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By H. B. Humphrey

WHEN THE BUREAU OF MINES was created in 1910, the organic act had as one of its main provisions the following: That it shall be the province of said bureau and its director, under the direction of the Secretary of the Interior, to make diligent investigation of the methods of mining, especially in relation to the safely of miners and the appliances best adapted to prevent accidents, the possible improvement of renditions under which mining operations are carried on, the treatment of ores and other mineral substances, the use of explosives and electricity, the prevention of accidents, and other inquiries and technologic investigations pertinent to said industries, and from tinge to time make such public reports of the work, investigations, and information obtained as the Secretary of said department may direct, with the recommendations of such bureau. The nationwide nature of the health and safety work of the Bureau of Mines has given its representatives an opportunity to study and report on matters pertaining to health and safety in mines and related operations from the time the Bureau was established to the present. Regular annual reports and numerous additional papers and reports have been published each year to place on record and to make available the information gathered. While the basic purpose of this bulletin is to describe health and safety reports for the period January 1947 through June 1955, a selected number of earlier publica¬tions that are believed pertinent for reference purposes are included.

Jan 1, 1956

By B. Simser

Rockbursting around underground excavations continues to be a core risk for many deep mining operations. Numerous advancements in mine design, preconditioning, monitoring, mining equipment, exclusion zones, and ground support have significantly lowered the risk to mine workers. As mining continues in deeper, more challenging environments, a multitiered approach to rockburst risk mitigation, starting with mine design, is required. Both the overall mine sequence, for example, avoiding converging mining fronts, and local design “stick handling” can play an important role in risk reduction. Rockburst case studies dating back to the late 1990s up until 2024 are used to highlight risk factors and risk mitigation (tactical and strategic). Examples from several deep hard rock mines are used, generally in high horizontal stress fields (k ratios 1.5 to 2), and strong brittle rock (> 200 MPa unconfined compressive strength). Mining induced stresses as well as high in situ stress due to depth are discussed. The context is Canadian mining, which typically has highly mechanised operations, large openings and equipment. Examples from a narrow vein mine and shaft sinking are also given because neither environment is simple to mechanise, highlighting the need for other risk mitigations. A “sieve” analysis based on mine incident reports is used to show how a multi-tiered risk management plan can lower exposure to violent ground failures. A few incidents still make their way through the “sieve,” indicating a need for further improvements. Thoughts on future/ current developments, and their strategic importance are given. Ground support is the last line of defence. The proliferation of multiple styles of yielding tendons and support systems has made many choices available to rock engineering professionals. Despite the increased availability of dynamic ground support components, there are still difficulties getting clean load transfer to bolts, determining support demand, monitoring loss of capacity over time/mining, and evaluating true system capacity. Virgin development in deep high stress brittle rock can result in high strainburst exposure prior to any stoping operations. The mining process must reduce worker exposure to unsupported rockmasses. Successful preconditioning in a shaft sinking operation, the use of high early strength shotcrete, and mechanised equipment are also discussed.

Nov 24, 2025

By J. N. Van der Merwe

The paper provides an overview of subsidence research which was done by the Sasol Company in South Africa over a period of more than six years. The magnitudes of subsidence elements in South Africa are largely similar to those in the U.S.A. and Australia, as opposed to Europe. The research resulted in a subsidence prediction method with a new approach to the prediction of ground strain. The paper also describes the effects of subsidence on various commonly occurring surface structures such as roads, overland conveyor belts, pipe lines and power pylons. It is concluded that while most structures are not specifically designed to accommodate mining induced displacements, they can nontheless be undermined safely and economically with only minor precautions.

Jan 1, 1986

By Stratton-Crawley R., G. E. Agar

"A study has been done of the scale-up of laboratory bench-scale flotation to continuous plant circuit performance. It was found that the impellor speed and the air flow rate influenced the results and in this case extreme values of these operating variables were required in order to reproduce the plant rougher results in the laboratory. Despite the experimental uncertainty introduced by these extreme values, it was demonstrated that the plant performance could be predicted and experimentally reproduced with bench-scale tests.IntroductionThe mineral processing industry relies heavily on batch flotation testwork to design flowsheets, evaluate reagent s and compare various types of ore. The batch tests are generally regarded as being directly comparable within themselves, but quite often they relate poorly or not at all to continuous circuits. Obviously this dilemma generates considerable uncertainty with wide-ranging ramifications. One of the manifestations of this unfortunate situation is the commonly expressed opinion that ""it may work that way in the laboratory, but it will never work that way in the plant"".In a previous publication, a method was described whereby the results of batch bench-scale tests could be used to simulate a locked cycle flotation test series. The work to be described here is a continuation of that investigation with an extension to the simulation of an actual plant circuit. It would have been preferable to progress from laboratory batch data to a continuous pilot plant and then finally to a full-scale plant operation. However, because that possibility did not present itself, an attempt will be made to show that the performance of an existing plant circuit can be successfully simulated from batch data. The success of the procedure can be judged by the agreement among the plant results, a locked cycle test and the predicted results based on batch tests."

Jan 1, 1982

By K. M. Tompson, R. L. Armstrong, C. I. Godwin

"Tungsten skarn deposits on the Clea property in the Selwyn Mountains, Y. T., are related genetically to a quartz monzonite stock, about 500 metres in diameter at the surface. Lower Paleozoic sedimentary rocks are metamorphosed for a distance of 3 km from the stock. Tungsten-bearing skarn mineralization within the altered sedimentary rocks is of two types: sulphide-rich pods and calc-silicate beds. The most significant scheelite concentration is in calc-silicate beds near or adjacent to the quartz monzonite stock. Discordant K-Ar and Rb-Sr isotopic dates indicate that the stock is probably of early Late Cretaceous age, 94 Ma or slightly older, and that it cooled slowly. High initial 87Srl86Sr ratios and disequilibrium relationships between K-jeldspar phenocrysts and groundmass minerals in the porphyritic phase of the granitic rock , and between different granitic rock specimens, indicate contamination of crystallizing magma by old sialic continental crust which extends westward under the Selwyn Basin.This study is significant to regional tungsten exploration. Granitic rocks associated with tungsten deposits, in this part of the Canadian Cordillera at least, appear to have specific isotope characteristics that indicate they were generated at a specific time and in a particular way.IntroductionThe Clea tungsten skarn property (Fig. I) is owned by Canex Placer Limited, and lies in the Selwyn Mountains (Bostock, 1948) near the eastern margin of the Selwyn Basin (Wheeler and Gabrielse, 1972), Yukon Territory. The property covers a 20-square-mile area centered near latitude 62°47 ' north and longitude 129°52' west, and is accessible by helicopter. An airstrip and the terminus of a summer-use gravel road at MacMillan Pass, Yukon, are about 20 miles to the northnorthwest.This paper deals mainly with the geochronemetry of granitic rocks from a stock associated with tungsten mineralization on the Clea property. We show that these rocks have specific characteristics that not only define the genesis of this stock, but also have significance for regional tungsten exploration around plutons in the Canadian Cordillera."

Jan 1, 1980

This appendix contains the list of equipment, their corresponding number and their specifications with the quotations from the vendors/ manufacturers who can supply this equipment. The listings are arranged by process plant areas.

Jan 1, 1979

By John W. Fredland

Many accidents occur in the mining industry as a result of the instability of material during handling and processing operations. Accidents due to dump point instability at stockpiles, and at spoil or waste piles, for example, occur with alarming frequency. Miners must be trained to be better aware of these hazards. Information on safe working procedures at stockpiles and surge piles is provided. Mine operators must review their training and operating procedures regularly to ensure that hazardous conditions are avoided.

Jan 1, 1993

By Yan Yuan

Stable Nitroxyl polymers, such as poly (2,2,6,6-tetramenthyl-1-piperidinyloxy-4-yl methacrylate) (PTMA), are known to be effective as cathode active materials for lithium rechargeable betteries.The nitroxide radicals displayed a reversible and very rapid redox performances.We present a new synthesized method to get PTMA powder, then a doctor-blading method was used to prepare the PTMA composite electrodes, enabling successful production of homogeneous electrodes. It was characterized through FT-IR and SEM methods.The organic radical battery consists of lithium metal anode and PTMA cathode with an active material content of 65wt%.The best performance is achieved with a thin cathode that shows nearly 100% utilization of the active material (111mAh/g) at 0.1C.Through the electrochemical tests, it was found that there was a stable plateau at 3.5V while discharging. Besides, the cycling stability and rate capability were measured in detail. Although they showed a certain quantity of irreversible capacity on the first cycle, the capacity stabilized after the second cycle.

Jan 1, 2009

By J. Durkin

The Bureau of Mines has conducted field studies in coal mines throughout the United States to determine the effectiveness of electromagnetic techniques in locating miners trapped underground following a mine accident. Data from these tests have been used to generate models of expected signal and noise distributions as found above these mines. These distributions have aided in placing the expected performance of a through-the-earth electromagnetic communications technique into a probabilistic framework. Results show that at a 10% false-alarm rate, the expected probability o detecting a miner's signal" from a depth of 1000 ft is 54% at 500 ft it is 95%. These depths exceed the actual depths of 90 and 50%, respectively, of United States coal mines. Sensitivity studies have shown that at depth of 1000 ft, the probability of detection will improve approximately 2% for each dB of increase in signal-to-noise (SNR) ratio.

By Daniel G. DiCanio

This report describes a computer-based model for estimating the tangible costs of injuries and deaths from work-related accidents in underground coal mines. The study undertook to identify and quantify the elements of accident costs, including field visits to coal mines, insurance carriers, and public agencies. The mathematical models developed for each tangible element of accident cost are presented in Volume I -of the report. A listing of the computer programs which comprise the model and instructions for using the programs are presented in Volume II. Statistical distributions of mining family characteristics, data on 95 miners killed in underground accidents, and other basic data used to develop the model are presented in Volume III. Application of the model to a data base of 9,286 accidents which occured in underground bituminous coal mines during 1974 yielded a total of $56,900,000 in tangible costs to industry, mining families, and public agencies. Loss of income to the families of miners injured or killed in these accidents accounted for 47 percent of the total.

Jan 1, 1976

By Stanley G. Hutton, Robert Brubaker

"It has long been recognized that mining workers subjected to high levels of hand-transmitted vibration may suffer from vibration-related complaints. Prolonged exposure to whole-body vibration may also result in adverse effects. In this study, the effects of vibration on mining workers are examined. Previous work documenting the occurrence of vibration-related disease is reviewed. From this work, it is apparent that operators of hand-held pneumatic rock drills are exposed to a significant risk of developing vibration disease. Vibration levels recorded on the rock drills now in use are presented and shown to exceed levels recommended by a proposed ISO standard.IntroductionThe possible harmful effects of exposure to excessive vibration levels have long been recognized, particularly among operators of hand-held tools. Numerous cases have been reported of a vasospastic disorder commonly known as vibration white finger disease (VWFD), which was a term coined by the Industrial Injuries Advisory Council in Scotland in 1970(1 ), Those suffering with the disorder have frequent vasospastic attacks in which the fingers, hand and, in advanced cases, the lower arm turn white and numb, usually after a cold stimulus. Advanced stages of VWFD have been reported in which the skin becomes ulcerated and gangrenousm. The incidence of the disease has been particularly serious in the forest industry due to the extensive use of chain saws. However, in recent years, the introduction of antivibration saws has resulted in a significant reduction in the occurrence of the disease.In a recent report for the Canadian Department of Supply and Services - Energy, Mines and Resources, Hutton & Brubaker considered the effects of vibration on workers in the mining industry. In this report, the physiological and medical effects of vibration were considered, relevant vibration standards were discussed, previous vibration measurements were documented and field measurements carried out. In the present paper, the results recorded in this study will be summarized, together with results that have been previously published relating to vibration levels existing in the mining industry."

Jan 1, 1982

By F. D. Sutterfield

This study was conducted to provide experimental evidence on the effect of modifications of gasoline front-end composition on the photochemical specific reactivities of automotive emissions. Evaporative and evaporative-plus-exhaust emissions from an automobile operated with four fuels of different volatility and varying levels of C.-C5 olefins were irradiated in a 10040 environmental chamber at three sets of initial hydrocarbon-nitrogen oxides concentrations. Reactivity was measured and expressed in terms of rate-of-NO2 formation and dosages of oxidant, peroxyacetyl nitrate, and formaldehyde. The compositional changes that were necessary in reducing fuel volatility were found to have no significant effect on the reactivity of the emissions. However, replacing C4-C5 olefins with saturated components resulted in sharp decreases in all reactivity manifestations observed for the evaporative emission samples. A lesser influence (of C4-C5 olefin replacement) was found with the composite exhaust-plus-evaporative samples; the effect that was observed could be attributed to the evaporative emission portion of the sample. The data therefore suggest that saturation of front-end fuel olefins had no large effect on exhaust emission reactivity.

Jan 1, 1971

By V. J. McSweeney

This paper is directed at interested parties outside the Beach Sand Industry : the scope is quite broad. The geomorphology described is a successful working hypothesis which guided the author during prospecting and pegging campaigns : the author is not an expert in this field. The test data used in the text, for illustrative purposes, is original and may constitute a contribution to the state of the art. The operation- al and design philosophy embodied in the text is personal and describes the author's methods : all practising exponents would differ in some degree amongst themselves on these subjects. In this paper, no criticism of any existing operation or brand of equipment is intended and names are used to maintain a real contact with the subject matter. The author believes that the operational and design techniques evolved in the Beach Sand Industry under continual duress, have a wider application in the mining industry. This glimpse of the Industry is intended to enhance the respect for the present and past members. Space does not permit individual acknowledgements.

Jan 1, 1982

By Joël P. T. Kapusta

Although Peirce-Smith converting remains the workhorse in matte converting, the copper and nickel industries are still confronted with production hindrances such as tuyere blockage, excessive refractory wear and limits in the oxygen enrichment levels of the blast air. The knowledge acquired on high-pressure gas injection technology as well as the invention of the concentric tuyere for steelmaking led to the development of the Air Liquide Shrouded Injector (ALSI) technology for copper and nickel converting. Following a technology demonstration in 1997-98 with four shrouded injectors installed in a Peirce-Smith converter, Falconbridge Limited implemented ALSI Technology on a commercial scale in May 1999 as an integral part of its new Slag Make Converter at Sudbury, Ontario, Canada. The paper presents the various aspects of commissioning ALSI Technology, as well as the operating changes and injector design modifications over the five years the shrouded injectors have been in operation.

Jan 1, 2005

By Peter Radziszewski

"Comminition process costs, which typically represent an important contribution to mining operating costs, can themselves be divided roughly between energy and liner /charge wear. As such, developing the ability of predicting mill wear will allow a more accurate estimation of wear costs and therefore their control. In this paper and based on the possibility of estimating energy dissipated in impact and abrasion by using a discrete element charge motion model for mill charge motion simulation, media wear will be investigated principally as a function of three wear mechanisms : impact, abrasion and corrosion. Experimental results will be used to identify a total media wear model. Model results will be compared with real mill data from three operating Australian mines. These preliminary results show for the cases tested that the overall average error, as compared with the observed cases, is 0 % with a standard deviation of 66.1 %. Results from the Bond abrasion index tests, for the same cases investigated, give an overall error of 73 % and a standard deviation of 192.5 %. Further work is in progress to improve test procedure, validity and confidence.INTRODUCTIONComminition process costs, which typically represent an important contribution to mining operating costs, can themselves be divided roughly between energy and line / charge wear. In Greenfield situations where the estimation of operating costs is critical in determining project feasibility, the level of confidence in such estimates becomes quite important. With regards to media wear, the Bond abrasion test currently serves as the standard media wear prediction device. However, as shown [l, 21 test results once compared with actual wear rates can vary greatly. Figure 1 shows test results as compared with 15 cases. Average error over this data is 73 % with a standard deviation of 192.5 %. As such, developing the ability of more accurately predicting mill wear will allow greater confidence in wear cost estimation and therefore their control."

Jan 1, 2001

By Bill Mariucci, Gary Almeraris

All Rights Reserved. Printed in the United States of America. Information contained in this work has been obtained by SME, Inc. from sources believed to be reliable. However, neither SME nor its authors guarantee the accuracy or completeness of any information published herein, and neither SME nor its authors shall be responsible for any errors, omissions, or damages arising out of use of this information. This work is published with the understanding that SME and its authors are supplying information but are not attempting to render engineering or other professional services. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. Any statement or views presented here are those of individual authors and are not necessarily those of the SME. The mention of trade names for commercial products does not imply the approval or endorsement of SME.

Dec 1, 2009

By A. Ploszajski

This item examines the history and uses of tungsten, from discovery to superalloys via the lightbulb and electron beam instruments.

Apr 1, 2015

By A. E. Kasten

The contract objective was to develop and test automatic fire control systems for large surface machinery in surface coal mines. The effort described by the report covers the period from 31 January 1977 to 11 November 1977 and accomplished the following tasks: ? Data accumulation, mainly from visits to the major manufacturers and mine sites. ? Hazard analysis of blast-hole drill, mining shovel, and dragline. ? Recommended design concepts for automatic fire control systems for each of these vehicles. ? Detail system designs for each of these vehicles. ? Procurement of prototype systems for the blast-hole drill and mining shovel. ? Installation of the prototype systems on machines at a surface mine and demonstra¬tion of performance by fire tests on the machines.

Jan 1, 1977

By H. H. Heady

This Bureau of Mines report provides specific information regarding the analysis of ores, concentrates, and bullion. It describes analytical services provided by some Federal agencies, and discusses analytical techniques applicable to the precious metals. The appendixes list Bureau of Mines State Liaison Offices and commercial assay laboratories.

Jan 1, 1976

This report presents the results of a study for the Bureau of Mines to compare loan terms for non-fuel mineral projects in developing countries, from various International Financial Institutions (IFIs), and from private sector commercial sources. The study compares IFI and commercial loan terms for seven mineral projects in developing countries. The International Financial Institutions represented are: ? International Bank for Reconstruction and Development (World Bank) ? International Finance Corporation (IFC) ? Inter-American Development Bank (IDB) ? Asian Development Bank (ADB) ? International Monetary Fund (IMF) In addition, the costs of financing for these mineral projects were compared with the costs of long-term debt to the five largest U.S. mineral producers.

Jan 1, 1986