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By Emily Rose

The concept of risk management is applied to multiple aspects of the mining lifecycle including safety, mine design, business plan—anything that affects getting the ore to the mill for production. However, risk management is not a topic that can readily be taught in universities. Many situations require knowledge gained from experience to know how this impacts current and future operations. Recent graduates, who must develop and apply decisions based on geotechnical monitoring, likely have not developed “operational experience” and may not be aware of options and typical applications. Thorough resources that explain different monitoring systems, and when and how to implement them, are available for geotechnical professionals. Accessibility to this information can often cause information overload, leaving one unsure of where to start, without knowing where to start. This paper is intended to serve as a high-level overview of development practices, levels of risk, and risk tolerance for entry-level geotechnical and mining professionals who do not come from a geotechnical background. Summarized detail on typical monitoring practices, types of instrumentation, and how to communicate what the data indicates to key stakeholders are provided.

Feb 22, 2026

By John J. Baz-Dresch

Catalyzed diesel particulate filters (CDPF's) reduce the concentration of diesel particulate matter (DPM) and may reduce the emissions of carbon monoxide (CO) and hydrocarbons (HC) in diesel exhaust. Asamera Minerals' Cannon Mine first installed CDPF's in 1987, and currently has 12 diesel-powered vehicles equipped with CDPF's. The Cannon Mine and the U.S. Bureau of Mines collaborated to evaluate the durability and performance of a CDPF. One of the CDPF's used at the mine was periodically evaluated in the USBM's diesel emissions laboratory after 839, 1,584, and 2,881 h of in-mine service. The objectives of this report are to present results from the USBM's evaluation of this CDPF, to describe the Cannon Mine's experience and cost analysis of using CDPF's, and to make recommendations for the future use of CDPF's. CDPF's improve air quality at the Cannon Mine, but they frequently become plugged and are subject to excessive mechanical shocks and stress, shortening their useful life. Mine records indicate that CDPF's account for 0.8 to 4.9 pct of the vehicles' operating cost at the lVine. CDPF life to date has ranged from 1,671 h to more than 5,992 h. Laboratory tests of the CDPF determined that DPM removal efficiency decreased and regeneration temperature increased over time.

Jan 1, 2010

By N. Rouse

Underground raises and slots are a vital part of underground blasting operations. Raises and slots are vertical shafts or openings used for ventilation, ore passes, or creating voids in stopes. In the author’s experience, raise and slot designs can vary significantly from operation to operation or even within a single operation, sometimes for reasons unknown. The results of the various designs can differ depending on drilling accuracy, geology, and the explosives used in the design. The purpose of this paper is to summarize the recommendations found in published literature on raise and slot design in one document, while incorporating some of the author’s own experience with optimizing raise and slot designs in underground operations. Some inspiration is also included from burn round designs; small versions of raises drilled horizontally in development blasting rounds. This document includes discussion points on drillhole diameter and depth, pattern design and relief requirements, explosive types and loading recommendations, and timing. Ultimately, this document can be useful to those looking to design a raise or slot blast for the first time or for those looking to improve on the results from the raise and slot blasts used at their operations.

Jan 1, 2024

By A. C. Fieldner, SIDNEY GOTTLIEB

This report summarizes the research and technologic work of the Bureau of Mines on coal and coal products from July 1, 1947, to July 1, 1948. It is the thirteenth of a series presenting resumes based largely upon publications issued during the year . In some instances , research and testing results , not otherwise available in published form , are presented . The individual publications given as footnote references herein will provide further detail to the interested reader . The period covered by this report was marked by an ever -mounting concern for the adequacy of the Nation's fuel resources and for fuel shortages arising from an increasing demand for fuels at home and abroad . Several reports appeared which delineated the place of synthetic liquid fuels in the future fuel technology and economy of the Nation , emphasized the fact that eventually the principal raw material for the production of such fuels will bet,5,6 coal, and described the progress made by the Bureau of Mines in developing processes for the production of synthetic liquid fuels . heard testimony along similar lines . Increased awareness of the fuels problems confronting the Nation led to an authorization by the 80th Congress for the erection of an anthracite research laboratory at Schuylkill Haven , Pa . , to house expanded Bureau of Mines research on anthracite . Design of the structure was well under way by the end of the fiscal year . ( See fig . 1. ) Looking forward to expansion of Bureau research on lignite , the 80th Congress heard testimony on the problems and programs of lignite research10, 11 as a prelude to authorizing the construction of a lignite research laboratory in North Dakota .

Aug 1, 1949

By Ross W. Smith

Microorganisms are increasingly finding use in mineral processing and hydrometallurgy both for the enhancement of mineral engineering operations and for the remediation of mineral industry wastes. Some of the applications, such as biologically assisted leaching of sulfide ores and biooxidation of refractory sulfide gold ores, are established commercial processes. Others, such as the use of organisms for the removal of heavy metal ions from dilute aqueous streams, are nearing commercial application. Other uses of microorganisms are potentially possible. These include use of microorganisms in leaching non-sulfide ores, the flocculation or flotation of minerals and remediation of toxic chemicals discharged from mineral engineering operations.

Jan 1, 1993

By A Marta

Geomembrane (GMB) liners are being used more frequently for the storage or capping of mine waste due to stricter regulatory requirements relating to environmental protection. The longevity of any liner system will be a function of environmental conditions, design (including materials selection), construction and condition monitoring during operations or closure. Based on experience and case studies, this paper presents a review, from design to handover, of some of the smaller and often overlooked details that can have significant impacts on the performance of the GMB and the project overall.The topics covered will include approaches to selecting and testing GMBs to ensure they are suitable. Design considerations to aid installation and quality assurance during construction. Understanding action leakage rates and the consequences of leakage when it creates whales. Construction quality control and assurance procedures, including a brief discussion on non-destructive liner integrity testing. CITATION:Marta, A, 2018. Geomembranes – from design to handover and some of the lessons learnt, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 190–207 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By Charles Kingsley

THE PRESIDENT (DR. C. B. KINGSTON, member C.l.M.M.) expressed regret that neither of the authors of the paper was able to be present to submit the paper in person. In their absence, it would be introduced formally from the Chair. It was a clear, straightforward account of a fine piece of shaft sinking, cleverly conceived and boldly executed. He referred briefly to the distribution and nature of the Dome ore-bodies and stated that, for both the miner and the metallurgist, the mine had provided a wide range of problems of unusual interest. Discussion on the paper was then invited. MR. THOMAS PRYOR said the paper was most opportune, because the subject of internal shafts did not appear to be fully treated in current mining literature. Many members were not familiar with Canadian gold deposits and it would be of interest if the authors could give a brief description of the location of the ere deposits of the Dome mine. This information would doubtless explain why a new internal shaft was needed in a position which required such an exceptionally long cross-cut to connect it to the main hoisting shaft to surface. It would also add to the value of the paper if the authors would give some idea of the duty expected of the new shaft in terms of tons of rock hoisted and of trips engaged in the transport of men and materials, and it would be helpful if figures could be given of the total capital cost of the hoists and subsidiary excavations at the shaft top, and of the cost per foot for sinking and lining the shaft below the collar. Turning to details of the paper, one was favourably impressed by the care given to the provision of a good travelling way for men in the main cross-cut, as shown in Figure 1. It was by no means always that one could walk in comfort and safety in a working where there was a 20-in. ventilating pipe in the roof.

Jan 1, 1939

By Albert L. Toenges

This report is the second of a series describing methods and systems of mechanical mining; where operations are conducted on more than one shift. The first report, Information Circular 7014,4/ describes mining operations at 14 mines and the present paper describes operations at 11 additional mines. The purpose of this study is to analyze the advantages and disadvantages of the various types of equipment and mining systems now used where more than one shift is worked per day. Physical conditions vary in different and in the same mining districts and determine, together with economical considerations, the systems of mining and the types of mechanical loading equipment to be used. The information presented in this paper may be helpful to operators or others who may contemplate installing a mechanical mining system. The equipment used in the mines described comprises conveyors, scrapers, mobile loaders, mobile conveyors, and combination of these types. The description of the mining systems and practices at the mines investigated is detailed only as they relate to and affect mechanization. In computing the operating data in mines that are not totally mechanized, employees not working directly on production have been charged to output from mechanized sections in proportion to the percentage of mechanization. The operating data for comparing various systems are for an average working dry, as the number of men working on idle days varies greatly in different mines.

Jan 1, 1939

By D. C. McDonald

"IntroductionTHE GIANT YELLOWKNIFE property is on the west side of Yellowknife bay, Great Slave lake, N.W.T., some 600 air miles north of Edmonton. This paper deals with the underground development and mining of the complex system of orebodies which have produced, in the first fifty-six months of operation (May, 1948, to December, 1952), 652,464 tons of ore with an average grade of 0.80 ounces of •gold per ton (1).The mine has been developed from three vertical shafts designated A, B, and C. Figure l shows the positions of these openings with respect to the known ore-bearing zones and the surface plant.A shaft was sunk to a depth of 522 feet in 1945-46, primarily as a prospect shaft for investigation and development of the East Zone orebody. Drifting was carried out on the 200-and 325-foot levels. Before this development had been completed it was clear that the funds immediately available made it imperative to get revenue from production as soon as possible. By the beginning of 1946, the remarkably high-grade character of the ore in the present B Shaft area had been established by surface drilling, and the decision was made to obtain initial production from this source. Since known orebodies at shallow horizons were to be developed quickly, the choice of a suitable rock outcrop for the shaft was something of a problem."

Jan 1, 1953

By Jeffrey M. Listak

This U.S. Bureau of Mines report describes the implications of in-mine ground control on the automated or remotely controlled operation of longwall mining equipment, Perhaps the greatest challenge to longwall automation researchers is the development of systems that will continuously function in the complex and unpredictable underground environment. The high degree of environmental variability, together with conditions brought about by the extraction process, makes complete automation of longwall mining a difficult task. The intellectual thought processes and split-second decision making required to avert disasters are lost when workers are removed from the face. As many mine operators can attest, minor problems, left unresolved, can eventually accumulate and lead to catastrophic consequences. The automation process will have to assess and manage various routine problems that are otherwise resolved through worker observation and experience.

Jan 1, 1990

By E. Swartzman

"IntroductionGENERALLY, the necessity for mining coals of higher impurity content, the drive for lower costs by intensive mine mechanization, changing market requirements, and the increasing competition of oil and natural gas, have continued to result in an upward rise in coal preparation, and have necessitated a more intensive study of coal preparation problems.Increasing adoption of •continuous mining equipment, for example, is introducing new problems in coal preparation. Limited experimental work in the United States (1) shows that the effect of the continuous miner on size distribution varies with the characteristics of the seam. In some seams, the fines problem is lessened, in others it is greatly aggravated. Generally there is a decrease in the relative amount of the top sizes (plus 2 in.) and a substantial increase in the intermediate sizes (down to about 1/8 in.). Contrary to expected results•, where continuous miners with vertical-moving cutting heads are used, an increase in impurities in the slack sizes does not necessarily occur where draw-slate is taken. This is because the draw-slate tends to be kicked out in lump form. However, if a seam contains bands •and lenses of impurities they are bound to be in the mined product."

Jan 1, 1952

By Yi Luo

A massive roof fall occurred in a small room-and-pillar coal mine. The roof falls occurred under a barrier pillar in a closed coal mine located a short distance above the active mine. The extensive fractures connected the active mine with the old mine, turning them into a “combined mine.” Since completely sealing off the roof fall area is prohibitively expensive for the mine, ventilating the connected old mine became the only option. A comprehensive investigation was conducted to understand the atmospheric condition in the old mine and to find an efficient way to ventilate the “combined mine.” A set of studies involving geology, gas content, pillar stability and mine subsidence were performed to explore whether the closed mine is filled with an explosive air-methane mixture. The air quantity measurement data were used to determine the resistance of the air path formed through the fractured zone. Observations and measurements made from a tour to the underground and mine surface enabled the formulation of simple but effective ways to ventilate the old mine. The ventilation network analysis also suggested methods of control, so that sufficient ventilation air can be directed to the two parts of the old mine.

Jan 1, 2010

By I Jabouri

There are many physical factors that can affect the self-heating rate of coal. The presence of seam gas has often been referred to as inhibiting coal self-heating due to the limited access of oxidation sites created by the presence of the gas adsorbed on the coal pores. Similarly, the presence of bed moisture in the coal also acts as an inhibitor of oxidation by blocking access of air into the pores. Gas drainage of a coal seam prior to mining removes both gas and moisture from the seam. Bulk coal self-heating tests in a two-metre column on both gassy, as-mined and gas-drained, dried high volatile bituminous coal show that removal of gas and moisture from the coal accelerates the rate of self-heating to thermal runaway from 8.5 days to 4.25 days, from a start temperature of 30¦C, with an airflow of 0.25 L/min. The corresponding gas evolution pattern for each of these situations is different. Therefore, it is necessary to take this change in coal condition into consideration when developing a spontaneous combustion management plan.

Jan 1, 2005

By J Joy, D Griffiths, A Bye, G V. Kizil

Poor standards of electrical installation and maintenance continue to contribute to electrical related fatalities and injury risk in the mining industry. Electrical isolation has the potential to initiate major unwanted events (MUEs) and as such requires thorough analysis to demonstrate adequate management. There have been 719 incidents related to accidental contact with electricity over the past five years in the Queensland mining industry (Queensland Government DME, 2012a, 2012b) with the last fatality being recorded in 1997 (MESA, 2012).A project funded by the Australian Coal Association Research Program (ACARP) has developed a form of a safety case using the four-layered æCoal Mine Safety Regime (CMSR)Æ approach. The CMSR is transparent and robust as it includes full site risk assessment and special issues risk assessment to be demonstrated as part of the process.The practical application of the CMSR has been demonstrated using a longwall mining case study site, where a unique 11 kV armoured face conveyor (AFC) is in operation. The case study has involved progressive application of the requirements of each layer of the CMSR (see Figure 1) to high voltage (HV) electrical isolation related issues. The project has specifically concentrated on understanding and analysing two high priority MUEs, electric shock and unplanned movement of equipment, through Layer 1 analysis. These two MUEs are an important part of the project as they have demonstrated the steps that may be taken to satisfy the risk management processes at Layer 1 of the CMSR and have contributed to resolving issues at the other three layers of the CMSR.The analysis of HV electrical isolation has been used as an exemplar to demonstrate the CMSR process and its practical application. The CMSR is applicable to major/principal hazards management as identified by the New South Wales and Queensland jurisdictions.This paper provides an overview of the development of a form of safety case using the CMSR and introduces the case study application for HV electrical isolation risk management at underground coal mines focusing on the major unwanted event of electric shock.This project provides the mining industry with a documented, publicly accessible, form of safety case using the CMSR approach for the first time.CITATION:Kizil, G V, Griffiths, D, Bye, A and Joy, J, 2012. Using a coal mine safety regime approach to the management of high-voltage electrical isolation, in Proceedings International Mine Management 2012, pp 59-74 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By Ragnhild E. Aune, Mark William Kennedy, Shahid Akhtar, Jon Arne Bakken

"In the present study classical induction design tools are applied to the problem of heating nonmagnetic metal billets, using 50 Hz AC. As an example of great practical industrial interest, the induction heating of aluminum billets is addressed specifically. The predicted work piece power is compared with the measured work piece power for a long and a short coil, using well established methods, such as those of Burch and Davis, introduced in 1926/28, Dwight and Bagai in 1935, Baker in 1944/57, Vaughan and Williamson in 1945, and by Tudbury in 1960. A calculation methodology based on a combination of the available tools is also introduced and discussed. The method has proven to give an error of <10% of the actual work piece power. An equation for Tudbury's work piece shortness correction factor is disclosed for the first time.IntroductionInduction heating of metal billets is a practical problem, with a geometry suitable for solution using analytical methods. This paper will examine solutions related specifically to round work pieces in round coils, although the methods presented can be extended to other regular shapes of work pieces and coils[l]. The methods can also be extended to ferromagnetic materials with slight changes[2-3]. It is assumed that the coil and work piece have a consistent diameter over their entire length and that the work piece is at least as long as the coil. Correction factors can be derived for the cases where the work piece is shorter than the coil.The study of induction heating by coils began in the late 19th century with theoreticians like Heaviside[ 4]. The work of Burch and Davis[ 5-7] in the 1920' s greatly improved the theoretical understanding of induction applied to metallurgy. Many investigators in the 1930's-1950's: Dwight and Bagai[8], Baker[l-2, 9], Vaughan and Williamson[3, 10] and others[l 1-12] added to our understanding with clearer mathematics, solutions for specific applications, semi-empirical modifications and practical design tools. Much of the accumulated knowledge is available in books, such as Tudbury's practical text or Simpson's engineering guide from 1960[13-14]. Perhaps the best description and derivation of the theoretical and semi-empirical solutions can be found in Davies[15]."

Jan 1, 2011

By Pedro Lilienfeld

The objective of this program was the development, design, and fabrication of six personal-sized completely self-contained dust monitors capable of real-time as well as time-averaged monitoring of the concentration of respirable particles in coal mines, in the range of 0.1 to 100 mg/m3. The operation of these monitors is based on light scattering and passive air sampling. The design stressed overall miniaturization, ruggedness, simplicity and versatility. These instruments incorporate a single-chip CMOS microprocessor to perform all signal processing, data display and storage, and timing functions. The overall dimensions of these devices are, approximately, 10 by 10 by 5 cm.

Jan 1, 1982

By Raymond G. Travis

This report describes coal-mining methods, power requirements, coal production and distribution, and coal resources of the Bull Mountain coal field in Musselshell and Yellowstone Counties, south-central Montana Investigations in the field, were conducted by Bureau of Mines engineers The report contains a short summary of the geology and geography of the field and discusses the following information secured during the field study: Method of mining practiced at each mine, including a description of each phase of the mining cycle. Coal produced and its distribution at each mine. Power requirements and the consumption of electricity per ton of coal produced by mines. Number of non employed by mines, and the production per man per shift underground and the over-all production per man employed. Estimates of future production and power requirements for the field as a whole. This information should be of benefit to any company or individual planning the development of now coal mines in the area or the expansion of present operations.

Jan 1, 1950

By J. P. Evans

The modem &apos;copper smelter today utilizes tonnage oxygen for smelting concentrates. ,generating a high strength S02 off-gas leaving the smelter vessel. This gas stream. which also contains any unreacted oxygen, plus CO2; N2 and H20. also carries with it the volatilized portion of heavy metals in the feed, plus partly oxidized sulfide concentrates, The time/temperature history and subsequent treatment of this off-gas stream emerging from the smelting furnace exit up to the acid plant can influence the partitioning and segregation of heavy metals, in the off-gas circuit. Depending on this history. the type and characteristics of the chemical and physical reactions which occur in the gas handling system &apos;can be influenced. This fact can also be used as a tool to adjust the separation of copper from heavy metals. In this paper, the impact of different time/temperature histories of the gas, due to different furnace geometries and design. on the subsequent formation and characteristics of the smelter dust is examined. Based on the available data. several case histories drawn from examples using both bath and flash smelting technologies are analyzed from this perspective.

Jan 1, 1992

By Robert L. Lappi

This report covers the final phase of a project demonstrating the economic efficiency of cross-ridge mountaintop coal mining. A demonstration mine was established at Big Wheel Gap in northeastern Tennessee. Not only was cross-ridge mining feasible for the selected site, but parallel cut methods could not be used due to a deficit in available spoil storage. Cross-ridge mining permitted coal extraction at a cost almost identical with costs simulated by computer projections using mathematical optimization techniques. No unexpected environmental problems were encountered. Volume I is accompanied by Volume II which describes the MATHMINE Mine Simulation System, software used to support the mining demonstration.

Jan 1, 1984

By X Zhang, B McFadzean, C T. O’Connor, S Pikinini

The Platreef in South Africa contains one of the world’s largest reserves of platinum group elements. One of the major platinum group minerals (PGM) components in this ore is sperrylite (PtAs₂), which has been found to be slow floating compared to the other PGMs. In a study aimed at determining the reasons for the poor floatability of sperrylite and to improve its recovery, tests were carried out to determine the interactions of the mineral with a range of standard and novel collectors. Microflotation tests were carried out to determine the hydrophobicity of the minerals before and after adsorption of collectors. In addition, experiments were carried out to determine the enthalpy and extent of collector adsorption on the minerals and to investigate electrochemical interactions between sperrylite and selected standard collectors. The results indicated that poor collector adsorption was the major cause for the poor floatability of sperrylite. Sperrylite had both poor natural (14.5 per cent) floatability and collector-induced flotation recoveries, the highest recovery of 26 per cent being observed using PNBX collector at pH 9. Moreover, the rest potential tests showed that the interaction of sperrylite with standard collectors such as xanthates was poor. The decrease in potential after the addition of the standard collectors ranged from 7.9 mV to 24.9 mV under alkaline conditions. Furthermore, sperrylite rest potentials remained unchanged with a change in pH from basic to acidic, indicating its resistance to surface alteration. Surface alteration of the minerals is key for the chemisorption of collectors to take place on the mineral surface. This was further emphasised by flotation recoveries at low pH, where only certain collectors responded positively to a decrease in pH and these were shown to have undergone a structural change. This work has highlighted the difficulties associated with sperrylite flotation and provides some direction for future research.

Aug 24, 2022