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By Nellie E. Guernsey

The Call for Papers described the session as "Top down applications; management tools for decisions, planning, investment/finance, and negotiations." In order to attract papers, and know which ones to include as well as those to reject, it was necessary to (1) define the executive suite, (2) review what had been done in previous APCOM symposia, and (3) find out what's happening now, what isn't being done, and what can be predicted. To accomplish this, especially the third task, senior managers throughout the mineral industry were generous with their time in telephone and personal interviews. Five papers were selected for presentation at the symposium and inclusion in the proceedings; the content is divided between the Executive suite in the mineral industry and those elements which apply to any Executive Suite. The Executive Suite is the top portion of the organizational tri- angle (I), those to whom the managers of functional areas such as exploration, production, finance, and marketing report. The make-up and specific activities within an executive suite reflect the organization and culture of its corporation. As there is no typical corporation, there is no typical executive suite; however, those who work within the executive suite typically do not have day to day operational responsibilities and either are, or report to, the Chief Executive Officer.

Jan 1, 1989

By Steven Johnson

The regulatory landscape has changed considerably since the first passage of Oklahoma's land-reclamation requirements in 1968 (Open Cut Reclamation Act of 1968). The Oklahoma Legislature revised the reclamation requirements in 1971 with passage of the Mining Lands Reclamation Act. With the passage of this Act, the Legislature empowered the Oklahoma Department of Mines with jurisdiction for permitting and regulatory authority over non-coal (industrial-minerals) mining operations. This act required all operators to file with the State, through the Department of Mines, a written application for a permit to engage in non-coal mining. Each application consisted of a mining plan, which included location maps of the proposed mining area along with a reclamation plan for the area to be covered. Additionally, a reclamation bond is required prior to issuance of a permit to ensure that the site would be reclaimed. Since 1971, the Act has been amended to include public notification and public participation in the review process of any application. Also, the operator can request that the Department review the mining plan based on the Life Expectancy of the mine, instead of the original one-year plan (HB 1409 in 1993). Even though the operator is granted a mining plan tied to the "Life Expectancy" of the site, the permit is reviewed annually for compliance as required by law.

Jan 1, 1999

By H. A. D. Kirsten

The assessment of backfill as a support medium in gold mines has been based generally on its ability to reduce the amount of potential energy available to cause damaging rockbursts. While this regional support effect is very important, the methods of analysis commonly used to quantify it predict that, owing to the very compressible nature of the fill, the support provided in areas of small convergence will be negligible. This prediction, however, is contrary to the conditions observed in practice, namely that weak fill does provide a discernible beneficial effect. In addition to the regional support effect, several mechanisms of secondary support, particularly those applicable to areas of low convergence, are identified and discussed. These include the mechanism of deformation of the detached hangingwall beam, rotational and shear effects on bedding, joints and fractures, joint infill, the continuous support effect of the backfill under static and dynamic conditions, the preservation of the integrity of the hangingwall beam, and the potential modification of local stress fields. Confidence in the validity of some of these mechanisms is afforded by the results of theoretical investigations into the behaviour of backfill- supported stopes. The results dealt with are: ? the behaviour of the hangingwall as a beam on an elastic foundation; ? the behaviour of stope/backfill, modelling the surrounding rock as a jointed rock mass.

Jan 1, 1988

By A. M. Johnson

Although known primarily for native copper, the Keweenaw Peninsula of northern Michigan also has deposits of copper sulfide (chalcocite) ore. A number of small, but rich, deposits are present at relatively shallow depths near the base of a thick, steeply dipping sequence of volcanic and sedimentary rocks. Because much of the ore is fracture-controlled, the deposits appear to be ideal candidates for in-situ leaching. Fracture mapping from drill core and borehole logs coupled with borehole packer permeability tests are being applied to evaluate the suitability of the ore for in-situ leaching. A leaching scheme utilizing a bacterial-assisted ferric iron lixiviant is being tested at bench scale. A pilot scale test is being designed to evaluate the system in the field.

Jan 1, 1988

By William Priestley

IN THE manufacture of gun forgings and other steel parts that, in service, are subject to sudden high stresses and shocks, it is most desirable to use steel possessing the greatest toughness and ductility possible without sacrifice of strength. In order to obtain this condition, it is necessary to procure steel that shows the highest possible elongation and reduction of area without lowering the tensile strength and elastic limit. Proper heat treatment of the steel can control this condition within certain limits. When heat treatment has failed to produce the desired results, metallurgists have used steels containing molybdenum, zirconium, vanadium, chromium, tungsten, etc. The purpose of this paper is to describe a method by which these desired physical properties may be procured-by the elimination of certain impurities that inherently exist in steel made by the open-hearth process, and without the use of expensive alloys. DESIGN OF GUN FORGINGS In the manufacture of gun forgings, a certain elastic limit is fixed by the designer, and the walls of the gun are made of the proper thickness, allowing a suitable factor of safety for the high stresses and sudden shocks that occur during gun firing. The elastic strength of the gun is about 1.4 times the stress set up at any point along the bore of the gun during firing with the maximum powder charge.

Jan 12, 1921

By M. K. Larson, J. P. Dunford, E. G. Zahl, T. M. Brady

Researchers at the Spokane Research Laboratory of the National Institute for Occupational Safety and Health, Spokane, WA, have collaborated with three Western longwall coal mines in an on going effort to develop technologies that will aid in providing safe and stable working areas. The goal of the research described here is to develop a stress monitoring system that will provide immediate information to mine managers for making daily safety decisions as areas of poor ground are mined through. Initial work has focused on answering preliminary questions regarding the reliability and use of stress change patterns. Research is concentrated on monitoring horizontal stress because horizontal stress is transmitted over long distances through stiff strata, thus allowing an extended length of entry to be monitored. This paper presents an explanation of the concept, key results from field tests at two mine sites, and a proposed process for implementing a monitoring system. System design layouts, instrument use, data collection and interpretation methods, and processes to present findings to mine staff are described. Additional validation and correlation with actual failure mechanisms are required before this approach can be recommended at ongoing operations. However, initial results indicate that this approach shows promise in mines prone to bumps and roof falls associated with large stress changes. In particular, analyses of measured changes in horizontal stresses appear useful.

By N. B. Strydom

The data on heat stroke cases reported during the past five years were examined to determine the influence of age on the incidence of heat stroke. Relating the age distribution of these cases to that of the total number of Bantu mine workers showed clearly that the older men run a significantly higher risk of developing heat stroke than the younger men. Although the number of Bantu over 40 years of age in the industry is less than 10 per cent of the total they nevertheless accounted for 50 per cent of the fatal heat stroke and 25 per cent of the nonfatal heat stroke cases during the period under review. Age must, therefore, be recognised as a causal factor in heat stroke and the worker over 40 years of age should be allocated to work on surface, or in cool areas or to non-strenuous and supervisory tasks in hot areas.

By J. Nielen van der Merwe

The move toward partial pillar extraction versus full pillar extraction has necessitated a new approach to underground section stability. When pillars are mined too small to support the weight of the overburden, they will, in some cases, remain stable for a considerable period; in other cases, they will collapse unexpectedly and violently. There is no discernable difference between the pillar safety factors of the failed and stable cases. The explanation lies in the characteristics of the overburden layers. A method is proposed that recognizes the overburden characteristics in the evaluation of stability. Two stability factors are calculated: one for the pillars, the other for the overburden. Using this method, it is possible to make use of the bridging capabilities of overburden layers to prevent pillar collapse. It is possible to scientifically design partial pillar extraction layouts that will be safe. Using energy considerations, it is also possible to prevent violent failure of pillars.

Jan 5, 1999

By Chen Zhiquan

Author has exhaustively researched into soft ground through construction of a large open caisson on soft ground (muck) which weighs more than 4, 000 tons. To avoid any contingency during construction, we precompressed muck stratum with a sand cushion and consolidated it with sand piles before construction of the caisson. We made borehole surveyings and soil tests many times before and after ground treatment. Following the tracks of changes of the caisson at all stages of precasting, we surveyed a large number of data. On the basis of analysis of the data we changed the original construction plan of precasting in four stages and sinking in three stages into that of precasting in three stages and sinking in one stage. Through the practice of the whole caisson construction the author has advanced new theory of kinematic law for soil particles and the change's law for strength of muck during precompression of sand cushion and consolidation of sand piles.

Jan 1, 1991

By J. Donald Rimstidt, Jeanette K. Jerz

Acid mine drainage is a major environmental problem worldwide. A key to remediating this problem is understanding the rate and mechanisms of the complex, multistep pyrite oxidation reaction under geologically relevant conditions. Because many waste piles are not submerged, a large amount of pyrite oxidation actually occurs in air. We have designed a Barcroft-manometer reactor to measure the rate of pyrite oxidation in air as a function of relative humidity and oxygen partial pressure. The reactor consists of two chambers joined by a manometer. Each experiment occurs at constant temperature, initial oxygen partial pressure, and relative humidity, although these variable can be changed between runs. Oxygen consumption was measured and pyrite oxidation rates were calculated from those data. Initial data indicate that rate of pyrite oxidation by oxygen in humid air is much faster than the rate of oxidation by oxygen in solution. The rates determined by this study can be used to develop better remediation techniques for acidic mine waters.

Jan 1, 2000

By J. K. Phiri

Copper mining is the main activity in Zambia and is confined to the large scale operations, mainly on the Copperbelt. The Copperbelt covers an area of size l00km by 50 km with a total of 10 underground and 5 open-pit mines operated by Zambia Consolidated Copper Mines (ZCCM) Limited. Most of the operations in these mines involves drilling and blasting. The loading of broken materials is by both manual and mechanical operations. Among the many risk factors associated with mining on the Copperbelt, is the occurrence of Pneumoconiosis which in the recent past has become quite prevalent and thus an important occupational health hazard for the industry. This study was carried out with the aim of establishing trends of pneumoconiosis incidence through the annual data collected by Pneumoconiosis Medical and Research Bureau of the Ministry of Health in Zambia, so that a basis could be formed for future research work. The study covers over 1,000 certified cases of Pneumoconiosis between 1960 and 1990

Jan 1, 1993

By Hannan JC

Consent to develop and operate a new coal mine in New South Wales (NSW) will be conditional upon a number of environmental controls. In NSW, applications for any new major development associated with coal mining are determined by the Minister for Planning and Environment. The environ- mental conditions placed on the development consent, the coal mining lease and the approvals, and licences under the pollution control legislation amount to a substantial component of any new project's commissioning considerations. The nature, scale and location of projects and the principles of pollution control on which conditions of State Pollution Control Commission (SPCC) approvals are based have a considerable influence on project planning. The design, construction and operation of coal mines in NSW has been progressively modified over the past 15 years, to incorporate increasingly stringent requirements for environmental management. These requirements are in turn, a reflection of a greater community demand for environmental protection.

Jan 1, 1986

By Jouko Kallionen

Advanced Flotation Technology is the application driven design of flotation cells to achieve the optimum performance for each type and grind of flotation. This can be applied to roughers, scavengers, cleaners and specialty cells such as those to float hydrocyclone underflows in both primary and regrind circuits in order to reduce overgrinding. Standard, engineered, components are matched to provide mechanism design and cell dimensions for each case according to feed parameters and flotation type. Advances in process control have been achieved with high level controls and operator information data. This has gained a higher degree of understanding of cell operation and ore type being processed. Excellent results of this Advanced Flotation Technology in large scale porphyric copper ore have been achieved and designs through 7000 cu ft (200 m3) are currently available for high capacity concentrators. This paper will detail how flotation cells are more responsive to the exact requirements of the duty specified.

Jan 1, 1999

By W. M. Shaver, R. Letourneau, W. R. Dengler

Dynatec Mining Ltd. contracted to sink a 1500-m (4920 ft) concrete-lined shaft for Falconbridge Nickel Mines in Sudbury, Ontario, Canada. The shaft has an inside diameter of 6.3 m (20.5 ft) and is equipped with steel furnishings. Dynatec used the owner-supplied, 4.6-m (15.1 ft) diam, double-drum hoist to sink the shaft. For muck removal, 12.5¬t (13.8-st) buckets were used. The capacity of the concrete-¬placement buckets was 4.6 m3 (162.4 ft3). One of the unique features of the shaft sinking operation was the use of a two-¬boom, electric-hydraulic drill jumbo permanently mounted in the shaft sinking stage. An in-the-hole (ITH) drill was used to drill a 200-mm (8-in.) cut hole for the 4.8-m (16 ft), full face rounds. This paper describes the performance obtained with the electric-hydraulic drilling equipment and the high-capacity muck removal and concreting equipment.

Jan 1, 1994

By Mark Larson, Steve Iverson, Brian G. White

The authors hypothesize that excavation-induced extension fractures are caused by elastic shearing displacement that in turn causes tension oblique to a propagating shear zone. Such extension is manifested as tension on scales larger than that of microcracks. En echelon fracture patterns are a common result. FLAC modeling confirmed that localized tension is created near the corners of mine openings. In the model, tension was concentrated at the leading edge of a simulated fracture in a pattern that could promote the formation of an en echelon fracture. Particle Flow Code models confirm progressive formation of en echelon tensile failures with distance from an opening. The elastic displacements and the resulting fractures facilitate reduction in applied load at the expense of shear deformation and lateral dilation. Understanding the mechanics of fracture and deformation is vital for designing more effective ground support practices, a major objective of ground control research being conducted at the Spokane Research Laboratory of the National Institute for Occupational Safety and Health.

By Forrest T. Moyer

THIS CHAPTER of the Minerals Yearbook contains injury experience and related employment information for the coal-mining, coking, oil and gas, peat, and native asphalt industries in the United States for 1962. Injury experience is measured by the number of injuries sustained per million man-hours of exposure in each industry. No attempt has been made to combine these data and present rates reflecting the mineral-fuel industries because the hazards of the separate industries are not comparable. Tabulations showing the trend of injuries and employment for all mineral industries are presented in volume III of the Minerals Yearbook. COAL The injury-frequency rate for the coal-mining industry of the United States increased less than 2 percent, according to reports received by the Bureau of Mines. The number of fatal and nonfatal injuries per million man-hours in 1962 was 45.86, based on final data for anthracite mines and preliminary data for bituminous coal and lignite mines.

Jan 1, 1963

By R. V. Ramani

Managers need quality information for effective decision making. This demand, at the present time, is being fulfilled by the increased use of computers via information systems, decision support systems and management information systems. The idea of incorporating intelligence into computers to aid decision-makers has been evolving for over two decades. In recent years, significant progress is reported on applications to business and sciences. In engineering functions, the Artificial Intelligence approach that seems to have great potential is the application of Knowledge Based Systems. The primary objective of this paper is to identify domains in mining engineering where application of knowledge based systems could be beneficial. In- corporation of the expertise required during the analysis and interpretation stages of an engineering design problem through knowledge based systems is recognized as an area of significant benefit. To this end, the components of knowledge based systems for mine ventilation and strata control design are described. The potential applications and limitations of knowledge based systems are outlined.

Jan 1, 1987

By Walter Kauenhowen

GeRmany's crude-oil production during 1936 totaled 3,112,494 bbl., an increase of 5.2 per cent over the 3,007,711 bbl. produced in 1935. The official monthly production figures published in 1936 report only the individual production figures of the three old established fields, whereas since 1936 official reports combine the production of all other fields into one figure. According to these published data, and using a conversion factor of 1 metric ton equaling 7 bbl., the oil production of Germany in 1936 was as follows:

Jan 1, 1937

By M. Pantazidou

The wide use of chemical grouts, in combination with increasing environmental awareness, necessitates the evaluation of possible adverse effects if grout constituents may leak in groundwater. Acrylamide-based grouts are of particular interest, since the engineer has to balance the superior properties of these grouts and the known human health impacts of acrylamide. This paper identifies the properties of acrylamide that are required for the evaluation of its fate and transport in the subsurface and presents results of numerical simulations of acrylamide transport for a hypothetical tunneling application.

Jan 1, 2006

By AIME AIME

THE accompanying photograph: submitted by C. L. Bransford, assistant district manager of the Republic Steel Corp., in Birmingham. Ala., shows the remains of the old Tannehill blast furnaces, one of the first furnace plants in the South. They were built by Moses Stroup and operated during the Civil War period, when cannon balls were cast there. The record day's run of this furnace plant was said to be 30 tons of iron. The furnaces were fed by a water-wheel-operated bellows and used charcoal, a product of the neighboring forest. They were first owned and operated by the Pioneer Mining & Manufacturing Co., that later became the Republic Iron & Steel Cu., and subsequently the Republic Steel Corp. in that district.

Jan 1, 1936