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By D J. Kilkenny

Work practices involved in shaft construction can be aligned with current industry standard operating practices. However, the working environment during conventional shaft construction introduces unique conditions which can not always be overcome by hard engineering controls. To provide an improved working environment, future shaft diameters will generally be greater than has historically been the case for the Australian hard rock mining industry. This paper aims to explore both what can be constructed from the contractors perspective, and how does an owner extract maximum business efficiency from an asset that in many ways is likely to be larger, more complex and more expensive than initially envisaged.Newcrest Mining Limited, or an associated company, has constructed two major shafts over the last seven years. In both cases, Byrnecut Mining, or an associated company, was the contractor engaged for the shaft sinking activity. The first is the 1127 m deep, 7.0 m diameter production and intake airway at the Telfer Gold Mine, the second is a 295 m deep, 5.5 m diameter split shaft at the Gosowong Gold Project in Indonesia that was primarily designed as both an intake and exhaust airway. Importantly both shafts are designed to provide emergency egress from the respective underground operations.From an Australian shaft sinking perspective, the construction of these two shafts resulted in the following learnings: •constructability is of equal importance to desired functionality;•allow six months of interactive design between the owner/engineer/contractor/regulator to get it right;•shaft sinking and equipping are intimately entwined, therefore engineering of both needs to be complete prior to any activity commencing; and•the mobilisation of both equipment and experienced personnel to a new shaft sink takes up to eight months.Shaft sinking is not extinct in the Australian hard rock mining industry. But, if you are considering constructing a shaft, approach it as a long life asset, front end planning to a high level of detail is required to unlock its full value. Think – plan – think and remember it’s going to take 12 months to get from the whiteboard to firing the first cut.

Mar 21, 2011

The Department of Mineral Resources has a statutory responsibility for mine site environmental management and control in New South Wales. The Department is focusing on an environmental management systems (EMS) approach, as a management tool to achieve æbest practiceÆ outcomes both within our own organisation and on mine sites. One of the DepartmentÆs tools is environmental risk assessment and management which incorporates the Mining, Rehabilitation and Environmental Management Process (MREMP). The MREMP was introduced many years ago in order to integrate the activities of key stakeholders who may have a material interest in the mine. The MREMP provides an ideal mechanism by which ædue diligenceÆ requirements and environmental management programs can be integrated into mining operations and lead to a sustainable post-mining land use.

Jan 1, 2002

By M. C. Bétournay

Mine site infrastructure for storage and delivery of hydrogen must be standardized and acceptable for routine and safe industrial use before fuel cell technology is adopted as a major power source. An initial study reviewed possible options for production, storage and delivery of hydrogen for underground equipment. The high level review included assessment of economic, operational, technical, and health and safety risks. Following this review, a subsequent theoretical study to select typical minesite infrastructure and for construction at an operating research mine is outlined.

May 1, 2007

By S. J. Kohut

Until recently SX-EW technology has only been used to produce conventional cathode for the cyclical commodity marketplace. Unlike electrorefining, SX-EW lends itself to the integration with the downstream manufacturing technologies for direct mine site production of value added products. The integration of SX-EW and downstream manufacturing results in the elimination of redundant process steps, the cost savings, and the access to value added product markets which can buffer the producer from swings in the cathode market. SX-EW production of copper powder and powder-based products has been demonstrated at the pilot plant level. The SX-EW process has been successfully redesigned to meet the more specific demands of engineered products. Challenges include the solution purity, the cell ventilation, the high current density operation and the product handling. Successful demonstration of mine site production of value added SX- EW products opens up new non-commodity marketplaces to the mining industry.

Jan 1, 1999

By A Markham

Stream diversions are a common feature of mine sites worldwide. From an operational perspective, a fundamental requirement of a stream diversion is that it should convey water flows between two points in a safe, controlled and predictable manner. On the other hand, rivers and waterways are naturally dynamic systems, and many of their natural values are achieved through their ability to alter their forms and processes over time in response to flow events - often in a potentially unsafe, uncontrolled and unpredictable manner. In order to ensure that diverted river reaches achieve the dual objectives of short-term operational stability and longer term physical equilibrium with surrounding landscapes, alteration of form and process must somehow be understood and incorporated into the design process. However, performance targets for waterways are not always easy to define and assessing what is good and bad in such variable systems can be difficult. This paper discusses the role of the stream diversion from the operational, environmental and regulatory/relinquishment perspectives, and how stream diversions must achieve physical stability in the short-term, but dynamic equilibrium in the long-term.CITATION:Markham, A, 2012. Mine site stream diversions - A balance of competing objectives, in Proceedings Life-of-Mine 2012 , pp 215-218 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By Steve Kral

When discussing stock market investments, a company's performance is important. But so is the financial community's perception of that performance. To be sure, a good product or service, coupled with sound manage¬ment, remains important but is no longer enough. How stock analysts view a company's performance has become equally important. A major task of a mining company's investor relations officer, then, is to build and maintain a positive perception of the company to mining analysts throughout the world. That's a tough assignment in any market. The subject here, though, is gold. And, with its weakened price, gold companies must work harder to convince analysts their company is still a good investment. The analyst, on the other hand, must see through the corporate hype and decide whether it's worth recommending to clients as an investment. No simple task, either. Annual reports, 10-K forms, and quarterly reports only tell part of the mining company's story. Site visits, complete with discussions (sometimes interrogations) with a mine's principals, oftentimes tell an analyst more about a company's investment potential than the annual or quarterly report. So it was that three of the nation's major gold companies arranged a three-day tour of their gold operations in Nevada for a group of 22 analysts and a pair of mining industry scribes. The analysts represented investment houses the US, Canada, and England. The host companies and mines visited included FMC Gold's Paradise Peak mine, Amax Gold's Sleeper and Wind Mountain mines, and Battle Mountain Gold's Surprise and Fortitude mines.

Jan 1, 1989

By A. Mull, J. Weyer, J. Brune

"The “Reiche Zeche” mine in Freiberg, Germany, a 600-year-old lead-zinc-silver mine with extensive open mine workings, experiences severe ventilation losses due to leakage. Much air leaks into abandoned workings, decreasing the airflow available to active working areas. Usually, this leakage occurs in remote areas that lack transportation infrastructure like roadways or rail, making it difficult to haul construction materials to the sites to erect passive ventilation controls such as stoppings, regulators and seals. Transportation distances make it impractical to hand carry traditional construction materials, such as bricks and concrete. Alternative materials, such as brattice, foaming polymers, concrete canvas, and some innovative ventilation control designs have been investigated for this purpose. The suitability of the materials investigated depends on many factors including the pressure it can withstand, the ease of transportation, and workability. Impacts of mine water must be considered, as the Reiche Zeche is below drainage and experiences significant inflow of water. Researchers must consider the effects water inundation as well as how the stopping construction material reacts to being exposed to acidic mine water. INTRODUCTION Problem Statement Mining in the area around Freiberg, Germany began in the 12th century. The mine is used for research, mining engineering education, tourism and air conditioning for a local hospital. The first records of mining in the Reiche Zeche are from around 1384. Due to the strength and competency of the host rock, many of the oldest workings still stand and remain open today, although they may not be accessible. Reiche Zeche also connects to several other, closed mines in the area that are largely unmapped. This allows air to leak into neighboring mines, reducing the air available to ventilate to the working areas of Reiche Zeche. In order to improve ventilation efficiency, it is necessary to control the ventilation and reduce leakage by constructing seals, stoppings and regulators. A challenge with building traditional seals and stoppings in the Reiche Zeche is that the old workings lack transportation pathways or rails. Also, the lack of compressed air, water or electricity makes it difficult to operate power tools and drills. This means that construction materials must be hand carried – some over distances of several kilometers. Figure 1 shows a typical drift in the Reiche Zeche. Researchers investigated using lighter, more easily transportable materials including concrete canvas, expanding polyurethane and polyurea foams, and brattice. The applicability and utility of these materials depends on a variety of factors including the ventilation air pressure, chemical resistance to acidic and mineral-laden mine waters, ease of transport, and ease of construction. Stoppings and seals must be substantially constructed so that they remain tight and do not require maintenance. It is also important to consider the toxicity of the construction materials in case of a mine fire."

Jan 1, 2016

The following data are put together to assist those who are responsible for ordering stores for mines and works. When making out a list of mine stores for a new plant, one can hardly be expected to remember everything, still it is all the more important that articles should not be forgotten, should the mine be situated in an out of the way place, where the manager has to look several weeks ahead. A man who has been accustomed to buy stores on a small scale, from local merchants, where he could pick out personally what he wanted, may suddenly find himself in a place where he has to order wholesale quantities or make out store lists to send contractors for quotations. As it is of course cheaper to purchase stores by the hundredweight, coil, barrel, etc as the case may be, in which they are made up, than to break such a parcel, the way in which the materials are placed on the market is mentioned, so that those who don't know may take full advantage of wholesale terms. The most frequent sizes and brands employed in connection with Australian mining are also mentioned. It would be useless to enumerate all sizes made by the trade, as many would be of no value for our purpose; still I have put down what will serve as a reminder to the manager to mention what size he requires when giving an order, such as the diameter of dynamite cartridges a slight neglect of this sort has often caused serious delay. By mentioning certain brands I do not wish to recommend them in preference to others inadvertently omitted they are simply mentioned as some of those frequently met with.

By W. D. Haley

The report of the Forestry Committee, presented to the recent Imperial Conference at London, is discouraging in its view of the future of timber resources and supplies. From a review of the forestry situation throughout the world, there is every likelihood that, thirty years from this, a shortage of the soft-woods will be severely felt. In the United States, only about one-third of the present forest area contains virgin timber. This will be cleared at the rate of five and a half million acres a year, so that in twenty-five years it will be about all gone. Canada has only about 27 per cent of her original forests left, and her virgin soft-wood will last but another half century. At the present time, the value of her lumber products is over $300,000,000 annually. During the summers of 1909 and 1910, the Government of Nova Scotia caused an examination to be made of the forest conditions in this Province. The reconnaissance, which was under the direction of Professor B. E. Fernow, of Toronto, involved an examination of the various soils, the rate of growth of the wood, and a general survey of the forest area. The importance to the Province of conserving its forest resources was clearly shown, and a number of recommendations were made, which; however, were never acted upon.

Jan 1, 1927

By D. Runnels, Daniel Roy, Ricardo Esteban, J. Torrealba-Vargas

"An intuitive way to reduce power consumption in grinding operations is to feed the grinding circuit with finer feed by enhancing blasting and fragmentation control. The optimization of blasting with the objective of minimizing power consumption in grinding is not new.The study was based on a Canadian mine that processes a very hard ore. BBA conducted blasting/fragmentation and grinding circuit surveys in 2014. The results of the exercise were used to develop a base case model to simulate the effect of blasting in the operation on the grinding circuit. Tools for fragmentation simulations, particle size measurement and crushing/grinding simulations were used with the objective of reducing the OPEX costs including power consumption.The paper describes the steps involved in the model optimization as well as an economical evaluation of the OPEX savings.INTRODUCTIONIn 2014 BBA was retained by one of its clients to conduct a crushing and grinding survey. The objective of the survey was to update the grinding circuit model with production data and also to develop a tool to investigate opportunities for process improvement.A second phase of the study involved the development of drilling and blasting and crushing models. The models were used to diagnose the operations and to investigate opportunities for process improvement.The objective of the present study is to describe the approach and to identify potential improvements to overall mine site operating costs by better integrating mining and milling operating costs with blasting and grinding models."

Jan 1, 2016

By Walter Valery, Sarma Kanchibotla

Due to the global financial crisis, the world economy has turned upside down and most major economies in the world are facing severe recession for the past one and half year. During this period most commodity prices have tumbled by more than half from their peaks and such a sudden and severe economic downturn is not seen since the great depression. This sudden drop in commodity prices and lack of credit made many mining operations unviable and even those mines that are marginally viable at this point are operating under severe cost pressures and capital expenditure restrictions.

Jan 1, 2010

Paddington processing plant is located approximately 30 km north of Kalgoorlie on the Menzies Highway and is owned by Placer Dome Asia Pacific. First mining was from the Paddington Pit, but in subsequent years the plant has had a history of treating ores from a large number of sources, and has used several different methods to reconcile mining and mill production. Reconciliations are necessary to keep a check on the quality control of mining and grade control processÆs. There is a need to be able to identify and resolve issues that will affect the profitability of the organisation quickly. They are also used to check the quality of the resource/reserve statements, and allow the accurate and timely payment of royalties to stakeholders. During the formation of the Kalgoorlie West operations when Delta Gold Limited and Goldfields Limited merged in 2001, the complexity of reconciliations increased dramatically. The expansion of the scope of reconciliations to include two mills, four underground mines and seven open pits, and ore from one deposit to both mills meant that a revised strategy was essential. A variety of issues have arisen over the years with discrepancies occurring when reconciling both tonnes and grade. There are many ways to approach reconciliations, and in recent times these philosophies have been widely debated on site. A consistent and logical approach that takes into account many different sources of ore, as well as different methods of delivery to the Run of Mine stockpiles is therefore necessary. This would standardise the different approaches taken by the various operations that combined to form Kalgoorlie west. The new method reconciles mill production back to the individual ore sources, and produces reconciled-mined tonnes and grade based on the mill throughput and the change in stockpiles. There will generally be a small discrepancy between the claimed mined tonnes produced (and grades) and the mill production. This needs to be highlighted to the operations concerned if it considered unacceptably large. Paddington mill over the last few years has had up to ten sources of ore each year, and up to 15 different stockpiles being processed during each month from those various pits. This combined with the need for a blended oxide/fresh feed, whilst striving to deliver a consistent (grade and hardness) product to the mill, has meant that reconciliations have been very difficult.

Jan 1, 2003

By M. J. A. Ruszala

Aggregates production is a huge global industry which uses an enormous amount of energy and produces a massive amount of unsalable fines. Reducing the amount of energy used per tonne of product and/or the amount of fines produced, would make a quarry more efficient. This reduction would make the quarry more environmentally friendly and profitable. This research looks at modelling Mountsorrel Quarry, a granite quarry in the United Kingdom (UK), using JKSimMet and Split-Desktop software packages in conjunction with the European Union (EU) project, EE-Quarry. Samples submitted to drop weight tests confirmed Mountsorrel Quarry granite as an extremely hard granite. Rock fracture data (t10) and energy of comminution (ECS) data were obtained from analysing the results. Split-Desktop image analysis software was utilized to determine the particle size distribution (PSD) of the primary crusher feed, as it contains particles too large to screen manually. It was also found that <1% of the feed is fines, which at Mountsorrel Quarry are classed as particles smaller than 5 mm, and that no particles were larger than 3,810 mm. JKSimMet was used to create a flowsheet of Mountsorrel Quarry. The crusher product PSDs were simulated and found to have strong correlations with experimental data, calculated by screening samples from conveyor belts, especially in the fines region, with a mean difference of 1%. The simulated primary crusher product PSD showed that it contains ~6% fines. A simulation over the entire quarry showed the product to be within the size range produced at Mountsorrel Quarry, and with a simulated fines content of 13%. When the CSS on the primary crusher was altered from 165.1 mm (the operating size on site) to 100.0 mm, it increased the overall percentage of fines produced by 3%, increased the power draw by 140.6 kW, but reduced the overall plant production percentage of fines by 2%. Two blasts were analysed on adjacent rock faces. They had identical blast designs, but the order of deck detonation varied; the first blast detonated the bottom deck before the top and vice versa in the second blast. For each blast, measurements of the feed PSD to the primary crusher, the number of particles that required secondary breakage on the quarry floor, acoustic levels and vibration readings were measured. No significant difference was identified between the two blasts in any of the parameters measured. In conclusion, a working model of Mountsorrel Quarry has been made in JKSimMet that has been validated against data from site and Split-Desktop has been used to simulate the primary crusher feed PSD, something that was previously unknown. The effect of reversing the order of deck detonation in a two deck blast was also analysed but with no significant difference between the two blasts found.

Aug 1, 2013

By M. J. Blattman

The problem of measuring the amount of rock removed during a given time interval is faced by most milling operations. Many methods have been developed with varying degrees of success, dependent upon the mining method and the availability of usable data. The Rosebud Mine has been in production for nearly two years, employing several techniques to estimate monthly production from underground production stopes. The use of three-dimensional solids generated from survey data has greatly improved the reliability and confidence of monthly production reports. The authors will summarize the methodology currently being utilized at Rosebud.

Jan 1, 1999

Underground excavations are subjected to complex stress changes caused by nearby mining, but may also be affected by repeated dynamic loading from blasting and seismic events. In some cases, the combined, cumulative effects can lead to unforeseen damage, displacement and instability. Simulating dynamic loading of an underground excavation is a very complex task. The state of rock mass stress, damage and deformation must first be simulated sufficiently requiring small-scale structures to be explicitly modelled. Supporting elements must be represented with high similitude and then the dynamic event must be applied to the system in the case of blasts, or evolve as a consequence of rock mass instability for seismic events. A special case is for the effect of pit blasting on underground excavations - discontinuous rock phenomena at scales from mine, to bench, to pillar, to tunnel need to be captured and this represents one of the most computationally intensive tasks in mine simulation. Recent advances in computer power allow these tasks to be completed at a mine scale, incorporating discontinuities and geological detail matching the best practice for static Finite Element analyses. The results are a worthwhile contribution to mine decision-making, but require careful interpretation and thoughtful inputs - even more so than quasi-static analysis - as the cumulative effects of unfavourable modeling practices are greater. Some learnings from experiences with mine scale, discontinuum dynamic simulation are summarised, including a discussion of considerations of scale and similitude for this type of analysis.

Nov 25, 2010

By T. W. White

One of the objectives of today&apos;s mine superintendent is to increase his equipment availability. To this end we have seen improved scheduling procedures, preventive maintenance programs and extensive drive training and operating procedures. However, until recently, one area that has changed little in the past twenty years is the method of refueling and servicing mine equipment. In looking at mines across the country continually one encounters the hazardous oil soaked ground, the hand held fuel nozzle and the maze of hoses of the "traditional" fuel stop. By adapting technology developed in the construction and aircraft industry, current fueling and servicing practices can be easily improved. The result will be less nonproductive time, less downtime from engine failures and increased security from major refueling fires. The time saved almost amounts to having another truck in the fleet! One feature of the improved servicing practice is the implementation of high flow fueling. For trucks now on the market, a flow rate between 120 and 150 gam is feasible, about 90 gam greater than current practice. This flow rate could be increased even further as larger trucks come into use. A second idea borrowed from the aircraft industry is the use of positive lock type connection nozzles that automatically shut off when flow stops. These may be used for fuel, water, oil and hydraulic systems to eliminate spillage and assure that clean fuel, oils, and water are delivered to the vehicles. The reduction of fuel spillage lessens the threat of major fires resulting: in equipment damage and loss. Eliminating fire hazards will become even more important as the turbine engine with its lighter, more volatile fuels come into common use.

Jan 1, 1972

By H Arvidson, C Morley

Reconciliation has become very topical over the last ten years but how do we distinguish what is good practice, and even more importantly, show how it adds value? Reconciliation at Anglo American has received support from the very top of the company and this has enabled success in the design and implementation of a range of processes, reporting activities and actions. Focus has been on full Mine Value Chain Reconciliation (MVCR) from Resource to Product and on proactive cross-functional engagement. A standardised set of reconciliation definitions and relationships are used at all mines across the company to diagnose planning and performance issues. Results are formally presented in an efficient dashboard format, accompanied by a concise narrative to communicate what has been learned and what is being done to correct, improve or change practices. Importantly, effort has also been made to sustain MVCR by embedding good practice and quantifying the benefit of reconciliation explicitly via linking results to value.This paper sets out the lessons learned from the past two-years’ journey, highlighting areas where good practice has been defined and achieved. A ranking for quantifying reconciliation confidence over time is presented as a means of putting results into context and continuously improving the reconciliation process. Finally, a solution to define the value that can be derived from reconciliation is described, detailing how cross-functional personnel meet monthly to review results and implement actions that are tracked in terms of value creation.CITATION:Morley, C and Arvidson, H, 2017. Mine value chain reconciliation – demonstrating value through best practice, in Proceedings Tenth International Mining Geology Conference 2017, pp 103–116 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By Howard L. Hartman

If I told you tonight at the outset that my prognastications for the future of mine ventilation were imparted to me by a palm reader or inspired by a vision, you&apos;d dismiss what I had to say before I said it! If, on the other hand, I told you that my forecasts were the result of an elaborate computer model, derived from a complex algorithm, which in turn relied on finite element analysis -- and the entire projection confirmed by on-site experiments with a turbo hybrid-flow mine fan -- you&apos;d sit up in anticipation and hang on my every word!! All of which places me in a terrible dilemma, because my predictions really lie somewhere in between. My intent is to talk to you out of my background of forty years in mine ventilation, looking ahead to conditions that I expect to prevail in the next fifteen years. You may be curious why I picked an unlikely time span of 55 years for my overview, and my response is that it bridges a career lifetime. "The last forty", of course, corresponds with the period of my professional employment since graduating with a B.S. and M.S. here at Penn State. "The next fifteen" bridges the period I expect (the Lord willing) to remain professionally active -- and coincidently brings us into the beginning of the 21st century. (I must confess to stacking the deck a bit: Since it&apos;s infinitely harder to look ahead than to look behind, I purposely minimized the forecast period and maximized the history! Besides, "forty" and "fifteen" have a nice phonetic ring, perfect 20/20 vision sums to "forty", etc., etc.). With these disclaimers, I&apos;ll invite you to join me now in a fast 55-year overview of mine ventilation, of necessity limited to a broad-brush treatment of the subject. (After all, this is an after-dinner talk, not a marathon!) In each- segment, I&apos;ve selected the seven topics that seem to me of paramount importance: in the first part, seven accomplishments in retrospect, and in the last, seven expectations for the future. (The number "seven" needn&apos;t confound you, either: In the bible, it signifies "wholeness" or "completeness".))

Jan 1, 1987

By A. R. Bell

Rio Algom Limited are currently undergoing a major expansion of their mining operations in the Elliot Lake area. To date this has involved the increase of output at the Quirke Mine from 4080 to 6350 tonnes per mill day (4500 to 7000 tons), the rehabilitation of the Panel Mine to produce at the rate of 2990 tonnes per mill day (3300 tons) by 1980, and the rehabilitation of the Stanleigh Mine to produce 4540 tonnes per mill day (5000 tons) by 1984. In addition, the planning for the rehabilitation of the Milliken Mine to produce 4990 tonnes per mill day (5500 tons) is now underway. This major expansion is taking place at a time of increasing awareness of occupational health matters and has involved very high capital expenditures and detailed planning related to the ventilation system to endeavour the provision of an acceptable environment. The paper discusses the ventilation systems, established and proposed, and relates them to historical and current data on mine air contaminants.

Jan 1, 1980

By Lennart Mukka

The Kiruna Mine in Sweden currently has three ventilation systems. The first two (a new and old system) serve the production areas. The third system is used for the facilities on the former main haulage level 775. That area includes offices and workshops for load haul dumpers (LHD) and drill rigs. The third ventilation system also covers the crushing and haulage on level 1045. At the present time, the total airflow for the mine is 1,600 m3/sec(3.4 million cfm). The current system serves the levels above the 775 level. The new one is for the levels between 775 and 1,085 m (2,540 and 3,560 ft), which are needed for the new ore body. When all of the production is below level 775, the old ventilation system will be closed down.

Jan 1, 2002