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By R. H. King

The Deserado Mine of Western Fuels- Utah Inc. installed a micro-computer based mine wide monitoring and control system for mine environment, beltway fire protection, belt operating parameters, and equipment power utilization. The Colorado School of Mines was funded by the U.S. Bureau of Mines to document, evaluate, and report on the system design, procurement, installation, tests, and operation. This paper results from that project. The paper compares planned activities such as installation and start up, procurement contract specifications and system layout with actual performance to develop recommendations for future installations by mine operators.

Jan 1, 1987

By T. Harris

Exports of crude gypsum from Mexico currently comprise about 60% of all domestic shipments, and about 25% of the imported material consumed in the U.S. wallboard industry. However, of growing importance are the domestic markets for calcined gypsum in Mexico including building plasters and wallboard, which account for 55% of the internal demand for natural mined material. This paper will examine the current trends in the production and trade of natural mined gypsum in Mexico and North America and the opportunities and threats that are facing existing and new suppliers in this changing market.

Jan 1, 1996

By D. J. Fitzpatrick

The paper reviews current mining subsidence research at The Department of Mining Engineering, University of Notting- ham. Special attention is being devoted to prediction of ground movements between the mining horizon and the surface using physical and computer-based models. The paper presented discusses linear and non- linear finite element methods and compares results with those from physical models and field observations. Special attention is focussed on the determination of the effect of caved zones on overlying and underlying geological structures. The paper presents data from comparisons with U.K. case histories.

Jan 1, 1986

By J. M. Pugliese

The U.S. Bureau of Mines is developing designs and estimating costs for vertical in situ copper mining wells as part of its in situ mining research program. Conceptual designs and estimated costs for "deep" 1100 m (3600 ft) recovery and injection wells in an undisturbed copper ore zone are presented. Within a single in situ copper mining well, multiple perforated well completions and associated costs are discussed for two ore zones between depths of 370 m (1200 ft) and 550 m (1800 ft). The order of well specifications for designing these wells is explained.

Jan 1, 1995

By W. H. Langer

The U.S. Geological Survey (USGS) in cooperation with the New Mexico Bureau of Mines is conducting an assessment of mineral resources in the 36,800 km2 Mimbres Resource Area, southwestern New Mexico. Included in the assessment is a literature-based evaluation of sand and gravel that utilizes third party geologic information. The USGS has developed a method based on existing 1:500,000 scale geologic maps supplemented by remote sensing, statistical models, and point data such as test hole or pit records. The method defines the areal extent, quality, and quantity of aggregate.

Jan 1, 1996

By J. Andrew Leach, Robert T. Tape, Thomas G. Harper

A practical approach to elope stability design of heap leaches up to 90 m (300 ft) high is presented based on recent experiences with heaps throughout the Western U.S. Shear strength parameters for foundations, ore and liner systems are considered, with particular attention given to frictional contacts between geomembranes and clay or geotextiles. Stability of both ore and containment dikes is discussed including the effects of seismicity, staged dike construction, progressive heap development and in-heap solution levels. Design criteria and methods of analyses are presented along with techniques for improving stability.

Jan 1, 1987

By H. T. Miller, L. M. Scott

Radiation exposures in Uranium operations may result from external beta-gamma radiation emitted by Uranium and its progeny, internal exposure to alpha and beta radiation due to the inhalation and ingestion of Uranium ores, Radon gas, and Radon progeny in mine, mill, and laboratory atmospheres and from the contamination of environmental working surfaces and clothing by Uranium-bearing compounds and ore. This paper summarizes occupational experience with reference to the exploration, surface mining, underground mining, milling and transport of Uranium by one company in the U.S. and Canada.

Jan 1, 1981

Maptek I-Site laser scanning expertise and software technology is being used to map the geology and layout of the deepest underground laboratory to be established in the U.S. The Deep Underground Science and Engineering Lab (DUSEL) in the former Homestake gold mine in Lead, SD, will provide for scientific studies in particle and nuclear physics, geology, hydrology, geo-engineering, biology and biochemistry. The project, funded by the National Science Foun¬dation (NSF), will allow geoscientists and engineers to research the behavior of subsurface rock, minerals, water and energy sources

Jan 1, 2010

By J. A. Burger

Research in the eastern U.S. has shown that productive mine soils and forests can be restored using the following guidelines: (1) cooperation among the mine operator, landowner, and regulatory authority in developing the mining permit; (2) replacing topsoil or creating a desirable medium in which trees are planted; (3) loosely grading non-compacted topsoil; (4) using native and non-competitive domestic ground covers that quickly protect the site; and (5) planting a proper silvicultural mix of crop trees for their commercial value along with nurse trees for wildlife and soil improvement.

Jan 1, 2002

By Thomas W. Camm

The U.S. Bureau of Mines has extensive experience estimating the cost of mining and mineral processing operations as an ongoing part of its information and analysis studies. With the increased interest in remediation of mine wastes, the USBM is developing a methodology to expand its cost estimating expertise to include costs of various remediation techniques applicable to mineral processing and mining wastes. By integrating waste remediation costs with existing USBM cost estimating systems for mine and mill operations, a comprehensive system for cost engineering studies will be developed.

Jan 1, 1995

By Joseph Peterson, Alexander May

The Bureau of Mines used geochemical modelling computer programs to characterize a site containing lead slag generated by a lead processing facility. Tests for toxic elements by the U. S. Environmental Protection Agency (EPA) extraction procedure showed that all elements except lead were in compliance. Concentrations for lead ranged from 28 to 30 ppm. However, analysis of water samples from monitoring wells resulted in no lead concentrations that exceeded the National Drinking Water Standard. A discussion of a computational program to calculate concentrations of lead species and several other ions is presented.

Jan 1, 1991

By F. E. Kottlowski

Widespread high-calcium limestones in New Mexico region are low -in magnesium, but some units include shale interbeds deleterious for sulfur removal usage. Thick limestones in Mississippian Escabrosa, Lake Valley, and Leadville, Pennsylvanian Madera and Hermosa, Pennsylvanian-Permian Horquilla, Permian Hueco and Capitan, Cretaceous U-Bar, and some Cenozoic travertines are high-calcium units. Significant outcrops are in mountains of southwestern, south-central, central, southeastern and north-central New Mexico, southeastern Arizona, southwestern Colorado, and northwestern Chihuahua. Coal-fired powerplants are mainly in northwestern New Mexico and eastern Arizona, thus transport is mainly by railroad.

Jan 1, 1994

By D. A. Harman

The U.S. Environmental Protection Agency recently recognized Newmont and other mining companies, along with the Nevada Division of Environmental Protection for their voluntary work in reducing mercury air emissions. One example of this voluntary effort is the installation of a reactive scrubber to capture mercury vapor from the exhaust of a carbon regeneration kiln at Newmont’s Twin Creeks Mine. After considering the available technologies, a proprietary reactive scrubber, developed by ADA Technologies, Inc., was selected and is currently being commissioned. Mercury removal rates greater than 90% have been documented.

Jan 1, 2004

By T. Kelly

The post-apartheid South African government has instituted a new minerals policy. As part of the new policy, minerals rights are now held by the national government, not as private property. In addition, the national government desires to see a greater participation of all South Africans in the corporate mining arena. At the same time, the national government has adopted a policy of a strong monetary unit compared to the U.S. Dollar. The combination of these tow policies has led to changes within the platinum mining industry.

Jan 1, 2004

By D. R. Taylor, R. G. Goss

The use of clay granules as carriers for pesticides dates from the early 1940's and by the present day represents a business conservatively estimated at between 200 - 300 thousand tons / year in the U.S. alone. Aside from economic and specific target pest efficacy advantages, the use of clay granules as pesticide carriers also delivers a number of environmental benefits which will be reviewed. Topics to be discussed will include: 1) drift control (versus liquid sprays), 2) mobility (in the environment), 3) worker safety, and 4) transportation (spill) safety.

Jan 1, 1999

By M. Quamrul Ahsan, Andrew Griffiths, Edward P. Jucevic

Heap leaching of precious metal ores using the cyanide process is extensively used in the Western U.S.A. for extracting gold. Consequently, the impact of cyanide in the spent heap is closely examined by environmental agencies and permitting authorities. Currently, many states require that all decomnissioned heaps be detoxified before abandonment. This paper describes a case study for detoxification of spent heaps at the ACH-Dayton Project using hydrogen peroxide. The chemistry of cyanide detoxification by hydrogen peroxide, together with simplicity of a detoxification operation, is discussed.

Jan 1, 1989

By J. H. Meza Viveros

This paper describes some actual parameters and technologies used at Mexicana de Cobre Smelter, and the principal design parameters and new technologies which wiil be used with the smelter expansion project, in order to increase the production capacity of anode copper from 180 000 mtpy to 300 000 mtpy. Likewise its describe some parallel projects under construction also in the smelter plant.

Jan 1, 1997

By M. Z. Rashad

The purpose of this work is to determine the influence of sample length or size on the value of variance (Semivariogram) to select the suitable length that is required to the geostatistical computations of ore evaluation. Three cases in Ghorabi Iron Ore were studied. The first one was on the iron fraction (Fe%) at which the semivariogram gave an evidence to good continuity of the fraction in the ore. In this case, the length of sample has not important influence. The second case was for the Mn% component of the same area where the semivariogram has a nugget effect. The selected length for this case was 4 meters. The Cl% fraction of the ore was the third case where the anisotropic phenomena was appeared and the suitable length is 3 meters.

Jan 1, 1992

By Lawrence P. Kennedy

The Lynne deposit is a volcanic-to volcaniclastic-hosted, Zn-Pb-Cu-Ag orebody located in the early Proterozoic magmatic terrain of northern Wisconsin. As of February 1991, core drilling has partially delineated a multi-million ton, near-surface, disseminated to massive sulfide deposit. The deposit is hosted by a gently dipping sequence of fragmental rhyolites, felsic tuffs, less abundant dacite to andesite flows, and fine-grained volcanic sediments. The deposit is broadly conformable With the host rock stratigraphy, but the ore zones thicken and coalesce in the central part of the deposit.

Jan 1, 1991

By G. Biles

The Eskay Creek Mine, a high-grade gold and silver underground mine in northwestern British Columbia started operations in late 1994. For the first three years of operation, ore was crushed to minus 2 inch; blended to satisfy smelter terms and direct shipped to smelters in Japan and Canada. Before commencing the above operations, preliminary evaluations had indicated that an extremely complex metallurgical facility, requiring a large capital investment, would be required to recover the precious and other economic metals. Subsequently markets for raw ore were identified and underground mining and ore transportation operations, at a nominal production rate of 300 tonnes per day, were commenced. Exploration diamond drilling in 1995 and 1996 discovered additional lower grade mineralized zones, which are less economic or uneconomic as direct shipping ore. Testwork demonstrated that these lower grade zones could be upgraded to marketable concentrates in a simple flotation mill. The mill was built in 1997 and has been in operation since late 1997. The mining rate now has increased to 400 tonnes per day including 250 tonnes per day of the direct shipping ore and ISO tonnes per day of the mill ore. Prime Resources Group Inc. wholly owns the Eskay Creek Mine. Homestake Canada Inc. owns 50.6% of Prime's shares and manages and operates the mine on Prime's behalf. This paper discusses the mining and milling operations as well as ore shipment and smelter contracts' administration.

Jan 1, 1999