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By S Arnold

Properties of the soil profile fundamentally control water-limited ecosystems. Soil water availability affects vegetation dynamics of plant communities, but is also affected by these communities in return. Understanding this eco-hydrological interplay and the role of physical soil restoration is crucial for successful rehabilitation and management of post-mining landscapes in semi-arid areas. However, uncertainties exist in both the mathematical description of plant communities within ecological submodels and the predictability of future rainfall events. This study uses information gap decision theory combined with an ecohydrological system model to investigate how both uncertainties impact decision-making in the context of ecosystem rehabilitation. A range of management strategies are investigated to identify the optimal soil thickness for successful rehabilitation of native plant communities in Central Queensland. The results emphasise that thicker soils can counterbalance uncertainty in mathematical description of plant communities by increasing the simulated survival probability of plant communities. However, the influence of thicker soils on the robustness of plant communities against a change in future rainfall amount is rather marginal. By allocating an economic value for restoring a particular thickness of soil layer, these results can be used to evaluate the costs of ecosystem re-establishment with regard to two target measures - the survival probability of the plant community and their robustness against climate change.CITATION:Arnold, S, 2012. Finding optimal soil restoration strategies in the face of uncertain future rainfall amount, in Proceedings Life-of-Mine 2012 , pp 91-96 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By James M. Barker

The borate deposits of Death Valley, first exploited in 1882, were a major world source of boron-bearing products until shortly after very large deposits near Boron, California (Kramer) came on stream in 1926. Borate mining in Death Valley then became moribund, with most extant deposits held as reserves backing Kramer. Tenneco began borate operations following acquisition of claims in 1967 and is the only active borate producer inside Death Valley National Mon¬ument. Borate ores, confined to the lower Furnace Creek Formation (early to middle Pliocene), initially precipitated in a shallow lake fed by boron-rich volcanic hot springs associated with the Basin and Range province. Later diagenesis and remobilization plus regional folding, faulting, and erosion altered and complicated originally simple borate mineralogy and distribution. Dominant ore minerals are ulexite (NaCaB509.8H20), probertite (NaCaB509.5H20), and colemanite (Ca2B6011.5H20). Tenneco currently operates two open pits near Ryan, California. Mining is by bulldozer-pushed scrapers hauling waste and front-end loader/off-highway truck combinations for ore and waste haulage. Archeological, environmental, and aesthetic considerations influence both mine plans. Boraxo Pit, opened in 1970, has deep ore (stripping ratio 10 to 13:1) which occurs along a fault and as beds in shale on the hanging wall. Problems include pit wall instability (adverse bedding), non¬ripable calcareous shale (11,000 fps), and mixed ore separation. Sigma Pit, opened in 1975, has shallow (stripping ratio 1 to 1). low dipping, bedded ore in shale. Massive ulexite and "granular" un- cohesive colemanite present problems in mining and milling. Colemanite is crushed to -6 inches, washed, dried at 350°F, then calcined at 800°F with 100 tpd capacity. Crushed (-6 inch) ulexite or probertite is Raymond milled to customer specifications with a capacity of 1000 tpd.

Jan 1, 1976

By F. W. Horton

This paper covers the salient features of the occurrence and mining of sheet mica in the United States and the preparation of mica for market; presents the results of a study of the physical properties of domestic and foreign micas, which the author hopes may he of interest to every mica user, as it definitely answers many questions as to the suitability of various minas for particular purposes; and discusses mica-trade conditions and the future outlook for the domestic mica industry. ACKNOWLEDGMENTS The author takes pleasure in acknowledging his indebtedness to J. R. Thoenen, of the United Stator Bureau of Mines, under whose guidance the work reported herein was performed, and to Frank L. Hess, also of the Bureau, for information on the geological and mineralogical characteristics of mica-bearing pegmatites.

Jan 1, 1935

By Mark S. Sanders

This report is a review and synthesis of the published literature dealing with personal equipment items used by low seam coal miners. This report reviews the following items of equipment: headgear, outer garments, respirators, cap lamp, gloves, knee pads, footwear, boots, helmets, ear protection, eye protection. Recommendations for further research and development are included.

Jan 1, 1978

By AIME AIME

FEATURES of the second fall meeting of the Petroleum Division for 1941, held at the Ambassador Hotel, Los Angeles, Oct. 29-30, were the forum on the Paloma Plan on Thursday after- noon, the large attendance from east of the Rockies, and the dinner on Wednesday evening sponsored by the Southern California Section and at which President Suman spoke on the strategic minerals and metals situation. The attendance was large and the technical fare uniformly good ; the presiding officers had the proceedings well in hand at all times and kept things humming. Some- times it was necessary to taper off the discussion because of pressure on time. All this was due to careful groundwork before the respective sessions. These presiding officers deserve citation: L. W. Huebel, Howard Pyle, E. K. Parks, Carlton Beal, E. G. Trostel. R. W. French, Jr., John Dodge, and H. N. Marsh. The Los Angeles local commit- tees and the Southern California Section deserve much credit for the arrangements, which were recognized by suitable resolutions at the end of the meeting.

Jan 1, 1941

By J Vann

The philosophical context of many activities in mine geology can be an important lever in adding value to operations. For mine geologists (including resource and grade control geologists) we argue that the tasks of problem formulation, observation and data collection, interpretation and modelling invoke various philosophical considerations whether the practitioner is aware of them or not.Constructing testable models to explain reality is the definitive aspect of any activity claiming to be ‘scientific’. A primary goal of mining geology is to build models that accurately predict reality to an acceptable degree and these include litho-structural, stratigraphic, grade control, resource or reconciliation models. What’s more, in mine geology we are often able collect additional drill samples or access new underground openings, for example, that can provide relatively rapid feedback on how predictive, and therefore useful, our models are. In this paper, we describe the key philosophical frameworks proposed for conducting scientific investigations, including falsification, the method of multiple working hypotheses and structural concepts of scientific theory. The strengths and weaknesses of these approaches are discussed and an attempt is made to relate them to activities undertaken by mine geologists. Common perceptions of what constitutes the scientific method have been dominated by how scientists do experimental physics and chemistry in particular. There are very important differences in the types of problem confronted in these experimental sciences compared to the ‘historical sciences’, such as geology, where the processes studied are unique and only evidential traces of past events are available. The philosophical implications of attempting to validate numerical geological models, such as resource estimates are also briefly considered.Some practical conclusions are drawn about how mine geology activities can be better implemented if practitioners are cognisant of the importance of philosophical considerations when attempting to gain new knowledge through a scientific investigation. We believe that the implications for creating additional value to a project or operation can be very significant when geology is applied by a practitioner with an understanding of the philosophical basis of the activities we think of as constituting a scientific investigation.Remember that all models are wrong; the practical question is how wrong do they have to be to not be useful? (Box and Draper, 1987, 74 p).The demand that theories be highly falsifiable has the attractive consequence that theories should be clearly stated and precise. If a theory is so vaguely stated that it is not exactly clear what it is claiming, then when tested by observation or experiment it can always be interpreted so as to be consistent with the results of the test. (Chalmers, 1999, 67 p).

Aug 22, 2011

By A. C. Bigley

Before going into this subject, I would very much like to call to your attention some past history on patents granted by the United States Patent office that involved ammonium nitrate. On February 10, 1885, a patent was granted to Russell S. Penniman. "The object of this invention is to securely protect ammonium nitrate against deliquescent and to maintain it in substantially its normal disintegrated condition, so as to afford a new product suited for ready use in the manufacture of high explosives, and enable the immediate admixture thereof with any of the well known explosive substances or compounds heretofore employed. 'Whether the nitrate be thus granulated or otherwise reduced to a granular or divided condition, it is then thoroughly mixed with about twelve (12) percent of the fluid or semi-fluid carbonaceous protecting medium, which forms a readily applied jacket or coating for the granules of nitrate and also serves as a carbonaceous element in such explosive compounds as it may thereafter be employed in."

Jan 1, 1958

By C. Piribauer, E. Feichtenhofer, A. McEneaney

"As part of a major diversification project, RHI AG, through its plant in Drogheda Ireland, has developed a Caustic Calcined Magnesium Oxide (CCM) for use in the Cobalt (Co) & Nickel (Ni) hydrometallurgical extraction industry. In the course of the project, the company investigated the chemical and physical properties of a number of different Magnesia’s used in Co & Ni hydrometallurgy applications and has been able to determine the important parameters for a successful Magnesia for this application. A number of live plant trials have confirmed the results of this testwork and the company is now proceeding to produce this product in commercial quantities at Premier Periclase Ltd., the RHI AG plant in Drogheda, Ireland. This paper will outline the development work conducted by the company and highlight the important chemical and physical properties that make a successful CCM. Much of the research was conducted at the RHI Technology Centre in Leoben, Austria. In addition, a number of external laboratory studies were conducted on behalf of RHI AG. The result of this work has allowed the company to develop a Magnesia product with optimised properties for use in the Cobalt and Nickel hydrometallurgical extraction process.INTRODUCTION Premier Periclase is part of RHI AG, a globally operating supplier of refractory products, systems and services, headquartered in Vienna, Austria. The company produces Magnesia from seawater at its plant in Drogheda, Ireland. While the main focus is on production of refractory grade Dead Burned Magnesia for the steel industry, the plant also produces a number of different grades of Caustic Calcined Magnesia as well as Magnesium Hydroxide products. As part of a major project to diversify the company’s product base, the use of CCM in the Cobalt (Co) & Nickel (Ni) hydrometallurgical extraction industry was investigated. One of the company’s highly reactive grades of Caustic Calcined Magnesia was found to be particularly suitable for this application. In an effort to understand what makes a successful Magnesia for hydrometallurgy the chemical and physical properties of different Magnesia’s used in Co & Ni hydrometallurgy were investigated. This paper and conference presentation outlines the findings of this process."

Jan 1, 2017

By W. L. EGY, GEORGES. RICE, L. M. JONES, J. K. CLEMENT

This report has been prepared, not only for the purpose of recording the results of the first series of coal-dust tests conducted in the experimental mine of the Bureau of Mines, but also to place before the mining public a description of the mine and an account of the objects sought in its establishment. Soon after the organization of the technologic branch of the United States Geological Survey, J. A. Holmes, then chief of the branch, concluded that for the solution of various problems relating to the causes and prevention of mine explosions it would be best to carry on large-scale tests in a mine rather than in a surface gallery. The idea of utilizing the underground passage of a mine for making explosion experiments did not at' first meet with general approval among investigators in this country or abroad. Many thought a mine passage was not a proper place in which scientific tests could be conducted, as great difficulty in controlling conditions was expected. However, after all arguments for and against such an investigation had been carefully considered, plans for opening an experimental mine were definitely adopted by the Bureau of Mines in 1910, and an allotment of funds was made to carry out the project. The first endeavor was to find an existing mine suitable for the purpose, but the mines offered by owners were either worked out, were wet, had poor roofs, or presented complications of various kinds, so that it was finally decided to open a mine if a site could be obtained having natural conditions that would fill the various requirements. A most desirable location was found on property of the Pittsburgh Coal Co., near Bruceton, Pa. The president of this company, Mr. W. K. Field, the general manager, Mr. G. W. Schluederberg, and the chief engineer, Mr. E. J. Taylor, rendered every possible service in

Jan 1, 1913

By R. R. Klimpel

The industrial processing of ores containing precious metals such as gold is generally very mining site specific, e. g. McQuiston and Shoemaker (1985), vanZyl et. a1. (1988), Fuerstenau and Hendrix (1990), and Hausen et. a1. (1990). The variety of various mineral processing techniques employed is extensive and includes size reduction, size classification, gravity separation, roasting, cyanidation, chemical and/or bacterial leaching, ion exchange and/or solvent extraction, and froth flotation. Gold occurs in the earth's crust on the average in very low concentration estimated by various sources to be between two and five parts per billion. For a specific ore deposit to be considered as an economic source of gold, generally a concentration of near one part-per million (one gram / Mton) or more is required. From a mineralogical viewpoint, gold often occurs in its native or free form. However, it can also occur as gold compounds of telluride, antimony, and selenium contained within either sulfide minerals such as pyrite, arsenopyrite. and pyrrhotite or, to a less extent, within silicate, oxide, and carbonate minerals. In many locations, alloying of gold with silver is found. The optimal processing method for recovering gold is determined by many factors such as the mineralogy of the gold bearing minerals as well as the associated mineralogy of the gangue minerals, the type of liberation profile of the gold bearing minerals upon' size reduction, and the particle size of the gold itself. Free or native gold particles can vary in size from the extreme of large nuggets to very finely disseminated gold associated in a complex sulfide mineral matrix. Typically free gold particles of several hundred microns or larger are efficiently recovered by one or more of a number of gravity based techniques due to the large specific gravity differential of gold (19.3 to 15) versus typical gangue minerals (5 to 2.7). When gold is associated with a sulfide (usually pyrite) matrix, historically most industrial plants involving size reduction and subsequent liberation have operated in a size range of 50 to 80 percent less than 75 microns. Grinding finer than this has been normally not economical unless the ore has a high gold content in the feed ore.

Jan 1, 1998

By Francisca San Martin, Tomas Vargas, Willy Kracht

"In Cu-Mo deposits it is usual to find considerable amounts of pyrite (FeS2). When processing this kind of ore by flotation, pyrite is rejected using lime to increase the pH to alkaline conditions (pH ~10.5). In the case of using seawater without pre-processing, i.e., raw seawater, the lime consumption increases dramatically and the recovery of molybdenite drops due to the precipitation of magnesium hydroxide on its surface. In order to avoid these negative effects, alternative ways of depressing pyrite should be considered.The current work introduces the use of Acidithiobacillus ferrooxidans, bacteria commonly used in bioleaching, as an alternative to depress pyrite in seawater flotation. The paper presents the results of biodepression in three systems: fresh water, water with added sodium chloride at 35 g/L (which corresponds to the salt concentration in seawater ) and seawater. The results show that it is possible to bio-depress pyrite with A. ferrooxidans in natural seawater pH (7.8-8.2). A similar behaviour is observed when running the experiments in fresh water, and in water with sodium chloride added.INTRODUCTIONWater is a scarce but essential resource for human development. The main reason for this scarcity is that, although 70% of the earth's surface is covered with water, only 3% of the total is fresh water and an important part of this water is frozen, so that only 1% of fresh surface water can be used for human activities. In Chile, most of the mining activity is concentrated in the north of the country, located in the Atacama Desert, considered the world's driest desert. That is why some mining companies have chosen to use seawater in their processes. For example, Esperanza (Antofagasta Minerals), and Sierra Gorda (KGHM International) use raw seawater in their flotation processes."

Jan 1, 2016

"With millions of dollars and thousands of lives at stake, the Iron Ore Company of Canada (IOC) turned to a private wireless network for help.IOC needed a network that possessed the ability to adapt to changes in a nanosecond and to function seamlessly in the most rugged of environments.Canada’s largest iron ore producer required a private wireless network powerful enough to support all mine applications and deliver all data to one central point — without any existing cellular/3G/Wi-Fi coverage.Operations at IOC, a leading global supplier of iron pellets, involved dispatch, drill management and equipment monitoring, pump control and remote video that must service three distinct pits. Due to its setup, the facility does not offer a great deal of flexibility for transmitting signals.IOC serves a robust customer base made up of North American, European and Asian steel producers. It also employs nearly 1,900 people. Catastrophic death and destruction are two very real potential consequences of system communication failure.Technology for tough terrainKinetic mesh technology was born in the wake of the 9/11 terrorist attacks on the United States, one of the most high-stakes emergency situations in U.S. history. The failure of the communications infrastructure on a massive scale that day underscored the need for networking technologies that could provide service even in the most chaotic of conditions.Kinetic mesh networks allow organizations to deploy networks at sites where communications infrastructure has been compromised, as well as quickly establish networks in places where they did not previously exist. Kinetic mesh networks have also demonstrated a better ability to adapt to network changes on-the-fly versus other types of networking technologies."

Jan 1, 2015

By Hugh Douglas

This paper discusses the financial health of the U.S. mining industry and its ability to meet the future raw material requirements of this country in the context of resource independence. The title of this paper begs several questions, and three will be raised here. The answers to them will form the basis for discussion. The three questions are: What does one mean by resource independence. How is the U.S. mining industry defined. How is financial health measured.

Jan 1, 1977

By Alfred L. Ransome

The consumption of slab zinc in the United States increased sevenfold in less than a half century since 1900. Therein is reflected the innate characteristics of this versatile and nearly indispensable nonferrous metal whose use has grown at more than twice the rate of industrial production. The total metal consumption was substantially stimulated during the two World War periods, which were likewise marked by notable changes in use pattern accompanied by shifts in geographic distribution. This information circular summarizes basic data collected for many years by the Bureau of Mines, but in particular presents for the 1940-45 period details derived from the comprehensive slab zinc consumption survey inaugurated in 1940. The total consumption of slab zinc has been broken down into four major categories galvanizing, brass products, rolled zinc, and zinc-base alloys -- with minor applications grouped under a fifth heading, other uses. Ex- cept for the inclusion of zinc-base alloys with other uses before 1926, the above-named segregation has been shown for the entire period 1900-45. 11- though a substantial tonnage was taken by all groups in all years, there were large shifts in the use pattern in both World War periods. In both, the Allied Powers depended heavily on the United States for zinc-bearing products, especially those required by war industrius. The departures from usual uses were, however, much more marked during the second than in the first period, mainly because the United States could not have met the tro- mendously expanded war-materiel demands had the greater slab zinc needs of a period of high industrial activity been supplied. The geography of consumption is known in detail only for 1940-45. Even in that short period, substantial shifts are observable, largely the reaction from conversion to war production in 1940-41 and reconversion to peacetime consumption in 1945. However, there is so evidence of other shifts in consumption centers that appear to reflect longer-term develop- ments.

Feb 1, 1948

By W. M. Armstrong

This paper compares research on development efforts in various countries, consideration being given to gross expenditures, manpower involved, source of funds, sector of performance and type of activity. The Canadian R & D activity is then reviewed, particularly as applied to the industrial sector, the problems of applied research in Canada are discussed and some remedies are suggested.

Jan 1, 1968

By R. R. Stone

"This paper will examine the role of debt and equity in project financing and will illustrate the impact on the return to the project sponsor of each type. Conventional debt sources will be examined, as will product purchaser advances, foreign export-import bank loans and lease financing. The paper will review guarantees, charges against the project, dividend restrictions and other commitments. It will also discuss various features of sales contracts and the degree to which they can assist in securing financing. IntroductionThe cost of bringing new mining projects on stream is escalating significantly more rapidly than general rates of inflation. Reasons for this include the higher costs of safeguarding the environment and ensuring the health and safety of workers. The need to develop properties in more remote areas is also a significant factor. These higher costs have not been matched by increases in metal prices, making the task of financing these projects ever more difficult. At the same time, the imagination of borrowers and lenders seems boundless, and innovative schemes for financing projects are constantly being unveiled.It is probably safe to say that no two projects have ever been financed in precisely the same way and the number of financing options for any project is limited only by the imagination of the sponsors themselves. The objectives of the project sponsor represent the most important factor in determining the scope of possible financial arrangements. For example, the sponsor may wish to maximize over-all company leverage by isolating each of its projects in separate companies. In so doing, it hopes to facilitate more ventures than would otherwise be the case. These objectives point toward true project financing. Additional objectives may be to develop a number of its properties by joint venture and to reduce the amount of debt on the sponsor's balance sheet. Those sponsors whose objectives include minimizing over-all financing costs will wish to increase the number of financial options and, as a result, will not be so concerned with effecting true project financing. This approach may also provide ""greater certainty that tax benefits are utilized quickly."

Jan 1, 1980

By Sidney Katell

This; report, covering the period January 1965 through December 1965, is a continuation of a series that began with the publication of Information Circular 7516 in October 1949. It is the seventh in a series of reports prepared in cooperation with the American Association of Cost Engineers. The abstracted articles are concerned with all phases of cost engineering in the field of chemical and petroleum plants and related subjects. They are from the following sources: 1. American Association of Cost Engineers Bulletin. 2. Bureau of Mines Information Circulars. 3. Bureau of Mines Reports of Investigations. 4. Chemical Engineering. 5. Chemical Engineering Progress. 6. Chemical Week. 7. Coal Age. 8. Coal.3 9. Cost Engineering. 10. Hydrocarbon Processing and Petroleum Refiner. 11. Industrial and Engineering Chemistry. 12. Nucleonics. 13. Oil and Gas Journal. 14. Petroleum Management. 15. World Oil.

Jan 1, 1966

By W. L. Saunders

(Wilkes-Barre Meeting, June, 1911.) I. INTRODUCTION. IT is now generally admitted by experts that at least so far as rapid progress is concerned the Alpine system of tunnel-driving is superior to any other. This is perhaps natural in view of the record of experience in driving tunnels through the Alps. These great mountain-chains cannot be treated in the ordinary way by shaft-sinking and driving headings, thus multiplying the points of attack. The work must be done from the ends only, hence speed in driving is of the utmost importance; and, as necessity is the mother of invention, the concentration of effort to make progress has resulted in an organization and in mechanical appliances that have produced results so much in excess of the usual practice, even in America, that a discussion of the subject in detail should be of much value to the engineer and contractor. The first Alpine tunnel was the Mont Cenis, length 7.5 miles, driven with a progress that averaged about 7.75 ft. per day. Next came the Saint Gothard, 9.5 miles long, 18 ft. per day; Arlberg, 6.5 miles long, 27.25 ft. per day; Simplon, 12.25 miles long, 36 ft. per day. The figures represent progress when driving from two headings, so that by dividing them in two we get the daily single-heading progress. The latest of the Alpine tunnels is the Loetschberg, now being driven. In this work the world's record has been beaten by a single day's record in one heading of 36 ft. and by an average daily record in. one heading of 29.5 feet. The Alpine range forms a natural barrier between a large section of northern and southern Europe. This range extends from the southeast of France to the frontier of Hungary, between Italy and the plains of southern Germany. The contour

Jul 1, 1911

Powder River Basin (PRB) mines were originally built to serve power plants designed specifically for their coal. Sulfur was the major concern, with BTU and sodium limiting the market for some. The Clean Air Act has extended the PRB market into plants converting from other coals. These new customers are more sensitive to constituents affecting boiler and precipitator performance. At the same time, the prospect of deregulation is forcing power companies to control cost more stringently than ever. Jacobs Ranch Mine has responded to the changing marketplace with an expanded coal quality and customer service program.

Jan 1, 1998

By Milton H. Fies

THE writer wishes to acknowledge at the outset his great sense of obligation to those who contributed so broadly and expertly to the preparation of this paper: Dr. Albert DeSmaele, Chairman of the Board of Directors of Socogaz, Belgium; Dr. Julien Venter, Director of the National Institute of Coal Mining and Coal Utilization Industry, Belgium; Dr. Roger Loison, Chief Engineer, French National Coal Research Board, France; and Dr. Erich Sarapuu of the Sinclair Coal Co., Kansas City, Missouri. Liberal use has been made in this paper of a recent publication on Russian, Italian, Belgian, and French experiments prepared jointly by the Centre d'Etudes et Recherches des Charbonnages de France (Cerchar) and the Institut National de l'Industrie Charbonnière of Belgium (Inichar).1 The writer is particularly indebted to Dr. E. T. Wilkins, of the Fuel Re¬search Station, London, and to Mr. James L. Elder, of the Alabama Under¬ground Gasification Experiment at Gorgas, Alabama, for their unfailing patience and effective support. Not only did these experienced and capable men edit and revise this discussion, but much of its content is a direct con¬tribution quoted in full from their memoranda. Without the assistance of all these colleagues, this presentation would not have been possible. It has been a privilege to serve and work with them and to acknowledge repeatedly their loyal cooperation. The recovery of the energy inherent in coal beds throughout the world has been done through the years by methods that today may be justly regarded as primitive. While the techniques of coal mining through the application of machines and the enhancement of information and skills have advanced to an extraordinary extent, particularly during the past 20 years, the underlying means is essentially the same as when man first began to mine coal. Despite this progress in the manner of coal mining, it continues today as a hazardous, toilsome, grimy task. Coal mining per se has advanced at a greater and more rapid stride in the past 25 years than the mining of any: other mineral, but the basic method is fundamentally the same as it was the first day a miner took a pick into his hands many centuries ago. This situation presents a challenge to mining engineers everywhere, from

Jan 1, 1953