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A series of small scale tests have been conducted to evaluate the effect of micro-fracture development, imposed by blasting, on the material properties of the rock as well as its resistance to crushing and grinding. The uniaxial compressive strength, tensile strength, Poisson?s ratio, P-wave, Swave velocity, point load test index, crushing and grinding work indices were evaluated for samples without any blasting load and for samples which had received a variety of blast loads ranging from a single impact with low strength detonating cord, to combination of impacts at different times and significant impacts with powder factors close to those used in practical blasts. It was shown that the rock mechanics parameters change even at low impacts, suggesting easier crushing of the rock. Damage values appear to be affected by timing as stress wave superposition affects the damage process. Fragmentation is achieved at higher impact levels while work index modification of the fragments is also observed when high powder factors are used, suggesting improvements in grinding.

May 1, 2003

By Mikael Ramström

In 2002 Atlas Copco Rock Drills AB released the new RCS technology for all of its drill rig types. RCS opened the way for a new generation of computerized drill rigs based on modern, standard PC-computer technology. Drilling accuracy, information logging and reduction in manpower in some types and serviceability, have all taken a quantum leap forward when compared with previous generations of drill rigs. The RCS (Rig Control System) is modularised and distributed is accomplished by means of CAN-bus technology. This technology, which is well proven in automobile applications, forms the communication backbone of the rig. The modularity facilitates almost unlimited possibilities for the expansion and adaptation of drill rig functions.

May 1, 2003

?General Facts:Barrick?sFirst Mine in Peru Production started in November 1998 ?The Facilities:Open Pit, Primary and Secondary Crusher Valley Fill Heap Leach PadMerrill Crowe PlantRefinery Environmental Facts: High Rainfall - Average Annual Precipitation of 1,200 mm (47 inches) Rainfall Events: Common 20mm daily events High Altitude Site - Elevations range from 3900 to 4250m. Steep topography - Terrain ranges from 3:1 slopes up to cliffs. Water Issues: Sediment Control - Open Pit PAG Encapsulation - Waste Dump Stormwater control - Leach Pad Erosion Control Techniques ? Offsite impacts mitigation Social Issues: 11 communities surrounding the property Town of Huaraz

May 1, 2003

By Kent Zehr

Suncor Energy Inc. is an integrated producer and refiner of oil and gas headquartered in Calgary, Alberta. The bulk of revenue comes from the Oil Sands Group (OSG) operating in the McMurray formation of the Athabasca Oil Sands. Located some 25 kilometers north of Fort McMurray, Suncor OSG began life in 1967 as Great Canadian Oil Sands, the first operator to successfully enter commercial production of synthetic crude oils from the area. For most of the last decade, dramatic growth has been the standard mode of operation for Suncor OSG. Production of synthetic crude first reached 100,000 barrels per day in 1997 and less than five years later is averaging in excess of 200,000 barrels per day. Within this dynamic organization, Suncor Extraction is the business unit that processes run-of-mine ore into clean diluted bitumen for Upgrader feedstock. Extraction also delivers and places the barren sand and process affected water into tailings storage in one of several ponds from which water is recycled to support the various processes. For reference purposes, Extraction on a typical day currently receives more than 400,000 metric tons of oilsand ore, which is all processed to water based slurry for separation in one of two extraction plants. Separated tailings are disposed of as a slurry and the cleaned bitumen froth is diluted with naphtha and sent to tankage for storage until required by the Upgrading Unit. As a consequence, on a typical day Suncor Extraction pumps more than 1,000,000 tonnes of aggressive slurry into and out of the two extraction plants.

May 1, 2003

By P. H. Oliver

The current theory of how explosives fracture rock offers no explanation for the improvements in fragmentation and the reduction of fly rock and back break which occurs when an adequate inter-row delay time is used. Nor does it explain why fragmentation improves with rectangular drill patterns where the hole spacing may be as much as four times the hole burden. A new theory of rock fragmentation is proposed which builds on the existing theory. It offers rational explanations for the many blast effects which the current theory does not address and the need for adequate timing delays between rows. It improves on the design of inter-row delay timing by defining the length of free-blasted face needed in front of a hole when selecting the delay element which will provide an adequate inter-row delay time.

May 1, 2003

By James W. Cassie

The Snap Lake Diamond Project is located approximately 220 km northeast of Yellowknife, NT, Canada at an approximate latitude of 63?35?. The project location is within the zone of continuous permafrost; measured ground temperatures are about ?2?C at 10 to 20 m depth below surface. The site is located on a peninsula jutting into Snap Lake. The site is generally barren of vegetation, except for some isolated areas with low trees located in topographic lows and near the shoreline of Snap Lake. As part of phased evaluation process with regards to the mining project, an Advanced Exploration Program was undertaken in 2000 and 2001. This program included the underground extraction of a bulk sample of kimberlite, which was processed on site. A Processed Kimberlite Containment (PKC) area was required as part of this program. The area chosen as the PKC facility was a small inland lake, called Inland Lake #1, on the peninsula. Construction of the PKC area required the construction of two dams, one on either end of the lake. At the south end of the lake, Dam 1 was constructed partially on a talik and partially on continuous permafrost. Dam 2 was constructed entirely on permafrost. The effects of the remote location, selection of suitable construction materials and permafrost conditions on the designs of the dams are discussed. A description of the design elements and construction schedule are provided. A review of the performance of these two dams, in terms of settlement, deformations, pore pressures and thermal regime, over the last several years is provided.

May 1, 2003

By Mark Rantapaa

Measurable improvements in throughput have been documented at Barrick Goldstrike due to increased ore fragmentation through efficient drilling and blasting techniques. A decrease in throughput at the Autoclave, due to increasingly hard ore, was identified in early 2002. A team of individuals from the Open Pit and Process areas worked closely on the Drill-to-Mill (D2M) Continuous Improvement initiative to ensure that it would address the needs of both groups, with the target of actually improving throughput in future years, despite the projected harder ores. A series of tests were conducted to determine if adjustments to drilling and blasting could positively influence throughput. Better fragmentation and a subsequent increase in mill throughput were achieved through the use of: 1) Electronic caps for more precision and flexibility, as well as for allowing extremely fast shots. 2) Explosives with a higher velocity of detonation (VOD), to provide for improved shock energy. 3) Improved distribution of the explosives by decreasing pattern spacing. Early tests indicated a significant increase in throughput when processing identified harder ore. It is anticipated that the total process throughput (hard and soft ore) will increase by six tph in 2003 due to the improved fragmentation of the hard ore. Barrick Goldstrike?s D2M initiative includes roaster ?hard ore? (BWI >17), as well as autoclave ?hard ore? (BWI >15). Approximately six million tons of D2M material is expected be shot in 2003, a relatively small amount compared to the 150 million tons to be mined. The benefit of additional ounces produced should far outweigh the additional drilling and blasting costs.

May 1, 2003

By John E. Udd

In early 2000, CANMET-MMSL was engaged by the Ontario Ministry of Labour (OMOL) to conduct an international study of the practices, in several key mining jurisdictions, of determining the criteria that are used to decide when the wire ropes used in mine hoisting are to be retired from service. Subsequently, the writer visited key officials and institutions in Canada, the USA, the Republic of South Africa, the United Kingdom, Germany and Poland. Material from the Australian province of New South Wales and Hungary was also included. The report that resulted included, among other sections; (1) the history of wire rope and trends in manufacturing technology; (2) a review of mine hoisting practices; (3) the requirements as regards safety factors; (4) a review of the players and the inspection practices; (5) the criteria for rope replacement; (6) a look into the future to outline the developments that could take place in both hoisting and rope inspection practices in Canada; (7) recommendations. Subsequently, the report was issued as a book by OMOL, and as a CD-ROM by the Mining and Mineral Sciences Laboratories, Natural Resources Canada. In this paper the author presents the key findings and the recommendations made in the study.

May 1, 2003

By Joseph J. Poveromo

The blast furnace today continues as the primary production method of hot metal in large-scale steel production. The blast furnace process has been the target of repeated attempts to replace it with various process options, including direct reduction and coke-free smelting reduction. While these new technologies are being adopted in appropriate niches, the blast furnace has responded to the challenge by being amenable to continuous improvement. I will review the role of the blast furnace, major developmental and improvement trends, and then list the current important issues in ironmaking. I will outline the challenges to be faced by the blast furnace to maintain its position as the primary hot metal production process. The material presented here is an update of earlier presentations made in Stockholm, Sweden, 1996, Duluth, 1998 and Chicago, 2000.

May 1, 2003

By Robert Hamilton

Aur Resources is Canada's leading copper mining company with producing mines and development projects in North, Central, and South America. Copper production from Louvicourt Mine in Quebec, Quebrada Blanca, and Andacollo Mines in Chile had a record of 245 million pounds in 2001. Located 600 km North of Montreal, Louvicourt Mine is a joint venture between Aur Resources (30%), Teck Cominco (45%), and Novicourt (45%). Aur Resources is the mine operator with 280 employees working to produce a copper and zinc concentrate. In operation since 1994, the mine has produced a total of 12,606,000 metric tonnes of ore grading 3.6 % Cu, 1.5 % Zn, 26gr./m.t Ag, 0.9gr.m.t Au. This highly mechanized mine reached full production in August 1995 at 4,000 tpd. From 1996 to 2001, the average mine production rate was more than 4,300 tpd. The Louvicourt Mine continued its record of solid performance in 2002 and is expected to continue to do so for the balance of its 2.5 years mine life.

May 1, 2003

By Adrian Dance

The Antamina orebody is a geologically complex, polymetallic skarn located in the Peruvian Andes. A range of copper and copper-zinc ores are campaigned separately through the concentrator producing copper and zinc concentrates as well as lead and molybdenum by-products. Ore type classification at Antamina is based on chemical assays; geological or lithological variations are not considered. Consequently, each ore type demonstrates a wide range of concentrator performance. Antamina is currently implementing a system to track ore movements from the shovel face to the concentrator. Relatively sophisticated models of the ROM and coarse ore stockpiles ahead of the mill will be used to account for the variable delay between mining and milling. One of the numerous benefits of ore tracking is the ability to directly associate the measured concentrator performance with a physical location in the orebody. Using existing mine planning software, three-dimensional models can be created of such performance measures as metal recovery, concentrate quality, operating cost and reagent consumption. Such a database of information allows the true value of different ore sources to be determined. The value of an ore source is conventionally measured as metal content (individual or combined ?equivalent?) with a cut-off grade applied to indicate some base level operating cost. However, the true value of an ore source should include dynamic factors like haulage cost, reagent use, smelter penalties and even prevailing metal prices. If an ore source is considered from all perspectives rather than simply its potential to deliver value, the concept of ?ore? becomes more flexible. Any ore source that reveals itself to be unprofitable can be eliminated from the mine plan or possibly blended with others to improve its value. The ability to predict mill performance ? and thereby profitability ? is a powerful tool. In an operation such as Antamina, where managing ore sources, campaigns and the delivery of a variety of concentrates in a narrow timeline to customers is a daily challenge, prediction is the key to success and improved efficiency.

May 1, 2003

By Charles Tkaczuk

In order to remain competitive the mining industry must keep up with changes in technology. Many innovative technologies from the mining perspective are commonplace in other industries. A ?Global? review of technologies will often reveal existing technologies that can be innovatively applied in the mining industry. Industries, which are rife with proven solutions include, medicine, biotechnology, security, manufacturing, telecommunications, etc. This paper addresses the communications aspect of mining where greater productivity, lower costs and the ability to quickly react to mining related events is obtained through an increase in remote monitoring and operating control. A review of the communications systems in place globally reveals technologies that, with minimal modification, can be immediately applied to the mining environment. We discuss the concept, advantages and implementation of existing communications technology from an industry that is not usually associated with the mining industry. This technology will form the basis of a solid platform on which can be built a state-of-the-art process monitoring, control, and communication system. This lays the groundwork for providing one solution to the underground mining industry?s most difficult problem, establishing a reliable, maintainable and cost-effective underground bi-directional wired/wireless data, video and analog communications system. We need look no further than our own doorsteps to find such a solution. The cable that you see coming from the simple green or brown box on the boulevard into your home contains hundreds of television broadcast channels, FM radio channels and data channels. And if you have a set-top box, you are in control of it all. The Cable Television Broadcast Distribution System suppliers of today are at the leading edge of converging all the different methods of communications onto a common carrier, coaxial cable or fibre optic cable. There is no fundamental difference between providing a reliable communications network to a city/neighbourhood/home/personal computer than there is to a mining operation/underground level/equipment or person. The principle is the same. Only the application is different. Realizing this, we can capitalize on the efforts of other industrial sectors, to solve our communications problem. Where else can you find a solution to a problem that is mature, having been developed with the input of thousands of engineers, and having hundreds of millions of dollars spent on research and development, manufacturing, distribution, global presence and engineering support?

May 1, 2003

By Michael Samis

The real option valuation method is often presented as an alternative to the conventional discounted cash flow (DCF) approach because it is able to recognize additional project value due to the presence of management flexibility. However, these two valuation methods can be separated on a more fundamental level by their differences in risk discounting. Real option valuation applies the risk-adjustment to the source of uncertainty in the cash flow while the DCF method adjusts for risk at the aggregate level of net cash flow. This seemingly small difference is the reason why the real option method is able to differentiate between projects according to each project?s unique risk characteristics while the conventional DCF approach cannot. This paper provides an overview of the real options and DCF valuation frameworks and discusses the differences in risk discounting that exist between the two methods. Using grade-school mathematics, this paper clearly demonstrates how, with real options, a unique project risk discount can be calculated which is directly linked to the project?s unique risk profile. It also highlights why the DCF method fails in this regard and shows why a call to ?increase the Risk-Adjusted Discount Rate? is an incomplete solution at best. Finally, a heap-leach project and satellite reserve development project are valued with both techniques and the difference in investment conclusions is explained in terms of the risk-discounting concepts discussed here.

May 1, 2003

By Miguel Rutti

El presente trabajo señala la geología, litología y mineralización del yacimiento minero El Tapado del distrito Yanacocha, situado al norte de Cajamarca. Este se encuentra conformado por diferentes depósitos auríferos epitermales de alta sulfuración, los cuales se desarrollan dentro de un vulcanismo calco-alcalino de composición andesítica a dacítica de edad Mioceno y son correlacionables con la Formación Porculla del Grupo Calipuy. La geología del depósito está conformada por rocas porfiríticas (intrusiones) y flujos piroclásticos tales como tufos de cristales, tufos líticos y brechas piroclásticas afectados por eventos eruptivos de brechas freáticas - freatomagmáticas. Todas estas rocas han sufrido posterior alteración hidrotermal con ensambles típicos de sistemas tipo ácido-sulfato. La mineralización económica está controlada por procesos hidrotermales y se encuentra asociada a sílice masiva y sílice vuggy ( 1-10 g/t Au y estructuras de hasta 136 g/t Au ) y en menor grado sílice alunita y sílice granular (moderada a baja ley).

Apr 22, 2003

By Shaw Bill

The paper describes of the JORC Code in terms its background working environment and reasons for success, and provides references to papers which cover the subject in more detail. It then discusses the two major developments in Australasian reporting standards in the last two years: the revision of the 1999 Code, and the introduction in early 2003 of the “ROPO” (Recognised Overseas Professional Organisation) initiative. The purpose of the JORC Code is to provide a minimum standard for reporting of Exploration Results, Mineral Resources and Ore Reserves in Australasia, and to ensure that public reports on these matters contain all the information which investors and their advisers would reasonably require for the purpose of making a balanced judgement regarding the results and estimates being reported.

Apr 22, 2003

By Leandro Echavarría

El presente texto describe el sistema epitermal de Arcata, situado en Arequipa, Perú. Arcata es un distrito epitermal de sulfuración intermedia rico en plata y metales base, cuya mineralización se hospeda en vetas de rumbo predominante noroeste y movimiento principal paralelo a la inclinación que forman una estructura de fosa (graben). Las vetas poseen texturas de relleno de espacios abiertos como bandeados costriformes, en cucarda, crecimientos en peine y brechas, con ganga de cuarzo, calcita, rodonita y rodocrosita. Por su parte, los minerales de mena más comunes son galena, esfalerita, calcopirita, con los metales preciosos hospedados en sulfosales de plata (pirargirita y tetrahedrita). Asimismo, se ha identificado una compleja secuencia paragenética con varios pulsos responsables de la mineralización económica.

Apr 22, 2003

By Louis Gariepy

El presente trabajo describe las características geológicas actualizadas de Cerro Lindo como yacimiento del tipo de sulfuros masivos volcanogénicos (SMV) y propone un modelo genético de su formación que apunta a una deposición en parte -sobre el fondo marino y por debajo de él-, controlada por fallas sinvolcánicas dentro de un graben intra-cuenca volcánico-sedimentaria.

Apr 22, 2003

By Martin Williams

During the coming decade, many of the first generation of ‘super-pit’ gold and base metal mining operations in North and Latin America will reach the end of their economic lives. The closure of such pits in a manner which is environmentally sustainable presents a considerable challenge to the minerals industry. Pit closure often results in the partial or total inundation of formerly dewatered mining operations, and the resultant formation of lakes. The development of techniques for predicting, and controlling, the chemistry, groundwater discharge characteristics and long term hydrospheric impact of these lakes has become a critical aspect of pit closure planning. In this sense, the paper point out that Sleeper Mine was the first of a new generation of open pit gold mines developed in Nevada, USA. The closure of the Sleeper pit exemplifies the use of a range of pragmatic approaches to pit flooding, with applicability to mine closure at many other sites throughout the Américas.

Apr 22, 2003

By Frederick Felder

The paper point out the Angostura deposit is located in Colombia. The Angostura deposit, located within the Eastern Cordillera of Colombia is hosted by Triassic-Jurassic quartz monzonite and quartz diorite porphyries emplaced into Precambrian gneisses of the Bucaramanga Group. Silicification, pyritization, sericitization, alunite and pyrophyllite and other alteration and indicator minerals suggest a high sulfidation origin for the strong hydrothermal alteration. Major faults and shear zones occur in the area with NE, E-NE, E-W, WNW, NW and N-S directions. Analysis of geological results and structural modeling has also demonstrated that there is potential for additional high-grade ore shoots within the presently known mineralized structures. Delineating these structures should result in an increase of overall grade and contained ounces.

Apr 22, 2003

By Robert Shaw

"The paper point out the volcanogene and sediment-hosted base metal deposit from the Colombian cordilleras have been considered in the light of tectonogenic models for these deposit types, based upon the recent re-interpretation of the geology and tectonic assembly of the Northern Andean Block by Cediel and Cáceres and Cediel. Numerous distinct propitious metallogenic settings containing important but subexploredbase metal mineralisation are manifest as a result of the tectonic evolution of this northern-most sector of the Andes. Some examples include like a) Central African Cu (U) Belt - type mineralisation within the back-arc region of the early– middle Paleozoic Cordillerantype Quetame Orogeny, b) numerous SEDEX and Sediment-Hosted Zn (Pb-Ag) and Cu (Ag) styles of mineralisation associated with various phases of continental and continental margin rifting during the late Paleozoic to Mesozoic Bolívar Aulacogen, and c) various Cu-Zn-Pb (Au, Ag) Volcanogene Massive Sulphide manifestations associated with intra-oceanic magmatic arc development and accretionary tectonics during the Meso-Cenozoic Northern Andean Orogeny. "

Apr 22, 2003