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This paper highlights the agricultural sector's primary concerns with mining in New Zealand: the information gap, land rehabilitation and compensation. It suggests how these issues can be resolved between the competing land uses in the interests of New Zealand.

Jan 1, 1981

By R B. Turner

The authors have studied and analysed many mineral resource and related projects in Australia. These studies have lead them to conclude that the past performance of many project developers does play a major part in any external financial investment for new or expanding resource based projects. In this paper the authors look particularly at the influence of parties outside the direct control of developers and the effect of' these parties on projects and conclude with a number of points as guidelines for potential project developers.

Jan 1, 1980

By R. Scott

This article describes and evaluates the establishment of Kuyasa Mining including the search for a suitable deposit, the ongoing lack of finance, and market constraints. Despite the dramatic initial growth and success of their Ikhwezi Colliery near Delmas, Mpumalanga, Kuyasa?s experiences offer some sobering arguments for significant changes to mineral rights ownership, the attitude of financial institutions and government policy if South Africa is to have a dynamic and successful junior and small-scale mining sector.

Jan 1, 1998

By Sergio Neves Monteiro

The efficiency by which an applied load is transmitted through the composite structure depends on the strength of the interface between the matrix and the second phase. In fiber reinforced composites, the interfacial shear stress plays a major role in the composite capacity to support the applied load. This interfacial stress can be obtained by means of pullout tests using the fiber embedded to a certain length in a socket of the matrix material. In the present work, pullout tests were performed to evaluate the interfacial shear stress of ramie, a relatively strong natural fiber, reinforcing polyester matrix composites. The general result permitted to calculate a critical length for the ramie fiber embedded in polyester resin. From this critical length, the value of the interfacial shear stress was calculated. An interpretation of this result together with SEM observation displayed a relatively weak bond between the ramie fiber and the polyester matrix.

Jan 1, 2010

By David Meadows, John Starkey

"As part of the ongoing project development for the Tenke Fungurume Copper-Cobalt Project in the Democratic Republic of Congo, Phelps Dodge Corporation has examined methodologies for determining the size of grinding mills to support a 7000 mtpd operation. Six samples were tested by Hazen Research, Inc. (HRI) to obtain the JK parameters using the JK Drop Weight Test, standard Bond crushing, and rod mill work indices, abrasion indices and by Dawson for Bond Ball Mill Work Index tests using crushed feed, and Standard Autogenous Grinding Design (SAGDesign) Tests, patented by Outokumpu. (See reference 8 below).The comparison of these results gives context to how the various measurements relate to each other and how they can be used to obtain an accurate design for the grinding mills required for the Tenke Project. This is the first published direct comparison between JK Drop Weight, standard bond work indices, and SAGDesign test results. The SAGDesign test includes a SAG test followed by a Bond BM Wi test done on SAG ground material.INTRODUCTIONAfter the presentation of the paper “SAGDesign Testing – What It Is and Why It Works” at the recently concluded SAG 2006 Conference in Vancouver, a question was asked about how SAGDesign ore hardness measurements compared with other comminution tests, specifically the JK Drop Weight Test and the parameters that are derived from such testing. At that time it was noted that a paper was being prepared for the CMP Conference in January to show how various ore hardness measurements compare with each other when done on the same samples.This paper will therefore present the first such comparison using test results from the Phelps Dodge Tenke Fungurume Project where six composite samples were examined by the tests noted below. A seventh sample was tested at Dawson but not at other labs. The tests were done at four different laboratories listed below and included the tests shown."

Jan 1, 2007

By T. S. Golosinski

Introduction Typical dragline rigging includes several sets of ropes: hoist ropes, drag ropes, dump ropes and boom suspension ropes. The drag and hoist ropes contribute most to the dragline operating cost. Both work in very difficult conditions and wear out rapidly. As a result, frequent rope changes are required resulting in substantial cost and productive time loss. Although performance of rigging has a profound impact on dragline efficiency, there are no common, industry accepted standards related to its selection, operation and maintenance. Little information on the subject is available and the practice differs widely throughout the industry. The performance of drag and hoist ropes depends on: •rope construction that should closely match requirements of the specific application, rope operating conditions and its maintenance and • correct definition and application of the rope discard criteria so that full advantage of the rope can be taken without endangering safety of its operation. This paper reviews the present practice related to all these factors. Its findings are based on the wide survey of the present industrial practice. Field survey In total, 33 North American dragline applications were surveyed of which 17 were Bucyrus-Erie machines, 10 were Marion and six were Page (now P&H). Most of the draglines were stripping overburden in coal mines, but the survey also included some unique applications such as phosphate mining in Florida and oil sand mining in Alberta. Hoist drive power of the surveyed machines varied from 300 to 7775 kW (400 to 10,400 hp). Drag drives varied from 300 to 5815 kW (400 to 7800 hp). Boom lengths varied from 37 to 110 m (120 to 360 ft). Bucket sizes varied from 5 to 96 m3 (6 to 115 cu yd). The hoist and drag ropes installed on the surveyed machines were supplied by 10 rope manufacturers and differed widely in type and construction. Most common rope strand constructions included standard strands, Seale, Warrington, Warrington-Seale and Filler-Seale. Results of the survey [ ] Working conditions Working conditions of hoist and drag ropes are quite different. The first cope primarily with bending on rope drums, point sheaves and deflection sheaves, and with tension force imposed by the bucket and its load. The drag ropes are exposed to severe abrasion at the pit crest, and to severe bending and crushing at fairleads, all while coping with tension forces imposed by resistance of the bucket to dragging. Bending of drag ropes at house rollers and at rope drums is of minor importance for their performance. Differences in working conditions result in different wear patterns, which make it feasible to install discarded hoist ropes to further serve as drag ropes. The hoist ropes wear primarily due to fatigue breaks of wires, while the drag ropes are subject to severe abrasion of outside wires, rope deformation and internal wire-strand breaking. The last is often indicated by the reduction of rope diameter. The summary of working conditions for the surveyed draglines is shown in Table 1. For simplicity, Table 1 does not include the data on rope bending at the fairleads, nor at the deflection rollers and house rollers. Similarly, Table 1 does not include the data on drag rope bending (other than that on the rope drum), as its influence on rope life is insignificant in view of severe abrasion and internal wear taking place elsewhere. The following abbreviations are used in Table 1: [D - diameter of rope drum. DP - diameter of boom point sheaves. d - rope diameter x - mean value of the measured parameter. s - standard deviation of x B/d - average bending ratio of ropes B/d =(D+ DP)/2d n - operational safety factor of the rope (rope stength) x (number of ropes) n(bucket load + bucket weight)] In terms of D/d ratio, the working conditions of hoist and drag ropes are similar to that in other related industrial applications. However, the safety factors of the dragline ropes are lower, which requires them to carry relatively large tension forces. The last explains the fact that the life of dragline ropes is low when compared to other industrial rope

Jan 1, 1995

As part of a comprehensive risk analysis which was carried out into the effectiveness of the water barrier between South Deep and Randfontein Estate mines, the potential threat posed by large seismic events was assessed. The study covered several aspects. Firstly, an estimate of the maximum credible earthquake was obtained from a probabilistic analysis of the regional seismicity of the previous 25 years. Allowance was made for ?reservoir-induced? effects by increasing the estimate of the size of the maximum credible earthquake from ML= 5.1 to ML= 5.5. Based on available knowledge of the geological structure, the possibility of such an event occurring in the vicinity of the barrier pillar was estimated. The possibility of substantial damage to the barrier rock mass, resulting as a consequence of a large event, was assessed. The likely damage to the concrete control plugs installed in five tunnels that penetrated the barrier, which might result from a ?near-miss? by the largest possible seismic event or from a ?direct hit? by a smaller event, was also considered. It was concluded that there was a negligibly small possibility that the maximum credible earthquake could occur close enough to the barrier, and in such a manner, as to cause any damage to it or to the plugs in the tunnels passing through it. The possibility of serious plug damage occurring as a result of a ?direct hit? by as maller event was slightly greater, but still sufficiently remote as to be of no practical concern at all.

Jan 1, 2006

By G. Bellefleur, K. Stevens, E. Adam, D. Synder, G. Perron, C. Müller

The Downhole Seismic Imaging consortium was initiated by the Geological Survey of Canada and three Canadian mining companies to assess the usefulness of borehole seismic techniques for the exploration of massive sulphide deposits within areas of steeply dipping stratigraphy. Field tests were conducted over two sub-economic massive sulphide deposits located in Norman West, Ontario, and Halfmile Lake, New Brunswick, using various shot configurations and a three-component borehole receiver array. The Norman West deposit, or structures associated with the deposit, produce detectable seismic reflections as far away as 1500 m. However, these reflections are difficult to distinguish from fault reflections and lithological contacts near the base of the Sudbury Igneous Complex. At Halfmile Lake, the rock properties are favourable for direct orebody detection. The Halfmile Lake deposit has a clear but relatively complex seismic signature on the downhole data, showing not only P-wave reflections, but also strong reflected S-waves and modeconverted waves. Such prominent S-waves and converted waves have not been recognized previously in borehole or surface seismic data acquired over massive sulphide deposits. These waves add complexity to the interpretation but provide additional imaging capabilities. Reflected S-waves and converted waves should be considered when designing seismic surveys for mineral exploration.

Jan 1, 2004

The overwhelming weight of scientific opinion indicates that human activity is having a discernible and negative influence on the earthÆs climate system. The Australian Government, together with about 100 other nations, has accepted the findings of the Intergovernmental Panel on Climate Change third assessment report, released in 2001. This report was prepared by several hundred eminent scientists from all over the world, from various scientific disciplines and with differing opinions on global warming. The IPCC third assessment report contains a series of relevant, significant conclusions; for example, it finds that there is an increasing body of observations that gives a collective picture of a warming world and other changes in the climate system. Global average surface temperature increased over the past 100 years by about 0.6¦C. This may not seem much, but in the 900 years beforehand, the EarthÆs temperature remained relatively stable. The 20th century was the warmest of the past 1000 years in the northern hemisphere (there is much better information available from the northern hemisphere than the southern hemisphere). The 1990s were the warmest decade of the millennium in the northern hemisphere and 1998 was the warmest year. Although many factors influenced the EarthÆs climate, scientists are confident that greenhouse gas increases were the main factor contributing to global warming in the last 50 years of the 20th century. Increases in carbon dioxide, methane, troposhperic (lower atmosphere) ozone, halocarbons and nitrous oxide have all contributed to global warming. Combating climate change cannot be done without the cooperation of industry and the community at large. It is important that Government and industry work together to achieve greenhouse gas abatement while ensuring continued economic growth. The cause of the problem û the generation of greenhouse gas emissions û lies at the heart of the structure and size of modern economic activity. Greenhouse gas emissions are embedded in our way of life from our energy consumption patterns to the basic production of food. Moreover, the costs of the impacts of climate change to the earth will be potentially revolutionary, not merely evolutionary. It is in this light, acknowledging both the seriousness and nature of the problem before us that I want to reflect on the key drivers in the international climate change negotiations. A consideration of the past, present and future from what I see as the mid-way point in the process. In 1997, Parties agreed to adopt the Kyoto Protocol, which sets out mandatory targets for greenhouse gas emissions for developed countries.

Jan 1, 2002

By A. H. Mumin, A. K. Somarin, K. S. Oran

"Synvolcanic structures played a fundamental role in the genesis, morphology, and siting of volcanogenic massive sulfide ores and associated hydrothermal alteration in the Archean South Sturgeon Lake caldera complex. The most voluminous and persistent hydrothermal venting and massive sulfide deposition occurred along synvolcanic rifts and grabens associated with faults and tectonic fissures that created permeable fracture zones deep enough to access the underlying hydrothermal reservoir. The type of fracturing is highly variable and changes with the composition, competency, degree of consolidation, and alteration of host rocks. Synvolcanic structures and fracture styles also vary according to the amount and type of tectonic movement, including extension-related collapse, shearing and faulting perpendicular to the principal direction of extension, and orthogonal faulting and shearing. Permeable conduits were created by tension fracturing along fault zones, brittle deformation at the intersections of orthogonal faults, and by extensional fractures in stockworks. In texturally uniform footwall rocks, the distribution of alteration zones was controlled by the morphology of the structural conduit. In rocks with vertical and/or lateral facies, permeability, and competency changes (e.g., Lyon Lake graben), there was an additional stratigraphic control over fluid migration. Some crosscutting synvolcanic structures, alteration zones, and intrusions appear as stratiform units at the present erosion surface due to regional deformation and the present attitude of the volcanic stratigraphy.Hydrothermal mineral assemblages (e.g., quartz, carbonates, chlorite, pyrite, chalcopyrite) infilling structurally induced fractures provide good evidence of fluid migration pathways. However, mineralogy can vary significantly according to the fluid characteristics, host rock geochemistry, and subsequent metamorphic history of the area.Clearly, one of the best methods for locating volcanogenic massive sulfide deposits is to delineate the attitudes of synvolcanic structures, and explore those that show evidence of associated high-temperature hydrothermal mineral assemblages. Excellent exploration targets occur where synvolcanic structures with hydrothermal alteration intersect paleo-seafloor horizons."

Jan 1, 2007

How Particles Stick to Bubbles - The Influence of pH and Hydrophobicity in Flotation

Sep 13, 2010

By Alex Chapman, Cam Thomas, Bryan Karney

"During the early summer of 1989, Ontario Hydro removed a concrete portion of the North Channel Dam at Crystal Falls Generating Station by blasting and excavating in marine conditions. Because of the severity of underwater blasting and because the site was in close proximity to the replacement dam, there was concern that hydraulic shock waves generated by the detonation could damage either the new dam or its control structures. This paper examines the data associated with the hydraulic shock waves generated by underwater blasting, and studies the effectiveness of an air curtain in reducing the peak pressures. In previous trials using the air curtain technique, a rule-of-thumb factor was used to estimate that only 10% of the original pressure pulse would propagate across the air curtain. However, this value had little basis in theory. A theoretical formulation of the problem by Karney in 1989 indicated a provisional value of 0.18 for this factor, but was heavily dependent on confirmation from in-field testing. Data provided by Ontario Hydro from an actual blasting procedure indicate that a more conservative value of 0.32 may be more appropriate. Thus.although the air curtain did provide considerable reduction of peak pressures, the data at Crystal Falls indicates its performance was below the anticipated level. However, due to problems with the instrumentation and some inconsistencies in the resulting data. it is recommended that this value be further refined as additional data become available."

Jan 1, 1992

By Karim El-Ouassiti, Marc Minville, Stéphane Chabot, Claude Bazin, Valérie Ouellet

"Alumina is the main source of aluminium and it is extracted almost exclusively from bauxite ores found in the Southern hemisphere. Clays are abundant minerals that contain from 15 to 40% w/w of alumina from which it can be extracted by various processes. This paper reviews the processes used for the extraction of alumina from clays and discusses results obtained with a clay sample from the Murdochville area in the Quebec Province. The application of a conventional process to this clay did not yield an acceptable recovery although smelter grade alumina was produced. A modification to the process allows increasing alumina recovery from 85% to more than 92%. The application of the improved flow sheet to other alumina carriers failed to yield comparable recovery, showing that an optimum processing path for the recovery of alumina should be found for individual clay materials.INTRODUCTIONMost of the aluminium smelters are fed with alumina extracted from bauxite found in the Southern hemisphere. Bauxite is processed by the Bayer process that uses a caustic leach of the ore. In the middle of the century, the US Bureau of mines, motivated by the fear of an alumina delivery disruption, conducted several research projects aiming at producing alumina from non bauxitic ores. These projects led to the development of various acid leaching processes (Habashi, 1993). The sulphuric and hydrochloric acid leaching processes were brought to pilot plant evaluation (Bengtson, 1979), while nitric and other leach liquors were tested in the laboratory (Phillips and Wills, 1982; Habashi, 1983). Although clays are abundant and inexpensive minerals, the studied processes remained uncompetitive with the alumina extraction from bauxite (Hudson, 1987 page 42; Peters et al., 1962) for which reserves are estimated to support alumina production for the next 50 years (Oye et al., 1999). On the other hand, the local extraction of alumina from clays could significantly reduce the transportation costs of alumina to smelters and provide an alternative source of alumina supply from the Southern hemisphere countries. Also, the extraction of secondary products for some types of clay (Nasyrov et al., 1999) containing significant amounts of potassium and sodium could provide an additional return that may improve the economics of alumina production from clays."

Jan 1, 2005

By D. Stone

"The Beal Mountain mine near Anaconda, Montana, is an interesting case history of a mine that has continued operations despite several large pit wall failures over a period of approximately 10 years. The largest event involved some 3.9 million tons of rock that has moved steadily at a rate of about 0.05 ft/day since 1992. This paper documents the geotechnical instrumentation and monitoring programs implemented at Beal to provide the company with a comfortable baseline that supported ongoing operations. The success and failure of a variety of stabilization measures will be discussed, along with typical instrumentation responses for several significant events. The success of Beal Mountain serves as a good model for mines faced with serious geotechnical challenges."

Jan 1, 2002

By Jacek Paraszczak

Application of teleoperated and automated mobile equipment in underground metal mines represents a promising avenue to overcome some of the challenges facing the industry. This paper addresses the issues of overall effectiveness of the autonomous loading and haulage equipment in comparison with conventional man-operated machines. It overviews and discusses the factors affecting availability, utilization and production rate. It puts an emphasis on some problems and risks not present in conventional man-operated systems, as well as their character and criticality. It stresses the need to analyze the factors affecting OEE of the autonomous equipment more in-depth than it has been done up to date and to take them into consideration at the stage of feasibility studies. The paper concludes with some recommendations and indicates the directions of the future research in this field.

Oct 1, 2009

Geophysical surveys are currently being carried out over mineral prospects all around the Pacific Rim. Many of these surveys are successful in locating mineralisation in porphyry intrusives, mesothermal environments, and epithermal vein systems. A number of examples of surveys in Indonesia and Papua New Guinea are presented, which show the successful application of various geophysical techniques to the discovery of mineral deposits on the Pacific Rim.

Jan 1, 1999

By J. Allan Tice

In the past fifteen to twenty years, the use of drilled piers to support high capacities in coastal plain deposits has become more and more common. With improved construction techniques and better understanding of pier behavior, drilled shafts with capacities of 200 to 500 tons are not unusual. The purpose of this presentation is to review several drilled pier installations from North Carolina to north-east Florida as a means of illustrating the different types of design concepts and installation techniques which are presently being used. ACKNOWLEDGEMENTS The information in this presentation was obtained from work performed by many individuals and companies. The section on limestone socket caissons in South Carolina is an abridged version of a paper prepared by Rob Smith and Neil Gilbert of Law Engineering's Charlotte, North Carolina office, and is used with permission. The section on pier installation in northeast Florida is an abridged version of a paper prepared by Kirk Mcintosh, Tom McDaniel, and Randy Knott of Law Engineering's Jacksonville, Florida office, reprinted here with permission. Additional data discussed in this presentation has been obtained from Farr Foundation Company, McKinney Drilling Company, and Peterson Drilling Company.

Jan 1, 1988

The latest outcome of science is that aII bodies are composed of vibrating atoms or molecules. In almost all mineral bodies when changing from the gaseous or liquid condition to the solid, if the vibrating molecules are allowed free play, they arrange themselves in a symmetrical manner, and at a definite angle to each other: This angle varies with each system of crystallization. In a great many bodies this process may be brought about artificially, and the growth of the crystal watched. The most common method is to dissolve some substance in water or some other liquid, on slowly evaporating the liquid, the substance dissolved will solidify and the molecules will arrange themselves in their particular crystalline form.The element carbon crystallizes in two forms; as graphite in the form of a short six-sided prism', and in the diamond generally as the octohedron in the cubical system of crystallization. Orystalline bodies, as a rule, have plain faces but what is remarkable in the diamond is that in a great many cases the faces are rounded. Its great beauty as a gem when cut, and the high artificial value placed upon it by fashion, as well as its value as a cutting and boring instrument-it being the hardest body in nature-has caused many attempts to be made to form it artificially. These attempts have met with fair success as a scientific experiment, but as a commercial speculation they have been a complete failure. The most noted of these experIments was carried out by Mr. Hannay, of Glasgow.Paraffin spirit with lithium was submitted td prolonged heating in strong wrought-iron tubes securely welded. In most of the experiments the tubes exploded; but in a few cases the experiments were successful, and on cutting open the tubes small crystals of diamonds were found embedded in a black mass.Despretz produced minute diamonds under the influence of a powerful electric current from coal.

By Dean Lindsay, Inna Dymov, Mariam Melashvili, Jim Smolik, Chris Fleming

"This paper presents results from the proposed cyanide detoxification circuit for Seabridge Gold’s KSM project. The proposed flowsheet uses a two-stage CCD (counter-current washing/decantation) circuit to transfer the flotation products CIL(carbon-in-leach) barren solution to a SART process (Sulphidization, Acidification, Recycling of precipitate, and Thickening of precipitate) to recover copper and free cyanide from the copper cyanide complex. The SART barren solution is then treated by an AVR process (Acidification, Volatilization of HCN gas, and Reneutralization) to concentrate the cyanide that was liberated in SART for recycling to leach. The washed CIL barren pulp (the CCD underflow) is treated with the SO2 /Air process to oxidize residual cyanide.The goal of this complex flowsheet is to recover and recycle as much cyanide as possible and produce a final effluent containing less than 0.5 mg/L copper and CNWAD at the lowest cost. The SO2/air process is capable of achieving low residual CNWAD (<1 mg/L) in the final product, but the persistence of aqueous copper above the target level has been detected in the treated solution in some instances. The expected high concentrations of copper and cyanide in the KSM CIL barren ( >200 mg/L each species) and the difficulties this might create for the SO2 /air process was a key factor in the decision to consider including the washing, SART and AVR steps in the project flowsheet.The target concentrations of CNWAD and Cu were readily achieved after aging the SO2 /air treated pulp, as would occur in a tailing or polishing pond. This suggests no additional treatment will be required to sustain low levels of these species in the final plant effluent."

Jan 1, 2015

By Colin Curtis

In recent years, Manchester Airport has undergone expansion including the construction of a second runway, a new terminal building (Terminal 3) and extensions to the existing Terminal 1. Manchester is Britains third largest airport and ranked 20th in the world for international traffic. Arup (Manchester) was engaged as consulting engineer in a multi-disciplinary role for the terminal works. Part of this was a geotechnical commission including site investigation and pile design followed by supervision. This paper reviews the piling for the old, new and terminal extensions. In total, five pile types have been utilised over the years. The original 1950&apos;s Terminal 1 was founded on driven cast in situ piles, with a later 1970&apos;s extension utilising rotary augured piles. The recent piling comprised continuous flight auger piles (CFA), driven steel tube and tripod bored; the latter in areas of restricted access or low headroom. The ground conditions are Made Ground over thin Alluvial and Glacial drift, in turn, over a generally weak to moderately weak gypsiferous mudstone. All the piles were socketed into the mudstone. In terms of the new CFA piles, quality control using the instrumentation monitoring was problematical, but a substantial static load and integrity test programme resolved pile performance. Part of the work is matching new pile performance with previously installed piles and the continued use of older piles with new loads. Research provided some data on the older piles, including some static load test data, which enabled back analyses of their design and likely behaviour. Differences in design methods, installation techniques and pile behaviour based on load tests will be discussed.

Jan 1, 2001