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By Steve J. Czehura

The Butte quartz monzonite is the host rock for early porphyry copper style mineralization and subsequent mesothermal-epithermal, enargite-gold style veining that transects the district. The east-west Anaconda system veins sustained mining for over a century. They include the Emma, Anaconda-Original, Syndicate, Badger-State and Alice-Rainbow veins, each with strike lengths of more than 3,660-m (12,000-ft) and vertical continuity in excess of 1,370-m (4,500-ft) with mining widths from 1.5- to 15-m (5- to 50-ft). These characteristics are unique to Butte. The incredible dimensions and tenor of these veins have yet to be surpassed and Butte is still touted as being the “Richest Hill on Earth.” The Anaconda Company was formed in 1895 to develop underground copper reserves in the district. It eventually consolidated all operations under one company. Production from underground mining continued through the mid-1970s. Openpit mining in the Berkeley pit began in 1955 with the extraction of supergene ores, along with the remnants of deeper horsetail zones inaccessible to the underground mines.

Jan 1, 2006

By T. Celik, B. Genc, C. Musingwini

"Mine planning software continues to be an important factor when it comes to the development of the South African mining industry. To contribute to this development, a new methodology to define and measure mine planning software utilization in the South African coal mining sector within an evolving data-set framework was developed. An initial data-set showing the mine planning software providers, their corresponding software solutions, as well as the software capabilities and information on the number of licences was collected and compiled in 2012 in an online database for software utilized in the South African mining industry. Details of the database development and implementation were published in the Journal of the Southern African Institute of Mining and Metallurgy in 2013. In 2014 the data-set was updated with additional and new information.In this paper, using the 2012 and 2014 time-stamps, a methodology for estimating the software utilization is developed. In this methodology, three variables: commodity, functionality, and time factor are used to define and measure the software utilization in order to ultimately inform decision making strategies for software utilization. Utilization in the coal sector was measured according to six different functionalities, namely Geological Data Management, Geological Modelling and Resource Estimation, Design and Layout, Scheduling, Financial Valuation and Optimization. The methodology is useful for stakeholders reviewing existing software combinations or intending to purchase new software in the near future and wanting to estimate the comparative attractiveness of a certain software package. These stakeholders include mining companies, consulting companies, educational institutions, and software providers. The work presented in this paper is part of a PhD research study in the School of Mining Engineering at the University of the Witwatersrand."

Jan 1, 2016

By G. L. Mowrey

One critical element of the U.S. Bureau of Mines (Bureau) autonomous mining research program is the development of a reliable coal interface detection (CID) system. Several candidate CID concepts currently being investigated by the Bureau include vibration, passive infrared, radar, and natural gamma radiation (NGR). To establish which CID sensor technologies need to be developed for a given seam, coal and adjacent rock samples (i.e., immediate roof and floor) are being collected from selected major coal seams in the U.S. and are being analyzed in terms of NGR and other geophysical measurements. Results of the NGR measurements indicate that, in general, all shale and shale-like materials (e.g., drawslate, slate, and fireclay) have higher NGR readings than the coal seam. Consequently the NGR method appears to be a potentially useful CID tool, provided that the immediate roof and floor are both composed of a high percentage of shale-type material.

Jan 1, 1990

By James M. Link

Slurry transport of industrial minerals has proven to be practical, economical, and efficient. Industrial minerals currently being pumped for long distances include cement, clay, phosphate, sand, and various waste product from industrial mineral processing operations. This paper will touch upon the basic theory of hydraulic transport of solids and then consider the economic and engineering considerations upon which construction and operation of such a line would be based. Where possible, actual cost data will be presented.

Jan 1, 1974

As we look back through the Proceedings of our Institute, we find few papers dealing directly with education and recruitment. Apart from papers prepared in the earlier decades of this century, there was little written discussion on the subject until the 1950s, and mostly this was by the professionals, the professors and lecturers who staff the various mining schools of Australia and New Zealand.I use the term "mining school" in its fullest and widest meaning, to cover all aspects from ore to metal, and not in the narrow meaning that the word might imply. At the same time, in restricting the parameters of this address to "ore to metal" I recognize that I am excluding the very important fields of physical metallurgy and materials science; this I do because there is a limit to the quantum of any paper, and in fact these subjects are more closely allied to the use rather than the production of metals.However, the lack of education papers does not mean that education has been regarded lightly by The Institute. Sir Maurice Mawby in his presidential address in 1968, reminded us of the original objectives of The Institute, one 'of which was, "To promote the arts and sciences connected with the economical production of the useful minerals and metals ...". Our present Royal Charter is more specific when it says that one of the objects of The Institute is, ". . . to encourage the study of engineering with special reference to mining and metallurgy ...". If we recognize that in itself membership of our Institute is one means of continuing our education, it is true that education has been a concern of The Institute since it was first founded.Occasionally in recent years, an intrepid president has ventured to tell the academics what the industry needs, and he generally does this in a "no-question" situation! However it is encouraging that those entrusted with mineral education have always accepted this; they keep coming back for more and ask us to tell them what we want, and they will provide it.In 1948 a considerable dialogue on education was initiated when a standing committee was established by the Council of The Institute. In the period 1949 to 1951, three papers were prepared under the chair...

Jan 1, 1974

By T. C. Woo

This report describes the program that studied the theoretical and practical aspects of the belt cleaning systems, investigated-the possibilities of a self-replacing and/or sell-adjusting belt cleaning device, and designed a horizonal pentagonal turret setup for the underground mine belt conveyors. This design resulted from comprehensive literature survey (both academic and commercial), actual mine visits, study of the mechanics of belt cleaning and bench-type experiments. It has complete working drawings and rough cost estimates.

Jan 1, 1977

One of the most significant problems experienced in land reclamation work has been the tendency of earthmovers to over-compact the subsoils and topsoils. The need for extensive subsoil drainage, because of over-compaction, becomes a very expensive exercise and can be attributed to poor planning. The problem has been addressed both at the Waihi and Huntly open-cast mines through the use of low ground pressure machines in the placement of subsoils and contouring. The use of subsoilers working to contour to aerate the soils is essential to integrate both the sub and topsoils so that significant root growth and drainage is established. Waihi's rainfall (approximately 200 mm annually) and light soils create difficulties in preparing for the final seed bed. A noticeable factor in preparation of the growing medium was the reaction of the lime particularly in the subsoils (damp), from a lumpy, quite heavy texture to almost a seed-bed texture within a period of approximately 72 hours. Also the high incidence of stone and debris which was not apparent in the placement of subsoils meant the job became very labour intensive. This will be overcome with the importation of a machine from the USA. All of the rubber tyred tractors used on these projects are four wheel drive in the 6S-aOhp range which for weight distribution and the safety factors allows for good landscaping techniques. Good engineering practices should ensure that slopes of no more than 3:1 be designed, keeping in mind that the long term planning must allow for maintenance and stock management of restored land.  In the preparation of the final growing medium the equipment used included: Caterpillar 05 LPG and blade; three-four wheel drive rubber tyre tractors; Super flow subsoiler; hydraulic twin spinner manure spreader; discs û two types; harrows; MF Seeder; Cambridge Roller and Duncan Rotatiller.

Jan 1, 1991

By D. Yuan, M. Sitter, S. St. Jean, M. Collins

The Ambatovy Joint Venture comprises an operating lateritic nickel mine, ore slurry pipeline, pressure acid leach plant and nickel refinery in Madagascar. The hydrometallurgical process selected by Sherritt for treatment of the Ambatovy ore is a long-term, sustainable approach to producing nickel. Sulphur, used to prepare hydrogen sulphide, which is used to produce mixed sulphide intermediate, is recovered in the refinery as ammonium sulphate fertilizer. Additional sulphur is used to generate sulphuric acid for treatment of the ore in the high pressure acid leach (HPAL) step; fossil fuel consumption is minimized by using the heat generated from the exothermic reaction between sulphur and oxygen in the acid plant to produce power and steam. Steam consumption is minimized by design of efficient flashing and preheat systems for HPAL, while the high temperature of the HPAL step serves to minimize acid consumption. Fossil fuel consumption by the operation as a whole is further minimized by locating the leach plant and refinery near the port of Toamasina and utilizing a 220 km slurry pipeline to transport ore from the mine to the leach plant. In addition, Ambatovy has demonstrated a strong commitment to sustainability programs such as the biodiversity management program at the mine and local procurement in Madagascar. In this paper, the hydrometallurgical process for nickel and cobalt recovery from Ambatovy ore is described, along with highlights of Ambatovy’s approach to sustainability in Madagascar.

Jan 1, 2015

By N. I. Jayaraman

High-pressure shrouded sprays were first tested on a bench to determine air-moving capability and dust collection efficiency. The bench-scale tests indicated that at 500 psi and above, the dust collection efficiency, when sampled downstream of a water eliminator, was about 99 pet for two types of nozzles. However, for the same water flow, the induced airflow was about three times greater in one type than in another. Since the only difference in the nozzles was the spray angle, this factor was important in air movement through a shrouded spray. Full-scale model mine tests were then conducted to determine the reduction in dust concentration behind the line curtain and at the operator position produced by high-pressure sprays in a shroud. The shroud was mounted on top of the boom of a model continuous miner, and high-pressure (greater than 500 psi) sprays were installed inside the shroud. The inlet of dusty air to the shroud was open toward the face and the outlet toward the exhaust line curtain. The high-pressure sprays were compared with conventional sprays mounted at the head of the continuous miner and directing water toward the face. The difference at the operator position (opposite side of brattice) was significant in that, under certain conditions, with conventional sprays an increase in respirable dust concentration of 471 pet was noticed compared with dry operation due to rollback from face. High-pressure shrouded sprays, on the other hand, decreased the dust concentrations at the operator position (opposite side of brattice) by 28.2 pct.

Jan 1, 1981

By Luis Giraldo

The installation procedure of fully grouted rebar bolts requires that the bolt be pushed through the resin grout until it is fully inserted in the borehole. Resin grout is a highly viscous fluid that is forced to flow through the annulus between the bolt and the borehole as the bolt advances. Variables such as bolt insertion speed, bolt vs. borehole diameter and grout viscosity determine the magnitude of the pressure generated ahead of the bolt tip. Under weak rock conditions, the magnitude of the pressure of bolt insertion is often sufficient to initiate hydraulic fracturing along joints or bedding planes that allow injection of grout into the strata leading to significant loss of bolt encapsulation. The grout pressure front has also been linked to gloving, a bolt installation problem that reduces bolt effectiveness. A series of tests were conducted to characterize the pressure of bolt insertion during bolt installation under various conditions. Analysis of the data shows three distinct stages of pressure build up during bolt installation. Understanding of the mechanisms involved may allow development of strategies for controlling the pressure buildup and its negative impact during roof bolting under weak rock conditions.

Jan 1, 2006

By N. Singh

Merensky Reef is mined extensively within the Bushveld Complex. In previously mined-out areas on the Merensky Reef horizon there are pillars, potholes and remnants that have not been mined. These unmined blocks of ground on the Merensky Reef horizon can influence the mining of the underlying UG2 Reef. The extent of the influence will depend on the size of unmined ground and the middling between the two reef horizons. This paper quantifies the influence of partially extracted Merensky Reef on mining of the UG2 Reef, and aims to provide recommendations for mining strategies, as well as regional and local support to achieve efficient and safe extraction of the UG2 Reef, for various middlings beneath the Merensky Reef horizon. In some cases it was found that relatively shallow UG2 Reef mining could encounter conditions similar to those experienced in deep and ultra-deep mining environments.

Jan 1, 2005

By Matthew Janes

Quality control procedures are increasingly important with today's higher capacity foundations and complex loading conditions. The need for a mobile, repeatable, nondestructive and economical load test method led to the development of an entirely new approach. The system described involves using solid propellant fuels to accelerate a reaction mass off the test pile. The force required to accelerate the reaction mass upward acts equally downward on the pile. Very high forces may be applied to the pile in a controlled, linearly increasing manner. The duration of the applied load is approximately 100 milliseconds. This rate of loading is slow enough to allow the pile and soil to react together as a composite rigid body. Pile/soil accelerations and velocities are low, typically 1 g and 1 m/s respectively. The effects combine to produce pile and soil response no longer dominated by the transfer of force via stress pulse (as with impact). Instead the pile force increases throughout the length of the pile, with pile top and toe stresses building in unison with time. This emulates the stress condition during static pile loading. Finally, state of the art instrumentation systems are used to obtain test data. Displacement is monitored directly using a laser datum and integrated receiver located at the centre axis of the pile. Force is also monitored directly using a calibrated load cell. Data is acquired and digitized using a 386 PC with user friendly software capable of producing load deflection curves and time histories in the field seconds after testing.

Jan 1, 1990

By Tom Treleaven

The widening of the Panama Canal to approximately 130 feet (40 m) for its entire length began just a few years ago. The original expansion program was slated for completion in 18 to 20 years, but has recently been reduced for completion within the next four years. This means that a tremendous amount of blasting at simultaneous points along the canal, by both the Panama Canal Commission (PCC) and many subcontractors, is necessary to achieve the new completion deadline. The accelerated program also imposed many logistical concerns, since marine trafIic is always heavy and cannot be stopped for blasting. Because some of the large and heavy cargo vessels clear the bottom of the canal by only about 6 feet ( 2 m), the blasting cannot result in any large boulders into the center of the canal, for fear of grounding and damaging a vessel, not to mention the traffic delays and lost income of approximately 1 to 2 million dollars per day.

Jan 1, 1997

By D. Nutakor

The ability of computers to create synthetic representations of the real world in virtual reality offers a number of opportunities to enhance training methods used in the mining industry. Unfortunately, the training effectiveness of virtual reality systems currently used in the mining industry has received only limited testing. Miner Simulation (MinerSIM), an augmented reality system with integrated hypermedia suitable for training underground miners in the basics of using a jackleg drill to install rock bolts in a virtual mine environment is in its evaluation process at the University of Missouri-Rolla Experimental Mine. This paper discusses evaluation methodologies of the MinerSIM system, which consists of experimental and control groups with control students learning via traditional lecture and text formats. Preliminary results from usability tests of the first part of MinerSim, which is an online tutorial on underground rock bolting, are presented.

Jan 1, 2008

By James Gibbs

In order to provide an initial approach to the deposits of oil shale, nahcolite, and dawsonite in the central area of the Piceance Creek Basin in northwestern Colorado, the U.S.B.M. and associated contractor personnel drilled and cased a 96-inch ID shaft to a depth of 2,371 feet. The shaft was constructed using "big hole" drilling techniques and succeeded in giving access to previously inaccessible deposits of the above minerals. This report documents the construction from its beginning in January 1977 to its completion in January 1978. Procedures used and problems encountered are discussed in derail.

Jan 1, 1978

By K. Short

Over the past several years, the mining and minerals market was overloaded with discussions around reviving mature terminologies like distributed control systems (DCS), programmable logic controllers (PLC), and the ?new comers?: hybrid control systems (HCS) and programmable automation controllers (PAC) and, in parallel, which technologies would be more appropriate for mining and mineral processing applications. Ten years ago, a careful comparative analysis would make more sense. Control approaches had very distinctive differences where users needed to choose the right approach.

Jan 1, 2012

By J. H. Nixon

A three phase program evaluated commercial proximity warning devices, developed and designed a microprocessor-based electrostatic field measurement instrument, and utilized this instrument to investigate the electro-static fields about power lines. The Phase I program consisted of test and evaluation of these commercially available proximity devices. The evaluation results were reported in the Phase I report entitled ?Evaluation of Proximity Warning Devices? dated 22 February 1980. The Phase II program resulted in the design and development of a microprocessor-based Distributed Sensor A.C. Electrometer which measures the electrostatic field present at 17 discrete locations along a crane boom. Operator control of the measurement system allows simultaneous electric field measurements from 17 probes, print out of the electric fields measured, and data archiving on magnetic tape for post measurement analysis. Under the Phase III program, electrostatic fields around a crane boom were measured by the instrument at 17 high voltage power lines of various voltages and geometries. The electric field data was processed and plotted versus boom distance from the power line. Analysis of the electric field data indicate that the distances at which a single sensor alarm will activate, vary by a factor of 3 to 1. This is due primarily to variations in boom orientation. The results also indicate that in the case of multiple power lines, a single electrostatic field sensor cannot reliably be used to determine the distance from a power line.

Jan 1, 1982

By Christopher F. Gleeson, Roger D. Thomas

"Abstract - Wawa has long been a center of mineral exploration activity and diamonds have been reported in the area since the 1930s. However, diamond exploration did not begin in the area in earnest until 1991. In 1993, Sandor Surmacz and Marcelle Hauseux of Saminex began a prospecting program in the area which culminated in their discovery of the "Sandor" diamond occurrence in an outcrop on the east side of the Trans-Canada Highway. They subsequently optioned the property to Spider Resources Inc. who obtained the necessary exploration permits from Algoma Central Corporation and undertook an exploration program. The diamonds at the "Sandor" diamond occurrence are hosted in the matrix of a spessartite dike composed of actinolite, biotite, and albite. Of the 64 similar dikes that have been sampled and analyzed to date, eight have been found to contain a total of 231 diamonds. Most of the diamonds are of high quality, although they are small.The dikes are non-magnetic and do not have any other geophysical characteristic that can be used to differentiate them from the adjacent country rock. All of the dikes discovered to date have been found by prospecting or by geological mapping by the Ontario Geological Survey. The dikes do not contain pyrope garnet or chrome diopside, two of the commonly used kimberlite indicator minerals. Instead, low Mg, high Cr, Zn-rich chromite, and ilmenites of variable composition, some of which lie within the field of kimberlitic Mg-ilmenite compositions, characterize the diamondiferous dikes. A regional-scale till sampling program for heavy minerals, and geochemical analysis of the <0.177 mm fraction, was used to further define the areas of occurrence of the spessartite dikes and to indicate additional areas for diamond prospecting. Heavy minerals in till that were most useful include: actinolite, chromite, and ilmenite. Geochemical analyses of the dikes show them to contain elevated concentrations of Ni and Cr and to be enriched in Ba, Co, V, Ca, Fe, and Mg relative to the surrounding rocks. Elevated concentrations of Ni and Cr in till occur overlying and down-ice of known lamprophyre dikes."

Jan 1, 2000

By Waldemar Lindgren

THE following pages present data accepted by many geochemists and geologists regarding the succession of minerals and the temperatures of formation in ore deposits affiliated with igneous rocks. They also present the individual views of the author on the composition of the solutions that were active and on the mode of deposition. He does not regard these views as speculations or hypotheses but as forming a well motivated and consistent theory. It is not certain, however, that all investigators will subscribe to them.

Jan 1, 1936

By R. L. Loofbourow

R. L. LOOFBOUROW 26.1-WATER FLOW, USE, EFFECTS, CONTROL Sec. 4 discusses ground water as a mineral resource. This section deals wits its control. 26.1.1-IMPORTANCE Flows of water have an important effect on the cost and progress of many deep excavations. The existence of water limits the methods which can be used in some and presents hazards in others. Lowering the water table may reduce the flow of springs and wells, with legal liability. Some mine water is used directly, some must he treated before discharge, and some contains dissolved solids which can be recovered profitably. Loss of life, property and production from flooding is grim, yet scores of mines have worked safely for generations under ground-water reservoirs, lakes and even the sea. The need for better control of mine water is measured by the severity of recent floodings, concern with the quality of the effluent, and direct and indirect costs of working wet ground. There are improvements in freezing in shaft sinking. pumps and their controls, treatment of mine water before it is pumped, bulkhead construction and certain efforts to reduce inflow. 26.1.2-PUMPING COST VS. COST OF WET WORK Direct operating and capital costs of pumping are more evident than indirect items, such as provision of extra standby power and maintenance facilities, The total of all these items is the cost of pumping water from an excavation. This is only a part of the extra cost of working wet as compared to dry ground. Less productive methods, less efficient equipment and more expensive explosives may have to he used in wet work. Wet rock plugs certain equipment. Maintenance is higher and labor less efficient. The cost of any means of keeping work drier should he weighed against the higher cost of working wet. The true difference in the cost of working wet ground, compared with dry, probably is known at only a few places (see checklist of cost items. Sec. 26.4.13). An extreme comparison of mining wet and dry ore is available from Ambrosia Lake, N.M. (Fig. 26-1). Between 1963 and 1967, a wet and a dry mine were worked by the same company under conditions otherwise comparable. Average operating cost at the wet mine, pumping 1,600 to 1,800 gpm. was $16.06 per ton of ore. The comparable figure for the dry mine was $7.50. Principal differences included the fact that the wet mine was worked from drainage levels below the, ore with rail haulage, the dry mine in the ore with off-track equipment loading and hauling to the shaft. In the wet mine, ore packed in chutes, cars and skips and froze in surface bins, stockpiles and trucks. Wet-mine costs included drilling drain holes, building and maintaining ditches and pumping water containing abrasive solids.

Jan 1, 1973