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By H. J. C. MAC DONALD

THE mining engineer must have a chest of books snug enough for a camelback or to be stowed away in a canoe; at the lowest possible cost, as he needs it the most in those early years when he earns the least; but at the same time one having an unusually wide range, for he may have to cut down a forest, put up a sawmill, build mine towns, construct dams, power houses, power lines, and railroads. In fact he may be called upon for many unexpected accomplishments and all in extension of the characteristically broad demands of his profession. Suppose that an average mining engineer with a thorough theoretical training and a specialized mining education has accumulated, during a cosmopolitan experience, a complete and up-to-date library, but, unfortunately, in accepting a long term assignment to a far country he is forced to discard the greater part of

Jan 1, 1925

By S. S. M. Chan

The Bureau of Mines has investigated the structural aspects of shafts and support systems using the finite-element technique. In situ field measurements in deep, vein-type metal mines show that rock stresses are often higher in the horizontal direction than the vertical, and unequal in the horizontal plane. These data and laboratory and field-determined physical properties were used as input to analytical studies. Various design and construction parameters were investigated to deter-mine the effect on shaft stability. Rectangular shafts were studied in detail to determine the effects of applied stress ratio, shaft orientation and dimension, influence of interbedded quartzite and argillite, and rock fracturing. Various support systems were analyzed, including concrete lining, timber, and steel sets. Circular configurations were investigated to evaluate yield zones and liner thickness. Elliptical shafts and time effects were briefly evaluated to illustrate shape and time effects and demonstrate the methodology. It is shown that the magnitude, direction, and ratio of applied stress and rock mass anisotropy are keys to determining shaft stability. A realistic conceptual framework was developed with which to examine the rock and support interaction in deep mine shafts. Structural analysis techniques overcome some of the historical difficulties with shaft de-sign by defining the field data requirements and structural sensitivity of various design and construction parameters.

Jan 1, 1985

By Earle Faig

Earle Faig Along with other transportation modes, the barge industry will be greatly affected by trends in domestic coal production. Traditionally, coal has been one of the major commodities moved by barge. Now, because of events in the international energy market, coal is finally getting the recognition it deserves as a major component of the country's energy program. Perhaps even more significantly, a series of events has caused other countries to turn to the United States as a source of coal. Although the outlook for coal demand is optimistic, it will be greatly influenced by the ability of the transportation sector to handle the additional traffic. Because of its long experience in moving large quantities of coal, the barging industry is in an excellent position to capitalize on coal's increased popularity. A brief description of the barging industry should facilitate the discussion of coal as it relates to that industry. Barge companies operate on a river system that is over 40 Mm (25,000 miles) long. It includes the East and West Coasts and the Mississippi River System comprised by the Allegheny, Monongahela, Kanawha, Ohio, Illinois, Missouri, Tennessee, Cumberland, Arkansas, Warrior-Tombigbee, and Mobile Rivers, and some smaller tributaries. The Gulf Intracoastal Waterway stretching along the Gulf Coast from Brownsville, TX, to Apalachicola, FL, also is considered part of the inland waterway system. Approximately 1,800 companies operate on the inland river system and have a combined fleet of about 4,400 towboats and 28,000 barges. The fleet of towboats represents 4.8 GW (6.4 million hp) of power. The towboats comprising this fleet vary in size from a small harbor boat to a large line haul boat with 7.5 MW (10,000 hp) of power. The choice of size and power of the boat depends on a number of factors, including the size of the river and operational constraints, such as lock size, river-current rate, and water level. The choice also depends on the tow size. A single tow on a river capable of locking through 15 barges at a time handles up to almost 20 kt (22,000 st), whereas a tow on the lower Mississippi, which has no locks, can accommodate up to 41 kt (45,000 st) of cargo. Because the quality of coal is not typically damaged by exposure to the elements, it is usually moved in open hopper barges, although covered barges are used occasionally. The most frequently used size is the jumbo barge that measures 59 m (195 ft) long by 11 m (35 ft) wide by 4 m (12 ft) deep and can handle up to 1.4 kt (1,500 st) of coal. Advantages of Barge Transportation Barging offers several inherent advantages in transportation of bulk commodities like coal. First, barges can carry large quantities of product. A single jumbo hopper barge can handle 1.4 kt (1,500 st) of cargo while it takes 15 91-t (100-st) capacity rail cars or 57 trucks hauling 24 t (26 st) each to move an equivalent amount of cargo. Thus, barges can move more tonnage with less equipment than competing forms of transportation. Second, barging offers the most fuel efficient means of transportation. Less energy is required to push a load over water than to pull a similar load over land. The amount of pollution attributable to barge traffic is minimal because barges consume less fuel. Third, barging is an inexpensive form of transportation. The inland waterway industry transports about 12% of the nation's freight for about 2% of the total freight bill. This can be attributed to competition between the large number of companies on the river system and competition with other transportation modes. Fourth, barging is an environmentally safe method of transportation. Inland river routes expose fewer urban areas to hazardous substances than rail or truck. And barge spills occur less frequently than rail or truck spills. The industry does pose some disadvantages. The waterway system is constrained by the natural river network, so barges cannot travel on the most direct straight-line route. This means that barging is usually an incomplete form of transportation requiring interface with truck or rail. The industry's market is limited to those geographical areas that are located on or near the rivers. In addition, it is a time-consuming transportation mode, making it impractical for many types of commodities.

Jan 10, 1982

By Peter W. Kauffman

This Bureau of Mines publication is designed primarily to provide mine engineers and production-level mine managers with the following: 1. Information to assist them in making the decision to retreat mine and in selecting the best retreat mining technique for specific mining conditions. 2. Information on mine planning that will enable them to design mine layouts for safe and efficient retreat mining. 3. Information that will enable them to develop a section foreman's handbook. The manual has been organized to gradually increase in level of detail as the reader progresses from beginning to end. Individuals interested in an overview of retreat mining can confine themselves to the first few chapters. Those interested in mine planning, should read the middle chapters as well. Those interested in the development of a foreman's handbook should read the entire manual.

Jan 1, 1981

Martin Marietta Aluminum, Inc. followed Howmet Aluminum Corp., Revere Copper and Brass, Inc. and Anaconda Co. in lifting August prices of 99.5 percent unalloyed aluminum ingot by 3 cents to 56 cents per pound. Prior to these moves, Kaiser Aluminum and Chemical Corp. raised its June ingot listings by 4 cents to 57 cents and Consolidated Aluminum Corp., 4.5 cents to 57.5 cents. Domestic merchants increased July quotes by slightly more than 1 cent to 51.3-51.8 cents per pound. ARSENIC The Occupational Safety and Health Administration (OSHA) issued new standards, effective August 1, for worker exposure to inorganic arsenic, a toxic substance linked by OSHA to lung and lymphatic cancer. The new standard will limit worker exposure to 10 micrograms per cubic meter of air over an 8-hour period, a drastic reduction from the previous standard of 500 micrograms for a like period. Implementation of the new standards may be the most difficult and costly for copper smelters where arsenic is associated with the copper feed material but problems will also be encountered by producers of arsenic containing products such as for pesticides and herbicides. The new standards allow use of personal protective gear for workers as an interim measure until plant engineering controls can be put into effect.

Jan 1, 1978

By John Convey

This paper, a follow-up to an earlier study, gives the history of Canadian developments in mineral processing from 1921 to the fall of 1964. It deals extensively with comminution and flotation, and then goes on to cover the fields of gravity concentration, magnetic concentration, cyanidation, the processing of uranium ores, and instrumentation. Several outstanding examples of installations are given. The paper concludes with a discussion of present-day trends in mineral processing. Introduction T HE history of the developments in mineral processing in Canada from its earliest times to 1920 has already been published by one of the authors (1). The present paper is thus a logical follow-up to bring this history to date. From 1834 to 1920, mineral processing in Canada, as elsewhere in the world, was in its formative stage. This, however, prepared the ground for developments that have resulted in a mining empire from the Atlantic to the Pacific, a mining empire which could be said to be almost on par with that in the United States.

Jan 1, 1965

Two characteristics of the modern mining industry are that there is a skill shortage and that young professional people rise rapidly into highly responsible supervisory positions. With this responsibility comes the burden of identifying and managing health and safety risks. Without the benefit of a comprehensive health and safety training program, these young professionals may be putting both themselves and those under their supervision at risk. The Moura Mine explosions and the asbestos health disaster should not be just artifacts of history, but highly valued lessons that impress the need for comprehensive health and safety risk management strategies on young professionals. From the perspective of the former secretary of the Committee to implement the findings of the Moura (Disaster) Inquiry and as the former coordinator of the Coal Workers Health Scheme, key issues in occupational health and safety management systems are explored.

Jan 1, 2005

By A. J. Williams

"IntroductionAN EXCELLENT paper entitled Potash Discoveries in Western Canada (l) was presented to the 1948 Annual Meeting of the C.l.M. by L. Heber Cole, of the Department of Mines and Resources, Ottawa. In the intervening three and a half years, the search for oil and gas in Saskatchewan has added considerably to the information available on the occurrence of potash. It is the purpose of this paper to summarize the additional data. For greater clarity, it may be useful, first, to recapitulate some of the highlights of Mr. Cole's paper.Underlying the western plains of Canada there is a large deposit of sodium chloride, believed to be of early Devonian age. Associated with the sodium chloride are certain potash salts, primarily 'sylvinite,' a mechanical mixture of sodium chloride (halite) and potassium chloride (sylvite) crystals. The potash salts, when present, are usually near the top of the salt formation, though in at least one well they were found near the central part of the deposit. Cole reported on some seven wells in Saskatchewan which had encountered appreciable amounts of potash; these were the Ogema, Radville, Davidson Nos. 1 and 2, Prairie Salt Nos. 1 and 2, and Verbata wells. Depth of potash from surface ranged from 7,653 feet in the Radville well to a minimum of 3,466 feet in the Verbata well. Such depths do not compare favourably with those at which the potash is found in mines in the United States, France, and Germany, where about 1,000 feet is the average. The greatest concentration of sylvite encountered was in the Verbata well, where a bed 11 feet thick carried the equivalent of 21.64 per cent K20."

Jan 1, 1952

By Wilson W. Zoogah, Joel G. Burken, Abdullah Al Moinee, Mariam K. Al-Lami, Kwame Awuah-Offei

Soil CO2 flux serves a critical indicator of ecosystem function and carbon cycling in disturbed landscapes. This study measured and quantified temporal patterns and environmental drivers of soil respiration across fifteen revegetated treatment plots over a 12-week period (July-October 2025). Utilizing automated CO2 flux measurements, we investigated differences between treatments and quantified their relationships with soil temperature, moisture, and atmospheric pressure. One-way ANOVA revealed significant treatment effects on CO2 flux (F4, 442 =14.1, p < 0.001, η2=0.113), with amended plots exhibiting 40–50% higher mean fluxes than control plots. Weekly temporal analysis demonstrated distinct temporal patterns, with peak fluxes registering in mid-August before a gradual decline. Multiple regression analyses showed that soil temperature (β=0.043, p < 0.001) and moisture (β=2.31, p < 0.001) are the primary flux drivers, together accounting for 18.2% of total variability (adjusted R2=0.182). Atmospheric pressure had a moderate effect (β=1.13, p < 0.001), detectable only in multivariable analysis. Variance partitioning indicated that environmental factors explained more variability (18.7%) than treatment effect (10.5%), with approximately 71% of flux variability attributed to finer spatial or temporal variability. These results demonstrate that revegetation amendments enhance soil biological activity and impact geochemical cycling, and that temperature and moisture are dominant controls on respiration dynamics in reclaimed mine soils. The findings provide quantifiable benchmarks for ecosystem recovery through altering soil biology and geochemistry and for quantifying carbon sequestration potential in post-mining landscapes.

Feb 22, 2026

By Yisa Liu, Lili Xu, Shina Li, Kang Li, Jiong Dong, Zichen Yin, Ruixin Ma

With the evolving landscape of gold mineral resource development and utilization, the easily treatable gold resources are continuously decreasing, while refractory gold minerals are becoming the most important resources in the field of gold extraction. In these original ores, most of the gold is encapsulated in the lattice of pyrite and arsenopyrite, resulting in difficulty of gold transfer into the solution during the leaching process. The most effective method to solve the problem of insufficient contact between gold particles and leaching reagent is oxidation pretreatment before leaching. Different from traditional high-temperature roasting, concentrated sulfuric acid was used as both an oxidant and leaching agent in a sulfideencapsulated refractory gold ore to decompose the pyrite in the curing environment to expose the gold and improve the leaching efficiency. The experimental results showed that under the conditions of liquid solid ratio 3:1, curing temperature 240 °C and the reaction time 1.5 h, the weight loss rate and iron removal rate of the ore sample reached the highest value of 60.01% and 99.68%, respectively. The main phase of curing residue was Fe2( SO4)3, and silica was nearly the only phase after washing. At the same time, by combining the sodium thiosulfate system gold leaching method, the gold leaching rate increased from 3.67% to 81.30% before and after pretreatment with concentrated sulfuric acid.

Feb 19, 2024

By Michael J. Friedel

The permeability and flow capacity in unsaturated media are investigated by the U.S. Bureau of Mines for application to in situ copper leach mining. Moisture retention properties are derived and combined with scanning electron microprobe data to characterize the mineralogy, texture, pore size, distribution, and permeability of the host rock. Finite-element modeling is used to derive a saturated permeability, ambient degree of saturation, and assess various injection-recovery schemes. Recommended design modifications for optimization of solution distribution and maximum recovery from the rock matrix requires either (1) the injection pressures on the order of 1,500 psi and recovery wells operating in a suction mode, or (2) performing permeability enhancement, through in situ rubbling. Injection pressures can be reduced to 500 psi with improved recovery and containment of solutions.

Jan 1, 2010

By T. Bhambhani, O. Yavuzkan, D. R. Nagaraj

"Cu ore bodies commonly contain oxide Cu at the surface, with sulfide Cu content increasing with depth. The recovery of oxide Cu minerals by flotation is a longstanding challenge in the minerals industry, especially for high acid-consuming ores which would not be economical for direct acid leaching. Current practice of oxide Cu recovery involves sulfidization (often using controlled potential sulfidization or CPS) using NaSH (or Na2S) followed by flotation using traditional sulfide collectors. CPS has shown to improve recovery of oxide Cu but has the following limitations: a) HSE issues with NaSH, b) high consumption of NaSH, and c) inability to recover certain oxide Cu minerals because they are refractory to sulfidization. The oxide Cu flotation is further complicated by the presence of certain non-sulfide gangue minerals which adversely impact both recovery and selectivity.Over the past eight decades, numerous collectors have been proposed and evaluated for the direct flotation (i.e. without sulfidization) of oxide Cu minerals, the most researched of which is alkyl hydroxamate. While there are numerous publications dealing with the fundamentals of interaction of alkyl hydroxamates with single minerals, there are few publications which discuss the practical aspects of alkyl hydroxamate use in ore flotation, particularly their use with sulfidizing agents. Case studies in this paper include methods to identify optimum combinations of sulfidizing agents and oxide collectors to maximize recovery for various types of ores. It was observed that some ores do not require any sulfidization, while others require at least partial sulfidization to improve efficacy of AHX. Depending upon the ore type and mineralogy, recovery improvement in the range of 5 to 15% units, over and above that achieved with CPS, has been observed with the use of AHX. For ores requiring high dosages of NaSH, it was shown that AHX can be used to reduce the NaSH consumption significantly. The challenges associated with the presence of non-sulfide gangue minerals in oxide copper ores are included, and the use of modifiers to alleviate the associated problems and enhance the performance of AHX is discussed."

Jan 1, 2016

The Bureau of Mines is the engineering arm of the Government for mineral resources. Its mission is to carry out laboratory and field studies that will assure the wise and effective development and use of our Nation&apos;s minerals, fuels, and underground domain in order to preserve the security and enhance the welfare of our people. Specifically, studies are directed to the means by which current and emerging demands may be met, the real cost of such achievements, and the assessment of related social and economic factors. Ways are sought to fulfill our material needs in a manner that minimizes occupational hazards to workers in the industry, reduces waste, and ensures that mineral raw materials are supplied and mineral-based products are used and are disposed of efficiently, without objectionable social and environmental costs. The headquarters of the Bureau of Mines is located in Washington, D.C. The Bureau&apos;s research and development program, however, is conducted at 19 research centers and laboratories located throughout the United States.

Jan 1, 1971

By Arnold C. Love

This report discusses current research by the U.S. Bureau of Mines on the effects of whole-body vibration (WBV) and shock on underground mobile equipment operators. The highlights of a comprehensive literature review of WBV, shock, and seating are presented. Factors discussed include health and physiological effects, comfort, performance, and fatigue. Vibration data were collected from shuttle cars and ramcars at several underground coal mines in Pennsylvania, Ohio, and Illinois. The data were formatted so that they could be used to drive the Bureau&apos;s motion platform, and to compare them with ANSI S3-1979, Guide for the Evaluation of Human Exposure to Whole-Body Vibration. Human subject testing in the Bureau&apos;s vibration research laboratory evaluated the effects of two different seat angles and of the presence or absence of vibration and of foam padding on heart rate, blood pressure, and subjective discomfort. Only vibration significantly increased heart rate and systolic and mean blood pressures. Vibration and a steel seat had a significant effect on subjective discomfort. The apparatus used for these tests and the experimental procedures are described in detail. Recommendations are made for additional research on the exposure of underground mining machine operators to WBV and shock.

Jan 1, 2010

By Sally Gillies

During the 14 years since the last update to National Instrument 43-101 (NI 43-101), there have been many discussions between Canadian regulators and mining companies about mining disclosure deficiencies that arise from regulatory reviews. These discussions are not made public, and as a result, there has been some drift in how NI 43-101 is interpreted by the regulators, which in turn creates uncertainty for the mining companies trying to comply with the instrument. To reduce uncertainty in mining disclosure requirements, the Canadian Securities Administrators (CSA) has issued a notice to update the current NI 43-101 with a streamlined instrument and form. Changes and benefits are listed in the “CSA Notice and Request for Comment — Proposed Repeal and Replacement of National Instrument 43-101 Standards of Disclosure for Mineral Projects,” which is available on the Ontario, Quebec, Alberta and British Columbia Securities Commission websites. The public has been invited to comment, with the comment period ending on Oct. 10, 2025. The 43-101 Companion Policy (43-101 CP) provides an update to the views of the regulators on how the CSA staff interpret and apply certain provisions of the instrument. Collectively, some of the changes to NI 43-101, the form and 43-101 CP are likely to increase the financial and other burdens on the mining companies responsible for the disclosure, and the qualified persons (QPs) who create the disclosure. In other instances, there are missed opportunities to reduce the burden on mining companies and QPs without impacting the markets.

Sep 1, 2025

By Robert J. Tuchman

This report presents the origins of the Bureau of Mines and the evolution of the Pittsburgh Research Center from its inception to its present form. Areas of major research emphasis over the years, as well as administrative reorganizations, are discussed.

Jan 1, 1998

By George S. Rice

The prevention of coal-mine explosions has been one of the chief purposes of the Bureau of Mines. In facti the first Federal appropriation relating to mining methods, in 1908, authorized the investigation of the causes of mine explosions and the possible methods of preventing them. When that investigation started the mining industry had not determined the real causes of a succession of terrible coal-mine explosions in various countries, culminating in the great disasters at CoulTièl'es, France, and Monongah, W. Va. Coal dust as an agent of widespread explosions had been under suspicion, and watering to allay the dust was recommended by some mining engineers but the watering of coal-mine dust was adopted in comparatively few mines of the United States and Great Britain, and had not been introduced widely in any country except Germany. Rock dusting, another method of preventing explosions of coal dust, was early tested with success by the Bureau of Mines in its fist gallery at Pittsburgh and, beginnig in 1911, at the experimental mine, Bruceton, Pa. Several of the fist publications i of the bureau suggested that rock dust be used in gaseous or dusty bituminous mines, and in 1915 Technical Paper 842 strongly recommended it. Since that time additional tests in the experimental mine have fully confied this :ft judgment.

Jan 1, 1924

By Clark P. Mangelsdorf

The report consists of two parts. In Part I is a state-of the-act study of roof truss technology as of January 1979. Included are a history of the truss concept, a review of analysis techniques, a record of hardware available and equipment used in its installation and numerous examples of user experience. Part II is concerned with a study of the role of friction in the behavior of a roof truss. The appendices include laboratory tests by the author.

Jan 1, 1979

By A. J. Paul Laprairie

"ADVANCE planning of mining methods, from the first development openings to stope layout and pillar recovery, has long been accepted as a normal method of operating a mine. Recently, mine managers have become increasingly aware that advance planning of cost and accounting controls can also be considered a normal method of operation. The use of such controls is wide-spread in manufacturing industries. In mining, the gold mines of South Africa have pioneered, with marked success, in this field and have been closely associated with most of the research and field work in accounting control. Canadian mine managers are also beginning to realize the advantages of using planned costs. The control procedures which subsequently have been introduced at various mines have come to be known by such names as ""Responsibility Costing"" or Budgetary Control"".Budgetary control, the term used in this paper, is based on the concept of decentralized authority with centralized control. ;The control is achieved by measuring results against yardsticks which are in the form of budgets or standards. Bud-gets are made for the future activities of each possible operation as planned by the department head, and attention is directed to variations from this plan. Furthermore, the control process charges to each operation only those costs which are incurred directly for that operation, and which can be controlled by the person in charge. Thus, budgetary control relates results to the officials responsible for those results. Expenditures are analyzed according to the organizational structure of the mine and the people who run it, and not according to production processes."

Jan 1, 1960

By Charles Vaught, Henry J. Kellner, Michael J. Brnich, Henry P. Cole, William J. Wiehagen

In 1985, U.S. Bureau of Mines and University of Kentucky researchers began a series of studies relating to self-contained self-rescuer (SCSR) donning proficiency. During the next 5 years investigators examined a number of factors that have a bearing upon miners&apos; ability to put on and use the apparatus in an emergency: the procedure being taught; availability and utilization of training models; opportunities to practice; hygiene; and on-the-job training. This report presents an overview of that research. It is concluded that companies should adopt a hands-on training protocol that allows them to integrate SCSR donning practice into other workplace routines such as fire drills.

Jan 1, 1993