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By H. Douglas Dahl

Thank you, Don Gentry, for your generous introduction. It is not adequate simply to say that I appreciate very much the vote of the Award Committee putting forth my name as the winner of the 1992 Daniel C. Jackling Award. To look at the list of previous Jackling Award winners is a humbling experience. The Society for Mining, Metallurgy, and Exploration has been blessed with some exceptional members over the years, and I feel privileged indeed to be included among the Jackling Award winners. During the years of my education at Penn State, my field of specialization was mining engineering, with particular emphasis in my master's and Ph.D. work on rock mechanics. But my career has not been quite so tightly focused as that. I have been involved with coal mining in all its variety - its technical aspects, both theory and practice; and its business side, dealing with management and labor, accountants and lawyers, politicians and environmentalists. And I have also been involved with related fields - construction; exploration; barges, railroads, ships and docks; supply houses; the coke business; you name it. Coming from that practical background, I believe it is most appropriate that I talk with you today about some practical matters. But I will not advise you today how to mine coal or protect roof in a hard-rock mine. You fellows know how to do that. The practical matters that I have in mind relate to policy - national policy. I will acknowledge immediately that national policy is often much less than practical, but bear with me as we explore the subject together. I am reminded of a supervisor I had early in my career. He very strongly advised me, back in 1961, to "get involved in the political process," for without objectivity injected into our national policy making, we will become a second-rate economic power. I have selected as the subject of my remarks today, "Coal and the de facto National Energy Policy." There is an energy policy relating to coal, a de facto one, and it's the one we see as a result of regulation, attitudes and culture from our nation's capital. This de facto policy is the one we in the coal business live with every business day. My thesis is very simple - Coal is, in fact, a vital part of our national energy policy and will remain so, as a practical matter, no matter what politicians may do to us, or not do to us. Coal will prevail - that will be the happy ending to my story in which, of course, we are the good guys in the black hard hats. But first, I must flesh out the plot with some other characters and with some threatening activities. There are five main characters in my story: in order of appearance - Perpetual Politics, Rampant Regulation, Selective Science, Electrification and Confident Coal. The time: the present. Perpetual Politics is always a threat to coal. When you cross the Capital Beltway into Washington, D.C., check your wallet and your gold fillings, because you're not likely to run into any friends. On Feb. 20, 1991, just over one year ago, President Bush presented to Congress his National Energy Strategy. It's a thick document of more than 260 pages, with discussions on securing our future energy supplies, increasing energy effi-

Jan 1, 1993

By Stanley R. Riggs

The rocks exposed in the phosphate district are of Neogene age and consist of clayey quartz and phosphorite sands overlying phosphatic dolomite. The Bone Valley Formation is redefined as a marine phosphorite containing primary phosphorite and abundant terrigenous sediments. It contains a Middle Miocene vertebrate and invertebrate fauna and conformably overlies the Hawthorn Formation containing similar invertebrate fauna. A new, unnamed formation, with Pliocene and Pleistocene fauna and containing reworked phosphorite, overlies the Bone Valley disconformably. Its phosphorite is derived from the subjacent Bone Valley by post-Middle Miocene erosion and deposition in stream channels and marginal marine environments. The Bone Valley contains two main types of primary marine phosphorite. Orthocbemical phosphorite, a direct precipitate of microcrystalline phosphorite (microsphorite), occurs as a cement or binder in thin beds. Allochemical phosphorite consists of clastic phosphorite particles that were originally formed as microsphorite on another part of the shelf. Microsphorite was deposited in a very shallow open marine environment which had an abnormally high phosphorous content caused by upwelling currents. The mechanism of deposition is still in doubt, but organisms probably were a major factor. Soon after deposition, microsphorite was indurated, periodically torn up, and the resulting fragments transported and deposited elsewhere on the shelf. These processes account for a great portion of the clastic phosphorite in the Miocene deposits of Florida. The primary fossil skeletal material is of minor importance.

Jan 1, 1965

By P. J. G. du Toi

Anaconda's experience with percussion longhole drilling in Butte, Montana, has consisted of six phases: 1. Drilling horizontal blast holes in stopes with push feeds. 2. Ring and parallel blast hole drilling in longhole stopes with bar mounted as well as skid jumbo mounted longhole drifters. 3. Ring and parallel drilling in raise climber shrinkage stoping using special raise climber drilling decks designed and built in Butte, Montana. 4. Parallel longhole drilling in horizontal cut and fill stopes with monorail jumbo. 5. Drilling water drain holes between mine levels. 6. Drilling leach holes through caved zones into old stope workings for leaching purposes. 7. Sample hole drilling.

Jan 1, 1970

By John Newby, Ulf Gwildis, Fred Marquis

From the Brightwater Conveyance System in Seattle to the Second Narrows Water Supply Tunnel in Vancouver, BC, the design and construction of deep-lying tunnels in the Pacific Northwest often require the incorporation of deep portal shafts. Alluvium overlying marine and glacial deposits combined with the high regional seismicity is the common geologic setting. The latest example illustrating the development of shaft design for this scenario is the 40-m-deep shafts of the Annacis Island Wastewater Treatment Plant New Outfall System. The main components of the shafts include the initial lining, providing the excavation support system to be used for launching and receiving a 5-m-diameter TBM; and the final lining, designed to withstand all static and seismic loads and to remain viable for the intended design life. This paper presents design and construction considerations for these shafts against the background of and lessons learned from past project experiences.

Jun 13, 2021

By James W. Baxter

State geological surveys promote sound procedures for evaluation of mineral resources before development-procedures that protect the environment and accrue maximum benefit to citizens. Sophisticated laboratories have been equipped for geophysical, geochemical, petrographic, and mineralogic characterization of materials to assist citizens in land-use planning and optimum development of natural resources, activities clearly within purview of the state. Proper use of these facilities in support of exploration in a competitive, free-enterprise system should be based on achieving ultimate benefits to the public, but, in general, should not entail competition with commercial laboratories.

Jan 1, 1982

By David G. Van Hersett

The single most unique design feature of the Centralia Coal Mine is the public information program. Just what the heck does public information have to do with the development of a coal mine? The utilities of today have had to build larger and larger plants to keep down the costs of power to the consumer. The large plants require huge amounts of capital, take up large areas of real estate, consume unprecedented amounts of coal, and generate large quantities of waste products which have to be reckoned with. Coal mines supplying these plants have also increased in size and production to meet the power plants' unending appetite for coal. This means the disturbance of great areas of land and significant alterations to the landscape. Today's public is greatly concerned about the environment in which he is living. The great size of a power plant with its large stacks, coal piles, and the coal mine with its large earth movers, disturbed acreages and the resulting waste products of both operations appears to present a threat to his environment. Because of this,' many power plants and coal mines are having public acceptance problems. This has resulted in the passage of stringent legislation and in some cases brought upon construction delays for major power plants.

Jan 1, 1970

By C. B. Manula

Languages such as SIMSCRIPT and GASP have reduced the programming skills required to build simulation models, but not to a level where these can be used by a busy engineer or manager unless he has extensive programming experience. In an attempt to make simulation a more readily available tool, Sanford (1969) structured a generalized materials handling model (UGMHS)* for underground coal mining. The majority of materials handling systems consist of a set of moves and a set of pieces of equipment required to execute the moves. UGMHS gives a technique for describing and classifying the elements in these sets and then a technique for simulating the interactions of these elements as the materials handling system operates. To apply the model, the user simply furnishes data parameters and a fixed set of orders to the computer for his own problem. This new philosophy of dynamic simulation as applied by UGMHS was demonstrated in the paper by Sanford and Manula (1973). A dynamic model of underground coal mining was presented for the purposes of systems design and selection of equipment for a completely new operation and the analysis of existing ones for possible alterations, additions, and general improvements. The main differences between this application and its predecessors is the ability to transport material from multiple mine faces to multiple mine destinations and the ready adaptability to a wide variety of mine layouts. The second difference that characterizes the model is the deterministic simulation of equipment moves according to their mechanical capabilities and the physical profile of the mining scheme. Here, the computer generates performance data in the absence of time studies to compare equipment rather than operator performance.

Jan 1, 1974

By A. J. S. Spearing, T. Kostecki, D. Benton

The use of paste backfill in room-and-pillar coal mines in the United States needs to be fully investigated. This paper discusses a series of physical tests that were conducted to examine the support benefits of theoretical paste backfill regimens in Illinois Basin room-and-pillar coal mines, which necessarily included consideration of weak floor conditions. The series of tests included those simulating strong floor conditions, weak floor conditions, under-confined scenarios, and testing of actual coal-based paste backfill samples. The testing indicated that a paste backfill regimen utilizing a minimum backfill strength of 22 psi at a minimum fill height of 50% of pillar height could significantly increase the longterm stability of coal pillars in the Illinois Basin. Considering typical coal wash plant recoveries, 50% fill would be feasible.

Jan 1, 2014

By Isabel F. Barton, Matthew J. Gabriel, CARSON ROBERTS, JOHN LYONS-BARAL, LEON DUPLESSIS, Mark D. Barton

Geometallurgical characterization is increasingly used in the mining industry to model ore types, predict process performance and identify potential recovery issues ahead of time. However, most geometallurgical assessments are based on bench- or laboratory-scale analyses of relatively sparse samples, leaving most of the orebody characteristics known only by inference until the rocks are actually mined. In this pilot study, we test drone- and tripod-based hyperspectral imaging for mapping mineralogy across mine highwalls, dumps and leach pads. The results show that hyperspectral imaging can successfully map the types and distribution patterns of key minerals (especially carbonates, sulfates, clays, other phyllosilicates) and other important features (such as lixiviant ponding on leach pads), bringing geometallurgy into the field to provide crucial inputs to process decisions.

By Wayne S. Cavender

The geochemical association of arsenic and gold in epithermal precious metal deposits of the Basin and Range province is well documented, and in this paper I wish to discuss the evaluation and utilization of this element association for geochemical gold exploration. In 1961-62, I conducted an exploration program on lands controlled by Getchell Mine, Inc, and centered about the Getchell gold mine itself, Besides exploring for new gold deposits, the program was to evaluate these lands for potential deposits of any type; thus, a multi-phase program encompassing a number of exploration methods was conducted. I shall not elaborate on the process of designing the program or of integrating the various methods, but for gold exploration, geochemical methods were determined to have the best potential. This paper is based on that effort. Figure 1 shows the exploration area, which covers the northern half of the Osgood Mountains in eastern Humboldt County, Nevada. The Getchell $line is on the east flank of the range and is about 40 miles northeast of Winnemucca.

Jan 1, 1964

By Alphonse C. Van Besien

It is doubtful if anyone knows precisely how many U.S. coal miners have been killed by roof falls. In 1931, 51 miners were killed by falls or rock in every 10-day period (Paul, 1). Roley (2) indicated that from 1882 to 1945, over 3,700 men were killed by roof falls in Illinois alone. During this 63-year period, roof falls accounted for 47.6 percent of the coal mine accident fatalities. Similarly, Price and Nolting (3) reported that during the 10-year period beginning in 1937, roof falls claimed over 50 percent of the lives lost in West Virginia coal mines. Over 150 miners died under fallen rock in West Virginia alone, in each of those years. Certainly, the statistics have improved over the years. The Theodore Barry Report of 1971 (4) indicated that during, the previous 4 years, fewer than 100 miners per year lost their lives to roof falls--in the entire United States. The improvement is less remarkable when it is realized that the accident rate has declined only as the number of miners employed underground has declined. The TRW Report (4) pointed out that although the number of fatalities in underground coal mining (from all causes) had been cut in half from 1956 to 1965, the fatality rate per thousand miners had remained virtually constant. The decreased accident rate was due not to a reduction in hazards but to a reduction in work force. Roof falls still claim approximately 50 percent of the lives lost in underground coal mines. Considering the increased underground production of coal which must result from our energy crisis, the environmentalists' pressure against strip mining, and our inevitably diminishing supply of strippable coal, it is apparent that some means must be found to reduce the number of lives claimed by coal mine roof falls.

Jan 1, 1973

By David E. Sims

Asarco has been using computer-aided open-pit mine design since 1966. The in-house developed program package includes drill-hole analysis programs, interpolation routines, and three-dimensional open-pit design programs. The financial analysis step after pit design required that a reasonably accurate schedule be produced so that a good cash flow model could assess the feasibility of a project. The manual method of scheduling was too time-consuming for feasibility work, so a computerized scheduler was required. Since no computerized mine scheduling programs existed, we requested proposals from consulting firms to develop such a program. The selection of a consulting firm, the formulation of the contract and design specifications required about three years to accomplish. The consulting firm, Systems Control Inc. (SCI), of Palo Alto, spent over one year doing the programming and testing alone. The details of the program development were reported in "Computerized Year-by-Year Open-Pit Mine Scheduling," SME-AIME Transactions, December 1974. In June of 1973 the program, which SCI dubbed Optimum Resource Extraction or ORE, was installed. Version 1 of ORE was utilized successfully on three separate properties over a period of two years. During this time it became obvious that some of the original design specifications were restrictive, and certain modifications were required. The ORE program was submitted for modification, and after one year version 2 was operational in May of 1976. The program now consists of approximately 20,000 lines of FORTRAN source statements grouped into 190 subprograms, and runs in a 450K region of Asarco's 370/148 in Cranford, NJ. The Tucson com¬puter (370/115) is tied to the Cranford computer via a 9600 baud leased T.P. line, for running mine scheduling and other large mine planning programs.

Jan 1, 1979

By J. A. Delgadillo, C. A. Pérez-Alonso

"Tumbling mills using balls as grinding media are used extensively in the mining and cement industries to produce fine powders; however, it is well known that the process of size reduction is highly energy-intensive. For this reason, much of today’s comminution research is aimed at understanding grinding mechanisms, by estimating power draft and modeling milling circuits using the discrete element method (DEM). DEM predicts individual particle trajectories, the distribution of energy and contact forces at each collision, lifter wear and power draw. This paper presents a prediction of the discharge particle size distribution using three components, mass balance model (sometimes referred to as a population balance model, PBM), impact energy distribution of the mill obtained from the simulation of the charge motion using DEM and breakage characteristics of particles determined from drop-ball tests. DEM simulation of the charge of a tumbling mill was done using the code MinProSim 1.0 to obtain impact spectra at different operative conditions. Then, the population balance model (PBM), based on impact energy distribution, was used to predict the final particle size distribution in a batch mill and compared with experimental data. It is demonstrated that the DEM-PBM approach allows a reliable solution to predict particle size distribution for tumbling mills. Ideally, the model has to predict size distribution for any operational condition and feed characteristic; however, it has been shown that predictions include some degree of error.IntroductionThe discrete element method (DEM) has recently become a powerful numerical tool that can be used to investigate internal mill charge in ball mills. The early work of Cundall and Strack (1979) used DEM to analyze soil as a discrete medium. Later, the method was improved to simulate the operation of tumbling mills and optimize the design in order to increase the efficiency of energy utilization. Also, it is of great interest to relate ore breakage based on impact energy spectra obtained by DEM simulations and the breakage distribution function used in the PBM to predict particle size distribution in tumbling mills.King and Borgeous (1993) broke single particles in an ultra fast impact load cell to compute the phenomenological parameters in a microscopically more detailed population balance model. Kapur et al. (1997) simulated the size spectra of progeny particles produced by impact grinding as a function of the impact energy. Narayanan (1987), Narayanan and Whiten (1988) and Lira and Kavetsky (1990) estimated the energy-dependent breakage distribution function for scaleup and modeling of industrial ball mills."

Jan 1, 2015

The 32nd annual American Hall of Fame Awards Banquet and Fundraiser, sponsored by the Mining Foundation of the Southwest (MFSW), will be held at the JW Marriott Tucson Starr Pass Resort & Spa on Saturday, Dec. 6, 2014. Each year, one living Hall of Fame inductee, up to three Medal of Merit recipients, honorees from mining?s past, and recipients of an Industry Partnership Award and a Special Citation are recognized for their respective contributions to the mining industry. Armine Frederick Ban?eld Jr., past chairman and founder of Mintec, Inc. located in Tucson, AZ, will be honored as the 2014 Hall of Fame Inductee at the awards banquet. Banfield founded Mintec from his Tucson apartment in 1970 and expanded it to a global operation. Under his guidance, Mintec won the 2013 President?s E-Award for Exports ? the highest recognition any United States company may receive for making a significant contribution to the expansion of U.S. exports. Medals of Merit will be awarded to Corale L. and James A. Brierley, founder and principal of Brierley Consultancy LLC; David Nicholas of Call and Nicholas Inc. and Scott M. Shields of Joy Global. The Brierleys are being recognized for their true scientific partnership with parallel achievements in academia and in business development. Nicholas is being recognized as the co-founder of Call & Nicholas and for his noted expertise in mining geotechnical engineering. Shields is being recognized for his innovative work with GPS integration and for playing a key role in laying the foundation for autonomous mines of the future. As representatives of mining heritage, the Hall of Fame will induct Patrick E. Connor, ?Father of Utah Mining,? for pioneering mineral exploration efforts in Utah; Earl Tappan Stannard, president of Kennecott Copper Co., for transforming Kennecott in to one of the largest U.S. copper producers; Arthur Barrette Parsons, mining editor and author, for his book ?The Porphyry Coppers in 1933,? a seminal work detailing the history and technical information regarding major porphyry copper deposits and Ernest R. Dickie, general manager of Bagdad Copper Co., for his foresight in converting the mine from block caving to open pit. The Industry Partnership Award will be presented to Empire Southwest, a third generation family owned dealership for Caterpillar which consistently ranks among the top Caterpillar dealers worldwide. A Special Citation will be presented to employees of Rio-Tinto-Kennecott Bingham Canyon Mine for their speedy recovery from the massive Manefay slope failure in 2013.Early sponsors include Ames Construction, Asarco LLC; Brierley Consultancy LLC; Caterpillar Inc.; Click Automotive Team; Deconcini McDonald Yetwin & Lacy, P.C.; Empire Southwest; Florence Copper Inc.; Freeport-McMoRan Copper & Gold Inc; Independent Mining Consultants Inc.; Joy Global Inc.; Komatsu America Corp.; Liebherr Mining Equipment; Lowell Copper Ltd.; M3 Engineering & Technology; Modular Mining Systems Inc.; MWH Global; Newmont Mining Corp.; Ram Enterprise; Rio Tinto/Kennecott, Sonoran Process Equipment Co.; Southwest Energy LLC and SRK Consulting. MFSW is a nonprofit organization and its mission to promote the value of the industry to our community and profession to ensure its future success. Funds raised from its annual banquet are principally designated to support the foundation?s education program, a partnership with the Lowell Institute for Mineral Research at the University of Arizona.

By Lyle A. Hale

The subject area known as upper Dry Valley is located 15 miles due east of Soda Springs in Sections 14 and 23, Township 9 South, Range 44 East, Caribou County, Idaho. The railroad extending from Soda Springs to its terminus at El Paso's Maybe Canyon mine is 8z miles to the north in lower Dry Valley. Initial data derived from trench work in 1962 revealed a variety of econom¬ically significant alterations of the phosphatic beds related to the rather unique geomorphic development in the northern part of phosphate lease 1-012989. It was apparent that such conditions, while valid for near-surface beds in a strike direction, would be misleading if projected to the proposed depth limits of strip mining. Consequently, a subsurface mapping program was initiated in 1963 to determine: (1) the depth and horizontal extent of weathering and related phe¬nomena, (2) the depth, thickness, and quality of ore beds and intervening strata, and (3) structural geology as a guide for mining procedures. Successful use of a scintillometer in 1956 to detect the subcrop position of phosphate beds in the Smokey Canyon area of southeastern Idaho led to the conclusion that gamma radiation surveys of drill holes could be a useful aid in subsurface mapping. The objectives of this paper are: (1) briefly to describe geologic features characteristic of the phosphate lease area and (2) to demonstrate the practical application and theory behind gamma radiation logging as an effective tool in the economic evaluation of a phosphate lease.

Jan 1, 1969

By Jerry M. Whiting

Greater awareness of the increasing need to develop supplementary energy sources is accelerating us towards many basic decisions regarding future utilization of mined energy materials -- uranium, coal, oil sands and oil shale. The latter material comprises a major potential source of oil which will require creation of unusually large and low-cost underground mining systems. In this paper, the author briefly outlines and analyzes several of the factors which continue to provide the somewhat unique character of oil shale nine planning and mine operation.

Jan 1, 1974

By James M. Stauffer

There are many types of filters designed to separate a solid from a liquid, including plate and frame presses, pressure leaf filters, gravity filters and vacuum filters. This discussion will be limited to continuous vacuum filtration and, specifically, to continuous rotary vacuum disc filters, drum filters and horizontal belt filters. The use of vacuum filtration can be advantageous in that: 1. The feed slurry can be delivered to the filter either by gravity or by a simple, inexpensive low pressure pump that only has to overcome the resistance of the feed piping system. 2. The filter equipment does not have to withstand high pressures. Consequently, a wide range of materials of construction, including plastic and fiberglas reinforced polyester (FRP), can be used in the fabrication. 3. After the form time, the filter cake is exposed to the atmosphere and the cake is accessible for further operations such as mechanical or physical dewatering, washing, and sampling on a continuous basis. 4. The discharge of the dewatered solids is continuous for directly feeding to the next operation; for example, a dryer. 5. Various methods of discharge can be fitted to the filter to effect optimum discharge of the dewatered cake solids. The principal of operation of a vacuum filter, regardless of type, is basically the same. The filter incorporates a filter medium supported on a drainage system and arranged so that the mixture to be separated (feed slurry) can be introduced to one side of the filter medium on which the solids are trapped and through which the liquid (filtrate) flows due to the applied vacuum.

Jan 1, 1979

By Robert F. Kehrman

As part of the Bureau of Mines research on the In-Situ Uranium Leaching, various geophysical resistivity measuring techniques were -evaluated to identify a rapid reliable method for detecting the underground migration of lixiviant outside of the planned limits. Surface and downhole galvanic resistivity and controlled source audio-magnetotelluric (AMT) methods were tested at an in-situ uranium mine in Northern Wyoming during start-up of a new mining area. Downhole galvanic and AMT were the most promising techniques.

Jan 1, 1980

By LUKAS FAHLE, JURGEN F. BRUNE, ANDREW J. PETRUSKA, ELIZABETH A. HOLLEY, Gabriel Walton

Adverse ground behavior events, such as convergence and ground falls, pose critical risks to underground mine safety and productivity. Today, monitoring of such failures is primarily conducted using legacy techniques with low spatial and temporal resolution while exposing workers to hazardous environments. This study assesses the potential of novel simultaneous localization and mapping (SLAM)-based light detection and ranging (lidar) data quality for rapid, digital and, eventually, autonomous minewide underground geotechnical monitoring. We derive a comprehensive suite of quality metrics based on tests in two underground mines for two state-of-the-art mobile laser scanning (MLS) systems. Our results provide evidence that SLAM-based MLS systems provide data of the quality required to detect geotechnically relevant changes while being significantly more efficient for large mine layouts when compared to traditional static systems. Additionally, we show that SLAM-specific processing can achieve an order of magnitude better relative accuracy relevant for change detection than quality metrics derived from traditionally deployed tests would suggest, while reducing SLAM-drift error by up to 90 percent. In collaboration with an operating block-caving mine, we confirm these capabilities in field tests on a minewide scale and, for the first time, demonstrate methods of rockfall detection using MLS data. While more work is required to investigate optimal collection, processing and utilization of MLS data, we demonstrate its potential to become an effective and widely applicable data source for rapid, accurate and comprehensive geotechnical inspections.

Jan 1, 2023

By Donald T. Mylar

It is axiomatic that in designing a bulk material handling system the primary consideration is the functioning of the machines. The structure is secondary -its reasons for being are to support, enclose and provide access to the machine, for servicing. This results in a wide variety of supporting structures. Other considerations are: plant layout, local soil conditions, climate, local laws and codes, and last, but by no means least, the Customer's wishes.

Jan 1, 1971