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By George M. Fowler

EVERY year it becomes more difficult to find new mining districts and new ore deposits. Nearly all of the important discoveries so far can be attributed to surface manifestations overlying the ore deposit. In the future greater skill will be necessary to find ore deposits that give little or no indication of their presence. Mining geology is making progress by broadening its attack upon mineralized regions, by including in its investigations studies of the relation of physical-chemical processes to ore precipitation and various phenomena that heretofore have not always been looked upon as major factors in the problems. Such, for example, are petrographic peculiarities that will help determine structure, aspects of strata or formations favorable or unfavorable to structural deformation or mineralization, and renewed studies of chert and dolomite. This broadening attack is not necessarily being directed to the study of large areas, but rather by doing extremely detailed work in three dimensions in relatively small critical areas to find the key to the structure, reasons for the manner of rock deformation, composition and texture of the rock, and other con¬trolling factors in the larger areas.

Jan 1, 1935

By Chas. F. Jackson

This circular is an abstract of a manuscript-completed in August 1932, which cannot be published in its entirety due to lack of printing funds. It was originally planned to publish the manuscript as one of a series of bulletins dealing with the mining and milling of ores of the principal metals. Because of the common association of lead and zinc minerals in many ore deposits, and because a considerable proportion of the zinc produced in this country is obtained as a by-product of lead mining or vice versa, it seemed necessary to treat the mining and milling of lead and zinc ores in the same volume.

Jan 1, 1934

By T. Braun, J. Parker

On June 25, 1999, BHP Billiton (BHPB) announced the suspension of operations at the BHP Copper Inc.(BHP) San Manuel copper mine in Pinal County, Arizona. Subsequent to this announcement, BHPB aggressively pursued a number of alternatives for the underground mine and open pit facilities, including continued curtailed operations, sale to a qualified mining operator and closure of the property. After consideration of these various alternatives over a 2.5-year period, BHPB announced final closure of the mine site on January 15, 2002.This paper describes how the BHPB charter and HSEC policy apply during the closure process.

Jan 1, 2004

By N Clarke, R Dineen, W Jones

The Mt Lyell copper mine in western Tasmania has discharged acid drainage (AD) into the Queen and King Rivers and Macquarie Harbour for over a century. Presently, dissolved copper loads of about 1000 tonnes per annum and dissolved aluminium loads of >2000 tonnes per annum are contained in the AD, which is derived from underground workings (~60 per cent) and historic waste rock dumps (~40 per cent). Flows vary from about 100 L/s during dry periods, to >400 L/s during the wet winter. The site is presently operated by Copper Mines of Tasmania (CMT) who are not responsible for the acid drainage generated from the mine site. Although western Tasmania is famous for its mining history, tourism and aquaculture have emerged as the new industries on the West Coast, with a major tourism railway (the Abt) recently opened along the banks of the Queen and King Rivers. The emergence of these industries in a æclean greenÆ Tasmania has resulted in a strong community and government push to remediate the acid drainage. Remediation investigations and efforts at Mt Lyell were initiated by the Department of Primary Industries, Water and Environment (DPIWE), previously known as DELM, in 1995, and have included the quantification of environmental impacts arising from the AD, and the investigation and costing of potential remediation options. A primary focus of the work has been to identify cost-neutral options which recover metals from the AD in a saleable form to help defray on going treatment costs. This paper summarises these activities in generally a chronological order, highlighting findings of the program that are potentially applicable to other acid drainage sites.

Jan 1, 2003

By John J. Mulligan

Coalbeds were discovered in outcroppings of the Beacon group of sediments on the north end of the Willett Range ( altitude 77 ° 11 ' S , longitude 160 ° 20 ' E ) , Victoria Land , Antarctica , in December 1960 during an investigation undertaken as part of the U.S. Antarctic Research Program under the auspices of the National Science Foundation . Three separate exposures of coal or coaly material were found . Two of the exposures contain , respectively , eight and four beds of hard , compact , finely banded attrital coal ranging in thickness from 8 feet downward to a few inches , and reported to range in rank from mediumvolatile bituminous to semianthracite . The coals are associated with carbonaceous shales containing an abundant assemblage of fossil plants resembling those associated with the Permian coals of Australia and other Gondwana areas . The third exposure , apparently somewhat higher in the stratigraphic sequence , contains only coaly plant fragments scattered through a thin conglomerate and overlying sandstones . A sandstone bed that overlies these coal - bearing sandstones contains abundant logs and fragments of silicified wood . Preservation of features is poor , but one segment of a silicified stem suggests comparison with Rhexoxylon , a gymnospermous tree that usually is considered indicative of Triassic age . The Beacon sediments in this area have been invaded , broken , and uplifted by a massive series of diabase sills and dikes greater in volume than the intruded sediments . The heat emitted by these intrusives must have advanced the metamorphic development of the coals . However , there is no evidence of alteration to graphite , and coal found in direct contact with a diabase sill contains no vesicles or other usual evidences of natural coking . Either the pressure of overlying rocks inhibited the development of coke , or the coals had been metamorphosed beyond the coke forming stage before the igneous intrusion .

Jan 1, 1963

By W. S. Steinberg

In 1963, the full-scale engineering study for the development of an iron, steel, and vanadium plant was initiated. This was the birth of Evraz Highveld and its process flow as it is known today. Highveld started out as a steelworks that produced steel and vanadium-bearing slag from a titaniferous magnetite iron ore mined from its own mine site near Steelpoort. The process utilized co-current rotary kilns for prereduction, and submerged-arc furnaces for the production of pig iron with approximately 1.15% vanadium. Because of various technical challenges that the submerged-arc furnaces experienced over the years, a decision was taken in 2004 to convert the furnaces to open slag bath (OSB) operation, in order to enable the maximum production of iron and vanadium while improving the control over operational parameters. The conversion proved to be highly successful and, since 2005, three furnaces have been converted to OSB operation. The fourth furnace will be converted in the first half of 2011. The conversion to OSB furnaces not only yields higher vanadium recovery to the metal at the iron plant, but also improves the overall throughput of the steel plant. This is the result of the higher carbon content of the liquid iron from the OSB furnaces, eliminating the need for anthracite addition to the shaking ladle process. This reduces the blowing time by approximately 60%. The conversion of the furnaces to OSB configuration is seen as an enabling technology change and a prerequisite to the implementation of other plant improvements that are envisaged. The long-term vision of EHSV is to convert five furnaces to OSB mode, and permanently decommission the two remaining submerged-arc furnaces. This will allow EHSV to maintain current steel and vanadium production but at a significantly improved overall efficiency.

Jan 1, 2011

By Francis Chachula, Niel Erasmus

"In 2002, Titanium Corporation Inc. focused its attention on the development of a process for the recovery of valuable heavy minerals, including zircon and titanium bearing minerals from oil sands froth treatment tailings. The development of a process flowsheet to recover the titanium and zircon minerals from the Athabasca oil sand tailings has evolved through many laboratory, bench and pilot scale iterations.Initial development work focused on so-called ‘beach sand’ material, which is tailings material deposited over a period of time close to the tailings pipe discharge. The derived process flowsheet primarily consisted of gravity concentration stages, which is typical of all mineral sands operations. Titanium Corporation’s business plan calls for the utilization of tailings directly from the tailings pipeline – the process developed around the beach material is therefore risky as it differs from the live tailings in a number of aspects, with the effects on the process unknown. Titanium Corporation successfully obtained an intermediate product through a ‘bulk sampling plant’ coupled directly to an Oil Sands operator’s froth treatment tailings pipeline, during the summer of 2005. Subsequent further processing of this material resulted in poor separation or concentration of the heavy minerals due to a number of reasons. A more effective process flowsheet had to be developed.The newly derived process is basically a marriage between mineral sands technology and oil sands technology that can economically concentrate and recover the heavy minerals and entails the incorporation of a flotation process that takes advantage of the entrained bitumen in the feed to separate the heavy mineral fraction from the quartz gangue This paper will describe the newly derived process as well as the successful results of a subsequent on-site concentrator pilot campaign completed during the 3rd Quarter of 2006."

Jan 1, 2008

By Michelle L. Ramos

INTRODUCTION The Ballard Siphon was built in 1935 and consists of two 91.4 cm (36-inch) diameter wood-stave pipes. These pipes convey sewer flowsunder the Ship Canal from northwest Seattle and the Ballard Regulator to the North Interceptor and the West Point Treatment plant. The siphons were constructed using open cut construction, are now buried in the sediment on the floor of the canal, and have severely limited ability to be dewatered, inspected, or cleaned. The existing siphon is 394.7 m (1,295 feet) long from the junction structure on the southern shoreline to the regulator structure on the north. The location of the Ballard Siphon is shown in Figures 1 and 2. The area around the Ballard Siphon has become more populated and developed since the siphon was built. Additionally, the Ballard Siphon is subject to high flows that are greater than the capacity of the pipelines. This has resulted in predict-able Combined Sewer Overflows(CSO?s) whenever a large, long duration rain event occurs. The aged pipeline of uncertain viability has become a critical piece of the sewer system infrastructure. Because of the age of the pipelines and their importance, a sonar survey was completed on both barrels of the Ballard Siphon in December of 2005. The sonar images appeared to indicate crown intrusion of the wood-stave pipes, which suggested that the pipes were in imminent danger of collapse. As a result, an Emergency Declaration was executed by King County and the Ballard Siphon Replacement Project was initiated. Staheli Trenchless Consultants was retained to perform feasibility studies to deter-mine the viability of using microtunneling and horizontal directional drilling (HDD) for replacement of the Ballard Siphon. For the evaluations, the preferred site location was determined to be at or near the site of the existing Ballard Siphon in order to minimize the ancillary sewer work which would accompany moving to a new site. To meet flow demands and hydraulic requirements, the replacement siphon needed a mini-mum equivalent diameter of 182.9 cm (72 inches). This could be accomplished with a number of different siphon diameters and configurations including, but not limited to, three 106.7 cm (42-inch) diameter pipelines, two 152.4 cm (60-inch) pipelines, or two 91.44 cm (36-inch) pipelines and a 121.9 cm (48-inch) pipeline.

By A. Engelbrecht, B. North, B. Oboirien

"There is large electricity generation potential in discard coal, both in stockpiles and current arisings. Power stations with a combined capacity of up to 18 GW electrical (GWe) could be fuelled by discard coal. Modern circulating fluidized bed combustion (CFBC) boilers, with capital costs comparable to equivalent pulverized fuel (PF) boilers, are capable of utilizing discard coal at a high efficiency while reducing sulphur dioxide (SO2) emissions though the use of limestone sorbent for ‘in-situ’ capture.A detailed economic assessment of the feasibility of electricity generation from discard coal, comprising material and energy balances and the construction of a discounted cash flow (DCF) table, shows that it is also potentially attractive from an economic perspective. A base case analysis shows positive net present values (NPVs) and an internal rate of return (IRR) of 21.4%. Sensitivity analyses on critical parameters show that the economic viability is heavily dependent on parameters such as coal cost and the value of electricity. The project becomes unattractive above a coal price of approximately R300 per ton and at an electricity value below approximately 59c per kilowatt-hour (kWh).Site- and project-specific information such as the delivered cost of coal, location and efficacy of sorbents, and effective value of the electricity produced can be used as input to the economic analysis to evaluate siting options and sorbent source options for such a power station."

Jan 1, 2015

By R. Barthel, O. Nitzsche, J. Pateiro Fernández, T. Cramer

The Hong Gai coal field in northeast Vietnam has been the main coal mining area of Vietnam for more than 150 years. Anthracite coal is produced from several open pit and underground mines situated close to the UNESCO world natural heritage site Ha Long Bay. The mining-induced environmental impacts such as dust emissions, acid mine drainage, and visual impairments due to waste dumps resulted in severe conflicts of interests regarding future land use and the protection of the world natural heritage site Ha Long Bay. Within the RAME project (Research Association Mining and Environment in Vietnam), Brenk Systemplanung is contributing to an improved environmental and sustainable planning in Vietnam's mining industry and the reduction of environmental impacts on Ha Long Bay by developing suitable and sustainable technology and planning measures (e.g. for dump construction/rehabilitation, predictive modelling, and/or monitoring) for Vietnam's leading coal producer.

Jan 1, 2011

By Keith A. Heasley, Timotlly M. Barton

Historically, the surface subsidence over underground coal mines has been predicted using empirical profile or influence functions which have little or no connection to the actual mechanics of the subsidence- Without a mechanistic basis, establishing the exact site-specific parameters to use in these empirical methods has been problematic. A practical subsidence predictive method based on mechanics has the appealing capability of allowing the determination of site-specific parameters from fundamental properties of the overburden with minimal field calibration work. This paper presents a case study where a mechanics-based, boundary-element program is used to calculate the surface subsidence associated with several panels of a Northern Appalachian longwall coal mine. The program used in this case study is called LAMODEL, and it incorporates a frictionless, laminated overburden into a general purpose displacement-discontinuity code primarily designed for calculating the stresses and displacements in coal mines or other thin seam or vein type deposits. In this paper. the program is used to calculate both the underground convergence and the resulting surface subsidence at three longwalls. The subsidence results from the model are compared with field measurements and analyzed The results from the case study in this paper demonstrate that the laminated model with calibrated properties can easily provide fairly accurate subsidence predictions and is fairly flexible for fitting measured subsidence. However, additional subsidence predictive case studies are recommended in order to ultimately evaluate the potential of the laminated overburden model for practical subsidence prediction

By C. H. Mathewson

MY treatment of the subject of "Metals of the Future" is imaginative rather than statistical or scientific, because reliable information concerning useful concentrations in the form of ore deposits of by far the majority of the elements does not exist and the chemical, physical, and mechanical properties of the unfamiliar metals are recorded only in fragmentary and uncertain form or not at all.

Jan 1, 1944

By M. H. Kline

The Cranberry magnetite deposits occur in pre-Cambrian granite-gneiss, in a belt extending from 3 miles southeast of Cranberry, N. C., to about 6 miles southwest of Magnetic City, Tenn. The belt forms a curve) elongated to the north, approximately 26 miles in length. The Bureau of Mines investigation has been confined to the eastern part of the belt, comprising the area from Fork Mountain, Avery County, N.C., to the Hcupscup Knob prospects in Carter County, Tenn. The deposits were worked at least us early as 1820. The Cranberry Iron & Coal Co. and its successors operated the Cranberry mine intermittently for about 50 years until 1930, when operations were abandoned.

Jan 1, 1948

By Chung Yu, Wang

CHINA can he roughly divided into three metallogenetic province: North China, the Yangtze Valley, and South China. In North China the old Pre-Cambrian schists and gneisses are represented by the abundance of quartz mines in which sporadic occurrences of copper, lead, zinc, gold, and silver are sometimes found in subordinate quantities. Along the Yangtze Valley and in Central China, extending eastward as far as Shantung, are found here and there intrusions of dioritic rocks, in which occur the famous contact deposits of iron ore, besides which minor quantities of copper. lead, and zinc are also found. In South China the igneous intrunsions are of granitoid type in which, or in the vicinity of which, occur in certain regions immense deposits of antimony, tungsten, tin, and mercury. Broadly speaking. most of the famous coal mines are now situated in regions north of the Yangtze River, in which occur also the sedimentary deposits of iron in contradistinction to the contact deposits of iron along the Yangtze Valley.

Jan 1, 1943

By H. Boghosian

This paper presents the design and construction of a deep basement in a steeply sloping site in glacial till in Glasgow city centre. Existing foundations, adjacent structures and services, in tandem with asymmetric loading, presented particular challenges in the planning, execution and design of the project. The construction methods and temporary works, analysis by the Finite Element method and monitoring carried out are all described.

Jan 1, 2006

"It is projected that the reactivity of acid generating tailings and waste rock can be minimized by reducing the access of oxygen by placing these materials under water in natural or manmade lakes. A project under the MEND and B.C. AMO Task Forces has been in progress for four years to evaluate active and historic tailing sites in B.C. and Manitoba. The sophisticated geochemistry studies conducted on the interstitial pore water has illustrated encouraging results which are discussed. The additional studies which are needed to complete the scientific database for the study sites, for achieving regulatory and public approval and for the engineering of application of this method of control are outlined.IntroductionWorld wide research effort is in progress to find the solution to the acid mine drainage problem. A great deal is known about acid mine drainage but much work is required to find economic and effective approaches to the problem. Two coordinated programs have been initiated recently in Canada: the National Mine Environment Neutral Drainage (MEND) program and the British Columbia Acid Drainage Task Force.Disposal of tailings materials under a water barrier such as a natural lake, is thought to be one solution to prevent acid generation by preventing oxygen and bacterial action on the sulphide surfaces. The deposition of reactive tailings materials under water in natural lakes has been used historically at various mines in Canada. However, there has never been a thorough review of the long and short term impacts of historic sites which may provide crucial information to understand the physical, chemical and biological processes which are taking place.This paper provides a general overview of a series of studies which examine the general biophysical characteristics and the sediment geochemistry of four lakes where subaqueous disposal has been or is currently being used for acid generating tailings. The subaqueous disposal studies have been conducted from 1989 through 1991 and were initiated and supported by both research task forces. The objectives of this paper are to summarize the history and the background information of the studies conducted, the general results obtained from each lake, an overview of the major collective results and the additional work which is required to achieve the final objective of developing criteria for applying this technology in the industry."

Jan 1, 1992

By J. G. Kirby

According to the Bureau of Mines annual survey, as of January 1, 1954 there were 337 refineries with a total daily crude-oil throughput capacity of 8,006,897 barrels. The total daily capacity increased 368,236 barrels during the year while the total number of refineries declined 6. The capacity of the average refinery to process crude oil therefore increased during 1953 from 22,270 barrels to 23,759. With the exception of the Texas Inland, all refining districts reported gains in the installed capacity for the year, the largest being the Louisiana Gulf Coast with an increase of 20 percent. A total of 397,500 barrels of additional crude oil capacity was reported as under construction January 1, 1954. Accounting for 129,500 barrels of this total are facilities for 3 new refineries in North Dakota, 2 in Washington and I each in Ohio and Utah. Equipment being installed to replace existing units, totaled 180,750 barrels daily.

Jan 1, 1954

By T. Y. Yunsel

Estimation techniques such as polygonal, triangular prism, trapezoid, isopach maps, and inverse distance methods are often used in ore or industrial minerals deposit evaluation. These techniques do not express the variability of the deposit and do not allow a determination of the reliability of the estimates. However, geostatistical methods can express a measure of the error associated with the estimates, by finding weighting coefficients for a given mining block, and can also help with data configuration that minimizes the error. This work addresses an application study on the quality and reserve characteristics of the cement raw materials of the Adana Cement Factory in Adana, Turkey, based on the spatial distribution and variability of the chemical components (Si02, CaO, A1203, Fe203). The study has been carried out using a geostatistical procedure that is useful for site assessment, characterization, and monitoring situations where data are collected spatially. Directional and omnidirectional experimental variograms of the cement raw material variables showed that neither strong geometric nor severe zonal anisotropy exists in the data. The most evident spatial dependence structure expressing the continuity for omnidirectional experimental variograms were characterized by exponential and spherical variogram models. These models have been used in cross¬-validation analysis, which proved that these models, their parameters, and kriging parameters are applicable for the study area. Quality contour maps of the deposits at given levels underground were estimated using a kriging interpolation technique. Anomalies such as bullseyes and drift were not observed in the maps that were generated. Kriged maps showed the spatial distribution of quality continuity and variability of the deposits. Grade-tonnage curves and total tonnage estimates in the particular grade were determined using ordinary kriging in order to improve the mining operation and planning. Consequently, local uncertainty and the probability of extreme values occurring are tools of prime importance for the mine planning, the optimum mix of raw materials coming from different quarry stopes.

Jan 1, 2012

By Brenda M. Dixon

A matrix analysis of the differences between the camps and communities associated with the Britannia Mine is used to develop an analytical tool. The tool is intended to assist the mining industry as it embraces the many facets of sustainable development. A case study is used to support the identification of key factors that may predict the sustainability of a new mine town. Sustainable communities, like Britannia Beach, are discussed in the context of three pillars of sustainability: value of mining products to society; creating wealth; and, environmental integrity. A sustainable mine town may be viewed as a socio-economic asset as well as an asset to the mining industry.

May 1, 2006

By Laurens de Jonge, Wiebe Boomsma, Rodney Norman, Stanislav Verichev

"Earth provides natural resources, such as fossil fuels and minerals that are vital for human life. As the global demand grows, especially for strategic minerals, commodity prices rapidly rise. Thus there is an identifiable risk of increasing supply shortage for minerals. Hence a major element in a long-term economic strategy must be, to ensure security of supply for these strategic minerals. In this rapidly changing global economic landscape, deep sea mining has gone from a distant possibility to a likely reality within just a decade.Although deep sea minerals extraction was investigated in the 1970’s, it was abandoned because of changing commodity economics, advances in on-land exploration techniques, growing concern on environmental impact, and political and legal aspects with regard to ownership issues. The developmental data from those days, if still available, are not adequate to allow engineering and building of an integral system for extraction of deep sea minerals without additional R&D work. Thus, deep sea mining is yet to attain a Technology Readiness Level (TRL) sufficient to successfully undertake deep sea mining operations, from resource discovery to resource assessment and to resource exploitation [Blue Mining, 2014]."

Sep 1, 2014