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By Peter C. Ashbrook

The Regional Copper-Nickel Study was initiated in large part because of fears that copper-nickel development might cause adverse effects on the environment from air pollutants such as sulfur dioxide (SOZ) emissions from a smelter, and water pollutants such as acid mine drainage. The Study comprehensively examined the potential for ad- verse effects on the environment and possible mitigation measures on both a local and regional scale by first characterizing existing air and water quality, and existing sources of pollution, and then developing hypothetical development scenarios to model potential adverse effects. This paper gives a brief overview of the Study's findings concerning air and water resources.

Jan 1, 1980

By Stuart Brashear, J. W. Reil

The manuscript of this paper was not available for publication when the Proceedings went to press. Should the authors elect, they may distribute copies at the time of the Symposium.

Jan 1, 1986

By T. J. Carew

INTRODUCTION The application of micro-computers to the evaluation of an advanced exploration project is illustrated by reference to a large project in the Sudbury Basin region of Canada. The deposit in question is polymetalic (Cu, Pb, Zn, Au, Ag) with a strike length of 3048m (10000ft) and has been explored to a depth of 457m (1500ft) by approximately 1350 diamond drillhole of between 9 - 305m (30-1000ft) in length. The large amount of data involved and the ability to rapidly recalculate geological reserves in response to fluctuating metal prices were key factors in the application of a micro-computer based evaluation system. The evaluation software was implemented at two levels, with data capture implemented mainly on - an entry level workstation comprising an IBM-PC compatible (PC-XT) micro-computer equipped with a 20Mb hard disc, printer and RS-232 serial communication facilities. Data analysis, display, geo- logical modelling and processing was carried out on a high-level workstation based on a Hewlett-Packard 9000 super- micro computer and peripherals, including a 40Mb hard disc, tablet digitizer and plotter. Basic drillhole data was entered either directly at the super- micro or transferred from the PC via the RS-232 link. The evaluation process proceeds once the data is edited and in a "clean" format within a master project database. The software is comprised of a suite of modular, integrated programs based on ease of use, interactive graphics and optimized for the computer workstation. Drillhole data was displayed and plotted as hard copy plots on which geological interpretations were developed. The data was copied into small manageable projects consisting of 100 to 150 drillholes, within which a sectional model was created such that all the models are interconnected along the entire strike with no overlaps. Geological reserves were derived by developing a set of function variables, including Net Smelter Return, within the database. The values of these functions can be displayed on the model sections and "ore” zones defined in accordance with pre-determined cutoff values. Interpolation of the modelled data was then carried out and geological reserves calculated and reported. DATA CAPTURE Drillhole data for the project consisted mainly of existing drillhole logs, although the system allows for the entry of new information as it becomes available. The structure and format (i.e. number and length of variable fields) is user defined. The log for this project comprises an abbreviated section for name, competency, grain size, texture, colour and alteration. Fields are defined for structural information regarding bedding and fault angles and up to seven mineral identification columns and percentages are available. Assay information consisting of the sample number, width and six determinations (Cu%, Pb%, Zn%, Fe%, Au opt., Ag opt.) along with a comments section of 25 characters completes the log. One powerful feature of the data- base is the ability to set up function variables that are mathematical and/or logical combinations of the project variables, enabling the user to develop economic variables such as Net Smelter Return. These functions include current treatment costs, deductions and penalties and can be rapidly recalculated within the database to accommodate changes in metal prices, forecast recoveries and exchange rates (Table 1).

Jan 1, 1987

By C. F. Curry

In the early 1940's Humphreys Mining Company in Florida pioneered heavy mineral mining with a dredge in the United States, In 1948 Du Pont, in conjunction with Humphreys, opened their first of two mining operations recovering a titanium dioxide product in Florida. Later on in 1952 Du Pont opened their second plant, both of which used a cutterhead suction type of operation. This process is also used in heavy mineral mining in Australia and Africa. In 1957 ASARCO started prospecting in New Jersey. Test borings indicated a large deposit of ilmenite bearing heavy mineral sands had been deposited and concentrated in an area near Lakehurst in central New Jersey. Humphreys Mining Company was contacted about the possibility of mining the ASARCO New Jersey property in much the same way as Du Pont and themselves were doing in Florida. An extensive study was made to determine the economic feasibility of mining the ASARCO property. During this study, extensive test drilling and samples for a pilot plant were taken.

Jan 1, 1975

By Kathleen Y. Knoebel

This paper describes a graphical mini computer system called MPASS 2 (Mine Performance Analysis/Simulation) which has been designed to conduct analysis of underground room-and-pillar mining operations using both conventional and continuous mining methods. Dynamic, graphic displays of mine face machine activities are presented on the CRT screen to provide extensive visibility into underground mining activities. MPASS 2 consists of: an interactive inputting system that graphically creates a room-and-pillar mine and describes the mine when production is initiated; a time-step simulator that produces statistical summaries of shift activities and uses CRT screen graphics for accelerated-time display of machine activities and delays; a statistical analysis subsystem for analyzing mine performance data; an industrial engineering system that permits users to enter actual machine activity statistics and replay mine operations on the CRT screen; and a data management system to store historical performance information on mine characteristics and operations. MPASS 2 operates on a Hewlett-Packard 9845B mini computer with 450 K bytes of extended memory, and is written in H-P BASIC. It has been installed at Freeman-United Coal Mining Company in West Frankfort, Illinois and at the U. S. Department of Energy Pittsburgh Mining Technology Center. Applications include production system simulation, industrial engineering analysis, production scheduling, new equipment evaluations, and training.

Jan 1, 1982

By G. O. Kesse

The Republic of Ghana, located on the West Coast of Africa, is one of the West African countries rich in bauxite deposits. The main occurrences of bauxite deposits are at Sefwi Bekwai in the Western Region, Aya-Nyinahin in the Ashanti Region, Atewa Range near Kibi and at Mount Ejuanema both in the Eastern Region of Ghana. These bauxite deposits belong to the so-called blanket deposits as they are associated with erosion surfaces of old peneplains and occur as cappings on the flat tops of hills or mountains whose heights are generally greater than 600 metres above sea level. These deposits can also be classified as laterite-silicate bauxites since they have been formed under tropical weathering conditions. Genetic and mineralogical investigations have revealed that all bauxite deposits of Ghana are the result of indirect bauxitization processes, for the minerals of the weathering parent rocks have not been transformed directly into gibbsite. In all cases, lithomarge of kaolinitic clay can be recognised. The geology of the major occurrences of bauxite in Ghana shows that the Mount Ejuanema deposit is the only deposit associated with the Voltaian System of rocks. This rock System consists mainly of sandstone, shale, mudstone, conglomerates and pebbly beds. All the otter deposits are associated with the Birimian System of rocks which are made up of metamorphosed lavas,pyroclastic rocks, hypabyssal basic intrusives, phyllites, schists, tuffs and greywackes.

Jan 1, 1984

By Penglu Gan, Jinjie Zou, Chenglang Pan, Xiaowu Tang, Yu Zhao

"The north segment of the Zizhi Tunnel that consists of twin tunnels was excavated at a shallow depth in soft ground using the Shallow Tunneling Method. Based on continuous field measurements, the development histories of surface settlement were analyzed first. The observed development process could be roughly divided into three stages and the influence of river was evidenced. Transverse and longitudinal surface settlements above the twin tunnels were then fitted with empirical models. The obtained trough width parameters in transverse and longitudinal direction (it and il) and the volume loss (VLs) were presented and discussed. Additionally, surface settlement was compared with the crown settlement. The relationship between surface and crown settlement behaved in two different ways inside and outside the river-affected region. The findings in this project give references for predicting surface settlements in similar tunneling condition. INTRODUCTION Nowadays tunnel construction has become a major way of utilizing underground space in many large cities. The ground deformation will be inevitably induced in the tunneling process. Engineers should always be careful about excessive deformation that may damage adjacent structures. For shallow tunnels, controlling ground deformation turns to be more risky. Since soil arching is not completely formed in the shallow tunneling, settlements can easily develop from tunnel crown to ground surface.A conventional tunneling method named Shallow Tunneling Method (STM) has been developed and widely applied to constructed shallow tunnels in China. The major difference between this method and the New Austrian Tunneling Method (NATM) is whether considering self-supporting capacity of surrounding ground or not. In order to reduce the disturbance of surrounding soils, several guidelines are highlighted in this method, including advanced pipe forepoles, strict grouting, short excavation length, strong support, quick closure and frequent measurements (Fang 2012). Nevertheless, the ground deformation is still hard to control and becomes a concerned problem, mainly because ground settlement has some regional features and largely depends on the detailed excavation methods (bench cut method, multiple heading method, etc.) and ground condition (sand, clay, decomposed rock, etc.)."

Jan 1, 2016

By James J. Scott

Shale formations are the Nemesis of the Mining Engineer. Shales react to changes in environment in the most unusual and unpredictable manner. Increase in temperature may cause spalling, increase moisture and compression induced fractures may occur, and if a full face is exposed it may deteriorate due to atmospheric exposure. Combine only small amounts of shale in layered fashion with hard brittle competent rock and the whole structure may be fractured and fail due to stresses generated in and around the shale. In this paper the author will discuss failure mechanisms encountered under various field conditions and remedial action which may be employed by the engineer.

Jan 1, 1969

By R. Bruce Thorndycraft

Pinson Mining Company was formed to develop a gold orebody located in northern Nevada near Winnemucca. A feasibility study was undertaken in 1979 by a consortium of three Toronto-based mining companies and a Reno-based exploration company. The study indicated a viable project with gold priced above $225 per ounce. A project manager, and mine and mill superintendents, were hired in late 1979 to expedite the development of a 1000 ton per day mine-mill complex. Plant design engineering was contracted with Industrial Design Corporation in Salt Lake City. Three experienced plant metallurgists representing Pinson were stationed in Salt Lake to guide the work of Industrial Design. Among the many design criteria spelled out by Pinson, foremost were bringing the mill on line as quickly as possible at minimum capital cost. Fourteen months after the beginning of design engineering, the completed Pinson mill became operational. Total capital cost, including mine development, was $18 million. The Pinson project has proved to be far more than viable; the entire capital cost will be recovered within 18 months of the mill start-up.

Jan 1, 1982

By W. E. (Bill) Stanley

Introduction This is an exciting day. It isn't often that you can find the best minds in a particular business gathered together in one place. But that is what we have here. You are the best and the brightest people there are in the business of gold mining. What we discuss at this conference confirms the major issues facing us and sets out the issues governing how our mines and mining companies will be run in the next few years. In looking over the list of papers to be given, I have noticed something. It is something that I have noticed at almost every mining convention I have ever attended. Almost every paper at this conference concerns itself with the technical side of mining. Most of us in this roan are professionals; we are either engineers, geologists, accountants or representatives of some other profession. In getting where we are today, we have had to work hard to acquire the technical skills needed for our individual professions. We are all proud of our knowledge and work hard to claim the right to be considered an expert in a particular technical field or subject area.

Jan 1, 1987

By T. H. Dubaniewicz, J. E. Chilton

The U. S. Bureau of Mines is investigating the application of fiber optic technology to methane and carbon monoxide monitoring. A methane monitoring system is described that is based on differential absorption of infrared light. It can detect concentrations as low as 0.2% and as far away as 2 km via fiber optic cable. The upper range is 100% methane. The system requires no electrical power within the mine so it should operate safely under mine disaster conditions. A hybrid carbon monoxide monitoring system is described that combines a low-powered electrochemical cell with fiber optic telemetry. Testing has shown the system can operate maintenance- free for several months.

Jan 1, 1992

By L. S. Harris

The application of briquetting in various chemical, mineral, mining and metallurgical processes has been rapidly increasing in the past two decades. This is, in part, due to the development of new, more economical and higher performance briquetting equipment. Some of these developments, which have reduced the operating and maintenance costs,, include anti-friction bearings, hydraulically applied pressure enclosed and sealed gearing and bearings, tapered predensification feed screws, water cooling and materials of construction capable of operating at temperatures up to 18000F, and control systems capable of maintaining optimum briquette quality control. The briquets can be formed into almost any desired size and shape, To date, with present rotary briquetting presses in the 25 to 500 ton force range, briquets from 1/4" to 6" length are presently being used, some of which are illustrated in Figure No. 1. In force fed rotary briquet machines, these shapes are produced by feeding the material in between a pair of counter rotating rolls, as illustrated in Figure No. 2. The rolls have forming dies indented into their circumferential surface, as illustrated in Figure No. 3.

Jan 1, 1973

By Michael Bourassa, Sonja Felderhof, Normand Champigny, Steve Vaughan

Introduction -Comparison of International Reporting Standards (Sonja) -Legal and Due Diligence Requirements for Reporting (Steve) -Flexibility to Recognize International Reporting Standards (Michael) -Obligation of SRO’s to Discipline (Michael) -Impact of Sarbanes Oxley on Reporting (Normand)

Jan 1, 2003

By Fathi Habashi

SOLVENT EXTRACI ION involves two operations: 1) Extraction The metal values in the aqueous phase are extracted by agitation with an organic solvent immiscible in that phase. The two phases are then allowed to separate; the aqueous phase is discarded or recycled and the loaded organic phase saved.

Jan 1, 1970

By Shuji Owada, Keisuke Yasukawa

Electrostatic and/or high tension separation has been used for the separation of rare metal bearing minerals, foods, industrial wastes and so on. Since the separation is achieved by the difference mainly in surface conductivity of particles, the efficiency in humid circumstances is very low, and then, the applicability is considerably limited. We applied the following two-stage pretreatment technique to the separation process, which involves (1) adjustment of surface wettability by adsorbing surfactant on the particle surface and (2) control of the surface conductivity by spraying with electrolyte aqueous solution. The addition of this pretreatment technique has been found to have a great advantage over conventional methods. Separation efficiency is achieved even in humid circumstances and selectivity can also be obtained between insulator minerals. The selectivity is very similar to that of flotation in wet process. This separation technique will be applied not only to mineral processing but the processing of industrial waste such as electric and electronic waste materials.

Jan 1, 1995

By R. W. Brann, R. C. Freas

Franklin Industrial Minerals operates several mines/quarries, including two room and pillar underground mines. Both of these mines are operated as multiple level room and pillar including heading and bench operations on one or both of the levels. This paper focuses on Franklin’s Crab Orchard, Tennessee mine, which produces both high purity chemical grade limestone and crushed stone for construction applications. The high purity chemical specifications for the chemical grade limestone and filler/extender applications are inconsistent with the non-chemical rock being produced to supply the crushed stone market. As a consequence Franklin has developed a unique mine plan and operation to maintain both product balance and a safe and stable working environment.

Jan 1, 2003

By Zhongxue Li, Baolu Zhou, Yiqing Zhao

"Rare earth elements (REEs) are a kind of new materials which have excellent optical, electrical and magnetic properties, and they play an important role in the development of high technology and green energy industries. With abundant reserves and a wide range of REE type, rare earth industry has a rapid development in China in recent years. However, environmental issues associated with REE exploitation have severely restricted the sustainable development of rare earth industry in China. At present, literatures on the externalities of REE exploitation are very limited, especially in China. This paper builds an evaluation model based on life cycle evaluation to estimate the external costs of REE exploitation at Bayan Obo. The results show that the external costs for producing one metric tonne of rare earth oxides (REO) in Bayan Obo was CNY 34739 in 2013, the external costs of waste gas, waste water, radioactive substance, REE resource depletion, and land occupation are CNY 14945, 12515, 1400, 3199, and 2680, respectively. Waste gas and water constitute about 79% of the total external costs. The internalization of the external costs would reduce the financial profit of Northern Rare Earth (Group) by 18%. This study has taken into account only those externalities whose market values can be estimated, and therefore the external costs of REE exploitation in Bayan Obo is likely to be underestimated. The results fill the gap in literature and provide further understanding on the external cost of REE exploitation.Introduction / Background Along with increasing concern about environmental pollution problems caused by the usage of fossil fuel and the shortage of fossil energy, a transition has occurred where development has moved toward green and renewable energy sources with less pollutant emissions (Stegen 2015). Rare earth elements (REE) are a group of important raw materials for these trends since they have unique magnetic, electronic and optical properties, and thus make them widely used in making high-performance magnets and energy saving lamps (U.S. DOE 2010). In addition, REE are crucial for manufacturing of widespread high-tech applications in medical, defense and electronic industries. Many countries have made medium-term and long-term plans for the development of their REE industries, and the annual growth rate of global REE demand is expected to increase by 6% by 2020, and reach about 170,000 metric tons of rare earth oxides (REO) by 2020 (Rollat et al 2016)."

Jan 1, 2017

By Paul M. Godlewski, Roberto J. Guardia

Hundreds of highway and rail transportation tunnels in North America have been rehabilitated in the last two decades. Tunnel rehabilitation is usually dictated by an owner’s need to extend the working life of the structure, but typically has the added benefit of increasing capacity (greater speed or increased clearance) and enhancing safety. Not only has rehabilitation proven to be an economical alternative to new tunneling, but it can be safely accomplished by working during short work “windows” without taking the tunnel out of service. This paper presents methodology for planning and designing of tunnel rehabilitation projects, and case histories illustrate successful excavation and support technologies.

Jan 1, 2003

By K. K. Cheng, Z. M. Chen, A. L. Mular

INTRODUCTION Since the nineteen fifties, process engineers have been seriously concerned with process models for various purposes (1,2,3). Models serve as subroutines to mathematical flowsheets which simulate circuits of interest. Simulators can serve to increase process know- ledge, assess circuit performance, investigate flowsheet modifications, evaluate new flowsheets, perform off-line optimization, and compare alternative control strategies. This chapter describes a methodology to develop a simulator of a bulk Cu-Mo circuit comprised of roughers, scavengers and 3 stages of cleaning. The simulator was employed to evaluate the influence of water addition at circuit points and to estimate the optimal number of cells for each stage in the circuit. DESCRIPTION OF CIRCUIT Figure 1 is a flowsheet of the Brenda Mines Ltd. (located near Peachland, B. C.) bulk Cu-Mo flotation circuit as simulated prior to an expansion/renovation which involved the installation of large, new flotation cells. Referring to the flowsheet, feed to rougher cells includes fresh feed, scavenger concentrate and 1st cleaner tailing. Rougher con, 1st cleaner (sect ion 2) con and 2nd cleaner tailing are fed to 1st cleaners (section 1). 1st cleaner (section 1) concentrate and 3rd cleaner tailing serve as 2nd cleaner feed, while 2nd cleaner concentrate is fed to the 3rd cleaners which produce a final bulk concentrate. Table 1 lists cell types and specifications important to the circuit. DEVELOPMENT OF MODELS To develop flotation cell models a systematic procedure was employed (4). This involves the selection of responses and factors, proposing models to be fitted, the acquisition of raw data, the statistical adjustment of raw data, fitting models to adjusted data and testing the adequacy of fitted functions. Responses and Factors Responses of interest included recoveries, concentrate grades and concentrate solids/water flow rates for each stage. Factors that influence these responses, such as reagent addition rates, air flow rates to cells, solids and water flow rates to stages and feed grades were not manipulated during the sampling period. Thus, the investigation was limited,

Jan 1, 1986

By H. Beecher (Original by) Charmbury

Water is a most remarkable substance, essential for life of all kinds. As well as needing water to survive, man has always used it for agriculture, transportation, recreation, and many other things. When our country was young and inhabited by few people, the streams, rivers, and lakes were able to provide all the clean water needed by man and take away all the wastes created. However, with our growing population and an ever-increasing demand for goods and services, the public, industry, and government at all levels have become acutely aware of the need to manage the nation's water resources more efficiently. Abundant energy from many sources has helped this nation to become the greatest industrial nation in the world. Coal has contributed a major portion of this energy, generating electricity, running railroads, and maintaining national security during wartime. The result has been the highest standard of living in the world and a time of widespread economic prosperity. The use of water in coal mining is somewhat different from its use in most industries. With the exception of water used in cleaning plants, for underground dust control, and for fire protection, most of the water en- countered in coal mining operations serves no useful purpose. In other words, it is an undesirable element and must be removed, otherwise it will interfere with operations, cause potential water quality problems, and may even stop operations by flooding. In the past, removing water from working areas of most mines was usually a fairly simple matter. Pumps with piping were installed at sumps or low spots in the mine and the water was pumped to the surface or to drainage control facilities constructed for the operation. Ditches were often used to collect and drain the water by gravity to the outside or to main sumps for pump discharge. In either case, the water was allowed to flow into the nearest stream or river. The concept of "water is water' was generally accepted without too much concern for what was in the water since low-cost products and services, rather than clean water, were the public demand.

Jan 1, 1981