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By C. J. Bise

Safety training requirements differ from mine to mine due to changes in the demographic characteristics of the workers or changes in job and organizational characteristics. Accordingly, a microcomputer-based procedure has been developed to assist mine trainers is determining if undesired worksite performances result from lack of knowledge or skill, which are trainable categories, or from categories that are considered to be non-trainable (such as equipment limitations or management procedures). A special effort was made to understand the psychology of worker behavior by analyzing worker reactions to various organizational and job characteristics.

Jan 1, 1995

By M. Karmis, C. Haycocks

Geographic Information Systems (GIS) are becoming a more commonly used tool for resource estimation as they provide not only a database management platform, but also the graphical capabilities to visualize resource characteristics. Interpolation methods used commonly in these resource studies do not typically provide a quantitative answer to the question: "How accurate is the estimate?" By comparing localized measurements at several locations to the interpolated thickness distribution used in a resource estimate, a quantitative analysis of accuracy can be obtained. The technique is demonstrated with a case study from Central Appalachia.

Jan 1, 1999

By Trevor J. Smith, Kevork A. Chouzadjian, Rob S. Burns, Steve J. Roden, Michelle A. Spieth

Investigations were undertaken to improve the recovery of silver from CRA's Hidden Valley gold/silver deposit by the addition of calcium peroxide. The addition of 0.75 to 1.5 kg/mt of calcium peroxide improved silver extraction by 5 - 300 and reduced cyanide consumption by up to 30%. Gold extraction was also marginally improved in some of the tests. The results are of economic interest and plant trials will be initiated once operations are underway.

Jan 1, 1990

By J. K. Mudge, T. Allen, P. B. Johnson

Approximately 6 years ago, Newmont Mining Corporation (Newmont) initiated reclamation/closure at its’ Hollister operation in Nevada. Reclamation/closure challenges existed at three primary areas within the operation. One the open pits had a small, low pH lake. The primary waste rock dump had a collection system for seepage of low pH solution. The heap leach had a typical inventory of process solution. In each of these three areas water quality and water quantity challenges existed. Reclamation/closure techniques were employed that utilized run-on controls, re-sloping, capping/topsoil placement, pit backfilling and vegetation for water quantity control. Water quality controls included installation of passive, anaerobic systems. These mechanisms have effectively limited water volumes that require treatment and effectively treated the water to meet standards.

Jan 1, 2003

By Dennis K. Mortensen

Improvements in metallurgical performance are continually being made in the attempt to achieve the metallurgist's goal of maximum concentration, minimal loss of recovery and at costs that maximize profit margins. Innovative technological advances provide a means for the metallurgist to more thoroughly understand the mechanisms of separation and foster new ideas from old. Problems associated with the implementation of new technology can be overcome effectively if the metallurgist thoroughly understands the metallurgical systems with which he is working.

Jan 1, 1991

By Alfredo Romero Quispe, Carlos Hoffman Sampaio

This work presents a study of characterization of activated carbons for the adsorption of Au(CN)2- complex. A comparative study of six samples of activated carbons, three Brazilian and three produced out of Brazil was made in order to determine their qualification for a performance in adsorption circuits in the extractive metallurgy of gold. The adsorptive capacity and the kinetics of adsorption were compared to the physical and chemical properties of each one. The influence of poluant ions on the kinetics and loading capacity of aurocianyde anion was also determined.

Jan 1, 1995

By H. Peter Knudsen

In most open pit gold mines, ore-waste selection is based on estimates made from blasthole samples. These estimates frequently are biased. This paper focuses on the source of the conditional bias. While it is true that high grades and "outliers" can induce a bias, they may not be the only reason for the persistent bias seen at many mines. In this paper, it is shown that the poor blasthole sampling can cause a conditional bias in the estimates.

Jan 1, 1993

By L. Lichty

Treatment of refractory gold ores containing arsenic has always presented a major problem in their processing to recover the contained precious metal values. The major difficulties are concerned with lower recoveries and production of hazardous fumes, effluents and residues. Due to these arsenic related problems, many otherwise economically attractive precious metal deposits and dumps all over the world are not exploited. In recent years, treatment processes for refractory gold ores and concentrates have been explored. A few commercial operations employing roasting or pressure leaching have resulted. Roasting has limitations due to environmental constraints related to off gases. Pressure leaching involving high temperatures (180° to 200° C or 356° to 392° F) and pressures (2.75 MPa or 400 psi) is accompanied by high capital and operating costs.

Jan 1, 1990

By Michael E. Lively

DOUG HALBE: We've talked about copper operations and gold operations. For our third section on the topic "Operating Ideas That Have Saved Me Some Bucks," we'll turn to the coal fields. Our featured speaker is, I'm almost embarrassed to say, a mining engineer, Mike Lively. Mike has 25 years' experience in the coal industry. He is currently superintendent of surface operations for Southern Ohio Coal Company, Meigs Division (AEP Company). I've read his paper, and there's some really great information here. Mike.

Jan 1, 1998

By K. N. Han, X. Xie

The dissolution behavior of palladium powder in thiourea solutions was investigated. The variables studied were temperature, stirring speed and the concentrations of thiourea, acid and ferric ion. Palladium was found to be soluble in thiourea solutions in the presence of an oxidant such as ferric ion. The dissolution of palladium in thiourea solutions was believed to be chemical-reaction controlled, with an apparent activation energy of about 25.3 kJ/mol.

Jan 1, 1997

By G. Gaidajis

In this paper, a semi-qualitative methodology is presented and then applied to an aluminium extrusion industrial facility in order to perform an initial environmental assessment. The results of the assessment enable an improved understanding of the environmental performance of the facility and more importantly identify the areas of significant environmental concern. Following, the application of case-specific sustainability indicators related with the areas of significant environmental concern, leads to a more comprehensive sustainability assessment. The applied two-step approach offers a quick and reliable environmental assessment and help focusing on the most environmentally problematic areas. Moreover, the follow-up of the specific indicators seems to be appropriate for the improvement of the environmental performance of the examined industrial facility.

Jan 1, 2008

By J. B. Rubinstein, V. J. Badenicov, S. T. Hall

A simulation technique of the flotation process and models for the solution of various problems are developed. A modular model of column flotation is constructed taking into account the kinetic relationship of the process and the hydrodynamic regime in the cell. Based on this, a technique of calculating the column parameters based on laboratory tests is developed (scaling-up), and applied for calcetest results is developed (scaling-up), and applied for calculating the design of commercial-scale columns.

Jan 1, 1996

By G. Hilson

The exact application of sustainable development in the mining and minerals industry has precipitated considerable debate in recent years. Since the publication of the Brundtland Commission?s Report, Our Common Future, numerous attempts have been made to define sustainable development in the mining context. The inability of the Brundtland Report to outline an effective sustainability framework, combined with its contention that no single blueprint for sustainable development exists, has prompted many academics and practitioners to provide viewpoints on the application of sustainable development in the mining and minerals industry. This paper provides an overview of the many groups of assessments made of sustainable development in the mining industry. Sustainability assessment and reporting for this industry sector using indicators are also addressed.

Jan 1, 2003

By Thor Skjeggedal

The Norwegian contracting firm A/S Høyer-Ellefsen has for the last 2.5 years carried out substantial pregrouting in a 7600m long tunnel just outside the city of Oslo. This has been done to avoid groundwater lowering and consequent damage to surface structures. A WIRTH TBM is used in combination with a 2 boom Atlas Copco hydraulic jumbo for the drilling of groutholes in front of the machine. The detailed procedure for the drilling and grouting will be discussed, and the results obtained will be presented.

Jan 1, 1981

By J. M. Velazquez, J. H. Meza Viveros

This paper describes some of the parameters and technologies used at the Mexicana de Cobre smelter, and discusses the principal design parameters and new technologies that are being implemented in a smelter-expansion project designed to increase the production capacity of anode copper from 180 to 300 kt/year (200 to 330,000 stpy). In addition, some parallel projects under construction in the smelter plant are described.

Jan 1, 1999

By T. R. Ellis

The author is the leader of the Extractive Industries Task Force of the International Valuation Standards Committee. The Task Force has developed an Extractive Industries section for inclusion in the International Valuation Standards (IVS). The Extractive Industries Guidance Note provides comprehensive standards for valuation of all minerals and petroleum industry property types for all valuation/appraisal purposes. The document is scheduled for release as an exposure draft for public comment by December 2003, then it will be finalized for publication in the IVS in mid-2004. This paper discusses the content and philosophy of the Extractive Industries Guidance Note within the context of the framework of the IVS. It also discusses the international implications and implementation of this IVS addition.

Jan 1, 2004

By Håkan Stille, Kjeld Boye-Møller, Lars Lundström

BACKGROUND Forsmark Power Station is a nuclear power plant under construction at the Baltic abt 120 km north of Stockholm. Investigations on the Site were started in 1969. Areas were reserved for a maximum of 6 units of which the buildings for two of them, Unit 1 and 2, were nearly finished in 1976, when the investigation for Unit [3], here presented, was carried out, cf Fig. 1. [ ]

Jan 1, 1979

By Haydn H. Murray

A hydrothermal bentonite located in the high Sierras in Nevada is being mined and processed for use as a natural dietary supplement. Because hydrothermal clay deposits are normally zoned and not uniform in composition, a special stockpile was constructed to assure uniformity of processed products. The stockpile of clay was layered and rectangular in shape. Channel samples were taken from 10 locations around the stockpile and were mixed and quartered to provide representative samples. The samples were then chemically and mineralogically analyzed. The results showed excellent uniformity. The mineralogy and chemical analyses will be discussed in the paper.

Jan 1, 2005

By Lynn B. Hales, Randy A. Ynchausti

Expert supervisory control strategies have been used for many years to improve operating revenues in comminution circuits. Typical improvements in capacity range from four to eight percent. Several case studies of results will be presented as well as a general discussion of the technologies used to achieve the improvements. Crushing. SAG milling and ball milling circuits will be discussed.

Jan 1, 1997

By K. R. Johnejack, R. Quintanar, P. Lapointe

Chino Mines Company has investigated effects from historical mining to sediment along Hanover and Whitewater Creeks. Concentrations of metals were statistically stratified for risk assessment. Stratification by size was more prevalent than by depth, with concentrations higher in the fines. Concentrations with depth were mixed, but overbanks showed more stratification with higher concentrations in the surface. Members of a geomorphic feature type generally were not stratified. However, geomorphic features were stratified by type, with the active channel and bars being the most alike and the overbanks being the most different. Only a few metals showed decreasing concentrations with distance downstream.

Jan 1, 2002