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By R. L. Kidd, T. H. Miller

"INTRODUCTION This paper is the seventh of a series of yearly reviews started in 1921 and pre¬sents information gathered in a cooperative investigation undertaken by the United States Bureau of Mines and the University of Utah. It is the purpose of this report to make available flotation—reagent consumption data and other milling information in such a manner as to be of value to the milling industry and to the manufacturer of flotation reagents.These data have been compiled from a survey of about 300 concentration plants in the United States. Much additional information has been obtained from the various offices of the United States Bureau of Mines. Many of the plants covered in the survey made complete reports of their operations, but others were apparently unable to supply this information in sufficient detail to meet the requirements of this report. As a result, some sections of the report are more complete than others. In general, however, the mill reports were much more complete than in previous years, and for the first time it has been possible to calculate average mill recoveries in the treatment of certain classes of ores. As in the past, every effort has been made to conceal individual plant operations.ACKNOWLEDGMENTSIt is realized that the publication of this information is possible only through the assistance of the mill operators, and the authors wish to express their appreciation of this cooperation. Thanks are also due the various field offices of the United States Bureau of Mines, division of mineral statistics, for assistance in collecting this information."

Aug 1, 1931

By G. L. Bloomsburg

This report describes work which was done to apply an existing finite element computer program UNSAT2 to the unsteady, unsaturated flow of water through waste shale piles. The work was done in three phases: 1. Verification of program through comparison with existing data. 2. Verification of program through simulation of flow from field seepage ponds at Rifle, Colorado. Considerable laboratory work was done in this phase to obtain capillary pressure-saturation-relative permeability data and hydraulic conductivity values for retorted shale. 3. Application of program to flow due to natural rainfall in a section through the Piceance Basin in Colorado, and a typical waste shale pile.

Jan 1, 1978

A methodology has been developed and demonstrated to be effective in reclaiming surface-mined land for a forestry post-mining land use. The Forestry Reclamation Approach (FRA) has been applied, almost exclusively, to flat or gently rolling surfaces. One of the primary steps in the FRA is to loosely grade the top 1.22-m (4-ft) of soil or substitute root growth medium to avoid excessive compaction. Concern has been expressed by regulators and the public that loose grading on steep slopes could lead to slope failures, which is one of the issues that SMCRA sought to correct. A field investigation was conducted at a steep-slope contour operation in eastern Kentucky to test the applicability of FRA in this setting. Final grading was performed according to FRA standards. The surface consisted of two distinct substitute rooting media. One was unweathered gray sandstone and the other was a combination of gray sandstone, brown sandstone, and topsoil. A variety of native hardwoods was planted following the FRA guidelines. The slope was instrumented with 70 survey monuments to monitor for mass movement. The reclaimed spoil was also characterized using bulk density and penetrometer resistance methods. The characteristics of both spoils are similar to those observed on flat to rolling surfaces where the FRA has been used and, after one year, approximately 70% of the trees had survived. There has been no major mass movement of the slope and slope stability analyses indicate that the application of the FRA has little impact on the overall stability of the slope.

Jan 1, 2011

The reconstruction of the world after the present war must inevitably be profoundly influenced by the rise and progress of New China.The principle of Chinese mathrity has been admitted by Great Britain and the United States by their abjuration of extra-territorial tights, and by the withdrawal of the Maritime Customs Administration. The United States admits equality by her declaration that Chinese are eligible for American citizenship, and the reaction to this will be swift enmity to such peoples as may impose humiliating restrictions upon Chinese citizens.Finally, the decisions of the Moscow Conference and the recent meeting of National leaders in Cairo give partnership rights to this new State in post-war reconstruction, and open the way for a rapid realization of her destiny.It seems certain that China, if so she wills, can become, within a generation or so, one of the considerable forces of the world. The toad she wiII follow will be lighted by her own inherent and intrinsic genius. Her speed of progress can no longer be forcibly influenced by other nations and the attitude towards her of somewhat contemptuous patronage hitherto adopted by the European communities bordering the Pacific Ocean must be radically modified.It is doubtful whether the European will ever reach full understanding of Chinese mentality. The Chinese "way of life" since the dawn of her civilization has been totally divergent from that of the European, but the enormous potential strength, due to the simplicity of their requirements and their steadfast industry, is a function of that "way of life." On the other hand the trend of reorganization must obviously be towards Western standards; and a wide knowledge of the potential strength of the Chinese is possible and will be essential in our post-war world. The following, necessarily inadequate, notes are therefore offered, as an indication of the obstacles to be overcome and the capacity of the Chinese executives and operatives to overcome them.For 'thirteen centuries the political and social structure of China proper (ie, excluding Mongolia, Manchuria and Tibet) has been rigidly shaped by the philosophy of Lao Tze and the ethics' of Confucius. This Taoism, which is described as the "way of harmony" with its three jewels of character, gentleness, economy and humility, advocates the minimum of social, economic and political organization and still gives the key to the Chinese character.The Mongol and Manchu conquests of the 12th and 17th centuries, respectively, could hardly be dignified with the name of war, but the superior intelligence and harder mentality of the unwarlike Chinese finally absorbed...

Jan 1, 1944

By R. Schuhmann

Jan 1, 1965

By Christian Roche

Our study is focused on the sub-assembly con-tact shoes, pressure rings and pressure bellows. We were keen to mainly study [ ] 1.The contact shoe design 2.The most efficient pressure to ensure an optimal electrical contact between the contact pad itself and the casing 3. The contact shoe cooling circuit in view to provide to the shoe the best mechanical and electrical characteristics in order to bring to the users of COFOR® components a new standard in process setting technical solutions. A finite elements simulation, combined with a thermal and structural studies were used. Our presentation which follows is dedicated exclusively on the influence of the contact shoe cooling system on the process through a thermal and structural analysis. [ ]

Jan 1, 2007

By A D. Price, W J. Germs, O Patterson, T R. Weaver

"Understanding controls on groundwater and surface water flow and quality at mine sites throughout all mine stages is critical to effectively manage environmental impacts over the entire mine life. Monitoring forms is an essential component of this proof of understanding. Typically, monitoring programs at mine sites have been developed in the framework of existing conditions. However; recognition of the challenges of climate change and the performance of mines during recent extreme events in Australia has highlighted the need to develop monitoring programs that are resilient and responsive to changing environmental conditions. Water monitoring programs need to be effective under a range of environmental conditions, potentially not historically experienced.This emerging challenge requires cross-disciplinary teams to work together to understand issues including: representativeness of background conditions to longer-term conditions at the mine site sensitivity of mine and closure designs to changing climate and hydrologic conditions methods of performance (eg water quality or quantity) failure during extreme climate events such as flood or extended drought.These understandings come together in a detailed conceptual and, in many cases, numerical hydrologic model that considers the mine-water environment under a range of conditions. The groundwater, surface water and water quality monitoring programs that are developed from the conceptual model need to be sufficiently responsive to be effective in the face of such changing conditions, with results in turn informing the conceptual model. Extended drought, major floods and changing weather patterns can alter recharge and discharge areas, oxidation profiles and ultimately, the contaminant flux estimates that would have contributed to mine design parameters and performance. Unless these effects are considered in the spatial and temporal design of the monitoring program and within the parameters monitored, the resultant program may fail to capture data that are critical to evaluating environmental impacts from mine sites.Developing and implementing a water monitoring program that considers these issues can build confidence in mine performance under a range of conditions, leading to increased confidence by all stakeholders in long-term mine performance during and after closure.CITATION:Weaver, T R, Price, A D, Patterson, O and Germs, W J, 2013. Developing resilient water monitoring programs in changing climate conditions, in Proceedings Water in Mining 2013, pp 109-114 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 26, 2013

By Alexander Nikolic

The paper presents the foundation design and construction of a landmark urban redevelopment scheme in central London, UK. The scheme comprises the new Tottenham Court Road Underground station, Crossrail interchange box and associated over-site commercial development. The paper focuses on the design, procurement and construction of large diameter bored piles, up to 68m in depth, which form the foundation support system for the over-site commercial development at Denmark Place. The congestion below ground required an intricate foundation design solution which has been a catalyst for developing innovative load transfer arrangements and has resulted in the advancement of pile construction technology in the UK. The foundation system was also designed to cater for the construction of two significant elements of proposed below ground infrastructure. Selected large diameter piles have been constructed within 1.1m of live underground railway tunnels. An innovative D-shaped pile was constructed in a zone subject to particular spatial constraints. The proposed Crossrail tunnels will be bored within 1m of selected over-site development piles. In addition, a 30m deep excavation forming a new escalator box will be constructed in direct contact with the over-site development piles. The stakeholder engagement process is described together with the foundation design development and buildability assessment. The benefits from early collaboration between the designers and specialist contractors are highlighted. From an analytical design perspective, the entire foundation construction sequence was modelled in detail in order to assess the soil structure interaction and any potential adverse effects on existing elements of underground infrastructure. The results from the three dimensional numerical modelling simulation are compared with field monitoring data.

Jan 1, 2011

Magnetic anomalies in the Southern Coalfields have been subdivided into two characteristic types. Each type is attributed to a separate cause, one being basement structure, and the other near-surface igneous intrusions.Detailed geological mapping of the area and the ability to sample throughout the coalmines greatly assisted in this subdivision.The Triassic sequence contributes no magnetic effect of its own except to diminish the effect of sources within the underlying formations by raising the level of observation.Detecting the presence of igneous intrusions ahead of colliery working faces by magnetic observations within the coal mines may be of value in preventing accidents caused by gas outbursts and in planning the workings so as to avoid loss of production time.

Jan 1, 1967

By S. Felderhof, W. S. Vaughan

"Over the years, it has been increasingly difficult for the minerals industry to raise the necessary capital for its activities. To alleviate this phenomenon, complete transparency and capital market efficiency is needed. Since a company’s mineral resources and mineral reserves base is an essential component to obtaining capital, reporting these assets must also be transparent and efficient. This must occur, however, at an international level given that mineral industry operations, and its financing, are international. To achieve this, an international committee (i.e. Australia, Canada, South Africa, the United Kingdom and Europe, and the United States) was formed and has been developing standards for the reporting of mineral resources and mineral reserves.The effectiveness of these standards, however, depends on adoption by the required regulators. Unfortunately, these standards have not been recognized by the U.S. Securities and Exchange Commission (SEC). Instead, the SEC adheres to its old standard (Industry Guide 7), making it increasingly expensive and difficult for international mining companies to obtain capital in the United States. Compounding the problem is the SEC’s influence over the current work of the International Accounting Standards Board and the International Organization Organization of Securities Commissions. These organizations are in the process of standardizing international accounting practices and international securities rules and regulations. Their current position may prevent adoption of the industry-developed mineral resources and mineral reserves standards which are internationally recognized."

Jan 1, 2005

By S. Mafi

The Broken Aro project is associated with a 1910 abandoned underground mine complex that has been discharging aeid mine drainage from entries, seeps and springs. The Ohio Department of Natural Resources(ODNR), R&F Coal Company (R&F) and American Electric Power (AEP) are involved with this unique project that will remine the abandoned underground complex and install a mine seal constructed of fixated flue gas desulfurization (FGD) material. The goal of the project is to eliminate or reduce the acid mine drainage that is discharging into the watershed. This paper discusses remining, installation of the FGD mine seal, government financed reclamation projects and future application to active and abandoned mining sites.

Jan 1, 1998

By Ian Misich

Surface subsidence resulting from "total extraction" of coal in the Collie Basin first occured in 1987 when Western Collieries Ltd trialed the Wongawilli mining method. Because very little quantitative subsidence data existed for the weak, Permian sediments, a research program was set up prior to the extraction of the first panel. The objective of the study was to be able to predict subsidence characteristics and effects prior to mining future total extraction panels. Attempts at predicting subsidence began using existing subsidence models from other coal mining regions, however, as more site information became available, it became clear that it was necessary to develop a separate, site specific predictive model for the Collie Coal Basin. Analysis of extensive field monitoring data for both surface and subsurface subsidence has produced a series of empirical models which can predict the shape of surface subsidence troughs and corresponding tills, and strains for rectangular panels and describe the sequences of ground movement from the mine root through to the ground surface. The fact that both subsurface and surface subsidence characteristics have tied in well, gives greater confidence for predictions made from these models

Jan 1, 1992

By N. E. Hanna

The current list of permissible explosives includes 124 different brands. Fifteen of these are gelatinous, and the rest are the more commonly used granular ammonium nitrate type. Their rates of detonation range from 1,300 to 5,600 meters per second, and the weights of 1-1/4 x 8-inch cartridges range from 86 to 244 grams. The list of permissible blasting devices includes 1 Cobra, 2 Hydrox, and 9 Cardox models. All of these devices are based on discharge of high-pressure gas from a pressurized shell in a shothole. INTRODUCTION To be approved for use in underground coal mines in the United States, explosives and blasting devices must pass certain schedule tests prescribed by the Bureau of Mines. The explosives listed here were tested under Schedule 1-G,3 which has since been replaced by Schedule 1-H;4 the blasting devices were tested under Schedule 26A.5

Jan 1, 1962

By Mary Ann Bennett, Val Nichols, Colleen Proctor

"In 1997 when Royal Oak Mines Inc. went into receivership, the mineral processing technicians (mill operators) who had been working at Giant Mine in Yellowknife, Northwest Territories for most of their career walked out with no credentials to serve as testimony of their knowledge and skills.As a result of new diamond mining activity and the establishment of socio-economic agreements, mining industry representatives approached the Department of Education, Culture and Employment (ECE), Government of the Northwest Territories, in 1999. They requested support and direction to promote training and recognition for mineral processing technicians at BHP’s (BHP Diamonds Inc.) Ekati mine. ECE recommended the development of occupational standards and certification.This paper describes the development process and end products that resulted from this collaborative project between industry, government and education. In addition, industry representatives involved in the project share their views on the development process and the benefits of standards and certification.The conclusion invites industry members to support national occupational standards and certification with their associated benefits: standardized training in the workplace and institutions, proof of competence for hiring, recognition of prior learning, and a nationally and internationally recognized credential.INTRODUCTIONSwiftly changing labour market demands are nothing new in the North. The fur trade and mineral discoveries have brought employment to workers in a feast and famine cycle for decades. In the late 1990s, the Giant, Con, Lupin, Polaris and Nanasivik mines were nearing the end of productive runs. Many experienced workers found that without credentials, they had no proof of their abilities to offer prospective employers."

Jan 1, 2005

The commonly used Stopes-Heerlen coal petrographic classification and nomenclature has over the years been subject to variable interpretations. This paper discusses the problem with specific reference to the inertinite maceral group. The effect of various interpretations of the Stopes-Heerlen system on maceral analysis is discussed and illustrated by means of comparative analyses conducted by a number of laboratories in Australia.An attempt is made to define the reflectance thresholds used by the authors to subdivide the inertinite group; the genetic and technological significance of these thresholds are compared.The difficulties of distinguishing structured and nonstructured macerals of the inertinite group are discussed in terms of possible improvements to the present StopesHeerlen system by extending the classification to include transitional maceral types.

Jan 1, 1970

The Government signalled its intention in the Economic Statement on 17 December 1987 to improve the fairness of the taxation system and to facilitate the process of economic adjustment by: removing tax concessions that benefit some taxpayers at the expense of other taxpayers,ensuring that those who can afford it shoulder their fair share of the tax burden,securing a revenue base which will provide sufficient resources to maintain effective social services,reducing artificial protection and concessions that discriminate against some sectors, and encouraging confidence through an economic environment with a medium-term orientation. The Government has clearly stated to all sectors that tax preferences will be phased out and businesses need to look inwardly to their investment policies if they are to survive in an open economy. This paper will address the effect of these Government objectives on the taxation structure for all forms of mineral exploration in New Zealand. The present tax structure will firstly be analysed, in particular setting out the tax advantages available to the industry. The effect of changes to the tax system within the recent past which relate to mineral exploration will then be examined. Finally the paper will address the question of possible future changes, particularly in the light of Government's intention to move towards a tax system which does not provide an advantage for any one sector of the economy.

Jan 1, 1988

By Ilija Ilic

Recovery of tin from tinplate and production of good-quality detinned-plate for further processing in ironworks has been the subject of interest for many years. Tinplates are mostly used for production of tin containers for food industry and consumer goods. The research carried out so far included determination of the parameters of dissolution of tin from tinplates by alkaline solution of NaOH and electrochemical recovery of tin from the alkaline solutions. During leaching, NaNO3 and methanitrobenzoic acid (MNBA) as oxidants were studied. By leaching the waste tinplate which contains 0.31 % of tin with a solution of 1.12 mol/dm3 NaOH, 0.26 mol/dm3 Na2CO3 and 0.09 mol/dm3 MNBA at temperature of 70°C for 60 mm, a degree of tin leaching of 97 % was attained. MNBA facilitates oxidation of Sn2+ into Sn4+ suitable for obtaining compact, and not spongy, Sn cathode deposit, as it was the ease earlier. Recovery of tin by electrolysis from solutions obtained by leaching was studied to determine the effect of electrolyte composition on the quality of cathode deposit and the degree of electric current efficiency. Experimental results obtained at a laboratory level were checked on an enlarged laboratory set up where continuos leaching of tin from waste tinplate and its electrolytic recovery from the solution obtained were carried out. The experimental set-up -operated under semi-industrial conditions, and about 500 kg of waste tinplate was processed yielding about 1.160 kg of tin (99 % Sn).

Jan 1, 2000

Sixteen papers concerned with the technology and utilization of low-rank fossil fuels are presented as the proceedings of the 1973 lignite symposium. This symposium, the seventh in a series of biennial meetings, was cosponsored by the Bureau of Mines and the University of North Dakota.

Jan 1, 1974

By Pierre L. Labelle

Non electric Dual Delay initiators have revolutionized many aspects of underground mining. The units are used in all types of underground blasting operations. Some operations, due to the complexity and variety of their blasts, have extremely large inventories of conventional non electric products. The Dual Delay system has drastically reduced these inventories and has added an important element of versatility to blast designs.

Jan 1, 1994

The Bulli Seam, New South Wales, comprises medium to low volatile bituminous coal, generally of coking quality. It is worked over an area embracing 300 square miles.Variations in several factors are found.1. The seam is somewhat disturbed and dissected by various structural features.2. This structure, and present topography, have resulted in depths of cover from very shallow to approaching 2,000 ft in the presently worked areas.3. Wide variations of seam thickness occur.4. Gradations of rank occur from place to place.5. Variations in seam gas content and wide variations in seam gas composition are experienced.6. Variations in coal strength occur.These factors may contribute to the occurrence of stress and gas phenomena in mining exploitation.INTRODUCTIONThe Bulli Seam, the most extensively worked seam in Australia, is the uppermost seam of the Illawarra Coal Measures, which comprise the southern portion of the Sydney Coal Basin. Generally, the rank of the seam and its assemblage of types make it ideal for the production of hard metallurgical coke. The thickness and relatively flat dips render the seam suited to mechanized bord and pillar mining, and this method is used almost without exception. At the north-eastern corner of the field, stress and gas phenomena have occurred during mining.Various data have been assembled on physical, chemical and geological conditions of the seam which may influence the occurrence of stress and gas phenomena. This material is presented in an attempt to explain the location of such phenomena to date, and to enable variations in conditions to be considered when future possibilities are being assessed.

Jan 1, 1963