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By Ronald J. Thomas

Prior to 1974, bauxite-producing countries were poorly informed about important aspects of the bauxite/alumina/aluminium industry. This placed them at a disadvantage in negotiations over the development of the industry with interested parties. Since the formation of IBA, its member governments have acquired a fuller awareness of the structure and operation of the industry. The role of IBA is to enlarge the relevant information base of member governments, to act as a forum for the exchange of information on the industry and to form a focal point for multilateral discussions on problems in the industry with corporate interests and with governments of consuming countries.

Jan 1, 1984

By Peter J. Szabo

In 1980, a caravan of representatives of Japanese trading companies debarked on the shores of the United States bearing gifts of watches, electronic games, and radios. In early 1983, we find in a parking lot of a major U.S. coal company, a haggard general manager of marketing returning to the Orient with a box under his arm of trinkets of his own; cross pens with company logos, alarm clocks, etc. The tables have turned, but our fellow sitting in a jet plane over the Pacific Ocean had only to heed the warning of the famous 19th Century poet well familiar with the ways of the Far East. Kipling said; "And the End of the Fight is a tombstone white and with the name of the late deceased, And the epitaph drear, a fool lies here who tried to hustle the East."

Jan 1, 1984

By H. Ikeda

INTRODUCTION [Slide 1] The Role of the MMAJ Ladies & Gentlemen, it is a pleasure for me to be able to make a speech at this SME annual meeting, representing the Metal Mining Agency of Japan. [Slide 2] Today’s Topics In my presentation today, I would like to divide my topics into four parts. First of all, I would like to describe the current situation of Japanese non-ferrous metal mining and mineral processing industries in Japan. Secondly, the supply and demand of non-ferrous metals in Japan. Thirdly, I would like to spare some minutes on the overview of overseas development by Japanese mining companies. Finally, since some people may not be sure what the Metal Mining Agency is or what this Agency, I would like to briefly introduce the Metal Mining Agency of Japan.

Jan 1, 2001

By M. Niec

Poland lies at the junction of three geologic provinces: the East European Precambrian platform, the Middle European Paleozoic platform, and the Alpine orogenic belt comprising the Carpathian Mountains. However most of the rocks that contain mineral deposits and many of the recently explored and mined deposits are commonly hidden under thick overburden, sometimes up to over 500 m thick. The discovery of these mineral deposits was due to the combination of geologists talents for inference and the keen interpretation of geophysical data ultimately tested by drilling. Examples of such use of the state-of-the-art geology include the following: 1. Sedimentologic and paleogeographic reconstructions led to the discovery of 8.8 Gt of bituminous coal under 500 m of Jurassic and Cretaceous cover in the Lublin basin, 2. Tectonic and paleogeografic data suggested a potential for discovery of burried Upper Permian copper de-posits on the Foresudetic monocline; subsequent exploration discovered 75 Mt of copper and 0,17 Mt of silver, 3. Geological interpretation of gravity and magnetic da-ta combined with sedimentologic data and regional subsur-face geology resulted in the location of 1.3 Gt of Fe-Ti-V ore in the Precambrian basement of northeastern Poland under -500 m of cover 4. A combination of metallogenic theory and geological interpretation of regional geophysical mapping led to the discovery of Caledonian-Hercynian granites and grano-diorites with accompanying porphyry-type Mo-W-Cu ores below 300 m cover on the northeastern border of the Upper Silesian coal basin 5. Tectonic reconstructions based on gravity and seismic data combined with theory on the origin of native sulfur led to the discovery of 1.0 Gt of native sulfur under cover up to 300 m thick. Five deposits were found at the northern margin of the Carpathian Foredeep. The other deposits found include lignite, polyhalite, lead-zinc ores.

Jan 1, 1996

By Brent Chamberlain

MARY KORPI: As has been typical today, our next speaker is filling in for one of his co-workers. Scott Lawson will be discussing "The Role of the Supervisor in Mining Operations" written by Brent Chamberlain of Independence Mining Corporation. Scott has more than 25 years in human resources management in the mining industry. He has worked in surface and underground mining environments in both precious and base metal mines. A graduate of Ohio University, Scott is currently manager of human resources at the Independence Mining Company's Cripple Creek and Victor Gold Mining operation located in Victor, Colorado. The only direction that I received from Scott was that he has to leave by 11:45 a.m. as he has a tee-off time with his boss at 1:00 p.m. Thank you to Scott for filling in today.

Jan 1, 1998

By Raymond F. Mikesell

This paper evaluates the contributions of "third parties" to surplus capacity in the world metals industries in the 1980s. Special attention is given to the role of international development agencies, such as the World Bank, that have made project loans to state mining enterprises. The paper also reviews the contributions to surplus capacity of the International Monetary Fund and evaluates the large volume of credits from commercial banks to developing countries. Although the credits to Third World countries during the 1970s facilitated the expansion of mining capacity in those countries, no one source of financing can be held responsible for a significant portion of the expansion.

Jan 1, 1989

By B. Denby

Recent advances in Virtual Reality (VR) technology have resulted in major opportunities to improve safety training of mine workers, supervisors and managers. The hazardous nature of both surface and underground environments limits the type of safety training that can be carried out. VR offers the potential to expose mine personnel to hazardous situations in a safe, highly visual and interactive manner. Customized simulations of mine layouts, dynamic operations and mine environment can be set up and mine personnel can be allowed to move around the virtual mine, making decisions at key points. The consequences of both correct and incorrect decisions can be immediately fed back to the trainee.

Jan 1, 1998

By R. H. Clarke

"INTRODUCTION Characterization of waste rock is frequently an oversight in mine planning which can contribute to significant delay in permitting and ultimately development. Thorough waste rock characterization is now a prerequisite to developing operating and closure plans acceptable to regulators and the public. BACKGROUND A long history of mine development has placed virtually all focus on the economic extraction and beneficiation of ore materials, while waste rock characterization and management received substantially less attention and consideration. Inadequate waste rock characterization has contributed to planning and management practices that are having unintended and unforeseen impacts to surface and groundwater, and in some cases lead to significant long term closure liability. In response, the regulatory community has developed guidelines for performing waste rock characterization during the pre- mine permitting process that in some cases seem onerous (BLM, 2013). Additionally, where a project proponent has not met these guidelines or results have been deemed “inadequate”, the Nevada Division of Environmental Protection and Bureau of Land Management (regulatory agencies) will only issue operating permits with rigid management practices to address the uncertainty, including requirements for lining waste rock facilities. WASTE ROCK CHARACTERIZATION FOR NEVADA PROJECTS Newmont Mining Corporation (Newmont) operations in Nevada approaches waste rock characterization like ore characterization, as it requires a similar investment of time, funding and attention to detail in order to pass public and regulatory scrutiny. Newmont follows a tiered approach to characterization that creates three over-lapping data sets representing an “escalation” in analysis at each tier, an approach that has thus far gained regulatory approval. “Tier 1” waste rock characterization for most Newmont projects begins with exploration drilling which follows internal standards and procedures. 20-foot composite samples are prepared from all drilling and analyzed for multiple trace elements using inductively coupled plasma mass spectrometry (ICP-MS) methods and for acid-base characterization using method ASTM-E1915. If the exploration program is successful and further resource or reserve development is recommended, the Tier 1 data are used to prepare a Waste Rock Characterization Plan (Plan) that will be presented to regulatory agencies as a part of baseline project characterization."

Jan 1, 2015

By Mark R. Stanton

Geochemical and mineralogical analyses of 46 samples from six drill cores in the Mayday mine pile near Silverton, Colorado, demonstrate wide variability in trace metal contents with spatial location. This variability results from the original geochemical composition of mined rocks, mixing of ore and non- ore rocks during emplacement of the pile, and weathering since rocks were placed in the pile. Weathering reactions are controlled by factors such as pile thickness (depth), water availability, microbial activity, and mineral dissolution and formation kinetics. These factors result in variable redistributions of trace metals from primary (ore) to secondary (weathering products) minerals within each core.

Jan 1, 2000

By Donald V. Fites

The evolution of open-pit mining has been rapid during the last two decades. The development of larger, more productive and efficient equipment has been one of the key factors in this open-pit advancement. Selection of the proper equipment and its correct usage is paramount to successful operation while maximizing return on investment. The quantity of material being moved prior to mining the saleable product is increasing at a significant rate. For example, at a southwestern copper mine more than two hundred million tons of over- burden have been removed prior to exposing an ore which contains less than 1% copper. A recent survey of twenty-three Western Hemisphere copper mines reveals the average strippingratio was 2.2:l with a range of 0.9-8.5:l. In the face of increased mineral demand, the resulting technological developments and rising overburden to ore ratios, many open-pit mines now use totally different concepts for the removal of ore and overburden. An increasing number of these concepts now being installed include wheel tractor scrapers as a major part of the material handling system for unconsolidated overburden removal. To say scrapers move only unconsolidated overburden is incorrect. On the contrary, ripped phosphate rock, copper ore, iron ore, and moderately consolidated overburden are also being moved by scrapers in various areas of the world. As reported in the Minerals Year- book, however, about one-half of the material moved in metal and non-metal mines is never drilled and blasted or broken by other means. We will, therefore, in this paper, concentrate on the role of wheel tractor scrapers in unconsolidated overburden; the area of greatest usage.

Jan 1, 1969

By Bernard P, Lhoumaud E, Gunzburger Y, Conin M, De Santis F, Kinscher J

Seismic repeaters are commonly observed in natural fault zones dominated by slow aseismic motion. The corresponding seismic signal, characterized by highly similar wave forms, is usually interpreted as the repeating ruptures of locked asperities on fault planes (“patches of higher roughness”), loaded by a-seismically slipping areas (“creeping areas”) (Chen & Lapusta 2009; Bourouis & Bernard 2007). Only very few occurrences of seismic repeaters have been reported in underground mines, where these phenomena are rather unexpected since the stress state and the seismic wave propagation continuously evolve with the advancing excavation front (Kinscher et al., 2020). A recent study based on a local seismic network installed in the underground mine of Garpenberg, Sweden, has shown that seismic repeaters and multiplets represent the main part of the total released seismic energy (magnitude of seismic events: -2 < M <1, on moment magnitude scale), with some seismic families being active during several months to years. It is suggested that repeaters are linked to aseismic slip on pre-existing talc-filled fractures, induced by the excavation, and loading of asperities. These results imply that part of redistribution of stresses in the mine is due to aseismic slip, which might explain the observed distant and delayed seismicity.

Apr 26, 2022

By E. A. Martell, K. S. Sweder

INTRODUCTION Lung cancer in uranium miners has been attributed to alpha irradiation of basal cells of the bronchial epithelium by radon daughters, primarily by 7.7 MeV alphas from polonium-214 (Altshuler et al., 1964). It also has been was observed that for a given cumulative radon progeny exposure, uranium miners who smoke cigarettes have an incidence of lung cancer about 10 times higher than nonsmoking miners (Lundin et al., 1969). It has been pointed out that the large excess of lung cancer deaths among smoking uranium miners is a multiplicative effect (Doll, 1971), which suggested possible synergistic interactions between airborne radon progeny and cigarette smoking. Experimental studies of the complex pattern of interactions between radon progeny, cigarette smoke particles, and the cigarette smoking process are in progress in our laboratory. Preliminary results, reported elsewhere (Martell, 1981), implicate alpha radiation from indoor radon progeny in the etiology of lung cancer in all cigarette smokers. Cigarette smoking produces high concentrations of smoke particles of low mobility and respirable size--particles between 0.5 and 4.0 µm in aerodynamic diameter (see below). The attached fraction of indoor radon progeny is highly dependent on the air concentration of small particles from cigarette smoking and from other combustion sources (Martell, 1981). The size distribution and other properties of radon progeny associated with cigarette smoke particles enhances their effectiveness in the induction of bronchial cancer in man. In this paper we discuss the properties of radon progeny associated with cigarette smoke, the fractionation of radon progeny and modification of their aerosol properties in burning cigarettes, the role of 218Po in these processes, the production of insoluble 214Pb and 212 Pb enriched particles in burning cigarettes, and the consequent differences in the patterns of polonium isotope alpha irradiation in the bronchial epithelium of smokers. EXPERIMENTAL PROCEDURES Experimental methods used in these studies involve the use of small experimental chambers of known radon and radon progeny concentrations in combination with aerosol collection and sizing techniques and sensitive radioactivity detection methods. The use of low-level [ß-] counting for radon progeny determination, providing a measure of 214 Pb plus 214Bi activity, makes it possible to carry out chamber experiments with small radon emanation sources and relatively low air concentrations of radon and radon progeny concentrations in the range from 100 to 1,000 pCi per liter. Thus, for example, in a typical experiment we use a 10 nanocurie 226Ra solution standard in a 10 liter chamber, providing an equilibrium concentration of 1,000 pCi of radon per liter. In small sealed chambers, radon progeny plate out rapidly on the chamber walls, with steady-state concentrations of airborne progeny less than 2 percent of equilibrium levels. This is experimentally convenient because, upon introduction of high concentrations of cigarette smoke particles or small particles from other sources, there is a systematic ingrowth of attached radon progeny, providing a tagged aerosol source of known age and radon progeny composition. In some chamber experiments a 226Ra solution standard of small volume, acidified to O.1N HNO3, was used as the radon emanation source. When used with a bubbler the holdup of radon in an 8 ml volume of 226Ra solution standard at 0.1N HN03 was only 2% of the total radon in the chamber at equilibrium. For experiments with 212Pb-tagged aerosols, we used a dry Ba(228Th) stearate emanation source prepared by the method of Hursh and Lovaas (1967). 226Ra and 222Rn determinations were made by radon gas counting. The 222Rn in a sealed air or water sample is transferred, using helium gas as a carrier, successively through a dry ice cooled trap at -80°C to remove water, through ascarite to remove C02, and through a small activated charcoal trap at -80°C to collect the 222Rn. Subsequently, by heating the charcoal to 400°C, the 222Rn is transferred next to an LN2-cooled capillary trap, and finally into an alphascintillation counting cell of the type described by Lucas (1957). As already stated, radon progeny activities were determined by low-level [ß-] counting, which provides a measure of 214Pb plus 214Bi. The radon progeny samples, collected on efficient Delbag polystyrene micro-fiber filters or on impactor foils, are placed in close, sandwich geometry between two thin-walled flow counters inside shielding anticoincidence counters and a 15 cm thickness of steel shielding. This configuration provides nearly 4II geometry and a low background of only 0.25 to 0.30 cpm. Aluminum absorber was added to provide a combined thickness of absorber and counter wall exceeding 7.0 mg/cm2 to eliminate the variable contribution of 7.7 MeV alphas from 214Po. 212 Pb determinations also were carried out by low-level [ß-] counting, in this case using a combined absorber and counter wall thickness of 9.0 mg/cm2 to eliminate contribution of 8.8 MeV alphas of 21 Po. In each experiment the [ß- ]activity data were corrected for decay to an appropriate common reference time for assessment of activity distributions.

Jan 1, 1981

By Thomas W. Traylor

Today, in Detroit, Michigan, a 14 ft. 6 in. diameter soft ground tunnel is being mined at penetration rates limited only by the logistics of liner handling and spoil removal. Soil conditions are highly variable and include clays ranging from very plastic to very hard, gravels, sands, silts and boulders. The permeable soils contain high concentrations of methane gas, compressed by groundwater levels some 40 ft. above tunnel invert. Despite these adverse conditions, mining crews frequently complete their 70 ft. production quota in six hours and go home. In one 4000 ft. reach of tunnel, progress averaged 68.9 ft. per mining shift. This paper has been written to explain this extraordinary accomplishment, and to demonstrate that truly continuous rapid excavation in difficult grounds is now limited by factors other than the excavation process itself. BACKGROUND The Detroit metropolitan area has a long and interesting history of soft ground tunneling. From 1949 to 1968 the city of Detroit alone constructed some 75 miles of soft ground tunnel. During this period the development and common usage of rotary or "wheel-type" soft ground tunneling machines was pioneered in the Detroit area. These machines are designed for, and were successful in, the cohesive or clayed soils that predominate the downtown Detroit geology.

Jan 1, 1997

By M. E. Poad

In 1986, a cooperative effort by the Homestake Mining company, the U.S. Bureau of Mines and the University of Utah was initiated to determine shaft stability while recovering high grade ore in a nearby pillar. Premining finite element simulations indicated the shaft would remain in elastic ground. Six years have elapsed and, despite some initial concern during the first lifts, it appears that the bulk of the original reserve will be safely and profitably recovered. An integrated application of rock mechanics tools from laboratory testing through numerical modelling to mine measurements and observations contributed substantially to the operational success of the project.

Jan 1, 1994

By D. R. Rathburn

Jan 1, 1962

By Colin P. Pigott

The paper describes a variety of existing techniques and equipment which when combined together permit faster and cheaper drilling of shafts in soft to medium strength formations. Drilling fluid circulation, methods of hole stabilisation and bit design, including the advantages of flat bottomed and conical bits, shrouds and skirts, tungsten carbide, long tooth and disc cutters are considered. The principles of rock chip transportation and bottom hole cleaning are described together with a new and very efficient fluid circulation system which was invented by the author.

Jan 1, 1985

By Horst Huettenhain

The Rowland Coal Preparation Plant is located on Workman&apos;s Creek in Raleigh County, West Virginia, approximately 20 miles Northwest of Beckley and 10 miles Southeast of Ameagle. It is owned and operated by the Rowland Division of Consolidation Coal Company. This paper describes the plant flowsheet, process considerations that were evaluated in its development, and observations made during and since the plant was constructed. The final flowsheet was developed specifically to wash the coal from the Rowland Mine and contains several equipment combinations and applications heretofore never placed in a single, commercial operation. The major process equipment is presented in a functional description of the flowsheet. The coal reserves are leased from the Rowland Land Company and consist primarily of #2 Gas and Middle Eagle coals and various major splits of the Middle Eagle seam. The Rowland Coal Preparation Plant was designed to process 560 TPH of raw coal consisting of 50 percent #2 Gas coal intimately mixed with 50 percent Middle Eagle coal and containing lumps no larger than a 12-inch cube.

Jan 1, 1970

By Richard Belair, John Read

Ask someone what they can tell you about the Royal Canadian Mint and most likely the first thing that they will mention, is coinage. The Royal Canadian Mint manufactures Canada&apos;s one-cent coins, nickels, dimes and quarters - over 1 billion per year. Most of these coins use copper and nickel as base material, and all of this metal is mined, refined and processed in Canada prior to being shipped to the mint for coin production. In 1985 alone, 1270 metric tons of Canadian nickel and 2160 metric tons of Canadian copper were absorbed in circulating coinage. July 1987 will have marked the introduction of Canada&apos;s new one dollar coin, an important new addition to Canada&apos;s monetary system. The first phase of this program will consume about 2,235 metric tons of Canadian nickel in the initial production run. Annual requirements in subsequent years are estimated at 225 metric tons. The Royal Canadian Mint is also a major producer of circulating coinage for foreign countries. Since the state-of-the-art Winnipeg plant swung into full production in 1976 the Mint has struck more than 5.2 billion coins for some 35 nations around the world. 1985 sales have increased almost 6 fold over 1984. 1987 already shows commitments for a further significant increase in volume in this business. The use of Canadian metals in export to foreign nations as coinage adds still more to the Royal Canadian Mint&apos;s key role as a major market maker for Canada&apos;s mining industry. The success of the Mint in this realm can be directly traced to it&apos;s 75 years as one of the world&apos;s most important refiners of gold. Today, the Royal Canadian Mint is the largest refiner of gold in the Western Hemisphere, and the third largest, by volume, in the world. The R.C.M. hallmark on kilo bars, 100 troy ounce comex bars

Jan 1, 1987

The Río Agrio of northern Patagonia, Argentina, is highly acidic due to inputs of volcanic gases (SO2, HCl, HF) in its headwaters. The watershed includes a hyper-acidic (pH <0.5) volcanic crater lake, a larger glacially carved lake that is also strongly acidic (pH 2.6 to 2.7) and an acidic river that flows for more than 40 km (25 miles) before its pH is completely neutralized. This unique watershed has many geochemical and biological similarities to acid waters caused by mining. This paper describes the Río Agrio watershed and draws a comparison with some famous acid mine waters. Learning more about naturally acidic lakes and river systems could have important applications to the bioleaching of ores or biological treatment of mine waters. Therefore, it should be of interest to the general community of mining and metallurgical engineers.

Jan 1, 2008

By Richard Snyder

Secretariat of the Coal Mining and Mining Executive Committees&apos; of the National Safety Council (NSC) and Manager of the memberships to both Mining Sections; Senior Consulting Safety Engineer, NSC; member of several committees for consensus Standards of the American National Standards Institute (ANSI); a Certified Safety Professional (CSP) of the Board of Certified Safety Professionals of the Americas, Inc. and a chief proctor for CSP testing and certification procedures, et al. It appears that the tunneling trade is merging into its own renaissance for the decade of the 1970s&apos;, and most likely on past the year 2001. Federal interest in underground excavation, and more specifically, rapid excavation expertise has been on the upswing since the latter part of the 1960&apos;s, mainly due to the pressing national needs for more raw materials based on the rise for material goods and the projective gloom of possible power shortages. On the pure tunneling side the national needs encompass, in the mainstream of priorities, rapid transportation and water supply excavation as the two top contenders. For instance, the estimates for tunnel mileage for the period 1968-1975 are:(1) Subways---85 miles Urban Highways--- 123 miles Intercity Highways---210 miles Water Supply Routes---528 miles at a total of 946 miles of tunnels. The estimated cumulative underground excavation demand in dollar amounts for the period 1970-1989 are:(1) Construction Oriented Demand--- $35 billions Mining Oriented Demand---$34 billions (which includes the coal-oriented demand on the order of 26 billions.

Jan 1, 1997