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By J. G. Nalven, J. A. Sturgess

On July 1, 1999, most domestic metal mines will have to report releases of toxic chemicals into the environment for the first time as required by SARA Title 313. Some of these reportable releases will appear huge in relation to reports by other industries. The reasons for the potentially large reportable releases, special considerations for mining operations, and strategies for dealing with the reports are described. Data composited from experience with several mining companies is presented in the context of a typical goldmine.

Jan 1, 1999

By H. Benedict

For many years, asphaltic lubricants have been used on large open gears. The asphaltic's diluent is essential to thin the lubricant enough to be sprayed. Once the lubricant has been sprayed into place, the diluent evaporates, leaving the asphaltic to lubricate mating surfaces. Recently, this thinner has been changed to non-cancer causing diluents. The gain in safety corresponded to a lesser ability to evaporate. This paper explores how much diluent remains in the lubricant when it has been assumed to be flashing off. Having quantified the diluent in the lubricant, we can then estimate the effect this has on viscosity.

Jan 1, 2003

By L. Mao, R. Yoon

The thin film balance (TFB) technique was used to measure the equilibrium thicknesses of the water films formed between two oil phases. The measurements were conducted with dodecane at varying concentrations of dodecylammonium chloride, pH, and electrolyte concentration. The data obtained in the present work were used to calculate the surface forces acting between the two oil phases. The calculation was carried using the Extended-DLVO theory with the surface potentials calculated from the Gibbs adsorption isotherm. The results show that oil droplets suspended in water are hydrophobic and the hydrophobicity changes with surfactant and electrolyte concentrations.

Jan 1, 2004

By Shijie Wang

The metals of value in tetrahedrite are copper, antimony and silver. A new hydrometallurgical process is proposed to recover these metals from tetrahedrite. The process consists of leaching concentrate with ferric fluoborate, solvent extraction, electrowinning and residue treatment. Products from this process are high-purity SX-EW copper and antimony and a high-grade silver residue that will be further treated in a hydrometallurgical process for early release of silver. The process has advantages, such as achieving rapid leaching rates at modest temperatures with high metal recovery. Most pyrite is not attacked. Thus, it remains in the leach residue along with elemental sulfur.

Jan 1, 2003

The objective of this international conference was to assist the mining and minerals industries in their global transition to sustainable development. The main theme of the meeting, therefore, was the development, monitoring and assessment of sustainable development criteria for mineral operations. Emerging technologies that can assist in the development of criteria and performance measurements were also presented at the meeting. A goal of the conference was also to conclude with a consensus plan and a process, representing a variety of stakeholders, which can provide guidance to the global minerals community on the path to sustainable development. A number of papers were not submitted in time to be included in the printed proceedings. Hence this addendum was compiled and includes last minute paper submissions. The pages of this addendum are numbered consecutively to the main volume of proceedings, so that when a reference is made to a paper, a proper page number may be quoted.

Jan 1, 2003

By Kevin R. Burns, William A. Depree, John J. Jansky

This paper presents some of the work associated with the reduction of employee exposure to diesel and blasting contaminants at an underground salt mine. The purpose of the paper is to outline the procedures recommended in resolving the problems associated with these contaminants. The first stage consists of a complete mine ventilation survey. The purpose of the survey is to identify any problems in the mine. The survey consists of air quality, air quality and ventilating pressure measurements taken throughout the mine. After completing the survey, the information is analyzed to identify problem areas and the possible causes. All available solutions to reduce the levels of contaminants are then explored and evaluated for feasibility. The PSU Mine Ventilation Simulator is then used to accurately simulate possible changes to the ventilation system. These ventilation projections are a useful tool to illustrate to the company and union personnel the possible benefits of various ventilation changes. This paper will illustrate the phases involved in making important and sometimes expensive ventilation decisions. Through the cooperative efforts of MSHA, company and union personnel, the levels of contaminants have been reduced by approximately 200 percent. As a result of these ventilation improvements, the company can now safely increase production approximately 25 percent.

Jan 1, 1987

By Raphael Mourad, Colin R. Phillips

Fluorescence, radioluminescence, phosphorescence and thermoluminescence in TLD 100 and 700 are discussed and compared. The energy budget in thermoluminescent material is presented in general terms. Results of measurements of radioluminescence, phosphorescence and thermoluminescence in LiF:Mg irradiated with [a] radiation, using simple facilities, are presented. The calculated energy budget in the exposed chips using [a] radiation is compared to published data using [y] irradiation.

Jan 1, 1981

By Marvin A. Ph. D. Friedman

The following paper describes an overview of evaluations for assessing the potential hazards associated with handling newly developed reagents used in the mining industry. Important factors in determining the risk and hazard associated with handling a particular chemical include hazard identification, dose-response assessment, exposure assessment, and risk characterization. The hazard evaluation step involves collecting and evaluating appropriate toxicology information on a chemical. This can include a comparison of the structure of a developmental chemical with that of a material with known toxicology information. Acute toxicology data, including oral, inhalation, and dermal LD50 values, eye and skin irritation data and sensitization or allergic potential information are typically generated for new chemicals. Environmental and in-vitro genetic toxicology data (e.g. Ames test) are also used to evaluate new mining reagents.

Jan 1, 1994

By P. van der Veen

There are two key reasons for this presentation: - Sustainability - Improving the economic, environmental and social impact of mining. As I will discuss in my presentation we see sustainability throughout the mine life cycle as critical for successful mine development - that is the mine makes a successful contribution to economic development and poverty alleviation for the host community and host country and at the same time the mine is a successful investment for the investor. - Knowledge Sharing ? The World Bank is not only a development bank, but also a ?knowledge bank?. One of our key functions is the dissemination of usable information and knowledge. We are here not only to share our experience but to learn from your experience as well ? two reasons that fit clearly with the mandate of the World Bank Group.

Jan 1, 2003

By D. F. Martin

Sustainability is typically understood as having three interrelated dimensions-environmental, economic, and social. However, far less attention has been paid to social sustainability than to the other two forms. The paper argues that one of the difficulties in giving substance to the concept of social sustainability is that it is inherently value-dependent and has major conceptual, definitional and therefore measurement issues. This is particularly the case in complex crosscultural environments such as those found in Australian mine hinterlands with significant Aboriginal populations. Nonetheless, a concept of social sustainability can provide an important counter to the usual focus on environmental and economic sustainability, and can productively guide the minerals industry in its engagement with the Aboriginal people of mine hinterlands. The paper outlines a set of principles for socially sustainable communities, and proposes means by which these principles can be implemented. It further suggests that these principles may have broader applicability than just in the case of Aboriginal people.

Jan 1, 2005

By L. Landryova

The Department of Control Systems and Instrumentation, VSB - the Technical University Ostrava, has been involved in a project dealing with utilization of landfill gases, when the methane gas utilization and minimization of its release into the atmosphere was the main concern. The landfill site is generally a place, where technology for energy production can be built. The conditions for this technology implementation vary and depend on various factors. This paper is presenting findings and experience gained regarding a method of methane gas utilization for energy production. This method is concerning building bioreactors at the landfill sites, which are already operated. Every bioreactor can be thought of as a process, which is controlled in order to maximize energy production and minimize the methane gas escape into the atmosphere. The bioreactor landfill can represent a number of environmental and cost savings and, at the same time, is able to comply with all legislative issues.

Jan 1, 2005

By E. G. Joe

Introduction Uranium mining has been actively carried on in Canada for over twenty-five years mainly in Ontario at Elliot Lake in Bancroft, and in Northern Saskatchewan at the operations of Eldorado Nuclear Ltd. During this period, approximately one hundred million tons of mill tailings have been created and lie mainly on the surface close to the mining and milling installations. If all of the present reserves of uranium ores in Canada are mined, a further eight hundred million tons of mine tailings could be created in Ontario, Saskatchewan, the Northwest Territories, Labrador and British Columbia. The present control of effluents from existing tailings is managed by the operating mines under the regulations of both federal and provincial control agencies. It is the long-term effect of these tailings on the environment that has not been clearly defined or measured. Several years ago, the Canada Centre for Mineral and Energy Technology of the Department of Energy, Mines and Resources, embarked upon a program of research directed at the long-term effects of uranium mine tailings. Much of the research to date has been on tailings in the Elliot Lake, Ontario area where some tailings piles have existed for over twenty years. The program consists of two projects, one to address the problem of existing tailings and the other to examine alternatives in the management of current and future tailings. TAILINGS CHARACTERISTICS Uranium tailings are generally the result of sulphuric acid leaching in which the uranium and alkaline minerals such as carbonates and chlorites are leached out. If the ore contains sulphides, these minerals potentially present an additional hazard of acid generation over time and could increase the mobility of heavy metals and some radionuclides such as thorium-230. Except for the extracted uranium, most of the radionuclides from the ore remain in the tailings pile. Uranium ores in Canada span a wide variety of mineralization and associated gangue composition. Uranium minerals include pitchblende, uraninite, uranothorite, brannerite and the phosphate uranium minerals autunite and saleeite. Gangue minerals vary from acid consuming carbonates, and chlorites to acid producing sulphides and inert silicates. With such a wide variety in ore composition, the characteristics of the resultant tailings in Canada are in many cases site specific and the solutions to the long-term effects of these tailings may also be site specific.

Jan 1, 1980

By R. C. Dunne, C. T. O'Connor

Flotation practice on eighteen South African flotation plants is described. The plants are categorized as those treating reclaimed tailings, those treating material which has already been subjected to cyanidation or uranium leaching, and those treating milled ore. The similarities and differences are highlighted.

Jan 1, 1998

By Henry A. Russell

During the last ten years Parsons Brinckerhoff has become a leader in the area of tunnel rehabilitation. A significant part of any tunnel rehabilitation program is the control of groundwater infiltration into the structure. This leakage over time, causes deterioration of the structures, and creates numerous operational problems for the tunnel operator. This paper will address current procedures for identification, documentation, and recommendations of repair methods for the control of groundwater infiltration in rail and highway tunnels.

Jan 1, 1993

By Christopher J. Hall

This paper describes the results from computer runs simulating 24 different mine ventilation configurations with the main fan situated first at the top of the upcast shaft and then at the top of the downcast shaft. Real air was used, with evaporation, condensation and heat exchange. The results showed that power requirements for the forcing fan were up to 20% less than for the exhausting fan for equal mass flow rates.

Jan 1, 1989

By D. W. Fuerstenau

Experiments using an optically polished Pyrex disk and aqueous dodecylammonium acetate (DAA) films showed that the velocity with which the films recede increases markedly if the runs are repeated at short time intervals, where equilibrium cannot be reattained. This results from DAA molecules being desorbed from the disappearing liquid-air interface and being deposited on the solid-air interface being formed. Controlled experiments with Pyrex particles in a modified Hallimond tube showed a similar increase in flotation rate, again due to excess adsorption of DAA molecules that were transferred to the solid-air interface from the bubble on contact.

Jan 1, 2002

By Michael T. Ballard

The key to productive computer usage is system software integration with full compatibility among individual components. The majority of software developers in our industry are still in the process of perfecting individual components. As a result, exchange and validation of data between disciplines becomes an arduous process. We at Morrison Knudsen Engineers, Inc. (MKE) have integrated an entire system, allowing exploration, geology, modeling, mine planning, and operation modules to work as a single, complete system with direct exchange and validation of data. The importance of integration to both developers and users of today's mining soft- ware is becoming increasingly apparent as we, an industry, move toward growth and enhancement of the technology of ore reserve acquisition, evaluation, and management. It is also important to understand the present state of integration and where it is leading US. Not long ago, another industry passed through the same stages we are now setting up for the mining industry. The stereo industry began with a few individual components, the record player, tape recorder, and radio. People were able to play records, listen to the radio and record conversations and music only through microphones on their tape recorders. Soon, one enterprising individual discovered he could tape sound directly from the radio or record player by capturing audio output from the speaker wires. Interfaces and patch cords were developed, providing a means to transfer audio information between components with not only little loss of sound quality, but also the elimination of back- ground noise. The industry took another step forward with the introduction of "integrated" stereo, where the components were packaged in one cabinet with shared resources. This reduced overall cost which paved the way for better quality. Today's stereos are now so well integrated that many of the components share data and resources from the same manufacturer, designed to work together for almost perfect data transfer between any of the components. The result is better sound, convenience, and reduced cost. This is the ultimate goal for integration. Any system development passes through these same steps on the road to total interaction. Initially, the components are designed, tested, and marketed individually, often by separate companies. As the users become familiar with the components, the need arises for an automatic interface between the components. This is necessary to cut down on error during data transfer and to eliminate the redundant work required to enter results from one component into the next component in the system. As a result, interfaces must then be developed to aid in this data transfer. After data transfer is accomplished, the next step is resource sharing. Resource sharing is careful design and engineering by either cooperative, individual manufacturers or one firm taking on the task to produce a single package product. Design and resource sharing leads to lower overall cost, while still providing component capability with options to grow as the user grows. The mining software industry has been working to develop some very high quality component software and has indeed accomplished this task in every aspect of the mining industry. However, realizing the importance of integration, some companies with limited individual resources have started working together to interface their individual components. Other firms have undertaken the project of developing complete, integrated systems.

Jan 1, 1987

By C. Botha, M. J. Walls, C. T. O'Connor

The role of copper sulphate in the flotation of pyrite has been studied. A survey of a number of pyrite flotation plants using copper sulphate showed that in correct dosages, it was able to increase both grades and recoveries. This was confirmed in batch tests. Copper sulphate had no significant effect on the rate of adsorption of PNBX onto pyrite. Copper adsorbed irreversibly onto the pyrite when the latter was slurried in a copper sulphate solution. Copper sulphate had a significant effect on the maximum froth height obtained in static three-phase froth tests. Proposals to explain these observations are made.

Jan 1, 1998

By Bob Clayton, David Readett

Jameson Cell technology has found applications in the cleaning of entrained material in copper Solvent Extraction - Electrowin plants. The materials involved are largely organic substances that have not been totally removed prior to treatment of the rich electrolyte in the tank house. This paper discusses the recovery of the entrained organics in the rich electrolyte streams at Phelps Dodge Morenci in Arizona. Mount Isa Mines in Queensland. Australia and the Olympic Dam Operations in South Australia. The paper details the design, performance, the feed and product characteristics, capacity and operation. In one operation the entrained material has been observed to include crud that has been formed in the SX train. The mechanism of recovery is also discussed.

Jan 1, 1993

By S. G. Axen

Design of wells for in-situ leaching is based on individual mining operation and ore deposit requirements. Major design considerations are well flowrate, depth, fluid composition, expected well life, mine operating plan and cost. A large variety of downhole equipment, materials of construction, contract services and methods of well completion and stimulation are available. A generalized design procedure which allows the engineer to optimize well design for a particular ISL application is described.

Jan 1, 1988