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By K. Thomson

The Mule Canyon gold deposit, located 14 miles ESE of Battle Mountain, Nevada, was discovered in 1986 as the result of a GFMC grass-roots exploration program. Drilling to date has identified six discrete orebodies which contain a demonstrated gold reserve of 8.487 million tons at an average grade of 0.136 oz/ton, totaling 1,152,000 ounces. Mineralization is associated with argillic alteration and silicification, localized along NNW trending high-angle faults within Miocene basaltic andesites. Trace element geochemistry at Mule Canyon is typical of upper level hot spring precious metal systems, displaying elevated Ag, As, Sb, Hg, and Se.

Jan 1, 1993

By J. W. Gulyas

Settling a contract for process design involves a negotiation between the design engineers and the client. Clients wish to offload as much risk as possible by seeking various guarantees about the process performance. Design engineers respond with preconditions and qualifiers, believing that the risk must remain with those who stand to benefit. This paper presents the engineers? point of view on guarantee types and precedents, performance testing, damages that may be claimed, and remedies that can be provided with particular reference to the mining industry.

Jan 1, 2010

Grouting is mainly used to improve mechanical properties or decrease the permeability of rock mass around civil and mining projects. The purpose of this paper is to present the most effective factors on grout penetration depth in rock mass. Such factors are essential for reliable estimation of the grout penetration depth and the expense for cement take of any grouting project. In this paper, about 50 different types of the relations presented so far by various researchers to estimate the depth of penetration in fractured rock were studied. The effective factors are classified to rock mass properties, grout properties, and operational factors. Results show that firstly, the discontinuities aperture and Lugeon value are respectively the most investigated factors of rock mass properties influencing on penetration depth. Secondly, the yielding stress, viscosity, and density of grout are the most effective factors of grout properties. Finally, grouting pressure has an intense effect among other operational factors. The investigations were also verified in Siah Bishe dam case study. Keyword: grout penetration depth, rock mass properties, grout properties, operational factors.

Feb 27, 2013

By D. J. Kunz

Myanmar Ivanhoe Copper Company Ltd. (MICCL) has been operating the Sabetaung- Kyisintaung (S&K) Project producing LME Grade A Copper Cathode using the Heap Leach-SX-EW Process since 1998. The mineralization is mainly Chalcocite and the mine has a life of 20 years at the designed annual production of 25,000 tonnes of cathode copper. Design capacity was achieved within two of months of start-up. The mine is among the world’s lowest cost, Heap Leach-SX-EW operations. Information regarding plant design and operation are presented along with the challenges lying ahead and the latest developments. Daniel Kunz is President and Chief Operating Officer of Ivanhoe Mines, and a director of MICCL. He has more than 20 years’ experience in mining, construction and engineering. Prior to joining Ivanhoe Mines in 1996, Mr. Kunz was Vice President and Controller of Morrison Knudsen Corporation, a major international mining and construction company. He was also President and Chief Executive Officer of MK Gold Company, a public mining company listed on NASDAQ.

Jan 1, 2001

By J. D. Goodrich

Success of The Carter Mining Company's safety program can be primarily attributed to "total immersion" of all operating and staff personnel in program design and implementation. Currently, the Company operates two surface coal mines in Campbell County, Wyoming. Total employment is about 440 and current annual production is about 15 million tons. The safety program has evolved from one which was administered primarily by staff personnel (the Safety Department) to one which requires active participation by line management and operating personnel. Lost time accident frequencies have declined from a high of 1.86 per 200K hours worked in 1978 to zero in 1982. Reportable accident frequencies have declined from slightly over 5 to slightly over 2 during the same period. Analysis of program results indicates that the most important achievement by the company has been to gain strong commitment to safe operation by all employees. It is important that program format and content be frequently changed and modified so that: 1) The requirement for safe job performance is communicated well and often, 2) The safe job performance message is trans- mitted in new and interesting ways, and 3) Operating personnel participate in design and implementation of the program.

Jan 1, 1983

By A. J. Plumpton

Centrifugal air classification and li-quid-phase sedimentation are the principal methods of industrially sizing materials of dimensions smaller than those handled by screens. Increasing application of materials such as composites and high performance ceramics has furthered the need for closely-sized, fine, industrial mineral and synthetic products of controlled properties. Sedimentation can be used to separate very small sized particles but introduces problems of liquid-solid separation, de-agglomeration and drying. Some of the advantages and limitations of centrifugal air classification will be discussed and laboratory and plant measurements using centrifugal machines will be presented to support the discussion.

Jan 1, 1990

By R. B. Tippin

The material balance computer program (MAT-BAL) developed at the Minerals Resource Research Center of the University of Minnesota, has been used in conjunction with routine process profile samples taken in the potash compaction plant at Great Salt Lake Minerals and Chemicals Corporation, Ogden, Utah. In this manner, a uniform data base is being established for the process, and selected key indicators are used for decisions in plant operation and maintenance. With present emphasis on improving product quality and increasing production rates, the standard data base system provides a means of measuring results from test programs to optimize the circuit. The development and application of this process control method is discussed. The compaction plant computer-assisted data base has been in existence for only two years, but it has made significant contributions to the knowledge of the process and continues to assist in monitoring the plant performance. It is anticipated that the material balance program will be adapted to the GSL flotation plant in 1979, and to other circuits in the potassium sulfate chemical plant.

Jan 1, 1979

By M. Michael, A. Felber

"Mining activities, especially underground mining operations, create great demands on utilized haulage means which cover a variety of different horizontal and vertical distances. In the course of the continuous optimization of the haulage process, the application of textile machine elements, in particular synthetic fiber ropes, offers new opportunities. Therefore the current level of knowledge needs to be improved based on extensive analyses. For the estimation of the scope of these analyses, different fields of application and occurring environmental influences which have an impact on synthetic fiber ropes during their use in underground mining have to be evaluated. The Chair Underground Mining Methods of the TU Bergakademie Freiberg works on a scientific project concerning the use of synthetic fiber ropes in underground mining operations. This paper focuses on the potential application of synthetic fiber ropes in haulage systems in underground mining and exposes critical influences as an outcome of the working environment. These first investigations are the basis for the development of an appropriate experimental series. SYNTHETIC FIBER ROPES FOR UNDERGROUND MINING OPERATIONS The main idea is to optimize underground haulage means to develop even more economic systems. The new and lightweight design of single machine elements seems to be the first step to accomplish this goal. An example is the lightweight design of shaft hoisting ropes. The commonly used steel wire ropes are very heavy and are endangered to snap due to their own weight when reaching a distinguishing length. Thus they may not or only conditionally be used for deep mining operations utilizing shaft haulage. Ropes made of high-tech synthetic fibers weigh only an eighth of steel wire ropes while displaying the same tensile strength. This relation is shown in Figure 1, based on the comparison of fiber strength and density. This could offer new opportunities for deep mining operations, which are anticipated by many mining companies. /1/"

Jan 1, 2015

By R. G. Benson

The San Luis deposit of Costilla county, Colorado contained 11,021,000 tonnes (12,149,000 tons) of ore at 1.4 g/t (0.040 oz/st) gold in two minable zones. Gold mineralization is associated with silicification and quartz-sericite-pyrite alteration localized in breccias along a low-angle detachment fault zone in Precambrian gneiss. Gangue minerals include chlorite, specular hematite, chalcopyrite, chalcocite, and fluorite. Mineralization is mid-Tertiary in age and has a direct genetic relation to the emplacement of felsic intrusions. Portions of the ore body are unconformably overlain by sedimentary rocks of the Tertiary Santa Fe Formation. The deposit formed during the early stages of extensional tectonism along the eastern edge of the present day Rio Grande rift.

Jan 1, 1994

By K. L. Wiley

In-situ leaching, initiated in 1986 at San manual, was economically developed in 1989. The primary reason for this lag time between startup and viable production was the time required for technical development. The technical development pursued comprised detailed design, development, and implementation of in-situ well construction methods, formulation of suitable well pattern arrays, and the development of extensive hydrogeologic and geochemical knowledge of the mineral deposit. Since 1989, the in-situ leaching program has become a viable and cost effective method to extract copper from the supergene mineralized zone of the San Manuel deposit. The in-situ leaching methods that are currently utilized have been progressively expanded and continually developed and will became the cornerstone of copper production from the San Manuel oxide mineral deposit. This paper presents an overview of the supergene hydrogeology, current design techniques, drilling methods and well completion, pump determination and setting, solution management, and future plans for the increased extraction of copper by in-situ leaching methods at the San Manuel mine.

Jan 1, 1993

By T. Yegulalp, R. Farrauto, A. Belova, M. Castaldi

Calcium oxide, with its ability to capture and store carbon dioxide, is emerging to become an important tool in carbon management. Calcium oxide can be used reversibly to capture carbon dioxide in situ and then be regenerated to produce a pure stream of carbon dioxide ready for sequestration; the Zero Emission Coal Alliance technology utilizes this property of calcium oxide to generate emissions-free electric power from coal. The reaction of calcium oxide with carbon dioxide resulting in thermodynamically stable carbonate is well understood; however, the efficiency of this reaction is limited by the diffusion of gases through bulk calcium oxide and through a layer of carbonate formed on the surface. In addition, the regeneration of calcium oxide is an endothermic reaction and is favored at high temperatures. The purpose of this paper is twofold: first, to address the diffusion limitation, a thin layer of calcium oxide, supported on a high surface area material, is studied thermogravimetrically to demonstrate the physical adsorption of carbon dioxide on calcium oxide. The adsorption is to take place at temperatures lower than required to form calcium carbonate.

Jan 1, 2007

By Robert S. Hendricks

LOCATION AND HISTORY The Lakeshore Copper property is located on the Papago Indian Reservation approximately 30 miles South of Casa Grande, Arizona. This major porphyry type deposit was discovered by El Paso Natural Gas Company in 1966. Following an extensive diamond drilling program, El Paso invited several mining companies, including Hecla, to examine the property with a view towards participation. Hecla's examination, and the attendant feasibility studies, led to agreements, which were finalized in September 1969, whereby Hecla would acquire a 50% interest in the property, and would act as operator. The Lakeshore deposit covers an area approximately 3,000 feet in width by 6,000 feet in length. It consists of an upper zone of disseminated copper oxides, averaging approximately 100' in thickness overlying a zone of disseminated copper sulfides up to 1,000 feet thick. Near the base of the disseminated ore is a blanket like zone of high grade copper sulfides, referred to as the tactite ore body. The mine is being developed to produce approximately 6,500 tons per day of oxide ore and 9,000 tons per day of sulfide ore. This represents a total daily production rate of 15,500 tons per day, which will be achieved by underground mining methods using rubbertired dieselpowered mining equipment. DEVELOPMENT LAYOUT The mine is being developed by two parallel 15° decline tunnels. The declines were collared 5,000 feet southeast of the ore body, and are being driven in a northwestery direction, to pass beneath the tactite ore zone. The declines will constitute the primary means of access to the underground workings. One decline (north

Jan 1, 1997

By P. J. Rua

The Piedras Verdes copper mine is a new run-of-mine (ROM), heap leach, solvent-extraction/electrowinning (SX-EW) operation located 21 km (13 miles) north-northwest of the town of Alamos in the state of Sonora, Mexico. The Piedras Verdes copper mine is wholly owned by Frontera Copper Corp. (FCC), a Canadian corporation, through its 100 percent beneficial interest in Cobre del Mayo S.A. de C.V. (CDM), a Mexican registered company. The January 2008, minable reserves were estimated to be 193.6 Mt (213 million st) at a grade of 0.36 percent copper. The overall recovery of total copper was estimated to be 61.9 percent. The property has an additional 17-year life and is designed to produce 31.7 kt/a (70 million lbs/year) of cathode copper. Construction commenced in early October 2005. The first copper cathode was produced 12 months later at a total capital cost of $100 million. Elevations at the site range from 150 to 300 m (490 to 985 ft) above sea level. The area has excellent infra-structure in the form of towns, power, water, roads, rail, airfield and access to the deepwater port of Guaymas (Fig. 1). The surrounding area is also famous for its numerous polymetallic (lead, zinc, copper, silver and gold) epithermal veins. Some of these were mined for more than 200 years and provided the wealth on which the town of Alamos was built. The original village of Piedras Verdes was located in the area of the proposed openpit mine and, consequently, it was necessary to construct a new townsite 6 km (3.7 miles) to the south before project development could commence. The new town site (Fig. 2), complete with power and water supplies, roads, sewer system, schools, clinic and recreational facilities, was completed and occupied by 49 families in September 2005. CDM received its remaining permits from the Mexican environmental authorities on Sept. 20, 2005. This enabled the company to proceed with full-scale development. CDM owns or controls 27 mining concessions covering the resource. Surface rights to the Piedras Verdes project were controlled by four Ejidos (communal agrarian and/or ranching societies) and five individual landowners. CDM has acquired all surface rights necessary for its mining operations and associated facilities either through outright purchase or long term lease agreements.

Jan 1, 2008

By L. Xu

Since the establishment of the standard dust concentration of 2 mg/m3, a strong effort has been made by mining engineers and researchers to provide better dust control equipment and procedures for underground coal mines. Particular areas of success have been control of dust generation by better coal-cutting strategy, better design of water sprays for dust suppression and air movement, use of scrubbers, and improved design of face ventilation systems. A drastic improvement occurred over time such that the average dust concentrations for continuous miner operators dropped from 6.5 mg/m3 in 1968 to 1.3 mg/m3 in 1980 and for auger, cutter, longwall, and roof bolter occupations from 2.7 mg/m3 in 1973 to 1.6 mg/m3 in 1980 (Niewiadomsky, 1983).

Jan 1, 1990

By W. A. Crosby

The ability of open pit mines to steepen overall final wall angles allows significant cost reductions as a result of reduced waste movement requirements. Final wall angles are principally controlled by three factors: geological conditions; hydrological conditions; and wall control blasting practices. The first of these factors is not controllable by the mine operator, the second can be influenced to some degree, but the last one certainly can be controlled, hence the current interest in final wall blasting practice at many mining companies. This paper discusses common blasting techniques employed to steepen final pit walls and outlines the attractiveness of moving from small hole high cost systems to the use of full size production drills as a means of reducing wall control blast costs. Attempts to make this change have been limited at many mines by the physical size of the drills and their inability to reverse drill. In the past, pres pi it, pre-shear or trim holes have had to be drilled vertically, at considerable distance from the upper bench toe, with the result that inter-berm face stability is reduced and final wall angles have to be made somewhat more shallow than desirable. The paper concludes with a description of how these problems can be overcome by utilizing the new Bucyrus 39R which has the capability of drilling at a ?15 degree angle underneath the machine. It is concluded that the resulting wall control blast designs will offer large mines improved final wall angles with resulting significant overall cost reductions.

Jan 1, 1998

By William M. Gray

[The products of mites hive historically beet a very large and important segment of total shipment transported by American Railroads. Much as the Mining transportation Executives right have wished for coal and other mineral deposits to be found along navigable rivers, where railroads have for years been competing with the very aggressive Army Corps of Engineers and the inland waterway operators, the mineable reserves are more often that not located in the arid west far from these "free" waterways. The rivers cannot go to the mines but the railroads could, did, and continue to invest it new lines to reach new mines. The mining industry and the railroad industry have good reason to rely upon each other. The former Northern Pacific Railway, the Great Northern Railway, the Chicago, Burlington and Quincy Railroad and the Spokane, Portland and Seattle Railway merged in 1970 to form the Burlington Northern Railroad, with Lou Menk as its first President. As unofficial spokesman for the industry, be had, for years, conducted a tireless effort to educate shippers, lawmakers and the general public of the single most critical problem confronting the railroad industry, the strangle bold of government regulator.]

Jan 1, 1985

By Clinton Birch

The multiple-criteria decision analysis is a technique that helps to find an optimal solution by evaluating conflicting criteria. In this study, an approach to perform multiple-criteria decision analysis for cut-off grade optimization, which considers the diverse stakeholder groups prevalent in the mining industry, is presented. The optimization model developed in this approach links the resource block model to the financial model, enabling the process to either maximize profit, net present value, revenue to the State, or extend the mine's life. To identify the optimal cut-off grade in each case, the Excel Solver function is utilized. Although it has limitations, the Solver function can still be modified to handle models with thousands of block values for determining input variables based on the target value. Following stakeholder engagement and dialogue, a single weighted average cut-off grade can then be determined. This approach is demonstrated for nine South African Witwatersrand gold mines.

Jun 25, 2023

By M. Amick, G. Swan, R. Hill, C. Pritchard

Falconbridge is a major basemetal producer in the Sudbury Basin of Ontario, Canada. The company identified a need to find a safe and cost-effective replacement for the welded wire mesh used to support loose ground during underground nickel mining. Falconbridge took a methodical approach to the concept of a spray-on liner as a screen replacement, proving the strength characteristics of the liner as a safe, cost effective and suitable method of supporting ground Compact, hydraulic mixing and spraying equipment were developed and are now in use at the Fraser Mine. Tekflex has been approved as a wire mesh replacement and has been in use since November 1998.

Jan 1, 2002

By Greg Partington, Darryl Thorburn, Charlene Wildman, Elisa Puccioni, Connie Payne, Campbell McKenzie

"Mineral prospectivity modelling of polymetallic nodule deposits has been completed over the Cook Islands Exclusive Economic Zone (CIEEZ) using the GIS based Weights of Evidence modelling technique. Polymetallic nodules, also known as manganese nodules, have been explored as a possible resource for a number of metals including cobalt since the early 1970s. Recent data on the nodule composition and abundance in the CIEEZ has led to a renewed interest in the prospectivity for manganese nodules in the region. The predictive modelling has used the most recently accepted mineral model for polymetallic deep-sea nodule deposition to identify factors that are most likely to map the presence of this type of mineralisation in the CIEEZ.Manganese nodules form on the deep seafloor as concretions formed by concentric layering of iron and manganese hydroxides around a core and they grow at a very slow rate, on the order of millimeters per million years. The available data for the CIEEZ indicates a greater abundance in the area of nodules formed by hydrogenetic processes, which are the result of slow precipitation of metallic components from seawater. The environment in which the nodules are most abundant is at depths between 4,000 m and 6,000 m in areas of low sedimentation rate. Hydrogenous nodules commonly grow on siliceous and pelagic clay sediment, they are less common on other types of sediment."

Sep 1, 2014

By W. L. Price

Since first introduced in the United States in 1964, rail mounted bucket wheel stacker-reclaimers have gained wide acceptance by users. The coal burning power plant group has adopted this new storage tool most quickly. The actual history is traced in this area in some detail. Installations in phosphate and steel mill ore storage and a listing of present users are included.

Jan 1, 1969