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This publication contains eight papers presented at a Bureau of Mines Technology Transfer Symposium in Charleston, W, on June 22, 1983, Five of the papers describe the results of Bureau-sponsored research on cabs and canopies for low-coal underground mining equipment. The other papers describe the efforts of three underground coal mining equipment manufacturers (FMC, Joy, and Lee-Norse) in the area of cab and canopy design.

Jan 1, 1985

By Joseph M. Kuchta

This Bureau of Mines manual is oriented to the technical needs of an investigation of fire or explosion accidents and includes various practical and theoretical information that is needed in analyzing accidents or evaluating conditions that might lead to an accident. It is applicable to accidents in the chemical, mining, transportation, and other fuel-related industries. Specific procedures for conducting an accident investigation are outlined, and various guidelines are given for developing the fire or explosion evidence. Ignitability, flammability, and physicochemical data are presented for over 500 combustible gases, liquids, and solids; empirical and theoretical expressions are also given for extrapolating the behavior of combustible-oxidant-diluent systems to various environmental conditions. In addition, various data pertinent to damage analysis are summarized to facilitate the task of the investigator in developing plausible accident scenarios.

Jan 1, 1985

By Boyd Wise

A jet pump injector was developed and successfully tested, thereby demonstrating the feasibility of a jet injector for introducing coarse coal into an operating slurry face haulage system: In Phase I a variety of injection concepts were evaluated, and the jet pump was identified as best, due to its simplicity, compactness and performance potential. In Phase IIA subscale jet pump injector tests were conducted, and a computer model of a jet pump injector was developed whose performance predictions correlated well with subscale test results. In Phase IIB various system configurations were defined for integrating a jet pump injector into a fully operational underground coarse slurry face haulage system, further highlighting the feasibility and practicality of such a system. In Phase III a full-scale mobile haulage vehicle embodying a jet pump injector and coal sizing equipment was detail designed into a practical vehicle with attractive performance characteristics. More importantly, fully operational full scale jet pump injector -and feeder/breaker subassemblies were tested and proven successful in their ability to down-size coal to 3" in all 3 dimensions and to consistantly provide slurry of 4217 weight concentration at 6.4 TPM throughput under a wide range of operating conditions including zero to maximum feed rate within 5 seconds.

Jan 1, 1985

The concept of "classification is expanded beyond the performance of the classifying equipment to include all aspects of the fines removal system of the grinding circuit. Design and operating parameters which affect fines removal are identified and discussed, and a quantitative index for circuit fines removal effectiveness is defined. This approach lends new interpretation to certain observed phenomena, and suggests useful guidelines for circuit design and operation.

Jan 1, 1985

By Robert S. Schechter

This report describes the development and application of PHASEQ/FLOW, a geochemical flow simulator capable of describing the dynamic changes in chemical composition of an aqueous solution during flow in a permeable medium. The solution components can react through intraaqueous reactions, redox, precipitation, or dissolution. The assumption of local thermodynamic equilibrium ensures maximum generality with respect to the number of species and components possible; however, the fluid flow itself is limited to one-dimension. The report describes several applications: generic batch equilibria, flowing equilibria, uranium roll-front deposition, and roll-front leaching.

Jan 1, 1985

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Jan 1, 1985

By David L. Veith

This Bureau of Mines bibliography of U.S. and Canadian literature pertaining to revegetating coal-mined lands contains 805 references published from 1977 to 1984. Each reference is evaluated by keywords, providing the reader with a means of rapidly sorting through the references to locate only those dealing with the coal mining region and subject of interest. All references are annotated. Other sources of information are given, including Office of Surface Mining (OSM) and State reclamation agencies and other published bibliographies.

Jan 1, 1985

By Branch of Editorial Services

"The Bureau of Mines was established in the public interest to conduct inquiries and scientific and technologic investigations concerning mining and the preparation, treatment, and utilization of mineral substances; to promote health and safety in the mineral industries; to conserve material resources and prevent their waste; to further economic development; to increase efficiency in the mining, metallurgical, quarrying, and other mineral industries; and to inquire into the economic conditions affecting those industries. The organic act of the Bureau, as amended by Congress and approved February 25, 1913, made it the province and duty of the Bureau of Mines to ""disseminate information concerning these subjects in such manner as will best carry out the purposes of this Act.""In accordance with this directive, the Bureau reports the findings of its research and investigations in its own series of publications and also in articles that appear in scientific, technical, and trade journals; in proceedings of conventions and seminars; in reference books; and in other non-Bureau publications. The number of these reports, the wide range of subjects they cover, and the variety of mediums in which they appear make the kind of list and index presented in this special publication both necessary and valuable. This issue of the Bureau of Mines List of Publications and Articles describes reports and articles published during the period January 1, 1980, to December 31, 1984. It supplements the 50-year list of Bureau publications issued from July 1, 1910, to January 1, 1960;1 the 50-year list of articles by Bureau authors published outside the Bureau from July 1, 1910, to January 1, 1960;2 the 5-year lists of publications and articles from January 1, 1960, to December 31, 1964,3 from January 1, 1965, to December 31, 1969,4 from January 1, 1970, to December 31, 1974,5 and from January 1, 1975, to December 31, 1979;6 and the annual lists of Bureau publications and articles from January 1 to December 31, 1980,7 from January 1 to December 31, 1981,8 from January 1 to December 31, 1982,9 and from January 1 to December 31, 1983. 10"

Jan 1, 1985

By Flavelle IV

A survey is made of changes in the technical status of a number of western world copper extraction and refining operations over the past 20 years. Specific developments in pyro- and hydro-metallurgy and refining practices are identified together with factors in the changing environment of the industry which has influenced their adoption. Nickel extraction and refining is similarly discussed.The replacement of traditional technology by more attractive alternatives has occurred in a considerable number of operations. The develop-ment and status of new continuous smelting processes, advances in hydrometallurgy and refining innovations which emerged during the 1960s and early 1970s is discussed. The varying experience in commercial acceptance of these new technologies is noted.Finally some possible future directions are canvassed for both operators and the research and development institutions.

Jan 1, 1985

By P. A. Cox

Guidelines are provided for the design of explosion-proof electrical enclosures that will meet MSHA certification requirements according to Part 18, Title 30, of the Code of Federal Regulations, and fulfill their intended service underground. The guide covers only those aspects of design which affect enclosure strength, ruggedness, endurance and flame path, i. e., the enclosure ability to properly contain an internal explosion. Internal static and explosion pressures, external impact and thermal heating load are treated as well as the proper selection of materials and welding procedures.

Jan 1, 1985

By J. Currie, J. McManus, R. Chenier

"Cominco Copper Division&apos;s Valley Mine is located in the Highland Valley of British Columbia, approximately 275 km by air northeast of Vancouver. The nearest towns are Logan Lake, located IS km to the east and Ashcroft, located about 50 km to the northwest.Preproduction stripping of rock and overburden at the Valley Mine&apos;s Lake Zone Pit began in mid-1982 following a decision to discontinue mining in the adjacent Jersey Pit. Equipment and mining methods were carried over from the Bethlehem Copper operations which, with Valley Copper Mines, were merged into Cominco in December 1982.Blasting practices, as carried over from the Bethlehem pits, were designed to provide the fine fragmentation required to meet production requirements using the Bethlehem crusher. However, after mining the first few benches of the Lake Zone Pit, it became apparent that overblasting at the pit limits was causing a number of bench failures, as well as contributing to an over-all reduction of the material strength of the rock mass forming the southwest wall of the pit.With present ultimate pit plans calling for the southwest wall to be as high as 300 m, Valley staff realized that potential slope stability problems should be dealt with as early as possible. This philosophy would enable experimentation on phase pit walls in order to attain the optimum slope angle on the ultimate pit wall.As part of an over-a ll slope stability program, a controlled blasting program was initiated at the Lake Zone Pit in March 1983. In this program, Valley engineering and production staff worked together with Golder Associates in establishing design criteria and evaluating the results. This program resulted in a marked improvement in the soundness of pit walls while maintaining the required degree of fragmentation."

Jan 1, 1985

By Pratt V

The economic, social and political environment of the mining and minerals industries is, as we all know, volatile and affected by constantly changing international forces. In addition, the outcome of negotiations with overseas customers is often uncertain for long periods, or even unfavourable. The industries and companies represented at this Conference are in an arena of high competition, risk taking and enormous capital outlay. They are industries which our overseas markets (rightly or wrongly) have criticised for industrial relations problems, unreliable production and uncertain deliveries. They are industries which have an urgent need to be cost effective and competitive at all levels of activity.A critical factor in the mining and metallurgy industries is, therefore, its human resources and its human resource management. It requires the full use of available talent, innovation, skills and qualifications within its workforce, and the appropriate management of these resources.

Jan 1, 1985

By Roger J. Goodman, Don Riva

"IntroductionCrows Nest Resources Limited (CNRL), a wholly-owned subsidiary of Shell Canada Resources Limited, is nearing completion of its first coal project, located in southeastern British Columbia. CNRL shipped over 700,000 tonnes of thermal coal to foreign markets in 1982. With the completion of the metallurgical coal plant in December, 1982, shipments of both thermal and metallurgical coal will increase substantially in 1983 and will approach the anticipated operating capacity of 3.0 million tonnes in 1985. The Line Creek Mine lies some 25 kilometres north of Sparwood in southeast British Columbia (Fig. 1). The open-pit mine is located on top of Line Creek Ridge, with coal being hauled 16 km to the thermal and metallurgical coal preparation plants, situated adjacent to the already existing Canadian Pacific Railway. Most of the coal is moved by 108 car unit trains by CP Rail to coal ports in Vancouver, where it is loaded onto vessels destined for overseas markets. Some smaller scale car load shipments are moved by rail to contiguous markets in the Pacific Northwest. History The southeastern British Columbia area, known as the East Kootenays, is steeped in a rich coal mining heritage, dating back to the latter part of the nineteenth century. Predecessors of Crows Nest Resources Limited were instrumental in developing the rich coal reserves in the area. In 1887, William Fernie, a pioneer-cum-prospector recognized the potential of coal deposits in the East Kootenays. Spurred by the relentless push west of the Canadian Pacific Railway through the Crows Nest Pass area, Fernie recognized that it was just a matter of time before the steam locomotives provided him with his required market. That time arrived in 1897 when Fernie helped to form the Crows Nest Pass Coal Company and coal mining commenced at Coal Creek, near his namesake town of Fernie. During its almost 70-year history, this company produced over 48 million tonnes of steam coal and 8 million tonnes of coking coal. In 1965, the Crows Nest Pass Coal Company was re-named Crows Nest Industries, to better reflect its expanded interests into forest products, and it is the latter company which Shell Canada Resources Limited acquired in 1978. The extensive coal resources of Shell, in both Alberta and British Columbia, were rationalized into one group with the birth of Crows Nest Resources Limited to manage and develop the coal holdings."

Jan 1, 1985

By I. A. Tinto

Labrador City is located in the southwestern portion of Newfoundland-Labrador, approximately 965 kilometers north-east of Montreal. The mine and beneficiation complex of the Iron Ore Company of Canada, known as the Carol Project, is situated 535 metres above sea level in a climatic region characterized by cold winters and short, cool summers. History The iron Ore Company of Canada commenced work in the area in 1949, however, it was not until 1958 that the decision was made to proceed with mining operations. The ore body consists of Specular Hematite (Fe203) and Magnetite (Fe304) with small quantities of Limonite and Geothite. The average grade of the ore bodies is 39% iron.

Jan 1, 1985

By W. A. Jankola, M. T. Martin

"The world&apos;s first zinc pressure leaching plant at Cominco&apos;s Trail operations started production in 1981. Sullivan zinc concentrate is leached at the rate of 190 tpd in a four-compartment autoclave at elevated temperatures and oxygen pressures to produce a zinc sulphate solution and elemental sulphur. Zinc extraction exceeds 98% and sulphide to elemental sulphur conversion exceeds 95%.The sulphur is recovered from the discharged slurry in the underflow of a hydrocyclone, and is upgraded as a flotation concentrate. The concentrate is dewatered, melted and filtered to produce a polished sulphur product of better than 99% purity. An alternative sulphur recovery process employs an unique sulphur separation method that recovers over 90% of the sulphur in the molten state. The remaining sulphur is recovered by flotation following flash discharge of the slurry. The product slurry containing the zinc sulphate solution and the iron-lead residue joins the existing roast-leach zinc plant for purification and zinc electrowinning.IntroductionIn 1981, Cominco Ltd. commissioned the world&apos;s first commercial zinc pressure leaching plant at their Trail operations in British Columbia. As part of a $700 million modernization and expansion program for lead and zinc started in 1977, the company installed the first o f two autoclave trains.Prior to pressure leaching, zinc production was closely tied to acid and fertilizer production. Sulphur dioxide produced from roasting the concentrates had to be converted to sulphuric acid. Thus, any expansion of zinc operations with the roast-leach technology would have required extensive modifications to the acid and fertilizer plants as well as to the roasters. Zinc pressure leaching, on the other hand, offered a one-step dissolution of zinc from the concentrates with high extraction, and production of elemental sulphur. The associated dust and sulphur dioxide generated in the roasting process are both eliminated from the working environment of the pressure leach facility. The flexibility allowed by producing elemental sulphur, and the opportunity to break the sulphuric acid link for about 25 per cent of the targeted 272,000 tonnes per year zinc production was very appealing. The process was successfully demonstrated at a pilot plant in 1977(1-6)."

Jan 1, 1985

By Theodore S. Jordan

The discovery of a major porphyry-type copper deposit on the Papago Indian Reservation in Pinal County, Arizona was announced by El Paso Natural Gas Company in 1968. The deposit, known as the Lakeshore Property, contained an estimated 470 million tons of sulfides and oxides averaging 0.75 percent copper. History and Geology of the area have been described by Harper and Reynolds (1969). El Paso subsequently&apos; entered into the agreement for joint development of the property with Hecla Mining Company, with Hecla as the operator. The ore body consisted of three types of mineralization: 1) Disseminated Oxide Ore, <1% Cu 2) Disseminated Sulfide Ore, <1% Cu 3) Tactite Ore, >1% Cu

Jan 1, 1985

By Kyle Wightman

INTRODUCTION CRA Limited is the largest mining group in Australia by value of sales and the second largest company in Australia in terms of share market capitalisation. In the past 25 years, CRA, its predecessors and affiliates have been involved in a number of mining and further processing developments in Australia and elsewhere. Many of these have been financed using project financing techniques. These include Comalco&apos;s development of the Weipa bauxite deposits in Northern Queensland in the late 1950&apos;s, the Hamersley iron ore developments in the Pilbara region of Western Australia in the mid 1960&apos;s, the Queensland Alumina Limited alumina refinery in Gladstone, Queensland, at about the same time, and the Bougainville copper project in 1969/70. In the past three years CRA has again utilised project financing techniques to fund its Tarong steaming coal project in Queensland, the Blair Athol steaming coal project also in that State and CRA&apos;s interest in the Argyle diamond project in the Kimberley region of Western Austrlia. PROJECT FINANCE DEFINED Nevitt Definition Nevitt&apos;s is the most frequently quoted definition - "A financing of a particular economic unit in which a lender is satisfied to look initially to the cash flows and earnings of the economic unit as the source of funds from which a loan will be repaid and to the assets of the economic unit as collateral for the loan." Risk and Balance Sheet Treatment It is important to focus in more detail on two aspects of project financing, risk and balance sheet treatment. The assessment of the various elements of risk in a project and the sharing of that risk between sponsors and lenders is the most critical feature. At one end of the spectrum is full absorption of risk by the sponsor(s). This can be described as "on risk" or "on credit" or "full recourse" to the sponsor(s) and is effectively a corporate financing. At the other end of the spectrum the lenders absorb the whole risk in a non-recourse financing which is "off risk" or "off credit" for the sponsor. The other aspect is the sponsor&apos;s balance sheet treatment. If the balance sheet of the economic unit undertaking the project and the financing need not be consolidated into the balance sheet of the sponsor (because ownership does not exceed 50%) then the financing may be described as off-¬balance sheet. If consolidation is required then the financing is described as on-balance sheet. Most project financings involve some recourse to the sponsor, i.e. they are limited recourse. Very few are non-recourse or off credit to the sponsor. Limited recourse financings may be on-balance sheet although many may also be off-balance sheet insofar as consolidation is concerned. However, sponsor support may very well be a contingent liability to the sponsor and require disclosure by way of note to the balance sheet should consolidation not be required. CORPORATE FINANCE CONTRASTED A financing which is on credit or full recourse to the sponsor, whether it is directly borrowed or guaranteed by that sponsor, is a corporate financing. Lenders will tend to base their credit assessment on a historical assessment of the sponsor&apos;s activities and its financial results rather than an assessment of the project or a detailed assessment of the future activities and prospects of the sponsor. PROJECT FINANCE - A BORROWER&apos;S PERCEPTION Although CRA could choose to arrange all finance on a corporate basis (except perhaps for the very largest projects or acquisitions), project financing techniques provide a number of specific advantages which CRA has noted and which should be carefully considered by a project sponsor. Advantages

Jan 1, 1985

By David M. Rempe

The purpose of this standard is to provide a method for testing of cushion materials that leads to uniform results when employed by various organizations and laboratories. The load-deflection characteristics measured using this method are intended to provide input data for analysis of pile driving, as in wave equation analysis of pile driving. It should be recognized, however, that there are several factors which may cause a difference in performance between the test samples under laboratory conditions and actual cushion materials under pile driving conditions. These factors include variations in material properties from sample to sample, compaction and/or deterioration of the materials with use, eccentric loading due to misalignment, confinement effects or the cushion container or inter layered materials, head buildup, rate of loading, etc. In order to obtain representative load-deflection characteristics, therefore, testing of cushion specimens which have been subjected to actual pile driving conditions is encouraged 1 such specimen should be tested at various stages of the useful life of the cushion. The users of the data are cautioned to determine if the particular wave equation program they are using requires either the secant or tangent definition of the stiffness and modulus of elasticity.

Dec 1, 1984

By R. C. Burtan

Long before recorded history, man began to dig into the earth&apos;s crust in a never ending search for useful materials. It is well known that more than half of the earth&apos;s crust is composed of silicon dioxide (SiO2), also known as silica. Silica and silica-containing material have a great many uses in modern society. This material, however, is potentially an extreme health hazard. Silicosis: Not a New Disease Centuries before the Christian Era, Hippocrates wrote of a lung disease common to those who mined in hard rock. He was obviously describing silicosis. It is also apparent from ancient writings that the Egyptians were aware of this malady. Dioscorides also wrote on this subject in the fifth century B.C. It is undoubtedly the oldest and best studied of the occupational lung diseases. Silicosis was certainly described by Agricola in his De Re Metallica published in 1556. Here he described lung disease among hard-rock miners. The original document was written in Latin and then translated in 1912 by Hoover and Hoover. One of these translators was Herbert L. Hoover, a former US president who once made his living as a mining engineer. More recently, there are numerous references in medical literature in the 19th and 20th centuries relating silica exposure to silicosis. There are specific references to mining in hard rock, as well as to sandblasting and a host of other industrial exposures. In 1919, Winslow described standards for measuring the efficiency of exhaust systems in polishing shops using sandblasting. These standards were equally applicable in the mining industry. As early as 1920, Winslow explored the efficiency of certain devices used to protect sand-blasters against the dust hazard. These devices were equally applicable in the hard-rock mining industry. The medical community recognized the silica health hazard in the early 1900s. Middleton described the illness in the British Medical Journal in 1929. He noted the danger to health at that time. D. Hunter mentions in his book, The Diseases of Occupations (1969), the monumental work of Merryweather in 1936, in which he surveyed the silicosis risk in Great Britain. He showed statistically that the average employment length of sandblasters who ultimately died of silicosis was 10.3 years, compared to 40.1 years for all fatal cases, irrespective of occupation. Sandblasting and hard-rock mining and drilling, obviously, are very hazardous occupations. Weil and Zisking of Tulane University wrote in 1975 that "it was known as early as 1935 that the course of silicosis is much more rapid in sandblasters than in miners or foundry workers. This can be explained by the fact that sandblasters are exposed to an almost pure siliceous dust containing high concentrations of respirable particles within the range of 1 to 3 micron size." Protecting the Worker The medical community recognized in the early 1900s the need for proper protective equipment for all of those who worked with siliceous materials. Middleton, writing in 1929, said: "The worker is then protected by a close fitting helmet with an air feed, much as in the case of an underwater diver. In spite of these precautions, cases of silicosis among sandblasters are being met with today. It is a matter for serious consideration whether a substitute, such as steel or iron grit, could not be used to replace the siliceous grit as the abrading material." C. E. A. Winslow, a professor of public health at Yale School of Medicine, and others wrote of the need to protect sandblasters by

Jan 7, 1984

By J. E. Moyle

Introduction In October 1983, Rio Algom Ltd. decided to develop the East Kemptville tin deposit. This decision was the result of intensive geological and metallurgical evaluation work, as well as careful studies of environmental and marketing aspects. The property is located about 54 km (34 miles) northeast of Yarmouth, Nova Scotia, near the village of East Kemptville. Geology The geological setting is a granitic intrusive at the contact with metasediment. The tin mineralization is in the form of cassiterite (SnO2), which is about 80% tin. Sulfides are associated with the deposit containing silver, copper, and zinc, which are recoverable as byproducts. The mineralization is associated with quartz veins and greisen alteration. In the center of the deposit, the zones are so close together they have the appearance of a massive or porphyry type deposit. Ore Reserves The mine plan is based on 56 Mt (62 million st) at 0.165% tin. Up to the ninth year, mill feed will average about 0.2% and lower grade material will be stockpiled. In later years, the average grade will be 0.16% tin. A 0.08% cutoff grade is planned for the entire 17 years of production. East Kemptville is a relatively low grade tin deposit, and only a combination of favorable circumstances has made it economic. • The ore body is situated at, or very close to the surface, permitting mining by open-pit methods at a very low stripping ratio. • The tin occurs in relatively large crystals that allow for good recovery by gravity techniques. • It is ideally located in a well-settled area, with all essential infrastructural requirements already in place. • The positive and cooperative response from various governmental agencies involved are encouraging. Mine Plan The mine plan incorporates an initial pit, followed by three expansions to the ultimate pit. Mining will be at 14 kt/d (15,000 stpd) and will include 9 kt (10,000 st) of ore plus 5 kt (5,500 st) of waste and low grade. After five years, the mining rate will increase to 21 kt/d (27,500 stpd). It is planned to drill vertical 165-mm (6.5-in.) blast holes on a 6-x 6-m (20- x 20-ft) pattern. Bulk slurry explosives will be used to break the rock. Loading will be with hydraulic shovels into 70 t (77 st) haulage trucks. The trucks will deliver the ore to a 13 x 20 m (42 x 65 ft) gyratory crusher, where it will be crushed to 150 mm (6 in.). Secondary and tertiary cone crushers will be used to further crush the ore to 13 mm (0.5 in.). Process Design Tin extraction technology is practically unknown in North America, but Rio Tinto Zinc, which has a 53% ownership in Rio Algom, is involved in tin production in the UK. Rio Algom has used this experience and expertise in metallurgical evaluation work and in tin-related aspects of plant design. Mineralogical and metallurgical test work have been performed, both on laboratory and pilot plant scales. Mineralogical work was done largely in the UK, the laboratory test program was carried out at the Lakefield research facility in Ontario, and pilot plant work was conducted in Australia. This program has resulted in significant improvements in recovery and concentrate grades, over best projections that could be made before this work was carried out. Concentrating Process The concentrator is being designed to process about 9 kt/d (10,000 stpd). The first step is to reduce the size of the ore to -700 µm (-24 mesh) in a rod mill/ball mill grinding circuit. The ball mill will operate in closed circuit with high capacity banana-type screens. The screened product will be deslimed to 30 µm (560 mesh) with cyclones, then passed over the pri-

Jan 4, 1984