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By V. T. Dow

This report describes construction details and methods used in driving the 5490 tunnel at the Kennecott Copper Corp, property, Bingham, Utah. The tunnel will provide railroad access to the world-famous open-pit copper mine at the projected 5490 level. This publication is one of a series prepared by the Bureau of Mines to depict mining operations and techniques in various mining districts in the United States. Utah Construction and Mining Go. (formerly Utah Construction Co.), contractor on the tunnel project, began work during September 1956 and completed the project in February 1959. The tunnel is 18 feet wide, 24 feet high, and about 18,000 feet long, It will accommodate a railroad locomotive on standard- gage track. With the exception of the last 1,700 feet, the tunnel is supported by steel sets embedded in concrete lining. The 1,700-fact segment of the tunnel is supported by timber sets that will eventually be removed as the pit is deepened.

Jan 1, 1962

This Department handles all ores prior to blast-furnacing, the object of the operations being to mix the lead-bearing material with fiuxes, eliminate sulphur from the mixture, and produce a homogeneous sintered product which is chemically and physically suitable for treatment in the blast furnaces.During the financial year ended the 30th June, 1937, the tonnage of charge treated was 458,960 tons, containing some 183,470 tons of lead and 8,504,000 oz. of silver.The quantities of the principal components of the charge treated were as follow:-

Jan 1, 1937

By James R. Dunn

Samples were taken of industrial mineral waste materials which are potentially capable of being used for filling underground coal mines for subsidence control in the Pittsburgh and the Scranton-Wilkes Barre areas of Pennsylvania. The samples were subjected to potentially relevant standard tests which are commonly used 1n the evaluation of soil materials and mineral "aggregate materials. Measurements of plasticity, liquid limit, and gradations, particularly in the -200 mesh size range, indicated a comparative lack of clay minerals. Cementitious reactions between sources of alkali, such as calcium hydroxide or portland cement stack dust, and of silica, such as clay or fly ash, were found to occur in various mixes of high-bulk materials. Strengths of up to about 400 psi at 84 days were observed. The possibility of emplacement of high-bulk material by both turbid flow (or density currents) below water and by mud flows above water were considered and both appear to be reasonable and possibly simpler than the current mechanisms of emplacement.

Jan 1, 1977

In a gravity separation device, particle shape, size and density all play a role. The combination of these determines where each individual particle reports to in the viscous fluid, where particle crowding (solids to water ratio) also plays a role. To understand the performance of gravity separation devices in the heavy mineral industry, these particle characteristics need to be measured. There are various challenges in analysing particle density and particle size simultaneously for the purpose of quantifying gravity separator performance, not to mention particle shape. These analytical challenges include the high cost of high-density sink-float fractionation, toxicity of high-density sink-float media, inability of sink-float media to fractionate at densities greater than 4.0 g/cm3, and the time-intensive nature of these fractionations. The use of the detailed particle-by-particle output from Qemscan® particle mineral analyses (PMA) as a fast and cost-effective alternative is evaluated. The size and density outputs from the Qemscan® were employed to characterize the performance of a heavy mineral spiral concentrator as an example. Critical analytical requirements are to be addressed before the Qemscan® output data can be utilized. Keywords Gravity separator, performance, heavy minerals, Qemscan® particle mineral analysis

Jan 1, 2011

The Ocean Drilling Program (ODP) is the largest international geoscience project in the world, and the state-of-the-art drill ship, the JOIDES Resolution, is permanently at sea. Each year there are six scientific cruises (legs) which each last approximately two months. These legs are designed by geoscientists from the nineteen countries that subscribe to ODP.Australia and Canada presently share ODP membership under the banner of the AUSCAN Consortium. The benefits of Australia's involvement in ODP include internationalisation of Australian geoscience, advanced graduate training, and unique scientific investigations of the ocean floors in the Australasian region. In addition, visits to Australian ports by the ODP drill ship, the JOIDES Resolution, contribute up to $2 million per visit to the local economy. Amongst the many other aspects of ten years of scientific drilling, OOP has significantly contributed to our understanding of hydrothermal processes on the seafloor. To date, three hydrothermal sites have been drilled to date by the OOP, Snakepit (MAR), Middle Valley (Juan de Fuca Ridge) and TAG (MAR). Two more hydrothermal sites are scheduled for 1996.

Jan 1, 1995

By L. G. Stolarczyk, J. Duncan

"SynopsisLong before the environmental movement, coal miners were suffering from occupational diseases that became apparent in the later years of service, and especially during the retirement years. Chronic exposure to micro-fine dust in the respirable range (‘float’ dust) causes various lung diseases, referred to as coal mine dust lung disease. In the USA alone, 76 000 miners have died of coal mine dust lung disease since early legislation recognized the issue in 1969. Researchers believe that reducing float dust exposure limits alone will not reverse the increasing incidence of coal mine dust lung disease seen in the current generation of miners. Trace and radioactive metals are concentrated in the thin boundary layers of the coal seam (Roberts, 2013), and hence float dust includes silica and toxic trace metals. The production and quality of coal is also significantly impacted by the presence of these contaminants in the coal. In the combustion process, the trace metals are oxidized and become incorporated in the fly ash and flue gas. Since they are extremely water-soluble, they represent a significant danger to health and the environment. Coal preparation plants and power stations need to mitigate these contaminants as far as is practical, but the simple fact is that most contaminants should have been left un-mined.This paper describes an innovative coal-cutting solution to the longstanding technology gap in mining – the ability to measure uncut coal layer thickness to the boundary rock layer. Because of constant changes in geology, seam thickness, and seam undulation, the horizon sensor must be located in the bit-block of the rotating cutter drum of the mining machine. Contaminants in ROM coal must be minimized at the source – that is, at the rock/coal crushing cone directly under the bit-tips of the cutting drum. Bittip distances to the rock boundary layer must be automatically controlled in real time when mining in a complex and undulating coal bed. Horizon sensing (HS) technology enables the mining machine’s cutting picks to stop at a specified distance from undulating horizons of the boundary rock. The thin contaminated coal layer can be left in situ, significantly reducing the toxicity of the float dust. Preventing the metal picks from striking quartz-containing boundary rock also reduces the occurrence of methane ignitions. HS technology equipped with pick force vector sensing can allow optimization of the cutting pick lacing pattern for minimum coal and rock crushing, thereby reducing float dust. This technology may enable the mining industry to convert from automated machine control to autonomous during coal cutting and loading."

Jan 1, 2015

By Jack Mantel

The goal of this 42-month contract was to increase safety in low-seam underground coal mines through development and in-mine evaluation of a temporary roof support system for roof drills and floor-riding operator compartments for a loader and shuttle car. The program was performed in three phases. During Phase I, state-of-the-art canopy technology was investigated, and preliminary design and mock-up evaluations were performed for temporary roof supports for single-and dual-boom bolters and for transverse-mounted floor-riding canopies for a shuttle car and coal loading machine. The shuttle car and loader canopies were approved for further development, and the design, fabrication, testing, and certification were completed in Phase II. In Phase III, the Bureau of Mines furnished an FMC 6L shuttle car fur use in the evaluation of the canopy for 45 shifts. The shuttle car canopy was evaluated at Virginia Crews Coal Company in West Virginia. Efforts to secure an evaluation site for the loader canopy were unsuccessful. The loader canopy was shipped to Bruceton for possible future evaluation.

Jan 1, 1985

By Duane A. Smith

They are gone now. Gone like that long ago generation that gave them birth. The Homestake Mine, nestled in the northern Black Hills, closed in 2001 after 125 years, the longest run of any major American gold mine. The Homestake Mining Co., which guided its destiny for those many years, is gone too. It merged with Barrick Gold. The Hearst family, which guided the early destiny of both, has long since gone beyond its mining heritage and into the national and even international spotlight. The mine and the company passed from the scene with as little fanfare as heralded their birth, amid the Black Hills gold rush of the 1870s. They both grew into American mining legends, as did the town they sired and nurtured, Lead. In a real sense, the mine and the company symbolized one of the last links to a vanished world and a mining era.

Jan 1, 2003

"4.1. IntroductionThis chapter reviews the geochemistry of the platinum-group elements (POE) in sulphur-poor silicate rocks, and the limited data on POE in silicate, oxide, sulphide, arsenide and sulpharsenide minerals. The earliest geochemical studies of POE in silicate rocks, minerals and meteorites were carried out mainly by Goldschmidt, the Noddacks and their co-workers, and are reviewed in Crocket (1969). These researchers established the siderophile character of the POE, emphasized the common association of the group with sulphides in ultramafic-mafic rocks and suggested that very low concentrations of POE are typical of sulphur-poor silicate rocks and minerals. Much of these data were for Pt and Pd only and are more than 50 years old. Because of the poor sensitivity typical of the available analytical methods, few reliable data were obtained on silicate rocks in these early studies. Surveys of POE geochemistry demonstrate that the data base for sulphur-poor silicate rocks is very restricted, although considerable highquality data for Pd and Ir have been accumulated (Wright and Fleischer 1965, Yushko-Zakharova eta/., 1967, Mertie 1969, Crocket 1969, 1979, Keays 1981).Two recent publications, Vol. 71, No. 7 (1976), of Economic Geology (An Issue Devoted to Platinum-Group Elements) and Vol. 17, Part 2 (1979), of The Canadian Mineralogist (Nickel-Sulphide and Platinum-Group-Element Deposits), are of special interest. These volumes are clear testimony to the impressive progress made in the last decade toward describing the mineralogical and geochemical aspects of POE ore deposits, but at the same time demonstrate the constraints in modelling POE ore genesis due to our meager knowledge of the. POE content and distribution among minerals in the source rocks of ultramafic and mafic magmas. It is clear that the phases hosting POE in mantle source rocks are poorly understood. Nevertheless, Naldrett and Duke (1980) have shown that the absolute and relative concentrations of POE in magmatic sulphide ores are related to the degree of partial melting of mantle peridotites, and subsequent processes of batch equilibration and fractional segregation of sulphides."

Jan 1, 1979

By James P. Sloss

WHAT is the likelihood if any-that a real gold mining industry will be developed in the southern Appalachian region? Has the increase in the dollar value of gold from $20.67 to $35 per ounce potency to turn the trick? Suppose it be assumed that the price of gold will, at worst, not recede, and that the cost of digging ore and treating it of which the average level of commodity prices and wages is a fair index-will, at most, not exceed that prevailing in 1926. One may or may not accept these as reasonable assumptions; but one must arbitrarily remove some of the potential variables if one is to get anywhere on a problem like this. As a matter of fact, this article is not going to venture a conclusive answer to the question that has been posed; but it will endeavor to present some of the factors that have a bearing on the problem. The writer spent ten days visiting a dozen properties in Virginia and the Carolinas early in April, 1935, and in doing so got a first-hand slant on mining conditions in the domain of King Cotton.

Jan 1, 1935

By G. L. Oldright

The first Report of Investigations of the present series (No. 4562) was on the fundamental properties of lead compounds, and the manner in which they set limits to the richness of lead products treated in the usual sintering-blast furnace units. These properties of the compounds were emphasized, as' it was desired, also, to learn the limitations of smelting the same compounds in present ore hearth practice; the hearth has a competitor in these "usual" units, even with the rich lead feeds best adapted for the hearths. Operating conditions that were followed in older metallurgical processes, when rich products, were treated, were outlined. The second report of the series (R. I. 4563) was on the development of the ore hearths of the types now used in the Tri-State from the viewpoint of the features, functions, and dimensions of the earlier hearths that had been most changed. Experimental data, for both well and poorly desulfurized charges being considered, were given to show the relative changes in the sizes and compositions of the charges after they were added to the ore (Scotch) hearths. A general picture was given of the charge column and of the conditions prevailing there when the operation was satisfactory. In this third paper, the composition of the gases prevailing in the charge column at various elevations will be correlated with what has been learned of the nature of the charge column in order to trace the steps of operation by which lead sulfide is converted into metallic lead. The metallurgical factors that govern operation and the lines along which improvements may be made will be noted.

Jan 1, 1949

By Louis A. Turnbull

An investigation of coal deposits near Cerrillos Santa Fe County, N. Mex., was undertaken 14 the Bureau of Mines in 1943 as part of a general program to determine sources of metallurgical coal for western steel plants. Almost all of the coal used for metallurgical purposes west of the Continental Divide Is mined from the Lower Sunnyside bed in, Carbon County,, Utah. Coke used in western steel plants that is produced from Lower Sunnyside a coal is weaker, structurally, than coke used elsewhere in this country. For this reason, western coal operators and steel manufacturers are anxious to develop new areas of coking coal of better quality then the coal produced from the Sunnyside bed. The objective of investigations of western coals was to (a) develop additional reserves of coking coal to supplement proved reserves in the Sunnyside bed. and (b) develop; if possible, reserves of coal with coking quantities superior to those of Lower Sunnyside

Jan 1, 1951

By Bruno Gemmi

The objective of the ? 200 million ($280 million) project Parma Railways Station-Urban Transformation was the reconnection of the North and South parts of the town by constructing an 80 m (250 ft) wide sunken artery passing under the four double railway tracks of the station without any impact on train traffic. The site of the project, adjacent to the Parma River, presented water seepage problems at any excavation depth. The use of conventional large diameter bored pile machinery was not allowed by the Railway Authority because equipment dimension and construction phases do not comply with train traffic safety regulations. Foundations for the bypass were thus constructed by minipiles nested into jet-grouted soil using machinery operating within the existing head room and at a safe distance from the tracks. Jet-grouting treatment reached depths of 25 to 28 m (80 to 90 ft) from tracks? grade and embedded minipile-heads were terminated at 2 to 3 m (6.6 to 10 ft) below grade. Load tests on minipiles were pushed to failure. Failure occurred at a 240 t (265 t) load without breakage of the bond between the jet grouted soil and the minipiles. A 0.93 MPa (135 psi) shear resistance ??? between minipile steel casing and the jet grouted soil was measured prior to the failure of the steel casings. Overall measured foundation settlements were well within expected values and were considered insignificant.

Jan 1, 2011

This paper is in two parts. The first part provides background to coal in New Zealand, information on Solid Energy the Company and details of the resources, mines and products of the company. This part of the paper is intended for people who have limited knowledge of the New Zealand coal scene. The second part of the paper focuses on developments underway in New Zealand and discusses planned or possible changes and opportunities. This paper was first presented at the Coaltrans Asia Conference in June 2000.

Jan 1, 2000

By Lifeng Zhang

The transport of fluid, heat ,and particles (bubbles and solid inclusions) in flowing molten steel is investigated in steel refining ladles, the continuous casting tundish, continuous casting mold and strand, and steel ingot casting processes. The two-equation k-?? model is used to simulate the turbulence. Multiphase fluid flow is numerically simulated with a Lagrangian-Eulerian approach, an Eularian-Eulerian approach and the Volume Of Fluid (VOF) method. The simulation can predict inclusion trajectories, inclusion removal fraction, free surface waves and other phenomena, which can be used to optimize these important metallurgical operations.

Jan 1, 2006

By G. R. Robinson

Aggregate resources consist of sand and gravel, and crushed stone. They are large-tonnage, bulk-minable mineral commodities that are used in construction and industrial activities (Tepordei, 1999, 2001).Rates of aggregate production, use and mine permit approval in the mid-Atlantic region differ by population density. These rates are influenced by economic and human factors, such as demand, costs, land availability and community opposition. In some areas, the local availability of aggregate is limited. This is due to the lack of suitable local source materials for aggregate, the loss of potential high-quality aggregate resource production sites by preemptive land development and restrictive zoning (resource sterilization), and the difficulty of developing and permitting production sites for aggregate.

Jan 1, 2004

By Walter R. Storms

"INTRODUCTION The New Mexico potash exploration described herein was begun in February 1944 with the object of determining the amount of potash ore in the United States Potash Reserve in Eddy County by exploring the deposit from the surface with vertical drill holes. The work was completed in October of the same year after 16 holes had been drilled on the Reserve and in the immediate vicinity.The Potash Reserve is in secs. 26; 27, 34, and 35, T. 20 S., R. 29 E., Eddy County, N. Mex., about 14 miles northeast of Carlsbad, as shown on figures 1 and 1A, Drilling was done in secs. 26 and 35 of the Reserve, in section 14 to the north, end sections 2 and 56 to the east. All work was done on Governnent-owned, unleased land.The Reserve may be reached from Carlsbad by traveling to the north-east by automobile for about 14 miles on the paved U. S. highway 62. This highway passes through the southern part of the Reserve. Other parts may be reached by a State highway that passes along the eastern side of the area, then by poor dirt roads to various drilling sites. A branch of the Santa Fe Railroad also passes across the southern part of the Reserve enroute from Carlsbad to the plant and mine of the Potash Co. of America, a few miles northeast of the project and 22 miles from Carlsbad."

Aug 1, 1947

By P M. Hancock

The West Coast contains one of the world's giant placer gold deposits with production since the 1860s totalling some six million ounces (present day value NZ$ 3.6 billion). The deposits have been worked variously by hand, ground sluicing, hydraulicking and/or elevating, blocking out, deep leading and bucketline dredging. Since the sharp gold price rise of 1979 - 1980 gold production has increased steadily (in spite of the closure of the Kaniere dredge) to some 30 000 ounces (933 kg) in 1984. Production is primarily from some 100 medium scale mining, operations treating 50 - 200 000 m3 of auriferous late Pleistocene fluvial gravels year. In spite of their economic value the deposits remain only poorly investigated and many fundamental questions relating to the origin and formation of the deposits remain unanswered. This paper attempts to describe the geology of the deposits and outline a genetic model for their formation, and then discusses some of the economic aspects and current limitations and opportunities of the growing alluvial gold mining industry of the region.

Jan 1, 1985

By Valentín Pamo Caytano

La electrorefinación en un electrolito de CuSO4 - H2SO4 es usado universalmente para producir cobre de alta pureza a partir de los ánodos impuros. Aunque una parte de las impurezas se disuelve durante la electrorrefinación y se concentra en el electrolito, otros elementos son insolubles y se acumulan como lodos anódicos en las celdas de refinación. Las impurezas deben ser removidas del cobre para cumplir las especificaciones del mercado sobre la ductibilidad y conductividad y para recuperar los sub-productos valiosos como el oro y la plata. En ese sentido, el presente trabajo describe los equipos y procesos que permiten la recuperación del oro refinado en la planta de metales preciosos de la Refinaría de cobre de Ilo.

Sep 12, 2011

By Frank E. Woolley, Robert D. Pehlke

Jan 1, 1965