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By A. C. Johnson

The T. L. shaft of the Eureka Corp., Ltd., near Adams Hill, Eureka, Nev., was sunk in 1954 and 1955 to permit exploration and development of the lead-zinc-silver ore that had been indicated by drilling. This paper describes the sinking of the 4-compartment, vertical shaft to a depth of 1,127 feet and includes pertinent details of equipment, methods, and costs. A shaft crew of 10 men, supplemented by 13 hoistmen, topmen, carpenter, and shop crewmen, sank and timbered the 1,127 feet of shaft in 630 workdays. Total labor per foot of shaft was 107.95 man-hours. Supplies per foot of shaft included 20 pounds of explosives, 1.61 pounds of drill steel, and 200 board-feet of timber. Power consumption, including that required for pumping, averaged 3,726 kw.-hr. per foot.

Jan 1, 1958

By W. R. Hardwick

This paper describes mining methods and practices of the Chino Mines Division, Kennecott Copper Corp., Grant County, N. Mex. It is one of a series being prepared by the Bureau of Mines on mining methods, practices, and costs in various mining districts of the United States. A similar program was conducted from 1928 to 1939, which helped to improve the efficiency of mining operations. The primary purpose of the program is to promote development and conservation of our mineral resources by disseminating technologic information on methods, practices, and related features in mining mineral deposits. It is expected that the program will: (1) Promote efficiency in operating mines; (2) assist operators and engineers in evaluating and developing new mineral deposits; (3) provide data for engineering curriculums in mining schools; and (4) furnish performance and cost data for revising engineering handbooks and for inclusion in engineering textbooks.

Jan 1, 1958

By Albert E. Long

This paper presents a description of the operational mechanics involved in block-caving a granodiorite-capped, limestone deposit. This method was used for 24 years at the Crestmore mine, near Riverside, Calif., which was operated by the Riverside Cement Co. as a source of raw material used to manufacture a portland cement. The Crestmore mine is the only place where a block-cave method has been used to mine a limestone deposit. Structurally, limestone is relatively strong, and it is not usually considered to be a substance amenable to mining by block caving. It is therefore a credit to the engineering department of the Crestmore mine that it developed a satisfactory, relatively efficient method of block-caving a structurally stable rock. In the discussion, covering the methods applied to produce about 7.9 million tons of limestone and granitic rock materials by block caving, particular emphasis has been placed on an assessment of (1) physical properties of the deposit, (2) ground pressure and support, (3) methods used to induce fragmentation and maintain cave action, (4) surface and subsurface subsidence, (5) secondary blasting of oversize, (6) production rate, (7) safety, and (8) the advantages and disadvantages of the cave method as applied to this specific limestone deposit.

Jan 1, 1958

By P. J. Colbassani

Samples of mine atmospheres collected by Federal coal-mine inspectors during their inspections and investigations of coal mines, in accordance with provisions of the Federal Coal Mine Safety Act (66 Stat. 692; 30 U. S. C., sees. 451-483) are analyzed routinely by chemical methods at Bureau of Mines laboratories. When samples collected in open workings of nongassy coal mines at points not less than 12 inches from the roof, face, or rib contain 0.25 percent or more methane, the act requires the operator, during operation of such mine, to comply with the provisions of sec. 209, Title II, of the act, which pertain to gassy mines. The methane con-tents of such samples are determined by a physical method based on infrared absorption spectrometry to provide an independent check on analytical results obtained by chemical methods. This information circular describes the equipment and procedures used by the Bureau for determining low concentrations of methane in coal mine atmospheres by infrared absorption spectrometry. ACKNOWLEDGMENTS The authors are indebted to Dr. R. A. Friedel, Chief of Spectrometric Section, Branch of Coal-to-Oil Research, Bureau of Mines, for suggesting the analytical method and for furnishing valuable advice and assistance, and to J. A. Queiser of his staff for making exploratory measurements by this method; to Dr. M. G. Zabetakis of the Division of Explosives Technology for his assistance during the conduct of preliminary experimentation; and to L. B. Berger, Chief, Branch of Health Research, under whose guidance the equipment was procured and the work conducted.

Jan 1, 1958

By E. J. Gleim

The Bureau of Mines customarily publishes lists of equipment meeting its safety standards to keep the mining industry informed as to the development and availability of mining equipment that can be used safely. The present list supplements Bulletin 543, Permissible Mine Equipment Approved to January 1, 1953, as well as Information Circular 7722, Permissible Mine Equipment Approved During the Calendar Years 1953-54. Because standards have been revised and new ones added by the Bureau, this list contains classes of equipment not previously covered.

Jan 1, 1958

By John C. Machisak

THE INJURY data and related employment experience of the coking industry in the United States for 1955 arc presented in this publication under the following general sections: (A) General Injury experience: Tables 1 to 9: Contain current and comparable data on operating statistics, number and classification of injuries, injury-frequency rates, and accident agencies involved in causing injuries. Data are tabulated for the industry as a whole, for each typo of oven: and for the States in which coke is produced.

Jan 1, 1958

By John C. Machisak

THE INJURY data and experience at quarries and related plants of the United States are presented in this publication under the following general sections: (A) General injury experience: Tables 1 through 3: Contain current data on the number of injuries, injury-frequency rates, location, accident agency, degree of injury, and related employment data. (B) Injury experience at different kinds of quarries: Tables 4 and 5: Contain current, data on number of injuries, injury-frequency rates, locution, accident agency, degree of injury, and related employment data. (C) Injury experience by States: Tables 6 through 19: Contain current data on the number of injuries, injury-frequency rates, accident agency, degree of injury, and related employment data.

Jan 1, 1958

By Alvin Kaufman

Increased exploration in Alaska has resulted in many requests to the Bureau of Mines for facts about the mineral resources and mining conditions in the Territory. This report presents information about the minerals of Southeastern Alaska and the factors that affect development of a mining industry in that area. Southeastern Alaska is a narrow coastal strip of rugged mountains and many islands. The climate is mild, with an average annual temperature of 40° and heavy rainfall. Geologically, the region is favorable for deposition of ore; geographic-ally, it is difficult to prospect and to develop, except along areas immediately adjacent to the coastline.

Jan 1, 1958

The method of using large-diameter augers to recover coal was introduced to the mining industry about the end of World War II, and production of bituminous coal with augers has increased steadily to an estimated 7 million tons, or approximately 1.4 percent of the total mined in 1956. Although auger mining has proved to be a reliable and economical method of mining coal, a number of unfortunate fatal accidents have been experienced; consequently the need for these recommended safety standards is indicated for this comparatively new method of coal mining. As mining methods and equipment change from time to time and new hazards are introduced, these standards will be revised; therefore, questions or suggestions from the coal-mining industry will be welcomed and carefully considered.

Jan 1, 1958

By R. O. Pynnonen

Tunnel-driving is recognized as a hazardous occupation; adequate support of roof and sides for preventing accidents from falling material is usually one of the most important safety problems. Where extraordinary conditions of sand and water are found, this problem becomes even more difficult. Tunneling at the Tioga No.2 mine was stopped when a 22-foot bed of water-saturated, fine gray sand was encountered. The tunnel, designed to house an ore-conveyor belt, was being driven from both ends. Driving was extremely difficult at both the upper and lower faces when the sand horizon was reached. A distance of 178 feet remained between the faces. Heavy pressures deformed the steel-supporting rings at the upper face, and there was an inrush of mud and sand at the lower face.

Jan 1, 1958

By Sidney Katell

This report is the fourth in the series, Bibliography of Investment and Operating Costs for Chemical and Petroleum Plants. The initial work, Bureau of Mines In- formation Circular 7516, was published in October 1949 in conjunction with the synthetic liquid fuels program authorized by Public Law 290, 78th Congress. It included references to and abstracts of publications appearing from 1930 to September 1948 on all processes in general use in the petroleum refining and chemical industries. A supplemental bibliography, Bureau of Mines Information Circular 7705, was published in January 1955 to cover the period September 1948 through June 1952; and Supplement 2, Information Circular 7751, published in September 1956, covered the period June 1952 through June 1954. The present supplement covers the period July 1954 through December 1956.21 The information in this paper was obtained from the following sources: 1. Bureau of Mines Information Circulars. 2. Bureau of Mines Reports of Investigations. 3. Chemical Engineering. 4. Chemical Engineering Progress. 5. Chemical Engineering Costs Quarterly (Cost Engineering).

Jan 1, 1958

By M. Clair Smith

This report is one of a series describing exploration, development, mining methods, and costs at United States open-pit mines; the Bureau of Mines prepares and publishes them in cooperation with the mining companies. Their purpose is to promote development and conservation of our mineral resources by disseminating technologic information on mining methods and practices at various United States mines. The exploration, development, equipment, and mining of a large, oxidized-copper ore deposit by open-pit methods, the leaching of the ore with sulfuric acid solution, and the recovery of the copper as cement copper are described herein.

Jan 1, 1958

By Frank L. Wideman

This information circular describes methods used in mining inclined beds of phosphate rock in mines operated by San Francisco Chemical Co. in Rich County, Utah. The mines are on the western flank of the Crawford Mountains, a short, narrow range in northern Utah near the Idaho-Wyoming corner (fig. 1). The western front of the range is a conspicuous wall of folded and faulted sedimentary rocks that rises abruptly 300 to 600 feet above the floor of the adjacent Bear River Valley. Rex Peak, highest point in the range, is approximately 8,000 feet above sea level. The area surrounding the mines is sparsely populated. Randolph, the county seat of Rich County, has a population of 650. It is 10 miles southwest of the mines by road and the only town in their vicinity.

Jan 1, 1958

By H. F. Weaver

The 17th National First-Aid and Mine Rescue Contest was held in the Kentucky Fair and Exposition Center, Louisville, Ky., October 2, 3, and 4, 1957. The meet was under the auspices of the Federal Bureau of Mines and the Joseph A. Holmes Safety Association, in cooperation with the National Coal Association, United Mine Workers of America, State mining departments, local mining institutes, and coal operators' associations. The Arrangements Committee, as authorized by the General Committee, made all the necessary arrangements for conducting the 1957 contest. Members of the Arrangements Committee were: Harry Gandy, Jr. (chairman), National Coal Association; James B. Benson, Southern Coal Producers' Association; Charles Ferguson, United Mine Workers of America; George C. Trevorrow, Bituminous Coal Operators' Association; and James Westfield, Federal Bureau of Mines.

Jan 1, 1958

By W. O. Philbrook

Reduced-scale models have long been used in hydrodynamics, aerodynamics, and heat transfer for studying fundamental flow relations or the performance of prototype designs under prescribed conditions. The pilot plant is a common tool of chemical engineering for investigating process variables and as an integral step in developing a new process. The metallurgical industry was rather slow to recognize the applicability of these techniques to some of its established and rather complex processes, but there has been a rapidly increasing number of applications of the principles of modeling in process metallurgy since World War II. Not only have pilot-scale operations been employed for developing methods of extracting metals that have recently achieved commercial importance, as well as new processes for some of the commoner metals, but models have also been used for engineering studies aimed at better understanding of the controlling, variables of time-honored conventional processes, It appears that the principles of similitude have become accepted as a useful tool, when properly applied, in metallurgy as in other fields of engineering. Much of the work of the Pyrometallurgical Laboratory, Region V, involves study of high-temperature smelting and refining processes for ferrous and related metals in pilot-scale equipment, such as the experimental blast furnace, converter, open-hearth, arc furnace, and rotary kiln. It was appropriate for the work of this laboratory that guiding principles for designing apparatus and interpreting results should be set down and that a bibliography of related work should be available for reference. A summary of the principles of model study and a brief review of some of the more noteworthy general papers have been published elsewhere.3/ Also, the Bureau of mines plans to publish a report of investigations describing its experimental work in this field. The bibliography is presented here as a service to others who may have use for it.

Jan 1, 1958

By P. C. Van Natter

Numerous mine fires have resulted in high death tolls and considerable finan¬cial loss during the history of coal mining. In most instances the death toll and financial loss were greater because of inadequate fire-fighting facilities. The information in this report is presented in the hope it may serves as a guide in the selection, placement, and care of fire-protection systems in similar coal mines. The adequacy of fire protection varies according to size of operation, employment, and production. When fires occur on the surface or underground, measures must be applied quickly to prevent incipient fires from spreading. The record of coal-mine fires shows that, in many instances, facilities for combating fires were very meager or were absent. It would be virtually impossible to establish and maintain all the necessary facili¬ties that may be needed to extinguish widespread mine fires, but it is believed that the coal industry can ill afford less than the minimum required by other industries where the time element and avenues of escape are much more favorable.

Jan 1, 1958

By D. S. Kingery

The practice of using doors to control main ventilating currents in bituminous-coal mines is common throughout the industry. When doors are erected in pairs to form air locks, they are usually accepted as satisfactory by both State and Federal coal-mine-inspection agencies. A review of the contributing factors in recent methane ignitions showed that interrupted ventilation (often caused by doors latched open, destroyed, or damaged) was the principal cause of methane accumulations that subsequently were ignited.

Jan 1, 1958

By A. C. Johnson

This report describes exploration, development, and exploitation methods, and summarizes costs at the Stormy Day mine, which was discovered in 1941. Several shipments of tungsten ore were made in 1944 to the Metals Reserve Company, Salt Lake City, Utah. The purchase of tungsten by the Federal Government, which began in 1951, stimulated interest in tungsten, and a successful program of exploration with participation of the Defense Minerals Exploration Administration (DMEA) indicated enough ore to warrant development of the property. Development work comprised drifting, crosscutting, and raising. Shrinkage stoping was used for mining the ore. Operations were suspended in October 1956, when the Federal Government terminated its purchase program. Total production of the mine was approximately 20,000 tons of tungsten ore. INTRODUCTION This information circular is one of a series, prepared in cooperation with various mining companies and published by the Bureau of Mines, relating to methods and costs of equipping and developing mining properties in the United States.

Jan 1, 1958

By L. Nahai

In two decades Turkey has emerged from the debacle of the Ottoman Empire to become one of the most modern nations in the Middle East. The numerous achievements of this period were remarkable in that they affected human and social, as well as economic, fields. Most of this progress was achieved by Turkey's unaided efforts and the utilization of domestic resources; however, since 1948 various United States aid programs3/ have made significant contributions to increased agricultural and industrial output. Turkey's singleness of purpose in favor of a strong, independent, and prosperous republic has evoked universal admiration and encouraged the hope of stability in the Middle East. Much of the development of the Turkish economy to date has been fostered by the State; however, with growing strength the leaders in 1950 considered the time appro¬priate to relax the nationalistic economic policy and permit private enterprise to play a larger role in increasing domestic output and raising the tempo of industrialization. In pursuance! Of this policy, laws encouraging investment of foreign capital in Turkey and others stimulating development of mining and petroleum enterprises were enacted in 1954. This new legislation, plus the cooperative attitude of the Turkish Government, have encouraged wide interest in the mineral resources of the country.

Jan 1, 1958

By Charles Zahn

Gas chromatography is a method of separating mixtures of gases and volatile materials by entraining their vapors in a gas stream, which passes over an appropriate stationary phase. Two techniques are in common use: Gas-Liquid Chromatography, in which the stationary phase is a liquid supported on an inert solid, and Gas-Solid Chromatography, where the stationary phase is a solid adsorbent, such as charcoal or alumina. In both techniques components emerge from the column after a characteristic residence time. Gas chromatography is applicable as a qualitative or quantitative tool in a wide variety of problems in chemical research and processing. It may also be employed for purification and separation. A running bibliography on gas chromatography has been maintained at the Bureau of Mines synthetic liquid fuels laboratories, Bruceton, Pa., for several years for the benefit of research workers, who use chromatography as an analytical tool. Since the number of references grew and interest in the technique became more wide-spread, the Bureau is publishing this list rather than maintain it as a purely internal source.

Jan 1, 1958