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By Robert J. Hundhausen

The Young America lead-silver-zinc mine in Stevens County, Wash., was investigated by the Bureau of Mines during parts of 1946, 1947, and 1948. Results of the investigation are described herein. The mine is 1/4 mile northeast of Bossburg, Wash., the nearest railway station. An excellent paved highway (No. 22) connects Bossburg with Colville, Wash., 23 miles to the south. The property was located in October 1885. It is credited with a production of 2,178 tons of shipping ore since 1901. The shipping ore averaged 7 percent lead, 7.7 percent zinc, and 16.1 ounces silver per ton. The property is under lease and option to Walter E. Morris and Perry Leighton of Colville, Wash. The deposit crops out on a steep limestone bluff overlooking the Columbia River. The country rock is a highly metamorphosed, brecciated, marbleized limestone (Northport formation).

Jan 1, 1949

By John J. Henn

An evaluation is presented of the Bureau of Mines process for the recovery of metal and mineral values from municipal incinerator residues. This process employs standard mineral beneficiation techniques and is operating on a pilot-plant scale of 1,000 pounds of incinerator residue feed per hour. Products from this separation process include ferrous, aluminum, and copper-zinc scrap, and colorless and colored glass. Cost estimates were prepared for four plant sizes. The estimated capital and operating costs For the four plants follow: [ ] It is assumed that the separation plant is located adjacent to a municipal incinerator. Provision is made, however, for part of the residue feed to be delivered by truck so that one large separation plant can be used for residue from more than one incinerator.

Jan 1, 1971

By M. L. Fenger

This report describes a study of the factors which affect medium voltage (661 - 1000 volts) and high voltage (1001 - 7500 volts) trailing cable couplers for use in underground coal mines to connect trailing rabies. Improvements in quality, dependability, and safety of medium and high voltage couplers are presented in the form of requirements for couplers. The results of an investigation of high voltage trailing cable coupler design and of whether trailing cable couplers must have a metallic shell as required by CFR 30 part 75.805 are presented. Conclusions and recommended research programs are included that describe the present situation and future development approaches.

Jan 1, 1978

By R. Newman

An inexpensive slow-speed data acquisition system has been adapted to digitally record multiple parameters simultaneously at intervals of 15 seconds. The system was built for use with standard soils testing equipment to automatically record load and displacement parameters at predetermined instants in time. Simultaneous readout is achieved by the use of special signal conditioner and sample-and-hold circuits which read the multiple signals simultaneously and hold them until the slow acting system can print out. Three channels of a 10-channel system have been converted and found to operate successfully during a series of direct shear tests. A unique feature of the system, which significantly reduced its cost, is the power supply units. Dummy circuits are used to maintain a constant power demand during sampling) thus eliminating the need for a costly power supply with rapid response characteristics. The entire system, having an overall accuracy of 0.25 percent, was put in operation for a cost under $2,500.

Jan 1, 1970

By Stan Henning

The monthly summary of the climatological record for the demonstration mine is presented in Table 1. Tear normal temperatures occurred throughout the growing season. From May to October precipitation was more than normal except in June when it was 2.55 inches below normal. Corn and soybean plantings were delayed until June 2-7 because of wet field conditions. This is about one month later than normal for corn planting. Insect infestations were much less than those encountered in previous years. Cutworm activity was not noticed and alfalfa weevil infestation were small and patchy. Stalk rot in corn was a significant problem at harvest and resulted in much Milk lodging. The wet and generally overcast conditions of July, August and September were bend 10 beneficial al to certain plant disease organisms. For example, pumpkins planted in a small garden area at the demonstration mine did not ripen because of a powdery mildew resulting from overcast, wet conditions. Field operations and row crop plantings were greatly delayed by wet field conditions. It was difficult to plant by conventional tillage because the soil remained soft and sticky where the moldboard plow had been used. Plots in the no-tillage system could he planted before conventionally tilled plots could be traversed. Plant emergence and plant density at

Jan 1, 1982

This manual provides instructions for installing, operating, and maintaining a protective canopy on the Joy Mfg. Co. shuttle car. These instructions are based upon actual installations made in the mine on two shuttle cars, model 21SC-2E. The parts list and engineering drawings for the protective canopy are included at the end of the manual. And a discussion of some alternative design concepts is also included. The manual can also be used for retrofitting other shuttle cars with similar protective canopies. Skilled mechanics can determine if the instructions hexein would he applicable to the other shuttle cars and can determine any necessary modifications if they are not.

Jan 1, 1973

By J. J. Forbes

Ventilation is the most important safety factor in the production of coal because on it depends the safety, health, and efficiency of those who work underground. Without adequate and efficient means of supplying fresh air to the working faces, mining could not have advanced as it has. The extent of the workings, the increase in mechanization, and the increasing use of electricity are largely responsible for changes in methods of ventialtion. Ventilation in the early, days of coal mining was accomplished by means of a natural draft, created principally by a difference in the weights of columns of air between the intake and return openings: Later the furnace was introduced for the purpose of increasing the quantity of air in circulation. Mines continued to become larger, their output increased, men were employed in greater numbers, and more fresh coal surfaces were exposed. Coal beds near the surface, and practically free from explosive gas became exhausted, and deeper beds that liberated methane were opened as development advanced. Mechanical ventilation became necessary and was first accomplished by disc-type steam driven fans she old-.fashioned steam driven disc fan has generally been supplanted by the powerful electrically operated centrifugal fans in use at modern coal mines. In order to be secure against gas explosions and provide ample fresh air for persons employed in large coal mines, air must be conducted through the mine to all working places and to all other unsealed parts of the mince in sufficient quantities to dilute and render harmless all dangerous and noxious gases.

Jan 1, 1929

By Lucia Kuizon

The Cactus Springs Roadless Area Review and Evaluation (RARE II) study area (No. A5188) comprises 12,800 net acres (5,180 ha) in San Bernardino National Forest in west central Riverside County, California, about 20 air miles (32 km) southeast of Palm Springs. Mineral investigations are made by the U.S. Bureau of Mines on National Forest lands identified as Further Planning Areas in the RARE II program. The Bureau of Mines reviewed literature, mining claim records, and production files; examined the study area; and mapped and sampled mineral properties where appropriate.

Jan 1, 1983

By Robert L. Lagace

This final report documents the work done by Arthur D. Little, Inc. (ADL) on behalf of the U.S. Bureau of Mines, Pittsburgh Mining and Safety Research Center (PMSRC), on Contract R0122026 (which began in August of 1971). Under this contract ADI provided technical assistance to the Bureau on a task basis on virtually all aspects of the Bureau's programs related to present and planned emergency and operational communications and miner location systems for underground coal mines. The work consisted of independent investigations, analyses, experiments, breadboard and prototype hardware development, workshops and technology transfer seminars on mine communications, and on-going evaluations and guidance related to the Bureau's contracted programs on electromagnetic noise, mine communications systems, and trapped miner location. This final report documents the work in two volumes, Volume I, "Emergency and Operational Mine Communications," and Volume II, "Seismic Detection and Location of Isolated Miners." The Tables of Contents of both Volumes are included in each Volume. Phase I of the contract was devoted to performing an in-depth assessment of electromagnetic noise measurements taken by several contractors and other investigators, and then defining a new noise measurement program and instrumentation system tailored to obtain the necessary but missing noise data. These data are required for use in the design of new emergency and operational communication systems. This work, and the follow-on coordination and guidance activities of ADL on this noise measurement program in subsequent phases of the contract, are treated in Part One of Volume I.

Jan 1, 1974

By Clarence A. Wright

The Missouri-Kansas-Oklahoma lead and zinc district, better known as the Joplin district, includes the mines in southwest Missouri and in those parts of Kansas and Oklahoma that are directly adjacent. (See PI. I.) This report of investigations carried on by the Bureau of Mines gives the methods used in mining and milling and indicates in some detail the conditions that affect the efficiency of those methods; it does not attempt to discuss the geology of the district, except incidentally, as this has been described in numerous reports by several geologists. Some of the more important recent publications are those of the United States Geological Survey by Smith and Siebenthal, a Bain, b and also those of the Missouri State geological survey by Buckley and Buehler." Other reports are those by Schmidt and Leonard," and Winslow,e of the Missouri geological survey, by Haworth and Crane,! of the Kansas geological survey, and by Jenney.g Although the lead and zinc ores are closely associated, the proportion of zinc ore mined at present is far greater than in former years. For this reason and because the losses in milling zinc ores are proportionately greater than in milling those of lead, the zinc ores are here given most consideration. Only the mines and mills actually examined and tested are discussed in detail, statements of results being restricted to the mines in general, with no special reference to anyone mine. Several mill tests were made to determine in a general way the efficiency of the milling practice in this district and to discover at what stage of the process the losses were greatest. Making these mill tests proved difficult,for, because of the arrangement of the mills and the necessity of estimating the tonnage treated, systematic mill testing and sampling can be done at only a few plants. Many tables giving results of mill tests and screen tests have been omitted because they would serve only to emphasize the important points shown by other data given. The writer has tried to bring out the possibilities of making certain improvements that would effect a greater saving, and has endeavored to avoid the use of technical terms and phrases in order that all statements may be clear and easily understood.

Jan 1, 1918

By Robert W. Metcalf

Since the spread of the European war virtually cut off imports from Denmark, Belgium, and France, the Bureau of Mines has had numerous inquiries as to domestic sources of grinding pebbles and silex or other types of ball mill liners. USES Flint pebbles and tube-rill liners are used by grinders of certain ceramic materials to prevent contamination of the finished product by iron abraded from steal baler and liners. The feldspar industry is one of the largest users of flint grinding mediums; they are employed also by curtain grinders of talc and soapstone, ground sand and sandstone, quartz, and chalk. Some paint materials, such as lithopone, have been ground in pebble Flint pebbles have been used more or less in the past, especially by cement manufacturers, and, for fine grinding of gold, copper, or other ores in which iron contamination is not especially deleterious.

Jan 1, 1940

By Tom Tallone

In the majority of metal and nonmetal mining operations, narrow vein deposits are being mined with slusher hoists. Thin; method of mucking is costly, due in part to its inherent labor intense operation and to its inability to muck 100 pct of the deposits. Mechanized equipment would greatly improve the material handling in narrow vein mining and would dramatically reduce the operational cost. The Compact Loader/Trammer, known as the "mini-mucker" has been developed to increase productivity of the load/haul/dump portion of the typical narrow vein mining cycle. This is Volume II of the final report and concerns the operation and maintenance of the mini-mucker. Volume I covers a general and design review of the activities on the subject contract and are available under separate cover.

Jan 1, 1985

[RESULTS OF THE PRIMARY CONVENTIONAL PERFORMANCE AND COST MODEL OF THE UNIT OPERATIONS OF UNDERGROUND PERCUSSIVE DRILLING AND BLASTING]

Jan 1, 1977

By C. B. Manula

This report is volume 4 of at. eleven-volume final report for a Grant completed by The Pennsylvania State University for the Bureau of Mines to develop a dynamic general purpose computer simulation model for underground coal mining. The simulator developed under the Grant has a wide range of possible applications in the design and evaluation of underground coal mining systems from the standpoints of health and safety, productivity, and mine environment: The Master Design Simulator consists of nine free-standing function-oriented subsystem models linked together into an integrated, comprehensive model of an entire mining system. The subsystems comprising the Master Design Simulator include geology and reserves, methane generation, roof support, subsidence, production, rail haulage, cost, water generation,' and ventilation. This volume of the final report describes the Roof Support subsystem of the Master Design Simulator. This model is based on popular roof support practices for different geological environments with related restrictions imposed by the Coal Mine Health and Safety Act of 1969. From geological sections, the model determines the anchor horizon for roof bolts and the density of roof support necessary. The roof support subsystem is tied to both the geology and reserves subsystem and the production subsystem of the Master Design Simulator, but can also operate as a free standing model. Several case studies are presented showing the application of the model. A detailed user's manual, including a program listing, is presented in the appendices.

Jan 1, 1974

By Ronald T. Mayerle

The Condrey Mountain RARE II area lies mostly within the Elliot Creek mining district, a significant producer of gold from placers, and gold, Silver, copper, and minor soapstone from lode deposits. No mineral production has occurred within the study area; no resources are known in the area. However, significant resources in lode and placer deposits are just outside the west and northwest boundary of the area. The Blue Ledge Mine (fig. 1, no. 15) adjacent to the western boundary, is reported to contain 226,000 ton; (205,000 t) of identified resources averaging 0.05 oz gold per ton (1.7 g/t), 2.16 oz silver per ton (/4.0 g/t), 3.5 percent copper, and 3.95 percent zinc. The mine has produced 11,131 tons (10,114 t) of ore that yielded 1,026 oz (31,908 g) of gold, 58,431 oz (1.8 million g) of silver, and 2.7 million lb (1.2 million kg) of copper. Exploration is currently underway at `he mine and vicinity, including part of the study area.

Jan 1, 1983

By Ted A. Lewtas

The effectiveness of induction fans in ventilating dead headings was studied in the laboratory and underground. The following fan attachments were evaluated: a. Aerodynamic nozzle b. Various lengths of vent tube c. Honeycomb airflow straightener. Various fan locations were also tested. The following conclusions were reached: a. A nozzle on a fan located against the drift wall gives the greatest jet penetration distance. b. Air straighteners are ineffective in increasing jet penetration. c. Induction fans are ineffective in removing contaminants from dead headings without sufficient main ventilation flow.

Jan 1, 1980

By P. D. Lohn

The objective of this program was to develop nozzle designs to maximize the effective cutting length of a water jet. The results of the theoretical program directly support the Bureau of Mines Borehole Mining Program and their experimental program to improve the rock cutting capability of water jets. The borehole geometry requires turning the flow by 90 degrees and accelerating through the nozzle within a restricted length. Several suggestions for turning the flow are offered. The borehole space limitations constrain nozzle length, to the extent that a standard 13-degree tapered nozzle (6-1/2 degrees half angle) is too long to fit in the borehole, at production flow conditions. The design technique developed is computationally economical and enables examination of a large number of shapes and flow conditions. The nozzle design is based on design criteria of minimization of boundary layer thickness at the nozzle exit and minimization of the possibility of separation and cavitation. Six flow conditions, including pressures to 4500 psi and flow rates to 400 gpm, were examined, Best shapes were determined for all flow conditions. The best shape for a borehole reining application consists of an initial 4th degree polynominal (quartic) at the entrance followed by a straight section with a twenty degree (half-angle) taper at the exit.

Jan 1, 1976

By Joe Maher

Adequate mine roof support to insure the safety of men and equipment is essential to successful mining. It is also expensive, amounting to more than one-fifth of the total mining cost at the White Pine mine. Cost effectiveness is therefore a prime consideration in developing optimum roof support. Roof bolt length is an important cost factor. This Phase II work compared uniform four-foot length Resin Bolts with the hitherto standard alternating four-foot and six-foot Resin Bolts, aiming at more cost-effective roof bolting. The data generated under this Phase II show that there is no discernible difference in the roof support given by uniform four-foot, and by alternating four- and six-foot, Resin Bolts in the relatively difficult ground selected for a severe initial test comparison; subsequent data from less difficult ground led to the same conclusion, namely no discernible difference between four-foot and four-six foot bolting.

Jan 1, 1975

By Thomas C. Denton

In 1965 Africa maintained its position as a region of the world essential to advanced non-Communist nations for supply of vital metals and minerals. The position stemmed from the fact that Africa produced in large quantity a number of key minerals of which either or both resources and production capacity elsewhere did not approach the needs of the free world. The Republic of South Africa alone contributed more than three quarters of the gold mined in the entire non-Communist world besides an estimated 60 percent of metals of the platinum group and the entire new supply of amosite asbestos, and Africa as a whole was nearly the non-Communist world's only source of gem and industrial diamond. Africa also accounted for 83 percent of non-Communist world cobalt production. Besides these massive contributions, Africa in 1965 provided 50 percent or more of the new supply from non-Communist countries of the following mineral commodities: Lithium minerals, corundum, manganese ore: and chromite, and over 20 percent of new supply from non-Communist countries of columbium-tantalum concentrates, antimony, beryl, vanadium, phosphate rock, and copper. Africa also accounted for 18 percent of the non-Communist world's output of uranium, 14 percent of its tin, 11 percent of its lead, 9 percent of its zinc, and 8.9 percent of its crude oil output. With respect to chromite, at yearend Africa's reserves of the mineral were far larger than those of all other non-Communist regions combined. This probably also held true for manganese ore. In the case of crude oil, the fact that Africa's share of non-Communist world output was 1.6 percentage points greater than in 1964 was significant, particularly inasmuch as the output rate was continuing to increase at yearend.

Jan 1, 1967

By E. H. Burroughs

This bulletin is the sixth in the series of petroleum bibliographies published by the Bureau of Mines, Bulletins 149, 165, 180, 189, and 216 being compilations for the years 1915, 1916, 1917, 1918, and 1919- 1920, respectively. In this bulletin the same general plan has been followed in arranging the references, but one or two additions have been made in the classification.

Jan 1, 1921