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By Mary E. Learmont

Grinding with steel media adversely affects the flotation response of galena. Electrochemical measurements, flotation tests, and AES, XPS, and STEM examinations were employed to identify interactions between galena and mild steel. Iron oxide, hydroxide, or sulfate species that formed on the galena surface upon contact with mild steel decreased its floatability, with the time of contact and aeration condition affecting the severity of the flotation depression.. Parallel tests performed with an active metal, magnesium, indicated that floatability was also affected by the presence of a surface coating involving lead species.

Jan 1, 1984

By T. Takamori

This paper reviews the present status of coal preparation in Japan concentrating on the process in coal cleaning and waste water treatment. This paper also discusses recent topics on maintenance, automatic control, raw coal management, etc.

Jan 1, 1982

By Kousik Sinha

The advantage of using a clean coal as a feedstock in a direct liquefaction plant is improved performance of the plant by several factors e.g., increased throughput of coal; reduced wear and tear of valves, pipes, and pumps; increased liquid yields, etc. This paper examines the technical feasibility for cleaning Illinois #6 coal as a feedstock to a direct coal liquefaction plant via selective agglomeration using a coal-derived heavy distillate, Wilsonville V-1074 as agglomerant. Effects of addition of Kerosene or coal-derived Naphtha as conditioner, coal particle size, slurry pH, oil to coal ratio, and operating temperature on ash reduction and clean coal weight recovery have been studied. Results show that about 70% of the ash can be removed from this coal and the clean coal weight recovery over 85% can be achieved by using this technique with suitable selection of coal particle size, slurry pH, mixing intensity and oil to coal ratio.

Jan 1, 1991

By L. J. O’Connor

Mining activities in the small historic mining camp of La Colorada in the state of Sonora, Mexico can be traced back to the mid eighteenth century when gold was discovered and exploited by Jesuit missionaries. Following one hundred and twenty six years of activity, the mines were shut down due to the Mexican revolution. Very little activity took place until 1989 when a company, Minera Las Cuevas, spent US $350,000.00 in mapping and sampling and diamond and reverse circulation drilling over a period of three years. During 1991 HRC Development Corporation entered into a joint venture agreement with Minerales de Sotula, S.A. de C.V. that allowed an earn in of 70% interest. Exploraciones Eldorado, S.A. de C.V. and it's parent company, Eldorado Corporation Ltd. were subsequently incorporated by HRC to hold the La Colorada project. Property evaluation ensued and a thirty thousand tonne Run of Mine test heap was leached from August of 1992 until May of 1993. Full scale commercial production commenced in late November, 1993 and the first gold/silver doré bar was poured early in January of 1994. Pre-production costs were a total of approximately four million dollars U.S. During the fall of 1994 a buyout of the venture partners' interest gave Eldorado one hundred percent ownership of the property. The first two years of mining have utilized a local contract mining fleet and have placed nearly two million tonnes of ore on a run of mine heap. Low cost ripping and dozing mining methods have been employed in conjunction with drip irrigation leaching. An initial pilot plant carbon adsorption circuit was supplemented with a Merrill Crowe recovery circuit in June of 1994 and was completely replaced with the construction of a second Merrill Crowe circuit in July of 1995. Approximately fifty thousand troy ounces of gold and over one hundred thirty thousand ounces of silver will have been poured by year end 1995. Ongoing, on site exploration continues to increase mineable reserves in the known deposits. A feasibility study is ongoing concurrent with the operations and will provide the basis for future elevated production levels. Exploraciones Eldorado continues to explore outward from the current operations and several anomalous outlying zones may play part to the long term economic growth of the company in Mexico.

Jan 1, 1996

By R. P. Schneider

The Chino mine, concentrator, and smelter are located in Grant County in Southwestern New Mexico. Chino Mines Company is a partnership two-thirds owned and operated by Kennecott Santa Fe Corp., and one-third owned by MC Minerals Corp. (Mitsubishi) of Japan. The Chino Ore Body The Chino ore body is a widely varied deposit of rock types and contains intrusive stocks and sediments. The stocks contain chalcocite in a matrix of quartz, mica, and feldspar. Much of the feldspar is altered to clay. Some of these stocks are enriched with native copper. The sediments contain chalcopyrite associated with gangue minerals including magnetite, pyrite, garnet chlorite, and epidote. The contact of the stock and sediment is heavily altered to chlorite and clay. The stock ores contain economic quantities of molybdenite. The operating work index of Chino ore varies from 5 to 20 kwh/ton and averages 8.5 kwh/ton. The ore head to the concentrator averaged 0.81% copper and 0.010% molybdenum. Fifteen percent of the total copper head exists as nonsulfide mineralization.

Jan 1, 1985

The exploitation of mineral deposits for economical recovery of the contained minerals has many aspects differing from other industrial or manufacturing operations. However, generally accepted principles of good organization and management applicable to industrial plants are similarly effective for mineral processing plants. A more detailed coverage of organizational structures and management techniques than is possible in this section can be obtained from many good books devoted wholly to these subjects. A few of the more readily available examples are included in the general references at the beginning of this section. The field of mineral processing encompass a wide variety of minerals, processes, flowsheets, equipment, and end products. Mineral deposits, mines, and related beneficiation plants are found in all parts of the globe, often in remote locations with no nearby support for supplies and maintenance. Available labor is frequently unskilled, sometimes primitive, and often untrained without machine and hand tools or heavy equipment experience. Such situations call for well- planned and conducted training programs covering the full range of mining-type job skills. Climates can range from arctic to tropical and from arid to extremes of rain or snow, and the mine and plant sites can be almost anywhere. However, it is often possible and sometimes necessary for

Jan 1, 1985

By Armando M. Lago

This paper reviews the postwar changes that have occurred in the expenditure and financial behavior of mineral corporations, and in particular the relative importance of factors that affect the industry's supply and demand for funds. This quantitative statistical investigation of factors affecting sources and uses of funds of mineral corporations is achieved through the formulation of a simultaneous equation model of sources and uses of funds. After a description of the study sample in Section I, the postwar cyclical and secular financial behavior of mineral corporations is analyzed in detail in Section II. Section III formulates an econometric model of mineral corporate financial behavior which is then estimated and reviewed in Section IV. Section V discusses policy issues regarding depletion allowances, investment tax credits, and industrial organization of the mineral sector. Finally, the optimum financial structure of mining firms is discussed in Section VI, which analyzes the effect of corporate financial structure on the mining corporations' average Cost of capital.

Jan 1, 1969

By Ramon B. Santos

The Atlas Concentrator, reputedly the largest in the Far East today, is located on the island of Cebu in the Republic of the Philippines. It started operation on a 4000 TPD capacity in 1955. An expansion program, coupled with significant improvements both in the Crushing Plant and the Mil, made the Atlas Concentrator what it is today, treating about 14,000 tons of ore per day at a comparatively low cost of about $0.50 per ton treated. The Atlas Copper Mine is at present mainly an open pit operation, with ore supplied from two pits (Lutopan and Biga) north of the Concen¬trator. Development of an Underground Mine, situated on the main ore body at Lutopan, which will be a block caving operation, has been underway since 1963, and this underground mining operation is expected to b e in full production by the latter part of 1966.

Jan 1, 1966

By Xiaobo Zhang, Panshi Xie, Xiaobo Wu, Ding Lang, Jiandong Yu, Yongping Wu, Kun Feng

In a fully mechanized top coal caving mining process, the mechanical properties of the top coal deteriorate constantly, and the stability of the support is determined by the boundary position of the top coal entering the limit equilibrium state. Top coal flaking occurs more easily along the advancing direction owing to an increase in the distance of the boundary from the wall. Moreover, the strength of the coal seam is an important factor that determines the boundary position. The equation of the top coal limit equilibrium zone boundary, used in fully mechanized top coal caving mining, was determined based on the limit equilibrium theory, continuum damage mechanics, and the Hoek–Brown rock empirical strength criterion. Using the RFPA3D and UDEC numerical analysis methods, the effect of top coal strength on the mechanical behavior during the mining process was determined; and the space–time relationship between the top coal deformation failure, damage evolution, and boundary of the limit equilibrium zone was established. The results revealed that when the coal mass entered the limit equilibrium zone, accelerated crack development, accelerated damage, and axial unloading occurred. Moreover, an increase in the coal seam strength caused the boundary of the top coal limit equilibrium zone to be closer to the wall. By comparing the numerical results with the theoretical results, the overall trend was found to be consistent, allowing the verification of the rationality and reliability of the determination equation of the boundary position of the limit equilibrium zone.

Sep 21, 2021

By W. D. Elston, A. E. McLaughlin, G. B. Hampton, W. L. Barham, J. F. Murphy, W. H. Cundiff, J. W. Mulloy, R. G. Breuer, J. W. Shaffer

Introduction Alumina (aluminum oxide) is the material from which all the world's aluminum is produced. In the Western World, all the alumina is made from bauxite by the Bayer process. In the nearly 150 years since aluminum was first isolated by Oersted, the metal has grown from a laboratory curiosity to a position of major importance in the world's commerce. In terms of annual production rates aluminum is first among nonferrous metals. Oersted's discovery-reduction of aluminum chloride with potas¬sium amalgam-was improved on by Ste. Claire Deville, whose so¬dium amalgam reduction of aluminum chloride led to the commercial production of aluminum in France in 1855. Ste. Claire Deville's method prevailed until 1886 when Charles Martin Hall and Paul T. Heroult each invented a process for the production of aluminum by the electrolysis of alumina dissolved in molten cryolite. The inven¬tion by Karl Josef Bayer in 1888 of an economical process for making very pure aluminum oxide (alumina) from bauxite established the necessary link between known ores and the Hall-Heroult reduction process. Bayer's work completed the scientific base-the ore bauxite refined to alumina by the Bayer process (U.S. Patent No. 515,895), the alumina reduced to aluminum in the Hall-Heroult cell (U.S. Patent No. 400,766--upon which today's aluminum industry is founded. Small-scale production of aluminum in the U.S. began in 1888 utilizing the Hall cell. By 1903, bauxite properties and a Bayer process refining step had been incorporated into the production activities. On this base the aluminum industry in the U.S. has grown at an annual compounded rate of 15%. Since 1946 the annual growth rate has been 10%.1 The rapid growth of the industry is the result of many factors among which are the existence of widespread bauxite ore deposits; a sound and economic production technology; and the properties of the metal-lightness, strength, ductility, good electrical and heat con¬ductivity, and pleasing appearance, which lead to ever greater de¬mands for aluminum in an industrializing society. At the inception of the industry, the only market that could be found for aluminum was in the production of cooking utensils. How¬ ever, the rapidly accelerating industrial and technological development of the Western World soon created new needs for aluminum, and today aluminum is marketed in a broad range of industrial, commer¬cial, and consumer applications. The principal uses for aluminum are:' building and construction, 22%; transportation, 18%; electrical, 13%; packaging, 11%; consumer durables, 10%; machinery and equipment, 7%; other, 19%. The 1974 production of primary alumi¬num in the world was 14.5 million short tons, which at an approximate ingot price of 40¢ per lb puts a value of $11.6 billion on the industry product prior to fabrication. While aluminum is widely distributed in the earth's crust and is a major constituent of many rocks and soils, to date no method of extraction of aluminum from such nonbauxite material has been brought to commercial practice in the Western World. In the USSR alumina is produced by the complex processing of nepheline syenite, but elsewhere all commercial production of alumina is from bauxite. A brief discussion of recent developments and other processes for alumina is included in the subsection "Other Processes for Alumina," page 19-15. In early 1973, a major U.S. aluminum producer announced the successful development of processes for the production of aluminum from aluminum chloride. This achievement promises to exert a major influence on the future of the aluminum industry. In the initial com¬mercial application of this new technology, Bayer alumina will be chlorinated, and the aluminum chloride then reduced by electrolysis. Important claims for the new processes are lower energy requirements (one-third less than obtainable in Hall cells) and reduced labor costs. Capital costs are said to be no greater than for conventional plants. While the announced intention is to produce the aluminum chlo¬ride from Bayer process alumina, the new chloride reduction process will eliminate the other raw materials, carbon and fluorides, required by the conventional Hall cells. The electrodes in the chloride cell will not be consumed on the reduction process and the electrolyte will have, as the name indicates, a chloride rather than a fluoride base. 2. Bauxite Definition and Origin. Bauxite is a naturally occurring raw material composed principally of a mixture of one or more of the hy¬drated aluminum oxide minerals gibbsite (Al2O2 3H2O), boehmite (Al2O3 H2O), and diaspore (Al2O, - H2O), and impurities of silica, iron oxide, titania, and other various elements in trace amounts. It is an end or near-end product of chemical weathering. Depending on the amount of iron impurities, the color of bauxite varies from dark red and brown to pink to white. Some bauxite is finely divided, free digging earthy material, while other forms are dense and rocky, requiring explosives in mining. Many gradational forms exist. It is one of the most variable of mineral raw materials in chemical composition and physical appearance. It is generally believed that bauxite deposits resulted from intense chemical weathering of aluminum-bearing rocks or formations under tropical or subtropical conditions with alternating wet and dry sea¬sons. Topographic conditions were favorable for drainage and the in-situ accumulation of aluminum, iron, and titanium oxides. There was low to moderate topographic relief with a minimum of erosion during long quiet periods in earth history.2 The occurrence of bauxite is widespread and it has been found on all continents except Antarctica. Production was reported from 27 countries in 1974, at which time total world production was over 79 million metric tons. Of this production 76% was from seven coun¬tries-Australia, Jamaica, Surinam, Guinea, USSR, Guyana, and Greece-which ranked in that order of production. In Table 1 are shown typical compositions of bauxite from some

Jan 1, 1985

By Michel Dagbert

With the growing demand for energy, explora¬tion for uranium deposits has dramatically increased in the past few years. Since the early ages of uranium exploration, natural gamma ray logs has proved fast and convenient in locating and evaluating mineralized bodies. However, natural gamma ray logging is an indirect measure of the uranium content and in some circonstances, the radiometric signal can be 'altered in a very significant way. To check the presence of any distortion, statistical comparision of radiometric counts and chemical assay values for the same samples is generally performed. Of course in such studies, one inevitably mixes samples where the radiometric signal is really proportional to the uranium content and samples where this signal is influenced by many other sources or distorted before being recorded. Nevertheless, the average tendency leads to correction factors which are then applied to every radiometric reading in the deposit or portion of the deposit where the statistical comparison is made. To account for the "average" character of these correction factors, a parameter of uncertainty like a standard deviation of possible errors is associated to each corrected value. This parameter can be latter used in an ore reserve estimation when the weights assigned to samples should depend on the precision of their grade. The purpose of this paper is to present a new regression technique which can be used without any restrictive hypothesis like a normal or lognormal distribution. Different standard ways which can be used to statistically compare radiometric and chemical assay values for the same sample and to derive a correction factor for the latter will first be reviewed, after a general discussion of disequilibrium problems. The discussion and the examples will be restricted to the case of natural gamma ray logging in drill holes but the methods presented in this paper can also be applied to data from the radiometric probing of a working face or a truck load in an operating mine.

Jan 1, 1979

By R. C. Schmidt

The Mont Klahoyo magnetite deposit is located about 600 km northwest of Abidjan, Ivory Coast. During an exploration period ending in 1977 an international joint venture group investigated the deposit and proved reserves of 670 million tons grading 36% iron. The deposit, occurring at the northeast end of the Baoubly-Kiriao chain of Precambrian iron formations, is associated with amphibolites, pyroxenites and gneisses of the Liberian Shield. At Mont Klahoyo occur two separate iron formations of which the lower member is the ore body. This lower member consists of a highly metamorphosed - banded quartz-magnetite iron formation in which iron silicate bands alternate with beds of quartz-magnetite. mphibolite-pyroxenites and sillimanite-cordierite-garnet gneisses form hanging and footwall rocks. The iron formation has been folded into an elongated overturned "Z" shaped major drag fold with axes trending and plunging approximately northeast. Beds are vertical or dip steeply to the southeast. The ore zone has an average thickness of 130 m and outcrops intermittently over a distance of approximately 5.5 km. Based upon detailed studies of drill cores and the results of ore dressing test work, eight stratigraphic units, identified as K-1 to K-8, are recognizable in the iron formation. Four interbedded units are low grade silicate zones (silicate facies) with the remaining quartz-magnetite units (oxide facies) repre¬senting the important ore zones of the Mont Klahoyo deposit. The ore-bearing "K" units are subdivided further, based upon their specific lithologies, iron content and concentration characteristics, into eleven ore types. The identification of these ore types is considered particularly important to mine planning and flowsheet design. A cap of oxidized materials overlies the primary quartz-magnetite iron formation but no enrichment has occurred. It is proposed that the Mont Kalhoyo iron formations were deposited, possibly chemically, in a volcanic environment as a siliceous iron formation with volcanism providing the primary source of iron and silica. Metamorphism converted the siliceous iron formation to a relatively coarse-grained quartz-magnetite-silicate iron formation.

Jan 1, 1979

By J. R. Brett

Utah Development Company (UDC) operates five large opencut coal mines in the Bowen Basin of Central Queensland, Australia. In total, over 20 million tonnes of coking coal are exported annually from the five mines. Typically, the coal seams dip at 5 percent, are 2 to 10 metres thick, and sub-crop some 20 to 40 metres below surface. In the main, the operations are single seam, but multiseam (2, 3 or 4 seams) operations do exist and will form an increasing proportion of the mining activities as depths increase. Draglines are used as the major stripping equipment, highwall depths currently ranging from 20 to 65 metres. Whilst project feasibilities were based on stripping to a 60 metre highwall, it is now proposed to continue opencut mining to depths exceeding 100 metres. This will entail large quantities of prestripping (ahead of the draglines) and overcoming problems associated with steepening seam dips, including haulage of coal from the pits.

Jan 1, 1982

By Melvin W. Jackson

The study of the excavation of large spherical cavities in salt formations first became of interest in 1958 when it was recognized that a large cavity could be of value in the study of the detection or concealment of underground nuclear explosions. Previously unpublished studies are reported in this paper and other studies reviewed relating to the excavation of large cavities in salt by mining ad by solution. Special emphasis is placed on the utilization of the Tatum salt dome (about 22 miles southwest of Hattiesburg, Mississippi) for the proposed site of a large excavated cavity. The U. S. Atomic Energy Commission has recently been studying such a cavity as Project Payette, but no details have yet been published. If Project Payette is determined feasible and work funded, it would eventually involve the firing of a nuclear explosive at the center of a large cavity.

Jan 1, 1969

By Chuang Sun, Feng Luo, Guo‑dong Li, Xue‑qing Li, Tuan He

The mining-induced failure of the coal seam floor is essential for water inrush. The mining disturbance to the floor, especially in the thick coal seam, is severe, and the water inrush risk is also higher than that in regular thick coal seam excavation. The superposition of many stresses, including in situ stress, mining-induced stress, and confined water pressure, must be considered in the prediction of the floor failure depth. This study adopted the elasticity analysis, FLAC3D numerical simulation, and on-site acoustic wave test comprehensively. The thick coal seam working face of the Zhong-Yu coal mine affected by confined water was selected as the engineering background to study the characteristics of the floor failure. Based on elastic foundation theory and the superposition principle, the mechanical model and the failure depth criterion of the floor were established, respectively. The distribution and evolution of mining-induced stress and the plastic zone in surrounding rock during the mining process are obtained by FLAC3D. In addition, the changes in the P-wave wave velocity in the floor before and after mining were compared and studied by the acoustic wave test method. The range of floor damage depth is determined on the basis of the above research.

Jun 8, 2022

By A. Juganda, Jr. Bogin, S. Saki, R. Gilmore, J. Brune, J. Grubb, S. Lolon

"In longwall mines, atmospheric or barometric pressure fluctuations can disturb the pressure balance between the gob and the ventilated working area of the mine, resulting in a phenomenon known as “gob breathing”. Gob breathing triggers a gas flow across the gob and the working areas and may result in a condition where a methane accumulation in the gob flows into the face area forming an explosive mixtures. This paper discusses results of Computational Fluid Dynamics (CFD) modeling carried out to analyze this phenomenon and its impact on the explosive mixture development under a bleeder-ventilated longwall gob panel scheme. Modeling results indicate that the gas inflow and outflow across the gob and the formation of Explosive Gas Zones (EGZs) are directly affected by the barometric pressure changes. Methane gas and EGZs in the gob expand out toward the face and bleeder entries during the falling barometric pressure. Where methane zones interface with mine air, EGZ fringes may form along the face and in the bleeder entries. When the atmospheric pressure increases, an ingression of oxygen into the gob is observed that can also increase EGZs in volume. The findings from this study help assess the methane ignition and explosion risks associated with fluctuating atmospheric pressures. INTRODUCTION Methane explosions continue to be a daunting risk for underground coal miners, although the number of related fatalities and injuries in the U.S. coal mining industry has steadily decreased since the establishment of the U.S. Bureau of Mines in 1910. Still, the consequences of a methane explosion are often disastrous with multiple fatalities and property damage often leading to permanent shutdown of the mine. Methane is formed during the coalification process and is released from the coal seam to the mine atmosphere when the coalbed is disturbed by mining or natural causes such as earthquakes. If not properly diluted by appropriate mine ventilation, this methane may accumulate in the active mine workings and gob areas. Researchers at the Colorado School of Mines have developed numerical models showing how and where explosive methane may accumulate in gob areas. Historical mine explosions appear to show a connection between mine explosions and fluctuating barometric pressure as a result of stormy weather. McIntosh (1957), Boyer (1964), and Kissell et al. (1973) studied the influence of barometric drops on major coal mine disasters in the United States prior to 1970. Their statistical analyses found that a majority of these disasters occurred in the fall and winter months when the barometric pressures were influenced by unstable weather conditions and noted increased methane content in the mine workings during times of falling pressure. Studies conducted by Fauconnier (1992) and Hemp (1994) found similar connections between methane explosions and barometric pressure fluctuations in a majority of gas explosions in South African mines. Ten out of twelve major mine explosions with five or more fatalities in the U.S. after 1970 were found to have occurred during the months of November through April when barometric pressure swings were more abrupt and intense (Lolon et al., 2015)."

Jan 1, 2016

By Emanuele Catelli, Paolo Vicentini, Manuel Petitat, Paolo Lanfranchi

"More than 800 million tons of material will be excavated during large underground projects such as tunnels, undergrounds and power plants by 2030 in Europe only. The raw material excavated is often classified as waste, which involves environmental impact and transport issues: landfill areas, CO2 emissions and noise. But how can such massive amounts of material be transported, processed and deposited? Using the example of the AlpTransit Ceneri Base Tunnel (15.4 km), we show that suitable excavated materials can be used sustainably as a primary resource for tunnel concrete. This requires careful planning of the installations and storage areas by the client, timely building of the processing plants and other handling facilities outside the tunnel and a continuous evaluation of the raw material quality. 1. INTRODUCTION Spoil management is a central element of large construction projects. The systematic reuse of suitable excavated material not only saves natural resources, reduces transport distances and landfill volume, but can also decrease overall construction costs. Ideally, all of the concrete needed for tunnel lining can be produced with this on-site material. Such a natural resource management concept was applied for the construction of the new Gotthard Base Tunnel (L = 57 km). Spoil management concepts are, how-ever, difficult to implement and call for innovative techniques, sophisticated logistics and organization. In the context of large projects, environmentally friendly transport, processing and storage of millions of tons of excavated loose material represent another logistics challenge (Simmen & Lieb, 2010). This paper shows key factors that led to the successful completion of spoil management at the Ceneri Base Tunnel, which constitutes a part of the AlpTransit Gotthard Project (Figure 1)."

Jan 1, 2016

By Dan Nilsson

Open pit mining is the strong sector of the American mining industry. In the middle of the 60's. 17-18% of the ore in metal mines was mined with underground methods. From the middle of the 60's to 1980 the production in open pit metallic mines increased from about 400 to close to 600 million short tons while at the same time the underground mine production decreased a little, from about 90 to about 80 million tons. Less than 15% of the ore prodction now come from underground mines. Large amounts of waste rock were also handled in the open pits. In the middle of the 60's about 600 milion tons were handled, in 1980 1,200 million tons were moved. This means that the average stripping ratio increased from about 1.5 to over 2.0 tons of waste rock per ton of ore, figure 1.

Jan 1, 1983

By I. Iwasaki

Precious metals are commonly believed to be recovered along with sulfide minerals in flotation, but a few neutron activation analyses showed that the recoveries of gold and silver were unexpectedly low. Recoveries of platinum group metals remained unresolved due to interferences in the analyses. Electron micro-probe, scanning electron microscope and scanning auger microprobe analyses have identified nickel arsenide minerals in the ore and confirmed a close association of platinum group metals with the arsenide minerals as minute inclusions. These results indicated a need for re-evaluation of flotation procedures which have so far ignored special problems related to arsenide minerals. The electrochemical and flotation behaviors of nickel arsenide and their implications to the flotation recovery of arsenide minerals from copper-nickel bearing Duluth gabbro are presented.

Jan 1, 1985

By Richard A. Levins

The imposition of non-market regulations, such as the proposed SO2 standards for coal combustion, will typically lead to less efficient (thus more costly) production in a free enterprise system. For the coal industry these increased costs will occur in several ways, among which are mining less accessible low sulfur reserves and transporting low sulfur coal to distant markets. There are, of course, social benefits of reducing the S02 emissions from the use of high sulfur coal. The social benefits include decreased health risks, reduced damages to property, and certain unmeasurable benefits associated with the aesthetic appeal of clean air. Proponents of Federal S02 standards argue that the benefits gained from reduced emissions will exceed the costs borne by the coal industry and society in general in meeting the regulations. The purpose of this paper is to investigate the degree to which costs of meeting future energy demands from coal will change under different sulfur standards. No attempt is made to estimate the benefits of imposing regulations. Specifically, the impact of SO2 standards on the private costs of meeting regional coal demands, the competitive positions of the nation's major coal producing regions, the degree to which strip mining as opposed to underground mining will be feasible, the amount of coal being processed, and the amount of coal transported over major rail routes will be analyzed.

Jan 1, 1976