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By L. D. Gehi, A. W. Khair, M. Ahmad

This paper presents an analysis of the effect of the dynamics of bit wear on dust generation. Two surveys have been conducted in order to assess the mechanism and type of bit wear and to evaluate the impact of bit wear on the productivity of the continuous miners. Used bits were collected from the underground coal mines and these used bits were utilized in laboratory coal cutting. The effect of bit wear on dust generation has been quantified and its impacted on dust generation and ventilation system has been exemplified.

Jan 1, 1993

By I. Y. Bausov, L. G. Stolarczyk, R. E. Pillmore, A. J. Hillard, J. T. Duncan

"Prevalence of lung disease in younger miners surprised industry regulators, congressional members, researchers and black lung clinic staff members. Mitigation researcher focused on low-coal mining in the Appalachian regions until Miners Colfax Medical Center (MCMC) Black Lung Clinic examinations discovered 25 of 72 Wyoming coal miners with lung disease. To reverse recent upward trend in lung disease, research programatic have been directed at reducing exposure to respirable “float” dust. This paper suggests broadening the scope of research to include boundary detection in efforts to improve outcomes. Beginning with a better understanding of biochemistry of anaerobic bacteria methylation processes precipitating sulfur and heavy metals into thin seam boundary layers. Expanding research and development objective to focused on minimization of bit-pick crushing cone volume and preventing mining thin boundary coal layers and out-of-seam dilution. Black lung clinical evaluations of miner will confirm outcomes directed towards reduced occupational disease and smoke stack emissions. INTRODUCTION Miner exposer to bit-tip crushing cone volume, fragmentation and auger movement generated respirable “float” dust and boiler emissions are related science-technology –engineering-mathematics (STEM) problems. Formidable but not intractable problems are driven by oxidation of upper flood plain elements in the periodic table and biochemical metabolic presses occurring in coal basin. Because of burial compaction, quartz and trace heavy metals (Fe2+, Mg2+) are concentrated in thin seam boundary layers. By not cutting through thin boundary coal layer and out-of-seam into hard quartz containing rock layers, miner lung disease and smoke stack emissions are minimized. Cutting bit-pick elastic wave hydrodynamic principle force vectors in the coal layer must be aligned to minimize respirable dust generation, constrained by fragmentation size. Dust abatement by water spray and machine design are effective; but for, failure to address cutting cone dust volume generation and its distribution along run-of-mine (ROM) transportation systems the boiler. Real-time precision thickness measurements by integrated cutting drum (icDrum) sensor, machine man-interdiction from a dust free control room, is a cost effective way to prevents respirable dust exposure. The recommended STEM research and demonstration initiative addresses issues raised by discoveries of increased rate of lung disease discovered in young miners and concerns over emissions from coal-fired electric generation stations (Global Warming). In-mine demonstrations must be validated by on-site MCMC mobile Black Lung Clinic data acquisition and analysis."

Jan 1, 2016

By W. Gibson Jaworek

It has become apparent in recent years to everyone intimately concerned with the future of the American fuels industries that the growth in demand for energy has become a topic receiving considerable attention, and that investigators are leaning more and more toward a mathematical approach to deduce what pattern that growth will follow. Though coal has been included by necessity In all-studies of future energy markets, it has not been the subject of mathematical analysis or description as frequently as has been total energy or some of the other fuels, particularly petroleum, It is the intent in this particular paper, to subject bituminous coal consumption to a preliminary mathematical scrutiny which can lead to a more logical estimation of the general level of bituminous coal consumption for the next decade, as well as formulating an approach toward describing how coal consumption may vary as the result of the annual variations in activity in the United States, economy, The approach utilized is more sophisticated than the mere projection of the historical trend of bituminous coal consumption. Such a projection would lead to a continuation of the recent decline, indicating that coal consumption would reach zero some thirty years from now. On the other hand, the mathematical analysis described here is a relatively simple, straightforward approach and- is not intended to represent the-ultimate in mathematical economic analysis as now practiced, It is hoped that this will contribute to our knowledge of bituminous coal markets. Even more, it is hoped that it will help arouse a greater interestin utilizing mathematical and statistical analysis when studying the bituminous coal industry. - Since this is a preliminary study, comments and criticisms are anticipated.

Jan 1, 1960

By John A. L. Campbell

Surface dependent processes, such as froth flotation and flocculation, are important or potentially important techniques for combating some of the current major problems in coal preparation. In order to correctly apply or imporve a surface dependent process, it is of paramount importance to understand the interfacial phenomenon, especially the double layer properties, exhibited by the solid. The specific objective of this research was to determine the properties of the bituminous coal/liquid interface by an electrokinetic method, streaming potential, and to relate the findings, wherever possible, to the existing unit operations of froth flotation and flocculation. The electrokinetic properties of both the whole coal and its lithotypes were investigated. As part of the total investigation, the role played in the double layer by the reagents commonly employed in the surface dependent process was also established (1). These data will be presented at a latter date.

Jan 1, 1969

By Theodore Nagel

Fuel-oil, natural gas and coke oven gas, producing the higher temperatures of open-hearth current practice, have been gradually displacing producer gas the lowest cost fuel for open hearth operations. The lower temperatures of combustion products from producer gas is caused by nitrogen dilution. Practical Application of Combustion Thermochemistry One pound of carbon burned to CO produces 3,960 B.T.U. and one pound of carbon burned to C02 produces 14,140 B.T.U. The second unit of oxygen uniting-with gasified car-bon (-CO) produces (14,140 - 3,960) 10,180 B.T.U. which is;(10,180 - 3,960) 6,220 B.T.U. more heat than produced by the first, unit of oxygen forming CO by uniting with solid carbon. A review of the relative combustion heating values of commercial gaseous fuels reveals CO requires a minimum of air for combustion, and because of minimum nitrogen dilution and the high thermal release from CO higher temperature combustion products are produced from CO than from natural gas or from coke-oven gas under similar combustion conditions. Inert nitrogen diluent lowers the calorific value of fuel gas and its diluting effect is cumulative in lowering the temperature of the products of total, combustion. It is not only logical but, practical in partial combustion, converting bituminous coal to gas, to generate the gas, with reduced nitrogen dilution.

Jan 1, 1936

By Theodore Nagel

Fuel-oil, natural gas and coke oven gas, producing the higher temperatures of open-hearth current practice, have been gradually displacing producer gas the lowest cost fuel for open hearth operations. The lower temperatures of combusts on products from producer gas is caused by nitrogen dilution. Practical Application of Combustion Thermochemistry One pound of carbon burned to CO produces 3,960 B.T.U. and one pound of carbon burned to C02 produces 14,140 B.T.U. The second unit of oxygen uniting with gasified carbon (CO) produces (14,140 - 3,960) 10,180 B.T.U. which is (10,180 - 3,960) 6,220 B.T.U. more heat than produced by the first unit of oxygen forming CO by uniting with solid carbon. A review of the relative combustion heating values of commercial gaseous fuels reveals CO requires a minimum of air for combustion and because of minimum nitrogen dilution and the high thermal release from CO higher temperature combustion products are produced from CO than from natural gas or from coke-oven gas under similar combustion conditions. Inert nitrogen diluent lowers the calorific value of fuel gas and its diluting effect is cumulative in lowering the temperature of the products of total combustion. It is not only logical but practical in partial combustion, converting bituminous coal to gas, to generate the gas with reduced nitrogen dilution.

Jan 1, 1936

By D. P. Morton

SINCE 1023, which closed the speculative era in the bituminous coal fields of the United States, there have been wide annual fluctuations in the national production of bituminous coal. These changes in annual output have been variously attributed to: (I) increased competition from petroleum products, natural gas and hydroelectric power; (2) lower unit consumption of coal; and (3) fluctuations in the general business level. The purpose of this paper is to measure, from a practical standpoint, the net effect upon the annual trend of bituminous coal production, and to give those who are interested a basis for estimating in advance the probable output of bituminous coal. It can readily be shown that changes in the level of general business affect the national production of bituminous coal more than does any other factor. Therefore it is necessary to use some standard measure of the relative business level for purposes of comparison. The Federal Reserve Board Index of Industrial Production offers the basis for such a measure.' This Index, a weighted composite of 81 different series, rests upon the averages of the years 1935 to 1939 as loo, and is presented graphically in Fig. I. Even a cursory examination of the chart will indicate a definite uptrend for industrial production over a period of years. This uptrend is due to at least two factors: (I) an actual increase in national population, and (2) a probable increase in the per capita consumption of goods. This means that there is no such thing as a fixed Normal, rather Normal is a variable, tending to increase from year to year. In order to measure the amount of annual increase in normal, the Index of Industrial Production must be studied in relation to its major components, Durable Goods and Nondurable Goods. Durable Goods are those made from the lasting materials such as iron, steel, other metals, lumber, stone, cement, clay, glass. Nondurable Goods are those for early consumption, such as foods, textiles, tobacco, chemicals, paper, gasoline, and goods made of leather and rubber. The purchase of Durable Goods may be postponed, but Nondurable Goods must be purchased currently unless the standard of living is lowered. The Federal Reserve Indexes of durable and nondurable goods are shown graphically, 1920 to 1939, on Fig. 2 (pp. 764-765 of ref. I). It is apparent that fluctuations in the production of nondurable goods are not nearly so wide as in the production of durable goods, and that the curve of Industrial Production (Fig. I) would fall between the two curves on Fig. 2. It would, however, seem logical that both curves should follow the same long-term trend, or that over a period of two to three decades the relative proportion of durable and nondurable goods, in periods of normal production, should he the same. It is neces-

Jan 1, 1941

By R McIlwraith, B Breul

"This paper discusses the successful use of bituminous geomembranes (BGMs) in mining applications since their development in 1974. It explains and illustrates the structure of a BGM composite, which is a geomembrane manufactured by impregnating a polyester geotextile with a compound of bitumen, elastomer and filler. Examples of applications of BGMs in the mining industry are also presented in the following contexts.Storage of solid waste: storage of mining waste at mines in Canada heap leach pads in France, Peru, Chile and Turkey at the base of a mining waste landfill in Brazil capping of solid mining waste in Chile and Canada temporary capping of mining stockpiles in Australia (with possible reuse of the BGM for other works).Examples of the application of BGMs for the storage of liquid waste in mining containment reservoirs in Canada, Guatemala and Peru will also be given.For each example given, reasons are supplied that supported the choice of BGMs by the clients and consultants, drawn from the following advantages of the BGM:BGMs have excellent puncture strength, due to the internal polyester reinforcement, as well as excellent ultraviolet resistance. This often eliminates the need for a cushion geotextile or cover soil over the BGM.BGMs have a very long life expectancy, in excess of 300 years, in subsoil conditions (Breul et al, 2004).BGMs can be installed in very harsh climatic conditions. They are suitable for high wind environments as their heavy mass per square metre makes them resistant to wind uplift. The low coefficient of thermal expansion means that BGMs are suitable for installation in mines where very low or very high temperatures are expected. This reduces construction delays and allows for a quicker use of the mining facility.The fact that the BGM can be installed by the mine’s own workforce, after appropriate training from the BGM manufacturer, allows for a more flexible construction sequence on the mine.Ability of the BGM to connect to other materials such as concrete, steel, rock and other geomembranes that may be on the mine site.The technical advantages of a BGM enabled the engineering consultants to prepare solutions for their mining clients that had a lower environmental risk, had a faster completion schedule and were overall a cheaper option than with a polymeric geomembrane.CITATION:Breul, B and McIlwraith, R, 2015. Bituminous geomembranes in mine construction, in Proceedings Tailings and Mine Waste Management for the 21st Century, pp 289–296 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 27, 2015

By John M. Bostwick

Bitumen is a general term for a group of materials composed of mixtures of hydrocarbons that are fusible and soluble in carbon disulfide. Included in the group are petroleum, asphalts, asphaltites, and mineral waxes. Asphalt is a dark-colored, cementitious solid or semisolid, which generally softens on heating and resumes a more viscous or solid state when cooled (personal communication). It is found in native form in fissures and pore spaces in rocks and as lakes. It is also obtained from the residues produced in petroleum refining. Asphaltites are black, naturally occurring solid bitumens. They are generally shiny and break with a conchoidal fracture. Common asphaltites are gilsonite (uintahite), grahamite, and glance pitch. Mineral waxes are solid or semisolid, relatively nonvolatile bitumens of various colors, having an unctuous feel and waxy luster. Of the native waxes, ozokerite is the best known. Montan wax is also classed as a natural wax, although it never occurs in the pure state and must be extracted from lignite or cannel coal (Ladoo, 1920). Mineral waxes may also be obtained by pyroprocessing of petroleum, lignite, and peat. Pyrobitumens are dark-colored, solid hydro- carbons that are infusible and relatively insoluble in carbon disulfide. They are so-called because they will yield liquid and gaseous hydrocarbons only when heated. Asphaltic pyrobitumens are defined as "substantially free of oxygenated bodies" and include wurtzilite (elaterite), albertite, and impsonite (Thrush, 1968). Nonasphaltic pyrobitumens contain oxygenated bodies; examples are coal and peat. The nonasphaltic type will not be discussed further. Petroleum Asphalts Asphalts refined from crude petroleum have almost completely replaced the native types. Refineries can produce asphalts in every desirable grade more economically and in greater quantity than the native types and with a variety of properties that meet the requirements of the various manufacturers using them. For all practical purposes, it is estimated that more than 95% of the asphalts consumed in the United States are refined from crude petroleum (private communication).

Jan 1, 1975

By John M. Bostwick, James C. Bradbury

Bitumen is a general term for a group of materials composed of mixtures of hydrocarbons that are fusible and soluble in carbon disulfide. Included in the group are petroleum, asphalts, asphaltites, and mineral waxes. Asphalt is a dark-colored, cementitious solid or semisolid, which generally softens on heating and resumes a more viscous or solid state when cooled. It is found in native form in fissures and pore spaces in rocks and as lakes. It is also obtained from the residues produced in petroleum refining. Asphaltites are black, naturally occurring solid bitumens. They are generally shiny and break with a conchoidal fracture. Common asphaltites are gilsonite (uintahite), grahamite, and glance pitch. Mineral waxes are solid or semisolid, relatively nonvolatile bitumens of various colors, having an unctuous feel and waxy luster, Of the native waxes, ozokerite is the best known. Montan wax is also classed as a natural wax, although it never occurs in the pure state and must be extracted from lignite or cannel coal (Ladoo, 1920). Mineral waxes may also be obtained by pyroprocessing of petroleum, lignite, and peat. Pyrobitumens are dark-colored, solid hydrocarbons that are infusible and relatively insoluble in carbon disulfide. They are so-called because they will yield liquid and gaseous hydrocarbons only when heated. Asphaltic pyrobitumens are defined as "substantially free of oxygenated bodies" and include wurtzilite (elaterite), albertite, and impsonite (Thrush, 1968). Nonasphaltic pyrobitumens contain oxygenated bodies; examples are coal and peat. The nonasphaltic type will not be discussed further. Petroleum Asphalts Asphalts refined from crude petroleum have almost completely replaced the native types. Refineries can produce asphalts in every desirable grade more economically and in greater quantity than the native types and with a variety of properties that meet the requirements of the various manufacturers using them. For all practical purposes, it is estimated that more than 95% of the asphalts consumed in the United States are refined from crude petroleum (private communication). Native Asphalts Native asphalts are dark brown or black, semisolid or solid substances that, in theory, formed by slow, natural fractionation of crude petroleum at or near the surface of the earth (Goulston, 1938). They are colloidal systems of high molecular weight components dispersed in a medium consisting of low molecular weight components (Pracy, 1954). Native asphalts may occur as lakes, as impregnations of rock (rock asphalt) or as deposits consisting of mixtures of natural asphalt and mineral matter in various proportions (Stern, 1960). Practical use of native asphalt dates to about 3000 B.C. It was mined from surface pits or lakes and used, then as now, for masonry mortar, waterproofing aqueducts and tunnels, binders for road construction, and as an article of commerce (Miller, 1938). Generally the native asphalts find little commercial use today except where they are geographically abundant, easily mined and transported, or have specific or special application. Petroleum-refined asphalt is produced by unusually economical techniques and is much less costly to use. The largest and best known of the lake deposits is that on the Island of Trinidad, where the lake covers an area of 114 acres and is 285 ft deep at its center (Stem, 1960). The lake asphalt is refined by heating to evaporate in-

Jan 1, 1983

By S. C. Ellis

THE bituminous sand of northern Alberta has already an extensive literature, and most of the reports dealing with the subject are still available (see Selected Bibliography at end of paper). A phenomenon so striking and, as regards its extent, so unique, as the deposit in the vicinity of McMurray settlement could not fail to attract the notice of the early explorers, and we find references to it as far back as the latter part of the eighteenth century. However, scarcely a thought had been bestowed upon the possible economic value of minerals in the the remote northern parts of Canada before the second decade of the present century, and practically no detailed mapping had been done north of the town of Athabaska. The late Wm. Ogilvie made a track survey of Athabaska river in 1884, and surveys of certain lines-including the 23rd base line-had been completed by 1911. Between this base line and lake Athabaska, nothing had been attempted. Actually, no definite information at all was available regarding the character and extent of the bituminous sand when, in the earl y summer of 1913, a reconnaissance party set out from Athabaska for McMurray. At that period, the journey was made in summer by scow or canoe. No telegraph line had been laid, and a casual mail service by canoe or dog team once in three months formed the only means of communication with the outside world. The investigation has begun by the Mines Branch was continued during several subsequent years. The sand deposits were studied and sampled, the bi rumen was extracted from the sand and studied chemically and physically, and the economic significance of the deposit was given exhaustive study.

Jan 1, 1937

By Brahm D. Prasad

As in other mineral deposits, variation in bitumen saturation, thickness of ore and discard occurs throughout Alberta's Athabasca Oil Sands deposit. The economic stripping ratio developed here to determine surface mineable limits takes into account capital and operating costs, crude oil prices, quality of ore, thickness of overburden, and thickness of inter-ore waste. The surface mining systems employed to remove bituminous sands (oil sands) from huge mines at depths of 60-70m use gigantic draglines, bucket wheel excavators and reclaimers, and large mobile equipment.

Jan 1, 1982

The deposit was discovered during systematic reconstruction of the geological history of glacial overburden, which averages 6 m in thickness over 80% of Sweden, by geochemical sampling and searching for small grains of eroded bedrock. The gold is mainly concentrated in and around high-grade quartz veins within a broad shear zone, though the correlation coefficient between quartz and gold in samples is not significant. Production from two pits, now connected, in the Central and Eastern orebodies has increased steadily from 1 238 kg Au in 1989 to 2 120 kg in 1994, the highest in Europe. The mine has adapted and improved its mining methods to achieve significant productivity increases and cost reductions. Most of the improvements have been achieved through a better understanding of the controls on mineralisation and of the implications of those controls for selective mining. Geostatistics has played an important role in the quantification of grade variability and gold occurrence. Better blasting and loading techniques have improved selectivity, grade control has been enhanced by a grade-control drilling programme, and significant improvements in mineral processing have been made

Dec 1, 1995

By Raja V. Rarnani, Robert L. Frantz

"Mining is one of the oldest of human occupations. The awareness of occupational illnesses associated with mining, even in ancient times, is evident from the writings of Hippocrates (460-370 BC), Pliny and Elder (AD 23-79), and Galen (AD 131-210). Georgius Agricola (1494-1535), in his De Re Metallica, refers to the diseases of miners and the need for their control through good planning and operating practices and responsible management (Schwerha, 1989). Coal workers' pneumoconiosis (CWP), often called Black Lung disease, is an occupational disease which results from inhalation of coal mine dust which usually contains relatively small amounts of free crystalline silica.A pneumoconiosis is best defined as the accumulation of dust in the lungs and the tissue's reaction to its presence [Lapp and Castranova, 1993]. Silicosis is the name given to the fibrotic disease of the lungs caused by the inhalation of dust containing silicon dioxide, primarily in the free crystalline form. Silicosis is the older and more well known of these mineral pneumoconioses. In contrast, CWP was not recognized as different from silicosis until the pivotal work of Collis and Gilchrist [1928].The U.S. Bureau of Mines (USBM) still regards worker exposure to respirable aerosols in mines as the most serious health problem in mining [USBM, 1994]. The National Institute of Occupational Safety and Health (NIOSH) is considering recommending a reduction in the standard for occupational exposure to respirable coal mine dust from 2 mg/m3 to 1 mg/m3 [NIOSH, 1993]. The Mine Safety and Health Administration (MSHA) may require new criterion for sampling procedures in the mine that would evaluate the ambient dust concentration in the mine atmosphere based on a single sample, instead of the current practice of averaging five samples (MSHA, 1992; Ramat* 1993). Several high-production longwall mining faces currently have extreme difficulty meeting the existing dust standards, and some already operate at reduced production levels to achieve mandated levels [USBM, 1993]. The importance of adequately protecting the miners from high concentrations of coal mine dust, as well as of reducing the incidence and severity of the Black Lung disease, cannot be overemphasized. The importance stems, first and foremost, from the humanitarian viewpoint and, second, from the perspective of the overall welfare of the coal industry.The histopathologic hallmark of CWP is the coal macule (Balaan, Weber and Banks, 1993). Autopsy or open lung biopsy reveals the coal macule to be an amorphous mass of coal particles, dust-laden pulmonary macrophages, reticulin, and collagen. No pathognomonic signs or symptoms identify workers with CWP. A CWP diagnosis requires that the worker experienced the appropriate dust-exposure setting (e.g., underground coal mining) and duration (usually 10 years or more) and, has the characteristic chest radiograph. Based upon the International Labour Organization (ILO, 1980) international classification, pathologists and radiologists have established case definitions for characterizing the pathology and the appearance of CWP on chest radiography (Weeks, 1993). CWP appears in two principal forms: simple, with small opacities, and complicated, with opacities larger than 10 mm in diameter. For all practical purposes, diagnosis of CWP in the living miner is wholly dependent upon the chest radiograph interpretation."

Jan 1, 1995

By M. M. Rajkovich, L. Adams, J. J. Zaluski, S. Gardner

In 1998, a group called Kentuckians for the Commonwealth filed an Administrative Petition with the Kentucky Natural Resources and Environmental Protection Cabinet to designate 8,903± hm2 (22,000± acres) on Black Mountain, which contains the state's highest point, as unsuitable for mining. A fast track legislative process was triggered that could have "taken" 91 Mt (100 million st) of coal reserves or, in the alternative, imposed severe restrictions on mining. Even with all parties represented by reasonable individuals, this process can be extremely cumbersome and expensive. The legal and technical preparation for this unusual hearing process as well as issues and strategies of the negotiated resolution are reviewed

Jan 1, 2002

By M. M. Rajkovich, L. Adams, J. J. Zaluski, S. Gardner

In 1998, Kentuckians for the Commonwealth filed an Administrative Petition with the Kentucky Natural Resources and Environmental Protection Cabinet to designate 8,903 +/- hectares (22,000 +/- acres) on Black Mountain, which contains the state’s highest point, as unsuitable for mining. A fast track legislative process was triggered which could have "taken"100 million tons of coal reserves or, in the alternative, imposed severe restrictions on mining. Even with all parties represented by reasonable individuals, this process can be extremely cumbersome and expensive. The legal and technical preparation for this unusual hearing process as well as issues and strategies of the negotiated resolution are reviewed.

Jan 1, 2000

By H Wright

Black Rock Cave (BRC) is a sublevel cave which was developed in 2018–2020 and has been in production since November 2020. BRC is part of the Mount Isa Mines complex and extracts a leached orebody comprising of high-grade chalcocite ore, situated below the historic Black Rock Open Cut workings. The mine is owned by Mount Isa Mines and operated under contract with PYBAR Mining Services. In 2021 a number of rockfalls occurred throughout the mine and were increasing in frequency. This culminated in a major rockfall on the decline in June 2021, after which the decision was made to withdraw all persons from the mine, initiate rehabilitation and conduct further investigations to deduce a safe method to provide long-term support. The rockfall investigations have shown that the corrosive nature of the highly leached rock mass can consume a split set in less than 18 months. A review of potential corrosion resistant ground support methods concluded that steel split sets have a safe lifespan of six months at BRC, and that all workings must have corrosion resistant support installed prior to exceeding the safe life of the friction bolts. The review recommended the use of 4 m cable bolts as the most suitable method of corrosion resistant support. This new support system, and the requirement to rehabilitate all mine workings within the leached orebody, had an impact to the schedule and an effect on both equipment and manning levels at BRC. Accelerated jumbo rehab allowed access to the production levels within two months of the rockfall. Cable bolting then followed the jumbo bolting in all leached areas. The direct impact has been ten months of reduced production, due to night shift closures of the decline to enable cable bolting. The impact to the mine has been minimised by the small flexible team that enabled the mine plan to change rapidly and often to accommodate the challenging conditions. In less than two months from the rockfall event, production had resumed. Within ten months of concluding that the mine required; full rehabilitation, a new support system and a full re-schedule, normal mining operations had restarted, with pre-event productions rates being achieved.

Mar 29, 2023

By Fan Delian, Ye Jie, Lui Tiebing

The lower and the upper parts of the Doushantuo Fonnation, Hubei Province, China, contain silicate-type K-rich beds (illite and feldspar), and intraclastic phosphorites, as well as Ag-V and V deposits in a "Black Shale Series". The K-rich beds fonned in an anoxic basin whereas the phosphorites fonned in a more oxic and higher energy depositional environment. The Black Shale Series occurs in the lower and upper parts of the Doushantuo Fonnation; that in the upper part consists of black illite shale and dark gray dolostone, and contains Se-rich Ag and V deposits. These deposits are of more industrial significance than the previously discovered Ni-Mo polyelement sulfide deposits which occur in the Lower Cambrian Black Shales Series of South China. Studies of lithotype, sedimentary sequence, and geochemistry of the Doushantuo Fonnation have led to more attention being focused on the uppennost Black Shale Series and its Ag-V and V deposits. There are three ore types: black, Ag-V-rich, illite shale; black, V-rich, illite shale; and dark gray, Ag-Vrich, fmely crystalline dolostone. The first two ore types contain 3070 to 5% Corg and the last, 1.25%. The Ag-bearing minerals are naumannite, argyrodite, aguilarite, acanthite, and native silver that occur as inclusions in pyrite associated with barite. Vanadium substitutes for AI in illite and is also related to organic-matter contents. Because (1) the pre-Sinian Kongling Group contains one to three times greater than the Clark Ag value; (2) black, illite shale has a negative Ce anomaly; and (3) there are large occurrences of black, K-rich, tuffaceous, fme siltstone, the sources of Ag are thought to include subaerial and submarine volcanic materials. It is proposed that Ag, V, and Se were absorbed by clay particles and organic matter during syngenetic deposition in an anoxic environment; Ag subsequently was reconcentrated into sulfides and selenides, whereas V was incorporated structurally into illite during early and late diagenesis. These types of Black Shale Series-hosted Ag-V and V deposits are, therefore, considered to be sedimentary-diagenetic in origin.

Jan 1, 1992

By Robert L. Martin, Brian W. Stump, David P. Anderson, David Gross

In an attempt to better understand the impact that large mining shots will have on verifying compliance with the international, worldwide, Comprehensive Test Ban Treaty (CTBT, no nuclear explosion tests), a series of seismic and videographic experiments has been conducted during the past two years at the Black Thunder Coal Mine. Personnel from the mine and Los Alamos National Laboratory have cooperated closely to design and perform experiments to produce results with mutual benefit to both organizations. This paper will summarize our activities, highlighting the unique results of each.

Jan 1, 1997

By Hugh W. Evans

Many reports and papers have been delivered on projects under construction or already in operation, but we believe there are few that have been written about projects yet to be built specifically dealing with advanced mine and environmental planning. This paper describes such planning for Atlantic Richfield Company's Black Thunder mine. Project planning is a cyclic phenomenom involving four broadly overlapping planning steps (Figure 1). The demands of the public include needs that can be satisfied through planned resource development. Using a base of information that partly exists and must in part be gathered and updated, the preplanned development can be, evaluated. The evaluation process, with built-in environmental constraints leads to an implementation procedure. Implementation results in the development, including the release of the affected area to other public demands that follow.

Jan 1, 1975