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By Seshold P

The cost of capital is the rate at which a project's cash flow should be discounted to obtain the Net Present Value. The cost of capital is a weighted average of both debt and equity funds of a company, on an after tax basis. Two methods are described for calculating a company's cost of equity, the Dividend Valu- ation Model and, more importantly, the Capital Asset Pricing Model. A worked example is presented where the cost of capital was obtain- ed for two resource companies. The application of the cost of capital was illustrated by way of a mining equipment replacement problem. The paper outlines refinements and problems that may be encountered with the use of the cost of capital, and concludes that it is an integral part of any project evaluation.

Jan 1, 1983

By D. W. Alexander

Mine fires, explosions, spontaneous heating and inundations are among the leading causes of catastrophes (unplanned, temporary sealing and recovery of major mines). Many reports are available that detail company efforts to re-establish mining operations and agency efforts to regulate away the causes, but the associated costs are rarely included. The increasing scale of coal operations concentrates earning potential and the financial risk of business interruption in fewer locations. Underground coal mine catastrophes are low probability, high loss events that happen nearly every year. This paper will present an evaluation of coal mine catastrophes from case studies.

Jan 1, 2003

By L. B. Rothfeld, R. L. Dolzani

This paper presents preliminary results of a US Bureau of Mines (USBM) study of potential costs of compliance with possible federal regulations for copper heap and dump leaching. The regulations could arise under amendments to the Resource Conservation and Recovery Act (RCRA) and/or the General Mining Law. Estimates are given for the cost of compliance with possible technology standards that would require the use of liners and closure caps regardless of terrain and underlying geology and hydrology. This cost is compared to the cost of compliance with 1992 state requirements for terrains typical of those found at existing copper leach sites in the southwestern United States. Incremental compliance costs are found to widely exceed screening criteria used by the US Environmental Protection Agency (EPA) to denote significant economic impact.

Jan 1, 1995

By L. B. Rothfeld

This paper presents preliminary results of a Bureau of Mines study of potential costs of compliance with the federal Resource Conservation and Recovery Act for copper heap and dump leaching. Specifically, estimates are given for the cost of compliance with possible technology standards that would require the use of liners and closure caps regardless of terrain and underlying geology and hydrology. This cost is compared to the co lit of compliance with present state requirements for terrain a typical of those found at existing copper leach sites in the Southwestern U.S.A. Incremental compliance costs are found to widely exceed screening criteria used by the Environmental Protection Agency to denote significant economic impact.

Jan 1, 1993

By L. B. Rothfeld

In anticipation of RCRA reauthorization and subsequent rulemakings, the Bureau of Mines is studying potential economic impacts of RCRA on mining. For U.S. copper heap and dump leaching operations in a variety of terrains, the cost of liners and closure caps to comply with RCRA Subtitle D ranges from $55 million to $158 million per site, or about $500,000 per hectare ($200,000 per acre). If RCRA technology requirements and financial assurance had been required on current operations, 27 to 100% of production from heap and dump leaching would have been non-competitive at market prices between $2,310 and $1,650 per metric ton ($1.047 and $0.75 per pound) copper. This result is based on an analysis that considers return on capital, corporate overhead, marketing, and freight costs as well as operating and maintenance costs at the mine. Over the same price range, economic analysis using the IMPLAN input-output model on one-or two-county regions indicates potential net job losses of about 570 to 2,700 jobs. Total economic output of those counties could be reduced by about $180 million to $360 million.

Jan 1, 1994

By H. R. Reed

THE cost of hoisting with electricity in deep mines is a matter about which little information has been published. This paper makes a detailed study of such costs and presents the information in a series of curves. In particular the curves show the cost of hoisting ore from depths varying from 500 to 7000 ft. vertical with the shaft at 70º incline for the double cylindroconical and double cylindrical drums, the hoists operating balanced, using Ward Leonard and Ilgner-Ward Leonard control, and designed for most economical operation from each depth. Operation with the double cylindrical drum is expanded to cover hoisting from 2000 to 5000 ft. using equipment designed for 5000 ft. and from 4000 to 7000 ft. using equipment designed for 7000 ft. Additional curves are included to show the ratings of the necessary hoist motors, energy input per hoisting cycle and size of flywheel in tons for complete equalization when the Ilgner-Ward Leonard system is used, also hoisting efficiency. The duty imposed on a mine-hoist motor fluctuates between wide limits during a cycle of operation. The demand on the motor may vary from a large horsepower value near the beginning of the cycle to a small or a negative demand near the end of the cycle. Such factors as tonnage to be raised per hour, depth of shaft, and balanced or unbalanced operation have such a marked effect on the operating cycle and vary to such an extent for different mines that no set of rules can be formulated for quickly determining the size of the motor required. The duty cycle from which the motor rating is derived must be determined for each case according to the conditions of the proposed hoisting operations. The motor torque required at the cardinal points of the duty cycle is determined from the moment or torque in pound-feet necessary to raise and lower the load and ropes, accelerate and retard the load, ropes, drum, etc. The torque diagram depends largely upon the type of drum. Two different types of drums, if used on exactly the same duty cycles, may have widely different peak demands and capacities of hoist motors. The essential feature in the design of hoisting drums and in determining

Jan 1, 1937

By H. R. Reed

THE cost of hoisting with electricity in deep mines is a matter about which little information has been published. This paper makes a detailed study of such costs and presents the information in a series of curves. In particular the curves show the cost of hoisting ore from depths varying from 500 to 7000 ft. Vertical with the shaft at 70° incline for the double cylindroconical and double cylindrical drums, the hoists operating balanced, using Ward Leonard and Ilgner-Ward Leonard control, and designed for most economical operation from each depth. Operation with the double cylindrical drum is expanded to cover hoisting from 2000 to 5000 ft. using equipment designed for 5000 ft. and from 4000 to 7000 ft. using equipment designed for, 7000 ft. Additional curves are included to show the ratings of the necessary hoist motors, energy input per hoisting cycle and size of flywheel in tons for complete equalization when the Ilgner-Ward Leonard system is used, also hoisting efficiency. The duty imposed on a mine-hoist motor fluctuates between wide limits during a cycle of operation. The demand on the motor may vary from a large horsepower value' near the beginning of the cycle to a small or a negative demand near the end of the cycle. Such factors as tonnage to be raised per hour, depth of shaft, and balanced or unbalanced opera-tion have such a marked effect on the operating cycle and vary to such an extent for different mines that no set of rules can he formulated for quickly determining the size of the motor required. The duty cycle from which the motor rating is (derived must he determined for each case according to the conditions of the proposed hoisting operations. The motor torque required at the cardinal points of the duty cycle is determined from the moment or torque in pound-feet necessary to raise and lower the load and ropes, accelerate and retard the load, ropes, drum, etc. The torque diagram depends largely upon the type of drum. Two different types of drums, if used on exactly the same duty cycles, may have widely different peak demands and capacities of hoist motors. The essential feature in the design of hoisting drums and in determining

Jan 1, 1937

The mining industry is generally regarded as a high risk industry, mainly because of the difficulties in estimating the tonnage and grade of mineral resources, the fluctuations in metal prices, mining problems and other problems which occur with mining in offshore and remote locations, such as appropriation or disruption to supply. As a consequence, finance providers require a high reward from mining projects. In the past two decades, the development of "mega" projects has led to the packaging of the finance becoming more sophisticated. Some would see this move as a measure of the evolution of banking rather than an intrinsic facet of mining finance itself. Project financial managers now require a thorough knowledge of all the financial tools which are available and have to be aware of the funding options so that they can put together a finance package which minimises the cost of the financing with the risk spread adequately between the partners of the financing. The different sources and types of finance for mining projects are described herein along with the factors which determine their costs. To understand the ramifications of financing mining projects, it is essential to appreciate the fundamental difference between debt and equity, which illustrates the importance of gearing. Costs of finance are determined by the interaction of supply and demand forces. Bankers and other financiers have become more adept at isolating a wide selection of risk elements and have devised a formidable range of insurance mechanisms. There is still a lot of money looking for good project risks and if a good project is properly presented and structured, financing can be obtained in today's market.

Jan 1, 1990

By Jr. Lownie

Estimates of the cost of producing any commodity generally fall into several classes depending upon the motives and needs of the estimator. There are estimates intended to show how low costs might be with favorable conditions if everything goes well. At the other extreme, there are estimates which show how high costs might be if troubles develop. The estimates in this paper for the cost of producing direct reduced iron (DRI) are accompanied by discussion to point out how the final figures may be adjusted in either a promotional or a conservative direction. Because we do not have a specific process and a particular set of conditions in mind when discussing this subject today, this paper deals with the general situation, with considerable attention to how the estimates can be made more specific once one knows the particulars of a given situation.

Jan 1, 1978

By P. E. Sperry, J. M. Duncan

INTRODUCTION The purpose of the report on which this paper is based is (1) to evaluate the potential for cost reduction of urban mass transit tunnels by use of alternative materials transport systems during the tunneling process, and (2) to identify research and development program elements to assure that the materials transport system will not become the limiting factor for the rate of excavation. The approach taken was: Review the state of the art of urban tunneling by extensive interviews with representatives of tunnel contractors, equipment manufacturers, government agencies and consultants, and by review of recent literature.

Jan 1, 1979

By Lebeau M., P. Duguay

"The cost of occupational injuries and diseases in the mining industry in Quebec was estimated for the period of 2010 to 2012. The method used takes into account the financial and human costs assumed by employers, workers, and the community. To better direct research and prevention toward issues with the most significant consequences, the results are presented in various ranking tables, which stakeholders might find useful.RÉSUMÉ Le coût des accidents du travail et des maladies professionnelles dans l’industrie minière au Québec a été estimé pour la période 2010-2012. La méthode utilisée prend en compte les coûts financiers et humains endossés par les employeurs, les travailleurs et la communauté. Afin de mieux orienter les recherches et la prévention vers les problèmes ayant les plus graves conséquences, les résultats sont présentés dans divers tableaux de classement, qui seront d’une grande utilité aux parties prenantes. INTRODUCTIONThe mining industry is much safer today than it was 30 or 40 years ago, mainly due to a more qualified workforce, the use of automated equipment, and a corporate culture more focused on occupational health and safety (OHS); however, the number and the severity of occupational injuries and diseases continue to make this industry one of the most hazardous. In the province of Quebec, the mining industry accounts for approximately 0.4% of paid workers but is the source of 4% of fatal work accidents. It is, therefore, important to continue the prevention efforts already underway in the mining industry.The difficult global economy, which has affected the mining industry in the last few years, is an opportunity to reaffirm that sound management of OHS can have a positive impact on companies’ productivity and profitability. Occupational injuries and diseases are costly for the companies concerned and for society as a whole. Reducing their occurrence makes it possible to reduce not only the size of workers’ compensation board contributions but also several other financial and human costs."

Jan 1, 2018

By Robert B. Scott

Acid mine drainage, discharging from coal beds, has polluted our streams and rivers since early time. These pollutants affect water quality by lowering the pH, reducing natural alkalinity, increasing total hardness, and adding undesirable amounts of iron, manganese, aluminum and sulfates, The tangible damages are the costs involved in replacing equipment corroded by the acid water, additional treatment costs at municipal and industrial water treatment plants, and damages resulting from corrosion of steel culverts, bridge piers, locks, boat hulls, steel barges, pumps, and condensers. Intangible damages, which are real and important, include destruction of biological life of the stream, reduced property values, and streams rendered undesirable for recreational uses.1 The major problems of mine drainage occur in the anthracite and bituminous coal regions in Appalachia. However, many of the western mining states have significant mine drainage problems in specific areas, but the overall problem is not as great as in the eastern states.

Jan 1, 1970

By R. C. Wilmoth, R. D. Hill, R. B. Scott

A cost breakdown is given for reclamation and mine drainage abatement conducted by the Federal Water Quality Administration's demonstration project near Elkins, W. Va. Costs for construction of control measures have been developed and include backfilling strip mines, sealing subsidence areas, reconstructing stream channels, and installing mine seals to prevent the entrance of water and air.

Jan 1, 1973

By Taner Sumer, H Altay Guvenir

Fragmentation in rock quarries is tried to be achieved by changing the specific charge, drill pattern and bore hole diameters by different experts. This paper is a brief summary consisting of the utilization of practical experiences of the other group on cost optimization procedure that takes into account blasting, transportation and crushing as a whole process and optimize the cost by defining the optimum gelatin based explosives to be used as a main primer of anfo in three different limestone and granite quarries, with similar rock characteristics.

Jan 1, 1993

By L. P. (Les) Haldane

Building a small underground coal mine is a risky endeavor, especially in the recent economic environment. ARCO's Mt. Gunnison No. 1 Mine, located in western Colorado, was designed and built as a small expandable speculation mine with initial production to be sold on the spot market, so it was very important to minimize capital exposure. This mine, operated by West Elk Coal Company, a subsidiary of Anaconda Minerals, was successfully built under budget at $35 million, and has been operating successfully since completion of construction in late 1982. The initial planning phase of a project is extremely important for testing the economic and technical feasibility of a proposal. The construction phase, by contrast, carries with it significant cost and quality risks which can relate to long-term economic and operating problems and therefore directly affect the viability of the project. This paper discusses several different aspects of the cost overrun risk involved in building an underground coal mine, and how attempts were made to minimize these risks during construction of the Mt. Gunnison Mine. Good people, construction planning, and execution are essential factors in assuring a quality, cost-effective project, with corresponding risk minimization during the construction phase and long term favorable implications for the operating phase.

Jan 1, 1985

By John Popovich

The MICON RokLok binder system including component and consolidation processes and safety and its first aide are described. The implementation procedures and selection of injection parameters are discussed. Finally a case example of recovering a 30-ft. long roof fall in mainline haulage entry is used to illustrate the economic potential of preventive measures by RokLok injection.

Jan 1, 2001

Whilst decisions to commit projects have traditionally been heavily influenced by hurdle rates for d.c.f. analysis, it is suggested that evaluation of competitors' costs may be a desirable additional tool.The MICAS system developed over the past four years is described. This computer system uses standard costs modified by District and Mine factors to allow estimation of individual mine costs. The data base contains more than 15,000 items of data and more than 6000 costs are calculated.Recent applications include use for competitive analysis, predictive analysis, statistical analysis, and comparative assessments with scopes ranging from a few mines to the whole Australian export industry. Some areas where care is necessary are outlined and potential further uses are discussed.

Jan 1, 1985

By Anderson Pereira

SORM 3plus (SORM = Superfast Optical Roughness Measurement) is a system enabling online measurement of roughness parameters during continuous strip processing. Increased requirements for new materials and more complex components call for ever increasing process safety. The roughness parameters are important quality features of uncoated and surface refined strips. The traditional method of measurement involves using a mechanical stylus based instrument. For this purpose the operator must stop the production line or samples are taken from the end of the coil and measurements are made offline in the lab. SORM 3plus, however, is a non-contact, online surface roughness measurement system that can be used for metallic and many non-metallic surfaces at strip speeds of up to 2400 m/min. The surface roughness data are stored in the system computer, displayed to the operator and if needed are fed into a higher-level network. The operator is alerted, if the limited values preset by him are exceeded or if any changes within the line will put at risk the production process. SORM 3plus calculates the roughness parameters as defined in the standards, such as the arithmetic average roughness (Ra) and the peak count (RPc).

Oct 8, 2019

By J. A. Herbst, A. E. Oblad, Y. C. Lo

The major cost in comminution is energy consumption, which can be as high as 50% of the operating cost. Improvements in plant operations have resulted in up to a 15% reduction in energy usage (kw-hr/t). These improvements have been made through the optimization of grinding efficiency and the use of expert model-based control systems. Optimization involves the determination of the levels of the critical-operating conditions that result in the most efficient breakage of ore in the mill. These optimal levels are identified through plant/laboratory test work and through computer simulation using advanced process models. Model-based expert control achieves the maximum performance from the grinding circuit by identifying the characteristics of the ore in the mill with an optimal on-line estimator. Using this information, the control system dynamically determines the operating point that will yield the optimal performance. Two industrial applications of grinding-circuit optimization and model-based control are presented to demonstrate the power of this new technology.

Jan 1, 1997

By V. C. Lo

The major cost in comminution is energy consumption, which can be as high as 50 percent of the operating cost. Improvements in plant operations have resulted in up to a 15-percent reduction in energy usage (kwh/t). These improvements have been made through optimization of grinding efficiency and use of expert model-based control systems. Optimization involves the determination of the levels of the critical operating conditions that result in the most efficient breakage of ore in the mill. These optimal levels are identified through plant/laboratory testwork and computer simulation using advanced process models. Model-based expert control achieves the maximum performance from the grinding circuit by identifying the characteristics of the ore in the mill with an optimal on-line estimator. Using this information, the control system dynamically determines the operating point that will yield the optimal performance. Two industrial applications of grinding circuit optimization and model-based control are presented to demonstrate the power of this new technology.

Jan 1, 1995