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By Winthrop P. Haynes

The symposium on production for the year 1943 contains few papers on the foreign situation. It has always been the policy of officers in charge of the symposium to refrain from publishing information that might possibly injure national or private interests. At the close of the war we hope again to publish full and accurate records of production abroad. A noteworthy feature of the reports on Texas this year is the map on page 469, which shows the districts covered by the statistics. Excerpts from Circular to Authors In order to facilitate interpretation of the data in this chapter, we print the following excerpts from the Circular to Authors. The field is the unit in this tabulation. In cases of fields extending across State boundaries, such as Rodessa, it is suggested that each State author treat the section of the field in his State as a unit, and by a footnote indicate that the field extends into an adjacent State. Each place in the table may represent one of three possibilities; either the proper entry is determinable and can be supplied by the author, or an approximate figure can be supplied which is the author's best guess and should be entered followed by an x, or it does not apply to the particular field and the space is left blank. Contributions of great value may be made by the author in many cases where entries are not subject to precise determina-tion. In such cases the author should use his good judgment and make the best entry possible under the circumstances. The entry of a zero is a positive declaration, and it is an important declaration where it is in order. It is thought that the nearest whole numbers are suficiently accurate for our purposes except as to percentage of sulphur in oil. If an author desires to report any other figures to tenths, he may do so. The quantity of gas produced should include, where possible, gas sold or otherwise marketed, and gas blown into the air, burned as flares or otherwise wasted. Segregation of these figures would be interesting if the authors can make such segregation. In any event, the figures should represent as nearly as possible the total quantity of gas removed from the reservoir. Under the columns on ''Depth," the average depth to the top of the productive zones and to the bottom of the productive wells, when subtracted, should give the approximate thickness of the productive zone. For fields where this is not true because of unusually high dip or for some other reasons, it is suggested that the authors indicate in their text the approximate average thickness of the productive zone. The net thickness of the producing formation should be the thickness of the producing zone, less the estimated amount to cover the portions of the zone that do not yield oil, such as dense shales, etc. It is recognized that for some fields the authors can only make rough guesses; in such cases, they should enter their best estimate followed by an x. Average production per acre-foot need not be reported as it can be calculated by those interested from the figures given. In classifying wells as to producing methods, enter all wells that are not "flowing" in the column headed "Artificial Lift." If possible, add footnotes to indicate whether the lift is "pumping," "gas lift" or "air lift."

Jan 1, 1944

By Sina Mostaghel, M. Guo, E. Klaffenbach

The current paper is focused on evaluating the behavior of copper in a copper production slag and the assessment of metal recovery possibilities. For this reason, thermodynamic calculations were carried out to determine the influence of parameters such as slag composition, temperature and oxygen partial pressure on recovery of non-ferrous elements. It was found that the formation of a solid face centered cubic (fcc) phase, mainly consisting of iron, limits the extent of reduction that can be achieved for an industrial process. However, it could be discovered that solubility of iron in the Cu-rich liquid alloy strongly depends on presence of other elements, particularly arsenic. As part of the results of this study, the solubility of Cu in the slag at onset of fcc phase formation is presented as function of temperature, oxygen partial pressure and concentration of MgO and CaO. It was concluded that lower temperature (1200°C) and higher CaO addition (16 mass-% in this study), would result in the highest achievable copper recovery from slag. INTRODUCTION Copper slag is produced as a by-product of the copper production process. The slag is still containing a high amount of copper and other valuable metals. This demands further treatment of the slag as a secondary source of metals. In addition, the physical/mechanical properties of slag allow its use in several applications such as hydraulic engineering, civil engineering, as an abrasive and many more. These applications help reducing the use of natural resources like rock and sand. By decreasing the content of heavy metals such as Cu, Pb, Zn and As in the slag, its application in abovementioned fields becomes more attractive as the probability of releasing these elements to the environment is further reduced. To develop a pyrometallurgical slag reduction process, it is necessary to understand what describes the end point of the reduction. This point is expected at maximum copper recovery without facing operational challenges. Existing literature provide some information on the effect of different parameters such as temperature or concentration of different slag formers, on solubility of copper and heavy metals in different phases. However, due to complexity of industrial slags, equilibrium experiments and accurate thermodynamic modelling are essential to be able to reliably predict the behavior of different elements in the system and determine the end-point of reduction.

Jan 1, 2019

By L. A. Weakly

The requirement for large diesel equipment to be certified for operation in potential gassy mine conditions in western oil shale mines motivated a design engineering project to develop a dry exhaust conditioner system to replace traditional wet scrubber technology. A dry exhaust conditioner for a 600 hp diesel engine was designed and fabricated for retrofitting into a 600 hp underground haul truck. The engine conditioner package was taken through a simulated certification process at the Mine Safety and Health Administration (MSHA) Approval and Certification Center to refine test procedures and to uncover any flaws in the dry exhaust conditioner technology. The engine/exhaust system was then installed in an underground haul truck to demonstrate mine-worthiness of the system. No inherent features were discovered that would prevent the system from meeting test requirements. However, the tests did point out several deficiencies in the prototype design.

Jan 1, 1989

By William R. Nash

Introduction As ore grades decline and deposit depths increase, problems and costs of mining construction increase rapidly. Ground water greatly impacts the cost of mining construction. In developing or exploiting ore bodies or coal mines, stored ground water in waterbearing formations is often encountered. Man-made conduits or shafts are constructed, as are raise bores for ventilation (up to 6-m-diam or 20-ft-diam), or smaller diameter drill holes, used for either power cables or rock dust. In underground construction and mining, it is possible to inherit unmapped and abandoned drill holes either from oil or gas exploration, or from previous geological investigations. There also exists within underground work exposure to faults, fissures, and jointing. A mine development may encounter unknown aquifers or, unluckily, have an ore body that is an aquifer. Water may invade an existing underground structure, due to concrete deterioration or to damage that may occur to an existing shaft or tunnel concrete lining. An underground development may intersect a drill hole that was not properly grouted when abandoned. It subsequently formed a conduit or an active path to conduct water into the mine. Water inflow may range from insignificant to a magnitude sufficient to inundate an area or an entire underground development. Corrosion imposes major costs. In shafts, it can cause accelerated wear and deterioration, and subsequent early replacement of hoisting ropes. It can also cause deterioration, misalignment, and subsequent accelerated wear and replacement of timber and steel guides and buntons. Utility maintenance (power cables, air, water, and ventilation lines) also can become a problem. Corrosion imposes major costs. Skips and skiploaders provide a never-ending series of maintenance headaches when exposed to an ingress of water. Numerous problems are found in declines with invert and rail maintenance and with partitions in over-under coal mine slopes. Ground water interacting with an underground ventilation system can result in: • Increased ventilation resistance due to roof falls and the spalling of ribs caused by ice heaving. • Restriction in shaft or slope cross-sectional area due to ice buildup during winter months. This may be a safety hazard to access as well. • An increase in the moisture content entering the ventilation air that condenses underground and causes electrical and equipment maintenance problems. Underground structures also incur water-caused problems. The concrete lining in shafts, slopes, and tunnels may be subject to: • Active mine waters causing concrete and reinforcing steel to deteriorate - perhaps to the point of collapse. • Load redistribution around a concrete lining, caused by soil dislocation due to water movement. The resulting stress may be in excess of the calculated design loading. Backwall injection with grout of the completed concrete lining may solve these water inflow problems through low-pressure injections of cement and chemicals. This fills voids at the interface of the concrete lining with either the soil or rock excavation. Surface structures may be jeopardized by lowering the ground water table, resulting in surface settlements. Surface settlements can occur in buildings, headframes, hoist foundations, mills, conveyor structures, or in rail haulage. Areas of differential settlement can lead to derailments, improper wear of hoisting ropes on sheaves in headframes, and the misalignment of bearings and brakes. Mud jacking and compaction grouting may remedy these problems. To reduce operating costs, increase efficiency, and increase safety, inflow water to the mine should be minimized. For an operating mine with a water problem, a water inflow survey should be taken. Quantities of water flow should be examined at all accesses (shafts, slopes, bore holes, and raise bores) at the faces, haulages (rails or conveyors), and sump discharge. From this examination and quantity survey before and after heavy rainfalls, valuable data for elim-

Jan 3, 1984

By Henry J. Sandri

ACQUISITION JUSTIFICATION There are many reasons why companies consider acquisitions as a means to expand their operations. Some wish to reduce the impact of business cycles on their businesses. Others seek firms within the same industry for expansion and increased market share. Still others diversify in order to avoid takeovers. Whatever the reasons or justification, an evaluation of an acquisition candidate should be systematic and thorough. To many financial managers the concept of a systematic acquisition evaluation indicates the need for a regular set of evaluation criteria. While these are available from numerous sources, one basic parameter frequently overlooked is the application of these criteria to an industry which is different from the acquirer. This becomes particularly important when evaluating firms within the mineral industry. The mineral industry is significantly different from other industries to require different valuing techniques. • This paper will present a number of reasons why an acquisition candidate in the mineral industry should be evaluated differently from other acquisitions, including by other mineral firms. Additionally, this paper will review the most appropriate means of valuing a mineral firm. • Firms considering the acquisition of a mineral firm should understand the nature of the industry before ever making a tender offer. Some of the general considerations include the following: • Level of Capital Intensity: In the mid-1980's the start up cost for a gold mine has been between 20-200 million dollars and 500-1,500 million dollars for a bauxite operation. • Global Nature of Competition: Except for certain industrial minerals, most minerals and metals are traded worldwide and many on national exchanges, such as COMEX. • Start-Up Time: Many mining operations in developed and developing countries have long lead times, 7 to 10 years in some cases, prior to the start-up of production. • Long Term Nature of Investment: For most mineral operations payback usually occurs at least 7 years after production has started. Additionally, many mining operations will continue producing for 80-100 years. • High Level of Risk: The number of factors that a mining firm cannot control such as grade, volume, world supply and demand, plus the long payback periods tend to classify mineral firms at a higher than average risk compared to other investments. • Cyclical Nature: The mineral industry is cyclical in nature, experiencing long troughs and explosive peaks, thus making timing a critical issue. • Labor Intensive: Even with the large capital requirements needed to operate a mine, most mines are labor intensive in proportion to their capital equipment. • Location: Obviously, the nature of this industry requires operators to work in difficult locations, frequently far from civilized localities, in poor weather conditions and without proper supply and distribution infrastructure. One of the most important considerations is an understanding of asset replacement and asset value. Unlike manufacturing concerns, firms in the mineral industry are working toward the elimination, through depletion, of their asset base. Product flexibility is not available to a mining operation. A mineral firm basically has two options as its resource base is depleted: 1) replace the asset with new production, or 2) deplete the asset and close down operation, as in the South African gold mining model referred to later in this paper. An understanding of the

Jan 1, 1985

By Homer N. Mead

This report develops equations for decline curve analysis based upon the premise that the rate of change of the reciprocal of decline for succeeding time intervals is constant when the reservoir is produced under a fixed set of conditions. A method is shown for predicting maximum production rate against cumulative production for any reservoir. A method is also presented for predicting future production rate by an analysis of past production performance after decline has been esrahlished. INTRODUCTION No significant contribution to the analysis of decline curves by the loss-ratio method has been made since J. J. Arps paper1. The concept of loss-ratio that was developed by Arps and his contemporaries has been redefined in another way and the concept of instantaneous loss-ratio at time zero has been added. In the mathematical developmerit by Arps, production rate was related as a continuous function with time and his equatlons were developed on that basis. In this paper, production is considered to be a series of segments for equal time intervals and equations have been developed based upon these finite differences. It is realized that decline curve analysis is not the answer to all predictions of reservoir behavior. However, as production must decline from an initial maximum rate to zero in any reservoir, if such decline can be expressed as an infinite series, this series should accurately predict production. Decline curve analysis should be considered a valuable tool that may be used in conjunction with predictions of future recoveries by other methods. Various uses of the decline curve method will be discussed in this paper. Equations predicting production rate at any time and cumulative production by exponential and hyperbolic decline will be developed. Characteristic values of b related to various types of drive will be discussed. After that a hypothetical reservoir will be studied and ultimate recovery by natural depletion and pressure maintenance compared, then actual field examples will be shown and discussed. The rate-cumulative curve introduced by H. N. Marshs in 1928 is an important one for use in estimating future production rate and ultimate recovery. This graphical method is the one that is used in conjunction with the equations to be developed for predicting production behavior. EXPONENTIAL DECLINE In exponential decline each succeeding production rate per unit of time is a constant percentage of the production rate just before it. Since (1 — r) is the common ratio, where r is the constant decline rate, this condition may be expressed as a geometrical progression; thus Pn = P (1 - r)n-1 . ......(1) Where r is less than unity, r Since P1 (1 - r)n = Pn+1 P1 - Pn+1 C =P1-Pn+1/r........(2) LOSS-RATIO In this paper the calculation for loss-ratio has been changed from the method presented by Johnson and Bollens2. The first loss-ratio to be calculated is a,; it is the initial production per unit of time after decline has set in divided by the difference between the initial and the second production rate. This loss-ratio is for the first time interval. After b (which is the constant change

Jan 1, 1957

By W. M. Mobley

THE coal industry in Alabama, centered in Birmingham, has pioneered coal-beneficiation practice in the United States. The nature of the coal seams and mining methods employed have necessitated use of equipment and methods best adapted to the local conditions. Although all of the 30 or more coal seams now being mined in the state receive beneficiation, only the three most important producers of coking coals, the Pratt, Mary Lee and Black Creek, are discussed in detail. Nature of the seams, washability characteristics and equipment used are given as examples of the extent of work and progress in this field. The coal seams in Alabama are relatively thin and pitching, making mining difficult and expensive. Most of them are characterized by thin partings of rock or shale in the seam itself, as well as laminations of bone and rash. Mechanical mining methods have increased the occlusions from roof and floor to such an extent that nearly all the coal mined in the state must receive some treatment before it can be put on the market. During the year ending Sept. 30, 1943,1 18,129,792 tons of coal were mined in the state and 14,364,177 tons, or 79.2 per cent, received treatment. Excluding from the total the 1,223,014 tons produced by small wagon mines and the hand-picked lump coal, the amount receiving beneficiation would be more than 90.00 per cent. This is, by far, greater than in any other coal-producing state. The earliest record of coal beneficiation in Alabama was the installation in 1890 of an experimental Lung washer by Alexander Cunningham, for the Sloss Iron and Steel Co. at its blast furnace in Birmingham .2 In 1894 the Jeffrey Manufacturing Co. introduced the English Robinson washer, a combination of a hydraulic classifier and centrifugal machine. Erskine Ramsay, who has contributed so much to the coal industry, saw its possibilities as well as its mechanical defects and soon had his inventive mind at work. He added a sludge tank of his own design, and many Robinson-Ramsay washers were installed in Alabama and other states. The Stewart jig appeared in 1900, followed by the Montgomery jig in 1910 and both have found extensive use. Increased interest in this field led to new designs, such as the American, Elmore; Burke and Faust. The first Baum-type Norton jig was operated in 1930 and within the last five years six large installations of this type have been made by the McNally-Pittsburg, Jeffrey and Link-Belt Companies. Wet-washing tables were introduced in 1922 but not extensively used until recently. The two most popular types are the Deister-Overstrom and Deister Plat-O. The coal-cleaning equipment used in Alabama has been relatively simple, yet efficient, but as the amount of impurities in the raw coal has been increased by mechanical mining and labor costs have become higher, much interest has been shown in sand cones, froth flotation and

Jan 1, 1945

By Katherine H. Walton

The research affiliate projects of the Continental Shelf Division of the Marine Minerals Technology Center concentrate on the development of technologies and methodologies for the exploration 4 and assessment of nonfuel continental shelf mineral resources within the U.S. Exclusive Economic Zone. Three of the FY 1990-91 research grants are summarized below. Scientists at the Center for Applied Isotope Studies at the University of Georgia have developed ?An Advanced Design for a Seafloor Gamma Isotope Mapping System? for the rapid collection of data on seafloor sediments. This system is designed to detect gamma radiation emitted by naturally occurring radioactive elements found in marine sediments. This data can be used to study seafloor lithology and has direct application in marine mineral surveys. The purpose of this study has been to redesign and calibrate the system for marine mineral survey work. Recent modifications of the sled design, gamma radiation detector, and supporting software have resulted in considerable improvements in sensitivity, functional operation, and data acquisition.

Jan 1, 1991

By Deepak Malhotra

INTORDUCTION Mining operations are unique In that they handle large volumes of water (millions of gallons) daily. The water contains dissolved metals, processing chemicals, organics, and other contaminants, There are several sources of water contamination at mine sites: mines, mills, tailings ponds, and Industrial/utility complexes. Utility waste water generally represents a very small portion of the total process water utilized in a normal milling operation and hence will not be addressed in this paper. Mine drainage can represent a significant amount, thus having an Impact on the recovery of metals, especially In Industrial minerals operations, and may have to be treated separately. The National Pollutant Discharge Elimination System (NPDES) effluent limits are becoming more stringent, thereby requiring mining operations to treat process water prior to discharge to the environment. The general trend Is to move toward a closed-loop waste system and treat only that small fraction of process water which Is to be discharged to public lands. The following section discusses the reasons for waste water treatment and the existing and emerging technologies for meeting NPDES effluent limits. REASONS FOR WATER TREATMENT Due to the diverse nature of the mineral Industry, process/waste water contamination problems as well as processing flowsheets are site specific. However, certain generalizations can be made specific to processing of different minerals: • Acid mine drainage Is a problem at sulfide/coal mines. • Cyanide contamination of water Is a problem at gold processing plants. • Organics can be a problem at mines using flotation oils. • Tolling ponds are generally acidic at sites processing industrial minerals such as silica sand and feldspar. The cost for water treatment Is viewed as an added cost of production. Hence, large mines are moving toward dedicating personnel to management of water resources in order to minimize waste water for treatment. Very often, mines having closed-loop water systems will treat waste water for reasons other than meeting NPDES regulations. These Include situations where process requirements dictate use of high-quality water for separation of minerals, neutralization of acid mine drainage water, and portable water for the mill. WATER TREATMENT TECHNOLOGIES Water treatment process has to be cheap and simple because It has to process large volume, and It does not directly add to the bottom line, namely revenue. The water treatment process development has to be site specific because the contaminants In the water vary from site to site. and discharge limits for water vary from state to state. The current technologies for wastewater treatment have been divided Into the following three areas: • Removal of heavy metals • Cyanide destruction • Scale control A brief summary of the current technology In each area Is discussed below. Removal of Heavy Metals The physical and chemical processes for heavy metal removal are summarized in Table 1. The most common and cheapest approach has been the precipitation of hydroxides at high pH followed by sedimentation and thickening of solids. The remaining solids can be removed by filtration. The pH is adjusted back to neutral, and the water Is discharged. This process is most commonly used wastewater treatment technology in the mining industry. The basic processes can be modified by combining other operations in order to meet the objectives of the specific site as illustrated In the following examples: • AMAX's Mt. Emmons treatment facility uses Lectro Clear® process where the precipitated solids are removed by electroflotation. • AMAX's Climax Mine water treatment plant used Ion exchange columns to meet the discharge limits on molybdenum.

Jan 1, 1992

The fourth annual Mine Rescue Evaluation program was held in conjunction with the 1995 Institute convention at Crested Butte, Colorado. The Mine Rescue committee is chaired by Lynn Busskohl and is but one of 16 such committees of the institute. In 1995 seven teams participated in the program. They were BHP Minerals, The Coteau Properties Company, Decker Coal Co., The Falkirk Mining Company, Kerr-McGee Coal Corporation, Sabine Mining Co. and Western Energy Co. [ ] Professional evaluators who provided challenging scenarios for the near 60 persons were Jack Knight of Pensacola, Florida; Dave Medick of Northwestern Resources, Jewett, Texas; Joe Nugent of Idaho Springs, Colorado and Jack Peleaux of Innovative Access, Evergreen, Colorado. Each team was comprised of seven members and one trainer representing the states of Montana, New Mexico, North Dakota, Texas and Wyoming. This committee challenges the incoming Colorado vice president to locate a team for the 1996 program in Durango, Colorado. Five different scenarios were presented the first day of evaluation and three the second. Each team was given the pertinent information to solve the problem as they assembled at the site. The realistic industrial related scenarios closely simulated the stress of actual rescue incidents and were going on simultaneously. Each team was unaware of the circumstances until arriving on the scene. Lynn Busskohl presented an overview of the Mine Rescue committee work at the Monday Institute welcome session and invited all attendees outside to view the various pretend rescue operations. Valuable suggestions were made by the team of evaluators following each scenario. These teams are providers of immediate rescue and medical care for accident victims at their respective properties. The members are prepared to act with immediate and professional knowledge to save lives and prevent further injuries. [ ] Many donors financially assisted with the 1995 program. They are: Blattner Constructors; Butler Machinery Co.; CMC Rescue, Inc.; Galls, Inc.; General Equipment; PMI-Petzel Distribution, Inc.; SafetyMaster; Skedco and TIC of Wyoming. An adder to the 1995 convention was golfing on Saturday, June 24 for three foursomes. This may become an annual event if there is sufficient interest. Team meetings, tests and swap meetings were attended by all participants during the Friday thru Monday program. A fun competition took place after lunch Monday followed by a training session. All events were chaired by Lynn Busskohl. On Saturday evening, June 24 a reception for all mine rescue participants and spouses who had advance registered for the social event. The RMCMI Board of Directors was invited to attend and meet with the teams. As convention attendees, all mine rescue committee members attended the Monday night country western reception and Bar-B-Q with their families. This was followed by an adult western dance evening. The Mine Rescue committee looks forward to a 1996 return to Tamarron near Durango, Colorado which was the site of the first evaluation program. Plans call for all convention housing to be at Tamarron.

Jan 1, 1995

By Dorothy B. Niell, O&apos

In its first three years of operations, the in-house programs of the continental Shelf Division of the Marine Minerals Technology Center (MMTC/CSD) have focused on the development of drill systems - technology and the improvement of techniques and applications of reconnaissance methods to marine mineral deposit characterization. Many of the technological advances made to date have been in direct response to specific requests from industry for drill systems needs, and from federal and state agencies seeking technical support for various research efforts. These cooperative programs have proven to be an extremely efficient and effective way for the MMTC to achieve some of the main program goals that were established for the organization at the outset: primarily, to encourage and assist U.S. industry in marine minerals research activities and to encourage cooperative work among research institutions, government agencies, and industry. The primary achievements of the MMTC/CSD to date include the development of the Remote Placer Drill System for rapid reconnaissance drilling of precious metal placer deposits (including both pneumatic prototype and hydraulic production

Jan 1, 1991

By John W. Carson, David S. Dick

The last few years have produced new methods of characterizing flow properties of bulk solids. Abrasive wear and particle attrition can now be accurately measured in a laboratory and scaled up to field condi¬tions. In addition, the effect of large par¬ticles on a material's flow properties (cohe¬sive strength, bulk density, wall friction) can be determined as well as the effects of var¬ious additives such as freeze conditioning agents. New developments have occurred with devices to improve the reliability of solids flow. Much attention has been paid to find¬ing ways, by using inserts, to provide a mass flow pattern with relatively shallow hopper walls. Such devices can also provide reli¬able in-bin gravity blending of bulk solids or completely nonsegregated discharge. Other developments have occurred in the area of belt-to-belt transfer chutes and sealing screws. The technology and hardware for running bench scale flow tests on bulk solids samples and transforming the results into reliable designs has been in existence for nearly 30 years (Jenike, 1964; Marinelli and Carson, 1986). It has been shown repeatedly that reliable materials handling systems can be designed to avoid the problems of no-flow due to arching or rat-holing, erratic flow, segregation, loss of capacity, or spontaneous combustion. Running flow properties tests and carefully designing a bulk handling system are not expensive, particularly when compared to downtime costs and continual flow problems. New developments in characterizing flow properties of bulk solids include: • a shear tester for measuring the properties of run-of-mine ores containing large par¬ticles; • attrition testers to simulate a wide range of flow conditions; • a tester to measure the wear rate of liners in bins, feeder parts, etc.; • a dustiness tester to measure the potential for dust and the effect of dust control meas¬ures; and • techniques for measuring the strength of frozen ores and the effect of freeze condi¬tioning agents. In the area of improving the flow of bulk solids, there are new techniques for ensuring reliable flow without using up excessive headroom. These include: • belt-to-belt transfer chutes to handle po¬tentially sticky, abrasive, and dusty ores; • designs for the interface between a bin/ hopper and apron or belt feeders to avoid hangups and minimize feeder loads; methods to feed solids reliably into a pres¬surized process; and designs for handling systems that will mini¬ mize attrition, avoid segregation, or auto¬matically blend materials together. Characterizing flow properties Large shear cell It has long been known that the cohesive strength of a bulk solid is due mainly to its fine fraction. However, the effect of the larger particles (that were assumed to re¬duce the strength) could not be measured. The development of larger scale (205 mm¬diam and 0.6 x 0.9 m or 8 in.-diam and 2 x 3 ft) shear testers has made it possible to measure the properties of a wider range of materials. Now cohesive strength measurements can be made with up to 100 mm (4 in.) particles. The results obtained from the large shear testers, together with the results of the nor¬mal shear tests on the fine fraction, are used in the design of reliable stockpile reclaim systems and crusher feed systems. A high percentage of large particles can reduce the measured shear strength of a bulk solid. However, segregation may alter the size distribution and should therefore be considered (Carson, Royal, and Goodwill, 1986). In addition, larger particles will

Jan 1, 1989

By Alfred Brooks

THE only oil produced in Alaska in 1923 was obtained from a dozen small wells, one of which was drilled during the year on the single patented tract of petroleum land in Alaska, in the Katalla field. These wells are owned by the Chilkat Oil Co., which finds a ready local market for its product in the form of gasoline produced in its own refinery. The search for oil has been continued, but except in the Cold Bay field there has been no drilling in new fields during the year. Drilling was in progress during 1923 at Pearl Dome, 18 miles from the coast. Here the Associated Oil Co. sank two wells, about 500 and 950 ft. deep, but suspended drilling in June. The Standard Oil Co., drilling on the same structure, reached a depth of 300 ft. by August and is reported to have reached about 700 ft. by November. The company began the, installation of a second drill in August. George C. Martin, who hastily examined the Chignik region, south of the Cold Bay field, reports that what is known of the geology near Chignik is not favorable to the presence of petroleum. Kirtley Mather, who made a geologic survey of the northern part of the Alaska Peninsula, reports that some of the structures and the formations are favorable to the presence of oil. A small seepage has long been known in the region near the mouth of Douglas River, which flows into Cook Inlet. Sidney Paige last summer made an examination .of the oil seepages which have long been known near Cape Simpson, 50 miles southeast of Point Barrow, the northernmost point of Alaska. He reports that there are two very large seepages emanating from small ridges about a mile apart and several miles from the coast. These are marked by flowing petroleum, and cover many acres. There is a very large accumulation of petroleum residue at these seepages. The surface exposures consist of clay shales with hard thin partings of calcareous shale which lie nearly horizontal, and are probably, of Jurassic age. Mr. Paige and his two sub-parties explored a large area inland from the Arctic coast between Cape Beaufort on the south and Point Barrow and Cape Simpson on the north. He himself ascended the Meade River for 150 miles. These surveys indicate a wide distribution of what is believed to be the formation from which the Cape Simpson seepages emerge, which is probably of Jurassic age. These rocks near the north Arctic coast are little disturbed, but are increasingly folded to the south, toward the mountains. No other seepages have been found, but what is known of the geology is not unfavorable to an oil field. This entire region lies in Naval Petroleum Reserve No. 4, and it was examined by the Geological Survey at the request and expense of the Department of the Navy.

Jan 3, 1924

By E. R. Atkins, G. H. Smith

Results of laboratory tests are presented to show that lire value of "m", in the Archie expression dernlined by the shapes of the particles in the system. Tile value of m "the shape factor", is constant for a system of particles of a given shape for a range of F - + values. Applying this concept, one can predict F - + relationships for mixtures of particles with different shapes, and these predicted relationships are useful in electric log interpretation. It is suggested that an equation of the form 1/F -10mcan be used to describe the properties of natural formations containing varying amounts of sand and clay. From this work and values of "a" and "m" reported in the literature, it appears that in many cases rocks in the same geological horizon have a common primary porosity but contain varying amounts of a particular clay. It is concluded that the equation can be applied to a rock-water system only when values of "a" and "m" have been established for the particular system. INTRODUCTION The petroleum literature contains many reports of the results obtained by determining formation resistivity factor F and porosity + of rock samples from oil fields all over the world. The usual practice is to use data from a large number of samples from a number of fields to find an average relationship between F and +. Several such average relationships have been advanced. In the absence of data on a particular formation or field, it has been the practice to use the average relationships to give a rough approximation of the F - + relationship. The purpose of this paper is to report on basic relationships that exist between F and + for naturally occurring particles in water solutions. Other workers' have found the same relationships apply to the diffusion of hydrogen through packed beds of dry particles. In the work discussed here, relationships for application to unconsolidated sands or shales containing mix- tures of particle shapes are derived. These relationships, developed for unconsolidated formations, may apply to consolidated formations. EXPERIMENTAL To evaluate F- relationships for unconsolidated rocks, the results of laboratory measurements on simple slurries of clay or sand will be used. Such laboratory studies are concerned with the electrical behavior of water-containing rocks. The wet rock constituents are electrically similar in slurries and in rocks. Archie2 defined formation resistivity factor as All resistance measurements were made using a 1,000-cycle impedance bridge with an oscilloscope as the null detector." The accuracy of this bridge was better than * 0.15 per cent. For the particular apparatus employed, no additional reactance was required to achieve balance for samples with resistances between

By J. P. Sieverson

The Comprehensive Environmental Response, compensation, and Liability Act (CERCLA -commonly referred to as Superfund) was passed into law in December 1980 in the wake of such incidents as Love Canal and the Valley of the Drums. Superfund was originally perceived as a way of cleaning up spills of hazardous substances and/or cleaning up abandoned hazardous waste dumpsites. In February 1981, Michael Cook, EPA deputy assistant administrator for hazardous emergency response, called Superfund "a tremendously powerful law. It could revolutionize the way the environment is protected, but we certainly don't intend to realize the full potential of the law for some time." These words have proven prophetic for Asarco's East Helena Smelter.

Jan 1, 1988

By Herbert Hoover

IT is always a pleasure for me to join in the Ameri-can Mining Congress, for not only has my own professional life been closely linked with the industry, but the Secretary of Commerce is specifically enjoined in the organic act creating the office to promote and foster the interests of the mining industry. And it is a vital part of our national life. It is one of those indus-tries without which. the nation could not go on for a week. It ranks second only to the agricultural industry in its contribution to our raw materials. Its production amounts to nearly 6 ½ billions annually, providing direct support to probably ten millions of our people through employment to about two million workers. But the in-dustry has a greater importance than even these figures indicate, for with agriculture, forestry, and water power it furnishes the raw materials upon which the whole work of our civilization rests. When the raw ma-terials of our mines emerge. from manufacture with the added expenditure of labor and capital upon them, they have a wholesale value of over fifteen billions of dollars. And in this, the second stage of their application, they give employment to another two million workers and support to about ten million more of our people. A large portion of these manufactured commodities must filter through the retail trade; their total value when delivered to the consumer exceeds twenty billions of dollars. And from this distribution arises the support of many more millions of our people. It is estimated that the products of agriculture when they reach . the consumer, with transportation, manu-facturing, and distribution costs added, have about the same value as the mineral industries-each of them thus contributing about one-quarter of our total na-tional income. No other continent has demonstrated its possession of such a magnitude of minerals as has ours, and such a bountiful distribution over our whole land. But our mineral resources differ in one essential from our other natural resources-they are not renewable. Agricul-ture, forests, and water power replenish their supplies from season to season. Some people conclude from the non-renewable character of the mineral supply that they must shortly be exhausted. The practical question is ,one of time, and time in these matters needs to be measured in generations, and apprehension of exhaus-tion needs to be tempered with many probabilities in-cluding the advance in technical methods of extraction. In some of our minerals, such as coal, iron, and building materials we can, through a knowledge of their geologi-cal structure and occurrence, make fairly good estimates of our reserves. We. know that they will outlast many generations of Americans. In non-ferrous metals and oil, geology affords us no great basis for an estimate of future supply. We only know of the occurrence of minerals of this type by actual exposure of them, and we can thus make no estimates except upon reserves which have been proved by actual development by the process of mining. To develop them ahead merely for national satisfaction of assured future supply would imply an unbearable waste of capital. The consequence is that in these groups there is never a demonstrable assurance of more than a few years' supply ahead of us. Yet we have never failed from year to year to find new deposits and extension of old deposits.

Jan 1, 1928

By Peter J. Maxworthy

INTRODUCTION There is no hard and fast rule on whether functions within a company, diversified or otherwise, should be strongly centralized or decentralized. In all diverse organizations, there are certain basic functions which remain common (or central) to each element of the business, viz: Personnel Management Cash Management Taxation Management Legal Planning Accounting Standards It would follow that each of these common factors requires some supervision at a central level to ensure that overall group objectives are met. It is true that other functions including: Industrial Relations Marketing and Distribution Production Research and Development Purchasing Management Accounting may also be common to each element of the organization. However, there is far less commonality in the degree to which these functions are central to the efficient performance and financial well-being of the business. Role of Operating Units The resources of operating centers may be viewed as a bank of funds, the nature of which can be changed from time to time, but the employment of which must provide for ongoing increases in the net worth of the total enterprise expressed in terms of market values. Operating units are required to continually review products, methods, and opportunities and to monitor avenues for incremental investment--all with a view to attaining the necessary additive net present value of future cash flows of the enterprise. Operating units should be permitted sufficient autonomy to enable the best use to be made of the skills and experience of the people it employs in order to produce a return appropriate to the value of assets employed. Role of Head Office The head office will typically comprise a specialist group--the leaner the better if one strongly adopts the decentralist approach--often acting as Service Centers but also performing a control function in the corporate sense. The head office function is a cost center. It may be instrumental in developing strategies for increasing revenues or reducing costs on a group scale, but it does not generate revenue. Every dollar spent on this function is an extra dollar to be generated by the operating centers in order to achieve an increase in corporate wealth. TREASURY MANAGEMENT Treasury management is concerned with the provision of finance, cash-flow management, and risk analysis. Each decision taken within the enterprise has a cash implication. It follows that a well-integrated central Treasury function can, in all likelihood, produce economic benefits. The degree to which the function should be centralized depends largely upon the unique nature of the operating units it is servicing. Levels of ownership, the calibre of unit operating managers, and the nature and geographic distribution of the business are all factors determining the degree to which the Treasury function is centralized. In the case of Peko-Wallsend, the Treasury Department is small, comprising four people. While divisional cash-flow management is largely decentralized, Treasury is responsible for the daily management of funds surplus to the immediate needs of operating units. Treasury also operates as central banker and provides funds to

Jan 1, 1985

By B. W. Dyer

At about 8:30 o'clock on the morning of March 8, 1924, an explosion occurred in the Castle Gate No. 2 Mine of the Utah Fuel Company, Castle Gate, Utah, and 171 men lost their lives. The explosion was caused by the ignition of a comparatively small body of gas and was propagated throughout the mine by fine coal dust which had accumulated on the roof and ribs of the mine and by coal dust made by the explosion itself. Castle Gate No. 2 Mine was one of the best kept mines in the state and it was believed not only by the officials of the Utah Fuel Company, but by all others connected with the coal industry of the state that this was one of the safest mines in the entire state. The state had not been visited by a catastrophe for over twenty years and it was a general belief that the mines were kept in such condition that a catastrophe was almost impossible. During the preceding twenty years new mining officials from other fields had entered the state and seeing that sprinkling as done in Utah was far more elaborate than in most other coal mining sections of the country, caused them to believe that they were keeping their mines in an absolutely safe condition. When coal -mines suffer no mishap during a period of twenty years the general attitude relative to safety may become somewhat lax, not only with the operating officials, but also with the State Inspection Department. However, there were some who were more keen to appreciate the hazards of Utah coal dust and who predicted that if Utah mines were kept only damp but not wet, some day the state would be shocked by the news of a dreadful disaster. In a paper prepared and read before the Salt Lake City Chapter of the American Institute of Mining and Metallurgical Engineers in 1924, Mr. D. Harrington stated: "The writer had his first mining work in Utah mines spending nearly ten years in Utah, starting just after the Scofield explosion in 1900. After having been absent from the state for about eight years upon returning and spending a few days in a few properties, there appeared then to be a definite relaxation as to precautionary methods especially against dust; some of the properties which in 1900 to 1910 would have stopped work if for any reason water was not available for sprinkling purposes, were in 1918 definitely dry in many places, and in some instances there was also definite relaxation as to shooting regulations, some properties with electric shooting systems were allowing firing of certain shots while the men were in the mine. The Utah coal. dusts are too inflammable and explosive to allow of taking any chances and unless up-to-date and carefully maintained, the Utah coal mining world will hear to its dismay, that the very excellent record of the past twenty-three years as to explosions has been shattered. Hence, possibly it was not altogether a complete surprise that such a disaster occurred in Utah, but it was a surprise to many that it occurred in one of the best kept mines in the state and it was that fact that led the coal mining men of Utah to believe that the state coal mining laws should be modified.

Jan 1, 1925

By E. J. Gleim

"Information gathered during recent months by field men of the U. S. Bureau of Mines shows that in one State alone there have been 71 fatalities from electrical causes during the last 51/2 years, of which 55 were from contact with mine trolley wires operated at 250 volts or less, direct current. The 1928 law relating to the guarding of trolley wires in the-mines of this particular State reads: ""All trolley wires carrying a voltage of class 2 must be properly shielded except where the same are at least 61/2 feet above top of rail."" Class 2 voltage is defined as being ""between 300 volts and 600 volts direct current, or 240 volts and 480 volts alternating current."" From this it may be inferred that no guards are required, for 250-volt trolley wires, and the natural conclusion to be drawn is that the lack of guards or shields must be held responsible for these fatalities. To prevent fatalities from this source, it has been advocated that every foot of trolley wire in mines should be guarded. While some such drastic step may appear to be amply justified, a closer examination of the records shows that lack of guards is not entirely responsible but rather that carelessness and neglect in the observance of certain well-established simple rules concerning installation and location of trolley wires must also bear a share in the responsibility. In -other words, if trolley wire is installed carelessly and its maintenance neglected, failure may be expected of any guards that have been put up.There are a-number of factors affecting safety as related to trolley wires in mines, among which the following may be enumerated.1. Installation relative to track and passageways.2. Guarding.3. Maintenance.4. Discipline.Acknowledgment is made to D. Harrington and K. L. Marshall of the safety division of the bureau for assistance given in securing data on cost of installing guards for trolley wires.The statement that fatalities should not be charged in every case to lack of guards is supported by the following example: A man operating a locomotive was electrocuted when the trolley wheel jumped the 250-volt trolley wire and allowed it to sag against his shoulder. He was sitting in the regular place provided in the locomotive, but the wire was 11 inches inside of the rail and only 39 inches above it where the wire touched him, or 11 inches from the roof at a distance of 12 feet from the nearest hanger. The accident occurred between two hangers 44 feet apart, and the trolley wire was inside the rail over the entire distance, being 2 inches inside at one hanger and 10 inches inside at the other hanger. A bolt in the roof indicated that there had been a hanger at one time between the two on the 44-foot span.This example is a violation of good practice in the installation and maintenance of trolley wire. In the first place the wire should have been outside instead of inside the rail. In the second place there should have been at least one intermediate hanger so that the span would not be so great and the sag would be reduced. Furthermore, it is possible that the wire was not taut enough even when the intermediate hanger was in place.To provide a degree of safety for men in the mines certain coal-mining States, recognizing the need, have enacted laws to regulate the installation of trolley wires. These limit the distance that the wire must be kept outside and above the rail. Thus, the 1927 mining laws of Ohio specify that:"

Apr 1, 1932

By E. P. Abrahamson

The effect of transition element binary solid solution additions upon the re crystallization temperature of nickel has been investigated. All additions raised the re crystallization temperature. Both the rate of change of re crystallization temperature with at. pet solute and the limit of initial linearity are found to correlate with the free atom ground state outer electron configuration of the solute element. A comparison of all of the correlations for the transition elements studied has yielded a set of empirical relations, which allows the prediction of the effect of dilute binary transition elements on the recrystallization temperature of other transition elements. The work of Abrahamson, et al.1-7 on dilute binary solution alloys indicated a correlation between the free atom ground state electron configuration of the solute and both the brittle-ductile transition and re-crystallization temperature. Further, it has been shown3,4 that the limit of initial linearity may also be correlated with the solute electron configuration. Since previous studies have dealt with bee and hexagonal base elements, this study is made to note what effect, if any, the fee base structure might have. Nickel also serves to give a solvent configuration which will allow the comparison of all of the transition element solvents. Olsen8 has studied the effect of some trace elements upon the recrystallization of nickel. He included only Ti, Zr, W, Mn, and Co of the transition elements. The differences in change of recrystallization temperature were attributed to the solute atom size and to the solubility of the solute in nickel. PROCEDURE All alloys were made using 99.9 + pet Ni with 0.003 C, 0.015 Fe, 0.007 0, and 0.0007 H. The solute elements were 99.9 + pet pure. According to the published binary phase diagrams9 and metallo-graphic examinations at X750, all solute elements were in solid solution. The alloys were arc melted and remelted four times in the form of cubic 200-g buttons under an argon atmosphere. They were then hot forged at 800oC to 0.750 in. diam, machined to 0.60 in., vacuum annealed for 1 hr at 700°c, swaged to 0.40 in. and annealed at 700oC for 1 hr in vacuum. The grain size was checked and found to be 77 * 20 grains per sq mm. The specimens were then swaged to 0.187 in., yielding 76 ± 1 pet cold work. All alloys were then chemically analyzed for the solute addition. The interstitial contents remained at the values of the starting material when checked on random alloy specimens. The swaged rod was cut into 8.25 in. lengths and heat treated in a gradient furnace for 1 hr. The gradient was maintained at 250" to 850°C over an eight inch length, recorded by twelve thermocouples. Control was ± 3oC, accomplished at the hot end. The recrystallization was determined metallo-graphically over the entire specimen. The criterion chosen was that point on the specimen showing the first recrystallized grain at a constant magnification, X200. Specimens were repeated, and the agreement was found to be generally ± 3oC.

Jan 1, 1962