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By Staff

"INTRODUCTION Sheet mica is one of the most important minerals in modern industry. It is used in many kinds of electrical devices, and up to the present time no satisfactory substitute for it has been developed. It is necessary for the successful operation of airplanes, ships, motor vehicles radios, and radar equipment. Early in World y r II, the Array and Navy, foreseeing the need for conserving the stock of sheet mica on hand and realizing that imports from India and Brazil were falling off, had strategic mica placed on the critical war-materials list.Examination and exploration by the Bureau of nines indicated that there probably are large undeveloped deposits of mica in Alabama, some of which are near the surface and others at greater depth. The quality of most of this mica is high.During World War I, Alabama mica producers added materially to domestic production, but after 1920 virtually all of the mines closed end miners scattered. During World War II, when imports from India, Madagascar,Brazil,,other foreign sources were reduced, sometime was required for Alabama to act into production. Operators began to produce small quantities in 1942.The Colonial Mica Corporation was created by the Government during 1942 to buy Mica for the Metals Reserve Company, end later Colonial was made sole buying accent for strategic mica. About this time the Bureau of Mines estab¬lished the graphite field laboratory at Ashland, Ala. Samples of mica wore submitted for examination, and advice was requested by property owners and mine operators. This continued during 1943, when as many as 400 visitors a month called at the Bureau's Ashland field laboratory."

Aug 1, 1946

By C. E. White

History The Con-Rycon mine is situated in the Yellowknife mining district, North West Territories, 608 air miles north of Edmonton, Alberta. The earliest reported discovery of gold in the area was made in 1898 but no extensive exploration occurred until 1928. The birth of Yellowknife as a mining community took place in 1934 with the staking of the Rich group and subsequent shipping of 16 tons of high grade ore. The Giant group was also among the claims staked in 1934, and later staking showed a tendency to close the gap between these two properties. In the fall of 1935, the A.Y.E. claims, situated south of the Giant group, were staked to cover a discovery of the Geological Survey of Canada and, after general release of the Survey's information, the adjoining ground was staked. These claims included the Con, Negus, Meg, and Kam groups. In 1936 four lapsed claims were re-staked as the P and G group and later acquired by Rycon Mines, Limited, controlled by the Consolidated Mining and Smelting Company of Canada, Limited. The Con and various adjacent groups owned by Cominco are now operated with the Rycon under one management. Surface trenching on the Con property started in 1936 and, during the fall and winter of 1936-37, a 60- foot 5 ft. by 9 ft. inclined prospect shaft was sunk. The encouragement provided by the shaft and diamond drilling in 1937 led to the decision to establish a mining plant, and in August, 1938, the 100-ton cyanide mill produced its first brick- the first gold brick poured in the history of the North West Territories. In November, 1938, the mill was enlarged to a 175-ton capacity and operated at this rate until 1941, when refractory ore was encountered. This situation was met by the installation of flotation and roasting units and, at the same time, the milling capacity was increased to 300 tons daily. Labour shortages and Government restrictions forced a reduction of output and in 1943 milling was suspended while mine development continued on a reduced scale throughout the war years. The present full-scale of operations was resumed in 1946 and the total production to the end of 1948 amounted to 288,853 oz. gold and 72,347 oz. silver.

Jan 1, 1949

By Kenneth L. Driggs

The Environmental Protection Agency's Clean Air Act of .1970 provided the driving force for the current Magma Smelter configuration. The historical and technical perspectives of those process developments are reviewed. Innovations in procedures and equipment have allowed compliance with the requirements of the regulating authorities. The wet scrubbing of converter gasses and the monitoring of converter operations by a controlling foreman are two of the major contributors to these successes. The Clean Air Act Amendments of 1990 have posed many new concerns for all U.S. industry, including the few (seven) primary copper smelters remaining. Future concerns include tightening the sulfur dioxide ambient standard from the current three-hour averaging period to one hour"

Jan 1, 1992

By W. E. Pittman

The Bureau of Mines, as part of its Health and Safety Technology Program, is conducting research on the use of ground penetrating radar (GPR) for mine hazard detection. GPR offers a possibility of mapping immediate below-surface geologic conditions, including faulting and other anomalies, thereby exposing potential safety hazards to miners. This report summarizes a literature review of the current status of GPR research in and outside the Bureau.

Jan 1, 1984

By Henning Schwarz, Ade Ogunsola, Anas Almousa

"The Riyadh Metro, commissioned by Arriyadh Development Authority “ADA” - the executive arm of The High Commission for the Development of Arriyadh -, forms part of a new public transport-system of Saudi Arabia’s fast growing capital city. The Design & Build project consists of 176 km of Metro Line with 57 km of tunnels. Beyond the Design and Construction, an additional aim of the ADA is to introduce up-to-date methodologies and improve safety in construction projects. A systematic dilapidation survey of buildings and infrastructures was a prerequisite for designing the required instrumentation and monitoring tools. Site investigations required of existing methodologies and the use of geophysical methods for achieving reliable results. Large diameter TBM tunneling is challenging in hot weather conditions and karstic ground. The present paper shows how modern technologies for underground construction are introduced into the local industry and gives an outlook on future projects in the Kingdom of Saudi Arabia. INTRODUCTION Riyadh, the capital city of the Kingdom of Saudi Arabia, is a fast growing city with more than 5.7 million inhabitants. The growth of the city is linked to the recent history of the Kingdom, where some initial milestones from the 1950’s can be highlighted: Revenue generation from the exportation of oil from the Kingdom; downstream investment of oil revenue in the reconstruction and development of the Kingdom; a general plan for the settlement of the Bedouins; the provision of a public electricity network for the city; the opening of the Riyadh - Dammam railway corridor providing a link from the capital to the Eastern Region; the commissioning of Riyadh airport (converted to Riyadh airbase, after the opening of King Khalid International Airport in 1983); and the relocation of ministries and other central government agencies in 1955. In 1974, The High Commission for the Development of Arriyadh was established as the organizational, planning, executive and coordinating body responsible for the development of Riyadh. Arriyadh Development Authority “ADA”, established in 1983 is the High Commission’s executive, technical and administrative arm. The ADA is responsible for implementing the High Commission's organizational, planning, executive and coordinating decisions and missions. The ADA’s president is a member of the High Commission (ADA 2015). One of the remits of the ADA is the preparation and execution of a transport plan for the city of Riyadh."

Jan 1, 2016

By Joseph Grumer

The range of composition of gases synthesized from solid fuels which are exchangeable with natural gas on current gas appliances was evaluated by theoretical principles. These principles consider primarily the flashback, blowoff, and yellow-tipping characteristics of air-entraining burner flames. It was found that complete identity between the synthetic and natural product is not necessary. Gases such as may be obtained by hydrogasification of coal and other solid fuels without the removal of unreacted hydrogen offer advantages in flame characteristics. Between 25 to 37 percent hydrogen can be tolerated in the sendout gas.

Jan 1, 1965

By E. C. Roper

THE Britannia Mining & Smelting Company, Limited, have been operating their property at Britannia Beach, B.C., continuously for nearly forty years and have mined over 33,000,000 tons of ore from orebodies within a belt of highly sheared rocks, five miles long by 2,000 feet wide. The property is in the Coast Range mountains, about twenty miles due north of Vancouver. The mountains rise abruptly from sea level to elevations of 4, 500 feet within a horizontal distance of 7,000 feet. The topography has enabled the orebodies to be developed by adit tunnels. The active mining levels are connected to the adits by incline and vertical service shafts. The main service adits are the 2200, 2700, and 4100 levels (see Figure 1). The mine surface shops, three bunk-houses, and over one hundred dwellings form the townsite camp at the portal of the 2200 level adit. A small camp of one bunk-house and a few dwellings is situated at the 2700 level portal. The beach surface shops and camp, adjacent to the 4100 level adit, service the mill, foundry, and other beach installations as well as the mining from the 4100 level. The ore mined from the various orebodies is delivered to the 4100 main haulage level through a system of rock raises and intermediate tramming levels and is hauled on the 4100 level to the mill.

Jan 1, 1945

By Evan Just

?We are certain there is need for research in every phase of mining." This statement by R. M. Crump of the Jones and Laughlin Steel Company (047) paraphrases opinion widespread among mining people. It is undoubtedly true. In preparation for this presentation, 193 organizations were asked to describe their mining research efforts. 60% responded, The meaning of "research" was taken in several different ways. The continual efforts of progressive companies to improve themselves were reported as research. We will call this and any effort to solve specific and immediate problems "practical research". The continuing investigation of subjects of long range interest will be called "basic research".

Jan 1, 1961

By Christopher C. Jobes

This U.S. Bureau of Mines report describes a system to determine the position and heading of a mining machine during maneuvers in the face area of an operating mine section. The system is the first step in the development of a guidance system for automated mining machines. The position and heading algorithm is described, and a preliminary error analysis is performed. The sensors employed were linear position transducers mounted on a mining machine with their cables attached to points on a stationary reference. Four linear position transducers were used to provide a data redundancy that increased the reliability of the guidance system. The linear position information obtained from the transducers was processed mathematically via the position and heading algorithm to provide the desired position and heading information. The algorithm takes advantage of sensor redundancy to continually test the accuracy of the sensor data. The major sources of error were determined to be the linear position transducers, the analog-to-digital (A/D) converter used to interpret the data, and the sampling frequency of the measurement system. These sources of error were evaluated to determine their inaccuracies for use in calculating the overall system accuracy.

Jan 1, 1990

By Francois Mignard

With a limited global steel production growth, automotive application market shows interesting volumes and trends especially in emerging countries. The recent period has again enabled Siemens VAI to confirm a position amongst leading suppliers of new plants serving high-end steel production in particular for unexposed and exposed automotive material. With a series of recent plant references in operation and under construction, relevant answers to such sustained level of performances are highlighted along the downstream processes. Designed for a wide range of applications, Siemens VAI processing lines includes advanced technological and state-of–the art equipment, among them, Solid state laser welder, Pickling Tunnel tanks, Skin pass mill and Tension leveller, Side trimmer with dynamic width adjustment, and new generation of Automatic surface inspection systems. With a continuous aim of driving improvements, Siemens VAI has also developed Global Quality Monitoring solutions notably through advanced software which provide just-in-time warnings and assist steel makers in the daily operation of their lines. As lifecycle partner, Siemens VAI offers solutions and services in metallurgical expertise from metallurgical modelling, through physical simulation on rolling, annealing and galvanizing processes, and enables Siemens to accompany our customers along with their project definition till fulfilment of highest market requirements.

Jul 30, 2018

By Jeffrey Y. Foley

Chromite deposits along the Border Ranges Fault in southern Alaska were investigated by the Bureau of Mines. This report, part 1 of a two- part series, describes the deposits. Part 2 describes the mineralogy and the results of metallurgical tests. Fieldwork began in 1981 and continued through 1983. Ninety-four subeconomic podifom chromite deposits in eight mafic-ultramafic complexes were investigated. Previously unreported chromite deposits at Red Mountain on Kenai Peninsula, on Kodiak Island, and near Tonsina are described. Deposits range in size from less than a thousand tons to over 1.25 million tons of contained chromic oxide (Cr203). Grades range from about 5 to 10 pct chromite. Excluding all deposits more than 10 miles from tidewater or existing roads and all deposits containing only chemical- or refractory-grade chromite, about 2,200,000 tons of Cr203 are contained in 41 hard-rock deposits. A placer deposit contains an additional 556,000 tons. These 42 deposits constitute a subeconomic indicated and inferred reserve sufficient to meet the Nation's chromite demands for about 4 yr, or the metallurgical industry's demands for over 5 yr, at 1981 consumption rates.

Jan 1, 1985

By R McIlwraith, B Breul

Two case studies are presented in this paper. The first one discusses a roller compacted concrete water supply dam that was constructed in El Mauro in Chile to provide water for agriculture activities downstream of a copper mine during the dry season. The 23 m high dam used a bituminous geomembrane (BGM) as the low permeability upstream facing element on the dam to control seepage through the dam. This is the first time that a BGM has been used in this application. A deep cut-off trench was used to control seepage beneath the dam and through the abutments. This paper briefly presents the design of the dam, including selection of the concrete mix and maximum aggregate size that the use of the Coletanche BGM allowed, and provides details of the construction, quality control and assurance of the installation of the BGM. An ultrasonic apparatus was used as part of the quality control on the BGM seams.The second case study discusses a tailings dam in Cerro Lindo, Peru (near Chincha), where a watertight BGM was installed on the upstream face. Results are presented of the survey done by a consultant on the behaviour of the dam and in particular of the BGM following an earthquake of magnitude 8.1 in Chincha close to the site. These findings on-site were checked by trials in a laboratory in California. Test results are given and explained.CITATION:Breul, B and McIlwraith, R, 2015. Case histories – roller compacted concrete dam waterproofing with a bituminous geomembrane in Chile and a tailings dam in Peru subject to an earthquake of 8.1 magnitude, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 367–372 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

Risk management has taken on renewed vigor since the economic crisis of the late 2000s. The resources of governments, individuals, and corporations are being stretched to a point where only the most promising projects move forward. Risk management is a crucial part of the decision making process, yet it remains a broad term that includes disciplines from engineering to finance. A collaborative effort will be necessary to ensure that the most auspicious and appropriate projects are the ones moving forward. Risk management can be quantified to an extent by comparing the likelihood of an instance with the result of consequence of the instance occurring. In this manner it is possible to assign risk factors to instances and ultimately, begin to associate monetary value to the instance. Carbon sequestration is an emerging field that has a number of unique challenges. Risk management and mitigation must be an integral part of the overall picture. This begins with the planning and design phase, continues through implementation and production, site closure, and does not cease until termination of liability. The ability of carbon sequestration projects to successfully assess, mitigate, and recover from leaks will be a decisive characteristic of overall success. The costs of mitigation and failure will need to be analyzed on a test level, but will still need to be reliable enough to extrapolate to a commercial level operation. This paper will build a risk management profile based on case studies and field tests in Tennessee and Virginia. These tests are scheduled to commence in late 2013 and consist of small-scale injection tests in unconventional storage reservoirs with an emphasis on enhanced coalbed methane (ECBM) recovery and enhanced gas recovery. The ultimate goal will be to provide a clear and concise direction to move carbon sequestration from the test phase to commercial scale. While it is necessary from a risk management perspective to analyze all risk points, the scope of this paper will focus on pre-injection risk assessment for carbon dioxide (CO2) leakage potential. Despite the differences between the two tests, CBM compared to shale among other differences, a framework for analysis and mitigation can be developed pertaining to leakage risk. The probability of each type of failure will be assessed and analyzed, and plans to mitigate or reduce these risks will be reviewed.

Aug 1, 2013

By HAROLD VINTON COES

MANAGEMENT has been tersely defined as getting things done through the efforts of other people; but before we proceed further, let us distinguish between administration, management, and organization. Oliver Sheldon in his book, "The Philosophy of Management," offers the following definitions: Administration is the function in industry concerned in the determination of the corporate policy, the co-ordination of finance, production, and distribution, the settlement of the compass of the organization, and the ultimate control of the executive.

Jan 1, 1943

By Diana Drinkwater, Tim Napier-Munn

"This paper argues that, although specialist mineral engineering expertise is essential for the efficient design and operation of mineral processing plants, the environment in which these skills are supplied to the industry has changed forever, and not for the better. Most of the mineral engineering programmes in western universities have died or are dying. The long-service mine site mentors have gone, operations are run on a staffing shoestring so that there is no longer the time (or inclination) for considered decision-making, and the FIFO model has discouraged continuity of optimisation projects and communication between professionals. At the same time the technical challenges of designing and operating effective process plants are increasing. These trends are not going to be reversed any time soon, if ever. The ability to run efficient mineral processing operations has been materially compromised as a consequence. We propose that well-designed professional development can help to recover this situation, and it can be done easily and cheaply. The workplace is the best environment for such skills development. Professional development training should be integrated with normal duties throughout the early years of a graduate’s service (and probably beyond), and the cost should be regarded as non-discretionary expenditure for the business. If such programmes are properly resourced and managed and extended over longer time periods, there will be a measureable rise in the level of technical understanding and competence within companies and a resulting beneficial impact on resource utilisation and thus shareholder value. The paper outlines some of the approaches that we believe will work, and the benefits that we expect will accrue."

Jan 1, 2014

This report presents a Bureau of Mines study comparing the construction costs, leakage measurements, and predicted performance of different types of large stoppings built and tested in a room-and-pillar oil-shale mine. The six full-sized structures (30 ft high by 55 ft wide) included both permanent and temporary stoppings and were fabricated using materials ranging from structural steel to coated brattice cloth. Leakage across each stopping was measured at differential pressures ranging up to 1.0 in w.g., using both the brattice window method and sulfur hexa-fluoride (SF6) tracer gas. Blast air pressures resulting from a full-scale face blast of approximately 1,800 lb of ammonium nitrate-fuel oil (ANFO) explosives were measured across two of the stoppings and the pre-and post-leakage rates were compared for all the stoppings. Overall performance of the stoppings for production applications was evaluated using an operational model of a two-panel oil-shale mine. Different combinations of temporary and permanent stoppings were evaluated based upon ventilation performance and construction and operating costs.

Jan 1, 1988

By R N. Humphries

The aim of this paper is to question the need to develop bespoke monitoring and assessment methodologies and criteria, thereby ‘reinventing the wheel’, when designing and assessing the success of important natural habitat and ecosystem restoration schemes at mine sites in the UK and Australia. It draws attention to the existence and applicability of the Phase I Habitat, National Vegetation Classification (NVC) and Condition Monitoring methods in the UK and similar approaches used in Australia. These are long accepted established methodologies and have published accounts for describing, assessing and managing natural vegetation communities, habitats and ecosystems. They are often used at the environmental impact stage, but seemingly rarely, if at all, in restoration design and management at mine closure. Their application to mine restoration and closure is illustrated and discussed by reference to a surface coalmine in South Wales, UK.It is concluded that the application of a combination of the Phase I Habitat, NVC and Condition Monitoring methods is highly relevant to the expectations of the Convention on Biological Diversity (CBD) and its implementation in the UK, and probably in Australia too. The methodology and criteria described could be incorporated into the guidance and specified in the mining permits so that there is clarity as to the expectations and requirements for monitoring and assessment for bond release. Their use could be of wider application where there is a requirement to assess the success of restored CBD assets and ecosystems.CITATION:Humphries, R N, 2014. Why reinvent the wheel when there are established methodologies to aid the design and assessment of restored natural ecosystems on mined land?, in Proceedings Life-of-Mine 2014 , pp 675–692 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By Jurgen Weissflog

Why, where and since when using shiftable conveyors? Advantages of this equipment The ever increasing demand for bulk materials such as ore, coal, lignite, oilsand, oilshale and bauxite requires mainly an opencast operation. To exploit these materials huge amounts of overburden and partings must be transportes by means of conveyors, trucks or trains. When analyzing the various opencast mines it can be established that there exist only two basic types of mining systems, i. e., the discontinuous strip mining system as used in the USA (Fig. 1) and the continuous mining system as is commonly applied in Europe. The reason why these two mining methods have been developed parallel to and independently of each other to such a high technical standard results from the varying geological conditions of the mineral deposits.

Jan 1, 1983

By S. Peng, N. Vayenas, A. Farah

"While genetic algorithms have been widely adopted in ore grade estimation and optimization, mine design, and production scheduling in the mining engineering field, reliability and maintainability analysis of mining equipment using genetic algorithms has been a relatively new research area in recent years. This paper presents an application of genetic algorithms using case studies with seven underground scoop trams whose maintenance records have been collected over a period of 12 months from an underground mine in the Sudbury mining area. Based on the assumption that various factors that contribute to machine failures resemble the biological evolution process, the authors have developed an in-house PC software application called GenRel which adopts genetic algorithms in its programming. In this study, the authors feed the historical maintenance data into GenRel in order to predict future maintenance characteristics of mining equipment in a time period of three months. Then the predicted maintenance characteristics are compared to the actual maintenance records in the same time period. A statistical study is then used to examine the similarity between the predicted data and the recorded data.INTRODUCTION Today maintenance costs of sophisticated engineering systems are so high that maintainability draws great attention from scientific researchers to operations managers. For instance, a study by [1] shows that American manufacturers spend more than 300 billion U.S. dollars on plant maintenance and operations. Therefore it is understandable that the main objectives of applying maintainability principles to engineering systems are to reduce projected maintenance costs, to use maintainability data to estimate system or equipment availability/unavailability and to determine labor-hours and other related resources needed to perform the projected maintenance. A system with better maintainability would inherently provide the benefit of lower maintenance costs, less time to recover with lower breakdown frequency (design for simplicity), less complexity of maintenance tasks and relatively reduced man-hours [2]. Most maintainability functions use the Time To Repair (TTR) as the independent variable. It is common to use probabilistic or statistical concepts to define a maintainability function, for example, the probability density function. Let t denote the time. Assuming a repair starts at t=0 and completes at time T, the maintainability can be mathematically defined [3] as in Equation (1)."

Jan 1, 2015

By R. H. Nafziger

Owing to the growth of alloy steel production and its influence on tramp element levels when recycled, foundries have expressed concern regarding the quality of scrap used to prepare iron castings. Reliable and current information was unavailable on the amount of tramp elements contained in iron castings over time. Accordingly, the U.S. Bureau of Mines, in cooperation with the American Foundrymen's Society (AFS), analyzed cast iron samples from participating foundries throughout the United States on a quarterly basis to ascertain possible trends. Each sample was analyzed for 28 elements to determine if changes had occurred as a function of several input variables. This bulletin describes the research and presents analytical results and evaluations over a 5-3/4-year period from January 1981 to September 1986. Results show that iron casting compositions are changing with respect to a few tramp elements such as arsenic, cobalt, chromium, tin, and zinc over the period. Changes in charge compositions probably are responsible. Significant variations between zones also were observed with aluminum, arsenic, cobalt, chromium, copper, and manganese.

Jan 1, 1990