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By Christy Z. Lueders

Introduction More and more women engineers are joining the traditionally male mining industry. Are they successful? Do they encounter special problems? How do men in mining respond? How can the mining industry effectively use its female resources? What contributes to the success of a woman in mining? What can male engineers do to ease the entry of female professionals into the workforce? An STM survey conducted last spring provided some answers to these questions. All BS graduates in mining, mineral engineering, and extractive metallurgy from 1960-1979 were surveyed. Nearly 60% of the female graduates, from 17 universities, completed questionnaires. The women were asked why they chose mining, how they relate to predominantly male co-workers, what job skills they have gained, and what areas of work they most enjoy. They were also asked how problems of a two-career family are solved. Data were gathered on salaries, titles, specialties, and products handled. Respondents, assured of confidentiality, are identified only by title. Many male mining executives were also questioned for their advice to women in mining. Profile of the Survey Participant The "typical" female mining engineer works with coal, is employed by an operating company, feels she works very hard to prove her abilities, does not want to be treated as an anomaly, and someday wants to be an independent consultant. Of the respondents, 44% listed coal as the most familiar product, 12% said copper, and the rest listed products from industrial chemicals to oil. Titles varied widely but women managers are rarely found. However, the majority of the survey population graduated after 1976 and thus lacks substantial experience. Of 102 female graduates, only 25 graduated before 1977. Since then, there has been a steady increase. The American Association of Engineering Societies reported that in 1980 more than 100 degrees were awarded to women in minerals engineering. Education Highly Valued Twenty-two percent of the women surveyed had graduate degrees, 38% planned further education, and 12% listed a PhD as their goal. The majority of graduate degrees are in technical fields. There were only two MBAs. Five women intended to pursue law degrees, and one woman, with a mining engineering degree and an MBA, is a part-time law student. Along with advanced education, the women agree that production experience is needed for career advancement. However, only 28% of the women have worked in production. Many women, especially younger grads, commented that these are the toughest jobs to get. This is a universal complaint, from males as well as females, though women seem to encounter more opposition. Several women mentioned they were small or slight of build and managers tended to shy away from hiring them for production jobs. Two-Career Marriages The most difficult problem for two-career couples is relocation. Whose career takes priority? Fifty percent of the women said transfers or offers would be examined on a case-by-case basis, weighing pros and cons for both parties. The husband's career took priority with 47% of the women; their own careers, with 3%. These statistics conflict with comments from two employee relations managers. Both said most female engineers they've encountered are married to men who follow their wives' careers. Seventy per cent of the married respondents said their husbands were also engineers. Four said their husbands were engineers at the same company. Some male and female engineers met on the job; others joined the company as a "package deal." Both partners being engineers can ease relocation problems, since an area or company offering one spouse a job can often provide a spot for the other. A company may benefit by getting two new hires for the relocation costs of one. Most companies contacted have policies that allow married couples to work at the same division, but discouraged them from working in the same department. With 40% of today's marriages ending in divorce, one risk is that one or both parties may quit. One personnel executive said there were several couples, each spouse in a different discipline, who were work¬ing out very well at his division. However, he recognized the potential for problems if, for instance, one gets promoted and the other doesn't, or salary increases are unequal. The personnel executive said he has actively recruited married couples, and would again, were each person competent.

Jan 10, 1981

By P. P. Andrieux

The recovery of the Zone G crown pillar, located between the bottom of the open pit and the top of the underground workings at the Raglan Katinniq Mine in Nunavik, started in the summer of 2008 and should be completed by the end of 2009. This article describes the rock mechanics-based approach implemented to design the recovery of this valuable block of ore. The stereophotography-based ShapeMetriX3D technique was first used to provide a comprehensive assessment of the various joint sets that comprised the pillar. Then, the statistical distributions obtained for the dip, dip direction, spacing and persistence of these sets were used in conjunction with the geometry of the large-scale faults present in the area to build and run a series of explicit rigid numerical models. Each of these models had a slightly different jointing geometry, randomly constructed from these statistical distributions. Incorporating in a properly formulated numerical model the variability of some of the input parameters has allowed the engineering team to assess in a rational and reliable manner the likelihood of success of the proposed mining method and sequence.

May 1, 2009

By Higgins RJ

Environmental investigations have been undertaken by Ok Tedi Mining Limited (OTML) since 1981 when the Ok Tedi Environmental Study was commenced. Environmental monit- oring and management programmes were implemented in 1983. The programmes included water quality monitoring, river flow and sediment monitoring, surveillance of aquatic biological communities and a health and nutrition survey of the local people. These original programmes have continued, and additional programmes of work have been developed and revised to reflect changing operations and the need to focus investigations on specific areas and issues of concern. In April 1990, following the establishment by the Government of Papua New Guinea (PNG) of environmental management criteria for the Fly River system, compliance monitoring programs were introduced. Details of the compliance and additional monitoring programmes undertaken by OTML throughout the Ok Tedi and Fly catchments, including programmes of investigation in the Fly River estuary, Gulf of Papua and Torres Strait, are presented.

Jan 1, 1991

Jan 1, 1967

By Robert Thomas

DURING the past 20 years the advantages of reinforced concrete as a substitute for timbering in so-called permanent mine openings have been fully recognized, and its use has become almost general practice in the larger mines. The term "permanent mine openings" is used advisedly and is assumed to embrace such openings as ventilation shafts, material shafts and main hoisting shafts, with their adjacent stations, ore pockets, etc. In the concreting of such openings, the actual cost as compared with that of timbering has been of secondary consideration, the support of large openings, elimination of fire hazards, and prevention of inter-ruptions to production being the primary objectives. The ultimate economy, however, of lining such openings with concrete when they are to remain in use during the entire life of the mine, and especially when they are in bad ground, will seldom be questioned. During this 20-year period there have appeared in engineering publi-cations a number of interesting articles on the use of concrete in mines, nearly always describing some specific project of major proportions, such as the concreting of ore pockets, large stations or main hoisting shafts. Such articles are unquestionably of interest, since the projects require considerable engineering thought, not only in the method of excavating large openings, but in their engineering design as well. Concreting of main hoisting shafts, particularly when this is done with the least possible interruption to production, provides some interesting problems. The concreting of haulage drifts of the dimensions commonly found in mines, on the other hand, soon develops into a routine operation, there-fore it is with some hesitancy that the author attempts to prepare an article on this subject. The writer can recall only one article on the concreting of mine haulageways, although several articles have been written concerning the concreting of tunnels considerably larger in dimensions than those required in general mine practice.

Jan 1, 1936

By Rainer Kahrger

During the last decade, advances were made in solvent extraction/electrowinning (SX/EW) technologies. Combined with heap leaching, these technologies made it viable to exploit large, low-grade oxide copper deposits. The El Abra Mine is a good example for such a deposit. The deposit is situated in northern Chile at an elevation of about 4,000 m (14,000ft), 70 km (45 miles) north of Calama. Codelco sold 51% of the El Abra to Cyprus Minerals in June 1994, with Codelco retaining the balance. In 1993, Cyprus and the engineer on the project began discussions withinternational companies regarding the materials-handling system requiredfor the project. These early discussions were considered critical for this fast-track project.

Jan 1, 1996

Standard petrographic profiles for many Permian seams from New South Wales and Queensland have been drawn up. The standard profiles of seams of the same age and from one or more coalfields were used to compile an idealized or type seam sequence for those coals in which more than half the seam profiles were similar to one another. A marked similarity existed between at least 7 of the 10 type seam sequences formed.The configurations of the vitrite-plus-clarite contents of the plies of 95 per cent of the seams could be formed from different arrangements of 3 basic sequences. These were...

Jan 1, 1970

By R. Schuhmann

Jan 1, 1965

By Paul Krivokuca

Outline Quinsam Coal Mine ?? Location ?? Mine History ?? Safety ?? Production ?? Hiring 4S Mine ?? Depillaring design ?? Structural mapping, Risk assessment ?? Rock Bolt Design Selection ?? Training

May 1, 2008

By Jeremy Morris

The city of Indianapolis has more than 25,000 homes currently on septic systems. Many of these systems do not function well because of their age and surrounding soil conditions. As Indianapolis has worked to eliminate septic systems and install sanitary sewers in large unsewered areas on the north-west side, capacity of the existing Belmont North Interceptor (BNI) became a concern. The BNI system currently services an area of approximately 80 km2 (31 sq miles) located within the northwest quadrant of the city (Fig. 1). Monitoring of the existing interceptor indicated portions of the sys-tem flowing half- to two-thirds full during dry weather conditions and surcharging during some wet weather conditions. Further analysis of the BNI based on growth projections coupled with increased sewershed yield resulting from the city?s septic tank elimination program (STEP) indicated dry-weather flows could potentially triple over the next 20 years. Based on these modeling results and current wet weather capacity issues, the city determined further STEP projects could not be performed within the BNI service area until

Jan 1, 2011

By Hart G. H

In tectonically disturbed zones within coal seams, decreases in the amount of kaolinite in the cellular structure of inertiniterich coal are accompanied by increasing kaolinite contents in fractures within the coal and/or rocks of immediately overlying horizons. This is due to fracturing of the inertinite microstructure by tectonic disturbance and remobilization and redistribution of free, fine-grained material (kaolinite and/or inertodetrinite.) Ascending waters are believed to transport the kaolinite in suspension, and redeposit it in the fractures and pores in the overlying horizons. This removal of material from the inertinite-rich coal leads to an increase in porosity (higher free gas storage), a presumed reduction in coal strength and an apparent increased proneness to instantaneous outbursts of coal and gas.

Jan 1, 1983

By Bruce Vandenberg, Andy Bartfay-Szabo, Steve Conway

Recent advances in solid-state, field portable, fast framing video camera systems and PC based frame capture hardware now allow blast imaging up to 500 frames per second. Up to 8 seconds of data can be stored directly into the unit, downloaded to a PC or archived to a standard VCR without data compression. Since no film processing is involved, motion analysis can be performed instantly and on-site within a few minutes. This paper will describe the design features and applications of the SVClOOO system and compare these with the analogous aspects of film based cameras.

Jan 1, 1995

By Kazunori Matsushita, Frank Vespi, Emi Walder, Mitsuo Nozu

During the runway expansion project at the Fort Lauderdale-Hollywood International Airport in Florida (FLL project), therewere complicated geotechnical issues with a number of cavities in the limestone-loose sand mixed ground thatexisted in many areas below the existing ground. Collapsing the cavities and compacting the runway foundation to secure the take-off and landing of aircrafts was a necessary requirement for the project. The Mammoth Vibro-Tamper (MVT) which produces less vibration and noise level, was proposed and accepted as the alternative to the originally specified Deep Dynamic Compaction (DDC) for the runway with its length of 1.5 miles and area of 570,000 square yards. In this report, the shallow compaction effect and reduced ground vibration with the MVT are presented in comparison with the DDC which was utilized on the same project in a different area of the airport. INTRODUCTION MVT was developed by Fudo Tetra Corporation in the 1960’s and has been widely used in Japan (more than 14,400,000 square yards). For example, at the Kansai International airport, a large area including aprons was compacted with the MVT. It is capable of compacting up to approximately 5m in depth by using a heavy steel plate (3m x 3m) and a strong vibrator motor (V-180, 10Hz) on top of the steel thick plate with specified time duration. We were involved in densification work with the MVT at the Fort Lauderdale Airport Project (Figure 1) from June, 2012 to February, 2014. Deep Dynamic Compaction (DDC) was originally specified as the compaction method to secure the relative density over 70% in every 2,000 square yards grids, however, we proposed the application of MVT to reduce the vibration risk and it was accepted as the alternative (Figure 2). The compaction work was completed in February 2014, without causing any delay in regard to the residual settlement due to the high embankment (H=60ft=18m).

Jan 1, 2018

By Enrique Castells

La extracción del mineral es el método más habitual para la explotación minera y se realiza a través de rampas, galerías, y túneles que permitan el acceso hasta la zona de minado. Sin embargo, cuando se da una excesiva profundizaciión del terreno, se emplea el método de pique vertical ya que logra el acceso de los operarios a las zonas más profundas de un modo más rentable y rápido a través de la extracción del mineral por izado de vagones o skip hasta el de nivel de superficie o intermedio. Por ello, es común que las minas replanteen la sustitución de su sistema de extracción habitual por el de izado por piques. En este sentido, el presente trabajo desarrolla la aplicación de los piques verticales en los sondeos de exploracion de la mina Hullera Vasco Leonesa. La primera parte del proyecto describe la ejecución de dos piques verticales (Aurelio y Emilio del Valle), y la segunda, en la ejecución de más de 17.000 m de galerías y obras de infraestructura de diversa índole.

Sep 13, 2001

By Olga Frank-Kamenetskaya

The experimental results of study of atmospheric corrosion processes on Saint-Petersburg bronze monuments surface, received in situ and by means of simulating experiments, have been discussed. Influence of the time factor on corrosion film (patina) mineral composition has been analyzed. Direct dependence between patina mineral composition and environmental conditions has been proved. The sequence of patina phases crystallization has been established. Effect of the chemical composition and heterogeneity of artistic bronze and also monument surface structure on the rate of corrosion process has been regarded. The time variations of mass of the crystallized in the hydrochloric acid vapor phases have been investigated. The kinetic laws of their development at the initial stage of formation, indicating simple (non chain) reactions, have been revealed.

Jan 1, 2006

By Jai Ghosh, Aprad E. Torma, Roger Guay

The catalytic effect of ferrous ion in the industrial biohydrometallurgical heap and dump leaching processes is explained. During the bacterial leaching of metal sulfides, ferric ion will partly be hydrolyzed and a variety of sols, gels, amorphous and/ or crystalline mono- and polynuc- lear hydroxo- and sulfato complex species formed, especially by olation and aggregation reactions. There are many problems associated with these iron precipitates especially in the purification of leach solutions. The present study will discuss the iron precipitation reactions; gives kinetic and thermodynamic evaluations of the effect of temperature on pyrite and ferrous iron oxidation; and reports on the tolerance of heavy metal ion concentrations by Thiobacillus ferrooxidans.

Jan 1, 1989

Acoustic Emission Monitoring of Froth Flotation

Sep 13, 2010

By G. A. Calboreanu

One way of cost reduction is attained when using materials with improved erosion ? corrosion resistance. For many years hard irons successfully answered the Mining Operation needs however application ranges were limited due to the low chemical resistance of such alloys. Corrosion resistance of any hard iron increases when microscopically homogenizing chromium and generating passivation conditions throughout and between all metallographic phases. Chromium distribution of the new material called Max10 was analyzed with EDS ? energy dispersive spectroscopy. At critical depleted chromium carbide ? matrix interfaces chromium increased to 31.72% which is well within passivation levels. Generally the corrosion resistance of high chromium hard irons provided by Metal Casting Industry is limited to 0.5% sulfuric acid and 28 PPM ionic chlorides. Such restrains increased when using Max10 to 2.0% sulfuric acid and 100 PPM ionic chlorides. Max10 contains 35% carbide volume fraction, has excellent corrosion resistance within pH = 1.15 ? 13.6 while fracture toughness under plain - strain conditions and Mode I opening is KIC = 20 KSI.(inch)1/2. Wear rate was calculated with the pin-on-disk apparatus using a diamond indenter per ASTM G99 recommendation. After years of research, experimentation and implementation the Max10 castings were service installed in slurry pumps and mixing equipment. In some applications the life time of slurry pumps manufactured in Max10 tripled versus previously used materials.

Jan 1, 2012

Detailed mineralogical investigation of a tailing sample from the Juno plant circuit at Tennant Creek was carried out to determine the nature of the unrecovered bismuth and whether any possibility existed for improving bismuth recovery. The investigation showed that the Ibismuth was present in a complex mixture of Bi-Pb-Ou-Se-S minerals (termed "bismuthinite"), of which about 74 per cent was locked (mainly with magnetite) and 26 per cent was liberated (18 per cent in the minus 7 µm slime). The results suggested that attention should be directed to both finer grinding and improved flotation of slime "bismuthinite", and testwork carried out by Peko Mines N.L. on the basis of these recommendations led to a significant improvement in bismuth recovery.Detailed mineralogical investigation of two Juno concentrates was carried out to determine the nature of the selenium present and whether any possibility existed for improving the selenium grade. The investigation indicated that virtqally all the bismuth, selenium, and lead was present in "bismuthinite", which showed a composition range of 32-82 per cent Bi, 0-42 per cent Pb, 0-24 per cent Se, and 5-18 per cent S. Differences in the Bi/Se ratios of the two concentrates could be attributed to different average Bi/Se ratios of the constituent "bismuthinite", and the relatively low selenium grade of the "bismuthinite" precluded the possibility of obtaining a high grade selenium concentrate with high selenium recovery.However, differential flotation and/or low intensity magnetic separation to remove chakopyrite, and magnetite, the main diluents of the concentrate, could be expected to upgrade the selenium content byup to 80 per cent (relative) and .festwork carried out by Peko Mines N.L. on the basis of the recommendations of the mineralogical investigation confirmed that depression of chalcopyrite in the flotation circuit could produce significantly improved selenium grades.These investigations illustrate the application of mineralogy to the practical problems of improving plant performance. Mineralogy has an important role to play in providing quantitative data on which the metallurgist can evaluate plant performance and base a programme of metallurgical testwork, and early mineralogical investigation of feeds, concentrates, middlings, and tailings can lead to the avoidance of much abortive and expensive metallurgical testwork.

Jan 1, 1974

By M. Abdellatif

The production of a 40% Al-Ti alloy was successfully proven at the lab scale, using pure TiO2, aluminium, and lime. These tests were conducted in an induction furnace maintained at 1600?16250C. The introduction of rutile into the feed recipe resulted in an alloy containing between 0.35 and 1.10% Zr, depending on rutile to TiO2 ratio. DC arc production of the alloy was largely accomplished at 40 and then 200kW scale. These tests evaluated various metallurgical and operational factors including target slag composition, Ti-content in the alloy, co-feeding versus sequential, furnace bath depth, and rutile as part of the Ti containing feedstock. Overall, an alloy containing 24?33% Ti was consistently produced with co-feeding of the reactants and with lower taphole tapping. When rutile was added, the zirconium analysis in the alloy remained below 0.2%. The main impurity elements were iron, silicon, carbon, nitrogen, and oxygen.

Jan 1, 2009