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By R. L. Roller

In recent years, there have been many articles and papers written on the use of specially designed belt conveyor systems in mining operations, either economic studies or actual experience. These papers generally conclude that the use of these systems can reduce overall costs from 10% to 40% over conventional methods using general purpose equipment (truck/shovel, scrapers, etc.). However, they also generally conclude that conveyor systems are inflexible and capital intensive. With the increasing cost of mobile equipment, the capital cost conclusion is losing steam, particularly when the costs of maintenance shops, road and ramp construction and other related start-up costs are thrown in. Attention here will be focused on answers to flexibility related questions, but first, a look at costs in general. Basic production economics tell us that when we have a small job to do, it is cost effective to use simple, low cost, general purpose tools which will have a minimum impact on total cost. It also tells us that when we have a large project, we can employ methods using special, relatively expensive production tools. Figure 1 illustrates what occurs on projects, of different sizes, with various quantities of production. With small quantities of work, the cost per unit of work starts out much lower using general purpose equipment, rather than using special purpose methods and equipment. However, at a relatively low quantity of work, the cost hits a lower limit and, regardless of how great the quantity of work, the unit cost can never go any lower.

Jan 1, 1985

By John G. Hall

Everyone forms his own mental picture when the subject of copper is mentioned. To an architect, copper is a warm, enduring metal with a quiet beauty; to the historian, man's first metal; to the product engineer, the best electrical and thermal conductor of all commercial metals; to the investor, a volatile stock; to the speculator, the daily price quotation; to those in the mining industry, the challenge of producing copper for rising needs in the face of rising costs and lower grades of ore. At this meeting, we will look upon copper as a key raw material in industry, in national defense, in technology, in world trade, and as a principal commodity in the economies of several developing countries. As miners, and most of us here are miners, we are prone to view our role as suppliers of copper. We locate, mine, smelt and refine the metal. In the complexities of today's world, however, following a period of the longest domestic copper strike in history which caused critical world-wide shortages and widely fluctuating prices; it becomes necessary for all of us to concern ourselves with the whole spectrum of copper affairs -"from mine to consumer " But first we need to look at the miner's side of the picture -- capacity and production. We will examine these functions in terms of the whole world -- not simply the free world. Nature did not endow all regions of the earth equally, and copper in world trade has a way of ignoring political boundaries. Science and technology, as well, know no national boundaries. It is said that the "Engineering & Mining Journal" has as many readers in the Communist World as in the Free World. Nor is this a one-way street. We presently have available to us in the. U.S., cover-to-cover translations of many Communist World mining and metallurgical journals.

Jan 1, 1968

By Richard L. Wedertz

Although the physical appearance of excavating equipment doesn't seem to have radically changed over the past decade, important changes within the products and an innovative attitude on the part of the engineer in his design approach is becoming increasingly evident. The new philosophy is to go beyond simple refinements of existing designs that simply produce a machine which further reduces overall cost per ton or per cubic yard of material moved and to do it more efficiently than ever before. Standard ideas and preconceived notions have been discarded and have given way to providing a design and a machine that is best suited to get the job done. Understanding that the application will not always fit the machine, but, in most cases, the machine should fit or suit the application is a foremost consideration in the engineers' design criteria.

Jan 1, 1973

By M. A. Vergara, J. A. Botín

"The decline of the “super cycle” has placed an end to a decade of production-focused strategies, with operating cost growing at rates higher than production. Today, the sector is placed on a tough ride and forced to shift focus to cash preservation and efficient cost management. However, most cost management systems in the minerals industry are not conceived as value driving tools but to meet financial accounting and reporting needs. This research draws from a the development of an innovative cost management methodology that applies Activity-Based Bottom-Up cost budgeting and continuous improvement tools to develop a value-driven cost management system for sustainable improvement of operational efficiency and cost reduction. The methodology was successfully tested in the Andina underground mine III Panel sector of Corporation del Cobre (CODELCO), in Chile. INTRODUCTION Cost management is fundamental to profitability of any industrial project. Even more essential in mining, an industry that deals with commodities, which prices are dictated by the market and are beyond the management capacity of the company. The end of the mining “super cycle” and the advent in 2008 of the Global Financial Crisis (GFC), placed an end to a decade of production focused strategies, with operating cost growing at rates higher than production. The sector was placed on a tough ride and forced to shift focus to cash preservation and efficient cost management. Many mining companies have seen themselves into the urgent need of cost management systems capable of achieving sustainable productivity gains and consistent profitability. Cost management is composed of three main processes: estimation, budgeting and control [1]. A number of conventional techniques have been used for cost estimation and budgeting for many years. However, most cost control systems in the minerals industry cannot be referred to as “cost management” since they are conceived to fulfil accounting and reporting needs, rather than to improve operational efficiency [2]. In general, conventional cost budgeting and control systems in mining use a “top-down” methodology, which lacks of necessary details, and fail as a management tool leading to undesirable results [3]."

Jan 1, 2016

By A. S. Speirs

Over the last few years, the never-ending search for mineral wealth has taken the exploration efforts of Canadian mining companies further and further into the High Arctic and isolated locations where regularly scheduled transportation and communication facilities are nonexistent. Names such as Black Angel, Nanisivik, Asbestos Hill, New Quebec Raglan, Rabbit Lake, and Arvik are today frequently mentioned in mining publications. Twenty years ago, mining in these locations was unheard of, mainly due to logistic problems. However, improvements in the design and use of helicopters, STOL aircraft, and icebreakers in northern areas have helped to overcome these problems, making these locations more attractive to mining companies. Since 1969, when Redpath completed its first Arctic project at Texas Gulf's Scrathcona Sound property on the northern tip of Baffin Island, Redpath has been actively involved in contracting and engineering projects in three general areas: the High Arctic, Ungava and Greenland. A map showing some of these projects is shown in Figure 1. In these areas, permafrost conditions exist from a depth of 274 metres in Ungava to a depth of approximately 610 metres in the Little Cornwallis Island area, with rock temperatures ranging from -5°C to -13°C. Outside temperatures range from a low of -50°C in the winter to a high of 21°C in the summer. High winds in the winter result in wind chill factors lower than -73°C

Jan 1, 1980

By L. Frost

The establishment of a retreat system of longwall mining in this submarine coal field has been under study for many years and, although in special cases there have been limited local applications of this method of mining, there has been no attempt until quite recently to establish a uniform system of longwall retreating' in this area (see Figure 1) Where retreat walls were established, it was strictly as a result of physical, rather than economic conditions. In some of the operations- of the Corporation, where the coal was liable to spontaneous combustion- or the area subject to bumps as in No. 2 Mine of the Cumberland Railway and Coal Company in Springhills the recovery of the coal on a retreat system was more or less a necessity.

Jan 1, 1964

By C. L. Lin

A PC image-based, on-line instrument for the measurement of coarse particle size on a conveyor belt is under development. Both the hardware and software required to implement such a system are discussed, including the interface for the special image acquisition hardware. The system concept is given with examples to illustrate the step-by-step procedure for the implementation of image-processing algorithms.

Jan 1, 1992

By Richard M. Tinlin

Some of the practices of the mining industry that may place an undesirable stress on the groundwater environment are coming under increasing scrutiny from legislators and regulatory agencies. Among these practices are mine dewatering, the use of tailings ponds, land rehabilitation, and technological innovations such as in situ leaching of waste clumps and ore deposits. Pernichele, noting that 24 states have enacted legislation controlling to varying degrees the environmental effects of mining, has emphasized the importance of assessing the potential for damage to groundwater when evaluating, planning, and designing mining projects. 1 Illinois has enacted legislation requiring anyone opening, operating or abandoning a mine site to obtain a permit from the Illinois EPA. The law is one of the first to require regular monitoring and reporting to a control agency. Legislation has also been recently enacted at the national level that will have a significant impact on the mining industry; e. g., the Federal Water Pollution Control Act Amendments of 1972 (Public Law 92-500). The stated objective of this Act is to restore and maintain the chemical, physical and biological integrity of the nation's waters. Specifically, according to Sec. 102(a), the Administrator of the U.S. Environmental Protection Agency (EPA) is required to prepare or develop comprehensive programs for preventing, reducing or eliminating the pollution of the navigable waters and groundwaters and improving the sanitary condition of surface and underground waters. The definition of the terms "pollution" and "pollutant" is of particular significance to those who must comply with PL 92-500. The definitions are quite broad and include most of the adverse water quality effects of man's activities. As defined in Sec. 502(19), "pollution means the man-made or man-induced alteration of the chemical, physical, biological and radiological integrity of water." Within the Act, the list of pollutants includes dredged spoil, solid waste, incineration residue, chemical wastes, radioaetive materials, heat, wrecked or discarded equipment, rock, sand, cellar dirt, and industrial waste discharged into water.

Jan 1, 1973

By Rory P. A. Ball, Mark Briggs, Martin Dix

"Tunnel professionals should inform project stakeholders on the reality that tunnel projects are not 100 percent devoid of the need for excavations or public inconveniences during both design and construction phases. Competing stakeholder objectives to limit these disruptions must be weighed against the need to mitigate risks and to produce a constructible, operable and maintainable end product. Perhaps the approach we should take with stakeholders, also known as Authorities Having Jurisdiction (AHJs), is sharing memorable case studies that bring to life the potential risks so often buried within lengthy risk registers. This paper provides a sobering case study describing what can occur if the presence and/or location of utilities and other obstructions are not fully understood due to restrictions placed on exploration or mining operations. In this instance, the Microtunnel Tunnel Boring Machine (MTBM) encountered a buried concrete structure, followed by rows of abandoned wood piles, before finally colliding with an active high-pressure gas main under a bustling coastal highway. Multiple stakeholders imposed tight logistical and other work restrictions, compounding the difficulties experienced during the drive. However, the difficulties were effectively managed through the project team’s proactive collaboration and communication with everyone involved. INTRODUCTION Some of the most important decisions that influence the ultimate success or failure of a project may not be made by design engineers. Instead, these decisions are often made by project stakeholders and third-party agencies. Tasked with protecting the best interests of their users, these agencies are cautious of potential impacts associated with project construction and subsequent use. Unfortunately, actions required (or restricted) by stakeholders often result in unwanted ripple effects that negatively affect the very users they are trying to protect. For example, a mandate limiting a shaft site to an unreasonable size may be intended to reduce local business impacts, but may actually increase impacts as more supply and truck hauling is required."

Jan 1, 2016

By Richard W. Amerman

The final cost and quality of a project employing equipment, labor, and materials is dependent upon the expediency and extent to which each of these parameters are used. An ideal solution then, would be one in which three solvable equations were given for each particular situation. The equipment, labor, and materials could then be solved for, and the perfect job would result. In reality, however, the ideal and most economical solution is seldom attainable by solving three given equations. Therefore, knowledge, experience, and sometimes guesswork must be relied upon when correlating equipment, labor, and materials. Drilling and blasting, in particular, is one operation which normally involves more uncertainty than other operations. It is also an operation in which the outcome is extremely critical for two reasons. First, the cost of the operation that follows drilling and blasting is dependent upon how well the material is fragmented. Second, once the drilling and blasting has taken place, it is impossible to return to the area, without considerable expense, and correct any mistakes that might have been made. Therefore, what is desired is a method by which drilling and blasting operations can be performed yielding optimum results at the lowest cost; this can best be accomplished by having the relationships between equipment, labor, and materials prior to their use. For obtaining best results, the selection of these three relationships must be based on knowledge, experience, and as little guesswork and uncertainty as possible.

Jan 1, 1969

By B. A. Filas

Stabilizing fine coal refuse ponds for reclamation at Monterey Coal Company's No. 1 Mine has been difficult. Entrained water in the stored refuse causes liquefaction as reclamation caps are placed, resulting in additional material requirements than originally projected to stabilize the pond surface. Laboratory results indicate that in-place refuse densities may be substantially improved at No. I Mine by converting from a single-point to a managed slurry distribution system. Increased densities result in improved storage efficiency, less entrained moisture and a more stable refuse mass, thereby providing an improved working surface for reclamation and improved post-closure cover stability.

Jan 1, 1993

By Sun K. Kim

Hydrometallurgical processes are not free of environmental regulations. A clear understanding of the regulations under which the minerals industry operates delineates processing requirements at early stages. This paper deals' with federal environmental regulations with emphasis on the hazardous waste regulations promulgated in May, 1980. The procedure of EP toxicity test and an example of the test are described. Brief account is given of the current trend and future outlook of regulations.

Jan 1, 1982

By G. L. Simmons

Aqueous pressure oxidation at low temperature, although desirable from a process engineering and operations point of view, presents unique problems when temperatures approach 160°C (320°F). In developing the pressure oxidation process for the Lone Tree Mine, elemental sulfur formation and agglomeration with pyrite proved to be a problem. This paper discusses some of the unique features of the Lone Tree sulfide deposit and its amenability to low temperature oxidation. Problems encountered during pilot plant operation and their solutions are discussed.

Jan 1, 1993

By Q. Xu

Adsorption of nonionic/anionic surfactant mixtures on kaolinite has been studied with sodium dodecylsulfate as the anionic surfactant and octaethyleneglycol mono-n-dodecylether as the nonionic surfactant. Synergistic interaction between these surfactant was found to cause adsorption of the nonionic surfactant with its hydrophilic chains protruding into the bulk, leading to substantial changes in wettability and dispersion characteristics of kaolinite. Similarly, hydrophobicity changes are observed also for silica particles upon adsorption of nonionic ethoxylated alcohols owing to possible changes in the orientation of the adsorbed surfactant molecules at the interface.

Jan 1, 1991

By Kenneth N. Weaver

Introduction and Historical Background State Geological Surveys have been deeply involved in industrial minerals from their inception beginning in the first half of the 19th Century. To Massachusetts belongs the credit of having carried out the first Geological survey under state auspices on the Western Hemisphere. One of the causes leading up to this survey was. Governor Lincoln's message to the legislature of May 29, 1830, from which I quote in part: "Much knowledge of the natural history of the country would thus be gained (from a geological survey), and especially the presence of valuable ores, with the localities and extent of quarries and of coal and lime formations, objects of inquiry so essential to internal improvements and the advancement of domestic prosperity, would be discovered.". Similar phraseology is present in practically all of the initial organic acts creating the first State Surveys. High on the list of priorities for these embryo surveys was an inventory of the mineral resources of the State with particular emphasis on the industrial minerals. Prom these early beginnings, the state surveys have developed a great wealth of geological data either directly or indirectly relating to the development of mineral resources. One can gain some conception of the effort that state surveys today place on industrial minerals studies by noting the projects in which they are engaged as reported in the State Geologists Journal. In 1970, for example, approximately

Jan 1, 1972

By H. J. Brown

Pluess-Staufer (California) Inc. Lucerne Valley California operation is one of the largest producers of high brightness high purity fme grind limestone products in western North America. The San Bernardino Mountains area of southern California contains the largest high brightness, high purity limestone mining operations and undeveloped reserves in western North America (Fig. 1, Brown 1987). Combined annual production of high brightness limestone products from several operations is approximately 1.5 million tons, with an estimated gross value of $75 million dollars per year (Fig. 2). An additional 5.0 million tons of cement grade limestone is mined by several large cement producers in the nearby Mojave area (Brown, in press). The purpose of this paper is to summarize the geologic setting, genesis and mining of white, high purity crystalline limestone by Pluess-Staufer (California) Inc.

Jan 1, 1994

By Wallace W. Key

Problems of marketing industrial minerals to chemical manufacturers are manifold. In addition to the difficulty of establishing demarcation lines between "crude" and "processed" industrial (nonmetallic) minerals, and "industrial mineral compounds" further uncertainty exists because some chemical manufacturers do not talk the same language as the industrial mineral producer. For example, paint technologists use "rutile" and "anatase" to describe highly refined chemical compounds. The earth scientists use these terms to describe naturally occurring minerals. Further, marketing research problems are intensified because of the overlapping data of the Standard Industrial Classifications (SIC) groups, and the inexactness of "Chemical Industry," "Chemical and Allied Products Industries," and "Chemical Process Industries," which are widely variable in meaning but are often used interchangeably. Bureau of Mines information Circular 8244, "Minerals for Chemical Manufacturing," was the out¬growth of an attempt to unravel some of the problems caused by overlap of statistical data compared with actual industry practices. Using this study as a base, specific industrial mineral applications of some important sub-industry groups were analyzed for the; California chemical industry. Differences between local and national practices were compared. Practices usually differed, depending on cost and availability of alternate minerals, climate, idiosyncrasies, local regulations, and other conditions. Bureau of Mines Information Circular 8260, "Mineral Fillers for the California Pesticides Industry," is the first such analysis of, a sub-industry group. Other such studies are underway. Obtaining national data is easy, but to be able to compile meaningful information which can be revealed on a regional and State basis generally is difficult and often impossible. This paper will briefly emphasize some of the industrial mineral problems encountered, and bring out the needs and benefits being derived through the continued cooperation of authoritative officials concerned with supply and consumption of industrial minerals in government and industry.

Jan 1, 1965

By William Gleason

"On April 4, 2017, the largest earth-pressure-balance tunnel boring machine (TBM) ever built finally completed its 2.7-km (1.7-mile) journey beneath Seattle, WA, nearly four years after it began boring the SR-99 tunnel that will eventually replace Seattle’s Alaskan Way Viaduct.By now, readers of this publication are familiar with the ordeal that began on Dec. 6, 2016, when the machine overheated and shut down. Until that point, the TBM, named Bertha, had grabbed headlines for being the largest in the world with a 17-m (57.6-ft) diameter face. But after the incident that stopped the progress, the headlines suddenly stopped focusing on the engineering marvel of the tunnel project and began asking what went wrong. Just 300 m (1,000 ft) into the tunneling journey the machine was stuck, unable to move forward and impossible to retract.The project’s contractors, Seattle Tunnel Partners,(STP JV) – a design-build consortium comprised of Dragados - USA, Tutor Perini, say a 20-cm (8-in.) steel well-casing buried in the path of the machine caused the problems that halted the TBM. The Washington State Department of Transportation (WSDOT) disagrees, and the issue over who ultimately pays for the repairs is now with the courts.Eventually, engineers determined the best way to get Bertha back to work was to dig a 36-m (120-ft), deep concrete lined shaft pit in front of the machine and lift the 1.8-kt (2,000-st) cutterhead out for repairs. The repairs took two years but eventually the machine resumed mining in January 2016. In April 2017, the TBM finished building the tunnel, breaking through at the tunnel’s north end near Seattle’s Space Needle, with little to no ground surface movement measured on the entire alignment.While the cause of the TBM breakdown and who should pay for repairs was debated above ground, the work below ground continued. David Sowers, deputy program administrator, engineering and program management with WSDOT, told Mining Engineering during the 2017 Cutting Edge Conference in Seattle that in addition to the technical marvel that the tunnel became, the fact the parties involved were able to work through the unprecedented challenge is a great example of how to overcome challenges on massive projects."

Jan 12, 2017

By Thomas J. Neil, O&apos

Mine land reclamation is a comparatively new science-Although some mining companies point with pride to reclamation efforts of 20 to 30 years ago these were the exception rather than the rule. In the last ten years the skyrocket of environmental awareness has been awesome to behold. Future shock gripped mine operators everywhere as they struggled to cope with rapidly changing and escalating demands. The initial result was that two divergent points of view became dominant. Environmentalists said, "Put it back the way it was," and the miners responded, "Let's grow some weeds and hide it." These views are not surprising as they represent rather obvious alternative responses, albeit at opposite ends of the decision spectrum. The former case has prevailed more often than the latter, as most state and federal legislation -- both proposed and passed -- has required drastic alteration of the post-mining landscape so that evidence of prior mining is largely obliterated. An exception to this has been in porphyry copper country where the infrequent abandonment of mines has given emphasis to the second philosophy -establishing vegetative cover on mine waste materials. Now, it should come as no revelation to most mining people that both of these approaches to mine reclamation suffer from serious drawbacks when applied to open pit copper mines. First, whereas waste dumps and tailings dams can be vegetated with some aesthetic benefit, the massive presence of copper mining operations remains very prominent. It is difficult to conceal an open pit copper mine. Second, returning open pit copper mines lands to their original topography and productivity is simply not a reasonable alternative.

Jan 1, 1976

By V. D. Hanson

When maintenance of a plant or operation is under discussion immediately three "M's", all in short supply, are brought to mind - money, men and markets. This paper will present what currently is being done at our plants and its effect on the 3 "M's". Examination of coal realization figures (F.O.B. Mine) from 1945 to the present reveals the fact that open and free competition can and will meet market conditions. The industry, without benefit of advantages afforded tax and transportation wise to oil and gas, remains the backbone of the energy market of United States. Figure No. 1 shows the realization figures from 1945 through 1962 compared to the hourly earnings. Note that through 1945 to 1948 F.O.B. prices increased $1.93 per ton while hourly earnings increased $.66 per hour. Since 1948 (with the ex¬ception of 1957) F.O.B. prices have declined $.45/ton, while hourly earnings have increased $1.23 per hour. Basically the maintenance men possibly represent the highest increment rate in the overall hourly earning.

Jan 1, 1963