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By Charles E. Mongan

The problem of roof control in the coal-mining industry is of major importance inasmuch as 65 percent of all coal-mine fatalities result from falls of roof, face, or ribs. The Health and Safety Research and Testing Center of the Federal Bureau of Mines at Pittsburgh, Pa., is engaged in several programs directed toward increasing safety in coal mining. The Roof Control Research Group has 4 programs aimed at reducing roof fall accidents. One of these programs is the use of sonic techniques to explore mine roof strata.

Jan 1, 1961

By David E. Sims

Asarco has been using computer-aided open-pit mine design since 1966. The in-house developed program package includes drill-hole analysis programs, interpolation routines, and three-dimensional open-pit design programs. The financial analysis step after pit design required that a reasonably accurate schedule be produced so that a good cash flow model could assess the feasibility of a project. The manual method of scheduling was too time-consuming for feasibility work, so a computerized scheduler was required. Since no computerized mine scheduling programs existed, we requested proposals from consulting firms to develop such a program. The selection of a consulting firm, the formulation of the contract and design specifications required about three years to accomplish. The consulting firm, Systems Control Inc. (SCI), of Palo Alto, spent over one year doing the programming and testing alone. The details of the program development were reported in "Computerized Year-by-Year Open-Pit Mine Scheduling," SME-AIME Transactions, December 1974. In June of 1973 the program, which SCI dubbed Optimum Resource Extraction or ORE, was installed. Version 1 of ORE was utilized successfully on three separate properties over a period of two years. During this time it became obvious that some of the original design specifications were restrictive, and certain modifications were required. The ORE program was submitted for modification, and after one year version 2 was operational in May of 1976. The program now consists of approximately 20,000 lines of FORTRAN source statements grouped into 190 subprograms, and runs in a 450K region of Asarco's 370/148 in Cranford, NJ. The Tucson com¬puter (370/115) is tied to the Cranford computer via a 9600 baud leased T.P. line, for running mine scheduling and other large mine planning programs.

Jan 1, 1979

By F. Ysla, M. Mendoza

This proposal, based on the CIEMAN Cajamarca - Hualgayoc initiative, focuses on “Transforming Abandoned Mine Lands’’ We aim to study and assess the feasibility of an innovative rehabilitation method. Contaminated soils will be moved from the upper to the lower site, encapsulated with geosynthetic barriers, and covered with topsoil. The decontaminated upper area will be used for planting trees and large-stemmed plants for hiking and tourism, while the lower encapsulated area will support livestock and short- stemmed crops. This study will evaluate the economic viability and multi-use potential of this technique, promoting sustainable land recovery in Cajamarca, Peru.

Feb 1, 2025

By Erica Frederickson

"Millennials. Doesn’t the word just make your blood boil? You’ve probably encountered one of those kids who think they know best despite a lack of any real experience.Hi, my name is Erica, and I am a Millennial. We often get a bad rap, sometimes for good reason. But we do have qualities that are often overlooked. For example, I am happy to share with my generation a real desire to make a difference in the world and a commitment to innovation. Does this mean I think we always have good ideas? No – especially not right away. After all, few of us came anywhere near a piece of construction equipment until arriving for our first job, as was the case for me. We may have fancy degrees, but not many of us learned to run a jackleg drill in school.Two weeks after graduating college in 2011, I packed up my bags and moved to New York City to work as a field engineer for Traylor Bros. Inc. on the Queens Bored Tunnels project (Granite/Traylor /Frontier Kemper, JV), part of NYC MTA’s multi-billion dollar Long Island Railroad East Side Access project. It was here I became acquainted with the notorious New York City union workers. Perhaps the greatest challenge of my career thus far was earning the respect of the field supervision and craft workers on this first project.The first time I asked a maintenance mechanic to clean a piece of equipment in accordance with our maintenance protocol I got a flat-out “No.” It was the most powerless I had ever felt. But why should these experienced workers trust a 21-year-old girl with her civil engineering degree and no prior experience? I realized no employee on the job had any reason to listen to me — not until I proved my worth. Fortunately, I arrived on the job site just as we were commissioning the slurry plant for the first tunnel drive. I dove into learning as much about the slurry tunneling process as possible and was able to quickly pick up the ins and outs of running the slurry separation plant. As none of the other engineers or management had first-hand experience on a slurry tunneling job, I soon became the go-to engineer in the slurry plant. No one questioned me if I asked to have something done around the plant after that, or if they did, they quickly learned that I had a convincing answer as to the need for the task. I was even able to play a large role in shaping our slurry monitoring and control methodology."

Jan 1, 2015

Heap leaching has become one of the prime technologies used for the recovery of precious metals from low-grade ores over the past ten years. The recovery process involves mining and stacking the ore on engineered leach pads, with or without crushing and/or agglomeration, followed by leaching with a low concentration sodium cyanide solution. The metal-bearing, pregnant solution is then processed by zinc precipitation or activated carbon absorption to extract the precious metals. The leaching process continues until all economic metal values are removed at which time the spent heap leach pads, the leached materials and excess process solutions require decommissioning. The management of these solutions may present a potential challenge for successful and environmentally sound decommissioning due to their composition, volume or continuity of generation from the spent ore even though active leaching has been terminated. The principal objectives of solution management in decommissioning spent heap leach pads are to meet all operative environmental regulations in a cost-effective manner and to leave the pads in a condition where they do not present a long-term liability either to the operator or to the environment. This involves the reduction in volume of the residual process solutions and/or treatment of these solutions to where they meet applicable water quality criteria. In the past, the environmental and economic aspects of decommissioning and solution management have been overlooked or under-estimated during the planning of mining operations. As a result, there is a potential for long-term liabilities and costs to be recognized only at the end of active leaching, a time at which operating revenues and cash-flow are minimal. Therefore, the decommissioning process requires addressing at the mine planning stage and agencies now require that a plan for solution management after the cessation of operations be submitted prior to initiation of mining. This paper discusses aspects of process solution management during decommissioning, both in terms of quantity and quality, and how potential issues may be recognized and planned for in the initial stages of heap leach design.

Jan 1, 1992

By O. Porterfield, M. O’Kane, M. Endersby

BHP Iron Ore initiated research programs in January 1995 to develop long-term plans for decommissioning waste rock material at its Mt. Whaleback operation. More than 2 Gt (2.2 billion st) of waste rock were deposited during the past 30 years. Ultimately, a total of 4 Gt (4.4 billion st) will be deposited in waste rock dumps constructed near the open pit. The Mt. Whaleback operation is located in a semiarid climate adjacent to Newman, Western Australia. The primary research program includes the development of technology for the long-term performance of the waste rock dumps with respect to vegetation, slope stability, surface runoff, erosion and water infiltration. This paper focuses on the design and implementation of a cover system to prevent water infiltration to the underlying waste rock. Data obtained from a laboratory program and from soil-atmosphere modeling was used to design horizontal field test plots. The construction of the horizontal surface field test plots is discussed together with the field instruments installed to monitor performance. The cover system is designed to maximize infiltration during wet periods for subsequent evapotranspiration while minimizing surface runoff. The result is a near-zero net infiltration to the underlying waste material. An important feature of the design is the use of run-of-mine waste material as the cover material. Monitoring is in progress and will continue for at least two annual wet/dry cycles. The optimum cover system should minimize the net infiltration of water to the underlying waste rock while maintaining physical and ecological integrity for long-term performance.

Jan 1, 2000

By Siegfried Zell

INTRODUCTION Denmark is a small country with a population of about 5.5 million in the north of Europe. A substantial part of Denmark consists of islands, and the Danes have been familiar with ferry links between their islands for ages. However, their wish for fixed links has resulted in the con¬struction of bridges between most of Denmark's islands in this century. (Fig. 1) A fixed link across the Store Belt or Great Belt, Denmark's most important waterway bet¬ween the island of Fyn and main island of Sjaelland, on which the capital of Copenhagen is situated, has remained to be constructed hitherto. In 1987, the Danish government decided that the Great Belt should be crossed by a fixed link, incorporating a two-track railway line and four-lane motorway. The Storebaelt Forbindelsen AS, a joint stock company in the sole ownership of the Dan¬ish state, has been established for the purpose of planning, constructing and operating the Great Belt Link. The company will refinance the construction project by charging toll to the motorway users and fees to the state railway. Here it should be mentioned that Denmark and Sweden are about to jointly realize the fixed rail and road link across the Øresund or The Sound between Denmark and Sweden on the basis of the realization model of the Great Belt link. At present, the project is at the com¬petitive tendering or contract awarding stage. In the near future, also the third fixed link of comparable extent, that is the crossing of the Fehmarn Belt between Denmark and Germany, will go into the decisive projecting stage prob¬ably in conformity with the aforementioned pattern. Going back to the Great Belt, it should be noted that this fixed link involves three exten¬sive sections and has been under construction since December 1988.

Jan 1, 1995

By Wallace N. Thomas

The present interest in large diameter grinding mills and the rapidly rising cost of the drive in proportion to the cost of the mill establishes a need to explore the drive system in detail. The drive for a seven to eight thousand horsepower mill will cost from 1350 thousand to $600 thousand which represents nearly half the total cost of the mill package, and requires as much building space as the mill proper. Some of the drive components require a longer time to manufacture and the installation time and costs are equal to those for the mill. It is apparent that the drive has become a dominant factor in the overall mill design consideration. A new plant requires a tremendous investment in both time and money. With the high degree of competition in the mining industry, low capital cost is an exceedingly important factor in the development of a project. It is just as important, however, to insure that the equipment is going to perform satisfactorily for the anticipated life of the project without adding unplanned operating, maintenance and replacement costs. This is the position in which the engineer or designer usually finds himself and is really one of his primary functions -- establishing a realistic compromise between cost and performance.

Jan 1, 1969

By David Hatem, Paul Madsen, Daniel Adams, James Morrison, Randall Essex

Managing commercial risks associated with subsurface construction may be the greatest challenge the underground industry faces. The Geotechnical Baseline Report (GBR) was developed in the U.S. to help manage those commercial risks, and to stem increasing litigation in the industry. A guidelines document by the American Society of Civil Engineers was published in 1997 and was updated in 2007. This paper provides an historical perspective, overviews the main objectives of a GBR, presents issues and trends that instigated the need to update the 2007 publication, and describes the process that will lead to a new GBR guidelines publication in 2022

Dec 1, 2022

By Trevor Riters

Advancements in Emerson’s instrumentation technology have brought value and efficiencies to the mining industry. Some think of instrumentation as basic sensors and valves, but with our solutions, we equip operators with real time, accurate, and reliable data that they can use to operate more effectively. Working with Caltrol, an Emerson Impact Partner, we successfully engineered wireless skids for a leach pad to provide precise measurement and control of raffinate solution to many of the large mine sites in Arizona.

Feb 1, 2025

By P. C. Thakur

Mine productivity, measured by the output of minerals per manshift, depends on a number of factors including physical conditions of the minable seam, type of mining equipment, management techniques, worker attitudes and governing jaws and regulations. The greatest scope of improving productivity lies, perhaps, in modifying physical conditions to an advantage and using highly productive equipment. In the case of coal mines, increased productivity can be achieved by (i) obtaining prior knowledge of the mineable property, e.g., the grade and thickness of, the coal seam, presence of sand channels, faults, etc., (ii) eliminating conditions that hamper production, e.g., high emissions of methane and water, and (iii) using more productive mining techniques. Conoco/Consol's (Conoco Inc. and Consolidation! bal Company, a fully-owned subsidiary) horizontal drilling system was developed with the hove objectives in mind. It can drill 75 to 1001 in diameter boreholes to depths of more than 600 1 and maintain the borehole in a preselected horizon. Such boreholes can be utilized for premining exploration of the coal seam, for removing methane and water and in devising mining techniques with high productivity. The purpose of this paper is to describe the horizontal drilling system briefly and to discuss its applications in the above-mentioned- areas.

Jan 1, 1980

By G. S. S. Raman, M. S. Klima

Coal refuse slurries stored in tailings impoundments can potentially lead to environmental concerns such as effluent seepage, property devaluation, and in extreme cases, dam failures. Pressure filtration offers an opportunity to reduce the impoundment requirements by providing significantly drier solids. A full-factorial design was used to study the effects of temperature and pH on dewatering a refuse slurry obtained from a coal preparation facility in Pennsylvania, USA. The experimental results indicated a strong effect of temperature on cake moisture as the cake moisture after about 2800 s was 22% at 43 °C and only 36% at 10 °C for tests conducted at pH 3. ANOVA results confirmed the statistical significance of pH, temperature, and their interaction effect. Also, the results showed no significant differences between the tests conducted near neutral and alkaline pH values at low and ambient temperatures. On the other hand, Tukey’s test indicated higher reductions in cake moisture at higher temperatures for lower pH values. This study affirms the need to monitor and control the pressure filtration process as throughput could significantly vary with changes in temperature and slurry conditions.

By Joel Lööw, Johan Larsson, Stig Vinberg, Malin Mattson Molnar, Mats Jakobsson, Jan Johansson

The mining industry is undergoing rapid transformation, driven by technological advancements, sustainability concerns and demographic shifts. This transformation will put more younger people in management positions. This study provides valuable insights into the leadership behaviors of younger and older managers within a large Swedish mining company, highlighting the importance of managerial experience and targeted training programs to foster effective leadership, particularly in the context of change management. The findings emphasize the need to create work environments that support managers to develop their leadership, contributing to improved employee well-being, operational efficiency, and adaptation to the changing demands of the modern mining sector.

May 1, 2025

By Brij M. Moudgil

Florida produced more than eighty percent of domestic phosphate during 1974. This amounted to more than thirty-five million short tons. Ninety percent of this production was used in the production of fertilizers. Other uses of phosphate include food preservatives, fabric dyes, optical glass, photographic films, soaps, plastics, pharmaceuticals and animal feed ingredients. Marketable phosphate rock projections for the nest decade forecast a very healthy growth for the Florida phosphate industry. Associated with the expansion, however, are the corresponding problems of water conservation, air and water pollution and land reclamation. Recognizing mining as an interim land use, the industry is presently engaged in a very active reclamation program. The proximity of the central Florida deposits to rapidly developing urban areas makes it important to undertake successful and well planned reclamation programs. Water use and conservation is of vitil importance to the industry. Water withdrawal from existing aquifers and discharges into drainage systems are closely regulated by state agencies. Water is stored and recycled to maximize usage. In some instances water is even returned to major aquifers through a series of recharge or connector wells. The phosphate industry has spent over 200 million dollars in the past decade for research, development and implementation of pollution abatement and water conservation systems.1 The following discussion outlines various phases of phosphate mining in central Florida today, with emphasis on research in waste disposal techniques and progressive land reclamation programs.

Jan 1, 1975

"The 33rd 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 Tucson Starr Pass Resort & Spa on Saturday, Dec. 5, 2015. Each year, one living Hall of Fame inductee, two Medal of Merit recipients, several honorees from Mining’s Past, an Industry Partnership Award and a Special Citation are recognized for their respective contributions to the mining industry.Conrad E. Huss, cofounder of M3 Engineering & Technology Corp. located in Tucson, AZ, will be honored as the 2015 Hall of Fame Inductee and will serve as the keynote speaker at the awards banquet. Huss has served his company as chairman of the board for its entire 30 years and guided M3 to become a full discipline firm. Now M3 offers complete project execution through engineering, procurement and construction management procedure and has become a major engineer of large observatories around the world. The company now has more than 1,000 employees with offices in Arizona, North Carolina, Mexico, Argentina and is incorporated in Guatemala, Peru and Canada.The Medal of Merit will be awarded to Charles Michael (Mick) Lownds, founder of his eponymous consulting firm in Salt Lake City, UT, for his 42 years in commercial explosives following tenure at Sasol and at Orica. Originally from South Africa, Lownds immigrated to the United States in 1998 and has made significant advancement on electronic initiation systems. Lownds has published numerous technical papers, is an inventor with 12 awarded United States patents and was also the recipient of the President’s Award from the International Society of Explosives Engineers in 2000.Medal of Merit for young professionals will be awarded to Fiorella Giana, Freeport- McMoRan Inc.’s (FCX) mine manager at Bagdad. Born in Buenos Aires, Argentina, Giana left the small cattle farm where she was raised in 2001 to pursue higher education in the United States. For the past decade at FCX, as a result of her extraordinary combination of technical skill, leadership and commitment to excellence, she has been given positions of progressively greater responsibility from an entry level engineer to senior mine engineer, to chief engineer and now as mine manager, a position rarely held by woman."

Jan 1, 2015

By William R. Groseclose, Kenneth D. Schoeman

The Buckskin Mountains Tunnel is a key link in the Bureau of Reclamation's Central Arizona Project. The 22-foot (6.7-m) diameter tunnel is being bored in a north-northwesterly direction through volcanic rock near Lake Havasu in western Arizona. The 6.9-mile (11-km) conveyance tunnel will carry up to 3,000 cfs (85 cu m per sec) of water through the Buckskin Mountains as part of the Granite Reef Aqueduct. The water for the project will be drawn from Lake Havasu behind Parker Dam on the Colorado River and pumped some 800 feet (244 m) above the lake to the inlet portal of the free flow tunnel where it begins its 190-mile (300-km) journey to Phoenix, Arizona, and beyond into Orme Reservoir (figure 1). Precast concrete segments are being used as a single system initial support and final lining in the tunnel being excavated by a tunnel boring machine specially designed and built for the job by The Robbins Company. J. F. Shea Company, Inc., of Walnut, California, is constructing the tunnel for the Bureau of Reclamation.

Jan 1, 1976

By F. Scott Carpenter

During the past several years, more frequent reference to Wollastonite has appeared in print, both in this country and abroad. The reason for this is the apparent growing interest in this mineral as it approaches commercial maturity. Twelve years ago, wollastonite was available in only limited commercial quantity. In 1933, a deposit in California was worked for a short time to provide a calcium silicate raw .material for the manufacture of mineral wool* It was not until the spring of 1953 that Cabot Corporation put into operation a modem commercial plant to produce this material in a variety of grades. These grades covered both a range of particle size and of particle shape. At that time, applications for wollastonite were largely speculative, although a few commercial applications in glass frits and welding fluxes did exist, For all practical purposes, it was a new material for which few commercial uses had been fully proven.

Jan 1, 1964

"A commercially available Through-the-Earth (TTE) communications system was evaluated at an active underground longwall mine in West Virginia. This TTE system uses electric field (E-field) sensing to send text based communications using two separate antenna arrays connected in parallel. Each antenna array is composed of interconnected, grounded metallic rods or other such structures. Two-way communication between subsurface locations was investigated in this study using various antenna configurations. This field study was conducted as a part of a larger multi-site evaluation of available TTE systems in an effort to determine their operational sensitivity. INTRODUCTION Wireless, Through-the-Earth (TTE) communication technology is designed to achieve point to point communication through solid strata using very low frequency (VLF) and ultra-low frequency (ULF) electromagnetic waves. This ability allows TTE communication to function without the need for intermediary communications infrastructure, such as repeaters. As a result, such communication systems have the potential to provide reliable, robust communications between surface and underground personnel. Exploration into the use of TTE technology for this purpose dates back to the 1920s (Jakosky and Zellers 1924; Pittman, Church and McLendon 1985), but U.S. permissibility requirements slowed the development of TTE equipment for widespread implementation (Durkin 1980; Pittman, Church and McLendon 1985). One of the primary challenges in producing wireless TTE communications is the counteraction of signal attenuation when propagating through solid strata (Barkand, Damiano and Shumaker 2006; Wadley 1949). The long wavelengths of TTE transmissions make them well-suited for reducing the rate of attenuation. However, even when operating within the VLF to ULF range, the performance of TTE systems is still affected by geologic and anthropogenic factors (Geyer 1973; Geyer and Keller 1976; Geyer, Keller and Ohya 1974; Jakosky and Zellers 1924; Large, Ball and Farstad 1973). Although commercially developed TTE systems have demonstrated the ability to communicate through a variety of conditions, their range and performance have been highly varied (Barkand, Damiano and Shumaker 2006; Geyer and Keller 1976; Geyer, Keller and Ohya 1974; Ilsley, Freeman and Zellers 1928; Jakosky and Zellers 1924; Yenchek et al. 2012)."

Jan 1, 2016

By Jeff Easton, J Johnson, D. Foot

The Mina Santa Rosa mine in Panama was the victim of a mine closure 24 years ago that left the community in dire straits. The mine showed the potential resources of greater than 1M ounces of gold and 4.5M ounces of silver. Veragold Mining Company decided to reopen the mine and address all the issues that were involved in the startup of an historic mine. This paper provides methods to restore the community trust, provide a transparent process, and develop an environmentally sound flowsheet. Immense scrutiny surrounded the Tailings Storage Facility, and the company developed a plan focused on paste thickening and surface stacking to eliminate the need for a conventional tailings’ facility. Paste thickener principles and benefits are also provided.

Feb 1, 2024

By Thomas A. Simpson

Hydrogeological techniques were used to solve problems of slope stability in open-pit mines of the Eufaula bauxite district, Alabama. Geologic and hydrologic data were evaluated and used to design a system of dewatering wells to enable the operators to mine bauxite more efficiently and economically. Walls of open-pit mines in the district were subsequently stabilized by the operation of the dewatering system. Three open-pit mines, each at varying stages of the mining process, of the A. P. Green Refractories Company, were used to develop a sequential series of guidelines that indicate how to effectively remove ground water from the formations surrounding the ore bodies in the district. The use of sound engineering principles in well design, in combination with the correct interpretation of the pit hydrology provided the basis for solutions of the slope- stabilization problem aided in the economical removal of bauxite from mines of the district.

Jan 1, 1975