRA on the flat and rolling surfaces precipitated this investigation. Details of a field investigation conducted at a steep-slope mine site are available in an earlier publication (Kumar and Sweigard, 2011). A total of 70 survey monuments were driven into the slope in a regular pattern to monitor any type of slope movement. Quarterly surveying of the monuments were done to quantify slope movement, either horizontally or vertically. The methodology developed in this research for field slope movement monitoring was validated using computer model results. Analytical models based on the limit equilibrium method (LEM) and numerical models based on the finite element method (FEM) were developed for slope stability analysis. The LEM analysis was done using the Geo-Slope/W program following the simplified Bishop method. However, numerical models were developed using the PLAXIS computer program following the Mohr’s Coulomb failure criterion and strength reduction technique. The slope stability analysis was performed for two different scenarios: first with the top 1.22 m (4 ft) of loose graded spoil material and second without top loose graded spoil material. Finally, the field investigation results were compared with stability analysis results. Both of these approaches showed that application of the FRA on steep slopes is not causing any significant instability problems, due to 1.22 m (4 ft) loose graded spoil that would not exist otherwise for overly steepened slopes.

Jan 1, 2013

By Robert Stefanko

13.1-SUBSIDENCE AND GROUND MOVEMENT ROBERT STEFANKO 13.1.1-SUBSIDENCE AND FAILURE This treatment of subsidence and ground movement will be confined to subsidence control for limiting surface damage by assessing the significant parameters affecting ground movements during mining to optimize mining techniques. The material will be equally applicable to evaporite mining as well as coal but will not deal with block caving or similar systems where failure is deliberately induced and surface protection is not necessary or provided. When an underground opening is established, the original equilibrium is disturbed with resultant stress concentrations. While many factors are involved in opening stability, the span (W) undoubtedly is one of the most important factors in failure. Assuming it is relatively small, the overlying rock strata can bridge across the opening and little if any movement or convergence of top and bottom will occur. However, as the span increases, a point is reached where the stress in the overlying rock strata exceeds some strength value of the rock, and the top breaks. If the opening span is limited to some subcritical value (-We) and/or is at great depth (D), a pseudo-arch will form, achielring stability before rupture occurs to the surface. The boundary of this arch is thought to approximate an ellipse in form with the major axis vertical and equal to four times W, although there has been little field research to substantiate this theory. However, if the width of this opening is increased at this horizon to some critical value (W,) or the same span is created in a shallower seam, the overlying strata ill progressively rupture to the surface and the characteristic subsidence trough is formed (Fig. 13-1) The area of the surface affected is much greater than the area of the seam extracted, depending on the "angle of draw" (a), which is the angle between a vertical line from the edge of the opening and another line extended to a point at which subsidence tails out to zero. This angle has been found to be about 35° in Europe but is rather academic, being a function of instrument precision in detecting subsidence. Since the subsidence effect is so small at any point beyond n 25° angle, this latter may be considered the practical limit of subsidence. Further- more, indications are that the angle of draw varies with depth and nature of the strata.' In a field study over a 1,000-ft-deep potash mine in New Mexico, the maximum angle of draw was found to be 51.5°.2 So far, only a single opening has been considered. However, the width of the excavation applies to any complex mining system of entries, rooms and longwalls as long as the seam has been fully extracted and the width represents the distance from one solid rib to another. It will be noted that the amount of vertical displacement varies from point to point on the surface (s), but the maximum subsidence for a given trough occurs at the center (S). This latter value may not he equal to the maximum possible subsidence (Sm) which occurs only if a critical or super- critical (+W,) width has been exceeded (Fig. 13-1). Substantial surface damage can result when subsidence occurs. Factors affecting the amount and type of ground movement are: thickness and properties of the seam, angle of draw, width of excavation, depth and type of overburden, inclinations of strata and surface, and the amount of support left in the gob. In Europe,

Jan 1, 1973

By Erik Sundström, Magnus Nygren

Having seen significant improvements to accident rates in the last 40 years, companies in the Swedish mining industry now show a greater focus on the development of safety cultures throughout their organisations and workplaces. However, there is a lack of research examining the different safety initiatives and strategies practiced in the industry today. This study explores the potential influence and consequences such initiatives may have on the development of safety cultures in the Swedish mining industry. Twelve interviews with experts on safety initiatives from four different Swedish mining organisations were conducted and analysed in a process based on qualitative thematic analysis to identify notable connections to safety culture development. The results of these interviews highlight proclivities in the implementation and use of safety initiatives such as subjects of focus, methods and desired effects. This enables the interpretation of the conceptualisation and methods for the development of safety culture in these organisations based on their approaches to safety development. We believe the results of this study can serve as support for discussions on safety culture development in the Swedish mining industry, and be of interest for international mining industries, in addition to approaches to research in this field. However, we also believe it is important to emphasise the opportunities to approach safety culture in mining from different perspectives than those common today.

Jul 19, 2023

By Jean-Michel Rendu

On April 30, 2003, representatives of the Society for Mining, Metallurgy and Exploration, Inc.(SME) met with the staff of the Division of Corporation Finance of the U.S. Securities and Exchange Commission (SEC). The meeting was held to discuss issues related to the estimation and publication of mineral resources and ore reserves. It took place in the Washington, D.C. offices of the SEC. SEC staff members included Roger Schwall, assistant director, Division of Corporation Finance; Jill Davis, senior accountant; Roger Baer, senior mining engineer; Carl Chavez, chief mining engineer; Ron Winfrey, senior petroleum engineer; and John Murphy, senior petroleum engineer. SME committee members included JM Rendu, independent consultant and chairman of the SME Committee on Resources and Reserves; Ian Douglas, manager of deposit modeling and reserve estimation with Newmont Mining; Art Graham, director and mining engineer with Deutsche Bank Trust Company Americas; Larry Smith, chief geologist with AMEC Mining and Metals Consulting; and George MacDonald, vice president of exploration with Freeport-McMoRan Copper and Gold.

Jan 1, 2003

This paper describes major technical developments in rod mill design and operating practice since its introduction into the North American minerals industry over fifty years ago. The basic operating characteristics of the wet, overflow rod mill are described, and significant operating variables are reviewed in terms of their effects on mill power draw, power efficiency, and practical aspects of circuit operation. Key factors for improving the economic performance of rod milling circuits are identified.

Jan 1, 1986

By D. R. Nagaraj, Napoleon Tercero, Raymond Farinato

Historically, as for most reagents used in flotation, the wide-spread use of dialkyl dithiophosphinates as collectors in practical applications has preceded a detailed scientific understanding of how they work. Dialkyl dithiophosphinates are a technologically and commercially important class of collectors used in the flotation processing of Cu-Au, complex polymetallic, and precious metal ores. Plant usage has demonstrated that dithiophosphinates exhibit higher selectivity and flotation rates for Cu sulfides, galena, and precious metal values in the presence of other gangue sulfides, than the traditionally used collectors such as dialkyl dithiophosphates and xanthates. They also have an attractive health, safety, and environmental (HSE) profile. Although dithiophosphinates received little attention in the past in the flotation research community, recently, there has been significant interest in this chemistry, and numerous studies have been conducted to understand the fundamental interactions of dithiophosphinates with several base metal sulfides and precious metals. A critical overview of fundamental studies, laboratory ore flotation, and plant practice of dithiophosphinates is given in this paper. The findings from these studies are rationalized and explained by drawing on concepts and insights from coordination chemistry. A comparison between the interactions with various minerals and metals of dithiophosphinate and dithiophosphate analogues brings out some of the subtleties that seemingly minor changes in collector chemistry can make. The critical overview and analysis given here is useful in identifying gaps in knowledge regarding this important class of compounds. This in turn can provide a basis for the design of studies to advance our understanding of dithiophosphinate flotation performance.

By Lee W. Saperstein

In surface mining for coal, common practice for the disposal of preparation plant refuse is to bury it. As with surface refuse piles, these buried wastes can ignite and can also lead to ground and surface water pollution. Steps to ameliorate these problems have been devised over the years. C and K Coal Company, of Clarion, Pa., the largest Pennsylvania surface mining company, has incorporated all of these steps and added of few, of their own in their latest disposal practice. In addition to layering and compacting, C and K practices selective placement and dilution to minimize longterm problems.

Jan 1, 1977

By Hendri Silaen, Ishak Degei, Nicoll Soumilena, Arwin Edijanto, Avesiena Primadiansyah

PT Freeport Indonesia’s Deep Mill Level Zone (DMLZ) is one of three operating cave mines at the Grasberg mine complex. The DMLZ is situated in the East Ertsberg Skarn System (EESS). It is set 500 m below the operating DOZ mine and located approximately 1,500 m below the surface, making it one of the world’s deepest panel caving operations. Initial undercutting of the DMLZ commenced in the second half of 2015 and has expanded to more than 120,000 m2. High pre-mining stresses and the changes associated with caving, combined with a strong and brittle rock mass, led to significant seismicity and rock bursting. Stress and seismic management are the main challenges for the operation and have evolved significantly from initial undercutting to the present. Considerable amounts of empirical data associated with ground response have been collected, evaluated and combined with historical lessons learned from the Intermediate Ore Zone (IOZ) and Deep Ore Zone (DOZ) mines, which are located within the EESS. This has provided an improved understanding of how the various geological, geotechnical and mine design criteria relate to one another. Additionally, the information has allowed for the development and implementation of improved strategies for stress and seismic management in the DMLZ. This paper describes how these learnings have driven changes in mine geometry, layout, and support systems. Through comprehensive monitoring and detailed inspections, positive changes have been seen in the ground response, leading to an increase in footprint reliability and accelerated cave growth. The paper summarizes the key learnings at the DMLZ regarding stress and seismic management as well as the positive improvements towards sustained and safe caving operations in the DMLZ.

Apr 26, 2022

By A. Sullivan

Success in mining demands the creative application of equipment, systems and processes to the unique needs of each mineral deposit, market and, though often overlooked, the culture of the individual business. In recent years, domestic coal mining companies have become more attentive to the contribution safety and loss control programs have on their financial results. Although most have adopted fairly conventional safety programs, some have created systems and processes tailored to their unique circumstances. While each coal mining business must consider the typical risks inherent to our industry, excellence in safety is most likely achieved when a safety program is customized to meet the needs of the individual business.

Jan 1, 2000

By R. Patterson

Tracer gases have been utilized successfully in a variety of industries, each with specific releasing and sampling methods. The various attributes of tracer gases are dependent on the industry the tracers are utilized in. Tracers must be chemically and thermally stable, safe, odorless, detectable at low concentrations, have a low background concentration, and should not be naturally occurring in the environment if they are utilized in underground mining applications (Thimons et al., 1974). In addition, the tracer gas should be inexpensive, non-corrosive, non-toxic, easily transportable, readily attainable, and non-radioactive (Kennedy et al., 1987). Sulfur hexafluoride (SF6) met many of these above requirements and therefore was introduced as an ideal tracer gas to use in mining industry in the early 1970?s (Thimons et al., 1974). Due to the nature of underground mining including complicated geometry, irregular flows, turbulent flows, obstructed airways, and leakages it is difficult to use conventional anemometer and smoke tube techniques to accurately measure the effectiveness of ventilation controls (Thimons et al., 1974; Klinowski and Kennedy, 1991). There have been several applications of SF6 as a tracer gas in underground metal/non-metal and coal mines. Thimons et al. conducted early testing of SF6 in an underground limestone mine and determined that it is an effective technique for evaluating auxiliary fans, estimating volumetric flow rates in large areas, and measuring low flow velocities. A rapid face ventilation measurement method (FVM) utilizing SF6 was developed by the Bureau of Mines to make face measurements in underground coal mines (Timko and Thimons, 1982). When measuring the effectiveness of jet fans in dead headings SF6 was proven more effective than smoke tubes (Timko and Thimons, 1982). Experiments related to determining methane liberation in the gob were also conducted by injecting SF6 into a borehole (Timko and Thimons, 1982). Also, in an emergency situation where the gob had to be sealed due to a fire, SF6 was released to determine the effectiveness of the seals (Timko and Thimons, 1982).

Jan 1, 2011

By S. R. Brown

A number of relatively recent factors associated with the design of new metallurgical processing plants have made the effective training of operators a requirement for a successful start-up. Some of these factors include large capital investment in a minimum of processing lines, highly complex process control systems, and stringent regulations on plant effluent, to name a few. More than ever, operating mistakes during the start-up phase can lead to substantial delays in achieving design production, as well as problems with government authorities if permit limits are exceeded. The only way to assure your return on plant investment is to ensure new plant operators have the knowledge to properly run the plant from the outset. A comprehensive set of operating manuals specifically targeted for plant operators and foreman, written by experienced operating personnel, is the only effective way to provide the necessary information for start-up-related training.

Jan 1, 1995