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By J. A. Hudson, D. L. Millar

Paper presented at a meeting on: Artificial intelligence in the minerals sector, held in Nottingham, UK, 20 April 1993 (original title: Rock engineering system performance monitoring using neural networks.) Synthetic and analytical approaches to objective-based design of rock engineering projects are discussed. Rock masses are considered as complex dynamic systems with components that concurrently interact with each other and their environment. The existence of a rock engineering system canon (i.e. a set of systems governing rules) is proposed. Its possible components are highlighted and an application is demonstrated using a "rock mass automaton" designed to simulate dynamic heat distribution in rock. In the example given, the canon implements the basic result from probability theory applied to the thermodynamics of solids. Rock engineering system performance is reduced to the mapping of the output of a rockmass to varying input (design) options, within the state space of the systems model. The Kohonen Self-Organising Map provides an extremely useful analytical tool to reduce the hyper-dimensionality of rock engineering system behaviour. Further, the hyper-dimensional state vector is mapped "quasiconformally" such that the neural map tends to spatially organise similar input state vectors, facilitating interpretation of rock engineering system behaviour (performance monitoring). Work is reported on the development and validation of the automation as a basis for an internal representation of the rock mass bahaviour. The results are reported of simulations compensating for the uncertainty of the exact mechanisms operating within the rock mass, using additive noise with the input state vector in the training stages of the self-organising map implementation. Initial work on adopting Grossberg's Adaptive Resonance Theory neural network architecture for classification of rock engineering systems behaviour is also presented

Apr 1, 1994

By S. H. Logan

The present discussions throughout the civilized world on the subject of gold for monetary purposes may seem due to general economic conditions during the past year. But for some years previously a small group of authorities had warned the world against the continued disregard of an equitable distribution of existing gold reserves, and had urged the necessity of keeping the supply of new gold equal to the monetary demand, which, according to world production and trade figures, increases on the average about 3 per cent per annum. In 1927, Sir John Aird, the President of The Canadian Bank of Commerce, stated that the United States could spare a billion dollars of the supply it then held, 4 ½ billion dollars. About a year and a half ago the Professor of Banking and Currency in the University of London, Mr. T. E. Gregory, said, "If the world finds it impossible to modify its habits so far as to make an organized effort to economize gold seem less Utopian, it must be prepared to pay for its bad habits, in this and other respects, by a possible loss of material welfare." These clear-cut statements were not heeded, perhaps for one reason because most countries were in the flush of prosperity, and making such great demands upon the mining fraternity for industrial materials as to distract attention, at least to some degree, from gold mining. Now the world knows it faces serious problems, first, of making? fully effective its present monetary reserves, which, although badly distributed, are as a whole ample for the needs of the present, and secondly, of preventing a shortage in the supply of new gold, one that may come within the next few years if the present sources of supply are not enlarged, and if there is no marked change in the technique of gold production.

Jan 1, 1931

By J. Hendry, K. Brady, J. Yorzyk

Drawing from the experience of nickel, copper, aluminum and mineral borates, this paper illustrates the business value that the mining, minerals and metals industry as a whole can gain from applying life cycle assessment (LCA) to products and operations. Through the use of case studies, the paper explores how companies and industry associations have used LCA to their advantage: from evaluating capital investments, meeting customer information needs, supporting new product applications, and developing credible marketing information on the environmental performance of their products. It also explores the dynamics of LCA adoption and integration within companies, and provides recommendations to further strengthen institutionalization of LCA.

Jan 1, 2010

By J. W. Paul

A superintendent is one who has the oversight and charge of some organiza- tion or enterprise, with porer of direction. The superintendent of a coal mine is the official who is in general charge of conducting the operation of the nine for the purpose of producing coal; he is accountable to his superiors for all matters that relate to the cost of production and safety in operation, ed under him are all the underground officials and other personnel making up the mine organization. The responsibility of the superintendent covers all the principal phases of mining, purchases of materials, issuance of supplies, accounting, and upkeep of the property and equipriont. In a broad sense, the superintendent must view his job as embraced under four gneral heads: (1) Construction, (2) instruction, (3) supervision; and (4) discipline. The degree of efficiency with which each of these phases of his work is conducted is a measure of the safety factor which the superintendent injects into his job. Injury to workmen and damage to property may be due to neglect of one of these general headings; as for example in the collapse of a scaffold there has been faulty construction which may be found upon investigation to have been the result of faulty instruction or lack of instruction. It may be that the condition of the scaffold was not ascertained in advance of its collapse through faulty supervision, or the discipline of the workmen had been neglected.

Sep 1, 1930

By Ferenc Molnár, David H. Watkinson

Abstract - Cu-Ni-PGE footwall ore deposits were studied in the McCreedy East and Whistle mines along the North Range, and the Lindsley and Little Stobie mines along the South Range of the Sudbury Igneous Complex. The footwall ores in these localities differ from typical magmatic Fe-Ni-Cu- PGE deposits in the Sudbury mining camp: they have higher Cu/Ni ratios, higher PGE content, veinlike appearance and ubiquitous association of ore with hydrous silicates. Results of comparative fluid inclusion petrography and microthermometry of footwall ores indicate that high temperatures (300°C to 480°C) and heavy-metal rich saline (up to about 40 NaCl equivalent wt% salinity) fluids were associated with the formation of the PGE-rich footwall ores at moderately high pressures (around 2 kbars). However, several, possibly independent fluid circulation stages were also found at the different localities and there also are differences in detailed characteristics for ore-forming fluids especially comparing data from the North Range and the South Range. Thus, in addition to the high temperature and salinity of fluids, there are local variations in the nature of hydrothermal processes. These differences may be related to the diverse origin of fluids (magmatic, metamorphic, and formational brines) and their differing extents of interaction with the compositionally different footwall lithologies.

Jan 1, 2001

Australian coal mines have spent considerable capital on dragline improvements over the last two years. This has included ~$30 M on UDD conversions, >$20 M on new buckets, boom upgrades, electrical upgrades, etc. This is a natural part of the response of mining companies to technology and replacement programs. Capital expenditure is a normal part of the ongoing success of most companies. There is however, a tendency for some people to rely on the capital alone to provide the ongoing improvements in equipment productivity. Implementing new technology through capital expenditure is only part of the equation in continuous improvement. For 80 - 90 per cent of the year, the operator controls the productivity achieved by the dragline. Variation between operators is huge. The average standard deviation in productivity is 12 per cent and maintenance impact is over 40 per cent. Robbins 2003, states: Contrary to what we were taught in grade school, we werenÆt all created equal. Most of us are to the left of the median on some normally distributed ability curve. Further, he states: The issue is knowing how people differ in abilities and using that knowledge to increase the likelihood that an employee will perform his or her job well. There are two options for reducing variability between operators; improving operator ability and getting the machine to take over what the operator is doing (automation). Dragline automation will be discussed, however, this paper will focus more on the æhuman factorÆ and how to establish a dragline with minimum variability between operators.

Jan 1, 2005

According to the previous research, it is found that the thickness of cover is mostly less than 100 m for highwall mining system. However, for most of the Chinese surface coal mines, the mining depth is over 150 m; on the other hand, the shovel-truck is the most common mining technology. As a result, a lot of residual coal will be remained around end-walls. Considering these facts, the calculated methodology of highwall mining system under thick cover is presented in this paper. Meanwhile, numerical simulation of highwall mining system under thick cover was carried out. The outcome shows that the calculated methodology for pillar stability of highwall mining system under thick cover presented in this paper is acceptable. In other words, the highwall mining system is feasible to extract the residual coal around end-walls in Chinese surface coal mines. Thus, not only coal recovery ratio can be improved, but also can increase the production life of surface coal mines in China.

Jan 1, 2012

By M Ridd

The Pasminco Century Mine (PCML) is located 250 kilometres north-north-west of Mt Isa in Queensland. As one of the worldÆs largest zinc mines, PCML comprises mining and milling operations at Lawn Hill, concentrate filtering and shipping facilities at Karumba in the Gulf of Carpentaria, and a 304 km slurry pipeline connecting the two operations.Mineralisation at Century occurs in the upper part of the Lawn Hill formation and is comprised of siltstones, shale and sandstone. Pyrite occurs immediately above the mineralised sequence, and throughout the footwall carbonaceous shale forming the lower proportion of the deposit. Zinc predominantly occurs as sphalerite (ZnS) and lead as galena (PbS). These sulfides are very fine-grained and may oxidise rapidly upon exposure. The pyrite, sphalerite and galena are the main potential sources of acid rock drainage (ARD) or heavy metal leachate at the mine site.To minimise the generation of ARD in the waste rock dumps, they are constructed in a specific manner and waste rock is classified into the following three classes based on competence and acid forming/consuming capabilities:Class 1: Competent rock, non-acid forming or acid-consuming material. Class 2: Non-competent, non-acid forming or acid-consuming material. Class 3: Acid-forming material. The generalised Waste Rock Dump Design for current operations comprises an outer zone of Class 1 material and inner zone with Class 2 and 3 material. Limestone is the Class 1 material used for both its structural support and acid neutralising capacity. Reserves of limestone at the mine site are limited. Net acid generation (NAG) tests confirm that a mix of limestone and shales can be net acid consuming.Field based and laboratory based trials have been established at PCML to quantify blending levels of limestone and shale that will produce leachates both neutral in pH and low in metal/salt concentrations. This paper will discuss the first six months results (of a two-year sampling program) from the trials.

Jan 1, 2004

By Frederic Masse

With widespread acceptance in the market place, many engineers are choosing ground improvement techniques to provide suitable foundation subgrade at sites that would have traditionally required deep foundations. This paper discusses the Controlled Modulus Columns (CMC) ground improvement technique and some case histories highlighting the use of this technique for retail development sites. CMC are a sustainable and cost-effective ground improvement technology that transmit load from the foundation to a lower bearing stratum through a composite CMC/soil matrix. The CMC installation is also an attractive option from an environmental perspective because it utilizes reverse flight augers, which displace the soil laterally. This installation technique achieves two goals: it densifies the soil around the CMC, which improves load transfer into the element and avoids spoil and its disposal. Through the introduction of two cases histories, we will present the key benefits of the CMC technology. Each case history will clearly illustrate how a CMC solution can reduce the overall cost of a project when compared to a more traditional type of deep foundations. They will also show how the use of CMCs has benefits that relate to the overall sustainability of the project. While CMCs are an attractive financial and sustainable option, they have also demonstrated that the performance of the system is comparable to that of deep pile foundations. Because CMCs are a relatively new technology many potential users are not aware of its benefits. While we discuss the use of CMCs to support buildings in this paper, CMCs also have been used for a variety of other applications including foundations for tanks, mechanically stabilized earth (MSE) walls, and embankments

Jan 1, 2011

By M. Howe

This is a study of the impact of cyanide from mining waste on riparian communities, primarily vegetation, near Whitewood Creek, down-stream from Homestake Gold Mine in Lead, South Dakota. Cyanide is used in gold processing and the effluent, until fairly recently, was discharged directly into Gold Run Creek which empties into Whitewood Creek. Vegetation, soil, and water were collected from four different sites over a six month period, and samples tested for cyanide concentration. Data indicate a relationship between cyanide in soil and its uptake by certain plants, also, that the Homestake cleanup effort has made the stream viable again.

Jan 1, 1983

By P. R. A. Andrews

"A sample of flotation feed from Bakertalc Inc., High water, Quebec was subjected to flotation evaluation to improve the recovery of talc. A number of alternative frother/collectors and depressants as well as flotation parameters including pH, conditioning time, frother/collector concentration and pulp density were assessed. In addition, the possibility of using a size coarser than that currently employed for flotation (95% minus 50 um) was investigated.As far as possible, a laboratory duplication of the present circuit arrangement was folio wed so as to minimize the cost of any changes. The best results obtained were a concentrate analyzing 95.96% acid insol for a recovery of 65.98% after four stages of cleaning. With recirculation of cleaner tailings, the recovery would be higher.The possibility of using an alternative method, based on the natural ability of talc to float unaided by a frother/collector, was briefly explored with encouraging results.IntroductionBakertalc lnc ., located in the eastern townships at Highwater, Quebec, Is approximately 140 km east of Montreal near the Vermont, U.S. border. Originally called Baker Mining and Milling Co. Ltd., it has produced pulverized talc products since 1938(1 ), although records show that talc was mined in the area as early as 1871(2). Feed to the mill originally was obtained from local deposits, but since 1952 the van Reet mine near south Bolton, approximately 25 km from Highwater, has been the source of ore .In 1957 a Raymond high -side roller mill was installed which enabled production of a greater range of talc products and, in 1960, new crushing equipment and a dryer were added. Other additions to the mill were the introduction of wet magnetic separation, although this was later discontinued, and flotation to produce high-grade talc concentrates."

Jan 1, 1985

By J. R. Hunter

The present is rooted in the past. This is particularly true in the case of mining operations. Coal mining in the United Kingdom is considered an old Industry comprising today 246 Coal Mines many of which have worked coal reserves in their locality for over 100 years. More than half the current producing mines lie in the Yorkshire and Midlands coalfields. They are in the oldest age group and produce 70% of the Industry's output. Some 50% of the remaining U.K. workable reserves amounting to approximately 98,000 million tons are still available to these regions. Fig. 1 Over the past two decades a gradual erosion of demand for coal in the U.K. has virtually halved the Industry's capacity. The number of Mines has reduced by 53% during the past 10 years. Productivity has increased by some 42% mainly through improvements in the central coalfields which has enabled costs to remain broadly competitive with oil.

Jan 1, 1976

By R. G. Cawthorn

The vertical distribution of platinum-group elements (PGE) in the Merensky and UG2 chromitite Reefs is highly variable, but does follow certain general patterns that allow the testing of geological models. In the Merensky reef, historically popular geological representations and interpretations have suggested that the mineralization occurs in a pegmatitic pyroxenite bounded by two chromitite layers. However, there are now enough published exceptions to this relationship to expose its fallacy. The vertical distribution of the PGE depends largely upon the separation between these two chromitite layers or the absence of one chromitite layer. Where separation is small or only one chromitite layer is present, there is considerable PGE mineralization in the footwall below the pyroxenite and lower chromitite layer. With increasing separation between the two chromitites, the mineral¬ization occurs progressively higher in the succession, and tends to track the upper chromitite layer. The view presented here is that the entire Merensky package is comprised of three events of magma emplacement, in which each has produced variable reaction with, and erosion of, the footwall, causing recrystallization of pyroxenite into pegmatitic pyroxenite. The magma then produced a chromitite layer followed by pyroxenite. Each chromitite layer is associated with some mineralization, which was extensively complemented by the subsequent formation of a sulphide liquid carrying PGE that trickled down through about 1 m of permeable crystal pile. The sulphide liquid formed after, not coincident with, the pyroxenite layers. The distribution of PGE in the UG2 chromitite shows up to three upward depletion sequences of PGE, also suggesting three events. The PGE are associated only with the chromite. The contribution from a sulphide liquid is considered to have been minimal for two reasons. Cu and Ni are extremely low in the UG2 which would not be expected if sulphides had been present. Also, by analogy with the Merensky, downward trickling of sulphides would have caused some PGE to be present in the footwall. There are some PGE in the footwall, but only where remnants of chromitite occur, and the hanging wall is lacking in PGE. In the northeastern Bushveld the UG2 chromitite is thinner than elsewhere, and there is a UG3 chromitite layer, not present elsewhere, that has a high Pt/Pd ratio. It is surmized that in the rest of the Bushveld the UG3 only appears to be absent because it has merged with the UG2 to produce the high Pt concentration at the top of the composite UG2. The non-accumulation of the package of pyroxenite-norite-anorthosite between the UG2 and UG3 in the northeastern Bushveld, which is not seen elsewhere, creates an interesting challenge to the formation of silicate layering in the complex. The mineralization in the Platreef is not addressed here. Keywords Bushveld complex, Merensky Reef, UG2 chromitite, geological evolution.

Jan 1, 2011

By Richard E. Steffens

The underground portion of Duke Power Company's Bad Creek Pumped Storage Project in northwestern South Carolina consists of a powerhouse cavern (132 m. long, 23 m. wide, 50 m. high), 407 meters of shafts and approximately 3615 meters of tunnel, both lined and unlined, with diameters varying from 4.2 meters to 9.0 meters. A case history is presented, including the early pilot tunnel exploratory work and how this affected design, the design of the project, and the excavation, rock support and tunnel lining work. Problems and experiences encountered during the construction are given. The effects of high horizontal insitu stresses in the granitic gneiss are discussed along with solution taken.

Jan 1, 1989

By Morton Macartney

FOR many years the developers or owners of worthy mining ventures in need of financing have found it almost impossible to obtain such financing under the conditions existing in most other lines of business. High rates of interest and unfair participation in profits have robbed the developers of much of their holdings, and have resulted in over-capitalization and many other like evils. When the general financial condition of the country is bad, this difficulty increases to a point where many operations must cease and hen are thrown out of employment. In 1.934 this situation had developed to such a point that Congress attempted to aid the mining industry. It first authorized the RFC to make loans to recognized and established corporations, individuals, and partnerships engaged in the business of mining, milling, or smelting of ores in June, 1934, limiting such authority to loans adequately secured, the security to consist of mineral acreage. The requirements of the law were stringent and of the 252 requests for loans received up to June 1, 1935, 35 were authorized.

Jan 1, 1936

By M. A. Trvits, M. Cummins, A. C. Smith, T. P. Mucho

This paper evaluates the effectiveness of remotely applied nitrogen-enhanced foam to aid in efforts to isolate and suppress a mine fire. The foam, in combination with a remotely-installed cementitious mine seal and a novel borehole pressure sampling methodology to determine the location of the suspected ignition source, was used to help control ventilation and inert the area surrounding the suspected ignition source by isolating it from oxygen. This allowed mine rescue teams to safely enter the mine, seal the area, and begin recovery operations to successfully return the mine to full production.

By K. G. Chipman

IN 1936, the Department of Mines and Resources was formed by the amalgamation of the former Departments of Mines, Interior, Indian Affairs, and Immigration. In the amalgamation, the Geological Survey and the Topographical Survey became the major divisions of the Bureau of Geology and Topography, which is a part of the Mines and Geology Branch which, in turn, is a part of the Department of Mines and Resources. The Topographical Survey was formed by combining the former Topographical Division of the Geological Survey and the air and ground mapping sections of the former Topographical and Air Survey Bureau of the Department of the Interior. The latter organization, previous to 1933, had been known as the Topographical Surveys Branch of the Department of the Interior. The amalgamation of 1936 definitely placed on the Topographical Survey the responsibility for the original mapping required for the development of our natural resources. The war has brought upon us the situation where all work has had to be in the furtherance of the war effort. With decreased staff and limited appropriations, the mapping on those scales which are directly concerned with the natural resources has been confined to the search for oil and strategic minerals. The reconstruction period will produce a different situation, with different problems. The past is behind us and it is necessary to prepare for the future. First, we should consider briefly a few general principles in the making and using of maps, then take stock of what we have, see what the needs are, and consider how we are to meet these needs.

Jan 1, 1944

By Marton A

The Readymix Group have a Quarry Improvement Program - 'Building in Quality (BIQ) which has many parallels to the ICI Explosives' total quality management - 'Quality Improvement Program' (QIP). Both companies have for some time recognised that the 'do it right first time' principle means less wasted effort and materials, that efficiency breeds profitability and so actively promote the quality culture. To install the principles and generate the culture requires considerable commitment and effort from the top down and invariably spreads to the suppliers and sub-contractors. Understanding the component processes involved with the quarry operation, analysis of those processes and gaining a breakdown of the cost of non conformance then allows the astute quarry operator to make the necessary changes to improve the process to realise profits. This paper outlines the steps in such a process and the profitable outcomes of the commitment to continuous improvement at the Nickol Bay Quarry.

Jan 1, 1994

Prior to the merger of BHP and Billiton, both companies had a keenfocus on improving their performance in health, safety, environment and community (HSEC) matters. This shared intent, albeit executed insomewhat different ways, provided an excellent foundation for the newCompany. During the integration planning phase, a team was formed toconsider the organisational design for consistently achieving world class HSEC performance. The design included the policy platform, resources, structures, standards and procedures to be implemented in the merged entity. A key aspect of the design was the fully integrated HSECManagement Standards. These Standards create the framework for theconsistent application of BHP BillitonÆs HSEC Policy at all of ourmanaged operations across the world. The Standards have their origin in similar frameworks adopted by BHP during the 1990s, as well as thewell-known quality related standards (eg ISO 14001). However, they areunique in that they combine all aspects of HSEC management into asingle integrated set of auditable standards. By combining these areas and integrating our HSEC Management Standards with other aspects of the æBHP Billiton WayÆ, we are establishing a holistic, line management driven improvement approach. Over time, the BHP Billiton Way will embed a systematic improvement philosophy that we expect will become a key source of competitive advantage. The HSEC Management Standards are consistent with ISO 14001,OHSAS 18001, the Australian Minerals Industry Code for EnvironmentalManagement and generally aligned with SA8000. While compliance withthese external standards ensures that a systematic approach andimprovement plans are in place, BHP BillitonÆs HSEC Standards gofurther to include minimum performance requirements that reflect theintent of our HSEC Policy. Therefore, implementation at site levelensures that robust systems are in place to implement our Policy and that accreditation can be achieved to external standards if required.To assess implementation of the HSEC Management Standards anaudit system has been designed which incorporates both self-assessmentand peer review. Each site is required to undertake an annualself-assessment of compliance with the Standards using a commonassessment protocol. Every three years a peer review is conducted at each site to confirm the results of self-assessment and to provide a means of sharing knowledge throughout the Company. The review teams are composed of line managers and HSEC professionals from around theCompany, representatives of our joint venture partners and independentspecialists as required. The Company has committed to public reportingof the audit results through our annual HSEC report and this is reflected in our published targets. From a wider perspective, as we in the resources industry strive tocollectively raise our HSEC performance and reputation, there may be arole for industry based HSEC Management Standards complemented bya level of independent review.

Jan 1, 2002

By C. J. Johnson, C. J. Bise

"IntroductionCoal extraction by continuous miners (CM) is currently the most common underground method in the US industry and accounts for slightly more than two-thirds of the nation· s deep mining production (National Coal Association, 1987). Even if longwall mining should become more commonplace, it can proceed only af1er ventilation and access entries have been driven by CMs. Since an area of concern continues to be the effects of the dust generated on the health of mineworkers, this paper discusses the relationship between the elemental composition of mining-generated airborne dust sampled from the immediate ventilation return of a CM and laboratory-generated dust derived from channel samples taken from the mines.There are several potential contributions of this type of study to the coal mining industry. First after more fundamental knowledge of the causes of Coal Worker's Pneumoconiosis (CWP) is learned, the laboratory-generated respirable dust could be used to identify a potentially hazardous coal seam. Also, this study could possibly aid in understanding the fundamental causes of CWP by producing mining-simulated samples of coal dust that could be used in epidemiological studies.Further, assuming that there is no difference in the elemental composition of a drill-core sample and a channel sample from the same location a mining company could predict anew mine's respirable dust elemental composition In the immediate ventilation return by using exploratory drill core samples of the roof ,coal, and floor rock to prepare the laboratory dust. Ventilation engineers could then use engineering design and control measures during premine planning to reduce the incidence and severity of CWP by better ventilating the potentially hazardous coal seam. If this proper planning prevented any future changes to the ventilation equipment and mine design, much time and money could be saved.Scope of workTo investigate the variability of the chemical characteristics of respirable dust, airborne dust samples from eight underground coal mines located in the eastern and mid western United States were collected with eight-stage Sierra Model 298 Marple cascade impactors, as well as 25 channel samples of mined material. Each channel sample was removed from the middle of the coal face before mining occurred. Sampling of the mining-generated dust was conducted by Lee ( 1986) by sampling the entire working sections, primarily for characterization purposes, to obtain information on the locational variability of dust characteristics. Research performed for this study used the elemental analyses of the mining-generated dusts he sampled in the immediate ventilation returns of CMs."

Jan 1, 1989