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By M. Fornaro, E. Lovera, I. Sacerdote

"The analysis of the mining laws of the different European States reveals big diversities and, often, remarkable complications. This is due, firstly, to the history and culture of different States and, secondly, to the assets of natural resources. It is therefore difficult to find a common line between the text of the various mining laws, but it can be observed that nearly all the States distinguish the mining resources in two categories: the materials whose importance is considered strategic belong to the first category; in the second category the materials whose importance (above all economic) is mainly local are comprised. The paper, analysing in detail the planning procedures in some important Countries, investigates the possible perspectives of arranging some guide-lines for a correct approach to the sustainable exploitation planning/programming of mineral resources (with particular reference to "quarry" materials, such as aggregates), considering both the environment protection and the production needs."

Jan 1, 2005

By R. A. Jankowsi, S. K. Ruggieri

Airborne respirable dust levels on longwalls can be reduced if operators approach the dust control problem in a logical and fundamental manner. This can be accomplished through the proper application and continued use of effective dust control techniques. The Bureau of Mines is currently assessing the effectiveness of longwall dust control techniques in use today to provide mine operators with guidelines for selecting the most appropriate control technology. This paper presents a fundamental approach to the problem of shearer dust control. Three dust control techniques to be discussed are: deep cutting/increased pick penetration for reducing the amount of respirable dust generated; drum water sprays/improved water supply system to suppress the amount of airborne respirable dust; and improved external water spray system, the "shearer-clearer," to push the dust close to the face. The techniques have been evaluated in field trials and have been shown to be both practical and effective in applications to control shearer generated dust.

Jan 6, 1985

By P. Venkatsubramanian, D. R. Maneval

An insufficient hydrologic data base exists for most large and small coal basins in Alaska owing to the lack of need in the past to collect data. The runoff process is insufficiently understood which is complicated by specifically northern phenomenon, and the lack of understanding of hydrologic relationships in permafrost environment. This paper presents an understanding of the hydrologic effects of frozen ground and presents methods by which the influence of surface mining upon the hydrologic balance can be analyzed.

Jan 1, 1987

By S. Rideout

As Assistant Director for Program Support for the Office of Surface Mining Reclamation and Enforcement (OSM), a bureau of the U.S. Department of the Interior, I am responsible for the regulatory and abandoned mine land programs under the Surface Mining Control and Reclamation Act of 1977, which governs the environmental impacts of coal mining. My perspective is influenced by my current position and my previous positions in government and private industry. Sustainability is a cooperative effort of many parties and can only be achieved if each assumes their responsibilities for making it happen. I will highlight some of my thoughts on the role of government in achieving sustainability in the mining arena.

Jan 1, 2007

By Roshan B. Bhappu

Integrating a research and development department into an engineering company's corporate structure can be rewarding to the engineering division, the R&D group, and, most of all, the company's clients. Actually, the R&D department is a logical extension of the conventional processing group within an engineering organization-but the R&D group provides services as needed to the engineering department while it is carrying out regular testing, pilot plant, and preliminary feasibility studies. Backup Services Provided With an R&D group, the engineering division does not need a process engineering group as such. The R&D group provides project backup services for feasibility studies, preliminary and detailed engineering, construction, and startup. The R&D group, in turn, benefits from its close association with project engineers, draftsmen, estimators, and computer capabilities in the engineering division. The client also benefits from the arrangement because R&D and engineering skills are available to both departments on an as-needed basis without standby eost. To handle the integrated responsibility of R&D projects, as well as conceptual design and preliminary feasibility studies, the R&D staff must be carefully selected. These research engineers should: • have a good background in plant practice as a mill superintendent or chief metallurgist; • be capable of organizing and supervising a testing program or a pilot plant campaign; •be innovative and willing to accept new ideas and concepts; • be able to translate lab test results into a workable flowsheet through sound conceptual design and feasibility studies; and •be able to communicate with clients. In short, the R&D engineer must be a jack of all process-engineering trades to successfully take a project from concept to operating reality. Engineers in a metallurgical R&D organization should have experience in mining and processing all types of

Jan 10, 1980

Currently the challenge that our society faces is to combine the economic activity for the continuously increasing needs of our expanding population with the necessary environmental integrity and the humanistic social concerns. In this paper, the methodologies that should be applied by the progressive mining industry in order to fall within the frame of the sustainable development are summarized. The Sappes project, an advanced gold mining project in north-eastern Greece, is presented together with the approaches adopted by Thrace Minerals S.A.

Jan 1, 2003

By John C. Franklin

INTRODUCTION Alpha-emitting radon daughter products are a recognized health hazard contributing to the development of lung cancer in persons exposed to excessive concentrations over an extended period. The primary control technique used by the mining industry is dilution with fresh air. Because the uranium is deposited in porous sandstone in most U.S. mines, the control of this hazard with dilution requires excessive volumes of air. As the mines become larger and deeper, the cost for ventilation becomes a major expenditure for the mining industry Most mines are maintaining levels of radon daughters lower than required by law but to maintain these present levels the mining companies are going to be drilling more vent holes or using other control techniques as the mine expands. These control techniques are being investigated by the U.S. Bureau of Mines to determine their effectiveness, cost, and safety for underground use. [Instrumentation] The Bureau's early research used batch sampling of both radon and radon daughters for determining the concentrations. In both cases it was determined that batch sampling did not give a complete understanding of what was happening to the concentrations. Therefore, continuous monitoring systems were developed for both. A continuous flow-through radon monitor was developed by the Bureau (Franklin, et al.., 1976) using a modified Lucas flask mounted on a photo-multiplier-tube (PMT). The air was filtered twice prior to entering the flask to remove dust, diesel smoke, moisture, and radon daughters. The signal from the PMT was then inverted, shaped, and driven to a data acquisition system (DAS) which accumulated the signals. The DAS has two comparators for setting the scan time and interval, a 24-hour clock with Julian date, a printer, and a perforated paper tape punch. Sampling time is determined by the type of experiment being conducted. Our normal sampling time is one 10-minute scan every 15 minutes, but could be set as low as one scan every minute or as long as a 16-minute scan every 167 minutes. There are two models of the DAS. One is a 10-channel system and the other a 30-channel system. On a 10channel system normally 6 channels are used for radon and radon daughters and the other four channels are used for temperature, absolute pressure, air velocity, and relative humidity as described by McVey (1977). Figure 1 shows a scan of five channels monitoring the radon concentration from intake to exhaust in a stope for a non-work day. If the radon concentration stayed this constant during work days, then continuous monitoring would not be necessary. [ ] Droullard (1977) developed a continuous alpha-beta monitor. This monitor has been modified so that it can be used with the DAS previously mentioned. Control Techniques The U.S. Bureau of Mines has conducted research in controlling airborne radon/radon daughter for 10 years. Major efforts have been conducted in sealing the rock to prevent the release of radon, bulkheading to seal nonproductive areas, backfilling with classified mill tailings, and positive pressure ventilation. Also, tests have been conducted to determine the mining cycles contribution to the radon problem. Surveys One stope with two intakes and one exhaust was continuously monitored to determine the effects of blasting, mucking, and drilling on the airborne radon concentrations (Franklin, et al., 1976). Two other detectors were located inside the stope which were close to the mining activity. In this stope no appreciable change in radon was observed during drilling holes for blasting and roofbolts. This study showed increases up to 40 percent in radon for slushing in the exhaust drift. The radon remained high and very eratic during slushing, as can

Jan 1, 1981

By Keith G. Wallace, Daniel J. Brunner

The traditional approach to mine ventilation planning involved making estimates of airflows, including leakage routes, and summing the corresponding pressure drops along consecutive paths in order to determine the fan pressures required. This methodology changed completely with the availability of computers. Mainframe digital computers began to be used for mine ventilation network analysis in the mid-1960's. Their use spread rapidly throughout the world in the 1970's. Mainframe machines were employed owing to the need for high speed numerical procedures and substantial storage requirements. However, during the past decade, the growing availability of low cost but powerful microcomputers has allowed the development of net- work analysis programs that can handle ventilation systems of hundreds of branches, and which can produce results within a few minutes. This paper discusses recent advances in software and hardware development specific to mine ventilation planning. Software developments include interactive data and output manipulation, graphical representation of output, internal checks on input parameters to preset ranges and subroutines which calculate the gas distribution throughout the network from known gas sources. Hardware advances have led to significant increases in memory to facilitate the analysis of large ventilation models, math co-processor chips which greatly shorten run times, and plotter hardware for graphical output displays. Recent software developments make it possible to graphically display output on printers faster than on standard plotters.

Jan 1, 1989

By S. Behl

In the selective flocculation process, polymers with specific functional groups can yield highly selective adsorption and, therefore, high separation efficiency. Selectivity in polymer adsorption may also be attained by specific additives that inhibit the adsorption of the flocculant on some solid surfaces but not on others. Generally, these additives have a different chemical nature than the flocculant. In this study, the lower molecular weight fraction of the flocculant was successfully evaluated as a site blocking agent, leading to higher separation efficiency than obtained otherwise.

Jan 1, 1993

By C. D. Secrest

Visiting Spring Canyon, a historic coal mining district near Helper, Utah, I was impressed by the great accomplishments that had taken place there. A tour book of the region tells of a period that began in the early 1900's, when the land was still very much the Old West, when settlers lived out their lives in coal company towns and produced a resource that was to build a nation (Cunningham, F., 1990). Between 1912 and the early 1970's, 11 mines had come and gone in that narrow canyon less than 15 kilometers long. Spring Canyon is a historic district now, but I could not dwell too long on the richness of its history. I was there to look for evidence of PCBs.

Jan 1, 1993

By J. E. Wennen

Screens serve several important functions in CIL and CIP processes for gold extraction. One important screen application known as interstage screening allows slurry to be continuously transfered through a series of CIL or CIP tanks while retaining activated carbon in the tank. In some cases, this has been accomplished by using airlifts to carry slurry containing activated carbon to an external screen which separates carbon as oversize and returns it to the tank by gravity. The undersize slurry advances to the subsequent tank. More recently this has been accomplished using launder screens and Kambalda type screens. These are essentially static screens that rely on air blasts or mechanical sweepers to clear carbon away from the screen surfaces.

Jan 1, 1998

By J. Luo

A major design problem for upper seam longwall gate roads that are to be constructed in a multi-seam environment is to predict the effects of stress field changes created by interaction. To quantify these effects, case study data were analyzed to develop empirical stress transfer relationships between seams for both longwall and room and pillar mining. Data analysis showed vertical movement and roof characterization in the upper seam to be controlling factors in damage prediction and, therefore, gate road planning and design. CMRR (Coal Mine Roof Rating) was correlated with the multi-seam roof characterization systems previously used. A WINDOWS-based software package named UGLY (Upperseam Gateroad Longwall Stability) was developed. Results from selected case studies were correlated with upper seam stress predictions.

Jan 1, 1997

By James L. Patton

Automation of mining increases the productivity of labor, thereby reducing the unit cost of labor. Such cost constitutes the largest portion of the direct or variable costs of producing coal. Therefore, any increase in productivity directly reduces variable cost. The large investment in mechanical equipment carries with it the burden of increased fixed charges. As the proportion of fixed cost to the total cost increases, the effects on the cost of production changes are amplified. Therefore, equipment must be fully utilized at all times. Averaged fixed costs rise with any decline in production. Such a situation forces coal companies to seek every means of main¬taining full production. Figure I will reflect the story on the relationship of production to cost.

Jan 1, 1962

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 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 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 M. B. Mirza, W. A. Sadik, B. T. Stanley

This paper presents the ventilation design for an underground testing facility in a salt medium. The under-ground workings consist of two 3.6 m-diam (12 ft-diam) watertight shafts and about 1830 m (6000 ft) of drifting. These facilities are designed to provide access for an in situ testing of a salt horizon in which a variety of hazardous and nonhazardous materials could be temporarily stored or permanently deposited. The ventilation system includes a design basis for gassy mine conditions and provides for the option of bulk air cooling and heating.

Jan 1, 1987

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 K. A. Grace, D. E. Ranta

The application of geology does not cease with the discovery and delineation of a mineral resource, but continues in the calculation of the economic parameters that determine reserves. Reserve determination, reduced to essentials, is the determination of the cost of production of a mineral commodity from a resource. This cost comprises mining, processing, waste disposal, reclamation and marketing costs. Geological input is vital in the calculation of the individual cost parameters from mining to reclamation, and even has same impact on marketing. Geology thus has a critical role in the determination of reserves.

Jan 1, 1992