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By James Charles McHardy

During 1980-2000, the Florida Phosphate industry will deplete its Central Florida Polk County reserves. As a result, new mines will be built in the ?so-called? Southern Florida Reserve areas. These new mines will require new mining, beneficiation and tailings disposal technologies in that the southern reserves have different characteristics than have been encountered in the Central Florida deposits furthermore, government regulations will necessitate the development of new tailings and clay disposal methods. This paper reviews these challenges for the phosphate industry and how these opportunities can be expected to effect plant design and plant operating practices.

Jan 1, 1981

By G. R. Harrod

Effective mine operation demands that the right people have the right information at the right time. Caterpillar's Mining and Earthmoving Technology System (METS) meets this demand by providing "real-time" information transfer between the mine offices and machines equipped with the Caterpillar Computer Aided Earthmoving System (CAES). Transfers of mine plans from the mine planning software to CAES-equipped machines give operators access to current mine plans within minutes of their creation. Additionally, office personnel have access to a current digital terrain model (DTM) of the mine site as it is updated in "real-time" by CAES-equipped machines. METS provides mine personnel in operations, planning, and management the information they need when they need it.

Jan 1, 1998

By J. M. Stewart

The incidence of heat stroke in the South African gold mining industry is today small (less than 1 in 10 6 shifts worked). Acclimatization and selection procedures have been developed and applied throughout the industry, underground working conditions have, and are being improved, and personnel are to-day made more aware of heat stress and its consequences than ever before. Although these actions have, over the years, brought about a steady reduction in the incidence of heat stroke (see Figure 1) the small incidence of heat stroke which persists indicates that heat stress is still a problem. This realization provides the stimulus for the work presented in this paper, which has as its primary objective the development of reliable heat stress limits for men working in South African gold mines. [ ] In keeping with recent trends3I4 the approach followed in this paper is based on the physical principles of heat transfer. Detailed studies of heat transfer from humans have been undertaken,5-l1 and certain of the results form an important aspect of this Paper -

Jan 1, 1980

By A. Exikis

Simulating a ventilation network of an underground mine can help in solving complex ventilation systems with many features, selecting proper fan specifications, location and settings. Early computer systems running simple network simulations were able to provide solutions to the most common and immediate problems regarding underground mine airflow. The more advanced systems available today can perform more sophisticated modeling and simulation of a mine?s ventilation network and present their results in a more understandable and easy to communicate form. This paper presents a ventilation network case study from an underground mine. All aspects of mine ventilation network modeling and simulation are discussed as well as the results from the simulation process. The algorithms and techniques used are thoroughly explained. Some useful guidelines for the application of ventilation network software are also provided in the text.

Jan 1, 2006

By K. Morsy, S. S. Peng

This paper deals with the causes and mechanisms of a massive pillar failure in a room-and-pillar mine. The mine employed a nine-entry panel system using supersection technique under a cover ranging from 91 to 168 m (300 to 550 ft). Chain pillar squeeze and large roof-to-floor convergence were first observed at the belt transfer point on the very inby side of the main entries. It propagated out by quickly, and, within 24 hours, it had covered an area approximately 1,250-m- (4,100 ft-) long by 762-m- (2,500-ft-) wide. The failure was caught and stopped by a solid barrier pillar. Using computer modeling, this study indicates that the massive failure was initiated because of a combination of undersized chain pillars in some panels and weak immediate floor. Also, the study shows that the massive pillar failure expanded to a large area because of the absence of barrier pillars between some panels and between mains and panels. Based on computer modeling, alternative mine plans were proposed to avoid such problems.

Jan 1, 2002

By W. R. Hail

A proactive design and construct approach was used to remediate the Warm Springs Ponds Complex near Anaconda, Montana under "Superfund". The pond complex is used for treatment/settlement of heavy metals and is a repository for 19,000,000 cubic yards of tailings, precipitates and associated sediments. Remediation has resulted in treatment/settling capacity for flows up to the 100-year flood (3,300 cfs); expansion from 5 to 11 ponds in series requiring 12.5 miles of new or improved embankments with associated hydraulic structures; flood protection for the 0.5 Probable Maximum -Flood (PMF) (70,000 cfs); and closure of exposed tailings along with aquatic and terrestrial habitat enhancement.

Jan 1, 1995

By K. Morsy, S. S. Peng

This paper deals with the causes and mechanisms of massive pillar failure in a room-and-pillar mine that employed nine-entry panel system using supersection technique under a cover ranging from 91 to 168 m (300 to 550 ft). Chain pillar squeeze and large roof-to-floor convergence were first observed at the belt transfer point on the very inby side of the main entries. It propagated outby quickly and within 24 hours it had covered an area approximately 1,250 m long by 762 m wide (4,100 x 2,500 ft). The failure was caught and stopped by a solid barrier pillar. Using computer modeling, the study indicated that the massive failure was initiated due to a combination of undersized chain pillars in some panels and weak immediate floor. Also, the study shows that the massive pillar failure expanded to a large area because of no barrier pillars between some panels and between mains and panels. Based on the computer modeling, alternative mine plans have been proposed to avoid such problems.

Jan 1, 2000

By S. Thibeault, P. Filiatreault, B. Straight, D. Castendyk, L. Cameron

"Unmanned aerial vehicles (UAV), or drones, capable of collecting and retrieving water samples from pit lakes, tailings ponds and other mine water basins will revolutionize environmental programs by lowering sampling costs and reducing safety related risks. Costs typically include a boat and associated equipment, boat transportation, road maintenance, water safety devices, water safety training, and additional staff. Typically, the total cost can exceed $20,000 USD per sampling event (excluding lab analyses). Hazards include potential for drowning, unstable pit walls, and unconsolidated sediment surrounding tailings ponds. Hatch has developed a novel device for aerial drones which currently enables the collection of water samples from depths up to 390 ft (119 m). This system only requires a pilot, a sample technician, and a safe operations point overlooking the water body. Hatch anticipates this will reduce monitoring cost by at least 50% while improving safety, reducing staffing requirements and accelerating data acquisition. This manuscript demonstrates profiling and sample collection from a 95 ft (29 m) deep reservoir and a 377 ft (115 m) deep pit lake, and highlights the potential of this emerging technology. INTRODUCTION Working on or near water at active, closed, or abandoned mine sites is inherently dangerous. Between 1996 and 1999, the United States Mine Safety and Health Administration (MSHA) reported 17 fatalities involving drowning at US metal, non-metal, and coal mines (MSHA, 2000). Open pit mines which fill with water following mine closure, called pit lakes, present numerous risks to environmental monitoring teams including drowning, hypothermia, falls to the ground from the top of high walls, and rock avalanches resulting from steep, unstable pit walls. Some pit lakes are simply not easily accessible for ongoing monitoring. However, the routine collection of water samples from the entire water column on at least an annual basis is required to monitor the evolution of water quality over time, to verify the accuracy of numerical predictions, and to manage lake water chemistry in order to produce “treatable” influent to water treatment plants, and ultimately, produce acceptable site discharge water quality. As a product of these risks and the need for water sample, mining companies spend considerable expense on pit lake safety as part of monitoring. This includes training personnel for “on water” duties and hazards, purchasing or hiring specialized equipment and personnel (such as boats, boat operators, personal floatation devices, and mustang suits), stabilizing pit walls and maintaining safe access roads to the lake surface, employing spotters with direct communication to emergency medical services to watch sampling activities (because cell phones and radio signals can be blocked by pit walls), and utilizing redundancy to prepare for unexpected incidents and accidents. For example, one Canadian mining company requires pit lake water samplers to hold Marine Emergency Duties (MED) training to ensure the entire boat crew is sufficient and competent for the safe operation of the vessel, and uses three boats for water sampling: two on the water at all times, and one on the shoreline, ready to deploy. The costs of these safety mechanisms greatly adds to the overall expense associated with pit lake sampling. Consequently, environmental programs may need to reduce the frequency of pit lake sampling in order to keep monitoring programs within an acceptable budget"

Jan 1, 2017

By Kenneth Savidge

With the recent demand for increased coal production there has been a corresponding increase in the horsepower of the shearing machines. The resultant increase in the machine haulage pull has heightened the incident of haulage chain breakage resulting in machine downtime, but more seriously the danger to face personnel. This paper discusses the application of chainless haulage to longwall mining and describes the systems currently available.

Jan 1, 1978

By G. A. Perry

Cyprus Sierrita is a major producer of copper and molybdnum from its Sierrita and Twin Buttes open pit mines south of Tucson, Arizona. Both pits were started in the late 60's and are in excess of 1500 feet in depth. Sierrita has utilized a Cat 992C Remote Controlled Loader since January 1993. The loader was justified to increase SAFETY and PROFITS at Sierrita. It has exceeded all expectations. As of June 1993, it had produced additional profits totaling more than $1,500,000.

Jan 1, 1994

By H. Douglas Dahl

Thank you, Don Gentry, for your generous introduction. It is not adequate simply to say that I appreciate very much the vote of the Award Committee putting forth my name as the winner of the 1992 Daniel C. Jackling Award. To look at the list of previous Jackling Award winners is a humbling experience. The Society for Mining, Metallurgy, and Exploration has been blessed with some exceptional members over the years, and I feel privileged indeed to be included among the Jackling Award winners. During the years of my education at Penn State, my field of specialization was mining engineering, with particular emphasis in my master's and Ph.D. work on rock mechanics. But my career has not been quite so tightly focused as that. I have been involved with coal mining in all its variety - its technical aspects, both theory and practice; and its business side, dealing with management and labor, accountants and lawyers, politicians and environmentalists. And I have also been involved with related fields - construction; exploration; barges, railroads, ships and docks; supply houses; the coke business; you name it. Coming from that practical background, I believe it is most appropriate that I talk with you today about some practical matters. But I will not advise you today how to mine coal or protect roof in a hard-rock mine. You fellows know how to do that. The practical matters that I have in mind relate to policy - national policy. I will acknowledge immediately that national policy is often much less than practical, but bear with me as we explore the subject together. I am reminded of a supervisor I had early in my career. He very strongly advised me, back in 1961, to "get involved in the political process," for without objectivity injected into our national policy making, we will become a second-rate economic power. I have selected as the subject of my remarks today, "Coal and the de facto National Energy Policy." There is an energy policy relating to coal, a de facto one, and it's the one we see as a result of regulation, attitudes and culture from our nation's capital. This de facto policy is the one we in the coal business live with every business day. My thesis is very simple - Coal is, in fact, a vital part of our national energy policy and will remain so, as a practical matter, no matter what politicians may do to us, or not do to us. Coal will prevail - that will be the happy ending to my story in which, of course, we are the good guys in the black hard hats. But first, I must flesh out the plot with some other characters and with some threatening activities. There are five main characters in my story: in order of appearance - Perpetual Politics, Rampant Regulation, Selective Science, Electrification and Confident Coal. The time: the present. Perpetual Politics is always a threat to coal. When you cross the Capital Beltway into Washington, D.C., check your wallet and your gold fillings, because you're not likely to run into any friends. On Feb. 20, 1991, just over one year ago, President Bush presented to Congress his National Energy Strategy. It's a thick document of more than 260 pages, with discussions on securing our future energy supplies, increasing energy effi-

Jan 1, 1993

By Ankit Jha, Javad Sattarvand, Aaron Young

Blockchain technology is one of the prominent disruptive technologies that are being implemented in several disciplines. The application of blockchains in the mining and mineral industry can provide utility to several processes especially when the industry is undertaking digital transformation. The governing principles of blockchain technology are applicable in undertaking transformation in several processes within the mining industry. This study investigates the applications of blockchain technology within the realms of the mining industry and identifies key areas of implementation. A systematic review of publications on academic platforms relating to blockchain technology in the mining industry did not retrieve a considerable number of articles. Consequently, a thorough review of white papers and articles authored by individuals on use cases within the mining industry is compiled and presented in this review article. This review article identifies all the potential areas within the mining industry where blockchains could provide value and improve processes through their implementation. The broad area of implementation of blockchains includes supply chain, traceability in spares parts, contract management, regulatory compliance and cybersecurity.

Mar 1, 2024

By G. E. McClelland

Agglomeration techniques have been successfully applied to commerical heap leach cyanidation operations for the recovery of precious metals from low-grade ores, mine wastes, and tailings. The major parameters important for successful agglomeration pretreatment of these feed materials are discussed. Several commercial agglomeration-heap leaching operations are described. Two of the operations converted from conventional heap leaching to agglomeration-heap leaching after coventional heap leaching proved unsuccessful. Heap performance before and after agglomeration is discussed. A fairly recent operation that began production using agglomeration-heap leaching technology is also described. Two operations that processed milled tailings by agglomeration are discussed. The tailings feeds could not have been economically processed by means other than agglomeration-heap leaching.

Jan 1, 1986

By S. K. Sharma, D. A. Stanley

The US Bureau of Mines is investigating the fundamentals of the flocculation process. The objective of this study was to determine the effects of various physico-chemical parameters, namely, shear rate, polymer dosage, and polymer concentration, on floc growth and to determine the applicability of a model for predicting polymer flocculation behavior. A rapid in-line particle size analyzer was used to follow the progress of both the floc growth and the breakage as a function of time. A genetic algorithm (GA) was used to determine the unknown parameters in the model and to fit a curve to the experimental data. The results showed that the model reproduces the experimental data with only reasonable accuracy and that it was relatively insensitive to the parameters. Results of the flocculation study showed that increases in the polymer dosage had a greater effect on the time required to reach the maximum floc size than on the floc size itself: It was also determined that, given all the above parameters, the degree of slurry mixing during the flocculation process had the greatest bearing on floc growth.

Jan 1, 1995

By Jacques Mongrain, Serge Barbeau, Gary Brierley

The Communaute Urbaine de Montreal is currently involved in construction of the South Interceptor which consists of 53 kilometers (33 miles) of 1,800 mm (6.0 ft) to 5,400 mm (18.0 ft) diameter tunnels for the purpose of collecting, storing, and delivering sanitary and combined sewage to the treatment plant. Work is divided into ten separate contracts; nine of which have already been bid. The purpose of this paper is to describe construction activities that have been performed through the end of 1986 with emphasis on a general layout of facilities, a summary of subsurface conditions, and brief descriptions of actual construction activities for the six contracts where tunneling has been performed. All projects are being excavated with tunnel boring machines.

Jan 1, 1987

By R. L. Michalowski

The operation of mobile mining equipment near the crest of stockpiles and wastedumps is a potentially hazardous practice which often results in localized slope failures. A limit plasticity approach to determine the total admissible weight for moving loads near slope crests is presented. A three-dimensional analysis provides an upper bound solution to the load that can be applied to the top of the slope (dump point), and it also provides the critical distances of the load from the slope crests. The analysis accounts for the inertial forces generated by the deceleration of a moving load (e.g., a dump truck), and it also includes the drag resistance of the front wheels if the brakes are engaged. The results can be utilized to determine the safe operating distances for mobile equipment from the slope edge. This presentation will discuss the application of limit plasticity to the development of the local three-dimensional collapse mechanism. An example with realistic parameters also will be presented.

Jan 1, 1991

By T. W. Eddy

Research was conducted in which elemental mercury and its sulfide mineral (cinnabar) are removed from a copper sulfide concentrate by low temperature thermal applications. The goal of this research was to reduce, volatilize, and collect mercury vapor from concentrated smelter feed in a simulated drying environment while maintaining the chemical integrity of the residual. The study used synthesized concentrates composed of copper sulfide and mercury bearing minerals (such as cinnabar (HgS) or elemental mercury) to determine optimal residence times and temperature ranges.

Jan 1, 1996

By J. F. Fitzpatrick

This paper examines the cost elements associated with changes to gold mining practice over the last decade that result from the changes in environmental regulation and the heightened governmental and public awareness of environmental issues. The main experience base is Pegasus Gold Corporation's flagship mine, Zortman/Landusky, located in the Little Rocky Mountains of Phillips County, Montana. This operation was among the first mines that were permitted under the 1974 Montana Metal Mining Reclamation Act. In 1974, the Montana Metal Mine Reclamation Act was enacted, creating a permit system for metal and industrial mineral mines for the state of Montana. The act established the content of mine permit applications and defined parameters for the reclamation of mining disturbances. The Act can be viewed as implementing legislation for Article 9, Section 2, of Montana's Constitution, which provides that "all lands disturbed by the taking of natural resources shall be reclaimed." Pegasus Gold Corporation's Zortman/Landusky mine was among the first mines permitted under the new Act. In 1978, the initial permit applications were submitted for Zortman and Landusky, and a full Environmental Impact Statement was prepared by the Montana Department of State Lands; permits were issued in 1979. When opened later that year, the anticipated mine life for the combined Landusky and Zortman operations was approximately 18 years, based upon a proven and probable ore reserve of 43.2 million tons. Zortman/Landusky was the first large-scale heap leach gold mine in the United States. Its distinguishing feature was, and remains, a remarkably low ore grade, now .016 oz/ton. The ore is economic because it requires neither crushing nor agglomerating to leach effectively. Approximately two years after the initiation of the state's regulatory process, the Federal Land Policy Management Act (FLPMA) was enacted, establishing a mine regulatory framework for lands under the administration of the Bureau of Land Management.

Jan 1, 1992

By Jan M. Andersson

This paper will discuss the background information about rock cutting tools used for soft ground excavation, their history and evolution. A brief review of the current state of the art manufacturing technology will be presented and some parameters related to the material used in the drag and conical type pick cutters and their impact on their life and performance will be explained In addition, the selection procedures for choosing the right bit for excavation of a particular geological formation will be reviewed A set of guidelines will be provided for initial selection of the tools for various machines and rock formations. The methods for estimation of the tool life in various materials and the influencing parameters along with limitations of the rock cutting tools will be discussed as well.

Jan 1, 1998

By Neville G. W. Cook, John Kemeny

Utilizing the principles of elastic-brittle fracture mechanics, stress-displacement relationships are derived for an elastic solid containing a slip plane consisting of various configurations of collinear arrays of cracks. These models take into account the heterogeneous nature of slip planes as observed in the lab and in the field, and are relevant to the behavior of rock containing faults, joints, bedding planes, and fractures. All of our models exhibit slip weakening behavior, and show regimes of both stable (aseismic) and unstable (seismic) deformation. For given configurations of cracks and applied boundary conditions, our results show explicit ly the energy released through unstable crack growth. For instance, it is found that two equal length cracks growing together release more seismic energy than, say, a large crack growing into a small crack. Also, by allowing cracks to coalesce, our models show multiple stick-slip events without crack healing or other geochemical means.

Jan 1, 1986