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By A. G. Mayton, D. H. Ambrose, C. C. Jobes, N. K. Kittusamy

In a systematic study, the National Institute for Occupational Safety and Health (NIOSH) evaluated seat designs in low- and mid-seam shuttle cars during production operations at two underground coal mines in southern West Virginia. The purpose was to support, with additional data, earlier findings that NIOSH ergonomic seat designs (featuring viscoelastic foam padding and lower-back support) may help reduce health risks to operators of coal mine shuttle cars. Eight shuttle car operators evaluated seven seat designs (one already in use in each vehicle and five NIOSH designs) relative to perceived and measured whole-body vibration (WBV) exposure (including vehicle jarring/jolting) and discomfort. Operators’ perceptions using a visual analog scale (VAS) and questionnaire ratings were compared with International Standards Organization (ISO) 2631-1:1985 fatigue-decreased proficiency (FDP) limits and measured WBV levels on low- and mid-seam shuttle cars. Objective and subjective data results indicated that NIOSH seat designs (with added adjustability, lower-back support and improved seat padding) performed better to reduce vehicle jarring/jolting levels and that shuttle car operators favored them over existing seat designs. The NIOSH low- and mid-seam shuttle car seats showed 45 to 77 percent better performance in FDP and 9 to 60 percent better performance overall in operators’ ratings. Considering the VAS results for low- and mid-seam shuttle cars under no-load conditions, operators rated the level of jarring/jolting 18 to 89 percent lower with the NIOSH seats. Reductions in measured vehicle jarring/jolting were 19 to 46 percent for the three-directional vector sum accelerations relative to the existing seats on the low- and mid-seam shuttle cars. Questionnaire responses indicated that operators for both shuttle car models rated NIOSH seat designs as more comfortable overall. Vehicle operators most frequently suggested adding armrests to improve the seats on the mid-seam shuttle car. A suggested improvement for the low-seam shuttle car was to make the seat a better fit for the operator compartment, which would enhance clearance between the operator and vehicle controls and allow for better seat adjustment and operator visibility.

Jan 1, 2009

By Christopher Mark

Severe dynamic multiple seam interactions can occur when active mine workings are subsided by underlying mining activity. The most dramatic events are usually caused by longwall mining or pillar recovery beneath open, overlying entries. But pillars in abandoned workings can also fail and cause subsidence and damage an overlying mine. This paper describes a case history in which an apparent ?pillar squeeze? in the abandoned workings of a lower seam was initiated during retreat mining in an upper seam. The event subsequently extended more than 1,500 ft and ultimately closed the upper seam mine. Analysis indicated that the pillars in the lower mine were adequately sized for the lower seam mining and were not affected by the initial development above them. When retreat mining in the upper seam had progressed several hundred feet, however, the pillars located directly beneath the pillar line were overloaded, and an extensive squeeze initiated in the underlying workings. The squeeze, in turn, subsided the overlying workings, causing widespread rib falls and roof instability. Previous examples of dynamic multiple seam interactions resulting from delayed subsidence of underlying workings have been reported in the literature. This is, apparently, the first recorded incident in which pillar recovery in an active mine triggered pillar failure in an underlying mine, which then triggered a dynamic interaction that impacted the active overlying seam.

Jan 1, 2012

By F F. Pitard

The comparison between J Visman and C O Ingamells’ works with P M Gy’s works has been the object of intense debates in the past. Such negative debates inevitably resulted in a loss of many good opportunities. The author’s long experience in applying works of these three authors led to the pragmatic conclusion that it is relatively easy to integrate everything Visman and Ingamells created into the Theory of Sampling; therefore, it is suggested that the compatibility has been vastly overlooked, and a correction for such anomaly is recommended. It is important to emphasise that Visman and Ingamells works may be beneficial and provide relevant, harmonious additions in some areas, and ultimately offer attractive possibilities to sampling practitioners. Such additions may enhance our capabilities to predict sampling difficulties by using a stronger strategy and to design better sampling experiments that would allow us to further understand the heterogeneity of minor constituents, and especially trace constituents. Basically, the suggested integration is essential for sampling trace constituents in the environment, in food, in chemicals and in the pharmaceutical industries.CITATION:Pitard, F F, 2017. Integration of Visman and Ingamells’ works into the Theory of Sampling – a necessity to expand possibilities in sampling practices, in Proceedings Eighth World Conference on Sampling and Blending , pp 55–62 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

By Charles W. Merrill

AN ADEQUATE, dependable, and continuing supply of raw materials is indispensable to tile the United States and its industries in meeting the needs of an expanding Population, a rising standard of living, and the national security. The primary responsibility for appraising the status of the country's mineral supply and for making appropriate recommendations within the executive branch and to the Congress has been pinned in the U.S. Department of the Interior. In fulfilling its role of governmental responsibility for raw-material supplies and their efficient utilization, the Bureau of Mines has analyzed the factors in current and future mineral supplies and demands and has developed 87 statements for specific commodities that assess the national position and problems for these metals, minerals, and mineral fuels. These statements, which constitute the chapters of this volume, are based on lire assumption that nearly till production and consumption of materials in the United States are to be by private individuals and organizations, in accordance with the Nation's devotion to a private-enterprise economy.

Jan 1, 1960

By Michael E. Berndt

Asbestos first became an issue to Minnesota?s iron industry when it was revealed that mineral fibers similar to those in Reserve Mining?s tailings were being found in drinking water for several communities that used Lake Superior as their primary water source. This discovery turned what had largely been an environmental court battle into a case concerning public health. The courts listened to much conflicting and uncertain scientific testimony on the size and distribution of the mineral fibers and on the potential health effects imposed by them. In April 1974, the plant was ordered to shut down by a federal judge but the company quickly appealed the decision. The appeals court granted a stay and ultimately ruled that the plant?s closure could not be justified based on the unknown health effects of the mineral fibers since the consequences of such an action would have immediate and severe social and economic impacts. The plant was allowed to continue operation, but ordered to abate emissions to air around the plant and to switch to a land-based tailings disposal system. Much of the scientific uncertainty and public concern over mineral fibers in Minnesota?s taconite industry remain today. ©2007 Elsevier Inc. All rights reserved. Keywords: Minnesota; Iron ore; Taconite; Asbestos; Amphibole; Reserve Mining; Tailings; Mesabi Iron Range

Jan 1, 2007

By N. L. Ayres

Tendon support systems have been successfully used to stabilize excavations. Tendon support systems are routinely designed using the axial load-bearing capacity of tendons, namely the tensile strength. To attain tensile strength the tendon must be loaded along its length, which often does not occur in practice. Tendons should optimally be installed at 90° to the surface of the excavation to achieve maximum penetration depth, yet this is often not physically or practically possible, and installations at angles less than 90° occur. Furthermore, the intersection of geological features within the rock mass frequently results in complex loading situations on tendons. The position and angle at which loading occurs results in different combinations of tensile and shear forces acting on the tendon, which can impact on the support performance of each unit and ultimately the whole system. All factors that influence the support system should be understood and taken into account to ensure a sound support design. Combination loading situations are further investigated and tested to obtain a better understanding of the mechanisms involved and the effects on tendon load-bearing capacity. Tendon support units were tested at different installation angles to establish the tendon performance, mechanical behaviour, and load capacity during these loading situations. The results and outcomes are aimed at providing rock engineers with additional data and improved understanding of how tendons could perform under certain conditions.

Jan 1, 2014

By M. Heger

February 2, 1999 marks a milestone in earth-moving technology at the San Miguel Lignite Mine. It was on that date that The North American Coal Corporation (NAC) took delivery of three Leica Dozer 2000 GPS grade control systems for use on its bulldozers. The primary reason for the purchase of these grade control systems was to prove that GPS technology could safely and economically be utilized on heavy equipment to assist operators in defining grades. If these properties were successfully demonstrated, the ultimate vision of the project was to expand the system to a point were GPS would become the primary means of providing grade control information to the mine’s heavy equipment operators. Twenty nine months and more than $500,000 later this vision was realized when the final bulldozer operating at the San Miguel Lignite Mine was equipped with Dozer 2000. Presently North American Coal has a total of nine Dozer 2000 GPS grade control systems at San Miguel providing cut and fill information to operators 24 hours a day. These grade control systems have allowed the San Miguel operation to increase safety, reduce costs, improve operator attitude, and better ensure environmental compliance. This article discusses both the nature of these benefits and some of the issues that had to be dealt with along the way.

Jan 1, 2002

By A. Schaum

On average, there are approximately 10 fatal haul truck accidents per year. The most common causes for haul truck accidents include mechanical problems, inadequate training and insufficient road/berm maintenance. Due to the frequency and magnitude of haul truck accidents, new training methods are being investigated. With the widespread availability of computers and new technology becoming more reasonably priced, the ability to incorporate computer-based training for miners is becoming more possible. It has been shown that computer-based training is just as effective in knowledge acquisition as traditional lectures, and computer-based training can lead to a significant increase in the retention of material (Williams and Zahed, 1996). Studies have also shown that more engaging training methods lead to more effective knowledge acquisition (Burke et al., 2006). A supplemental system for current and new miner training to address the common causes of fatal accidents was developed. The training system is a virtual preshift inspection of a haul truck, and it can train new haul truck operators to identify parts that look defective. The training will increase an operator?s ability to recognize problematic parts and correctly identify the corrective action needed. Increasing the quality of training by providing an engaging, simulated hands-on environment will lead to safer behaviors by trainees, which will ultimately lead to fewer accidents and fatalities.

Jan 1, 2008

By W. T. Wertman

A research program to aid development of better and more efficient methods for producing petroleum and increasing its ultimate recovery from underground formations is an integral part of the work of the Bureau of Mines on conservation of the Nation's natural resources. Economic, efficient production of recoverable oil and gas from a reservoir depends to a great extent upon the best and most accurate information that can be obtained from a study of the reservoir rock and its fluid contents. Information on oil and water saturation is pertinent and essential in wildcat, extension, and pool wells for good reservoir operations and prediction of performance. This report presents results of an investigation by the Bureau of Mines of core recovery and degree of drilling-fluid contamination occurring during cable-tool coring operations using oil-base mud. Representative core samples were obtained from 6 major oil-producing sands in 8 fields of West Virginia, Pennsylvania, and New York. Field-mixed, oil-base drilling mud was used for the first coring test, and lightweight, premixed oil-base mud, with an organic chloride tracer added, was used in coring eight other wells. Tracer analyses were made to determine contamination of core by drilling-fluid filtrate. Core analyses, including oil and water content and minimum interstitial water-saturation tests, were made on selected core samples to compare and evaluate water saturations determined by the two methods.

Jan 1, 1958

By Frank Parrish

History and performance data of 17 water-injection projects in Cooke and Grayson Counties in north Texas are presented for the purpose of studying and comparing operating practices and oil-recovery techniques. Water is injected into Strawn and Canyon sands of Pennsylvanian age. The principal formation flooded is the Strawn, which ranges in depth from 725 to 6,900 ft in the projects covered. Estimated ultimate recoveries range as follows: Primary, 22 to 494 bbl per acre ft; and secondary; 63 to 296 bbl per acre ft. These figures represent the following percentages of original oil in place: Primary, 10 to 46 pct; and secondary, 8 to 23 pct. Shallower projects; 725 to 1,500 ft in depth, had higher average primary and secondary recoveries than did deeper projects. Crude-oil gravity, which ranges from 20° to 45° API, was not relatable to yield of secondary recovery oil. Analysis of the data indicates that five-spot injection patterns will yield the highest percentage of oil remaining at start of flooding; that is, 28.8 pct for five-spot injection patterns, compared with 20.8 pct for line-drive patterns and 11.6 pct for random patterns. Waterflooding in this area appears to be very successful. Secondary recoveries of most projects are expected to nearly equal primary recoveries.

Jan 1, 1963

By Secretary of the Interior

"INTRODUCTION The Bureau of Mines Synthetic Liquid Fuels Program again forged ahead during 1952, and important technical advances led the way to improved methods of converting coal and oil shale into liquid fuels. Marking the eighth year of activities under this program, the pact 32 months brought a new domestic industry nearer realization.The increasing demand for gasoline and oil and the rising cost of finding new petroleum, coupled with America's growing dependence on imports and the unsettled international situation, have continued to emphasize the importance of the Bureau's Synthetic Liquid Fuels Program. Oil, the indispensable material of wartime, likewise has critical importance in peacetime, touching as it does the life of every individual. Supplementing petroleum with synthetic liquid fuels will not only conserve this Nation's petroleum reserves but also will bring into greater use its tremendous reserves of coal, as well as the vast deposits of oil shale for which no other practical use has yet been found.The Bureau of Mines Synthetic Liquid Fuels Program is one of the most important and far-reaching of the Government's research projects. Through development of commercial synthetic liquid fuels, the United States can obtain oil products from its great inland reserves of coal and oil shale to supplement petroleum in any quantity that may be necessary, consistent with economic and other requirements, such as national defense. The use of raw materials from such deposits would be of highest importance in wartime, when shipping lanes are menaced by the enemy. The Synthetic Liquid Fuels Program of the Bureau of Mines and research efforts of industry have advanced. American technology to the point where it is now possible to begin the design and construction of prototype plants. Certainly, significant improvements will be made as the program continues, but this prospect in no way alters the fact that the start of prototype plants should be encouraged. These plants, as the first step in the development of a synthetic fuels industry, would serve a threefold purpose:"

Jan 1, 1953

By J. H. East, D. Harrington

"INTRODUCTION Considerable interest has been shown in the prospective use of Diesel-powered haulage equipment in both coal and non-coal mines. Foreign technical magazines have devoted considerable space to discussions of the use of Diesel locomotives in European mines and some mention of it has been made in technical papers in the United States. The Bureau of Mines has extensively tested the gases produced in the exhaust of the Diesel engine under various atmospheres and conditions of use; it has established a schedule of tests for permissibility of Diesel engines for use in underground coal mines, including, gassy or dusty mines.This publication provides information as to the successful use of Diesel-powered equipment underground workings in the United States and Europe, briefly discusses the characteristics of some of the toxic gases found in the exhaust of Diesel engines, and points out that Diesel-powered equipment can be used with reasonable safety in underground minus if necessary and entirely feasible precautions are taken."

Apr 1, 1947

The purpose of this study is to formulate practical guidelines for active underground mining in close proximity to water bodies. This was accomplished through systematic completion of three phases of study: I) Collection and Documentation of Data; II) Application of Existing Guidelines to Case Histories of Previous Inundations; and III) Development of Recommended Guidelines for Underground Coal Mining Near Bodies of Water. Phase I of the study involved a worldwide data collection effort designed to obtain foreign and domestic guidelines for mining near water bodies, and accident records and case histories of accidental mine inundations. Within Phase II, existing guidelines were categorized and classified and then evaluated as to their effectiveness in precluding past inundations had they been in effect at the time of inrush. Advantages and disadvantages of existing guidelines were defined. Drawing on the broad data base established in previous study efforts, Phase III was directed at development of viable guidelines to promote the greatest possible coal extraction while precluding accidental mine inundation. Two levels of guidelines are presented; Level I Guidelines require little or no subsurface exploration on the part of the mine operator, while Level II Guidelines recommend various testing and investigative procedures to permit greatest possible mineral extraction. This report presents findings and conclusions of the study.

Jan 1, 1976

By Jr. Denton

This U.S. Bureau of Mines report presents the documentation for HEAPREC, a methodology for calculating reclamation performance bonds for cyanide heap leach operations. HEAPREC is a template developed for use with Lotus 1-2-33 release 2.01 or newer software. The report is presented in step-by-step "user's manual" format. Appendices contain detailed background and reference material on performance bonding, cyanide detoxification regulation, cyanide detoxification methods, general mine reclamation procedures, and an example bond calculation.

Jan 1, 1992

By A. Uiga

The U.S. Bureau of Mines funded a project which addressed objectives concerning irrigation of native plants and inoculation of native plants with vesicular-arbuscular mycorrhizal (VAM) fungi. The specific irrigation objectives were 1) to demonstrate the performance capabilities of solid-set irrigation for reclaimed mineland conditions, and 2) to demonstrate and evaluate three irrigation concepts under two separate water supply conditions. The VAM inoculations were to assess irrigation benefits in establishing VAM relationships for transplanted native species. Following the seasonal demonstration (May to September 1983) at 3 separate mine sites, conclusions were made that apply to the 6 state Western mining industry. The demonstration sites were located in Montana, Wyoming, and New Mexico. Positive conclusions were reached for 1) the use of soil moisture sampling with or without irrigation, and 2) the selection of solid-set sprinklers as the irrigation method. The conclusions about the irrigation concepts and strategy were mixed, due to the short-term (1 season) nature of the project. No conclusions could be reached for the VAM inoculations because the study time was too short.

Jan 1, 1984

When the Organic Act of 1910 established the Bureau of Mines within the Department of the Interior, the Bureau's programs involved only health and safety research and, education, and fuels testing. As the Federal Government's primary agency for research in minerals, the Bureau has expanded its scientific and technological investigations to mining, processing mineral substances, eliminating occupational health and safety hazards in the mineral industries, economic development, and resource conservation. Today, Bureau activities cover a broad spectrum of programs for meeting the diverse (and sometimes conflicting) needs of mineral industries, government, and the public. In the 1960's, the Bureau initiated programs to resolve environmental problems associated with past mining and mineral processing. In the 1970's, the energy crisis raised the national consciousness concerning our limited supplies of domestic mineral and fuel resources. Dependence on foreign sources of raw materials critical to our national economy and competition from other countries for these world supplies stimulated the need to conserve and use with intelligence the Nation's minerals, metals, and fuels.1

Jan 1, 1977

By Richard B. Moore

This bulletin presents a summary of available information regarding the sources of uranium, radium, and vanadium, the methods used in treating the ores, and the uses of the finished products. In particular the paper describes the ores found in the United States, giving especial attention to those characteristics of the ores and the conditions of their occurrence that affect mining and treatment. ACKNOWLEDGMENTS. In the preparation of this bulletin a number of persons rendered assistance by furnishing information and by making it possible for us to visit the carnotite deposits in western Colorado and eastern Utah at a time of the year when without this assistance it would have been difficult to obtain satisfactory results. We desire to express our thanks to the following persons: Henry Hall, W. L. Cummings, T. V. Curran, K. D. Hequembourg, David Taylor, H. C. Brown, Forbes Rickard, George W. Alsdorf, Dr. Herman Fleck, Orr J. Adams, C. S. Cherrington, Newt. Stewart, O. B. Willmarth, Angus Cameron, George A. Head, and Lorimer Bros.

Jan 1, 1913

By Wilmer McInnis

MOLYBDENUM, one of the more versatile alloying elements in modern metallurgy, was first isolated by Hjelm in 1782. The pure metal is silvery white and softer than steel. It melts at a higher temperature than all other metals except rhenium, tungsten, and tantalum. Molybdenum, a member of group V of the periodic table, chemically exhibits valences in stable compounds of 2, 3, 4, 5, and 6. It is a strong carbide-forming element, and much of its alloying effect in steel is imparted through the formation of carbides. Molybdenum occurs in nature only in combination with other elements. The most common occurence is molybdenite (MoS2), which is widely distributed throughout the world; the few known commercial deposits are the major sources of molybdenun1. The other commercially important mineral, wulfenite (PbMo04), was a major source of molybdenum in the United States during the early part of the 20th century, but with exploration and development of the world-famous Climax molybdenite deposit during the World War of 1914-18, molybdenite soon became the world's major source of molybdenum. In recent years, virtually no wulfenite has been mined. Many copper deposits contain minute percentages of molybdenite; and, since the inauguration during the early 1930's of the recovery of molybdenite as a byproduct of these deposits, they have been an important source of molybdenum.

Jan 1, 1957

By W. F. M. GOSS

For the purpose of procuring data that could be used in estimating the value of the briquetting process as applied to American fuels, the United States Geological Survey, in cooperation with other interests, began in 1904, at the Louisiana Purchase Exposition, certain experiments involving the production and use of bituminous-coal briquets. It installed at St. Louis, and later at Norfolk, machines for the manufacture of such briquets, and the output of these machines has been tested in locomotive service on several different railroads in comparison with natural fuels. An elaborate and carefully executed series of tests involving the use of natural coals and of briquets made from the same coal, previously crushed, was carried out on a locomotive mounted at the testing plant of the Pennsylvania Railroad Company at Altoona, Pa.; and some preliminary experiments involving the use of briquets in marine service were made in connection with one of the Government's torpedo boats. A description of these tests is presented herewith. The results sustain the following general conelusions: 1. The briquets made on the Government's machines have well withstood exposure to the weather. and have suffered but little deterioration from handling. 2. In all classes of service involved by the experiments, the use of briquets in the place of natural coal appears to have increased the evaporative efficiency of the boilers tested. 3. The smoke produced has in no test been more dense with the briquets than with coal; on the contrary, in most tests the smoke density is said to have been less when briquets were used. 4. The use of briquets increases the facility with which an even fire over the whole area of the grate may be maintained.

Jan 1, 1911

By Galen H. Clevenger, MARTINUS H. CARON

Although there are exceptions, oxidized silver ores containing the higher oxides of manganese are generally refractory to hydrometallurgical methods of treatment. When these ores are of high enough grade they can be smelted; indeed, some rather low-grade ores of this type have been smelted at a profit because of their fluxing value. In the past, when these ores could not be smelted, they either were not treated or were treated at low efficiency, generally by cyanidation. The need for thorough investigation of the problem was therefore evident for some time before the writers began their research. The problem of treating manganese-silver ores seems to have been recognized first about 35 years ago by C. W. Goodale in applying pan amalgamation at Tombstone, Ariz. He attributed the low extraction of silver to the fouling of the mercury by manganese rather than to the presence of a refractory compound of manganese and·silver. Although definite knowledge as to the cause of the poor extraction of silver was lacking, a more or less effective preliminary treatment, that is, a chloridizing roast, was applied. E. M. Hamilton, in 1909, was perhaps the first to define clearly the problem as it affects the cyanidation of silver ores and to suggest possible methods of preliminary treatment. Most of the work done in the interval between the appearance of Hamilton's paper and the assumption of the investigation by the authors was in the nature of routine tests covering suggestions already made rather than of research directed to a fundamental study of the problem. No practical application has so far been made of any of these proposed processes. The investigation described in this bulletin has proved that there s a refractory compound of manganese and silver-probably a manganite- insoluble in cyanide solution and other common solvents for silver. Although this compound has not been isolated from natural ores, it has been made synthetically, and shows all the characteristics of the natural product. Furthermore the authors have shown definitely that heating in air a relatively small amount of a silver compound with a large excess of silica (in the proportions ordinarily occurring in a commercial silver ore) renders

Jan 1, 1925