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By Laurence F. Kelley

This paper is one of a series being prepared by the United States Bureau of Mines on shaft-sinking methods and costs at individual operations in various mining districts of the United States. The methods and costs described herein are those of The Consolidation Coal Co. at one of its operations in the Tug River district, McDowell County, W. Va. ACKNOWLEDGMENT The author is indebted to Frank R. Lyon, vice-president, Thos. G. Fear, general manager of operations, and Chas. Enzian, chief engineer, of The Consolidation Coal Co., for valuable assistance and collaboration in the preparation of this paper. W. A. Cole, manager of the E. J. Longyear Development Co. furnished valuable data on methods and performance averages.

Jan 1, 1932

By J King, T Hunter, R Coleman

"The industry that supports operations and new projects is suffering a rapid decline in the currently severely curtailed capital investment environment. This is evidenced by a decline in the number of skilled teams, who are now centred in fewer locations. Other features are an aging and retiring ‘Baby Boomer’ generation, coupled with a low uptake of new graduates and the uncertainty in predicting future capital expenditure programs and requirements. Combine this with a reluctance of cash-poor operations to modernise and adapt in an environment of low metal prices, and there is a real uncertainty in how service providers will meet industry needs as they evolve.The industry that supports operations and new projects is suffering a rapid decline in the currently severely curtailed capital investment environment. This is evidenced by a decline in the number of skilled teams, who are now centred in fewer locations. Other features are an aging and retiring ‘Baby Boomer’ generation, coupled with a low uptake of new graduates and the uncertainty in predicting future capital expenditure programs and requirements. Combine this with a reluctance of cash-poor operations to modernise and adapt in an environment of low metal prices, and there is a real uncertainty in how service providers will meet industry needs as they evolve.Trends amongst service providers will be put forward as well as developing options and alternatives. These embrace a whole gamut of agile alternatives in the areas of partnering, alliances, commercial and shared risk models and mutual innovations. These will be discussed with some case studies and suggested approaches.Particular emphasis will be upon brownfield expansions and upgrades which have emerged recently as a preferred lower capital and focused way to achieve best practical outcome at lowest cost. There are a number of specific features of such brownfields projects including the requirement for very close cooperation between the execution team, operators, maintenance and suppliers and a maximum usage of site resources and ingenuity. Often, required investment hurdle rates are high, downtime allowed is minimal and site resources usage is maximised. This requires mutual trust, good planning and high health, safety, environment and community (HSEC) standards and practice. In many ways the practices and skills needed are the exact opposite of the historical ‘big greenfields’ project with which the industry has been geared for more recently.Another developing area has been with innovative commercial models and practices. These have been as a direct result of the more challenging investment criteria being adopted and the relative hunger of service providers. It has become more common to look at these commercial/costing alternatives very early in the project cycle as an essential project tool and not just as a possible option. These commercial solutions cover such alternatives as leasing and rental, deferred payments, build–own–operate–transfer (BOOT) and build–own–operate (BOO), whole-of-mine preferred spares and maintenance terms, and aggressive performance targets with real assurance penalties. Once again this requires very close mutual dealings and trust, and sufficient time allocation compared to a conventional approach.Citation:Coleman, R, King, J and Hunter, T, 2016. Upgrades, Modernisations and Expansions... Where Will the Expertise, Capability and Skills Come from in the Future?, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 69–76 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By E. Rubenstein, V. Gangrade, K. V. Raj, M. L. Harris

Underground stone mine ventilation is characterized by large openings with low resistances. These mines primarily face three challenges: moving adequate volumes of air, controlling and directing the airflow, and planning ventilation systems that work well with production requirements. Given these challenges, this paper examines the data collected by the Mine Safety and Health Administration (MSHA) to determine the extent to which respirable crystalline silica (RCS) and diesel particulate matter (DPM) are an issue in underground stone mines. Out of 522 sampled mines, there were 108 personal samples exceeding the RCS Permissible Exposure Limit (PEL) during 2000–2020. DPM were more prevalent than RCS in these mines with 382 personal samples exceeding the DPM PEL out of the 929 mines sampled during 2002–2020. Dilution of DPM is usually the defining parameter for design of mine ventilation systems in largeopening underground stone mines. With this knowledge, focused attention can be directed to these mines so that appropriate prevention and mitigation techniques can be utilized to prevent stone miners’ exposure to RCS and DPM and subsequent respiratory diseases.

Mar 2, 2022

By Weber P, Sneyd S

The total world steel production in 1998 amounted to approximately 780 000 000 t. The share of electric steelmaking was in the range of 35 per cent and is expected to increase further to over 40 per cent of the world's production within the next ten years. As electric steelmaking is primarily based on the use of scrap and as it is progressing more and more into higher steel grades the need for low-residual metallics will become increasingly important. Consequently, the demand for scrap substitute material will increase, reflected in the world wide spate of interest for DRI (Direct Reduced Iron) and HBI (Hot Briquetted Iron). The increased significance of DRI/HBI as a substitute for steel scrap has obviously emanated also from its comparatively lower and more predictable costs per ton and definable chemistry. In 1998 already 37 million tons of DRI/HBI were globally produced.

Jan 1, 1999

This field guide is designed for use in planning pollution control and reclamation activities on small sand and gravel operations. Its purpose is to assist operators in selecting environmentally desirable pollution control and reclamation procedures based upon their particular mining situation. The guide includes information on interpreting physical and cultural factors that must be considered in planning and implementing a mining and reclamation program, achieving environmental protection objectives, and improving community/industry cooperation. Included as appendices are a summary of state laws and a list of additional readings on the subject.

Jan 1, 1981

By A. Pellegrino, F. Collin, C. Guiducci, R. Charlier

A numerical approach for modeling coupled Hydro-Mechanical fracture behavior in 2D is presented in this paper. This approach accounts for the strong dependence of the flow characteristics on fracture apertures and offers an anisotropic description of the flow propagation in the fracture. An interface finite element and a constitutive model are developed . In order to validate the applicability of the model to general geomechanic problems, 2D simulations were performed. Results show the good application of the mathematical model and the fundamental hydraulic role played by the fractures. In diesem Beitrag wird ein Stoffgesetz vorgeschlagen um hydromechanisches Kluftverhalten numerisch zu Modellieren. Dieser Vorgang nimmt die starke Abhängigkeit der Fliesseigenschaften von der Kluftöffnung mit in Anbetracht. Ein Interfaceelement und ein Stoffgesetz wurden entwickelt. Zum validieren der Anwendbarkeit dieses Modells wurden 2D Simulationen durchgeführt. Ergebnisse haben gezeigt dass das mathematische Model anwendbar ist und dass Klüfte eine fundamentale hydraulische Rolle spielen. Une approche numérique pour la modélisation du comportement couplé hydro-mécanique des fractures en 2D est présentée dans ce papier. Cette approche prend en compte la forte dépendance des caractéristiques du flux de fluide sur les ouvertures des fractures et présente une description anisotrope de la propagation du flux dans la fracture. Un élément fini d'interface et un modèle constitutif sont développés. Dans le but de valider l'applicabilité du modèle à des problèmes généraux de géomécanique, des simulations 2D ont été réalisées. Les résultats montrent la bonne application du modèle mathématique et le rôle hydraulique fondamental joué par les fractures.

Jan 1, 2003

By N. A. Eilertsen

Mining operations were in progress at the Shawangunk mine near Summitville, Sullivan County, N. Y. as early as 1843 and again as late as 1918. Difficulty in effecting mechanical separation of sphalerite and galena was the primary reason for abandonment by various operators. The Bureau of Mines investigated this mine by diamond drilling, sampling, and performing beneficiation tests. The investigation included the construction of 1.25 miles of access road and the completion of 6,526 feet of core drilling in 24 holes. In addition, 151 samples were taken in the mine. The investigation proved an extension of ore contiguous to the old mine workings and resulted in the discovery of another ore shoot at depth. The ore occurs as fissure filling in a fault zone and contains concentrations of zinc and lead sulfides with minor dissemination of chalcopyrite in a quartz gangue. Metallurgical tests indicate that the ore can be concentrated by selective flotation.

Jan 1, 1950

By K. E. Robinson

Appendix A is an abridged extract of the report prepared by the Geotechnical and Structural Engineering Society of Idaho, and presents the results of their one-year study to evaluate the feasibility of disposing mill tailings by landfill construction. Appendix B describes the field and laboratory testing program completed by RDM to assess the effectiveness of a soil (slimes) liner as a means of seepage control to reduce the introduction of contaminants into the local ground water regime. Appendix C presents a summary of a thesis by Lawrence Martin on the analysis of the acid production potential of mill tailings, and the results of geotechnical testing of mill tailings completed by ROM. Appendix D describes potential landfill sites identified within the study area, the development of these sites to meet the present needs of the mining industry and the future requirements of the community is described. Appendix E summarizes the main legislation impacting on tailings disposal. Appendix F discusses the environmental and socio-economic factors that should be considered.

Jan 1, 1981

By D. A. Barr

High-grade gold-silver mineralization associated with electrum and argentite was discovered in a quartz vein at the Chappelle property, 273 km north of Smithers, B.C., in 1969 following a regional geochemical reconnaissance program in the Cassiar-Omineca Mountains. Subsequent exploration resulted in the discovery of numerous quartz veins with associated precious-metal values in a belt 17 by 3 km in area centrally located within Toodoggone Group volcanic and sedimentary rocks of Lower to Middle Jurassic age and a window of Takla Group volcanic rocks of Upper Triassic age. More detailed investigations, consisting principally of 5677 m of surface drilling in 57 holes and crosscutting, drifting and raising on Chapelle Vein A, has outlined a high-grade gold-silver-bearing shoot with a strike length of 200 m, an average width of about 3 m and extending to an average depth of about 40 m below surface.

Jan 1, 1978

By Morris Steinberg, John Wulff, Robert Kamm

IN powder metallurgy it has often been observed that shrinkage may occur in one direction and growth in another during sintering. Even in long-time sintering experiments the rate of shrinkage may be different in different parts of the compact. In the fabrication of some parts requiring a constant permeability it is even questionable in some cases whether pressing from one direction should be attempted. These observations require for their interpretation a more detailed study of green or pressed density than has heretofore been available. Usually average density measurements of the whole compact are made and in some cases carefully cut sections are measured. A different approach to the problem was first mentioned by Rakowski1 and also used by Balshin.2 Balshin's diagram is reproduced in Fig r and schematically shows the result of pressing three layers of metal powder with fine intervening layers of graphite. The retarding effect of the die walls and a qualitative example of the density distribution is evident. More quantitative information about the distribution of density within a cold-pressed powder compact would be useful in showing the variation in density in compacts as influenced by the type of powder, shape of die, lubrication during the process, and other variables. Furthermore, information about the cracking of cold-pressed compacts may be obtained from an analysis of the stress distribution within a powder compact, and some information about the stress distribution can be obtained in turn from the density and strain distributions. A more detailed report on some of the present experiments appears in reference 3. PRESENT INVESTIGATION In order to ascertain the density gradients in cold-pressed metal powders, a deformable lead grid within the powder was employed. After pressing in cylindrical dies the ejected compact was radiographed, giving a pattern of the deformed grid. From the radiograph density and deformation from point to point is readily measured. From the radiograph strain distribution and stress trajectories were also determined. The latter also permits the determination of the coefficient of friction at the die wall. This technique indicates that the densest part of a compact pressed from one side is at the top outer circumference and the least dense region at the bottom circumference near the stationary plunger. For some heights of compacts the density at the axis is such that the lower density is at the top rather than at the bottom. So irregular a density distribution is due primarily to die-wall friction. As the ratio of diameter to height of compact is increased the die walls play a correspond¬ingly smaller role. More uniform density

Jan 1, 1947

By G. P. Holmes

"IntroductionThe copper-molybdenum property of Brenda Mines Ltd. is located 18 miles north west of Peachland in the Okanagan Valley of the Southern Central interior of British Columbia. The actual site is 50 miles north of the international boundary and 150 air miles east of Vancouver at an elevation of 5000 feet above sea level. The earliest written mention of the prospect is found in the Geological Survey of Canada, Memoir No. 243, issued in 1947 by Dr. H.M.A. Rice. In 1954 the area was staked by a prospector, Bob Bechtel, who interested Bern Brynelsen of Noranda Exploration in examining the claims. A joint Noranda - Kennecott program resulted but since the grades were so low the property was not taken up until in 1964 a re-examination by Chapman, Wood and Griswold produced recommendations leading to the construction of the Brenda Mine as it is today.The rounded, timber covered mountains of the area are composed of the tuffs, argillites and limestones of the Upper Triassic Nicola Group, which is intruded by a Jurassic quartz diorite, called the Brenda stock0 The actual orebody occurs in a strongly fractured zone within the Brenda stock, approximately 1500 feet from the contact with the Nicola group0 The ore minerals, .chalcopyrite and molybdenite, associated with pyrite and magnetite of lesser importance, occur as fillings within the fractures 0 The grade of the ore decreases outwards from a central higher grade core and in January 1971 total reserves were estimated at 165 million tons assaying 0,182% Copper and 0,049% Mo."

Jan 1, 1972

By John Wulff, Robert Kamm, Steinberg Morris

In powder metallurgy it has often been observed that shrinkage may occur in one direction and growth in another during sintering. Even in long-time sintering experiments the rate of shrinkage may be different in different parts of the compact. In the fabrication of some parts requiring a constant permeability it is even questionable in some cases whether pressing from one direction should be attempted. These observations require for their interpretation a more detailed study of green or pressed density than has heretofore been available. Usually average density measurements of the whole compact are made and in some cases carefully cut sections are measured. A different approach to the problem was first mentioned by Rakowskil and also used by Balshin.2 Balshin's diagram is reproduced in Fig I and schematically shows the result of pressing three layers of metal powder with fine intervening layers of graphite. The retarding effect of the die walls and a qualitative example of the density distribution is evident. More quantitative information about the distribution of density within a cold-pressed powder compact would be useful in showing the variation in density in as as influenced by the type of poKder, shape of die, lubricatioll during the process, and other variables. Furthermore, information about the cracking of cold-pressed compacts may be obtained from an analysis of the stress distribution within a, powder compact, and some information about the stress distribution can be obtained in turn from the derlsity and strain distributions. A more detailed report on some of the present experiments appears in reference 3. Present Investigation In order to ascertain the density gradients in cold-pressed metal powders, a deformable lead grid within the powder was employed. After pressing in cylindrical di" the ejected compact was radiographed, giving a pattern of the deformed grid. From the radiograph density and deformation from point to point is readily measured. From the radiograph strain distribution and stress trajectories were also determined. The latter also permits the determination of the coefficient of friction at the die wall. This technique indicates that the densest Part of a compact pressed from one side is at the top outer circumference and the least dense region at the bottom circumfercnce near the stationary plunger. For Some heights of compacts the density at the axis is such that the lower density is at the top rather than at the bottom. SO irregular a density distribution is due primarily to die-wall friction. As the ratio - diameter to height of compact is increased the die walls play a correspondingly smaller role. More uniform density

Jan 1, 1947

By John Wulff, Steinberg Morris, Robert Kamm

In powder metallurgy it has often been observed that shrinkage may occur in one direction and growth in another during sintering. Even in long-time sintering experiments the rate of shrinkage may be different in different parts of the compact. In the fabrication of some parts requiring a constant permeability it is even questionable in some cases whether pressing from one direction should be attempted. These observations require for their interpretation a more detailed study of green or pressed density than has heretofore been available. Usually average density measurements of the whole compact are made and in some cases carefully cut sections are measured. A different approach to the problem was first mentioned by Rakowskil and also used by Balshin.2 Balshin's diagram is reproduced in Fig I and schematically shows the result of pressing three layers of metal powder with fine intervening layers of graphite. The retarding effect of the die walls and a qualitative example of the density distribution is evident. More quantitative information about the distribution of density within a cold-pressed powder compact would be useful in showing the variation in density in as as influenced by the type of poKder, shape of die, lubricatioll during the process, and other variables. Furthermore, information about the cracking of cold-pressed compacts may be obtained from an analysis of the stress distribution within a, powder compact, and some information about the stress distribution can be obtained in turn from the derlsity and strain distributions. A more detailed report on some of the present experiments appears in reference 3. Present Investigation In order to ascertain the density gradients in cold-pressed metal powders, a deformable lead grid within the powder was employed. After pressing in cylindrical di" the ejected compact was radiographed, giving a pattern of the deformed grid. From the radiograph density and deformation from point to point is readily measured. From the radiograph strain distribution and stress trajectories were also determined. The latter also permits the determination of the coefficient of friction at the die wall. This technique indicates that the densest Part of a compact pressed from one side is at the top outer circumference and the least dense region at the bottom circumfercnce near the stationary plunger. For Some heights of compacts the density at the axis is such that the lower density is at the top rather than at the bottom. SO irregular a density distribution is due primarily to die-wall friction. As the ratio - diameter to height of compact is increased the die walls play a correspondingly smaller role. More uniform density

Jan 1, 1947

By Gary Anderson

??Privately Held Corporation ??Incorporated in Delaware, May of 2002 ??HQ in Malvern, PA (just outside Philly) ??Approx 40 employees ?9 Field Engineers ?MSHA Certified ?10 Development/NOC Engineers ?Site Survey/Site Design ?RF Engineers ??Standards Based ?IEEE 802.11 ??Commercial Off the Shelf (COTS) ?Gateworks, Ubiquity, Atheros, Linux Based ??Technology was developed and inspired by the lack of communications during the terrorist attacks of Sept. 11, 2001

May 1, 2009

By Michael A. Piepenburg

The East Side Access (ESA) Project will extend Long Island Rail Road (LIRR) into midtown Manhattan via 11 km of tunnels, a new terminal station and associated support facilities. In addition to the hard-rock tunneling currently underway in Manhattan, soft-ground tunnels in Queens will traverse beneath Amtrak?s Sunnyside Yard and Harold Interlocking, the busiest rail interlocking in North America. This paper details ESA?s coordinated approach to interfacing with both Amtrak and LIRR with regard to the planned tunnels, shafts and related construction beneath or adjacent to the operating railroads. This interface includes integration of railroad staff, extensive presentations, reviews and agreements with the railroads regarding settlement mitigation, real-time automated geo-instrumentation monitoring, ground improvement, and geotechnical/environmental controls.

By Dale C. H. Nevison

One of the most intensive of material rivalries is the confrontation between zinc die castings and plastic injection moldings. Pressed hard by the plastics industry, zinc die casters are learning how to make parts with less material yet without sacrificing quality. The key to this new trend is the technique of Thin Wall die casting. The obvious benefits of Thin Wall are lighter weight and lower cost. Again, obviously, these are the very selling points that put plastics into many appliance and automotive parts formerly made of zinc. One of the factors that has been most conducive to the outstanding growth of plastics has been the increasingly prevalent concept that "adequate" properties are sufficient, especially if there are cost advantages. Most of modern design today is oriented around the reasonable life of a product, rather than indefinitely extended life. This is simply an acknowledgment of the existence of a design environment that pervades many areas, reflecting the life-cyclic desire for change. Too often, so-called "weight-saving" materials end up being very costly - not only in production, but in durability and dependability. Change for the sake of change usually doesn't effect a change for the better. In the majority of cases, the best bet is to design in traditional materials and minimize the material needed, while maximizing the efficiency of the production process. Component prices of products to be produced from either plastics or zinc must be studied in detail to determine which material will produce the lowest cost of manufacture. It is not uncommon for two parts, similar in appearance at a casual look, to have a considerable difference in energy requirements and production costs. Detailed cost estimates of the advantages of each material should therefore be prepared for zinc and plastic parts before the final design and material selection decisions are made.

Jan 1, 1978

By F. J. Sotillo

The objective of this investigation was to determine the feasibility of using a high-pressure roll mill (HPRM) to improve the separation efficiency of dolomite from apatite in downstream operations when treating high-dolomitic pebbles. High-dolomite samples from four phosphate mines were used for the test program. The research work plan included sample characterization studies; INSTRON tests to develop preliminary crushing data; high-pressure roll mill evaluations to determine crushing parameters, such as feed rates, rolls speed and gap, and applied torque, pressure and energy; and screen, microscopy, and flotation studies to assess dolomitelapatite separation efficiency. The results of the HPRM tests show that commercial products for all four mines can be obtained. Recoveries of 74-82% of the P2O5 and rejections of 46-83% of the MgO were reported with an specific energy consumption of 0.2-0.5 of that of a laboratory rod mill.

Jan 1, 1998

By S Worden, P A. Kirsch, A Kirsch

Despite the current downturn, coal remains an important commodity in the Australian economy. Increasing coal resource development has resulted in increasing competition for land use in coal mining regions across the country with communities and other stakeholders becoming more adept at articulating their concerns regarding this competition in a range of traditional and social forms of media. In this environment, obtaining and maintaining a social licence to operate (SLO) is problematic and has been identified as the fourth greatest risk facing the international mining industry.This research presents the findings from a longitudinal study on how Australian newspapers frame the views of coal mining stakeholders across each stage of the coal mining life cycle. News stories from national, state and regional newspapers in 2000, 2006 and 2013 were analysed.Over the study period, there have been significant changes in the coal mining themes being covered by Australian newspapers, the number of stories being published, the number of newspapers covering coal mining stories, and the diversity of stakeholders being quoted. How do the dominant themes in media communication change over time? How do these changes impact mining across the life-of-mine?The research confirmed that Australian journalists use framing, priming, labels and bias to conceptualise and understand the events that they report, and that this behaviour has a profound effect on public opinion.CITATION:Worden, S, Kirsch, A and Kirsch, P A, ?2014. Moving beyond economic framing of the Australian coal industry, in Proceedings Life-of-Mine 2014 , pp 365–376 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By H. Wallin, I. G. Wallace, J. Akhavan, E. Nilsson

Over the past three years the UK together with Sweden, Norway, Finland, Italy have been taking part in a EU funded Leonardo da Vinci programme. More recently EFEE have participated in the project known as the EU15/10/200715/10/2007Excert project which is aimed at addressing the perceived loss of explosives expertise in several EU nations. This could have implications for explosives safety and industrial competitiveness. The paper outlines the work that has so far been done in phase 1 and describes the work planned for the second phase of the project. The paper will describe work in the UK to develop competencies for all explosives workers in both the civil and defence sectors. These competencies in the form of National Occupational Standards have now been approved in the UK and are accompanied by a range of 24 new National Vocational Qualifications launched in May 2006. The paper will show how the standards define knowledge and skills and how these form the basis for vocational qualifications as well as higher education awards and professional qualifications. This UK initiative is now being considered in other EU countries and the project has now been extended to also include Germany, France, Portugal, Czech Republic, Lithuania and Estonia. To support the occupational standards and qualifications work is also being carried out to improve learning provision in the explosives area. In addition to formal educational and conventional training courses a series of workplace learning initiatives are being pursued as well as internet learning packages. Examples of these initiatives will be given.

Jan 1, 2008

By H. Agnerian

"A survey of 925 mineral property transactions worldwide was carried out between 1987 and 2004. These mineral properties with reported Mineral Resources include 457 gold properties, 322 base metal properties, and five platinum group element (PGE) properties. Based on constant Canadian dollars, the results of the survey indicate that:• In general, unit metal values in the ground (e.g. $/oz Au or $/lb Cu) have kept pace with the changes in the respective metal prices during the period of the survey.• A general decrease in unit gold values in the ground has occurred from about $57/oz Au in 1987 to about $11/oz Au in 2002 for Canadian mineral properties, with the exception of a peak of $58/oz Au in 1996.• A similar trend for mineral properties has occurred in the United States, but with lower unit values, in the range from $1/oz Au to $10/oz Au during the last three years of the survey. • Unit metal values in the ground for gold properties in Canada were higher than for those in the rest of the world.• Unit metal values in the ground for copper properties in Canada were in the mid-range compared with other countries in the rest of the world; the United States and Australia were higher and Latin America, Asia, Africa, and Europe were lower than in Canada.• Unit metal values in the ground for zinc properties in Canada were also in the mid-range compared with other countries in the rest of the world; Latin America and Europe were higher and the United States, Australia, and Asia were lower than in Canada.• Unit metal values for nickel properties in Canada were highest compared with other countries in the rest of the world, followed by the United States, Australia, Africa, and Asia.• Gold values in the ground in Canada have ranged from 6% to 14% (with an average of approximately 10%) of the gold price.• The unit values of base metals in the ground have been in the order of 2% of the quoted metal price, during the period of the survey."

Jan 1, 2006