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By John Hoffert, Darren Colwell, Greg Tucker, Jeremy Kinch, Greg Rasmussen

"The Kemess Mine, a major producer of gold and copper, is located in north-central British Columbia. Kemess was brought into production in May 1998 by Royal Oak Mines. On February 11, 2000 Northgate Exploration Limited acquired Kemess Mine from receivership. Since acquisition in 2000 Kemess has seen many accomplishments, including the reduction of costs by 40%.One of the largest site capital costs was the construction of the tailings storage facility dam, which when finished will be one of the largest earth filled dam structures of its type. The existing construction design by AMEC called for a kilometer wide rock dam to be built from the 1350 M elevation to the 1504 M elevation at a 5.5:1 slope by hauling over 30 million tonnes of non-acid generating waste rock 7-kilometers from the open pit to the tailings dam, which was highly expensive.Kemess realized an opportunity for cost reduction was possible if the dam could be built from suitable quality tailings sand; however the sand did not meet the neutralizing potential ratio specifications. It was determined that cycloning combined with flotation to reduce pyrite concentration in the sand would produce a non-acid generating product for dam construction. The sand plant design challenges were to remove the sulphides from the tailings to obtain an NPR greater than 2:1 and provide a consistent sand product for the construction with a fines content of less than 15% passing 200 mesh. After a 2-year testing design and construction period, the sand plant was successfully started at the end 2002 resulting in higher than expected sand quality and production rates.This paper describes the plant design phase, commissioning, and operation of the tailings sand plant for construction of the tailing storage facility dam to enable us to meet all the engineering and regulatory requirements. The many challenges faced were successfully met using several innovative designs. The operational, economic, and environmental benefits are detailed."

Jan 1, 2004

By Verya Nasri, Heather M. Ivory, Kevin Clarke, Eric Cole

Development of the New York City Water Supply System The New York City water supply system serves a population of almost nine million, including residents in neighboring counties. Peak day demands on the system are currently running at about 70 m3/sec (about 1,600 mgd), which is significantly lower than in the 1990s. This trend of reducing demands over the past 25 years, which has been experienced in other major urban centers in the US, is mainly the result of conservation measures and increased cost consciousness on the part of water users. In the long term, demands are expected to once again follow an increasing trend with population growth, so that by the end of the planning horizon of these studies, the year2045, the peak day demand is expected to increase to about 85 m3/sec (2,000 mgd).The system is served largely by surface water sources, regulated by a system of 19reservoirs and three controlled lakes, which are connected to the City by a series of aqueducts, the longest of which is about 87 km (54 miles). The total storage in the sys-tem amounts to about 560 billion gallons, providing a system firm yield of about1300 mgd. The Delaware system provides about 50% of the City’s water, the Catskill about 40%, with the remaining 10% provided by the Croton. The system as a whole, which is shown on Figure 1, has been built up over the past 150 years, and is truly a marvel of engineering. The Catskill and Delaware aqueducts both discharge into Kensico Reservoir, which is a daily balancing reservoir located in Westchester County about 24 km(15 miles) north of the New York City line. The two aqueducts extend south for a further 14 miles to combine again at Hillview Reservoir in the Bronx, which provides hourly balancing storage for New York City system. The Croton aqueduct runs nearby as shown on Figure 2, but does not connect into the two reservoirs. From Hillview Reservoir the water is supplied to the city via three main distribution tunnels, known as City Tunnels 1, 2, and 3. City Tunnel No.1 was developed in the 1920s as part of the Catskill system. City Tunnel No. 2 followed in the 1960s as part of the Delaware system. City Tunnel No. 3 (CT3) is partly under construction and partly in operation, and is being implemented to permit the other distribution tunnels to be taken out of operation for the first time for inspection and maintenance. Presently CT3 is supplied with water from Hillview Reservoir via a large underground valve chamber, the Van

Jan 1, 2007

By Robert J. F. Goodfellow, William A. T. Meakin, Kevin Clarke, Eric Cole

INTRODUCTION New York City Water Supply—Background and History Since the 1840s New York City has been developing the largest, and perhaps, the best urban water supply and distribution system in the world in terms of quality and reliability. One of the engineering marvels of the modern world, the New York City water supply and distribution system serves a population of almost nine million, including residents in nearby Westchester, Putnam, Ulster, and Orange Counties of New York State. The average daily supplies presently are running at almost 60 m3/sec(about 1,350 million gallons per day). The watershed for the New York City water supply system, under the jurisdiction of the New York City Department of Environmental Protection (NYCDEP), consists of19 reservoirs and three controlled lakes, and covers an area of approximately5,000 square kilometers (about 2,000 square miles) north of New York City. The watershed total available storage capacity is about two billion cubic meters (560 billion gallons) and is divided into three reservoir systems: the Catskill and Delaware watersheds located West of the Hudson River; and the Croton watershed, located east of the Hudson River, see Figure 1. The first element of the system, the Croton Aqueduct, started operations in 1842.Through several updates and expansions, the present-day Croton system was in place by 1911, providing a potential maximum supply of about 15 m3/s (about 340 mgd). The system includes ten reservoirs and three controlled lakes. In the late 1800s, with the tremendous growth of the City, New York City water engineers began to look for additional sources. Between 1907 and 1929, the City acquired water rights and constructed a new 148 km (92 miles) Catskill aqueduct to convey water from the Ashokan Reservoir to the City. The Catskill system also included the construction of the Kensico and Hillview Reservoirs just north of the City,

Jan 1, 2005

By Knevitt L. T

PART 1Details of Kiewa Scheme.Introduction.Topography.Preliminary Investigations.Geology.Description of Project.Details of Main Works.Main Transmission of Power.Construction Facilities.PART 2Underground Works.Summary of Projected Works.Administration.Labour.Surveying.Safety and Accident Prevention.Medical Attention and First Aid.PART 3No. 4 Head Race Tunnel.Summary.Geology.

Jan 1, 1950

By M. J. Nicol

The kinetics of the dissolution of colloidal silver in aerated cyanide solutions has been investigated with the aim of developing a relatively rapid and convenient method for monitoring the ?leaching power? of solutions typically used in the cyanidation process. Experimental results obtained are consistent with an electro-chemical model, in which the mixed potential is set up in the active region of the polarization curve for the anodic dissolution of silver, giving rise to a rate of dissolution which is controlled by the rate of mass transport of either cyanide or oxygen to the surface of the silver. The rate of dissolution of colloidal silver was found to respond to variations in the reactant concentrations in a similar manner to gold (and silver) in a typical free-milling ore. The use of this technique for the monitoring and control of the cyanide leach process is discussed.

Jan 1, 1998

By Kiran B. Chaudhuri

The Kivcet process is technologically the most advanced of the new lead smelting processes which have been developed over the past decade construction of the first commercial scale Kivcet lead smelter which has been designed by KHD Humboldt Wedag for Sociedad Complejo Metalurgico de Karachipampa is at present nearing completion in Bolivia. Some of the measures taken to minimise emission of harmful elements as well as methods employed to minimise energy consumption in the design of the smelter, are presented. Results of recent testwork which have added to the flexibility of the process are summarised.

Jan 1, 1982

By Christos Roumpos, Philip‑Mark Spanidis, Francis Pavloudakis

Coal mining operations are large-scale, long-term frameworks of high complexity. Mining organizations accumulate, develop, and leverage knowledge from diverse scientific and technological fields as a result of these operations. Both practical experience and existing literature indicate that knowledge management (KM) methods within the mining industry primarily target solving immediate technical challenges and operational requirements. However, they are not commonly regarded as strategic tools to enhance the performance and competitiveness of mining companies. Empirical evidence from the Greek mining industry suggests that the management of available knowledge is intricate, less effective, and dysfunctional. This paper presents a methodology based on the principles of quantitative research (QNR), collaboratively conducted with a group of mining experts, to assess the KM landscape in the Greek mining industry. The methodology involves a structured data collection framework using questionnaires, subsequent statistical analysis, a discussion on critical methodological aspects, and an interpretation of results focusing on key aspects useful for planners and designers of KM systems in the mining industry. Finally, the paper concludes by summarizing the methodology’s outcomes and proposing further perspectives for research.

Mar 16, 2024

By L Spencer, H Zwingmann, I Graham, D Cendon, B Kelly, D Burkett, F Lau, P Lennox

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Kulumadau deposit represents an intermediate-sulfidation epithermal gold deposit (3.8 Mt at 2.3 g/t, Ag:Au = 1). Mineralisation is primarily confined to hydrothermal breccias within pre-existing fault zones, where it is disseminated throughout a hydrothermal matrix comprising chlorite-quartz-adularia-illite-I/S clays-calcite-pyrite. The host sequence represents numerous mid-Miocene pyroclastic flow eruptions within a tectonically active emergent shallow marine to subaerial depositional setting. Subsequent growth faulting was responsible for debris avalanches, which were subsequently cut by reverse faults. Faults were exploited by hydrothermal fluids, with the heightened porosity at the juncture between faults and debris material facilitating boiling of the ore constituents. Fluid inclusion studies suggest that fluid mixing between meteoric fluids and magmatic fluids, accompanied by boiling, were the primary mechanisms for gold deposition. The occurrence of anhydrite/gypsum as late-stage veins and their sulfur and oxygen isotopic values indicate post-mineralisation mixing of sea water with hydrothermal fluids.CITATION:Burkett, D, Graham, I, Spencer, L, Lennox, P, Cohen, D, Zwingmann, H, Lau, F, Kelly, B and Cendon, D, 2015. The Kulumadau epithermal breccia-hosted gold deposit, Woodlark Island, Papua New Guinea, in Proceedings PACRIM 2015 Congress, pp 205–212 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By John Kazakoff, Andrew Mortimore

"Production at the remote Kumtor Gold Mine in Kyrgyzstan commenced on schedule in December 1996.The ore mined during the first few months of 1997 from the upper benches of the pit did not produce the results predicted by the feasibility study. Low metallurgical recoveries experienced at the time were cause for great concern.It soon became clear the recovery difficulties centred around the preg robbing nature of the ore.Procedures were developed to selectively stockpile highly carbonaceous low recovery ore types. Testing methods were developed in the mill to quante the preg robbing activity of the ore. Preg robbing masking agents were added to the process to reduce the preg robbing activity of the ore.The importance of coconut carbon activity relative to the preg robbing activity of the ore was realized. Every aspect of the performance of coconut carbon in circuit was evaluated and optimized to improve carbon activity.Mineralogical analyses were completed defining the deportment of gold in ore and process tailingsBy year end the recovery difficulties had been overcome and plant design production had been achieved. Process improvements continue through 1998."

Jan 1, 1999

By Constance Holmes

President Lien presented Mrs. Holmes with the first of speaker appreciation gifts presented by his firm Amax Coal West, Inc. These were books by Rand-McNally entitled The Executive Golfer Guide. Following the coffee break, Clark Moseley presented the first annual Institute Safety Achievement Awards for the safest mines in the eight member state region. The awards were based on: 1. Total man-hours 2. Total number of lost time accidents 3. Incidence rate 4. Number of S&S violations 5. Description of safety program 6. Safety awards received 7. Health and safety training efforts 8. Safety Policies 9. Does the operation take employee suggestions and implement them? 10. Letter(s) of commendation from agencies individuals The awards were judged by the senior/graduate level class of Mine Safety & Health at the Colorado School of Mines under the supervision of professor Edward Hollop. The two handsome traveling trophies were awarded to and accepted by: Surface: Big Sky Mine. Colstrip, Montana Gordon Brannon, Manager of Safety Underground: Skyline Mine, Scofield, Utah Dave Hales. Safety Supervisor and Doug Johnson, General Production [ ]

Jan 1, 1998

By H. -Peter Sattler

The laser sorting technique for replacing the handpicking of the non-ferrous metal scrap from auto shredders was first introduced 1990, The process is based on the use of atomic emission spectroscopy induced by lasers to identify the scrap particles and sort them with adequate systems into main fractions of Al-, Zn-and Cu-alloys, stainless steel and lead, In the meantime the handling technique for the scrap, i.e. the singling and sorting technique as well as the analytical detector were further developed for more efficiency and higher reliability, i,e. less maintenance, minor sorting errors etc. These developments were mainly based, on and initiated by operational experiences from the startup phase of a first production plant. Part of the on going research work was the development of an ,aluminium detector which makes it the first time possible to sort mixed aluminium scrap automatically into specific alloy fractions.

Jan 1, 1995

By Hans von Michaelis

The current exploration boom in Central and South America shows no sign of abating and, if anything, is growing. This is despite an inevitable cooling in the recent frenzied buying of resource stocks on the Canadian exchanges which have funded much of the Latin American exploration. Several factors appear to be driving the boom. Firstly, the resource potentials in this vast under-explored regions are nothing short of phenomenal. Secondly, after decades of stifling nationalization and restrictions that stood in the way of foreign investment, especially in mining, emerging nations the world over now suddenly find themselves competing with each other to be the most attractive.

Jan 1, 1995

By NORMA D. MACFADDEN

WHILE the library work of the Woman's Auxiliary to the A. I. M. E. was founded three years after the formation of the Auxiliary, its present policy of establishing permanent libraries in mining camps throughout the United States dates only from 1924. Since then sixteen libraries have been established and thousands of books have found their way to homes of far-away miners, bringing pleasure and knowledge to a multitude of Americans and future citizens. Library work was initiated under the presidency of Mrs. H. W. Hardinge in 1922 and firmly established with her aid as one of the main activities of the Auxiliary. The first chairman served but a short time and Mrs. A. O. Ihlseng then took over the work of chairman of the Library Committee. To place the surplus books of Auxiliary members and their friends in use in mining camps was the immediate work of the committee. This was accomplished by placing a traveling library in the Bureau of Mines' cars and also by sending books for distribution to section chair- men in our larger mining camps.

Jan 1, 1929

By Yeonuk Choi, Gus Van Weert

"In regular CIL circuits, activated carbon is used for two purposes: avoiding solid/liquid separation after cyanide leaching, and minimizing gold losses in the tails. The carbon distribution and gold profiles in the successive CIL stages are operating variables, not objectives. When the CIL feed contains a preg robbing constituent however, such as native carbon, there will be competition for gold cyanide and this conflicts with minimizing of losses of gold to CIL tails. This paper examines some of the limitations of activated carbon in CIL circuits handling preg robbing Carlin Trend ores.INTRODUCTION Carbon-In-Leach (CIL) has been a great success treating regular gold ores, but the technology is still challenged by preg robbing feedstocks. Little information is available in the gold milling literature on CIL gold extraction from “free” milling gold ores which are preg robbing, or on autoclave discharge (POX’ed) slurries of double refractory ores. Neither feedstock is readily available for experimentation. No literature reference could be found describing deliberate modifications to CIL operations or CIL circuits due to the presence of two types of carbon: “native” and activated. There is some literature on the gold cyanide adsorption activity of native carbons (Schmitz, Duyvesteyn, Johnson, Enloe & McMullen, 2001). Various tests have been devised to measure this activity, commensurate with CIP and CIL practices (Tretbar, Arehart & Graves). In this paper, the term “native” carbon indicates (severely) preg robbing carbonaceous materials found in gold ores. There is considerable literature on the gold cyanide adsorption activity of man-made “activated carbons”. Various tests have been devised to measure this activity, commensurate with CIP and CIL practices. These tests are comparative, i.e. results relate to a standard carbon and depend on the test methodology and carbon history. The test results are equilibrium oriented, hence of limited value to CIL circuit designers or plant operators handling preg robbing solids; in CIL circuits most carbons are not loaded to capacity. Information on gold cyanide adsorption and desorption kinetics might be more relevant and that is one subject explored in this paper."

Jan 1, 2012

By A. R. Laplante

Recent developments in gold metallurgy are used to illustrate how the interface between gravity recovery and hydrometallurgy has evolved in recent years. Of particular interest is the use of gravity recovery to produce high-grade concentrates that can be subjected to intensive cyanidation. It is expected that a growing proportion of gold production, possibly close to 50% in certain countries, will follow this route. Other examples of the interaction between gravity recovery and cyanidation are also provided. Implications for new and renewed research directions are discussed.

Jan 1, 2003

By D. Knuutila, G. Goyette, James A. Finch, G. Bartolacci, A. Fortin, Chi Ho Lau, A. Lockhart

"In a COREM-McGill collaborative research and development project, gas dispersion parameters and froth properties were manipulated in a copper flotation plant to study interactions between the collection and the cleaning zones. In this paper, specific work on developing some relationships between operating conditions and froth stability in a rougher column flotation cell of 125 m3 is reported. Froth stability, measured by image analysis, was related to the following process conditions for specific flotation machines in an industrial case study: Gas flow rate, collector dosage, pH, frother type and dosage. Across the range examined, froth stability was improved through a decrease in gas flow rate and/or increasing frother dosage. Metallurgical results (grade and recovery) showed that both gold and copper were dependent on froth stability.INTRODUCTIONMcGill and COREM have over the past two years collaborated in a research and development project to merge gas dispersion parameters, frother analysis (McGill technology), and froth properties (COREM’s imaging system) to study the interactions between the collection zone (pulp) and the cleaning zone (froth). The main goal is to increase knowledge of flotation cell hydrodynamics since it is known to govern the metallurgical performance of the flotation process (Power et al., 2000). In this paper, specific work on developing some relationships between operating conditions and froth stability in a copper flotation circuit is reported.The objective of this work is to study gas dispersion in a large volume flotation column (hydrodynamics) and to measure its impact on the froth. By froth imaging, it is possible to diagnose operational problems on the basis of froth characteristics (Bartolacci et al., 2005a) and consequently, to propose ways of improving process performance by froth analysis (Bartolacci et al., 2005b).Another approach to froth characterization is investigated in this paper. In the same flotation column, a froth stability apparatus (column) was included (Triffet and Cillers, 2004). The mechanical froth stability apparatus is used to link “hard” froth characteristic measurements to “soft” froth characteristic measurements (those obtained by imaging)."

Jan 1, 2008

The paper deals with the importance of design and of codes of practice in ensuring safe working conditions in mines. The design principles involved in the design process are dealt with, and the importance of a logical design process is emphasized. The links between the requirements for developing a code of practice, embodied in the existing guidelines for the preparation of such a code, and the design principles and process are considered in some detail. Finally, suggestions are included, which may provide improvements to the code and hence, ultimately, lead to further improvement in safe working conditions.

Jan 1, 2004

By I. A. Kunasz

This paper is not intended to review and re-state general information on lithium, but rather to analyze the paradigm that has caused such a rapid rise in lithium production and the development of new lithium producing centers. Details on pegmatites, brines, concentrate and chemicals are amply covered in a number of publications ? SME?s Industrial Minerals and Rocks, Industrial Minerals, Roskill and a host of other publications. There is no question that the latest interest in lithium has been driven by the potential development of the electric car. This stimulus prompts one to recall two symposia: 1. ?Lithium Resources and Requirements be the year 2000?, organized in 1976 by the U.S.G.S. in Denver (1) and the sequel 2. ?Lithium ? Needs and Resources? at Corning, N.Y. (2).

Jan 1, 2011

This paper reviews the gold mining history and recent exploration activities on a number of beaches in the Catlins area of coastal South Otago. Past mining history and recent sampling indicate the presence of economically significant concentrations of placer gold, as well as anomalous PGM, and various heavy mineral species. A local source for this placer mineralisation is considered a strong possibility, along with a contribution from the Waiau River catchment via longshore drift. Blacksand beds in Jurassic sandstones of the Southland Synclinorium may represent this local source of mineralisation on the modern beaches. The possibility of placer mineralisation extending onto the inner continental shelf is also considered. Further exploratory work is justified, both for in situ Jurassic blacksand deposits, and to delineate mineralisation in the modern beach and inner shelf environment.

Jan 1, 1992

By Rob Thomas

Adequate load transfer is considered essential for optimum ground support and is increasingly important in weak roof and/or high stress environments. If adequate load transfer is achieved not only can this have a positive impact on the resulting roof behavior, but it may also allow the use of lower and hence more economic densities of roof support. A wide variety of post-groutable cable bolts are currently in use in the Australian coal mining industry, each of varying capacity, design, and grouting methodology. Though all of the cables are supplied with the appropriate steel specification, strength, and modulus data, the Australian coal mining industry does not have access to a comprehensive and comparative database on the corresponding load transfer performance, which is a critical problem. On the basis of the above, this paper describes the methodology and results of a laboratory pull testing program that aims to assess the impact of cable bolt design on load transfer, and specifically, the impact on the capacity and stiffness of the anchorage. As part of the testing program, 19 cables were tested including (1) plain-strand cables installed in holes drilled with 28 to 55 mm diameter drill bits and (2) bulbed and nutcaged cables installed in holes drilled with 42 to 64 mm diameter drill bits. Other parameters assessed included the significance of smooth and profiled wire, wire packing, and expanded geometry bulbs. The main results of the testing indicate that in comparison to plain-strand cables, if the cable is bulbed or nutcaged, the capacity of the anchor can increase by up to 400%, and the peak stiffness by between one and two orders of magnitude. The results also indicate that increasing hole diameter may have a positive impact on load transfer in the case of bulbed or nutcaged cables and a negative impact on plain-strand cables. No conclusive results were obtained with regard to the impact of grout strength on load transfer.

Jan 1, 2012