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By T. Eger

Load Haul Dump vehicles (LHD) are extensively used in underground mining however equipment design and operating conditions contribute to restricted operator?s visibility. The inability to clearly see people, objects or hazards around the machine has contributed to a number of accidents including fatal injuries. In order to identify vehicle design characteristics resulting in restricted and blocked sightlines visibility assessments are traditionally completed in the field. However, field methods are unable to evaluate visibility under dynamic operating conditions and are limited in their ability to provide feedback on the impact of various operator characteristics such as sitting height, for example. Results of this research show computer simulation and virtual reality can be successfully used to evaluate visibility during the operation of LHD vehicles. In order to benefit from virtual reality applications the work environment, LHD vehicle and human posture need to be represented as accurately as possible. A computer simulation program with ergonomic ana lysis features, Classic JACK 3.1, was successfully used. Threedimensional CAD models of LHD vehicles were developed from manufacturer specifications and pictur es taken from LHD vehicles currently in use. The LHD models were imported into the JACK environment, a digital human was positioned in the cab of the LHD vehicle and the vehicle and human where driven over a typical mine route. Real-time feedback in the JACK program was used to identify what the operator could see under different operating conditions. Machine characteristics and operating scenarios resulting in impaired visibility were successfully identified with this method. The JACK program can also provide real-time feedback on the human?s joint forces and torques, strength requirements, postural comfort, and metabolic energy expenditure. As a result, this method could be used to successfully evaluate musculoskeletal injury risk factors along with system design recommendations to improve workplace safety and productivity in any setting. The LHD VRML files imported into JACK have also been combined with environment files into other VR software packages (e.g. Maverik) to view in a VRL facility, managed by MIRARCO at Laurentian University. The VR models using these packages can be viewed in stereo to provide better appreciation of spatial visibility issues.

May 1, 2003

Unplanned open stope hanging wall dilution is a significant cost for many open stope mining operations. Significant advances in empirical and analytical approaches for estimating stope dilution have been made, however, many important factors are still either ignored or assessed in purely subjective terms. There are many hard to quantify factors that simultaneously influence opening stability and dilution. This creates a significant difficulty for determining the influence of a single variable, such as exposure time, on opening stability. Open stope exposure time has been found to be one of the important factors that influences overall stope stability and dilution. A study is currently being conducted to quantify many of the factors influencing open stope dilution. The assessment of a large comprehensive case history database of Hudson Bay Mining and Smelting Co. Ltd. (HBMS) operations forms the basis of this study. This paper presents the findings of a study on the influence of stope exposure time on open stope dilution. The study is based on applying existing empirical stope dilution prediction methods to the extensive HBMS database. Minimising stope mucking time has been recognised as a method to significantly reduce stope dilution. Factors which influence hanging wall dilution, such as drill and blasting methods as well as undercutting the hanging wall, have been applied to reduce the scatter in the database. Empirical design techniques based on rock classification attempt to relate opening stability to ?stand-up time?, however, these approaches have not frequently been applied to the mining industry. Data from a ?stand-up time? graph have been interpreted in terms of an equivalent average depth of hanging wall slough and compared to the HBMS database findings. To add to the existing HBMS database, several stope case histories have been taken from Geco mine. These cases include data from very large open stopes with long exposure times. Data from all three sources suggest that hanging wall slough increases between .14 and 0.3 metres per month for a rock mass Q? value between about 4 and 13.

May 1, 2003

By Bryn Harris

Answer to the question is given as 42! Asked the wrong question So got the wrong answer How does this apply to the mining industry? And particularly to this session on Water? Water is just one aspect of mining/minerals/metals Should not be looked at in isolation Need to adopt a ?holistic? approach

May 1, 2013

Agenda ? Introduction ? Inmet?s Operations and Closed Properties ? Inmet?s SECA Philosophy ? Inmet?s SECA Framework ? The Business Case for TSM ? Inmet?s TSM Reporting ? Inmet?s 2004 TSM Performance ? Opportunities for Improvement ? What Have We Learned From The TSM Process So Far? ? Summary Introduction ? Inmet has evolved into a strong TSM supporter ? Inmet is confident that TSM can be successfully and cost effectively implemented by smaller companies ? Inmet?s reporting on economic, environmental and social performance was raised significantly in our 2003 Annual Report ? a signal our commitment to good performance and improvement in these areas ? Our 2004 Annual Report has been further enhanced with the inclusion of our TSM performance

Apr 1, 2005

By David Penswick

Despite anecdotal evidence to the contrary, the mining industry is not in decline. Rather, the world?s largest mining companies are among the most consistently profitable companies in any industry. In many cases, profitable mining companies have been built around a few large scale, long life mines. These criteria for success ? size and long life ? have led to the current preference for deposits that can be exploited using open pit methods. However, developments in the science of block caving have resulted in this mining method achieving costs and productivities that are competitive with the largest open pits, while achieving widespread applicability. One implication of the low costs and widespread applicability of block caving is that some current open pits are possibly too deep.

May 1, 2003

By John S. Stevenson

"Although we have no uranium- producing mines as yet in British Columbia, uranium, associated with gold and cobalt, has been found in two deposits in amounts such that the combined value of the metals not only warrants the further exploration of these deposits, but also encourages the search elsewhere in the Province for other similar deposits.Where uranium-bearing veins have been found in British Columbia, the uranium mineral is the crystalline variety of uranium oxide, uraninite, rather than the massive, non-crystalline variety, pitchblende, such as found in the Great Bear Lake deposit and in other similar deposits along the southwestern margin of the Precambrian shield.The principal occurrences of uranium known so far in British Columbia are associated with bodies of granodiorite and quartz diorite along the eastern side of the Coast Range belt of batholiths. In this part of the Province, interesting amounts of uranium occur on the Gem property in the Bridge River area and on the Victoria property south of Hazelton; and smaller amounts occur on the Red Rose, Rocher Debouze, Delta, and Ohio properties, also south of Hazelton. At the Gem and the Victoria, the uranium mineral, identified as uraninite, occurs in deposits that also contain abundant cobalt-nickel sulpharsenides, and molybdenite.At these properties, the uraninite occurs as clusters of small black crystals of sub-metallic lustre that may be seen upon careful -searching of a highly radioactive specimen with a hand lens. Under the microscope, the uraninite is seen to be in the form of cubes or modifications of cubes that may occur as individual grains widely scattered throughout the gangue or may be gathered into clusters of several grains. The grain size of the uraninite is in general small. Although a few clusters of grains are up to about 10 mesh in diameter, the individual grains, whether in clusters or widely disseminated, are rarely more than 400 mesh in diameter."

Jan 1, 1950

By Ernest A. Hodgson

WHEN excavations are made, at depth, in hard brittle rock structures, as in certain mines in India, in South Africa, and in Ontario, the pressure due to overburden, together perhaps with inherent geologic strain, tends to become concentrated in the walls of some of these openings and the rock bursts, often closing the adjacent drifts and scopes and presenting a serious menace to the miners. Where the rock is much fractured and faulted, the danger is greater, since the pressures tend to shift without warning from point to point, sometimes within a few hours. Attempts have been repeatedly made to find some physical property of the rock which will change with pressure, which can be measured for rock 'in place' in the mine, and which will give an indication of the state of strain, thus warning of an approach to bursting conditions. Some of the properties tested have been the speed of propagation of elastic waves in the suspect rock, variations in temperature due to pressure changes, rate of closure of openings or shifts along fault planes, strain gauge measures, and others. Each of these has proved unsatisfactory for the purpose. The most promising method so far proposed has been the study of the very faint, sub-audible snaps (microseismims) which are produced in rocks under pressure. Such a study has been in progress at Lake Shore Mines since May, 1942. Instruments designed to pick up, amplify, and record the microseismims were perfected and a programme of observing, using the microseismic method, has been carried through with persistent diligence and at considerable expense. In 1943, experience with the method in a pillar section on the west side of the Lake Shore mine gave much promise of predicting bursts. A very heavy burst on January 29th of that year occurred in the exact section of the mine covered by the instruments, and the records indicated a measure of prediction. In response to repeated requests for information, a number of reports were given out, among others a radio talk by the writer over CJKL (Kirkland Lake), which was reported in full in the Northern News . Also, a detailed account of the occurrence was given in an illustrated paper by the writer (l).

Jan 1, 1945

By A. D. Akerman, D. D. Young, G. R. Baiden

The development and maintenance of underground roadways are increasingly important aspects of the modern mining process. With the trend toward automation and track-less mining, roadbeds capable of with standing increased wheel loading have proven necessary to maintain high vehicle speed and reduced maintenance costs. Concrete has been used successfully on some roadways in order to obtain the required characteristics. However, this solution usually involves unacceptable expense. The objective of the Road Router project was to create a drift floor profiling machine capable of cutting a smooth surface out of the existing rock floor of development drifts and ramps. This surface would provide a durable, high strength, low rolling resistance roadbed that would allow for reduced operating cycle times and lower maintenance costs of scoops and haulage trucks. The Road Router has the potential to offer an alternative to concrete with substantial cost savings.

Jan 1, 1997

By Hung-Ming Chen

This paper presents a Cloud-based system framework for providing a web-based building information model (BIM) service. Cloud computing technologies were used to develop a BIM data center, which can handle the big data of massive BIMs using multiple servers in a distributed manner. In addition, the system allows multiple users to access the BIM data center online to submit and review BIMs concurrently. In this study, the advanced technologies/tools of web development and Cloud computing were applied and incorporated to develop a prototype system, named CloudBIM. On the client side, this study applied WebGL and HTML5 in the web-based interface development to achieve the 3D display of BIMs and the dynamic interaction with viewers through browsers. Users can access the services of CloudBIM by using PCs, laptops and tablets anytime anywhere to view the 3D model via browsers, which support WebGL. On the server side, this study used Apache Hadoop, an open-sourced distributed file system based on Google?s technologies, to establish a BIM data center. The Hadoop Distributed File System (HDFS) can utilize multiple servers to provide mass storage spaces in a distributed manner. Based on the use of Apache HBase, which provides Bigtable-like structured storage for HDFS, this study proposes database schema for storing the information from massive BIMs in two bigtables, named Object table and Property table respectively. In addition, Hadoop MapReduce, a Hadoop component for the parallel processing of large data sets, is utilized for model data acquisition by parsing the IFC files of uploaded models in parallel.

Aug 1, 2013

By G. Tozsin

A six-stage sequential leaching procedure was used to assess the leachability of heavy metals from waste rock in Antamina Mine. Sequential extractions procedure is well established for fine and small (? 1g) samples. However procedures for coarse and large test samples are lacking. This study presents results of the sequential leaches tests conducted on relatively coarse and large representative samples in terms of the availability and mobility of metals. Selective chemical reagents were used to extract metals from six different fractions where metals released with each subsequent extraction are believed to be bound tighter than those released in prior steps and therefore less likely to be leached.

Aug 1, 2013

Cambior has been involved in the Guiana Shield since 1990, first in Guyana and then in Suriname starting in 1994. This paper presents the history of Omai Gold Mines Limited in Guyana, where commercial production started in 1993 after an investment of US $150 million. In 1995, the mine was expanded in order to increase the milling capacity to 21,000 tonnes per day. After ten years of production, approximately 3 million ounces of gold have been produced. Building on this experience, Cambior became involved in Suriname with the Rosebel Project. A US $95 million pre-production program started in the fourth quarter of 2002, and the mine should be in commercial production early in 2004.

May 1, 2003

By Ron Doucet

Industry today is now more than ever dependent on its assets and on the standard of maintenance. Changes in technology, environmental regulations, a continually improving focus on safety and global competitiveness has made maintenance a key activity in sustaining safe, financially viable and environmentally integral operations. Maintenance used to be looked upon as a cost centre with a sole focus of fixing equipment to attain high availability. Maintenance today affects all aspects of the business: safety, environmental integrity, energy efficiency, productivity, costs, and product quality. These new demands on the function of maintenance requires us to think vastly differently about what maintenance is all about, even to the point of contradicting old beliefs. In the following paragraphs we will examine some of the changed thinking that has evolved over the last 50 years. These new concepts will lay the foundation for the implementation of 21st century best practice maintenance.

May 1, 2003

By Craig Ford

Inmet Mining is committed to implementing the highest corporate responsibility standards in its mining operations worldwide. Inmet is 100% owner of Minera Panama, a world-class copper project that is currently in the feasibility phase in north-central Panama. Panama has limited experience with modern mining, limited mining capacity, and the project context involves significant social, environmental and political complexity. The Project area is remote with recent in-migration of latino and indigenous people, informal and small-scale mining, local subsistence populations and considerable biodiversity value, coupled with a complex jurisdictional setting. In short, it is increasingly the kind of project mining companies are taking on because the easy projects have already been developed. With such challenging conditions, anticipating and managing social risks is critical to effective project management. To this end, between August 2007 and the third quarter of 2009 Inmet seconded Monkey Forest Consulting Ltd to the project to assist Minera Panama in building and implementing an effective, early phase external relations strategy. The team was also tasked to find and develop a locally based team that could sustain success through project development and into operations. Today?s presentation was created by Inmet and Monkey Forest and describes some of the lessons learned in implementing an effective early phase process for managing social issues.

May 1, 2010

By M. P. Amsden

"Ecstall Mining is a wholly-owned subsidiary of Texas Gulf Sulphur at Timmins, Ontario. The mill tonnage is 10,000 tons per day of two different ores, a copper zinc ore and a silver lead zinc ore, producing about 2400 tons of concentrates per day. These are as a copper concentrate, a high silver zinc concentrate, a low silver zinc concentrate and a silver-lead concentrate. For flotation recovery a very fine grind is required, about 80% minus 325 mesh and the concentrates produced are 40% minus 10 microns.The thickened concentrates are pumped to the filter floor for filtering and drying. The filtering and drying section is separated from the flotation section by a wall and is controlled from a dryer control room by one operator.Two operating panels are located in this control room. One contains stop-start controls for the thickeners, filter motors and vacuum pump motors, and stop-start controls for dryer feed conveyors and dryer product conveyors to concentrate load-out bins, as well as ammeters for conveyor drive motors. Dryer throughput is regulated by Merrick Type L weightometers located on the dryer discharge conveyors and recorded on tons per hour strip charts.The second panel contains the temperature strip charts, furnace drive ammeters, scrubber and exhaust gas controls, burner controls and panel alarms for the four dryers.Filtered concentrates are dried in Nichols-Herreshoff, multiple hearth, dryers consisting of nine hearths (zinc) and seven hearths (copper and lead). There are two dryers for handling zinc concentrates and one each for copper and lead concentrates. The dryers are heated by burning natural gas. Each zinc dryer handles 1,000 t.p.d. and the copper and lead dryers 750 t.p.d. each.Multiple hearth dryers are unusual in the base metal mining industry and the reasons for selecting them in preference to rotary dryers are as follows:1) The concentrates could only be filtered to 15 to 17 percent moisture. These sloppy filter cakes would be extremely difficult to handle in rotary dryers."

Jan 1, 1972

By L. Long

Stirred milling of nickel laterites offers possibilities for improving liberation and selective size reduction of soft nickel-bearing minerals in laterites. Batch grinding tests were performed in a Netzsch LME4 stirred mill on siliceous goethitic (SG), goethitic (G), and saprolitic (SAP) nickel laterite samples (- 2000 ?m particle size) to evaluate the effect of stirrer speed, solid content, water salinity and grinding time. A fine mineral product (-38 µm) was used to evaluate the effect of selective grinding and Ni upgrade. The optimum grinding time for the highest Ni upgrade was 0.25 min, 0.1 min and 0.1 min for the SG, G, and SAP nickel laterite, respectively. A new feed (38-2000 µm) for each nickel laterite sample was prepared for batch grinding tests under the optimum grinding conditions. Upon grinding the 38-2000 µm feed, the - 38 µm product confirmed the effect of selective grinding and nickel upgrade. Size classification followed by stirred milling is a suggested process for Ni upgrade. The best Ni upgrade result was achieved on the SG nickel laterite among the three samples. The Ni grade increased from 0.85% to 1.37%, with 27.8% Ni recovery. Bottle roll leach tests showed that for SG and SAP samples selective grinding had no dramatic effect on Ni extraction due to the slow leach rate of hard mineral particles. Stirred milling of G sample increased the surface area of goethite, resulting in higher Ni extraction. Gravity concentration through a Knelson Concentrator was not effective in the further treatment of the stirred milling products either due to the poor operating conditions or due to the mineralogy characteristics of the feed samples. The energy requirement in the stirred milling was investigated. The first pass of the signature plots study is critical for the purpose of selective grinding, because the best result on selective grinding is achieved in the early stage of the grinding process.

Aug 1, 2013

NANA Accepts Mining ­ 1974 - Leadership presented mining option to people ­ Community meetings; recognized need for cash economy ­ 1979 - Poll shows consensus in favor of mine development ­ 1980 - Shareholders approve mining; Congress approved land selections

May 1, 2002

By William James Kempson

This paper discusses ore handling systems in shafts. These are considered from the loading facility at shaft bottom all the way through to the discharge mechanism in the headframe. These systems will be discussed from the following perspective: i. Intrinsic safety of the systems ii. The efficacy of the systems to perform consistently iii. The maintainability of the systems iv. Overall system cycle times Particular emphasis is placed on the following specific areas: 1. The Shaft Bottom Loading Facilities The various shaft loading systems currently in use are discussed, the selection parameters surrounding these are quantified and the specific selection criteria are outlined. 2. The Various Skip Configurations In this section the various skip configurations in use around the world will be described and the specific design details associated with these will be highlighted. The advantages and disadvantages of these systems will be compared and the overall efficacy of these will be discussed. 3. The effect of the loading and skip configurations on the Load Cycle Times. The overall cycle time which can be achieved by a shaft system is strongly dependant by the speed and efficiency with which the ore can be loaded and transported out of the mine. The potential of the various systems to be optimized will be discussed. The emphasis of this paper is to highlight the lessons which have been learned with respect to ore transport system design and provide a common basis against which these can be compared in future applications.

May 1, 2013

By L. C. Hsu, H. F. Jr. Bonham, M. O. Desilets, P. J. Lechler, J. G. Price, L. J. Garside

Abstract-Geochemical background levels have been established for unmineralized sedimentary rocks that are elsewhere the hosts of Carlin-type gold deposits in the Getchell Trend. The Paleozoic rocks in the Winnemucca Quadrangle consist predominantly of the lower Paleozoic siliceous and clastic sequences that were carried eastward along the Roberts Mountains thrust during the Late Devonian and Early Mississippian Antler Orogeny and the late Paleozoic Havallah and Pumpernickel sequences brought along the Golconda thrust eastward during early Mesozoic Sonoma Orogeny. Over 260 rock samples were collected from the Paleozoic sequences. Major and trace elements were determined by instrumental methods best suited for the specific elements. The general geochemical features of the Paleozoic sedimentary rocks are discussed in detail with reference to the data of average abundances of elements in sedimentary rocks. The background and threshold values of certain trace elements in sandstone, shale, and carbonate rock of one formation, as well as back- ground levels for the entire sequence were obtained. The characteristic geochemical features of the Paleozoic rocks in this area include: consistently high Ba and low Au contents (1.1 ppb, 1.5 ppb, 1.1 ppb Au for average sandstone, shale and carbonate, respectively); generally low contents of those elements which may be of environmental concern such as As, Cd, Hg and Pb. Plots of major and trace elements suggest that the majority of the Paleozoic clastic rocks are related to a passive- margin tectonic setting. Samples with gold values higher than threshold are considered to have been affected by hydrothermal alteration related to gold mineralization. Most of these samples generally also have higher values of Sb, Hg, V and/or As. These observations support the use of such elements as pathfinders for gold, although V has not been identified as such before. Ba is not effective for gold exploration in this area due to the generally high background value of Ba, even though it may be an important pathfinder elsewhere.

Jan 1, 1995

By H. Clare Horwood

"Three types of structures, the main shear zone, the north shear zone, and a series of hanging-wall fractures, contain all the orebodies so far discovered at the McKenzie Red Lake mine. Lenses and veins of quartz in these zones and fractures are the sources of the ore. The ore-bearing structures are unusual in that they are in a complex intrusive mass known as the McKenzie-Gold Eagle stock. They are believed to have been produced by compressive stresses from the south andsouthwest.The mine is on the northeast side of McKenzie island, in Dome township in the central part of the Red Lake area. The original discovery, the main shear zone, was made in 1928, about 3 years after the property was staked, by M. L. Bouzan who was in charge of prospecting and development work on the property. Subsequent diamond drilling and underground exploration led to the installation of a mill, which came into production early in 1935. The hanging-wall fractures were found branching out from the main shear zone during development work on the 350-foot level. The north shear zone was discovered in 1940.From 1935 when the mill began operation until the end of 1946 total production from the mine was approximately 269,349 oz. gold and 69,317 oz. silver, having a value of $9,679,739, recovered from 823,527 tons of ore.GENERAL GEOLOGYThe McKenzie-Gold Eagle stock has a total length of approximately 1 ½ miles and a width of about ½ mile. It was intruded into a complex synclinal fold in Timiskaming sediments. The sediments, which have been cut in only one place in the underground workings, are principally wellbedded greywackes. The stock is composed of large masses of diorite and granodiorite, a small mass of hornblende pyroxenite, and basic dykes of two ages. The diorite occurs as irregular masses in large measure surrounded by the granodiorite that it intrudes. It contains tabular crystals of andesine, having a maximum length of3/4 inch. The hornblende pyroxenite is an elongated lens or dyke in the diorite. The granodiorite masses occupy about two-thirds of the stock. Along its eastern side the main mass tends to become darker and more dioritic toward the diorite contact.Basic dykes of pre-vein and post-vein age are the youngest intrusive rocks at the mine."

Jan 1, 1954

By W. T. Boyes, J. M. Harrison

"Squall Lake Gold Mines, Limited, owns a group of claims at Squall lake, northern Manitoba, about 75 miles east of Flin Flon and 3 to 4 miles north of the Nor-Acme mine at Snow lake. Gold mineralization was discovered in this locality several years prior to 1944, but it was only in that year that a comprehensive examination of the occurrences was begun. Development work to the end of 1946 has been encouraging and the deposits show interesting relations to rock structure.GEOLOGICAL SETTINGThe gold occurs in a sill of biotite-hornblende diorite at or near its contact with gneisses derived from arkosic sediments . In detail, the contact between the diorite and the arkose to the southeast of it is irregular, with interfingering of the two rock types. On the northwest side of the sill, between it and Squall lake, the rock is staurolite schist (see accompanying sketch-map).Several mineralized shear zones are known, of which those shown are the most important. Within the zones, the diorite is silicified and somewhat carbonatized. Fairly coarse arsenopyrite is the chief sulphide mineral in these zones but, locally, they contain also pyrite and pyrrhotite. Where quartz and chlorite are present, rather coarse gold is associated with them. In that part of the main zone where gold assays have been most consistent, the diorite is rich in albite."

Jan 1, 1954