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By Tony Szwilski

Indonesia has enormous mineral resources. Its population of more than 180 million people inhabit most of the more than 13,000 islands. The country is becoming a significant economic power in Southeast Asia. Indonesia is the largest Muslim country in the world. Java, its largest island, is the most densely populated area. The country's diversity is its strength. However, as only an estimated 16 million inhabitants speak bahasa Indonesia as the first language, communication problems endure. Although burdened with large debts, Indonesia has been able to service the debts better than most developing nations. This has given it high credibility and, with increasing frequency, creditor nations compete to provide Indonesia loans with the most the most favorable financial terms. Recent rising prices of petroleum crude has further improved Indonesia's economic status. It maintains a policy of stable oil prices that it promotes in OPEC, of which it is an influential member. As a result, Indonesia is becoming increasingly attractive to foreign investors. The South East Consortium for International Development (SECID) is made up of 34 universities in the southeastern US and Indonesian partners Lembaga Afiliasi Penelitian dan Industri (LAPI) of the Institute of Technology in Bandung, West Java. SECID bid successfully against international competition to develop new academic programs and campus for the Sriwijaya University UNSRI) in Palembang, South Sumara. Funding for the project was provided by the government of Indonesia through a loan from the Asian Development Bank (ADB). There are 47 public universities

Jan 1, 1991

By Elliott A, Kingsnorth D. J

The development of a large high grade spodumene orebody, in excess of 30M tonnes containing at least 7M tonnes at 4.0% Li20, by Lithium Australia Ltd at Greenbushes, Western Australia is significantly increasing the world consumption of lithium minerals. The availability of two low cost sources of lithium, spodumene concentrates (7.5% Li20) and glass grade spodumene (4.8% Li20) has been welcomed by the ceramic and glass industries as it assists them to lower their raw material costs at a time when they are facing severe competition from alternative materials. While there is no shortage of lithium reserves in the world, there has been a shortage of high quality lithium minerals. The Lithium Australia development has filled this need. The favourable factors of high grade, low impurities, open cut mining and existing infrastructure make this an ideal low cost source for a long term downstream lithium industry. The Lithium Australia mine development has filled the need for a reliable long term supply of lithium minerals. The long term viability of this resource is ensured by the unique combination of the following key attributes of the development : High grade reserves of 7.OM tonnes of 4.0% Li20 within 130 metres of the surface, contained within a total proven reserve of 30M tonnes of 2.8 % Li20. Open pit mining with stripping ratio of less than 2.5:1 waste:ore. Low impurities levels, particularly in those elements, that have a detrimental effect on the colour of glass/ceramics i.e. iron, manganese, titanium and chromium. An existing mine infrastructure that includes an adequate water supply for all foreseeable processing requirements. A sophisticated spodumene concentrator utilizing statistical process control to produce a consistently high grade product with minimal impurities. A technically qualified stable workforce fully acquainted with spodumene processing techniques. Greenbushes high grade concentrates have found ready acceptance in the specialty ceramic and glass industries during the past four years. The consistency and high grade/low impurity level of the product has enabled its use in the production of television tubes, oven to table ware, glass fibres, specialty glasses and ceramic glazes.

Jan 1, 1989

By K. Takahashi

Generally speaking, wastewater coming from the metallurgical process for recovering precious metal contains precious metals such as gold (Au), platinum (Pt), palladium (Pd), Silver (Ag), etc., which concentration is about 10 mg/L. In addition, there are other metals such as copper (Cu), iron (Fe), which concentration varies from several mg/L to more than 10,000 mg/L. It should be noted that the concentration of metals in wastewater is relatively high, considering the fact that these metals of similar concentration can be found in ores. However, most of these valuable metals are not treated, due to the high processing cost and technical problems. Within this frame, the authors put forward a new process that includes neutralization/reduction, precipitation and fusion. The idea is to recover and recycle Au, Ag, and Pd metals as well as protecting the environment by saving the resources. It was found that this new process was able to recover more than 90% of Au, Ag and Pd.

Jan 1, 2014

By J. M. Ortiz

This paper shows the usefulness of geostatistical conditional simulation combined with the quantification of sampling errors obtained from the analyses of fundamental errors ? validated from duplicate data ? to assess the relevance of the quality and quantity of the information, for short-term mine planning purposes. Traditional blast-hole drilling equipment has been designed for efficient drilling, but not for obtaining high-quality samples. Furthermore, blast-hole sampling interferes with production, and thus usually produces poor-quality results. These results are the basis of short-term plans, where the grades of selective mining units are estimated and used for distinguishing between ore and waste. Under these conditions, misclassification (ore blocks sent to the waste dump and waste blocks processed at the plant) is inevitable, leading to significant hidden losses that can amount to millions of dollars per annum. Reverse circulation drilling with the latest automated sampling technology improves significantly the quality of the information used for short-term planning, and thus reduces misclassification, improving the financial returns of the operation. In this paper, we present the general methodology for assessing the effect of poor blast-hole sampling, as compared to advanced reverse circulation drilling grids at several spacings, in order to arrive at the most appropriate grid for short-term planning. This plan can be prepared well in advance using several additional variables that are usually not available when the plan is based on blast-hole samples. Furthermore, blending options can be analysed in order to optimize plant recovery, minimize the use of sulphuric acid, etc. Three case studies are presented, namely a typical porphyry copper deposit, an exotic oxide copper deposit, and a complex gold deposit, where mineralization is controlled by structures and lithology. This paper shows that in all cases, advanced reverse circulation drilling grids provide good-quality information that, coupled with the use of geostatistics for short-term mine planning, significantly improve the financial returns of the operation.

Jan 1, 2014

By Trevor Yeomans, David Yaschyshyn

"Placer Dome (CLA) operates the 90-year-old Dome Mine, in South Porcupine, Ontario.The milling operation currently processes 5 million tons of ore per year, from both the underground and Open pit mining operations, producing 320 000 ounces. The milling process is conventional crushing and grinding, with gold recovery by gravity followed by leach/CIP.Cyanide tailings are impounded in a large (325 ha) tailings area where cyanide is allowed to degrade naturally. Effluent is discharged seasonally during the summer and early fall months to maintain site water balance. Pond water is reclaimed for sole use within the mill process.In 1995, an Effluent Treatment Plant (ETP) was constructed for the purpose of removing dissolved metals and suspended solids. In 1997, an INCO S02/Air cyanide destruction module was added.During this time period, the treated effluent often failed toxicity tests required by the Ontario MISA Regulation, even though effluent chemical parameters were below permit limits. Two studies identified ammonia as the toxicant to Rainbow Trout, and free copper as the toxicant to Daphnia magna.From a literature study, and contacts within the Ontario Mining Association, the use of chelation as a final end of pipe treatment step to render any remaining free copper and metal fractions biologically unavailable was considered. Lab and plant scale tests followed.During the 1999 ETP operating season, the addition of the chelant EDTA (ethylene-diamine-tetraacetic-acid) commenced. To date discharged effluent has passed all toxicity tests.The paper will review the effluent treatment history, current effluent treatment plant operation, and detail the use of EDTA for successful toxicity control.History of Tailings Deposition, and Effluent Treatment From 1910 to 1995Over it’s ninety years of operation, the Dome Mine milling circuit has changed from the original 1910 stamp-mill mercury plant, to today’s modem 14 000 ton per day automated gravity and Carbon in Pulp based plant.By the 19803, a modern mill was operating on mainly underground mined ore. The plant was operating at some 3 800 tons per day, using fairly conventional processing routes.The number 4 tailings dam was being used for tailing’s deposition.All effluent treatment was by natural degradation of cyanide. Discharge was from decanting type structures during the summer months only, maximizing the use of natural degradation no tailings effluent was recycled for Mill use."

Jan 1, 2001

By M. P. Valoski

Mine fires and/or explosions continue to occur. While these are unusual events, they comprise emergency situations. Whenever one of these events occurs, the Mine Safety and Health Administration (MSHA) responds with specially trained teams, mine fire experts, sophisticated scientific instrumentation, and trained instrument operators. In order to analyze mine air samples on-site, because time is of the essence, MSHA has a Mobile Gas Laboratory. The laboratory, which is stored near Pittsburgh, is totally self-contained. Sending air samples to a laboratory would take too long. Mine fire experts need the results of the latest analyses as soon as they are finished. The mobile laboratory is housed in the box of a diesel truck. Benches line both sides of the laboratory. Gas chromatographs are mounted on the benches. There is sufficient bench space for multiple bench top gas chromatographs. These instruments and their controllers are shock and vibration isolated to protect them during transit. The mobile laboratory can operate using on board diesel generators or line power. An uninterrupted power supply (UPS) supplies power to the instruments while switching from generator to line power or visa versa. Therefore, analysis of samples can proceed without interruption if a power failure would occur. In the rear of the mobile laboratory are racks that hold compressed gas cylinders. These cylinders contain carrier gas and compressed air. An air compressor is housed under the laboratory to operate the gas chromatograph actuators. Within several hours after arriving at a mine the instruments have stabilized and have been calibrated. The mobile laboratory is ready to begin analyzing air samples. The mobile laboratory has proved itself at many mine fires and explosions since its purchase.

Jan 1, 2009

By R. Karl Zipf

The sudden, violent collapse of large areas of room-and-pillar mines poses a special hazard to miners and mine operators. This type of failure, termed a "Cascading Pillar Failure" (CPF), occurs when one pillar in a mine layout fails transfering its load to neighboring pillars causing them to fail, and so forth. Recent examples of this kind of failure in coal, metal and nonmetal mines in the U.S. are documented. Mining engineers can limit the danger posed by these failures through improved mine design practices. Whether failure occurs in a slow, nonviolent manner or in a rapid, violent manner is governed by the local mine stiffness stability criterion. This stability criterion is used as the basis for three design approaches to control cascading pillar failure in room-and-pillar mines, namely, the containment approach, the prevention approach, and the full extraction mining approach. These design approaches are illustrated with practical examples for coal mining.

Jan 1, 1996

By Robert D. Saltsman

Two modes of seal application were identified, and promising state-of-the-art seals of both types -shaft and drum -were selected for initial rating by non-destructive testing. Only one shaft seal survived the initial test, and a search was made for other candidate seals including new seals. One new type of seal was found that gave promising enough operation, as both a shaft and drum seal, to be recommended for installation in prototype wet-head machines.

Jan 1, 1975

By E. H. Denny

The presence in the Cripple Creek district, Colo., of irrespirable gas or gases, generally known to consist mainly of nitrogen and carbon dioxide, has been recognized by members of the mining industry in that region almost since underground mining was begun there; the occurrence, origin, and possible control of these gases have been discussed in several articles cited at various places in this report. Similar gases have also been studied in other metal-mining districts, as later discussed. In March, 1925, there were two fatalities from rock-strata gases in the shaft of the Index mine, near Cripple Creek. Two men repairing the bell or signal line preparatory to reopening the shaft were lowered into irrespirable gases and died. Their bodies were recovered by rescue crews from the United States Bureau of Mines and .the Portland mine, Victor, Colo. These crews found it necessary to use oxygen breathing apparatus. In October of the same year a miner was trapped on the 6 level of the Midget mine by an influx of gases that filled the shaft to a point above that where he was working. Oxygen breathing apparatus was again used by Bureau of Mines employees, who were in the vicinity, and the man was brought out in time to save his life. These two fatalities and one near fatality seemed to show that additional investigation of the gases and methods of control might be warranted. Accordingly, field and laboratory studies were begun by the authors of this report after a visit to the district by M. van Siclen, then engineer in charge, mining research division, Bureau of Mines, and after conferences with the Mine Owners' Association of Cripple Creek and with J. T. Joyce, metal-mine commissioner of the State of Colorado. The mine operators of the Cripple Creek district and the State mine commissioner's office gave whole-hearted cooperation in this work.

Jan 1, 1930

By Sunil Koppalkar, A. R. Laplante

"A Pilot Plant was installed in one of the grinding circuits of the Dome Mill, Ontario, Canada. Tests were conducted on a KCCD12 Knelson Concentrator to systematically analyze the effect of operating variables on the performance. The main objective of this test work was to explore the effect of very coarse (6 mm) feed size on GRG recovery and performance of the Knelson concentrator. Preliminary results have shown that coarse feed size is deleterious to maximizing recovery. Size-by-size GRG recoveries have shown an unusual trend in the sense that recoveries do not decrease monotonically with decreasing gold particle size. Similar trend observed in one other full-scale unit has been compared. The observed trend is probably linked to the feed size distribution and top size.INTRODUCTIONKnelson Concentrators are the most widely used semi-continues centrifuge gravity separation units for the recovery of gold and platinum group minerals (Xiao and Laplante 2004). The main advantages over the competing centrifugal gravity units are their design, operating simplicity and good separation efficiency that make them the most common choice for gravity circuit. Despite some characterization at bench scale and a limited characterization at full scale, there is a lack of a comprehensive study of impact of operating variables on efficiency that reflects realistic full scale operating practice. GRG characterization studies, at bench scale, on these units provide information about the occurrence of gold in ore samples but fail to provide adequate information about the effect of operating variables for full-scale units. It is well known fact that such work is difficult to undertake on full-scale units owing to the difficulties involved in sampling and systematic variation of operating parameters. To tackle these problems, a pilot facility consisting of a 12-in CD Knelson Concentrator, a feed screen and tailing pump was installed in one of the grinding circuits of Dome Mill. This paper describes the work carried out and the results.Porcupine Joint Venture (PJV)Porcupine Joint Venture was formed in 2002 between Placer Dome Inc. and Kinross Gold Corporation. The JV utilizes the milling capacity of the Dome Mill to process ore from Placer Dome and Kinross mines. The Dome Mill circuit has gravity concentration, cyanidation and CIP circuits to recover gold. Gravity recovery has been used at Dome Mill since inception to recover gold: first by using conventional jigs, which were eventually replaced by two Knelson Concentrators in 1993, one in each of the grinding circuits. Three more Knelsons joined the circuit in 2002 to improve gravity recovery. An Acacia Intensive Leach Reactor was also added in 2002 to process gold concentrates replacing shaking tables (Chong et al 2004)."

Jan 1, 2007

By J. L. Thornton

Introduction The importance of coal in our economy is well established, but it may not .be so generally realized how important a part it plays in our daily life. Select a product - any product - and, if it is made in America, bituminous coal has touched it first. Everywhere we will find coal, derivatives of coal, or functions made possible by coal. Apart from the well known major uses of coal for domestic purposes, coking, utilities, railways, and manufacture of steel and cement, there are over 200,000 products derived from coal, from lipstick colours to nylon products and perfumes. An item of interest is the recent action of the Canadian Government in voting $90,000 for development of coal deposits in Yukon Territory to make coal available to the settlers in that area. The value of this move, in case of some emergency, is very evident. Coal in its several stages of formation as peat, lignite, sub-bituminous, bituminous, semi-bituminous, semi-anthracite, and anthracite, has been used for centuries. Coal, as such, was not very well known to the ancients. First reference to "magic stone', or coal, was in 371 BC by Theophrastus, a pupil of Aristotle. This substance was said to burn like wood coal or charcoal and was used by the smiths. The first record we have in modern times was in 852 AD, when sea coal was gathered by the cowled monks of Durham, in Britain, and even at that time a major problem was transportation. Our first record of coal in this continent was near Richmond, Virginia, in 1700. Commercial mining was not under way, however, until 1750. The anthracite fields (presumably in Pennsylvania) were opened in 1793. Even so, there was no extensive mining until about the year 1820. The famous Pocahontas coalfields were opened in 1883. The earliest record of coal mining in Canada is about 1746.

Jan 1, 1950

By M. Rancourt, J. Levay, D. K. Murphy

INTRODUCTION The LG-2 project is one element of the La Grande Complex, an integrated development of hydro-electric potential being constructed in north-western Quebec by the James Bay Energy Corporation. The project is located on the La Grande River about 65 miles east of Fort George on the James Bay coast and 600 miles north of Montreal. It comprises a 525 foot high dam, 81,000 feet of dykes, spillway and river diversion works and a 16 unit underground powerhouse that will have an installed capacity of 5,328 MW. The power installations at LG-2 represent approximately half of the total potential for the complex. When completed in 1982, LG-2 will rank as the largest underground powerhouse in the world. Studies and site explorations for the project were begun in 1971, construction commenced in 1973 and the roll date for the first machine is scheduled for February, 1980. GENERAL ARRANGEMENT OF POWER INSTALLATIONS As shown in Figure 1, the power installations are located on the south bank of the river about 4 miles downstream from the main dam. The general arrangement of the complex is presented in Figures 2 and 3. The intake structure consists of 2 groups of 8 gated intakes separated by a central service area. Sixteen 26 foot diameter in-

Jan 1, 1976

Mine waste and mine reclamation are topics of major interest to the mining industry, the government and the general public. This publication and its companion volume are the proceedings of a conference held in Pittsburgh, April 19-21, 1988. There were nine sessions (50 papers) that dealt with the geochemistry, hydrology and problems of mine waste and mine water, especially acid mine drainage. These comprise Volume 1. The nine sessions (43 papers) that dealt with reclamation and restoration of disturbed lands, as well as related policy issues, are included in volume 2. Volume 2 also contains the ten papers that pertained to control of subsidence and mine fires at abandoned mines. Poster session presentations are, in general, represented by abstracts; these have been placed in the back of both volumes.

Jan 1, 1988

By Patrick E. Durnal

The Richmond-San Rafael Bridge was built in the early 50s' and was first opened to traffic on August 31, 1956. Among California's longest steel bridges, it spans more than 21,000 feet across the northern portion of San Francisco Bay. It is one of six toll bridges currently undergoing seismic retrofit in the Bay area. Current retrofit criteria require the structure not to collapse in a Magnitude 8.3 earthquake lasting 45 seconds on the San Andreas Fault. The earthquake epicenter is 10 miles to the west of the Bridge, near the mouth of San Francisco Bay. Another major fault is the Hayward Fault, with a potential of a 7.5 magnitude earthquake. It is only 4 miles east of the eastern end of the bridge. The retrofit criterion is that the structure survives these earthquakes without collapse or loss of life, and that they are capable of repair within a period of one year. Therefore an energy absorbing, ductility and nominal resistance based approach to the retrofit design have been adopted for the retrofit of this bridge. Foundation Retrofit The foundation retrofits were designed to satisfy of drift criteria of 6 inches at the base of the footings, and to keep the existing H-piles from experiencing unacceptable levels of permanent soil displacement and /or structural rupture. Full-scale structural lateral load testing of BP14x89 piling, to rupture, has helped to determine the drift criteria. However recent non-linear analytical results, have led to a redesign, which may allow for 12 inches of drift. The as-built analysis of the Micropile piers determined that those piers would not exceed the 6-inch drift criteria so lateral resisting shear piles were not needed at those piers.

Jan 1, 1998

By Frank Haehnig, Kjell-Åke Averstad, Johannes Glückert

"AbstractThe Söderströmstunneln is part of the Citybanan project that is currently under construction in the centre of Stockholm. Main part of the lot Söderströmstunneln is a 300m long immersed tunnel connecting the inner-city islands Södermalm and Riddarholmen. It consists of three tunnel elements that have been immersed in summer 2013. Since the solid bedrock is descending in that area to more then 40m depth, the tunnel elements have been placed and are permanently supported on four pile groups that have been constructed in advance. The common Swedish system of steel core piles has been used to built the pile groups. Drilling and installation of the steel cores piles in free water depth of up to 20m had to be done from a pontoon. The steel core piles are connected with underwater concrete pile caps.IntroductionCitybanan is a new 6km long double track railway tunnel running beneath central Stockholm including two new underground stations Odenplan and Stockholm City. When completed in 2017 commuter trains will have their own tracks through Stockholm, whereas the remaining railway traffic will continue to use the exisiting two tracks (see Fig. 1). This will double the capacity of the railway traffic through Stockholm. The Swedish transport administration Trafikverket is the client for this project. The design and built contract is carried out by the German contractor Züblin Spezialtiefbau GmbH together with their Swedish subsidiary Züblin Scandinavia AS.As the new Citybanan tunnel is in large parts situated below the bedrock level, it can be executed as rocktunnel in the common drill and blast method. Between the two inner-city islands Södermalm and Riddarholmen the tunnel is crossing the Söderström, an arm of the lake Mälaren. Here the bedrock is descending to a deep valley with more then 40m depth. To connect the rock tunnels between these islands a 300m long immersed concrete tunnel supported on pile foundations is currently under construction."

Jan 1, 2014

By R. L. Brown

This report, summarizing the Bureau of Mines research and technologic work on coal and coal products for the period July 1, 1950, to July 1, 1951, is based largely on publications issued during the year. The sixteenth in an annual series, it gives footnote references to publications giving further details of the research and technologic work described, except in a few cases where research data presented herein has not been published previously. During the year, the national fuels situation was generally one of plentiful supply.3/ Mineral-fuel resources appeared adequate for several hundred years at reasonably increasing rates of supply. Coal-production capacity was in excess of demand; petroleum supplies were adequate; and natural gas use was limited only by pipeline capacity. However, it was pointed out that a world war would drastically change this situation of relative plenty, particularly with regard to supplies of petroleum and its products. Conversion to the use of coal on a large scale would be required, and improved methods of mining and of processing and using coal in solid or fluidized form or converted to liquid fuels could materially contribute to our national safety.

Jan 1, 1952

By Harry Siewert

"The commissioning of the 4th concentrator (C4) at Freeport Indonesia in early 1998 increased total mill throughput from 130k to 230k tonnes per day. The C4 flowsheet consists of a single 38 ft diameter SAG mill, four 24 ft diameter ball mills followed by four banks of 4,500 ft3 WEMCO flotation cells.The design of the C4 rougher flotation circuit was based on the expectation that the copper and gold recoveries achieved with the 4500 ft3 flotation cells would be equivalent to or better than that achieved with the 3,000 ft3 flotation cells in the 3rd concentrator (C3) rougher circuit. This assumption was due to the fact that the C4 flotation feed size would be less than 15% +212 microns compared to the C3 rougher flotation feed size of less than 23% +212 microns. By mid 1998 it had become apparent that the C4 rougher flotation copper and gold recoveries were below those predicted.In order to determine the cause of the lower recoveries, stage by stage rougher flotation surveys were performed in all four concentrators. The results of the surveys showed that the C4 rougher flotation circuit had a lower recovery of +200 micron material than that achieved in the C 1, C2 and C3 concentrators. Through mineralogical analysis, it was determined that a majority of the copper contained in the +200 micron fractions was liberated and recoverable. This paper describes the steps taken to increase coarse particle recovery, overall plant recovery and the results achieved."

Jan 1, 2001

By G. Noce

The ever more present necessity for greater precision in foundation structures on vertical piles subject to horizontal forces applied to the heads, in the light of of the latest knowledge about the elastic-plastic behaviour of the soil has led to the use of numerical calculation for the formulation of a general resolution method for the problem. The calculation method that will be set out, applicable to piles with inertia moments variable discreetly along their axes is especially useful when studying steel structures for medium and large tonnage vessels for which the metal piles are often constructed for the assembly of section of equal external diameter but different thickness and therefore different inertia moments. Two examples are given of constructions whose foundations have been projected with these calculation tools, one in the railway sector (foundation pile for the river Nera viaduct - Italy) important for the limitation of horizontal relative deck displacement, the other maritime (Dolphins of the petroleum pier of the port of Bandar Abbas - Iran).

Jan 1, 1989

By Don A. Toth

Until recently, the fire protection systems used to protect mining equipment were based on generically designed, off the- shelf concepts. These systems were reliant on single agent approaches and were generally comprised of a series of small twenty or thirty pound chemical canisters that would discharge their contents when triggered by thermal detection means. As the equipment grew in capacity, the logic used to increase the protection was to add more chemical canisters to the system. Hydraulic excavators and large-scale mining trucks grew dramatically in size into the 1990?s and beyond; with this growth came the increase in major losses due to fire. This was evidenced throughout this period, and continues to be of great concern today. During this presentation you will learn of the significant changes that have come about as a result of this history. Today, dual-agent products, infrared detection and unit-specific, engineered systems are the primary phrases used when discussing how to best protect this equipment from fire loss. This session is a must for anybody looking to optimally protect their equipment assets and for those looking to renew and/or secure new insurance for high value equipment in the future.

Apr 1, 2005

By R. I. C. Manning

The Old Dominion Co, at Globe, Ariz., like the: Phelps Dodge Corporation with which it is closely allied, considers safety a major operating problem. Safety is fostered by this company in consideration of both the humanitarian and economic aspects; the officials, take pride in promoting the welfare of employees, and the management has found that the safest way is the most eco¬nomical and that unless an organization is operated economically it can not continue to exist successfully. In planning and operating any safety, organization, terry things must be taken into consideration because an Enterprise can not be operated solely for safety any more than it can for any other single part of the operations. All work must be planned and executed for the common interest.

Jan 1, 1931