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By Michele Ashby

The mining industry is facing new risks from peak commodities, the energy and economic crisis and stock market pressures. The Green Mining Industry Initiative is a risk management strategy for the future of the mining industry. Defining the Risks The bad news is peak commodities, energy and economic crisis and stock markets collapsing are the issues that are already hitting everyone?s bottom line and draining the treasuries of every mining company around the world. Higher energy costs are affecting the bottom line more than ever before, which is creating more risk for companies. Mining companies have major land positions around the world and they have major energy needs. Uncontrollable increases in energy costs, increased regulations for diesel fuel emissions and energy intermittencies are costing mining companies more time, money, and man-power, which are cutting into profits and hitting the balance sheet. The good news is, there are practical energy solutions which are off the grid, tried and true methods which can be implemented in a cost-effective manner and will increase profitability and save shareholder values as well as energy security for these companies and their projects. To date, most of the mining resource industry has not yet considered or used other forms of power like clean, sustainable, or alternative energy for their own energy needs. The reasons have primarily been pushback from the mining industry due to beliefs of older technologies in alternative energy, a lack of understanding of the cost advantages long term, and perceptions of environmental relativity.

Jan 1, 2008

By Kung-Lee Wang

This Bureau of Mines study illustrates the economic significance of the Florida phosphate industry to the State and to the Nation. Environmental considerations related to phosphate industry activity are discussed briefly. Based on forecasts of Florida phosphate production in 1975, and using 1972 dollars, regional and national output value, income, and employment created by the phosphate industry were estimated for 1975. State and Federal government tax revenues generated by the phosphate industry, are also measured. Further, the concentrated impact of the phosphate industry on certain Florida areas and on regional industries is examined. Finally, the phosphate industry's importance to the U.S. balance of payments, U.S. agricultural production, and the Frasch sulfur industry is considered, in addition to byproduct fluorine, and potential byproduct uranium from fertilizer manufacturing.

Jan 1, 1974

By B. Benmokrane, G. Ballivy

"RésuméLe mécanisme de transfert des charges et le processus de décohésion le long des scellements d'ancrages scelles dans des massifs rocheux sous des charges de tensionnement peut être examine par instrumentation de l'ancrage à l'aide de jauges de déformation. Dans ce contexte il est présente ici les résultats d'une étude, en vraie grandeur sur chantier, ayant porte, d'une part sur des essais d'arrachement conventionnels et d'autre part sur des essais déflagrée barres d'ancrages instrumentées et scellées à l'aide d'un coulis de ciment dans un massif rocheux sain et compètent. Les résultats décrits ici, particulièrement les profits de contraintes de cisaillement le long de l'ancrage, obtenus à partir des valeurs de déformations relevées sur les jauges, ont permis de préciser le niveau de chargement correspondant à la décohésion initiale du coulis de scellement, d 'examiner l'effet de la décohésion sur la distribution des contraintes et de caractériser le fluage du système barre d'ancrage/coulis de scellement.ABSTRACTThe load transfer mechanism and the debonding process along grouted rock anchor, subjected to tention loads, can be examined through the instrumentation of the anchor with the aid of strain gauges. In this context, the resultsof a full-scale site investigation including classical pull out tests and creep tests are presented in this paper. These tests were performed on instrumented bars which were cement grouted in a competent rock mass. Results presented in this paper concern, among others, shear stress pro/ties along the grouted anchors which were determined from strain values obtained from the strain gauges. These results have been used to: (1) predict the load level corresponding to initial debonding of the grout; (2) study the effect of debonding on shearstress distribution along the anchor; and (3) characterize the creep behavior of the bar anchor/cement grout system."

Jan 1, 1991

By H. P. Pew

THE Pembina oil field is in west-central Alberta, about 88 miles west-southwest of Edmonton. The field, about 35 miles long by T HE Pembina oil field is in west-central Alberta, about 88 miles west-southwest of Edmonton. The field, about 35 miles long by 85 miles wide, is the largest in Canada in areal extent, in the amount of oil in place and in the current producing rate. The discovery well was completed in the middle of 1953. The field has grown until its present area is 369,820 acres. There are 74 working interest owners in the field. Early in the producing history of the Pembina field a committee of operators was formed on a permanent basis. The Pembina Operators' Committee has established a permanent staff, which compiles and distributes pertinent field information on a regular basis to all participants. The Alberta Oil and Gas Conservation Board has dealt with field-wide problems primarily through this committee. Expansion of the field was rapid as shown by the number of wells completed -from 135

Jan 1, 1961

By Débora Guimarães da Silva

Este trabalho trata da deposição de um nanofilme de sílica através do processo sol-gel na superfície de um substrato vítreo para sua aplicação em usinas térmicas de energia solar. Os filmes foram confeccionados pelo processo de revestimento por imersão utilizando-se um equipamento dip-coating e passaram por um tratamento térmico à 425°C durante 30 minutos. Na etapa de caracterização foram feitos ensaios de espectroscopia de fluorescência de raios-X, refletância difusa no UV-Vis, microscopia eletrônica de varredura e medidas de molhabilidade. As propriedades mecânicas foram avaliadas por teste de adesão da fita e dureza a lápis. Resultados dos ensaios de espectroscopia de fluorescência de raios-X confirmaram haver a deposição de sílica sobre o substrato. Foi obtida uma refletância difusa de 2,72% para o filme antirreflexivo. Imagens no MEV revelaram uma superfície lisa, uniforme e isenta de trincas. Medidas de molhabilidade mostraram que houve o molhamento dos filmes pela água, caracterizando-os como hidrofílicos. Os filmes apresentaram uma adesão de 4B e dureza de 3H. Os nanofilmes de sílica confeccionados apresentaram propriedades ópticas e mecânicas satisfatórias para a aplicação solar.

Aug 17, 2017

By Joan K. Kuenzi

This Information Circular brings together for consideration recommendations from U.S. Bureau of Mines research in the area of surface mine mobile equipment maintenance for the period 1982 through 1991. It updates the 1982 contract report by Baker and Alves that formed the basis for much of the work described in the present report. Recommendations for hazard abatement during work on mobile one equipment are presented and stem from the results and recommendations of the research in two areas: (1) equipment and workplace hazard reduction, and (2) management of maintenance information. Recommendations included in this report apply to both the operators and maintainers of mobile mining equipment as well as to the manufacturers of that equipment.

Jan 1, 1995

By William E. Young

There are many large rhodunite-bearing veins containing manganese in the Eureka-Animas Forks area of the San Juan Mountains in Colorado. The Sunnyside vein is the largest known vein in the area. As observed on the surface, the vein is mineralized over 8,000 feet and attains a maximum width of 200 feet. The average width of the vein and its branches and ramifications is 58 feet in the area that was mapped in detail. The weighted-average analysis of surface and underground samples from the northeastern extension of the Sunnyside vein is 8 percent manganese. Most other known veins in the area have a similar manganese content. The Hidden Treasure vein lies southeast of the Sunnyside-No Name-Mastadon vein. The weighted average of the analyses of surface and underground samples from this vein is 13 percent manganese. Exposures of the Scotia-Silver Chord vein are visible over a strike length of 4,000 feet on Treasure Mountain. Diamond-drill holes show that the vein contains 10 percent or more manganese to a depth of 400 feet. The vein has an average width of 28 feet. The Independence vein is exposed on the surface for a distance of 600 feet and has an average width of 6 feet. Three cut samples taken across the vein had an average content of 20.7 percent manganese. Sampling of the outcrops of eight veins in the Placer Gulch area also indicates manganese. Numerous other veins cropping out in the surrounding area are similar to the outcrop of the. Sunnyside vein system mineralogically and are worth investigating.

Jan 1, 1966

By Donald H. McLaughlin

ZEST in the search for new supplies of metallic ores and petroleum is difficult to maintain with stocks of raw materials accumulating and with over- production rightly or wrongly blamed for most of our industrial troubles. Enthusiasm over new methods of prospecting has consequently diminished and exploration programs in many fields have been drastically cur- tailed. Very naturally the effects have been felt with particular keeness in highly specialized phases of the work, such as geophysical prospecting, for the feverish scramble for new areas in which to drill beneath magnetic or electrical anomalies has abated, and there is even a lull in the firing in the battle over salt domes on the Gulf Coast. It is unquestionably an unhappy time for many of the organizations dependent on this work, but in certain respects the situation may be beneficial in correcting unsound practices that .have grown up through the necessity for haste and for quick decisions. With the restriction of the field to the more competent workers by the harsh rule of survival of the fittest, a general improvement, not only in technique but in business methods, can be expected which may go far in restoring public confidence. Geophysical prospecting in the short period that it has been utilized in North America, has suffered severely both from over-popularity and from excessive abuse. The former evil now

Jan 1, 1931

By Lloyd Williams, R. E. Hershey, B. W. Gandrud

"1. The investigation shows that the Sewanee bed is the only bed of major importance in Marion County, 97 percent of the coal mined in the county having come :from this bed. There are coal reserves in minor quantity in the Battle Creek bed, and production from this bed depends on a few small truck mines. The Richland bed, or Lower Sevanee has been mined in the past, but no coal has been produced from it in late years. There are no production records of any other beds in the county, although some coal has been produced from them.2. Known measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and on l,800 tons per acre-foot of coal in place, are estimated to be 61 million short tons as of January 1, 1953. Of this total, 55 million short tons is in beds 28 inches and more thick. Areas in each bed ·were omitted from the estimate where available data relative to the bed characteristics are too meager to permit making an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves.3. Recoverable reserves of coal are estimated in beds 28 inches and more 'thick. This recovery is based on total thickness of coal in the bed (less partings 3/8-inch thick or more), rather than on the thickness of the coal actually mined. This thickness is about the minimum now being mined by hand loading onto conveyors in the Appalachian Region. The combined weighted average recovery for the Sewanee and Battle Creek beds in Marion County, as determined by this investigation, is 60.9 percent. Based on this, the recoverable reserves of coal in Marion County are estimated at 34 million tons."

Oct 1, 1955

By T. W. Martin

In 1973 the percentage of total coal production mined by surface methods in the United States again increased, reflecting a long term trend. Barely three decades ago less than 10 percent of the U.S. coal was produced in this manner. Last year surface coal mines produced 299 million tons, 50.7 percent of our nation's coal. At present there are about 2450 strip mines producing coal in 23 states. While accident rates for surface coal mines are less than underground coal mining rates, surface coal mining is certainly one of the more hazardous occupations. Figure 1 shows the injury rates (fatal and non-fatal accidents) of major U.S. industries. Note that surface coal mining is more hazardous than all other industries except contract construction. Accident rates are about the same as the contract construction industry which uses similar equipment. A limited amount of detailed data was available on elements of surface coal mining jobs and this lack of compiled information made it difficult to assess the significance of the conditions contributing to accidents and to make recommendations that would reduce accident frequency. Therefore as part of the Bureau of Mines continuing research efforts related to the health and safety of the coal miner, a contract was awarded to Theodore Barry and Associates of Los Angeles to conduct an "Industrial Engineering Study of Hazards Associated with Surface Coal Mines."

Jan 1, 1974

By T Raynlyn, R J. Holmes, J R. Manuel, A Poliakov, L Lu

The prediction of sintering performance of iron ore fines and the possibility of targeted optimisation of specific sinter properties are very important for both the iron ore industry and related research organisations. Physical pilot-scale sinter runs require large amounts of raw materials and are expensive, so it is critical to target large test work programs with many different sintering parameters effectively. To predict values for sintering performance parameters such as tumble index (TI), low temperature reduction disintegration index (RDI) and productivity, a comprehensive database of pilot-scale sintering experimental results has been established and empirical modeling conducted. Similarly to earlier work, physical, chemical and mineralogical characteristics of the iron ores have been considered. However, in contrast to the previous work where only one textural parameter was taken into account, namely the proportion of dense haematite ore texture, the current model includes the abundances of several different textures which were combined into different textural factors corresponding to different sinter properties. Coefficients for the variables within specific regression equations can provide a better understanding of the effect of the variables on the corresponding sintering performance. The modelling results have also been used for predicting the sintering performance of mixtures that were not part of the database used for establishing the models. Comparison of experimental and modeling results for the verification test data is also reported in this paper.

Jan 1, 2009

By Will B. Jamison

The most serious safety problems encountered in U. S. underground coal mines today are related to the roof bolting operation. Also, roof bolting is usually the operation which limits coal production of the section. The purpose of my paper is to review some of the research, developments, and new ideas related to roof bolting. Many of these ideas have originated at. coal mines or with manufacturers. Most of the research on fundamental improvements has been funded by, and is a part of, the excellent and broad plans of the Bureau of Mines.

Jan 1, 1977

By P. A. Riveros, R. Molnar, F. J. Baša

"An acidification circuit was installed and operated at the Agnico-Eagle Silver Division refinery in Cobalt, Ontario, for treating ~300 m3 of a concentrated cyanide waste solution with the purpose of recovering its cyanide and metal values. The acidification circuit was designed from parameters determined experimentally at CANMET. Available refinery equipment was assembled according to a flowsheet developed by Agnico-Eagle Mines. The process produced a regenerated cyanide solution containing >15 g/L of free cyanide, which was used for leaching gold ore at another Agnico- Eagle operation. It was estimated that the value of the recovered cyanide offset the treatment cost. BackgroundThe Silver Division of Agnico-Eagle Mines needed an economic and effective method for disposing of ~300 m3 of a concentrated cyanide waste solution that had remained in the plant after the operation was shut down in 1989. As a result of extensive recycling and evaporation, the solution had become practically saturated with metals, cyanide, thiocyanate, sulphate and other components, and was, therefore, an environmental liability for the company. A partial analysis of the solution is presented in Table 1. Initially, the use of cyanide destruction methods was considered by Agnico-Eagle, but the estimates indicated a considerable cost with no credits to be gained. A research project carried out by CANMET showed that a simple procedure consisting of acidification, filtration and reneutralization was the most attractive option, because it enabled the recovery of a substantial portion of the cyanide. Furthermore, the metals would be recovered in the form of a solid precipitate. The research showed that conventional AVR was not applicable because of excessive cyanide degradation and low HCN volatilization obtained with this particular solution (Riveros et al., 1996). This paper describes the procedure used to treat the concentrated cyanide waste solution and the operating practices of the large-scale acidification circuit run at the Agnico-Eagle refinery."

Jan 1, 1998

By N. G. Azeredo

This work dealt with the evaluation of engineering structural clay brick samples that were sintered at estimated temperatures of 700 and 800°C. They were collected in a red-brick plant in Campos dos Goytacazes, RJ, Brazil. From a lot, a sample already sintered in its kiln at 700°C were collected and also a sample from the same lot only dried by the air, which were then sintered at 800°C controlled temperature. The samples were subjected to Brazilian Standard tests (ABNT NBR 15270:2005) to determine their geometric, physical and mechanical properties. In order to be classified as structural clay brick it is required minimum 3.0 MPa for the characteristic compressive strength (fbk) to be suitable for up to five floors structural building applications. We also used the Weibull Probability Plot and Weibull Maximum Likelihood Estimation to evaluate distribution parameters in order to compare the results of compressive strength obtained in the tests.

Jan 1, 2015

In October 2005 Phelps Dodge mining, a US based company, visited several Australian mining companies and mine sites to ascertain the current applications of risk management methods in the organisation. The results of this review, documented by the author, indicated a ælayeredÆ approach from high level site or major hazard analysis through to face level, æstop and lookÆ, methods. The approaches of several companies were summarised in one simple layered model. This model is helpful to other sites and companies to identify potential improvements but also offers an image of best practice that may assist with the governance of OH&S by both company boards and community regulators. The issue is particularly relevant as we discuss national consistency in mining regulation. This paper examines the layered model, the company and site approaches that helped define the model, as well as the suggested implications of the layered model to governance.

Jan 1, 2006

By Aditya Rana, A. K. Mishra, M. M. Singh, N. K. Bhagat

Many cases of derailments, train accidents and traffic interruptions due to the slope failure and rockfall have been reported in the past on Konkan Railway trackline because of unstable rock slopes. The authorities installed stability enhancement measures such as wire netting, rock bolting and shotcreting which were found insufficient. The failed geotechnical measures prompted authorities to excavate the unstable slopes. Rock blasting is generally not preferred for the excavation of slopes along the transportation route. Stabilisation and widening of slopes by blasting need closure of the route for a considerable time. Discontinuing traffic on Konkan Railway route was undesirable as it connects two important port cities Mumbai and Mangalore. The paper presents an innovative directional controlled blasting (DCB) technique for excavating three unstable slopes (i.e. cuttings) in hilly terrain without disturbing the traffic. New empirical formulae for small geometry blasting to estimate burden and throw have been developed. A unique sequence of firing and excavation with powder factor varying between 0.04 and 0.39 kg/m3 irrespective of the actual free face was used for rock blasting. The process controlled the throw of blasted material over the track and resulted in a smooth and stable wall. The slope angle has been changed from 80 to 82° to 45–47° and probability of wedge, planar and toppling failures was eliminated. About 100 such accident-prone slopes (52 km cumulative length, 7% of total route) situated at discrete locations along Konkan Railway route were stabilised using the technique. No incident of rockfall and slope failures along these slopes has been observed after the stabilisation.

By Leslie D. Marrus

This project and final report represent an effort to collect, analyze, and verify reliability and performance data on currently available medium -to-high seam models of continuous miners being used in underground coal mining. The analysis determined availability, mean time and tons between failures, amounts of down time associated with various failures, labor and part costs required to correct failures, and various indices of maintainability. Machine performance and reliability are discussed relative to cumulative tons (machine age) produced and production rates (machine loading). It was determined that performance can be significantly improved given preventive maintenance programs that will increase machine availability.

Jan 1, 1976

By H. Gerry Stephenson, Devin Castendyk

"One of the most important environmental issues associated with contemporary openpit mining is the closure of mine pit lakes, and the perpetual legacy these lakes can potentially generate. Ideally, successful pit lake closure includes the following:• The water quality within the pit lake, plus surface water and ground water discharging from the pit lake, meets premining or other acceptable water quality conditions of the receiving environment. • The termination of all active treatment processes.• The return of the pit lake to the government for long-term care and maintenance.• The release of the mining company from all future liabilities associated with the pit lake.• The return of the environmental bond to the mining company.• The reuse of the pit lake for some post-closure, beneficial purpose.The achievement of these goals is known as walk away pit lake closure.Peer-reviewed publications of successful walk away, pit lake closure provide mining companies with the ability to address public concerns regarding the safety of pit lakes which commonly occur during the permitting, operations, and closure phases of mining. To date, most published work on walk away, pit lake closure work has occurred in the coal mining sector in Germany and Australia (McCullough et al., 2009; Jones and McCullough, 2011; Kumar et al., 2013; Schultz et al., 2013). In North America, examples of walk away, pit lake closure are not widely discussed in the literature despite there being excellent examples from the coal mining sector in Alberta, Canada (e.g. Pleasure Island, Black Diamond, East Pit, Sphynx, Robb, Lovette, Siltstone and Sterling), and from the iron mining sector in Minnesota in the United States (e.g. Portsmouth Lake, see MNDNR, 2018). Although seldom included in discussions of pit lakes from the metal and coal mining sectors, the aggregate and fabricated-stone mining sectors also produce pit lakes, and there are numerous examples throughout North America where these pit lakes have been successfully closed and transformed into post-mining resources (Vandenberg, 2018; Crossman, 2019). The difficulty of finding these good examples in the literature makes it challenging for companies to respond to public and regulatory questions regarding pit lake closure and reuse. As such, there is a pressing need to document the motivations and approaches used in examples of successful, walk away, pit lake closure in North America so that the mining industry, at large, can learn from these examples and can better address public concerns."

Aug 1, 2019

By AIME AIME

HE State of Utah has an area of 84,990 sq. mi., and like other inland states in the West its population, although steadily increasing, is relatively small. The fact that it is a state possessing vast mineral resources is attested by a careful study of statistics which have been compiled by Federal and State investigators. Some idea of the extent of these resources and the degree of development of a particular state or region may be gained by such a study, but in the case of Utah statistics and other available information fail to portray completely the true extent and value of its existing metallic and non-metallic resources. The State is probably more widely known for its production of metallic ores which has placed it in an eminent position among the metal mining states of the Nation.

Jan 1, 1925

By Oliver Bowles

WAR necessities have spurred inventive genius in many fields. A grinding mill without any moving grinding parts stirs the imagination. Among the new and striking accomplishments in the heterogeneous group of nonmetallic industrial minerals is the use of an electric arc to speed up manyfold the difficult and delicate task of drilling a microscopic hole in a diamond, the hardest of all known substances. Outstanding in the field of optical research is the ability that man has developed to improve upon nature by making in the laboratory optical crystals many times larger than those usually found in rocky crevices. These are merely samples of numerous events and circumstances of noteworthy import, many of which are recorded in this review. Termination of the second World War in 1945 permits an appraisal of the effects of the conflict and the probable effects of the coming restoration of a peacetime economy on the nonmetallic mineral industries. Some industries were stimulated greatly by the war, notably mica, quartz crystal, graphite, spinning asbestos, potash, fluorspar, barite, and refractories. The large-tonnage industries connected with the building trades, however, were forced to curtail their activities, except where their products were needed for wartime construction. Their reconversion to peacetime production will not be difficult.

Jan 1, 1946