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By John C. Machisak

THIS INFORMATION CIRCULAR covers the calendar year 1055 and contains statistical data on employment and injuries pertinent to metal and nonmetal mining and to their mills and processing plants that are voluntarily reported annually to the Federal Bureau of Mmes. This report, unlike previous publications, lists not only production and development workers but also office employees associated with mining and milling or processing. The last publication m the series, Information Circular 7798, Injury Experience in the Metal and Nonmetal Industries, 1954, also contains unpublished injury and employment statistics for 1943 through 1953. The Bureau is authorized to request data on injuries and employment from operators in the metal- and nonmetal-mining industries. The information voluntarily submitted by these operators contributes immeasurably to the promotion of safety in the mineral mining industries as it discloses the hazards to which metal and nonmetal workers are continually exposed during mineral extractive operations.

Jan 1, 1959

MRS. SIDNEY J. JENNINGS, President MRS. ARTHUR S. DWIGHT, First Vice-President MRS. KARL EILERS, Second Vice-President MRS. H. W. HARDINGE, Third Vice-President MRS. BRADLEY STOUGHTON, Recording Secretary MRS. AXEL 0. IHLSENG, Corresponding Secretary MRS. HARRIS K. MASTERS, Treasurer Welfare Committee MRS. C. C, BURGER, Chairman Sub-Committees Americanization Belgian Relief MRS. LEVI HOLBROOK, Chairman MRS. HENRY H. KNOX, Chairman Emergency MRS. HERMAN A. PROSSER, Chairman A very successful meeting Of the Council of the Woman's Auxiliary was held Wednesday, July 18, and plans for war relief work were thoroughly discussed. The Belgian Relief Committee has sent out the following letter to the ten local sub-committees, which were formed to raise money to feed the Belgian children: "The Commission for Relief in Belgium announced in a letter from Mr. Hoover that after the first of June the United States Government would take over the relief of Belgium and Northern France and called attention to the following paragraph: ?Naturally, having built up such an effective organization you will desire to keep it alive as far as possible, and we venture to suggest that, although the general relief of the countries involved will now be met by the Government appropriations, emer-gencies and special conditions may arise which could only be met by private donations. In such circumstances your organization will afford a ready means of meeting the demands of the situation, whatever they may be. Should any of your contributors

Jan 9, 1917

By Ziyad Abunada, David O’Connor, Fei Jin, Abir Al-Tabbaa

"In-situ remediation of contaminated land with deep mixing can enable a multi-technique remedial strategy on the same site combining low permeability barriers, permeable reactive barriers, stabilisation/ solidification treatments as well as ground improvement, delivering significant advantages over alternative strategies. This was the core objective of Project SMiRT (Soil Mix Remediation Technology) which involved the execution of the largest research field trials in the UK to date to provide field validation for this technique. Around 800m3 of soil were treated on a contaminated site in Yorkshire in May 2011 with 6 different treatments, testing ~40 binder compositions and 10 different installation methodologies. Field monitoring, testing and coring activities at the site took place within the first 2 months after treatment and then again at 34 months after treatment. This paper presents an overview of the field activities to date and some 3-year results and assessment of a subset of the treated soil sections. Some good correlations are seen together with some clear differences between treatments. There is generally an observed consistency with depth, with the mixing effectiveness having a more profound effect than the binder composition or content, within the tested materials and ranges. These field trial activities are currently being used in the development of the full-scale commercial remedial strategy for the site.INTRODUCTION AND OVERVIEW OF PROJECT SMiRTWhile there are strong financial and environmental incentives to remediate and redevelop brownfield sites there are also barriers including fear of the unknown, regulatory control, delays, increased costs and the stigma associated with such sites. Hence the remediation process needs to be conducted in such a way to maximise the incentives and overcome the barriers, which is how deep mixing found its niche in the land remediation market. Soil mix technology is such a versatile technique that can perform a number of remediation treatments on the same site. These include low permeability in-ground barriers (cut-off walls), permeable reactive barriers (PRB), stabilisation/solidification (S/S) treatments, other additive related remediation, e.g. in-situ chemical oxidation and bioremediation, as well as soil amendments for greening and also ground improvement all on the same site (Al-Tabbaa et al, 2011). Placed in the context of alternative solutions, soil mix technology could potentially replace the five techniques shown in Figure 1, which would be required to deliver the same treatments mentioned above. Treatment trains strategy, where a combination of techniques in succession are used to both reduce the contamination levels and deal with residual contamination, is becoming common in land remediation and the use of one set of equipment to deliver this would bring about significant financial advantages. In addition, soil mix technology has many other advantages in terms of speed of implementation, elimination of exposure to contamination, elimination of off-site disposal and low cost. Soil mix technology for the remediation of contaminated land emerged in the UK in the mid 1980s and has since been employed in over 30 or so projects, which far exceeds its application to ground improvement for which only a handful of jobs have been carried out to date."

Jan 1, 2015

By André de Cabral Oliveira

With the onset of the global economic crisis in 2008, and more precisely from 2009, production routes in iron making as blast furnace, sinter and coke oven, indicated a significant increase in frequency as well as intensity of undesirable incidents. The cost impact of such deteriorations of the production chain cause significant losses ranging up to several hundred million dollars annually. On the other hand, opportunities for processes improvement are contributing to enhance process efficiency and results, and also reduce or even avoid losses from unexpected incidents. The use of specialized services for processes has gained projection along the plants and emerged as an attractive alternative to increase results by increasing the performance and reducing costs and expenses. Process Services are formatted to achieve cooperative and customized solution during planned or urgent interventions, conducting feasibility studies, process improvement, training, among others, providing knowledge, information and crucial actions to preserve and optimize processes and plant facilities.

Aug 2, 2018

By Ted H. Eyde

Both private industry and the Interior Department have become alarmed about the enormous amount of Federal land that has been withdrawn from appropriation either under the Mineral Leasing Laws or the Mining Law of 1872. According to a recent article by Gary Benethum and L. Courtland Lee, governmental actions have withdrawn nearly 400 million acres from the operation of the Mining Law of 1872 and over 500 million acres from the Leasing Laws. An addition al 100 million acres for the Mining Law of 1872 and 70 million acres for the Leasing Laws are either encumbered or being managed in such a way as to constitute a defacto withdrawal from mineral development. This means simply that mineral exploration end development under the Mining Law of 1872 is either prevented or discouraged in an area the size of the states of California, Arizona, Washington, Oregon, Nevada, Utah, Idaho, and one half of Colorado combined. Under the Mineral Leasing Laws, exploration and development is either prevented or discouraged in an area equal in size to all the states east the Mississippi River, except Maine.

Jan 1, 1976

By J. J. Bean

This paper, describing the milling practice at the oxide concentrator of the International Smelting Co., is one of a series on milling methods and costs being published by the United States Bureau of Mines. GENERAL DESCRIPTION The oxide concentrator is properly an integral part of the Tooele plant of the. International melting Co., located 5 miles from Tooele, Tooele County, Utah. It has a capacity of 300 tons of ore per day and uses an all-flotation process to treat custom siliceous oxidized lead ores obtained principally from the Tintic district in Utah. Ores found amenable to the process are purchased on a custom basis, the principal tonnages being obtained from the Tintic Standard and North Lily mines.

Jan 1, 1933

The Tom's Gully gold mine is located 90km ESE from Darwin, in the Northern Territory of Australia. The orebody is the auriferous portion of a large sulphide rich quartz reef, hosted in the Wildman Siltstone Formation of the Early Proterozoic Pine Creek Inlier, at the NH extremity of the Mount Bundey granite-syenite intrusion. It was discovered by Carpentaria Exploration Company Pty Ltd on November 17th, 1986, using stream sediment geochemistry.The reef is 800m long at surface, strikes E-H and dips approximately 300 to the south, becoming progressively less steep. Only the eastern half of the reef is auriferous, with gold grades averaging 9 g/t plus anomalous silver, base metals and arsenic.The enclosing siltstone is a dark grey banded carbonaceous and pyritic metapelite, showing areenschist regional metamorphism and thermal effects from the adjacent pluton. Local folding plunging gently SW is cut by a south dipping fault, probably a thrust, in which the reef was later formed at about the time of the granitic intrusion. The main sulphides in the reef are pyrite and arsenopyrite, with gold occurring as microscopic particles in...

Jan 1, 1990

By Charles Sabine

The U.S. Bureau of Mines studied mines and prospects in the Bristol/Granite Mountains Wilderness Study Area (WSA) in 1982. The 45,000 acre WSA, located in the eastern Mojave Desert of California, is underlain by Mesozoic plutonic rocks with scattered roof pendants of Paleozoic (?) metasedimentary rocks. Two mines and six prospects are identified; one mine, the Silver Lode Mine, and a prospect of unknown name are adjacent to the area. The Silver Lode Mine has occurrences of silver, lead and zinc. Within the study area, the Comanche Mine has occurrences of iron and copper and the Iron Victory Prospect has an occurrence of iron. None are large enough to constitute a resource. Occurrences of magnesian marble at the Comanche Mine, Iron Victory Prospect, and elsewhere in the area contain too much MgO for commercial use other than agricultural soil supplements or crushed stone. Transportation costs to markets would exceed the value of the rock. At the Comanche Mine, situated in a roof pendant of marble, about 10 tons remain of a 110-ton pod of magnetite which contained 42.5% iron, and less than 50 tons remain of a mineralized fault breccia which averaged 2.5% copper and 0.3 oz/ton silver. Magnesian marble contained 41 to 45% CaO and 14 to 16% MgO. Primary and secondary silver, lead, zinc, and copper minerals are disseminated along altered joints and in quartz veins in quartz monzonite at the Silver Lode Mine, adjacent to the WSA. Analytical data are sporadic; samples contained as much as 0.12 oz/ton gold, 1.8 oz/ton Silver, 1.1% lead, 3.8% zinc, and 0.3% copper. Mineralized zones in the workings are not resources, but they might indicate possible silver-lead-zinc resources at depth. At the Iron Victory Prospect, lenses of magnetite and hematite with some chalcopyrite occur in a skarn lone in a marble roof pendant. About 110,000 tons of iron-rich rock, averaging 47.2% iron, are present; the largest lens contains about 30,000 tons. About 150,000 tons of magnesian marble, averaging 41.0% CaO and 11.7% MgO, are also present. Deposits of stone, and sand and gravel in the WSA are too distant from markets to be resources. Occurrences of energy minerals were not identified.

Jan 1, 1984

By N. Som

The pile capacity in cohesive and granular soils depends on a number of parameters. The values of these parameters as recommended by Indian Standard Code of Practice vary over wide ranges. A designer often finds it difficult to select appropriate values of these parameters for realistic estimate of a pile capacity. The present paper makes a critical review of the values of the parameters given in Indian Standard Code of Practice and suggests a realistic approach to selecting them in the light of recent research.

Jan 1, 1996

By Olav Dalen

A HUNDRED years have passed since Wöhler made the first few particles of aluminum by decompos-ing aluminum chloride with potassium. In 1854 Deville used sodium to decompose the double chloride of aluminum and sodium, but even various subsequent improvements of the process, especially by Castner, did not sufficiently decrease the cost of the metal to bring it into general use. In 1862 Monckton proposed to reduce Al O? with carbon by the aid of the electric current, but the efforts of the Cowles brothers to do so were not successful and in 1884 they turned to making aluminum alloys by electrolysis. At about the same time Hall in America and Heroult in France success-fully worked out the technology of dissolving A12O3 in fused cryolite and electrolyzing the bath. It is hard to realize that forty years ago the annual production of aluminum was only 30 to 40 tons per year and the price of the metal thirty times what it is today. Great strides in decreasing the cost of production, improving the quality of the metal, and increasing the output have been made in the lifetime of middle-aged men. The large consumption of electrical energy in the form of direct current makes it necessary to locate aluminum-producing plants near waterfalls, to avoid transmission losses. Norway with its abundant water-falls is therefore a logical place for the development of aluminum production, even though it is necessary to import the bauxite, which is the raw material of the process. It was foreigners who first started the aluminum in-dustry of Norway and the first two plants were built by the British Aluminium Co. in 1906 to 1908; one at Vigeland near Kristiansand, and the other at Stavan-gerfjord in Nordfjord. These two plants are still oper-ating and producing over 3000 tons a year. When the plant at Vigeland is enlarged the production of the company will be more than 4000 tons a year.

Jan 11, 1927

By P. R. Dugan

The ultimate objectives and interest in removal of sulfur from high sulfur coal include: (a) reduction of the atmospheric load that con- tributes to the problem of acid precipitation; (b) reduction of ash which contributes to decreased energy transfer in boilers and the problem of ash disposal; and (c) alleviating the social and economic dislocations related to uneven geographical distribution of sulfur in coal reserves. The cost of sulfur removal in relation to the value of refined coal will govern the development of an emerging coal-refining industry. The value of refined lower sulfur coal will be influenced by the national commitment to the environment as well as economic considerations.

Jan 1, 1986

Edwin H. MessiteR, New Pork City (communication to the Secretary*):—Under the heading " Flues," Mr. Edwards refers to the Bee-hive construction, a cross-section of which is shown in Fig. 4 of his paper. A flue similar to this was designed by me about six years ago,' in which the walls though much thinner than those described by Mr. Edwards gave entire satisfaction. These walls, from 2.25 in. thick throughout in the smaller flues, to 3.25 in. in the larger, were built by plastering the cement mortar on expanded-metal lath without the use of any forms, or cribs, whatever, at a cost of labor generally less then $1 per sq. yd. of wall. Of course, where plasterers cannot be obtained on reasonable terms, the cement can be molded between wooden forms, though it is difficult to see how it can be done with an interior core only as stated by Mr. Edwards. In regard to the effect of sulphur dioxide and furnace-gases on the cement, I have found that, in certain cases, this is a matter which must be given very careful attention. Where there is sufficient heat to prevent the existence of condensed moisture inside of the flue, there is apparently no action whatever on the cement, but if the concrete is wet, it is rapidly affected by these gases. At points near the furnaces there is generally sufficient heat not only to prevent internal condensation of the aqueous vapor always present in the gases, but also to evaporate water from rain or snow falling on the outside of the flue. Further along, a point is reached where rain-water will percolate through minute cracks caused by expansion and contraction, and reach the interior, even though internal condensation does not occur there in dry weather. From this point to the end of the flue the roof must be coated on the outside with asphalt paint or other impervious material. In very long flues a point may be reached where moisture will condense on the inside of the malls in cold weather. From this point to

Jan 1, 1905

By H. R. O'Brien

"During the past year, the Pittsburgh experiment station of the Bureau of Mines has been investigating methods for the quantitative estimation of carbon monoxide in blood. This work was necessary because reliable methods of analysis are of the greatest importance in the bureau's research work on prevention and treatment of carbon monoxide poisoning among workers in mines and metallurgical plants. Two of the methods considered involve color comparisons. In one of these methods, differences in tint can be noted fairly readily, while in the other, they are much more difficult to detect. The latter, however, is otherwise considerably simpler. It was decided, therefore, in studying the possibilities of this second method, to use the most sensitive eyes in the laboratory force.Preliminary trials.The method under investigation was the Haldane carmine determination of carbon monoxide in blood. The plain oxyhamoglobin of the blood in dilute solution is a pale straw color, when exposed to carbon monoxide it becomes a cherry pink. In the analysis dilute indigo carmine is added to oxyhsmoglobin until the solution matches in tint the carbon monoxide hemoglobin. The eye wanted, then, was the one most sensitive to faint pinks. But just how to select the analyst was not clear At first the Williams test scale, used in the Navy, was considered, but on con¬sultation with Dr. L. L. Thurston, bead of the Department of Psychology at Carnegie Institute of Technology, the following procedure was adopted.Instead of standard tests made up of all colors, only those occurring in the analysis were used. Solutions were prepared of the two hemoglobins, from which twenty-four different pairs were made up and placed in test tubes like those expected to be used in the analysis. One of each pair differed from the other in percentage of carbon monoxide hemoglobin by amounts varying from 2-1/2 per cent to 20 per cent. Each pair was compared in a box built in our own shop. This was 20 inches long and 5 inches square in cross section. One end was covered with ground glass. Just inside this glass cover were provided two slots, each the width of the test tubes used. The tubes to be compared were dropped into these slots through two holes in the top of the box. The device was placed before a window away from the sun, and so arranged that the light conditions were the same on each slit or opening. The person to be tested was seated before the box, and as the two tubes were placed before him side by side, he marked whether A (left) or B (right) contained the more cherry pink. This procedure was continued till he had compared all the pairs."

Jul 1, 1921

By Daniel E. Sullivan

This Bureau of Mines publication examines the potential impact on minerals of the tariff and nontariff agreements that resulted from the Tokyo Round of the Multilateral Trade Negotiations, which were conducted under the auspices of the General Agreement on Tariffs and Trade. These agreements will affect minerals by reducing tariff levels and by changing rules by which they are traded internationally.

Jan 1, 1981

By Forrest T. Moyer

To keep the mineral and allied industries informed of trends in the causes of accidents, and to point out the need for corrective measures, the Bureau of Mines collects, analyzes, and periodically publishes health and safety statistics. This report includes data for 1963 on injury experience, with related employment statistics, at coal mines in the United States. These data are presented in tabular form under the following headings: General Injury Experience Tables 1 to 6: Current data on number of injuries, degree of injury, frequency and severity rates, average severity, and related employment and production data by work location.

Jan 1, 1966

By R. Reed von Gal

The majority of zinc strip produced in the world today is cast on the Hazelett twiri-belt continuous casting machine. Ten of these machines are currently operating worldwide, and one machine is under construction for the People's Republic of China. The caster, which was first patented in 1947, was originally developed for aluminum and copper alloy casting. In the early 1960s, the design was expanded into zinc casting and within ten years the industry had essentially converted from casting and rolling ingots to twin-belt continuous casting with in-line rolling. The casting process employs two parallel, moving. water-cooled belts as the major mold surfaces. Together with two strings of side dam blocks, the design offers a four-sided moving mold which produces a continuous strip or bar. This paper will cover a bit of, the history, as well as the current technology surrounding this high production process for zinc strip production.

Jan 1, 1990

By D. W. Tully

Sedimentary and volcanic rocks of the Timiskaming series trend west-ward across the property of the Upper Canada mine, forming part of the north limb of a regional syncline which is truncated on the south by the Larder Lake fault zone. A wide zone of schistosity strikes east-west through the sediments and volcanics. The central portion of this zone is occupied by a system of narrow gouge-filled fractures in highly altered rocks, mainly tuff, trachyte, trachyte porphyry and syenite porphyry. The alteration zones have developed through repeated stages of deformation and accompanying metamorphism. The initial stages were marked by carbonatization and sericitization, followed by silicification and the introduction of minor amounts of sulphide minerals. Gold was finally de-posited in relatively late fractures within silicified zones and pyrite. Repeated movements along the Up-per Canada break have offset post-ore dykes of minette and diabase, and have resulted in minor displacements within the orebodies.

Jan 1, 1963

By P. Personnet, D. Wheaton, E. Couzinie, V. Demetriou, Brooks. W., G. Girault, M. Meyer, L. Charbonnel

A common problem in Gas Treatment Centers (GTC) from primary aluminium smelters is the temperature of the gas to be treated : above a threshold, filtering media are irreversibly damaged. The traditional way of dealing with high gas temperature is to dilute with fresh air, which implies over sizing - and therefore higher cost for - the GTC in order to have the capacity to treat this dilution air without compromising on pot suction. A system was developed which decreases gas temperature without having to use dilution air. This system is based on water pulverization in gas collectors. The water vaporization leads to a temperature decrease of the gas. A pilot system was trialed in our R&D unit. Satisfactory results led to the development of an industrial system based on Envirocare equipment (partnership), which was trialed in our production plant in Tomago (NSW, Australia). This patented system was then generalized in this plant, which is now using it with success during austral summer.

Jan 1, 2006

By Schneider, W. G.

IT is not my purpose to burden you with many statistics. The charts herewith should be considered merely as indicating the trend. I believe' that is what is really of interest to us. It is difficult, if not impossible to forecast with any assurance future developments, because of possible new mines, competitive materials, curtailment' or increase in the use of the metal in certain markets, and many other factors that have a vital bearing on any industry. Fig. 1 shows United States smeltet output of copper, starting with 1845. It is estimated that in 1928 the smelter output of copper will be about 1,010,000 tons. Between 1895 and 1905 it increased about 200,000 tons, and between 1905 and 1915 about 240,000 tons. Between 1915 and 1925 the increase was about 140,000 tons. This is an average increase over 30 years of about 190,00Q tons per ten-year period. At the present time the indications are that this demand for increased production will continue. As to whether or not we have the supplies or facilities to maintain this increase or a greater one, remains to be seen. Provided it is possible for United States smelters to increase their production, they should be producing at the rate of about 1,210,000 tons or more per year by 1935.

Jan 1, 1928

By C. A. Hunt

The problem of materials balancing is reviewed with particular reference to the minerals industry. A broad statistical framework is established that, besides extending the classical estimation problem, allows questions concerning the value of sample information to be addressed. The following are examples of such questions: How much money should be spent on sampling? Which streams in a plant should be sampled? What should be sampled? The approach adopted makes use of Bayesian analysis. The discussion includes an illustrative example involving a simple flotation circuit.

Jan 1, 1985