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The 18th annual American Mining Hall of Fame Awards Banquet sponsored by the Mining Foundation of the Southwest will be held on Saturday, Dec. 2, 2000 at The Westin La Paloma in Tucson, AZ. The 2000 inductee, guest of honor and featured speaker at the banquet will be Ronald C. Cambre, chairman and chief executive officer of Newmont Mining. He will be honored for his role in positioning Newmont as an innovative and key player in the gold mining industry.

Jan 1, 2000

By M. S. Fraley

As we compete for close margins in wholesale sales, the effects of both quality and price have a major impact on the cost of producing electricity.SO2 emission allowances have traded as low as$60/ton to as high as $215/ton over the last three years. This price spread in emission allowances clearly demonstrates the correlation between the quality of fuels versus the price utilities will be willing to pay for them. This paper provides an overview of the effects of the qualities of fuel, coupled with transportation as well as environmental concerns on the price of fuel and the ability to compete in a deregulated electric market.

Jan 1, 2000

By A. A. Schweizer

This paper documents the growth and projects the future of Green Diamond Sand Products. Since1954, Green Diamond, located in Riddle, Oregon, has been producing sand from granulated nickel slag for use in various markets. Through the years, the company has seen several changes from its ownership to its product lines. In 1991, Green Diamond was producing abrasive sand at a rate of about 30,000 tons per year. It was at this time that Green Diamond became part of Glenbrook Nickel Company. Over the next eight years, Green Diamond would quadruple its production to over 140,000 tons while moving into three new markets, as well. Green Diamond is now producing sand for use in the abrasive, foundry, construction, and roofing industries. In 1998, Green Diamond again found itself under new, private ownership. With plans on developing agricultural sand and spent abrasives recycling, the future of Green Diamond appears to be one of further expansion coupled with diversification of its product lines.

Jan 1, 2000

By M. C. Roberts

Currently, mineral producers are suffering through a major downturn in prices for their products, even though it has only been a few years since they were enjoying high prices. From an historical perspective, the current situation is another of the cyclical down-turns that often reoccur every 5 to 7 years or so. This paper uses time trend decomposition techniques to identify the cycles and statistical methods to find the duration of these cycles for a variety of mineral prices. Given some idea of how long and severe these cycles typically are, the mining industry can better plan to weather the downturns and take advantage of the upturns. For example, timing investments in new projects to take advantage of the cyclical upturns can dramatically improve project profitability.

Jan 1, 2000

By Jasna Jurjovec, David W. Blowes, Carol J. Ptacek

At the Kidd Creek site, natrojarosite residue, derived from the zinc refinery circuit, is mixed with mill tailings before final disposal in the tailings impoundment. Column experiments were conducted with fresh unoxidized mill tailings and a mixture of tailings containing the natrojarosite residue. Acidic water, simulating mine drainage water, was pumped through the columns. The effluent water geochemistry was interpreted with the assistance of MINTEQA2. The experimental results suggest that the effluent water pH was buffered by a series of acid neutralization reactions. The release of metals, including Cu, Pb and Zn, was affected by pore water pH, Eh and mineralogy of the tailings material.

Jan 1, 2000

By Youning Li, William J. Drury, Christopher H. Gammons

A demonstration scale, subsurface flow anaerobic wetland was built to treat zinc and other metals in surface drainage near the historic mining center of Butte, MT. Based on three years of continuous monitoring (1996-1998), copper and cadmium were effectively removed year-round, but attenuation of dissolved zinc was dependent on hydraulic residence time (HRT) and bacterial sulfate reduction (BSR) rates. BSR rates decreased in winter months, as did HRT due to the development of thick frost zones in the substrates. An additional problem was the inability of the wetland substrate to completely filter out fine-grained particles of ZnS forming in the anaerobic cells.

Jan 1, 2000

By B. P. Sullivan

This paper describes how the author projected the economic benefits of a proposed coal liquefaction project based in Pennsylvania. These benefits were assessed in a successful effort to garner government support for the project. The projections considered such issues as increases in employment, wages, and tax receipts to state and local government, plus other less-obvious benefits, such as site remediation. The paper explains how sponsors of similar projects can use economic projections in making meaningful and compelling presentations to federal, state and local authorities.

Jan 1, 2000

By Diane Germain, Normand Tassé, Claude Dufour

At the East Sullivan site, pore-waters underlying a wood waste cover that prevents sulfide oxidation are characterized by an anoxic environment, abundance of dissolved organic substrates, and near neutral pHs. Such conditions favor sulfate reduction and base metals precipitation as sulfides, as well as carbonate-metal precipitation. Pore-water composition from 1992 to 1998 shows a significant Fe2+ decrease. Therefore, the restoration strategy of that site capitalizes on these alkaline and reductive properties. Since 1998, a novel treatment of acid effluents, based on the recirculation of water discharged around the impoundment through the organic cover, is tested on the site. Available data gathered in 1998 and 1999 shows that the pH of recirculated water flowing within the wood waste cover increases by 2 to 4 units and that Fe,, concentrations decrease by a factor greater than 6.

Jan 1, 2000

By Regina N. Tempel, Laurie S. Balistrieri, Lisa L. Stillings, Lisa A. Shevenell, Maggy F. Lengke

Dexter pit lake, within the townsite of Tuscarora, Nevada, has been in existence since 1990 and provides a natural laboratory for the study of cycles of trace elements associated with ore deposits (e.g. As, Cu, Pb, and Se). Our goal in this study is to develop and calibrate methods of geochemical modeling that may be applied to estimating the concentrations and fluxes of trace elements in pit lake systems. Our initial modeling work considers limnology, hydrology, wall rock mineralogy and geochemistry, benthic fluxes, and colloid composition. Results from our work may be useful in evaluating water quality in the arid West.

Jan 1, 2000

By Mark R. Stanton, Douglas B. Yager

Integration and synthesis of mine-site topography, geophysical, and geochemical data yields both two- dimensional and three-Amensional perspective models for the May Day mine located in the Cement Creek drainage near Silverton, Colorado. Induced polarization, geophysical data are spatially registered with geochemical data acquired from drill hole cuttings that are contoured m three-dimensional space, thereby permitting determination of the most metalliferous and sulfur rich zones of a waste pile. This spatial modeling application was developed to be a visually intuitive tool to aid in mine waste reclamation.

Jan 1, 2000

By Regina N. Tempel, Timothy E. Eastep, R. Craig Ford, Bryce R. Roming, Geoff Clothier, Maggy F. Lengke

The Climax Mine, near Leadville, Colorado treats acid drainage in a lime neutralization chemical treatment system. Chemical treatment has been successful in reducing the concentration of metals to below surface water discharge effluent limits, but lime usage has not been optimized. A geochemical modeling approach has been developed to increase the efficiency of lime neutralization. The modeling approach incorporates two steps: (1) calibration, and (2) calculation of amount of lime needed to increase pH and remove metals. Results of our work quantify the lime treatment process and improve our ability to predict overall water quality.

Jan 1, 2000

By M. Beus, S. Stewart, S. Iverson

Recent ore pass failures have underlined the need for improved designs, standards, structural monitoring methods and better hang-up prevention and removal techniques. Researchers at the Spokane Research Laboratory of the National Institute for Occupational Safety and Health (NIOSH) are investigating methods to improve safety during the transport of ore in ore passes. Design criteria and hang-up prevention and remediation strategies involve studies of the effects of static and dynamic ore and waste-rock loads on chutes, walls, gates and support structures. Particle flow analysis methods were used to simulate the response of various ore pass designs to a wide range of ore loading conditions. A full-scale mockup of actual ore pass and chute assemblies was duplicated and tested for load response. Data from a particle flow code and the mock-ups were compared Loads on an active ore pass chute were measured

Jan 1, 2000

By M. J. Lawrence

Independent natural resource Valuers are an essential link between miners and mineral explorers on the one hand and the finance industry on the other. Investors (and regulators) expect the mining and financial industries to be vigilant against the use of inappropriate methodology or use of illogical steps within the chosen valuation method. The Australian Corporations Law generally requires an Independent Expert Report to support mergers and takeovers (as well as for capital raising activities). The introduction of the VALMIN Code (1998) by The Australasian Institute of Mining as Metallurgy, has meant that such Reports, when prepared in compliance with it, are now much more comprehensible and reliable than before. This is because the key requirements of the Code are for transparency and materiality in the Technical Assessment and Valuation Reports prepared in connection with the transaction involved. Transparency is particularly important because it allows the reader to identify and understand the assumptions made to derive a value and to then form a view as to the reasonableness of the result. Even though many elements of resource asset valuation practice are undeniably subjective, there must be some basis of objective rationality to it. Where the reasoning is patently illogical or the inputs are chosen to achieve a particular result, the estimated value must be viewed as virtually worthless. Experience, qualifications, competence and repute are the hallmarks of a professional technical auditor and valuer.

Jan 1, 2000

By Pascale St-Germain, Michael Li, Lionel J. J. Catalan

The oxygen flux into water-covered reactive sulphidic tailings is required for evaluating the long-term performance and predicting the quality of engineered shallow water covers. This information can also serve as an input to the design of water covers for reactive tailings decommissioning. This paper describes some dissolved oxygen (DO) profiles recently measured in the field across the tailings/water interface and oxygen fluxes derived from these profiles. These fluxes are compared with previously reported flux values from similar field measurements. Techniques and pitfalls for measuring DO profiles and calculating oxygen fluxes are also discussed.

Jan 1, 2000

By Mary Ann Harrington Baker, John Trudnowski, Marietta Canty, Marek Zaluski

Three Sulfate-Reducing Bacteria (SRB) passive field-bioreactors were constructed at an abandoned mine site near Butte, Montana, to mitigate AMD emanating from a waste rock pile. Each SRB field-bioreactor contains chambers of an organic source, limestone, and cobbles. The field-bioreactors are configured differently to test the effect of different environmental conditions on the SRB. Preliminary observations indicate that, during start up and the first eight months of operation, the quantity of organic carbon supply significantly impacts the SRB activity. To date, the dissolved metals have been reduced significantly and the pH has increased.

Jan 1, 2000

By J. A. Organiscak

Two types of airflow splitting methods for improving longwall dust control were investigated by the National Institute for Occupational Safety and Health's Pittsburgh Research Laboratory. Investigated were a translucent mesh barrier and a staged spray barrier system to confine the shearer-generated dust to the coal-extraction side of the longwall face while maintaining a cleaner split of airflow on the opposing worker walkway side of the longwall face. In laboratory experiments and in a longwall field evaluation, the translucent mesh barrier was shown to provide notable dust-control effectiveness for a distance of up to 60 m downstream of the shearer, provided that the mesh barrier remained relatively parallel to the airflow. The staged spray barrier system showed marginal dust-control effectiveness in the laboratory and, therefore, was not field tested.

Jan 1, 2000

By Paul G. Greenhill

The Australian Mineral Industries Research Association (AMIRA) was established by the Australian mineral industry in 1959 to develop and manage collaboratively funded research projects. Owned and managed by industry, it coordinates research that answers questions defined by the sponsoring companies of the projects. Now over 35 years old, the Association is an excellent example of what can be achieved through collaborative research and an industry - backed research organisation.

Jan 1, 2000

By Roger B. Jr. Herbert

Surface water samples were collected from water accumulations at the surface of a neutral pH mine tailings deposit in Kristineberg (Sweden) where algal growth and iron hydroxide precipitates were observed. Ferric iron in the aqueous samples was determined by (adsorptive) differential pulse - cathodic stripping voltammetry. The analyses indicated that labile Fe3+ concentrations were in the range <20 to 337 nM, while total Fe3+ levels were much higher at 0.9 to 8.3 uM. The labile Fe3+ levels are more than two orders of magnitude greater than would be expected based on equilibrium with ferrihydrite. These results suggest that iron complexation with strong ligands in the surface water competes with iron hydrolysis, and that these ligands may be of algal and/or bacterial origin.

Jan 1, 2000

By R. A. Kirkland

The oxygen consumption method utilises an oxygen sensor to monitor the gas-phase oxygen concentrations in sealed chambers filled with reactive waste rock with subsequent confirmation of the oxygen content by gas chromatography. Results of experiments utilising low sulphide (<0.5w1%) waste rock yielded reproducible oxygen consumption rates on the order of 10-10 mol O2.kg-1. s-1. Petrographic analysis of the waste rock material indicated that the dominant sulphide mineral is pyrite (FeS2). Assuming a stoichiometry of 1.75 moles of O2 per mole of SO4 sulphate release rates were inferred to be between 6 and 18 mg SO4 kg-1 wk-1 Typically these results are 2 to 3 times greater than measured sulphate release rates from humidity cells. Our findings suggest that this techniques offers a rapid. cost efficient method for determining sulphate release rates in waste rock piles, even at low sulphide concentrations.

Jan 1, 2000

By E. Hughes, D. Akers, D. Stopek

The Upgraded Coal Interest Group (UCIG), focuses on clean, low-cost options for coal-based power generation via pre-combustion, co-firing and reburn options. Its mission is to preserve and expand the economic use of coal for energy. By reducing the fuel costs and environmental impacts of coal-fired power generation, existing units become more cost effective and thus new units utilizing advanced combustion technologies are more likely to be coal-fired. Two great forces are reshaping the power generation industry, the Clean Air Act Amendment and deregulation of generation. The Clean Air Act Amendment is forcing change by making it necessary for power producers to plan for reducing emissions of sulfur and nitrogen oxides and possibly trace elements. At the same time, deregulation of generation is forcing utilities to focus their attention closely on the short term impact of any change on cost of power. Fuel is a utility&apos;s largest cost element; maximum fuel flexibility will be a utility&apos;s best weapon in an environment of rapid change. In a regulated environment, a utility was limited in how involved he might get into fuel supply, in a purely deregulated environment he need only be guided by the impact on the bottom line. It is clear that these two forces will promote a close look at factors such as coal upgrading which can have an impact on the availability of low sulfur coal or emission of NOX and trace elements.

Jan 1, 2000