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By J. J. K. Daemen

Mining Engineering education is in trouble, if not in crisis. The most visible signs are the decrease in the number of programs that offer the degree, and the continued difficulties in attracting students to the discipline. Unless these trends are reversed, the future of the profession is uncertain, at best. Remedies have been proposed, and some are drastic. They range from consolidating mining engineering education into one or two national schools, to cooperative regional programs, to distance education programs, and to proposals to limit mining engineering to a graduate degree or specialization only. These alternatives deserve serious attention and merit discussion. I hope that one alternative that will remain on the table is the classical and traditional “School of Mines”. A reasonable number of such schools are needed to provide the educational diversity and the critical mass to maintain accreditation and professional registration for their graduates. Most importantly, such an approach is most likely to assure the continued existence of mining engineering as a profession. It also provides the best educational framework to teach mining engineers. However, such Schools are vulnerable, highly susceptible to university budget pressures, and probably can survive only with strong external support.

Jan 1, 2004

By M. B. McClenaghan

"This paper summarizes diamond exploration techniques used in glaciated terrain, focussing on indicator mineral and geochemical methods applied to glacial sediments. Understanding the ice flow history, depositional history, and stratigraphy of glacial sediments is essential to successful sampling, interpretation and follow-up of indicator mineral and geochemical anomalies related to kimberlites. Kimberlite indicator minerals survive glacial transport over long distances and the relative abundance of each mineral in till is a function of the primary mineralogy of individual kimberlites. Indicator mineral distributions observed at a regional scale define the net effect of glacial dispersal, often along different ice flow directions. Local-scale distributions define individual dispersal trains. The medium sand (0.25 mm to 0.5 mm) fraction of heavy mineral concentrates, * GSC Contribution No. 2002028 prepared from glacial sediment samples, is best suited for indicator mineral surveys. The application of till geochemistry to diamond exploration is increasing because it is significantly cheaper than indicator mineral analysis and it can be performed quickly. The <0.063 mm (silt+clay) and 0.5 mm to 2.0 mm (coarse sand) fractions provide the best geochemical contrast between background and kimberlite-rich till. Kimberlite pathfinder elements that provide good contrast include Ni, Cr, Ba, Co, Sr, Rb, Nb, Mg, Ta, Ca, Fe, K, Ti and LREE, the relative importance of which will depend on kimberlite composition and that of the surrounding bedrock.IntroductionIn Canada, glacial erosion is the principal means by which kimberlite and its associated minerals have been dispersed, from a few tens of metres to tens of kilometres down-ice. Post-glacial weathering has had little impact on kimberlite debris in the glacial sediments, thus boulder tracing, indicator mineral methods and trace element geochemistry of the fine fraction of till (“drift prospecting” methods) can be used to detect kimberlite dispersal within areas covered by glacial sediment. This paper provides a summary of drift prospecting methods for kimberlite exploration in glaciated terrain, and includes examples of reconnaissance- , regional- and local-scale kimberlite indicator mineral and till geochemical distribution patterns.Weathered kimberlite is more susceptible to glacial erosion than the surrounding bedrock, thus many kimberlites in glaciated terrain are found in low or swampy ground, under small lakes, or covered by thin (< 1 m) to thick (>50 m) glacial sediments. Glacial erosion has removed varying amounts of the pre-glacially weathered kimberlite and, in some cases, the hard competent kimberlite below. For example, glacial erosion of the Peddie, McLean and Seed kimberlites near Lake Timiskaming, Ontario, removed pre-glacially weathered kimberlite, leaving a polished striated subcropping surface (McClenaghan et al., 1999a). In contrast, glacial erosion of the B30 kimberlite, near Kirkland Lake, Ontario (Fig.1), was much less vigorous and left a >10 m cap of soft and highly weathered dark green clay-rich kimberlite (McClenaghan et al., 1996). The thickness of remaining pre-glacially weathered kimberlite will influence the geophysical signature of the kimberlite."

Jan 1, 2002

By Barend Botha, Trevor Davids

The presence of an extensive soft siltstone layer in the middle of the inter-burden sequence of rocks at Syferfontein Colliery in the Republic of South Africa prompted tests to determine the effect of different mid-column decks of inert material in the siltstone layer. The objective was to achieve significant cost savings in explosives use whilst not degrading dragline productivity. An important factor that had to be considered was that the initiation systems available in South Africa are not accurate enough to ensure simultaneous initiation of explosives decks in a blasthole. A number of inert materials were tested including ash, drill cuttings, river sand and crushed stone. It was found that the ash, drill cuttings and river sand did not effectively attenuate the shock wave and that the risks of sympathetic detonation or partial disruption of one or the other explosives deck in a blasthole was high. This became much worse when the inert material was saturated with water. Crushed rock was the most effective in attenuating the shock wave, but this material was very expensive to use because it had to be imported onto the mine.

Jan 1, 2000

By Deno Pappas, Chrisropher Mark, John Rusnak, Linda McWilliams

Mine planning for a new reserve is based on information obtained from exploratory coreholes. A critical component of an exploration program is the geotechnical evaluation. Poor assumptions about roof conditions greatly add to the risks of mining. Rock mechanics testing is central to a geotechnical exploration program. Typically, 3 to 5 uniaxial compressive strength (UCS) tests are made to characterize a particular roof unit at a given corehole. The average (mean) of these tests is taken as “The UCS” for that location. Isopach contour maps are then used to show spatial trends in roof strength. Two issues are raised by this traditional approach. The first is due to the large variability in UCS values that is typical even within a single unit from a single hole. The average UCS might be higher at Corehole A than it is at Corehole B, but the difference may not be statistically significant. The second issue is whether widely spaced coreholes can identify valid spatial trends in rock strength. The answer depends upon whether rock strength changes over distances that are longer or shorter than the corehole spacing. This is a classical geostatistical problem. While geostatics have been used to investigate many coal quality parameters, they have seldom been used to evaluate rock strength. This paper describes an extensive investigation of these issues conducted by the National Institute for Occupational Safety and Health (NIOSH) in collaboration with Peabody Energy. The study employed the Peabody Rock Mechanics Data Base which contains more than 10,000 individual test results. Data from four important roof units were subjected to statistical analysis: • Brereton Limestone above the Herrin 6 seam (Illinois) • Turner Mine Shale above the No. 9 Seam (Kentucky) • Sandstone above the Eagle Coal (West Virginia) • Shale above the Eagle Coal (West Virginia) The study did not find significant spatial trends in rock strength in any of the cases. Perhaps there are none, or perhaps the exploration coreholes were just too far apart to see them. These results have valuable implications for the design of geotechical exploration programs.

By S. Klein, D. Crouthamel, D. W. Farmer, S. H. Phillips

Groundwater inflows during construction pose one of the greatest risks to the successful completion of tunnel projects. Inflows can result in safety concerns, difficulty in mining and ground support, impact sensitive environmental habitats, create surface settlement and increase costs. Adequately planned pre-excavation grouting programs benefit both the Owner and Contractor in reducing risks and controlling project costs and potential schedule delays. This paper outlines strategic guidelines for assessment of site conditions for pre-excavation grouting hard rock tunnels. It also describes the design of pre-excavation grouting programs with respect to project requirements.

Jan 1, 2005

Geotechnical conditions in the Lochiel Deposit are somewhat unusual, and thus geotechnical and hydrological investigations have assumed a high priority. The cost of mining the deposit has been shown to be very sensitive to geotechnical design parameters, and it is now seen to be of paramount importance to establish a high level of confidence in the design parameters used for mining cost estimation. Geotechnical investigations in the Lochiel Deposit reached a crossroads in 1985, when there appeared to be several quite different and equally attractive routes to follow to establish a satisfactory level of confidence in geotechnical mine design parameters. Three main options were identified, referred to as the No Further Work Route, the Drill and Trench Route, and the Trial Pit Route. The No Further Work Route was ruled out as being technically unsound and as satisfying none of the Electricity Trust of South Australia&apos;s (ETSA&apos;s) or the State Government&apos;s requirements. The planning process for further geotechnical investigation involved: clearly identifying the current status of work and significant geotechnical and geological factors planning and costing the alternative schemes for improving knowledge assessing the increase in knowledge to be gained from the alternative schemes . choosing the preferred scheme This process resulted in ETSA&apos;s

Jan 1, 1986

By G. S. Littlejohn

Following study of historical South African practice and a review of recent experience gained during the design, construction and testing of the high pressure plugs at the South Deep Water Barrier Project, this paper makes recommendations to improve practice. Initially, site investigation requirements are described with reference to geological, hydrogeological and seismic considerations, including site preparation and pre-grouting of the surrounding rock mass, if permeable. Structural and hydraulic aspects of plug design address topics such as residual permeability, aggressive mine water, plug materials, mortar strength and bleed. In situ thermocouples and piezometers are recommended to optimize the timing of plug tightening and monitor plug performance during service. Plug construction covers aggregate preparation, mortar quality control, plug tightening grouts, injection pressures, records and the overriding need for a method statement specification to control all aspects of plug construction. On completion of the plug, tests to establish surrounding rock stress regime, plug strength, and residual permeability are described to enable a comparison with original design assumptions. Monitoring and maintenance procedures are proposed to ensure satisfactory long-term performance of the plugs.

Jan 1, 2006

By J. Rivoirard

Historically, linear and lognormal krigings were first created to estimate the in situ mineral resources of blocks. Nonlinear geostatistics and indicator kriging were subsequently developed to evaluate also the portion recovered when applying a cut-off on selective mining units (SMUs) within blocks. In practice these methods are generally based either on the Gaussian model with a transformation generalizing the lognormal case or on the indicators above cut-offs. Very often the indicator approach is simplified by kriging separately each indicator, and when starting from a continuous variable, a practical advantage of the discretization into classes lies in the easy treatment of a zero effect and of the high values. However, a number of so-called isofactorial models have also been developed for a discrete or continuous variable, where the full cokriging of indicators (i.e. disjunctive kriging) simplifies to the separate kriging of factors. Moreover, these models are equipped with a change of support, allowing a consistent estimation of recoverable resources on SMUs. Min-Max Autocorrelation Factors (MAF) analysis of the indicators offers a new approach for indicator modelling. In particular the first factor, the one with the highest spatial continuity, can help in choosing the type of model. For example a monotonic experimental first factor can be used directly as the basis of a discrete diffusion model, unless a continuous diffusion model such as the Gaussian model can be used on the original variable. This approach is illustrated on a uranium deposit mined selectively: estimates of recoverable resources by discrete disjunctive kriging and uniform conditioning in a Gaussian model are compared locally to short-term estimates based on two areas densely drilled.

Jan 1, 2014

By J. Glazewski

The mining industry in South Africa has developed its own environmental guidelines in the form of an Aide-Mémoire1,which is an extension of the previous rehabilitation provisions to include all aspects of the environment and all phases of a mining operation. This development, at the time, recognized an international trend towards the formalization of environmental management in mining practice, which resulted from the realization of the large environmental liabilities that mines could face, particularly on closure. Over the past decade the international environmental focus in the mining industry has moved from operational management, to the reduction of liability on mine closure. Mine closure guidelines are being developed internationally by nations (for example, SRK, 19982) and by large mining groups (for example, Rio Tinto, 19983). In South Africa the Department of Minerals and Energy (DME) is presently reviewing the Aide-Mémoire to bring it in line with international and local developments and a separate mine closure plan is being considered.

Jan 1, 2000

By F F. Pitard

The optimization of metallurgical processes requires knowledge of the heterogeneity carried by constituents of interest. The common scenario, almost an industry standard, is to rely on the engineering firm who in turn relies on favorite manufacturers of sampling equipment to provide the appropriate sampling systems in the plant to perform accurate metallurgical accounting. This sequence is flawed from the beginning to the end because everything should be based on a careful understanding of the Theory of Sampling (TOS) by the company project team and their expert who invariably would suggest various approaches and different sampling systems.The necessary progressive and iterative approach should be that the company’s project team (mining or other industries) would do its home work to have a good understanding of the geometallurgy, mineralogy and texture of the ore in each geological unit so consultants and engineers would have the best information to start with. Then a reputable sampling expert would recommend which sampling systems are needed, so the company would require engineering firms to follow pre-established, non-negotiable requirements, and finally select the sampling equipment existing on the market today that is most likely to lead to accurate and precise enough metallurgical accounting.It is the author’s experience that when this necessary progressive and iterative approach is bypassed, sampling systems installed in the plant are likely to transgress the most elementary rules of sampling correctness. Invariably the argument is that the company cannot afford correct sampling systems for metallurgical accounting as suggested in the Theory of Sampling. There is nothing that is farther from the truth when later problems will develop and inevitable reconciliation difficulties with miners and geologists become daily routine with impossible answers; as a last resource the sampling expert may be called to perform a post-mortem analysis.The progressive and iterative approach suggested in this paper should be a due diligence requirement for any bank providing a loan for an important new mining project; anything less is most likely to generate unpleasant financial losses; historical, well-known examples are referred to.CITATION:Pitard, F F, 2015. A progressive, iterative approach leading to reliable metallurgical accounting sampling systems, in Proceedings MetPlant 2015, pp 78–91 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

By S. K. Gilman

Zircon (ZrSiO4) sand production of about 1.1 Mt/a(1.2 million stpy) predominates the global supply of zirconium minerals. Baddeleyite (ZrO2) contributes less than 1 percent of supply. Zircon is almost exclusively produced as a co-product from the mining of titanium minerals, mainly from mineralized beach sands. In 2004, there were a number of new projects under consideration that were more dependent on zircon revenue than for titanium minerals. This reflected sustained higher zircon prices and forecast ongoing supply shortages in the absence of major new discoveries.

Jan 1, 2005

By Charles Ronkos, Jeffrey Edwards, Brian Brodsky

The Marlin gold-silver deposit is in western Guatemala, 15 kilometers south of a major transform fault that separates the North American and Caribbean plates. A district-scale, northwest-trending graben controlled deposition of a greater than 1200 meter thick upper Tertiary quartz latite to rhyolite volcaniclastic sequence. These volcanics were subsequently intruded and unconformably overlain by a small intermediate, latite to andesite, volcanic complex. Classic low-sulfidation, quartz-calcite-adularia veins and stockwork formed a 2.2 million ounce gold deposit, in association with late-stage andesite dike swarms, along a west-northwest striking normal fault on the eastern flank of the volcanic complex.

Jan 1, 2005

By Willem C. A. van Niekerk, David A. Baldwin, Nardus Potgieter, Willie A. Gericke

Authorities that regulate environmental issues pertaining to industrial wastes in South Africa regard landfill disposal as the only effective environmental management option for slag and other inorganic by-products from the ferro-alloy industry. Metallurgical slags are widely utilised in civil engineering and construction applications in other countries in the world and in line with the overall philosophy of conserving mineral and other natural resources, these materials should be assessed for the possibility of resource recovery, recycling, reclamation, direct re-use or alternative uses. This presentation describes a risk-based approach for the assessment of by-products from the ferro-alloy industry for alternative use. Once a by-product from an industrial process has been identified for alternative use, its intended use would be defined, but it will not be possible to control its actual use or misuse in society, nor will it be possible to control its fate during the application life cycle. In the interest of protection of human health and the environment, potential risks associated with the handling and uses of a material throughout its life cycle therefore have to be quantified. The assessment has to include both human health and ecological risks and must cover the entire life cycle of a product, from its production up to its end-of-life disposal. The presentation introduces the concept of tiered risk assessment and demonstrates how this applies in the overall assessment of by-products from metallurgical industry sector for safe use in society.

Jan 1, 2007

LIST OF THE MEETINGS OF THE INSTITUTE AND THEIR LOCALITIES FROM ITS ORGANIZATION Transactions Number Place Date Vol Page 1 Wilkes-Barre, Pa May, ?71 1 3 2 Bethlehem, Pa August, ?71 1 10 3 Troy, N Y November, ?71 1 13 4 Philadelphia, Pa February, ?72 1 17 5 New York, N Y May, ?72 1 20 6 Pittsburgh, Pa October, ?72 1 25 7 Boston, Mass February, ?73 1 28 8 Philadelphia, Pa May, ?73 2 3 9 Easton, Pa October, ?73 2 7 10 New York, N Y February, ?74 211 11 St Louis, Mo May, ?74 3 3 12 Hazleton, Pa October, ?74 3 8 13 New Haven, Conn February, ?75 3 15 14 Dover, N J May, ?75 4 3 15 Cleveland, 0 October, ?75 4 9 16 Washington, D C February, ?76 4 18 17 Philadelphia, Pat June, ?76, 5 3 18 Philadelphia, Pa October, ?76 5 9 19 New York, N Y February, ?77 5 27 20 Wilkes-Barre, Pa May, ?77 6 3 21 Amenia, N Y October, ?77 6 10 22 Philadelphia, Pa. May, ?78 6 18 23 Chattanooga, Tenn May ?78 7 3 24 Lake George, N.Y. Oct. ?78 7 25 Baltimore, Md. Feb. ?79 7 26 Pittsburgh Pa, May ?79 8 27 Montreal, Canada Sept, ?79 8 28 New York, N.Y. Feb, ?80 9 29 Lake Superior, Mich Aug, ?80 9 30 Philadelphia, Pa. Feb, 81 9 31 Staunton, Va May, 81 10 32 Harrisburg, Pa Feb, 81 10

Jan 1, 1923

By Hugo Villanueva

En la actualidad, el supervisor de mina busca optimizar las operaciones de minado para mejorar la productividad del yacimiento minero. Sin embargo, la información recibida sobre minería sin rieles es escaza, así como la experiencia en este sistema. Por ello, el supervisor se limita a esta forma incipiente del sistema. En este sentido, el objeto del texto es otorgar a los supervisores una herramienta que les permita programar o corregir alguna anomalía del sistema de operación a través de una breve descripción del sistema de explotación, standars de operación, definición del standard, cálculo de las asignaciones, standard de las fases principales y el standard de excavación.

Nov 20, 1978

LIST OF THE MEETINGS OF THE INSTITUTE AND THEIR LOCALITIES FROM ITS ORGANIZATION Transactions Number Place Date Vol Page 1 Wilkes-Barre, Pa May, ?71 1 3 2 Bethlehem, Pa August, ?71 1 10 3 Troy, N Y November, ?71 1 13 4 Philadelphia, Pa February, ?72 1 17 5 New York, N Y May, ?72 1 20 6 Pittsburg, Pa October, ?72 1 25 7 Boston, Mass February, ?73 1 28 8 Philadelphia, Pa May, ?73 2 3 9 Easton, Pa October, ?73 2 7 10 New York, N Y February, ?74 211 11 St Louis, Mo May, ?74 3 3 12 Hazleton, Pa October, ?74 3 8 13 New Haven, Conn February, ?75 3 15 14 Dover, N J May, ?75 4 3 15 Cleveland, 0 October, ?75 4 9 16 Washington, D C February, ?76 4 18 17 Philadelphia, Pat June, ?76, 5 3 18 Philadelphia, Pa October, ?76 5 9 19 New York, N Y February, ?77 5 27 20 Wilkes-Barre, Pa May, ?77 6 3 21 Amenia, N Y October, ?77 6 10 22 Philadelphia, Pa. May, ?78 6 18 23 Chattanooga, Tenn May ?78 7 3 24 Lake George, N.Y. Oct. ?78 7 25 Baltimore, Md. Feb. ?79 7 26 Pittsburgh Pa, May ?79 8 27 Montreal, Canada Sept, ?79 8 28 New York, N.Y. Feb, ?80 9 29 Lake Superior, Mich Aug, ?80 9 30 Philadelphia, Pa. Feb, 81 9 31 Staunton, Va May, 81 10 32 Harrisburg, Pa Feb, 81 10

Jan 1, 1938

LIST OF THE MEETINGS OF THE INSTITUTE AND THEIR LOCALITIES FROM ITS ORGANIZATION Transactions Number Place Date Vol Page 1 Wilkes-Barre, Pa May, ?71 1 3 2 Bethlehem, Pa August, ?71 1 10 3 Troy, N Y November, ?71 1 13 4 Philadelphia, Pa February, ?72 1 17 5 New York, N Y May, ?72 1 20 6 Pittsburg, Pa October, ?72 1 25 7 Boston, Mass February, ?73 1 28 8 Philadelphia, Pa May, ?73 2 3 9 Easton, Pa October, ?73 2 7 10 New York, N Y February, ?74 211 11 St Louis, Mo May, ?74 3 3 12 Hazleton, Pa October, ?74 3 8 13 New Haven, Conn February, ?75 3 15 14 Dover, N J May, ?75 4 3 15 Cleveland, 0 October, ?75 4 9 16 Washington, D C February, ?76 4 18 17 Philadelphia, Pat June, ?76, 5 3 18 Philadelphia, Pa October, ?76 5 9 19 New York, N Y February, ?77 5 27 20 Wilkes-Barre, Pa May, ?77 6 3 21 Amenia, N Y October, ?77 6 10 22 Philadelphia, Pa. May, ?78 6 18 23 Chattanooga, Tenn May ?78 7 3 24 Lake George, N.Y. Oct. ?78 7 25 Baltimore, Md. Feb. ?79 7 26 Pittsburgh Pa, May ?79 8 27 Montreal, Canada Sept, ?79 8 28 New York, N.Y. Feb, ?80 9 29 Lake Superior, Mich Aug, ?80 9 30 Philadelphia, Pa. Feb, 81 9 31 Staunton, Va May, 81 10 32 Harrisburg, Pa Feb, 81 10

Jan 1, 1952

LIST OF THE MEETINGS OF THE INSTITUTE AND THEIR LOCALITIES FROM ITS ORGANIZATION Transactions Number Place Date Vol Page 1 Wilkes-Barre, Pa May, ?71 1 3 2 Bethlehem, Pa August, ?71 1 10 3 Troy, N Y November, ?71 1 13 4 Philadelphia, Pa February, ?72 1 17 5 New York, N Y May, ?72 1 20 6 Pittsburg, Pa October, ?72 1 25 7 Boston, Mass February, ?73 1 28 8 Philadelphia, Pa May, ?73 2 3 9 Easton, Pa October, ?73 2 7 10 New York, N Y February, ?74 211 11 St Louis, Mo May, ?74 3 3 12 Hazleton, Pa October, ?74 3 8 13 New Haven, Conn February, ?75 3 15 14 Dover, N J May, ?75 4 3 15 Cleveland, 0 October, ?75 4 9 16 Washington, D C February, ?76 4 18 17 Philadelphia, Pat June, ?76, 5 3 18 Philadelphia, Pa October, ?76 5 9 19 New York, N Y February, ?77 5 27 20 Wilkes-Barre, Pa May, ?77 6 3 21 Amenia, N Y October, ?77 6 10 22 Philadelphia, Pa. May, ?78 6 18 23 Chattanooga, Tenn May ?78 7 3 24 Lake George, N.Y. Oct. ?78 7 25 Baltimore, Md. Feb. ?79 7 26 Pittsburgh Pa, May ?79 8 27 Montreal, Canada Sept, ?79 8 28 New York, N.Y. Feb, ?80 9 29 Lake Superior, Mich Aug, ?80 9 30 Philadelphia, Pa. Feb, 81 9 31 Staunton, Va May, 81 10 32 Harrisburg, Pa Feb, 81 10

Jan 1, 1937

By Bruce Hebblewhite

This paper recognises the 25th year of the Morgantown International Ground Control in Mining Conference, by offering a twenty five year review of ground control in the Australian mining industry ? primarily in underground coal. The paper provides an overview of the developments in ground control design methodologies, practices and products. It not only summarises what has been done, but attempts to highlight at least some of the major issues, significant developments, controversies and areas of contention, plus some of the continuing gaps in our understanding or capabilities as we go forward into the next 25 years. Some of the issues included are in relation to: the development of the high strength bolt and cable reinforcement practices widely adopted today and the contrast between stiff and soft systems; a focus on local detail, at the expense of understanding regional stability concerns; dramatic improvements in the use of, and systems available for underground geotechnical instrumentation and monitoring; some of the ground control management trends, including occupational health and safety concerns, availability of suitably trained staff and legislative requirements; the opposing approaches of the empiricists versus the numerical modellers ? is there some middle ground?

Jan 1, 2006

By J. Tremolada

El presente trabajo señala las bases y resultados que favorecen la recuperación del oro cuando se incrementa la concentración de oxigeno disuelto en la solución lixiviante. En ese sentido, el oxígeno es el agente que incrementa la disolución del oro, y el cianuro, su medio de transporte. Asimismo, aumentar la cantidad de oxigeno disuelto en la solución cianurada de riego mediante el uso de venturis (dispositivos que aspira aire del medio ambiente) logra soluciones cianuradas con concentraciones de oxígeno más altas, de forma se lograría una mejora en el proceso de la extracción del oro.

Sep 14, 2009