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By K. J. Sollman

With an ongoing concern for safety and health in the workplace, NYCO® requested three medical evaluations be undertaken to study possible health hazards of wollastonite. Two of the evaluations were conducted by the National Institute of Occupational Safety and Health (NIOSH). One was in 1976 (Ref. 1), and the second in 1982 (Ref. 2). The aim of the two studies was to answer the following two questions: 1. Do wollastonite workers exhibit more respiratory abnormalities than workers not exposed to wollastonite? 2. Is there a relationship between prevalence of respiratory abnormalities and accumulated expo-sure time to wollastonite?

Jan 1, 1988

By J. W. Mahar, E. J. Cording

INTRODUCTION In exploration for rock tunnels, the geology should not only be described, but its effect on excavation and support assessed. It is not an easy task to correlate exploration results with support and excavation requirements, even when the exploration program is detailed and geologic conditions are relatively well known. Many of the significant geologic features are subtle and their effect is difficult to interpret from exploration results. However, in similar geologic settings, there are specific geologic features which will cause recurring support problems. Such features should be actively sought out when exploring in a given geologic setting. In blocky and seamy rock, the primary features controlling performance are the joints, shears, and shear zones. This paper describes the effect of such features on the formation and movement of rock wedges in tunnels driven in foliated metamorphic rocks in Washington, D. C. and New York City. In both areas the foliation commonly forms a N-S striking plane of weakness along which major shear zones, shears, and joints have formed. In addition, the structural history of the two areas has been similar, so that there are similarities in the orientation and character of the other major joint sets and shear zones in the rock mass. The observations were made in tunnels ranging from 10 to 70 ft in width and excavated at depths ranging from 80 to 800 ft. Most of the tunnels described were deep enough to be located in unweathered rock, or in rock only slightly weathered along joints and shears. Variations in the planarity, filling, spacing, and attitude of joints, shears, and shear zones accounted for significant differences in the

Jan 1, 1974

By B. Denby, D. J. McMlarnon

During the ongoing research into the possible applications of Virtual Reality in underground operations, the AIMS Research Unit has developed a user-interface driven program which enables a user to input the geometry of underground mines, and add equipment and working processes in order to produce an accurate simulation of their operation. This paper describes the main features of this system (VR-MINE). Virtual Reality is a field which has grown out of three dimensional computer graphics techniques, and allows a user to move freely around a model held within the computer's memory. Movement around this model is carried out by the use of intuitive peripherals such as joysticks, with the user's view from their position within the model being produced in real time on a computer monitor or other device (such as a headset). This enables a user to interact with any three dimensional model and see the results of their actions immediately. VR-MINE is broken into two separate programs, both running under Microsoft Windows 3.1 or above. The first, the editor, allows the user to develop the mine layout and add equipment and personnel. The mine geometry is considered to be made up of various types of objects, for example a straight roadway segment which can be inclined, a junction roadway segment, and a turning segment. The geometry can then saved into a file to be loaded in by the second program of VR-MINE, the viewer. This generates a real- istic representation of the mine, with undulating floors and walls. It also has the ability to display multiple windows on the mine at the same time, which are arranged interactively. The simulation occurs within this program, with the user traversing the model in real time to examine possible areas of improvement in operations. This paper gives a number of examples of how the AIMS Re- search Unit has applied this technology to a range of underground mining scenarios to improve the safety of workers in the under- ground environment. The application discussed include computer graphics and Virtual Reality systems to training, risk analysis, visualisation, simulation, accident investigation and major hazard planning.

Jan 1, 1996

By A. F. Stewart

Slope design in an open pit mine includes the determination of a number of parameters, including bench height, bench face angle and berm width. By way of a case history of two highwall slopes (160m and 220m high) excavated in dipping strata in an operating coal mine, this paper illustrates the influence that bench face angle can have on the stability of an entire slope. The two highwall slopes, the lower of which experienced significant instability, were excavated in essentially the same lithologic and structural environment, with the main differences between the slopes being the angle at which the bench faces were excavated and the excavating methods that were employed. In addition to describing the instability that occurred on one of the pit walls, relevant aspects of the engineering geology, slope design and excavation procedures are described.

Jan 1, 1998

By M. G. Hester, G. S. Adisoma

To address the problem of grade estimation in a general three-dimensional shape and the uncertainty associated with the estimate, the technique of jackknifing/ block-kriging shortcut is proposed. A new estimator called jackknife kriging is introduced first. Through the jackknife variance, a confidence limit for the reserve-grade estimate can be calculated. Unlike the kriging variance, which is more a measure of data configuration and which is independent of data values, the jackknife variance reflects the true variability of the data. This approach provides a simple way to set a confidence level for global estimation of resources.

Jan 1, 1997

By John S. F. Dunlop

One of the more difficult problems frequently facing geologists and mining engineers is that of estimating the ore reserves of mineral deposits. Cost conscious mining operations invariably require an accurate knowledge of tonnage and grade for both short and long term planning. A case study is presented, showing how a classical frequency distribution was fitted to a population of drillhole assays. Using these results, a grade- tonnage curve is derived using the Lasky expressions, and the results discussed. A geostatistical analysis is then presented. First, variograms are drawn, models fitted to them and analyses made of drift and anisotropy. Second, simple block kriging is carried out and the results plotted on large 1000 scale plans, suitable for overlay with routine .mine plans. Kriging results are verified using two independent techniques: random kriging on a regular grid and inverse distance weighting. Finally an attempt is made to optimize the drilling grid, and to fully tabulate the total computer running costs for the work described.

Jan 1, 1979

By R. Kramer, A. Habibi

A ventilation survey was conducted in an underground longwall trona mine. The mine is relatively shallow and categorized as a gassy mine. The ventilation system includes three intake and six exhaust shafts, and three surface axial fans ventilate the mine in a blowing configuration. Airflow quantity, pressure losses and air psychrometric characteristics were quantified, and the influence of moving cages and skips in the shaft examined. The benefits of utilizing high-accuracy digital pressure transducers and advanced psychrometers were seen when undertaking a “leapfrogging” survey to gather data needed to build a computer ventilation model. Two underground booster fans with VFDs are idle but available at the mine. The ventilation model was used to determine the optimal booster fan locations to decrease operating cost by reducing the load carried by the main fans. A leakage study was conducted to evaluate the effects on the system of additional pressure from a booster fan. The study finally prepares a future ventilation model for the next 15 years of mine operation and investigates the effect of proposed scenarios.

Jan 1, 2014

By Lit-Mian Chan, David H. Carlson, John H. Johnson

This paper presents an apparatus and procedures to implement a methodology for controlling ambient air quality in a confined working environment, such as an underground mine, an underground storage area, or a tunnel. The air quality control methodology is directed at limiting the quantities of exhaust pollutants emitted by diesel-powered vehicles into the confined space by identifying vehicles that are excessive polluters. The methodology is based on tailpipe and ambient air measurements in the confined space, and the ambient air threshold limit values (TLVs) for the various diesel exhaust pollutants. The methodology consists of two computational methods; a deterioration criteria computational method to identify excessive polluting vehicles, and an engine performance computational method to determine engine performance and to provide information needed to diagnose engine faults. The methodology is designed for implementation in conjunction with a preventive maintenance program. The first part of the paper describes the mine air and tailpipe emissions measurement apparatus and techniques used to obtain data. This is followed by sections discussing the deterioration criteria and the engine performance computational methods. A section discussing some common engine emissions-related faults is also presented. Lastly, a proposed procedure to implement the methodology including a possible hierarchical structure for mine personnel involved to implement the procedures is presented.

Jan 1, 1993

By D. Williamson

In the post war years metals analysts and statisticians have generally tracked the demand for metals in line with changes in OECD industrial production (IP) growth rates because, undoubtedly, the correlation between IP growth and metal demand was reasonable. However the correlation was exaggerated. During times of expanding IP growth metal demand increased at a faster proportional rate than IP growth. This was probably due to industry restocking in anticipation of growing demand at the start of each economic cycle. Conversely, metal demand would slacken at a greater rate than would be suggested by negative IP growth as industry destocked in order to reduce costs. Nonetheless, overall, a reasonable correlation between IP growth, over the longer term, and metal demand could be painted. Yet, although this correlation has stood well since the last world war it has been based on the fact that the bulk of the world's IP growth stemmed from the industrialized countries of the western world, latterly including Japan. The so called "developing world" was of little consequence, whilst countries of the Soviet Union and Communist Bloc were deemed to be closed, self-contained entities which, for each metal, would either be net exporters or importers. These quantities would be used by analysts to calculate the overall supply/demand equation for the western world only and to deduce whether a commodity was in shortage or surplus. It is now believed that this method of projecting total world supply and demand for raw materials is outdated and takes little account of the worldwide political changes which have occurred since the collapse of communism and the revitalization of China, albeit under a notional communist government. It is no longer appropriate to assess global balances for raw materials on the basis of three economic blocs namely, western world, developing world and communist bloc. Rather, global balances need to be projected on a global basis. In this regard, since the collapse of communism and the removal of many other totalitarian regimes, capitalist forces are at work and are attempting to satisfy, with some considerable success, the expectations of the great mass of the world's poorer people. Such people, usually located in Asia, Africa and Latin America have aspired to the same standard of living as people living in western Europe, North America and Japan. Now, with free market forces at work their aspirations will start to be met. Consequently, the demand for metals and other raw materials will now rise at a much faster rate than at any other time in the world's history. Not only will the production of raw materials have to keep pace with rising IP in the developed world but will also have to keep pace with the demands associated with the rising expectations of rapidly increasing populations in the developing world, as well as from within the old communist bloc countries. This paper sets out to argue the case that metal demand could well increase at a rate faster than the world's mining companies, governments and financiers can deliver.

Jan 1, 1997

By W. Stahl, K. Keller

In addition to classifying bulk material, vibration screens are commonly used in dewatering. However, the lack of a comprehensive physical theory of dewatering often leads to difficulties in the design and operation of the vibration screens. First, in this report, the dewatering of bulk material are shown based on a physical model. Because of tile oscillatory motion of the liquid in the bulk, the inertial force of the accelerated liquid and the dripping of water out of the bulk or screen must be taken into special consideration. The physical model put forward shows the effect of the various operations parameters of dewatering screens. A comparison between dewatering theory and practice are shown by measurements using coal, limestone, etc. Dewatering measurements conducted on a vibration screen demonstrated that different vibration frequencies and rates of acceleration lead to different residual moistures. Finally, the possibility of improving vibration dewatering is described.

Jan 1, 1998

By R. Day

Nahcolite is a naturally occurring sodium bicarbonate mineral found principally in the Piceance Creek Basin of northwest Colorado. An 8-m thick nahcolite bed, 610 m below the surface, is the target of this first commercial nahcolite mine. A chamber and pillar mining system is developed by solution mining parallel 8-m tall by 18-m wide by 450-m cavities initiated along horizontally drilled holes. Hot water leaching, cooling crystallization and flash drying is the process. The sodium bicarbonate product is consumed by the baking, animal feed, industrial and acid rain abatement markets. A project overview, emphasizing the combination of horizontal drilling and solution mining technologies, will be presented.

Jan 1, 1994

By R. K. Will

An inactive mining operation in northern California is known to be a source of acid mine drainage and heavy metals which have impacted adjacent creeks. Elevated concentrations of copper and zinc are a concern to aquatic populations, particularly steelhead trout and salmon downstream in the Sacramento River. Previous regional geological surveys of mineralization by the U.S. Geological Survey located and mapped outcrops of massive sulfides and gossan. Recent investigations indicate that a substantial amount of the metals in the local creeks are due to natural causes. The investigations include locating and mapping surface and subsurface minerals, soil and water sampling, and chemical analysis. Groundwater, seeps, and surface water were also sampled and analyzed. A water balance was conducted on a sub-basin level following delineation of surface water drainage and groundwater divides. A chemical mass balance incorporated metal concentrations and water volumes and was then used with other data to determine the contribution of metals from natural versus mining-related causes.

Jan 1, 1998

By Greg Barfoot, Kurt Keskimaki

The Henderson Mine is located approximately 50 miles west of Denver, Colorado. A project is underway to replace the existing rail system which transports molybdenum ore 15 miles from the mine to the mill using three flight conveyor system. The first conveyor is a 1 mile, high lift conveyor which transports the ore from an underground crushing station to the end of the existing rail tunnel. The second conveyor is 10 miles in length and utilizes the existing rail tunnel to transport the ore from the mine, which is on the east side of the Continental Divide, to the mill located on the west side. The third conveyor takes ore from the tunnel portal to the mill through a series of 7 horizontal curves and inclines up to 15 degrees. The project applies advanced conveyor design to tackle the installation of the system in an operating mine and achieve the highest possible level of reliability. This paper outlines the design process for this system, discusses the options which were evaluated and how the current design evolved.

Jan 1, 1998

By Mike L. Aziz, Keith D. Ferguson, Glenda Ferris

The Equity Silver mine has been a severe producer of Acid Rock Drainage (ARD) since 1982. The mine was closed in 1994 and a compacted clay cover installed, but ARD continues to be produced. Three permanent employees manage the collection and treatment system at the site. The site still poses a significant environmental risk to the environment and downstream users and requires a high level of diligence. Various stakeholders' perspectives of the risk posed by Equity, and what constitutes acceptable risk, will be examined in this paper from a company operation staff, corporate environmental manager and downstream environmentalist perspective.

Jan 1, 2000

By P. Hornby, S. Henley

INTRODUCTION The project described in this paper is designed to provide a standard and flexible method by which data can be exchanged among different systems and packages in common use for geo- logical modelling and mine planning, with substantial savings in ad hoc programming which is expensive and produces interface software that is difficult to maintain. Such packages include specialised applications such as Vulcan, Surpac, Datamine, and Gemcom software, and the Whittle pit optimisation programs, and more general products such as AutoCad, Microstation, and Maplnfo, and database management systems through a generic SQL interface. The data translator is built around the CSIRO Data Model and GeoEditor, and will make widely available the benefits of the Data Model by adding functionality to its implementation in an industry- standard language and style, with interfaces to important geological and mining software products used by the industry, while including also the visualisation and editing capabilities of the GeoEditor which provides the functional framework within which the Data Translator is developed. The Data Translator is intelligent in the sense that it is not a black-box solution but allows visualisation and validation of data during transfer; furthermore it provides a means for changing abstraction levels during the transfer operation. There have been few similar efforts to address this problem. It is not a problem which is likely to be solved in any general or long- term way by any individual commercial software vendor. THE CSIRO DATA MODEL A wide variety of software tools have entered the exploration and mining industries via different pathways. Examination of these pathways and the origins of the software illuminates the types of data transfer problems and difficulties which might occur in the day to day life of exploration and mining operations. In exploration, the focus is normally on a large area (>5000km2) which is explored primarily in two dimensions. For 20 exploration purposes, geographical information systems (GIs) software, image processing software, and, in some cases, 20 computer aided design (CAD) software have been employed. Typically, GIs soft- ware is used the most by lands and tenements personnel and government geological survey organisations, image processing software is used the most by geophysicists, and 20 CAD software is used the most by drafting and geology personnel. In contrast, within the mining environment, almost all activities have 3D character. In this realm, 3D CAD software and specialised mine planning and design software are important. Specialised mine planning and design software is similar to 30 CAD software, but typically has additional capabilities such as specialised modules for surveying, drill hole data operations, open pit design and optimisation, underground mine design, mining block model creation, and/or ore reserve calculations. Unfortunately, the different origins of the software in exploration and mining lead directly to problems in data exchange and the design of seamless software systems. These problems result from the different data management strategies employed by the different classes of software. In order to address these problems, CSIRO Exploration and Mining and CSIRO Division of Information Technology have been investigating the structure, character, and syntax of data and soft- ware present in computer-aided exploration and mining activities since early 1993. The goal of this effort is to 1) systematically ex- amine the breadth and depth of the data in use within exploration and mining, and to 2) promote a data organisation strategy which is broad enough and comprehensive enough to enable wiser soft- ware design and easier data transfer. In the short term a data model can be used to improve data transfer; in the longer term it is hoped that a data model framework will help object-oriented concepts to enter the next generation of geoscientific software. The data model is described in more detail by Power et al., 1995. THE DATA TRANSLATOR PROJECT The CSIRO Data Model provides a basis for a very wide range of applications in geology and mining. It has been developed over the past two years by a joint team from the Division of Exploration and Mining and the Division of Information Technology, and its principal purpose is to provide a comprehensive and self consistent model of the geometric and topological properties of geological and mining data. The project is being carried out by CSIRO with the support of Australian mining companies through AMIRA (the Australian Mining Industries Research Association). Eight companies are sup- porting the project : • North Ltd Minenco • MIM Exploration • Fractal Graphics • BHP Australia Coal • Pacific Coal • Gencor CRA Exploration The systems to be interfaced have been decided by comparing the priorities of the various sponsors, to produce a final combined priority list as follows : • Vulcan • Minescape • Micromine • Mapinfo INTRODUCTION The project described in this paper is designed to provide a standard and flexible method by which data can be exchanged among different systems and packages in common use for geo- logical modelling and mine planning, with substantial savings in ad hoc programming which is expensive and produces interface software that is difficult to maintain. Such packages include specialised applications such as Vulcan, Surpac, Datamine, and Gemcom software, and the Whittle pit optimisation programs, and more general products such as AutoCad, Microstation, and Maplnfo, and database management systems through a generic SQL interface. The data translator is built around the CSIRO Data Model and GeoEditor, and will make widely available the benefits of the Data Model by adding functionality to its implementation in an industry- standard language and style, with interfaces to important geological and mining software products used by the industry, while including also the visualisation and editing capabilities of the GeoEditor which provides the functional framework within which the Data Translator is developed. The Data Translator is intelligent in the sense that it is not a black-box solution but allows visualisation and validation of data during transfer; furthermore it provides a means for changing abstraction levels during the transfer operation. There have been few similar efforts to address this problem. It is not a problem which is likely to be solved in any general or long- term way by any individual commercial software vendor. THE CSIRO DATA MODEL A wide variety of software tools have entered the exploration and mining industries via different pathways. Examination of these pathways and the origins of the software illuminates the types of data transfer problems and difficulties which might occur in the day to day life of exploration and mining operations. In exploration, the focus is normally on a large area (>5000km2) which is explored primarily in two dimensions. For 20 exploration purposes, geographical information systems (GIs) software, image processing software, and, in some cases, 20 computer aided design (CAD) software have been employed. Typically, GIs soft- ware is used the most by lands and tenements personnel and government geological survey organisations, image processing software is used the most by geophysicists, and 20 CAD software is used the most by drafting and geology personnel. In contrast, within the mining environment, almost all activities have 3D character. In this realm, 3D CAD software and specialised mine planning and design software are important. Specialised mine planning and design software is similar to 30 CAD software, but typically has additional capabilities such as specialised modules for surveying, drill hole data operations, open pit design and optimisation, underground mine design, mining block model creation, and/or ore reserve calculations. Unfortunately, the different origins of the software in exploration and mining lead directly to problems in data exchange and the design of seamless software systems. These problems result from the different data management strategies employed by the different classes of software. In order to address these problems, CSIRO Exploration and Mining and CSIRO Division of Information Technology have been investigating the structure, character, and syntax of data and soft- ware present in computer-aided exploration and mining activities since early 1993. The goal of this effort is to 1) systematically ex- amine the breadth and depth of the data in use within exploration and mining, and to 2) promote a data organisation strategy which is broad enough and comprehensive enough to enable wiser soft- ware design and easier data transfer. In the short term a data model can be used to improve data transfer; in the longer term it is hoped that a data model framework will help object-oriented concepts to enter the next generation of geoscientific software. The data model is described in more detail by Power et al., 1995. THE DATA TRANSLATOR PROJECT The CSIRO Data Model provides a basis for a very wide range of applications in geology and mining. It has been developed over the past two years by a joint team from the Division of Exploration and Mining and the Division of Information Technology, and its principal purpose is to provide a comprehensive and self consistent model of the geometric and topological properties of geological and mining data. The project is being carried out by CSIRO with the support of Australian mining companies through AMIRA (the Australian Mining Industries Research Association). Eight companies are sup- porting the project : • North Ltd Minenco • MIM Exploration • Fractal Graphics • BHP Australia Coal • Pacific Coal • Gencor CRA Exploration The systems to be interfaced have been decided by comparing the priorities of the various sponsors, to produce a final combined priority list as follows : • Vulcan • Minescape • Micromine • Mapinfo • Medsystem

Jan 1, 1996

By M. Lotfi

The criteria for evaluating equipment operator performance were identified as the changes in reaction time, the changes in physiological responses, and the changes in subjective reporting of stress. Data were collected while the Subjects operated a front-end loader simulator. This report out-lines the components and the tasks generated by the simulator. It explains the simple and basic assumptions underlying the design of the simulator and the methods of data collection. Improvements that can facilitate the collection of data, including the connection of the simulator to a portable personal computer for on site use are discussed. Statistical analysis of data showed significant deterioration in performance. The report concludes that operator performance can be measured and improved. This report shows that the operator tasks can be simulated by means of simple simulators, the complexity of which is determined by the availability of funds and the area of interest of the investigator.

Jan 1, 1989

By E. Sabah

A series of adsorption tests are carried out to understand the ability of cationic surfactants and metal ions to adsorb onto sepiolite. Adsorption tests conducted as a function of heat treatment reveal that sepiolite is rather conducive to the uptake of both organic and inorganic ions. An ion exchange mechanism between surfactant or metal cation and magnesium ion followed by chain-chain association is proposed to explain the incorporation of cationic surfactants into the structure of sepiolite.

Jan 1, 1998

By D. Sinha

Mine investment decisions involve both objective and subjective criteria. The subjective criteria are efficiently decided by interaction with company experts. The Expert System approach can incorporate knowledge of experts and interact with conventional computer programs on mine evaluation. Artificial intelligence offers considerable opportunities in comprehensive mine investment decision making process.

Jan 1, 1998

By Frank H. Skelding

A new, large mine is about to be born. Many years and millions of dollars have been invested in exploration. An orebody has been found and proven. All necessary political and legal work to establish rights and conditions for development are complete. The feasibility studies are favorable. Financing has been arranged. Board approval has been given to proceed. The time has come to engage a contractor to design and build the new facilities in a location, as is the common case today, far re¬moved from the centers of advanced technologic development where the minerals will ultimately be used. A select list of Engineering and Construction (E&C) companies is asked to prepare proposals. At this point the common viewpoint among mining companies is that the company's sole remaining problem, a major one to be sure, is to select qualified contractors to design and build the project at the lowest cost and shortest time possible so that production can start generating a return on investment. The purpose of this discussion is to explore the viewpoint of the large E&C contractor toward such projects. It differs in important ways from that of the client mining company and it is these differences and the reasons for them that must be understood by the client if severe difficulties and misunderstandings with the contractor, starting at the beginning of contract negotiation and continuing through design and construction to final startup are to be avoided or minimized. Often enough, the difference is in degree, not kind, which only serves to obscure the fact that a difference exists.

Jan 1, 1975

By William L. Carter

Through your presence here this morning and your membership in the Society of Mining Engineers, you have shown that you are interested in keeping abreast of the latest technology and mining procedures, want to be part of the continuing progress made by those in your profession, and are looking for ways to participate in expanding your professional and personal experiences and skills. All of these factors are part of your continuing education, the need for peer identification or recognition, and the desire to make a specific contribution to strengthening your profession. However, you may be here with or without your company support and financial backing, unless you are self-employed. Whether you are here for the above reasons, or for many others, your presence reflects a recognition of the importance of participating in the organizational structure of your profession.

Jan 1, 1981