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By Douglas A. Sloan

Who would believe that young elementary school children could understand something as complex as the mining industry? THE CHALLENGE The challenge of accomplishing this is tremendous. An examination of Canadian school children indicated that they knew very little about the world of work in general, and hardly anything about the mineral resource industry in particular. It calls to mind the story about two youngsters who decided to play house. The little girl played her role well as she went about the house doing things she had watched her mother do every day. When it was the little boy's turn, he grabbed his lunch, waved goodbye to his "wife", jumped on his bicycle and pedalled furiously down to the end of the driveway -- where he stopped. The youngster explained that he saw his dad go out of the driveway each morning, but he didn't know where he went, or what he did on the job. When you stop to consider the number of families today with two working parents, you can begin to appreciate the importance of the opportunities for role identity provided by this project.

Jan 1, 1979

By Timothy F. Markey, Brian C. Strohm

This paper presents a case study which applies risk assessment techniques in evaluating potential environmental problems associated with past waste disposal practices at a 65 acre non-ferrous metals and metal alloys manufacturing facility. Waste management activities at the site involved a number of surface impoundments for gangue material, neutralized acid rinse waters, acid rinse sludges, demolition debris, storm water runoff, stockpiled ores, and a permitted residual waste landfill. As a result of these activities, the She contained 9 identifiable waste management areas impacted by over 35 potentially hazardous chemicals and metals. Extensive environmental data obtained from investigations at the Site revealed heavy metal and volatile organic chemical contamination in various environmental media. These data were utilized to evaluate potential risks to human health and the environment. The human health risk assessment estimated potential health risks to workers, residents, and Site trespassers under current and expected future uses of the Site. Areas of the Site were identified which were considered to present potential health concerns under the various exposure scenarios. Results from the human health risk assessment were utilized to develop cost effective risk based soil remediation goals protective of the public health and environment.

Jan 1, 1992

By L. M. Pruett

The Arizona Legislature is currently in the process of considering mined land reclamation legislation in the 1994 legislative session. A bipartisan legislative study committee has drafted proposed mined land legislation. The committee has attempted to craft legislation that is appropriate for the unique conditions in Arizona. Existing Arizona and federal laws and regulations extensively regulate the environmental performance of mines in the state to protect public health, safety and the environment. The proposed mined land reclamation legislation does not replace or duplicate these statutory provisions relating to environmental protection. Instead, the purpose of the proposed legislation is to provide for the reclamation of land that is being mined and to fill the gap in existing laws by requiring the reclamation of land that currently is being mined or that has been mined since 1986 to provide for future land use. The legislation would require an operator to submit a reclamation plan describing the exploration operations, mining operations, post-mining land use and the proposed reclamation measures for review by a state agency. Financial assurance also would be required in an amount such that a third party could complete the approved reclamation measures. Arizona's mined land reclamation legislation would recognize Arizona's leading role in hard rock mining and emphasize the mining industry's economic importance to Arizona and the nation. Because mining operations necessarily require disturbing the surface of the earth to extract valuable minerals, reclamation requirements would be adapted to different conditions and would vary depending on site-specific conditions and on the commodity being mined. The current proposal does not identify the state agency that will administer the mined land reclamation program and approve reclamation plans, substantial changes to plans, and transfers of reclamation plans to other operators.

Jan 1, 1994

By Kalman N. Isaacs

Aerial photography is a recognized and integral part of the search for petroleum and for the metallic ores, but its application lags seriously; in the search for the industrial minerals This is, in all probability, a result of the relatively stringent economics of the various industrial mineral industries. The oil and mining companies (particularly the oil companies) can afford generous exploration budgets and thus can experiment with unorthodox approaches such as photogeology. The industrial mineral industry is more restricted, and up to now has relied on less sophisticated methods of exploration. The industrial minerals have been generally defined as those materials extracted from the earth that are neither metals, metallic ores, fuels, nor ground water. Any group chat must be defined in such a negative manner, by citing the things that they do not include, must in themselves be extremely diverse in character. This is truly the case for the industrial minerals; the full list of industrial minerals is incredibly long and tends to increase year by year.

Jan 1, 1964

By Kailash Narayan

Atlantic Richfield Company began operating a commercial uranium solution mining project in April, 1975 in Live Oak County, 10 miles southwest of the town of George West (Figure 1). The operation is designed to produce 250,000 pounds of U303 per year and is jointly owned by Atlantic Richfield Company, Dalco and U. S. Steel. The proprietary process employed in this operation consists of injecting an alkaline leaching solution into the ore-bearing formation through a pattern of injection wells. The uranium-bearing solution is then removed through producing wells using submersible pumps in central production wells. The produced solution is pumped through a pipeline to the plant area where the uranium is extracted. The barren solution is refurbished and returned to the pattern area for reinjection. The injection field and plant site are located in the drainage of Spring Creek, a small intermittent stream tributary to the Nueces River. Land use in the area is primarily agricultural -- cattle ranching and farming -- but several producing gas fields are present in the areas as well.

Jan 1, 1976

By F. C. Turin, T. L. Friend, A. G. Mayton, J. S. Jaspal, W. J. Wiehagen

This paper describes the serious injuries that have occurred to bulldozer operators working at domestic coal, metal and nonmetal mines in the United States. A serious injury is defined as one that results in either a fatality or in lost work time. Examined were 873 injury records compiled by the Mine Safety and Health Administration (MSHA). The time period covered was 1988 through 1997. These injuries resulted in 18 fatalities and 31,866 lost work days. All of these injuries occurred to dozer operators while they were performing common production tasks. An injury classification system was developed to code the narrative information that describes the circumstances surrounding the injuries. Jolts and jars accounted, for 604 or 70% of the serious injuries to bulldozer operators, and jolts and jars accounted for 75% of the workdays lost. Vertical jars comprised the largest set (354 incidents) of jolting and jarring injuries. In more than half of these incidents, the operator was backing up the dozer. Working near an edge carries significant risk for fatal injuries. Of 116 incidents where the dozer fell over an edge, rolled over or fell into a hidden void, 14 (12%) resulted in fatal injuries. In cases where the dozer operator either jumped or was thrown out of the cab in a fallover or rollover, seven out of 17 of the operators were killed. This study finds that further reductions in injury risk would require more widespread use of seat belts; consideration (and maintenance) of the seat and seat suspension systems that might reduce injury risk from jolts and jars; research interventions to assess the effect of alternative engineering designs to dampen or isolate the effects of shock and vibration; and continued attention to skilled performance, i.e., the integration of hazard awareness, recognition and response with dozer operational skills.

Jan 1, 2003

By Thomas P. Goslin

T e mechanization of industry to reduce labor costs and to improve product quality is affecting he scale industry as it has affected many other industries. With increased emphasis on higher production rates many operators are experiencing difficulty in overcoming production problems where weight is a factor. Unfortunately, the scale industry has not shown the development over the last twenty-five years that other instrument industries have. For centuries the balance scale has been the standard and the workhorse of most weighing operations. In recent years considerable effort has been applied to designs to make balance scales more acceptable to industries employing automatic or semi-automatic processes. For the most part the designers have not attempted to replace the basic scale but toautomate functions of material handling and human judgement. Modern dump scales, for example, will accept material from a conveyor until a preset amount of material is on the scale, At this time the scale turns off the conveyor, dumps the load of material and repeats the operation with any desired timing. These improvements have helped industry. Even the scale observer has been replaced with devices which observe the scale reading and operate on weighed objects according to their weights. In spite of' the application of automation to the material handling, the balance scale has not been completely satisfactory. One reason for this is fairly evident when one considers the construction of the scales. Inherently, they are slow devices because of the inertia of the beams. The beam scale, primarily a static measuring device, is at the best limited to slow dynamic measurements.

Jan 1, 1958

By A. A. Davis

The decade of the 70?s saw a series of landmark environmental resource programs enacted by the Congress. Many states followed suit, so that by the end of the decade air quality, water pollution, and the conservation of other natural resources, including minerals, were the subject of a wide-ranging body of laws, policies, regulations, and procedures. Many of the actions required or permitted by this rule-making involved areas for which adequate information and substantial experience were not available. Moreover, goals and objectives were sometimes established which were enormously difficult to achieve technically, or of such formidable expense as to cause concern about their consequences in the marketplace. It is therefore hardly surprising that one product of all this activity has been a mass of litigation. Court dockets are crowded with suits and counter-suits involving both substantive and procedural aspects of environmental protection. Indeed, it is probably fair to say that the volume and range of environmentally-related disputes brought before the courts parallels that generated by the civil rights movement a decade ago. There were also some new dimensions to the environmental movement. For the first time, the national environmental policy act required agencies to prepare environmental impact statements when proposed projects or activities would have substantial impacts on environmental resources. Another requirement of many of the new programs mandated meaningful citizen participation in public decision-making. Here, as elsewhere, the purpose was admirable, but guidelines were vague, and the result often was inaction, polarization, and litigation.

Jan 1, 1986

By R. D. Herron

Mining coal under deep cover conditions is certainly the proper phrase to use in describing one of our newest operations. Located in the southwest corner of Virginia is this operation which is the Beatrice Mine of the Beatrice Pocahontas Company, a joint venture of Republic Steel Corporation and Island Creek Coal Company. The mine is working in the No. 3 Pocahontas seam in an assigned area of over 9500 acres containing over 60 million tons of recoverable, high quality, low volatile coal. The site of the mine opening was at Keen Mountain, Virginia, where the seam lay 1350 feet below the surface. This depth, greater than anything attempted thus far in the coal industry on this continent, would pose some problems, we felt, with which we had not previously had to contend.

Jan 1, 1968

By Raúl Castro, Marco Vera, Alfonso Ovalle

The underground mining evolution for block cave mines in Chile and worldwide has made important strides in the last decades. Nonetheless, reserves determination in the initial stages of these types of projects—mainly for long-term planning—is not studied in as much detail as it should be, especially regarding the impact on the final value of the enterprise. Today, the first estimation of the size of a block cave mine, typically expressed in tons, tends to determine very large footprints and ore bodies. The resulting large-scale mine is obtained by applying the marginal cut-off grade (COG) to determine reserves. Yet, in many cases, it is possible to obtain an equal or higher benefit, extracting fewer reserves in less time, with a smaller active area, which significantly reduces the project’s uncertainty. To explore scenarios obtained by applying a higher marginal COG in the initial phases of the project, the Hill of Value methodology is used to estimate the net present value (NPV) in relation to the production rate and the COG. However, the application of this methodology considers certain simplifications that generate results which are not completely satisfactory in specific cases. This paper suggests an improvement of this method to obtain more reliable results regarding determination of a COG profile that will optimize the NPVof a block-cave project. The methodology was developed and applied in a massive polymetallic deposit with zinc, lead, and silver mineralization, corresponding to a real block caving project. The methodology provides NPV results that differ by approximately 15% in comparison to the real mine plan, while also being considerably simpler and faster to calculate. In summary, the proposed methodology provides a reasonable and fast procedure to estimate higher than marginal COG that increases the NPV of block cave mine projects.

By D. P. Bryan

The identification and-develop¬ment of new construction aggregate resources, the most common mineral mined, is an essential need in this country's growing urban areas. In developing an aggregate exploration program, a thorough geological identification of all potential aggregate resources in an area is still of primary importance but other factors have also to be considered. These include physical properties, end product application, transportation and mining costs, and local government regulations including zoning. The present major aggregate producers are most likely to develop these future resources and are in the best position to initiate comprehensive exploration programs.

Jan 1, 1987

By Kenneth K. Landes

Lake stone is a term currently applied to chemical and metallurgical grade limestone or dolomite that is brought down Lakes Michigan and Huron by large cargo vessels, mostly self-unloaders. This stone comes from 5 quarries, all in Michigan and all steel company owned. The volume in 1973 was over 34 million tons. The primary reasons for the large volume are the quantity and quality of the stone available, and the low delivery costs to lower lakes markets. The source rocks are Silurian and Devonian limestones and dolomites of exceptional purity. The regional dip of these formations is 50 to 60 feet per mile southerly toward the lowest point in the Michigan structural basin, which is near the center of the Southern Peninsula. Two of the 5 quarries, both high calcium limestone sources, are on Lake Huron in the northeastern part of the Southern Peninsula. The other three are in the Northern Peninsula; one at the northern end of Lake Michigan, and two on northern Lake Huron. The western quarry is in limestone, the other two in dolomite.

Jan 1, 1975

By B. M. Flohr

Railroads are cost competitive with trucks for hauls greater than 500 miles - WRONG. Today I will tell you about many rail movements of less than 100 miles throughout the country. Rail is a short haul transportation alternative you must consider. Transportation today is the largest controllable cost in the total cost of production of goods. In fact it is the one cost area where aggressive management, using new tools, can achieve significant reductions. You can't control the price of metals in the world market, you can't control labor rates since they are tied to industry norms, and the price of raw materials are relatively insensitive to specific price reductions to your firm. Transportation is the one area where major savings are now being realized. Sample Movements First, I will give you several examples of short haul rail moves to make you a believer that they do exist. Then I will show you the reasons why railroads suddenly "like" short hauls.

Jan 1, 1986

By John P. Norton

Microcystaline silica has been mined in Illinois from the Clear Creek formation since the turn of the century, especially in the area around Tamms in Alexander County, in the southernmost part of the state. Production of this silica, consumed mainly by the abrasives and coatings industries but also sought after for many filler/extender uses, has grown with the economy with several new applications overshadowing traditional markets in recent years. Such an important commodity was given the early attention of the Illinois State Geological Survey and a very complete report was issued in 1953 (Report of Investigations No. 166), authored by J. E. Lamar. The mining and processing of the silica ore has changed very little since the first reported production in 1906, although emphasis has been placed on the production of the finer sized grades to meet newer market requirements. Industrial Mineral Notes 40, published by the Illinois State Geological Survey in June 1970, describes a method by which a less than 1-micron fraction could be commercially produced from the readily available finest commercial grade presently being marketed (99% minus 10 microns). The finer grades exhibit to a lesser degree the reinforcement, high flatting efficiency, thickening and dry brightness properties associated with the synthetically produced silicas. It is expected that the extremely fine grades of microcrystaline silica will become accepted in the markets that now use a combination of precipitated silica and less expensive extender/filler minerals such as kaolin or calcium carbonate.

Jan 1, 1976

By Syd S. Peng

The key design parameters of roof bolting using expansion - shell type support for underground coal mine roof support are bolt length, bolt spacing, installed load and anchorage capacity. Depending on the utilization of suspension effect or friction effect, the bolt length is dictated either by the distance between the roof surface and the first overlying strong strata encountered or the desired magnitude of reduction in bending stress at the roof surface, The current prevailing practices about the bolt spacing and installed load are that an initial torque of 125 - 170 ft-lbs is applied and the bolts are spaced at 4- or 5- ft. square grid pattern. This seems to be a rather broad generalization in view of the great geological variances which are expected in underground coal mines. A modest evaluation program to measure the effectiveness of current roof bolting practices is to monitor the load history of roof bolts during a complete mining cycle including the phases of room development and pillar robbing. The load history, when compared with the anchorage capacity of roof bolts determined by in-situ pull tests, will provide information for evaluating the installed load, the bolt spacing as well as the specifications for structural and anchorage characteristics of the bolt assemblies. This paper presents a case history of monitoring the complete load histories of roof bolts in an underground coal mine of Pittsburgh seam.

Jan 1, 1976

By T. V. Falkie

REMARKS OF DR. THOMAS V. FALKIE, DIRECTOR, BUREAU OF MINES, U.S. DEPARTMENT OF THE INTERIOR, BEFORE THE FALL MEETING OF THE SOCIETY OF MINING ENGINEERS, AIME, ACAPULCO, MEXICO, SEPTEMBER 23, 1974 This is a time of uncertainty on the world mineral scene. For some of the world's so-called "developed" countries, reserves and production of key minerals are running low. And, we have learned that the energy so essential in recovering and processing minerals can suddenly be in short supply. The prospects for a "no growth" situation in energy or mineral consumption are practically nil. Moreover, the world's economy is in flux, casting doubt on whether traditional mineral customers will continue to be able to buy, or for that matter, whether traditional suppliers of minerals will continue to sell. It is clear that the mineral situation is contributing to world inflationary pressures, which incidentally are most damaging to developing countries. So it is appropriate that SME members devote this session to the world mineral situation, and consider some of the opportunities and responsibilities that we will inevitably encounter as the future becomes the present. The opportunities, to me at least, are especially intriguing, I have the good fortune to be part of an organization that has an enormous capability and responsibility for dealing with mineral problems. The Interior Department's Bureaus, including the Bureau of Mines, have been around for a long time. They are. a prolific and reliable source of both mineral information and mineral technology.

Jan 1, 1974

By Hal McVey

"Philosophy" addresses the definition and assigning of importance to the marketing of by-products. Two examples, one in metals and the other in industrial minerals, explore prime product to by-product relationships. Relative revenues from all products illustrate the importance of by-products to economic feasibility. "Mechanics" takes a broad view of the types of marketing organizations that are applicable to individual circumstances in the marketplace. In-house marketing as well as agents, merchants and trading companies are outlined and discussed. Philosophy Definition Of Terms Philosophy Definition Of Terms The definition of terns for a paper such as this is generally a necessary but not-very-interesting exercise. However, in simply trying to clearly define the term "by-product" some interesting relationships between products arise and the line of demarcation between "product" and "by-product" often becomes obscure. The search for that distinction represents the philosophy portion of the title. A couple of definitions of philosophy can even help to set the tone for what follows. According to Webster, philosophy is : 1 Pursuit of wisdom. 2. A search for a general understanding of values and reality.

Jan 1, 1983

By G. T. Adel, J. D. Miller, C. L. Lin

In view of the success of recent laboratory studies using X-ray computed tomography (CT) to determine coal washability and with the availability of high-speed CT systems, it now seems possible to design an on-stream washability system for the control of coarse coal-cleaning circuits. Design features for such a system are examined and possible control strategies are discussed for different applications.

Jan 1, 1995

By R. W. Bartlett

Aeration curing, over- a long duration in wet- red stockpiles, shows promise as an affordable pretreatment method for oxidizing gold encapsulating sulfide minerals, and possibly organic matter, in low grade refractory ores. Following aeration pretreatment, the ore is reclaimed, neutralized, and cyanide leached by conventional practices. Large tonnages of subeconomic material, including mine stripping waste, may he converted into ore by this new technology. The results presented show that a successful application of this technology will likely require crushing to about -2 cm (-3/4 in.), followed by aeration in a wet stockpile for long periods, up m three years. Natural convection may he inadequate, hut forced air ventilation, at modest pressures and power consumption, is affordable.

Jan 1, 1991

By M. M. Hajdasinski

For decades, the internal rate of return (IRR) project-evaluation criterion has been under increasing criticism. Torries (1998a) defends the beleaguered criterion. He claims that, as a project-evaluation and ranking instrument, the IRR is as suitable as the net present value (NPV). Torries also maintains that using the IRR to rank projects does not require the incremental approach and introduces his own alternative ranking approach. This paper disputes Torries' pro-IRR arguments and demonstrates that the IRR is a theoretically flawed and operationally dysfunctional criterion whose true meaning has persistently been misinterpreted. In a forthcoming paper by the author it will be shown that Torries' IRR-based project-ranking approach is flawed as well.

Jan 1, 2000