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By Liu Cheng-si

Basing on a brief assessment of the conventional theory of ventilating air distribution, its methods of calculation and practical application, this paper makes an approach to the controllability of different aircourses of a ventilation network and further points out that it is possible for the positions of control to extent into the natural distribution subnetwork of the ventilation network, which was been long considered as a restricted zone. This important discovery makes the regulation of the ventilation system more flexible and diversified, thus attaining quantitative distribution of ventilating air as well as a cost benefit. Because it has been impossible to solve the problem mentioned above by conventional theory and its relevant methods of calculation, the author, based on applying graph theory on the structure, characteristics, and requirements of controllability of the ventilation network, presents a new controllable subgraph concept and the means for determining the rational quantity for control devices of the ventilation network. The solution of all the control alternatives and methods of obtaining all the parameters for the solution of various alternatives have been derived. The economic benefit and the optional positions of the control devices have also been approached. Specific calculation examples are a1 so included in this paper. Along with the conventional theory and its methods, it can be seen that the new theory presented makes a great change in the control aspects of the ventilation network, with the number of possible alternatives increasing in an astonishing manner. Among the alternatives, some may be safer, more economical or technologically superior than those obtained from conventional theory. Thus, the new theory may provide an immense improvement in the choice of a ventilation system.

Jan 1, 1987

By Kevin R. Burns, William A. Depree, John J. Jansky

This paper presents some of the work associated with the reduction of employee exposure to diesel and blasting contaminants at an underground salt mine. The purpose of the paper is to outline the procedures recommended in resolving the problems associated with these contaminants. The first stage consists of a complete mine ventilation survey. The purpose of the survey is to identify any problems in the mine. The survey consists of air quality, air quality and ventilating pressure measurements taken throughout the mine. After completing the survey, the information is analyzed to identify problem areas and the possible causes. All available solutions to reduce the levels of contaminants are then explored and evaluated for feasibility. The PSU Mine Ventilation Simulator is then used to accurately simulate possible changes to the ventilation system. These ventilation projections are a useful tool to illustrate to the company and union personnel the possible benefits of various ventilation changes. This paper will illustrate the phases involved in making important and sometimes expensive ventilation decisions. Through the cooperative efforts of MSHA, company and union personnel, the levels of contaminants have been reduced by approximately 200 percent. As a result of these ventilation improvements, the company can now safely increase production approximately 25 percent.

Jan 1, 1987

By J. H. Hill

The globalization of mineral markets and intense competition in downstream mineral-consuming industries such as transportation, agriculture, and construction are requiring raw materials suppliers to innovate, improve quality, invest in new technology, and control costs. Mineral specifications are becoming more refined, and pressure to improve products is felt from increasing numbers of competing producers, substitute materials, customers, and regulators. As a result, engineered mineral products are becoming more like manufactured ones in terms of cost structure, differentiation, and the importance of market driven, customer specific product development. Engineered mineral products are defined as those where the costs of refining and upgrading outweigh those of conventional mining activities (blasting, crushing, classification, haulage etc.), and where close control of physical and chemical parameters is required for customers' processing and manufacturing applications. This includes industrial minerals such as calcium carbonate, kaolin, mica, specialty oxides, talc, and some metal powders. It excludes most metals and bulk commodity materials such as gypsum, lime, sulfur, and soda ash. Engineered mineral products are utilized in common household goods, and are at the forefront of industrial materials engineering in plastics, ceramics, composites, glazes, coatings, and construction materials. As a group, they introduce interesting questions to the minerals firm. Advanced materials or basic? Diversify or specialize? What are the implications of advanced materials and for mineral markets, and most importantly, where can the producer look for long-term value, volume, and profits?

Jan 1, 1993

By Erick F. Weiland, John W. Lindemann

Introduction Minerals exploration is one step in the mining industry's task of providing raw materials to basic industries. The industry's provision of raw materials involves identifying and evaluating resources, converting them to reserves, and intelligent, economic exploitation of these reserves. The mineral process focuses on identification and evaluation. Reserves are ore bodies and ore bodies are, by definition, wasting assets. Therefore, if an adequate provision of raw materials to basic industry is to continue, these wasting assets (ore bodies) must be replaced with new or different reserves as current reserves are depleted. Minerals exploration is a geologic problem and is fundamentally deductive, flowing from the general to the specific. Past exploration methods and philosophy have amply supplied the resources to meet the demands of an industrial society. During the past decade, however, the framework where mineral resources were identified, defined, and evaluated has changed. Mineral explorationists no longer can rely solely on the successful past methods to provide the necessary resources for our complex society. Productive explorationists must effectively and efficiently use tools and procedures that will maximize exploration efforts. Past tools need not be abandoned, but should be critically reviewed and revised in light of current scientific knowledge and technical advances. Future explorationists will view their craft not as a single discipline, but as a thoughtful integration of geophysics, geochemistry, and geostatistics for solving interrelated problems. This integration of the geosciences will lead to successful mineral exploration. Not only will the productive explorationist generate new information, he will master the use of existing data for identifying and evaluating a mineral resource. The mineral exploration process consists of incentives, ideas, finance, area, staff, time, and luck. The exploration process that stems from the interaction of these elements has three stages, each bound by a major decision point. They are selection, reconnaissance, and definition. Subsequent evaluation and exploitation phases are considered more the function of mining engineers than the exploration geologist. Mineral exploration endeavors that have been productive have three attributes fundamental to success: commitment, competence, and persistence. Commitment Commitment is believing that exploring for mineral resources is worth performing. While the mining industry is the focus of this commitment, government and society must also be committed to the concept of mineral reserve identification through exploration activity. Government demonstrates its commitment by providing access to land for exploration and, if it is successful, exploitation can take place. Realistic legislation relating to taxation, land use, reclamation, and environmental constraints is indicative of government commitment to intelligent resource use. The public must come to terms with mineral resource evaluation and extraction. Without some form of commitment from the public, availability of mineral resources vital to basic industry will be largely in the control of a foreign and potentially unstable mining industry. Commitment to a mineral resource identification-evaluation-extraction system must be shared equally by government, society, and the minerals industry. The scope and direction of this commitment varies, with the industry's commitment to explore for mineral resources being the most apparent. Industry commitment is the belief at all levels of exploration (from senior corporate executives to individual field and support staff) that exploration is worth performing, that exploration goals can be met, and that their particular organization is the best and the only group that can successfully accomplish the project. Commitment can be considered at three

Jan 11, 1983

By M. David Monroe

Getting the best match between truck and haul road requires examining the cost effects of many factors. Most mines use a bottom line measure based on cost per ton of material moved. This measure focuses on the two components of truck haulage cost per ton: productivity (or performance) and operating cost. For specific tasks, productivity can be measured or predicted using either field measurement or modeling. Individual tasks can be combined to provide a larger scale, longer term net figure for total mine output. True cost is more difficult to capture. Factors are time- and task-oriented and can be influenced by a summation of factors over a truck's lifetime. For example, "allocated" costs, such as owning (depreciation) and some repair costs, are spread over long periods. Items such as fuel and tires can be tied more directly to certain tasks. This article focuses on the more direct, task-oriented factors that affect truck productivity and cost. Major factors The relationship of haul roads and trucks means that each must be examined separately to isolate the most important factors affecting performance and cost. There are many factors but the most important are:

Jan 1, 1992

By Carrie Smith

In a major milestone for geoscience, the U.S. Geological Survey (USGS) has unveiled the Cooperative National Geologic Map, the most detailed national-scale geologic map of the country to date. The project offers a fresh, layered look at the rocks and sediments that make up the United States. For geologists, engineers and mining professionals, it provides both a technical achievement and a practical tool that will help shape future exploration and landuse decisions across the country. The new map provides a regional view of geology both on and beneath the Earth’s surface. Using different colors to represent rock types and sediments, it allows users to toggle through multiple layers, revealing for the first time the surficial and quaternary deposits that lie above the bedrock. “This is the first national map to include multiple layers of mapped geology, the first built to be easily updated as new maps are published, and the first to be delivered in a user-friendly online interface,” said Joseph Colgan, a USGS research geologist who led the development team. The Cooperative National Geologic Map is a culmination of more than a century of collaborative mapping between the USGS and the nation’s state geological surveys. More than 100 existing maps produced by state geological surveys and the USGS over the past 40 to 50 years were combined and standardized to create the national data set. During its three-year creation, the USGS prepared digital data, built the system to bring the maps together, developed the web interface and underwent a review and approval process. Through this process, decades of fieldwork, analysis and digital cartography were brought together to provide both national and local expertise.

Nov 1, 2025

By Norman Miskelly

Role of CRIRSCO CRIRSCO has an advisory and hopefully influential role in International Mineral Resource/Reserve Reporting Standards CRIRSCO also has a broad educational role CRIRSCO does NOT have a negotiating role CRIRSCO does NOT have a regulatory role

Jan 1, 2003

By T. Mudder, K. Harvey

The objectives for closure of a hard rock mine include minimizing long term environmental liability, attaining regulatory compliance, and maintaining geotechnical stability, while closing as cost-effectively as possible. Proper planning for closure should come during the feasibility study, design and permitting phases, and during operations as updates. The lack of a proper or updated closure plan can result in severe environmental and economic consequences. Effective mine closure is the result of a combination of innovative concepts, long-term commitments, and multi-party cooperation. The purpose of this paper is to discuss concepts, commitments, and cooperation as they relate to an effective closure plan.

Jan 1, 1999

By R. Mohr

Storm water runoff from mine facilities such as haul roads, waste disposal sites and ore bodies have become recognized as the primary facilities associated with non-point source drainage. Depending on the ore body, facility design and geographical setting, nonpoint source drainage can cause pollution impacts to local surface and ground water resources. Non-point source impacts from surface mine drainage have become an important regulatory issue for the mining industry. Implementing non-point source drainage control plans that prevent impacts to water resources can be accomplished cost-effectively with moderate labor requirements. Design considerations for plan development must incorporate parameters including contributing drainage area size, slope, flow velocity, vegetation characteristics and soil scour velocities. The success of non-point source drainage and erosion stabilization planning is based on implementing control measures that dissect drainage patterns, reduce flow velocities and disperse runoff towards sediment control sites. Interim and long-range drainage control measures should begin during exploration activities. Regulatory legislation addressing non-point source pollution sources was enacted as amendments to the Clean Water Act (CWA) in February 1987. The legislation required states to initiate non-point source pollution control programs.

Jan 1, 1991

By D. Kump

The Bullfrog Mine is an underground goldmine that uses the underhand-cut-and-fill mining method. The portal was established on June 18, 1991. Mining is expected to be completed by the summer of 1999. This paper starts by discussing what it took to get from nothing to 2000 tons-per-day backfill, and ends with a hindsight commentary on things that did and did not help.

Jan 1, 1999

By Mollie Hunt, William Riley, Russ Downer, Kate Willa Brown Requist, Víctor O. Tenorio, Geoffrey Gill

One of the first activities after returning to the Moon will be finding sources of water and materials for the construction of human settlements and other infrastructure. There is evidence of the existence of deposits in the bottom of craters at the South Polar region and in flat areas around. Based on geological data from the Moon, a block model representing a deposit or icy regolith has been defined in the vicinities of Shackleton Crater, with unique characteristics of shape, thickness, and water contents. A mine plan utilizing surface mine modeling software for ore extraction from an open pit- type of excavation to a delivery point near a water processing facility is proposed, with monthly, quarterly, and yearly schedules. Production results, dashboard charts and progress of the topographic changes are also presented.

Feb 1, 2024

By G. C. Anderson

The Cleveland Cliffs NOLA electronics and software upgrade is a Windows based system that simultaneously controls two Texas Nuclear NOLAs and associated sampling. It uses new spectrum analysis and algorithms to produce accurate, linear silica measurement with slurries that range from 5 through 50 percent solids. This linearity allows us to achieve a reproducible procedural calibration. The hardware consists of readily available shelf items, is extremely redundant and eliminates all NIM bus modules.

Jan 1, 2003

By Jan Reimann

Increasing individualization with smaller quantities, growing competition from low-wage countries, and the continuous drive towards digitalization are the challenges that industrial companies in high-wage countries must face. The example of the Flender One gearbox modular system demonstrates how consistent standardization and digitalization are the enablers for AI, and thus already enable new business models and business approaches today.

Feb 22, 2026

By P. Maraboutis

Extractive industry (mining and quarrying operations), as other industrial activities, is subject to environment protection laws, regulation and standards such as the Environmental Impact Assessment directive, Natura 2000, Habitats & Birds directive, Water Framework directive etc The European Commission (EC) is aim to strengthen the EU environmental legislation to improve the (environmental and human) safety of mining activities. The mineral processing and the management of the mining waste will be covered by the new amendment of the Seveso II Directive, by a Best Available Techniques reference document (BREF) describing the Best Available Techniques of mining waste management and a new directive on the mining waste management. At the same time initiatives as the environmental liability, the energy taxation for environmental reasons and the natural resources management policy, which will have a positive impact on the protection of the environment, will affect the extractive industry operation procedures.

Jan 1, 2002

By John C. Ferm

Although roof falls account for approximately half of the fatalities in underground coal mining, the factors that produce them are not clear. Mining methods can account for some, but in others the controlling factors are the geological setting in which the mining takes place. The present investigation was undertaken to determine the kinds of rocks that were most likely to produce roof problems. Such knowledge would be helpful to mine planning since rock samples can be obtained in advance of mining by core hole drilling. The investigation was undertaken in underground mines in the Pocahontas #3 seam in southern West Virginia and southwestern Virginia. The Pocahontas #3 is one of the most widespread in this region and is a major source of high quality metallurgical coal. There are at least ten very large mines in the area and many smaller ones. The region has a very long mining history and considerable experience has been gained in roof control problems. The study was conducted with the support of the U. S. Bureau of Mines.

Jan 1, 1978

By S. Borner Schweizer

An overview over SAM’s approach to assess corporate sustainability performance illustrates how sustainability challenges are linked to trends, assessment criteria and finally company performance. This process is exemplified with some general and industry specific criteria. Lastly, results of the Dow Jones Sustainability Assessment 2004 show a considerable gap between leading and average companies. Best practice examples demonstrate how lagging companies could improve their sustainability performance.

Jan 1, 2005

By G. L. Merritt

The implementation of the Surface Mining Control and Reclamation Act of 1977 (SMCRA) has evolved into one of the most complex environmental protection programs to come out of the late 1970's. The level of detail in the statute and the regulations have resulted in a rigid and complex set of requirements for the administration, permit-ting, inspection and enforcement of the program. In addition, the constant change of the federal program caused by regulatory changes, reorganization of the Office of Sur-face Mining Reclamation and Enforcement (OSMRE), ongoing litigation involving OSMRE, and the use of the budget to establish additional mandates on OSMRE and the State Regulatory Authorities have resulted in an unstable program. The instability of the program makes it extremely difficult for the States to implement their programs and to achieve the goals of SMCRA.

Jan 1, 1988

By A. Ghalambor

The objective of this investigation was to determine the sensitivity of three selected input parameters in the operational control of continuous bottom-fed thickeners used for the treatment of coal refuse slurries. The three variable parameters were "Feed Flow Rate," "Feed pH," and "Feed Solids Concentration." These three input parameters were studied under three polymeric conditions which were cationic polymer, anionic polymer, and a combination of cationic-anionic polymer. For each polymeric condition, two mathematical models were developed: one for overflow response, the other for underflow response. The combination polymers produced the best desired quality of overflow and underflow. For this polymeric condition, changes in the feed solids concentration was the most sensitive factor in the maintenance of the overflow quality, and the feed pH was the most sensitive factor for the maintenance of the underflow quality. The mathematical models generated a set of plots which would allow an operator to control and/or adjust any of the three variables to achieve optimum conditions.

Jan 1, 1989

By J. E. Stephens

US Borax began exploration in southeast Alaska in the summer of 1971 with a staff of two, Barry Watson and Jackie Stephens, based in Spokane, WA. After several years of prospect examinations in the islands west of Ketchikan, AK, and with the able assistance of prospector-pilot Kenny Eichner, Jackie Stephens proposed and organized a boat-based, helicopter-supported, stream sediment sampling program to explore the western contact of the Coast Range intrusive complex on the mainland. The rationale for this included: the extension of known mineral trends from Canada into southeastern Alaska along favorable geologic zones; the western contact area of the Coast Range intrusives with metasediments and metavolcanics was a favorable target for metals exploration as shown by numerous small prospects. Knowledge gained from mineral exploration of the island areas indicated that they were well mineralized, but already well explored, and that the known mineral potential was probably present in subeconomic quantities (Brooks, et al.). Publications of the US Bureau of Mines and other scientific agencies were gathered and every prospect within the southem southeastern Alaska area was plotted. This in itself lent a tremendous amount of knowledge to the total exploration program. US Borax's McLean Arm copper property on Prince of Wales Island was drilled and dropped while this compilation of data was proceeding. We found that many companies had followed one another around the island areas, but little or no exploration had been done on the west side of the Coast Range, and that many explorationists flatly stated that the west side of the Coast Range was barren of mineralization. In summary, although some of the shoreline and near shoreline areas of the mainland had been explored, no organized boat-helicopter exploration program had been done along the favorable western zone of the Coast Range Intrusive complex. We decided to use a boat as a floating hotel for the crews that were to be helicoptered into the back country from tidewater for our initial stream-sediment sampling program.

Jan 1, 1991

By Charles F. Herbert

Placer mining in Alaska had a desultory inception at Sumdum in 1869 and, during the years 1880 to 1896, received thin nourishment from the readily exhausted gold placers at Juneau and the longer- lived deposits in the Circle, Fortymile, and Rampart Districts. Finally, in 1897, the great Klondike discovery in Canada's Yukon Territory brought thousands of gold seekers to the Far North. These men, in successive, far-reaching gold rushes, found the large, rich gold deposits at Nome, Fairbanks, and Iditarod, as well as many smaller placers. The hectic rushes during the years from 1898 to 19 10 were comprised of hundreds, sometimes thousands, of "stampeders," as they were called. Since very many Alaskan creeks, from the crest of the Brooks Range in the north to the Pacific Ocean in the south, carry at least a few flakes of gold, there was ample seed to start a new stampede. Of the 100s of reported "strikes," nearly 50 became more or less important placer mining districts; by 1910 they had produced about 184.2 fine Mg (6.5 million fine oz) of gold; the all- time peak production year was 1906. A few of the miners and prospectors prospered, but the total value of all gold produced failed, by a wide margin, to cover the aggregate costs incurred by them in the undeveloped Territory of Alaska. On the other hand, the traders with their readily salable supplies of food, tools, and hardware and the freighters with their teams of dogs or horses and boats of all kinds profited throughout the era of stampede.

Jan 1, 1991