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By Rosa G. de Pena

From the MAP3S Precipitation Chemistry Network data bank five years of data from January 1, 1977 to December 31, 1981 have been analyzed. No definite trend has been observed in the concentrations and the total depositions in the analyzed period. Comparison between the weekly and event samples show that the weekly samples could underestimate the total deposition. Preliminary results show that there is a reasonably good correlation between the precipitation composition and the emissions feeding the air in which the precipitation is formed.

Jan 1, 1983

By Michael H. Leon, John A. Organiscak

Controlling worker dust exposure on longwall mining systems is difficult because the working face area serves as an immediate return during the mining cycle and the amount of airborne dust generated is directly related to production. Since improvements in longwall mining technology have significantly boosted production levels, additional technology is needed to control the airborne respirable dust generated at present and future production levels. One concept to reduce longwall worker's dust exposure is to maintain two splits of air at the face -- a clean intake split in the workers walkway, and a return (dusty) split over the face conveyor. The U. S. Bureau of Mines has recently investigated a concept to overcome the visibility handicap of face partitions by utilizing a permeable polyester mesh. The mesh material was anticipated to provide adequate air-splitting capabilities as long as the pressure differential between the face and worker walkway was minimal. Initial testing of this concept at the Bureau's Lake Lynn Laboratory showed that notable reductions could be achieved with a 1/8 in (3.18 mm) and 1/16 in (1.59 mm) mesh opening size. Dust reductions at 100 ft (30.5 m) and 200 ft (61.0 m) downstream of source were 58 and 36 pct, respectively, for the 1/8 in mesh and 79 and 55 pct, respectively for the 1/16 in mesh. Longwall application of the 1/8 in mesh showed similar results to the Lake Lynn Laboratory tests. A flame retardant mesh was used underground with portable lighting mounted on the shearing machine for face side lighting.

Jan 1, 1993

By Kevin Vander Tuig, Tim O’Rourke, Rick Vincent, Doug Lopata, Kellie Rotunno, Dan Dobbels

"The Northeast Ohio Regional Sewer District (NEORSD) was required under the Federal Clean Water Act and U.S. Environmental Protection Agency’s (U.S. EPA) Combined Sewer Overflow (CSO) Control Policy to develop a Long Term Control Plan (LTCP) to reduce or eliminate overflows from its permitted CSO outfalls. The LTCP was completed in 2002. Key components of the plan include: 26 miles (42 km) of deep storage and conveyance tunnels providing a total CSO storage volume of 325 million gallons (MG) (1.2 billion liters); over 30 miles (48 km) of consolidation sewers to route CSO control flows to the tunnels; and associated diversion/inflow control structures and drop shafts. Final design and construction of the initial phases of the LTCP are completed or underway. Advanced planning of the final phases began in April 2013. This paper summarizes this advanced planning process and, specifically, how hydraulic performance and tunnel design and construction considerations were balanced to eliminate unnecessary projects and shafts, reduce implementation risks, and reduce program costs by approximately $650 million. BACKGROUND The Northeast Ohio Regional Sewer District (District) serves an area of approximately 350 square miles (SM) (907 km2), including combined (81 SM; [210 km2]) and separate (269 SM [697 km2]) sewer systems that discharge to three wastewater treatment plants in the greater Cleveland area. The service area, shown in Figure 1, is divided into three districts—Easterly, Westerly, and Southerly—each having its own interceptor system and treatment plant, ranging in wet weather treatment capacities from 100 to 735 million gallons per day (MGD) (378.5 million to 2.8 billion L/day). The system includes 124 permitted combined sewer overflow (CSO) outfalls overflowing into the region’s tributary streams, Cuyahoga River, and Lake Erie."

Jan 1, 2016

By Nawal Kishore, Nilesh Pratap Singh, Amit Kumar Verma, Vikram Seervi

In India, despite its natural abundance, demand for coal exceeds its countrywide supply due to failure to achieve high production targets, especially in opencast mines, which are responsible for 94.98 percent of total raw coal production in the country. Employment of technological solutions, such as surface miners, is key to achieving higher coal production and productivity in an environmentally friendly manner, especially in populated areas adjacent to the mining zone. This technology eliminates blast hole drilling, blasting and primary crushing units, thus reducing related environmental hazards like ground vibration and fly rocks.

May 1, 2023

By Wen-Long Cai, A. Frederick Banfield

This paper investigates, through case studies on a porphyry copper and a coal deposit, the differences and relevances between an approximate production schedule approach, i.e., the best case and the worst case schedules and a practical production schedule approach. The comparisons were with regards to: 1) choosing an optimum ultimate pit size, 2) determining processing capacities, 3) selecting 'optimum' cutoff grades, and 4) blending. The comparison criteria was to maximize the project net present value. Conclusions were drawn based on the study results.

Jan 1, 1996

By Robert C. Sutter

In 1958, it became obvious to some of us in the solution mining business that there were certain problems in connection with our sodium chloride brining operations which were industry- wide. These were the types of problems which, while they were important to the safe and economical operation of our salt brining operations, were not such that their solutions would give an individual company a great competitive advantage over his competitor; and since they involve the safe and efficient mining of a natural resource, it was obvious that the answers would, in any event, be shared industry-wide. Since we were dealing with underground solution mining and, consequently, unseen and remotely controlled operations, the problems are formidable and the solutions difficult. While all of us were doing work to improve our operations, none of us could justify the expenditures necessary for basic research in these areas. Consequently, the idea was conceived of research sponsored by many companies with the same problems. In 1960, 11 companies entered into a' formal agreement to jointly support research on a specific problem of sodium chloride solution mining. The project to be undertaken was the development of a method for measuring the size and extent of underground solution cavities in sedimentary salt beds. It was agreed that all research was to be performed by independent research organizations. A part-time consultant or administrator was retained to administer the research contracts and to provide technical advice.

Jan 1, 1966

By R. W. Reisinger

An historic underground copper mine in Wyoming is discharging neutral but copper-laden water into a pristine creek. The EPA-deferred site qualifies for reclamation by the Wyoming Abandoned Mine Land (AML) program; restoring the discharge so that the creek can eventually support a trout fishery is the cleanup goal. Hydrological and geochemical investigations underground have suggested two sources of mine water: one clean and the other copper-containing. Results of bench-scale and pilot-scale tests support the viability of using low-cost passive treatment techniques to reduce copper concentrations in the near-freezing mine discharge.

Jan 1, 1998

By Peter J. Rafferty, Friedrich Steinhäusler

INTRODUCTION The Nuclear Energy Agency plays an active role in promoting international cooperation among its member countries in the field of nuclear energy. In addition to various other functions, it plays a major role in encouraging harmonisation of government regulatory policies and practices, promoting exchange of information, and coordination of research and development in the field of radiological health and safety associated with nuclear fuel cycle activities. The work of the Agency is carried out through a number of specialised standing committees. In particular, the Committee on Radiation Protection and Public Health (CRPPH) is responsible for the Agency's activities concerned with radiological protection and related environmental problems. Its functions include review and discussion of national radiation protection policies and practices, review of developments in radiological protection, interpretation of ICRP recommendations and the study of the means of their translation into practical applications, including the establishment of radiological protection standards. Its functions also include the preparation of technical studies and reviews on specific problems requiring attention, and coordination of further research and development at the international level. Major attention is presently being given to the NEA programme of work on problems associated with radiation protection and environmental impact of nuclear fuel cycle activities, with particular attention to the front-end (uranium mining and milling) and the back-end (waste management) of the fuel cycle. In this context, the increasing attention that has been given in several countries to the problems associated with the exposure of man to radon, thoron and their daughters, and with their dosimetry and measurement, were readily appreciated by NEA, which began an active programme of work in this field in 1976. Because of the detrimental health effects,as demonstrated by epidemiological studies,caused by prolonged exposure to excessive levels of shortlived daughters of radon, particularly in poorly ventilated underground mines, the bulk of attention and needed effort has been focussed on radon and radon daughters in uranium mining. In certain countries some concern has been expressed also about the significant levels of exposure experienced by workers in non-uranium mines,and members of the public who live in particular areas or in dwellings built with particular materials which produce higher than average levels of radon and radon daughters. However, at the time of the first NEA involvement in this field it was considered that one of the most urgent problems to be solved was that of ensuring adequate personal dosimetry for uranium miners. Consequently, the NEA was urged to organise a specialist meeting on personal dosimetry and area monitoring for radon and radon daughters to provide an international forum for exchanging information and reviewing problems in this field. The meeting was held in Elliot Lake, Canada, in October 1976. A second specialist meeting, on the same subject, was held in Paris, in November 1978, to review further developments in this area. These meetings demonstrated that the overall problem associated with exposure to radon and radon daughters had many facets, each of which in recent years has been the subject of considerable attention in many countries for different reasons. It emerged from the meetings that further work was required on a variety of issues in two main areas: 1) dosimetry 2) metrology and monitoring. Conclusions and recommendations which emerged from the two NEA specialist meetings were discussed by the CRPPH. As a consequence the Committee approved, in September 1979, a detailed programme of work in the area of dosimetry and monitoring of radon, thoron and their daughters, and approved the setting up of an international Group of Experts on Radon Dosimetry and Monitoring to undertake the work. The work has been divided into two phases - phase I, on dosimetric aspects, and phase II, on metrology and monitoring aspects. The terms of reference of the work are given in Appendix 1. A list of national representatives on the Group of Experts on Radon Dosimetry and Monitoring is given in Appendix 2; many of these persons are participating here in the Conference. The Group of Experts met for the first time in April 1980 and met again in September 1981. The work of phase I is nearing completion and a report is expected to be submitted soon to the CRPPH for its consideration. Three technical papers providing interim information on the study appear elsewhere in the proceedings of this Conference. The papers cover the three principle areas examined in the study so far: 1) dosimetric aspects 2) review of the "working level" 3) review of objectives and requirements for measurement and monitoring of radon, thoron and daughters. The authors, their affiliations, and the titles of these papers are listed in Appendix 3. A brief overview follows giving the principal results.

Jan 1, 1981

By A. G. Mayton, L. Adler

The paper under discussion provides an excellent and concise study of compartment ergonomics for thin seam equipment. However, in accomplishing this, some very important operational aspects were ignored. Since these are likely to be determinant, the authors' response is solicited. The novel shuttle car with its cross-car, end-mounted compartment is operationally very different from the current one. The latter can be considered a highly mobile extension of the continuous miner or loader, with a pass-through conveyor, dump boom, and extra storage. As such, the vehicle's kinematics are the simple "I," or shuttle pattern, bent for going around pillars, with an intermediate stop at the "change-out point" (Adler, 1986 ). The action of the cable reel adjusts well to this pattern. The proposed shuttle car's motion either superimposes a "Y," time is lost (5 seconds) for each cycle, space is needed, line of sight is compromised, and a cable anchor is probably required at the dump. A chute is almost prohibitive in construction time and cost. The lack of a dump boom further curtails flexibility in the proposal. The value of a standard hand and opposite standard hand configuration also needs consideration. Many front-end loaders have a rocker (overshot) capability that is designed to achieve an "I” pattern. And crawler loaders sometimes use a side dumping bucket variant for the same purpose. These examples indicate the pattern's importance. For underground, thin seam application, the ram car has become popular. This is an articulated truck, battery-powered, and with an ejector dump. Its operational patterns would be similar to the novel shuttle car, except without the loading flexibility provided by a conveyor. Since the cab location of the proposed shuttle car largely obviates some of the major advantages of the present shuttle car, the question arises whether this configuration could be adapted to the current ram car and scoop

Jan 1, 1991

By L. Adler

The paper under discussion provides an excellent and concise study of compartment ergonomics for thin seam equipment. However, in accomplishing this, some very important operational aspects were ignored. Since these are likely to be determinant, the authors' response is solicited. The novel shuttle car with its cross-car, end-mounted compartment is operationally very different from the current one. The latter can be considered a highly mobile extension of the continuous miner or loader, with a pass-through conveyor, dump boom, and extra storage. As such, the vehicle's kinematics are the simple "I," or shuttle pattern, bent for going around pillars, with an intermediate stop at the "change-out point" (Adler, 1986). The action of the cable reel adjusts well to this pattern. The proposed shuttle car's motion either superimposes a "Y," time is lost (5 seconds) for each cycle, space is needed, line of sight is compromised, and a cable anchor is probably required at the dump. A chute is almost prohibitive in construction time and cost. The lack of a dump boom further curtails flexibility in the proposal. The value of a standard hand and opposite standard hand configuration also needs consideration. Many front-end loaders have a rocker (overshot) capability that is designed to achieve an "I" pattern. And crawler loaders sometimes use a side dumping bucket variant for the same purpose. These examples indicate the pattern's importance. For underground, thin seam application, the ram car has become popular. This is an articulated truck, battery-powered, and with an ejector dump. Its operational patterns would be similar to the novel shuttle car, except without the loading flexibility provided by a conveyor. Since the cab location of the proposed shuttle car largely obviates some of the major advantages of the present shuttle car, the question arises whether this configuration could be adapted to the current ram car and scoop.

Jan 1, 1990

By L. Alan Weakly

Coal mines and power plants utilize different methods to control dust for the safety of their workers and to protect their installations. The methods that they use are limited by the Environmental Protection Agency or the states in which they operate. Now there is a new technology for controlling dust at conveyor transfers! The Passive Enclosure Dust Control System utilizes several proven technologies to mitigate fugitive dust. This new system has been proven to be four times more effective than standard enclosures utilizing bag house collection and is considerably less expensive to install and operate.

Jan 1, 2000

By Gamal Rashed, Tim Miller, Nicole Evanek

High horizontal stress has been identified as a critical factor affecting roof stability in underground mines, particularly when the immediate roof consists of weak or laminated rock. Numerical models were employed to better understand the influence of caprock thickness, cutting sequences, and the orientation of driving direction relative to maximum horizontal stress on roof stability in underground stone mines. These models were calibrated based on field observations of roof falls from the study mine. The findings of this study enhance our understanding of roof stability under high horizontal stress and contribute to reducing the risk of roof falls in underground stone mines.

Feb 1, 2025

By Alain GSELL

The aluminous nature of the laterites capping the Minim Martap plateaus - named after two neighbouring villages - and the small nearby upland of Ngaoundal, was discovered by the Cameroon Mines and Geology Division in 1958. These deposits of worldwide importance, are located in the Ngaoundere region, some 500 km (300 miles) north-east from the port of Douala (as the crow flies). They constitute the major part of the Cameroonese mining potential. The study of the deposits and their economic development has been entrusted to SEBACAM, Societe d'Etudes des Bauxites du Cameroun, a company in which the Cameroon government participates. The bauxites originate from the transformation into laterite of lavas which covered a Precambrian basement during the Upper Cretaceous period and the Lower Tertiary era. The entire Minim Martap deposit comprises bauxite plateaus ranging in area from a few acres to several square miles. The average thickness of the bauxite layer varies from 10 metres at Minim Martap to 17 metres at Ngaoundal. The mineral constituents of the bauxite are gibbsite trihydrate, kaolinite and the usual iron and titanium oxides. Treatment of the ore does not involve any particular technical problems. Proven exploitable reserves amount to 560 million tonnes of dry bauxite with a reactive silica content of 1.80% and an available alumina content of 43.70% at Minim Martap, and 120

Jan 1, 1984

By Robert Rautenberg, Ted Budd

The paper will discuss the successful construction of the largest dollar value ($194.5 million, U.S.) TARP (Tunnel and Reservoir Plan) project built to date for the Metropolitan Water Reclamation District of Greater Chicago. The mining and lining of the 18.5km (11.54 miles) tunnels will be emphasized. The tunnels were driven utilizing three TBMs ranging in size from 9.85m (32.33 ft) to 3.70m (12.16 ft) in diameter. The operations surrounding the 11,546m (37,876 ft) long 9.85m (32.33 ft) diameter tunnel will be highlighted. A total system concept was utilized to attain mining rates up to 29.3m (96 ft) per shift and lining productions of 58.5m (192 ft) per day. The reliability of these systems was instrumental in the completion of the project more than a year ahead of schedule.

Jan 1, 1995

By Jamal Rostami, Ebrahim Farrokh

Selection of tunneling method, specially the use of shielded machines for application in deep rock tunnels can be heavily impacted by presence of ground convergence and squeezing conditions. Tunnel convergence is a function of ground conditions (i.e., rock mass behavior, groundwater, in-situ stresses), size of the opening, and TBM operational parameters. The case study of Ghomroud water conveyance tunnel project in Central Iran, which is under construction using a double shield TBM, is used to examine the effect of rock parameters on tunnel convergence and hence on the need for over excavation and shield lubrication to avoid problems with the shield getting stuck. Although it is impractical to perform a continuous assessment of rock mass conditions within the shield or in the lined tunnel, results of field observations and subsequent studies show that the amount of the tunnel convergence has direct correlation with the percentage of fines and large rock fragments in the muck and TBM thrust/torque/ROP. These relationships have been examined and will be presented in this paper.

Jan 1, 2007

By John W. Tieman

Coal is a term applied to vegetable matter (trees, grasses, etc.) which was subjected to heat and pressure through geologic ages. This resulted in a change in both the physical and chemical properties. Because its chemical composition is variable, geologists classify coal as a heterogeneous mineral rather than a homogeneous mineral. Peat represents the initial, unconsolidated stage in the development of coal. This coalification continues with time and the application of temperature and pressure to lignite, subbituminous, bituminous, and anthracite toward the theoretical graphite end member.

Jan 1, 1981

By J. Le Gac, P. Zettwoog, J. Brenot, J. W. Piechowski, J. C. Nenot

INTRODUCTION The components of the radiological hazard in uranium mines are: 1. exposure to radon and its short-lived daughters 2. exposure to long-lived ore dust 3. external irradiation With usual ventilation rates, the dosimetry relative to the first component only requires to know each miner&apos;s exposure to a potential energy of short-lived radon daughters, (EXP[a]). Presently in France, (EXP [a]) is determined monthly from radon concentration measurements. This is an indirect method based on ambient monitoring. After technical improvements achieved during the last years it is now possible to measure (EXP [a] directly with an individual portable monitor developed by the CEA. The purpose of this study is to analyze and compare monitoring results obtained by these methods. DETERMINATION OF INDIVIDUAL MONTHLY EXPOSURES TO[ a] POTENTIAL ENERGY OF SHORT-LIVED RADON DAUGHTERS [(EXP a) amb, by ambient monitoring] In this case, it is necessary to know individual monthly exposures to radon, (EXP Rn). As mentioned by Pradel, J.,et al., 1976, (EXP Rn) is estimated for each worker from informations both on radon concentrations (CRn) measured as described by Pradel, J., 1962 and times (t) elapsed in the various workplaces. (EXP Rn) is obtained by summing up the elementary radon exposures CRn x t relative to all the workplaces where the miner was successively engaged during the month. (EXP Rn) values are then corrected by an average equilibrium factor of 0.17 deduced from many measurements and taken as representative for all the French mines. Finally: [ ] (EXP [a])ind are obtained directly with an individual portable instrument described by Chapuis, A.M., et al., 1972. Samples of the air breathed by the miners are pumped continuously and radioactive aerosols containing the short-lived radon daughters are trapped on a filter. The principle of the measurement lies on track-etch detection of the a particles emitted by the deposited material. The technical aspects have been described by Duport, P., et al., 1980a, Mouden, A., et al., 1980 and Chapuis, A.M., 1980. As mentioned by Duport, P., et al., 1980, fiability is good. Indications on measurement reproducibility are given by Pradel, J., et al., 1977. PRESENTATION OF THE STUDY The underground miner population of a French mine was followed during a period of 8 months (October 1978 - May 1979). Monthly exposure values for each miner determined either by ambient or individual monitoring, (EXP [a])amb or (EXP[ a])ind, had been previously collected by Le Gac, J., 1980, who had also defined miner categories according to the characteristics of the work performed. Four groups are considered here, the "whole mine" and three categories as described in table 1. Data on the individual monthly exposures,(EXP [a])ind and (EXP [a])amb, were taken again to analyze the individual cumulative exposures instead of the "month by month" values. The influence of the mean habits of each individual on its surveillance results is thus taken into account. Each miner has a cumulative exposure as an individual of the "whole mine" and as an individual of each category in which he has worked. The results obtained by ambient or individual monitoring were analyzed (characteristics and adjustements of the distributions) and then compared (description of the discrepancies observed). Obviously, such a study is possible only if all the exposures are cumulated on a same duration. As miners have not worked during the same number of months in the course of the data collecting period, one must considerer the individual average monthly exposures, [(EXP a)]amb and[ (EXP a)]ind, instead of the individual cumulative exposures, which is typically the same thing. To be sure that the exposure values of a given group (A, B, C or D) are representative, only those miners really present for at least 3 months in this group were taken into account. Finally, each individual of the "whole mine" and of the various work categories has a pair of average monthly exposure values : [(EXP a)amb] determined by ambient monitoring and[ (EXP a)ind] deduced from the track-etch recording of the individual portable monitor. Let a miner be engaged during n months[ (3 < n < 8)] in a group, the following relations then apply : [ ]

Jan 1, 1981

By M. J. Gregory

The Pebble Cu-Au-Mo deposit in southwest Alaska is one of the world&apos;s largest porphyry deposits. The western part of the deposit was discovered by Cominco America in 1987, who sold the project to Northern Dynasty Minerals Ltd., in 2001. Northern Dynasty discovered the high-grade eastern part of the deposit in 2004 and went into a 50:50 partnership with Anglo American PLC in 2007, forming the Pebble Limited Partnership (Lang et al., 2008). The Pebble Limited Partnership has continued to delineate the deposit through diamond drilling with the most recent resource estimate released in February 2010 (Pebble Limited Partnership, 2010). The Pebble deposit mineral resources comprise 5.94 billion tonnes of measured and indicated resources grading 0.78% Cu EQ, containing 55 billion pounds of copper, 67 million ounces of gold and 3.3 billion pounds of molybdenum. Also delineated are 4.84 billion tonnes of inferred mineral resources grading 0.53% Cu EQ, containing 25.6 billion pounds of copper, 40.4 million ounces of gold and 2.3 billion pounds of molybdenum (Pebble Limited Partnership, 2010). Resources are calculated using a 0.3% Cu EQ cutoff. GEOLOGY AND MINERALIZATION Deposit Geology The Pebble deposit is located in the Kahiltna terrane, between terminal strands of the north-east-striking Lake Clarke strike-slip fault. This fault represents an accretionary boundary and separates the Kahiltna terrane to the north-west from the Peninsular terrane to the south-east (Lang et al., 2008). The Pebble deposit represents a large magmatic-hydrothermal system centered on a group of 90 million year old porphyritic hornblende granodiorite intrusions. An east-west cross section through the southern part of the deposit (Figure 1A) shows the typical relationships between the various rock units which host sulfide mineralization. Sub-parallel ~96 million year old granodiorite and diorite sills were intruded into siltstones of the Jura-Cretaceous Kahiltna flysch. In the west, these sills were cut by a ~96 million year old alkalic intrusive complex composed of porphyritic monzonites and monzodiorites and related intrusion breccias (Bouley et al, 1995). The mineralized 90 million year old hornblende granodiorite intrusions cut all rock types and comprise four small stocks in the western part of the deposit and a larger pluton in the eastern part of the deposit. Recent deep drilling indicates that these intrusions coalesce at depth. The strongest porphyry-style mineralization is centered on the eastern granodiorite pluton and extends into the surrounding rock units (Figure 1A). The western half of the deposit crops out at surface, whereas the eastern side is un-conformably overlain by a cover sequence of Late Cretaceous to Eocene sedimentary and volcanic strata. The deposit was tilted 20º to the east during the Eocene.

Jan 1, 2012

During the past decade, international mining companies have descended on South America. Countries like Chile, Brazil and Peru have seen billions of dollars in exploration and development funding turn their once meager mineral industries into mining giants that have become the envy of the world. Part of this outpouring of foreign investment in those countries has been because each has privatized its state-owned mining companies and has liberalized its foreign investment laws. In addition, they have rewritten their mining codes to encourage minerals development and passed new tax laws that have made natural resource development more attractive. Now these same international mining companies are turning their attention to Argentina. This a country that, like Chile, Brazil and Peru, has a wealth of largely un- tapped mineral resources. And Argentina wants its share of the foreign investment that its neighbors have enjoyed. With that in mind, ministers of Argentina&apos;s natural resource agencies came to Denver, CO to meet with mining executives and pitch their country&apos;s mining industry. The meeting, attended by about 200 people, was sponsored by the US Trade and Development Agency and organized by the World Trade Center Denver. Others involved were the Colorado Mining Association, the Colorado International Trade Office and the Secretariat of Industry, Commerce and Mining of Argentina. The following is a summary of a report on Argentina&apos;s mining industry. It was prepared by Anderson & Schwab Management Consultants and distributed to attendees as part of the meeting&apos;s program.

Jan 1, 1998

By John Frostiak, Igor Gonzales, Kenneth G. Thomas, Ken Manning

The Pierina deposit was acquired in August 1996 when Barrick Gold Corporation purchased Arequipa Resources, a junior mining company with extensive land positions in Peru. At the time of acquisition, Arequipa ha.d developed two exploration tunnels and drilled 9 exploration holes on the property. Metallurgical tests, conducted on samples taken from the tunnels and the exploration holes indicated that the ore was amenable to heap leaching. Barrick's exploration team recognised from the outset, the potential of the mineralisation and convinced Barrick's senior management that this was indeed a world class deposit that should be pursued. On November 25, 1998, the fi was poured at Pierina, 27 months from the time of acquisition. During that period BmTick completed its exploration programme, prepared a development plan including capital and operating costs, production profiles and cash flow forecasts, and a schedule to develop a mine and construct a leach pad and gold recovery plant, including all supporting infrastructure. All permits and environmental approvals were obtained and all necessary land was acquired. The project was completed on schedule and under budget. This was the first greenfield mine development for Barrick outside of North America. This paper details, mainly, the research and development, engineering, construction and commissioning of the metallurgical process facilities.

Jan 1, 2000