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By Lucia Kuizon

The Pinnacles Wilderness Contiguous Wilderness Study Area (WSA) (CA-040-303) is 30 miles south of Hollister, CA, in San Benito and Monterey Counties. It is composed of five parcels of public land totaling 5,838 acres adjacent to the Pinnacles National Monument. The U.S. Bureau of Land Management later reduced the size of the Recommended Suitable Area (RSA) to 2,200 acres. U.S: Bureau of Mines personnel examined the entire WSA in May 1984. The WSA is underlain by Tertiary sedimentary and Cretaceous plutonic rocks. Diatoms occur in interbedded tuff, shale, and sandstones in the northern part of the WSA, but outside the RSA. In 1984, there were no mines, prospects, mining claims, leases, or mineral resources in or within one mile of the study area. No energy minerals were identified; however, an oil well was drilled in 1951 in the northern part of the WSA, but outside the RSA; it was a dry hole.

Jan 1, 1985

By C. S. Tout

While investigating methods for determining the best temperatures for hot-working experimental stainless steels, the Bureau of Mines Albany Metallurgy Research Center developed a machine in which hot-twist tests could be made in a few minutes. This machine is similar to some used previously except that specimens are heated by induction instead of by radiation, and their temperature is measured by a calibrated radiation-detection unit instead of by a thermocouple. In. developing the technique for using the new machine, tests were made on specimens of medium-carbon steel, mild steel, and AISI (American Iron and Steel Institute) type 304 stainless steel. Tests also were made on as-cast specimens and preworked specimens of experimental AISI type 202, low austenitic stainless steel, and as-cast specimens of AISI type 301 experimental stainless steel. The optimum hot-working temperatures were determined for all types of steel tested. Also, data were gathered on the effects of test speed and temperature on torsional strength and the effect of twisting on tensile stress in the specimen.

Jan 1, 1962

By D. S. Kingery

Recent Federal coal-mine inspections have revealed some good and some definitely hazardous practices and systems for transporting; handling, and storing lubricants in and about coal mines. Improper storage or handling of. lubricants in coal mines has caused disastrous mine fires or, by supporting combustion, has made fires from other sources more difficult to fight. Careless handling of grease and oil around electrical equipment wastes much oil and permits entrance of grit and foreign substances into the working parts, which causes excessive wear and increases the possibility, of electrical ignition.

Jan 1, 1943

By S. H. Ash

The paramount responsibility of Government is to protect the general welfare. One of the chief functions of the Bureau of Mines is to investigate and publicize methods of increasing safety and efficiency in mining operations. In an industrial civilization, energy resources constitute the foundation of a sound economic structure (14).4/ Coal is only one source of energy, but it provides more than half the energy consumed in the United States.

Jan 1, 1946

By Harold J. Polta

This Bureau of Mines publication considers the feasibility of augmenting the present transportation system by pipelining taconite concentrates from the Mesabi Range to the Chicago area. The cost of pipelining in the hypothetical system using water as the carrier is estimated to be between $3.66 and $3.97 per long ton. This appears competitive with the 1970 rail-vessel transportation rate of $4.08 even after allowing a few cents per ton for barging from the terminal to existing furnaces. Political obstacles requiring solution before such a pipeline could be built and the feasibility of using crude oil as the carrier fluid are also discussed. FORTRAN routines used to calculate unit transportation cost for specific estimated values of cost items and for a range of values are presented. The effect of deviations from estimated values of cost items on the total unit transportation cost are shown graphically.

Jan 1, 1971

By Robert J. Hundhausen, Robert M. Gammell

"INTRODUCTION Several mining properties in the Pine Creek area of the Coeur d'Alene mining region of Idaho were examined by engineers 3/ of the Bureau of Mines in 1942. As a result, a broad program of exploration was recommended for the area, particularly in the eastern end, where chances for the discovery of new ore shoots seemed favorable. This report describes the work done and the factual information obtained by the Bureau of lanes.ACKNOWLEDGMENTSIn its program of exploration of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell Be Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch,. C. C. Ralston, chief, analyzes samples and performs beneficiation tests.The exploratory work at the Sidney mine was part of the activities of the Albany Division of the Mining Branch, S. H. Lorain, chief. Field work was under the direction of R. M. Gammell.Chemical analyses included in this report were performed at Reno, Nov., under the direction of A. C. Rice, acting engineer in charge, Rare and Precious Metals Experiment Station, Bureau of Mines. The ore-dressing tests were made under the direction of S. R. Zimmerley at the Bureau of Mines laboratory in Salt Lake City, Utah.The cooperation and assistance given by the owners of the Sidney Mining Co. is gratefully acknowledged."

Feb 1, 1948

By Warren Howes, A. B. Campbell, W. H. Ode

"INTRODUCTION The mines in the eastern part of the now active region of the Tri-State zinc district of Missouri, Kansas, and Oklahoma have unusually acid water, which during periods of moderate or no rainfall is used in the mills to replace losses from evaporation, seepage, and tailings disposal. Its use has caused difficulties by corrosion of equipment and by interference with flotation.The growing importance of flotation, which requires good water, and the increasing troubles caused by the corrosion of the milling equipment have prompted the Mississippi Valley Experiment Station of the United States Bureau of Mines, in cooperation with the Missouri School of Mines and Metallurgy, Rolla, Mo., to investigate the action of the waters on flotation and to undertake to develop means of obviating their harmful effects.The work was under the immediate direction of W. T. Schrenk, consulting chemist, United States Bureau of Mines, and professor of chemistry, Missouri School of Mines and Metallurgy, and Will H. Coghill, supervising engineer of the ore dressing section of the United States Bureau of Mines.ORIGIN OF ACID MINE WATERSRain water, carrying oxygen and carbon dioxide in solution, finds its way into the pores and crevices of the earth's crust and percolates downward through the rocks. This water and its dissolved gases exert a solvent action on many minerals, the extent of which depends upon the nature of the associated minerals.The iron sulphides are the chief sources of the 'trouble with sulphates and sulphuric acid because they oxidize so freely and contain more sulphur than is required to satisfy the iron when ferrous sulphate is formed. Galena and sphalerite may oxidize to sulphates without liberating acid. A few of the common reactions occurring in the Tri-State mine waters may be illustrated by the following equations:"

Mar 1, 1932

By E. R. Maize

This report is t e second of s series on roof movement in coal mines. The first (R. I. 3355)4/ dealt with convergence of roof and floor and movement of the surface accompanying and following extraction in a mechanized mine in which retreat of rib lines was rapid. The studies reported herein were made in a mine in which all the coal is loaded by hand, and movement of the rib lines was much slower in consequence. In choosing a site for this work, it was decided that the mine selected should have natural conditions akin to those of the first study and entirely different methods of working. To this end a cooperative agreement was made with the Crucible Fuel Co. through W. J. Whitaker, secretary, for conducting the work in the company?s Crucible mine, operating in the Pittsburgh bed in Greene County, Pa, This paper gives an account of the methods used in the investigation, excerpts from the data obtained, and such generalizations as can be made.

Jan 1, 1939

By W. W. Agey

An inexpensive technique that laboratory studies indicated would significantly reduce seepage in irrigation canals was devised and tested through research sponsored by the Bureau of Reclamation and the Missouri River Basin Field Committee. Laboratory tests simulating optimum field conditions determined that easily applied sodium carbonate solutions made test beds of canal lining materials virtually impermeable for long periods. The study comprised alternative laboratory treatments of 3-inch-deep test beds of canal earths with 74 water-soluble chemicals in search of one 01' more that would effectively improve the water barrier characteristics of the component clays. Sodium carbonate, one of the least expensive, was among the most effective. The addition of 0,4 lb of reagent per sq yd greatly reduced the seepage from typical, highly permeable test beds. The reagent penetrated and sealed surface for about a 1.5-inch depth.

Jan 1, 1965

By R. H. Grau, S. B. Robertson, J. Dolgos, T. P. Mucho

The National Institute for Occupational Safety and Health (NIOSH) has developed a computer program called the Air Quantity Estimator (AQE). The purpose of the program is to provide a starting point for estimating the air quantity needed to dilute diesel particulate matter (DPM) in an underground large opening mine, albeit taking into account various input assumptions. The AQE estimates the total air quantity needed to dilute DPM emissions that enter the main airstream of the mine to current statutory levels. It helps operators pinpoint vehicles that are high DPM contributors. In addition, it allows the user to make “what if” scenarios by varying the input parameters to achieve the most efficient and practical ventilation system. The AQE is a stand-alone software program that does not require any type of spreadsheet software. Engine data must be known or estimated with some accuracy and assumptions must be made in order to limit the variability of the program output. Program calculations and two case studies, for validation purposes, are included in this report. It should be noted that the program does not ensure adequate face ventilation and personal exposure compliance.

By Robert L. Thorne

As an integral part of the investigation of critical and essential minerals in Alaska , the Bureau of Mines examined the lead deposits in the Slana area . Four examinations were made during June , July, and August 1945 in the 200 - square -mile area immediately northwest of Slana . The settlement of Slana lies near the conflux of the small Slana River with the mighty Copper River less than 60 miles southwest of Tek Junction on the Alaska Highway . Travel through the area and the examination of the properties were conducted by a three-man crew consisting of the author , a caterpillar operator , and a laborer . An RD6 caterpillar , equipped with blade and winch , was used in breaking trail and freighting through the country . Supplies and equipment were loaded on a 7- by 14 -foot , double - end , go -devil , which was hauled by the tractor .

Nov 1, 1946

By John K. Alley

Despite the extensive use of fluorphlogopite, investigators do not agree as to its exact melting temperature. Data on other fluormicas and on related fluorsilicate systems are largely nonexistent. A knowledge of the melting temperature is necessary for the effective synthesis and use of fluorphlogo¬pite or other fluormicas. The increasing use of two- and three-mica systems to yield polycrystalline ceramics has made more urgent the need for melting temperature information concerning these other fluormicas. This report is part of a program by the Bureau of Mines to synthesize large-size or large-crystal fluorphlogopite and develop a usable reconstituted fluormica sheet. The melting temperature of fluorphlogopite, K2Mg6A12Si6020F4, was found to be 1,383° ±2° C. This temperature was found by studying single crystals of fluorphlogopite, heating behavior of glass of fluorphlogopite composition, and the actual crystallization of fluorphlogopite from a melt that had been heated above 1,430° C. The formation of forsterite or norbergite was directly proportional to the loss of volatiles during the experimentation. Many trials revealed that the only reliable seal was a thick platinum sheet with welded seams. If no volatiles were lost, neither norbergite nor forsterite were formed; fluormica was then the only product. Excellently formed crystals of forsterite with an optical sign different from ordinary forsterite were obtained during the single crystal melting experiments. These crystals resulted from a slow loss of volatiles. A congruent melting of fluorphlogopite is indicated by the data of this report; however, incongruency within a small temperature range is not precluded. A more refined method using phase equilibria-quench methods would be necessary to settle the question absolutely.

Jan 1, 1962

By Robert A. Jankowski

Through laboratory and underground studies, the Bureau of Mines has evaluated the use of passive barriers (dust shields) to help confine dust generated by longwall shearers to the face area. Laboratory studies focused first on selection of the optimum barrier design, which proved to be a simple, gobside barrier (made of conveyor belting), coupled with a headgate splitter arm, which was found necessary to prevent the dust cloud from entering the walkway at the headgate end of the shearer when cutting tail to head. Further laboratory testing was done to determine whether using passive barriers in combination with different water-spray dust-reduction methods, including the shearer-clearer system developed by the Bureau, would improve dust reduction over that from using the water sprays alone. It was found that the combination of gobs ide passive barriers plus the full shearer-clearer system was most effective, and surmised that this would be especially useful in thicker seams. However, underground testing revealed that the shearer-clearer system alone was 35 pct more effective in reducing dust contamination than when used with the gobside passive barriers, and far more effective than using passive barriers with a conventional water spray system. For such an effective system as the shearer-clearer; the reduction in avail-able space over the top of the machine actually impeded system performance; this was shom1 in both eastern and western mines. But when used with comparatively inefficient water spray systems, the passive barriers, used in combination with a headgate splitter arm, provide consider-able help in reducing dust levels in the walkway.

Jan 1, 1986

By J. W. Sterner

The Bureau of Mines conducted studies on four makes of Japanese automobiles, three 1981 and one 1982 model years, received from three manufacturers to determine if their materials composition would present problems to the current technology used to process junk automobiles for metal recovery. One of each make of automobile was hand-dismantled to determine the materials composition. In addition, two nearly identical automobiles of each make were shredded at a commercial operation where all metal products and rejects were collected for analysis to determine metal and nonmetal distribution. The average weight of the four automobiles to be dismantled, less batteries, tools, and fluids, was 1,938.3 lb. The weight was distributed as 1,472.9 lb. ferrous and 115.6 lb nonferrous metals, 275.2 lb combustibles, 72.3 lb noncombustibles, and 2.3 lb electrical components. The dismantled automobiles, less gas tanks, fluids, tools, wheels, tires, and batteries, which were all removed from the automobiles that were shredded, contained an average of 1,389.1 lb ferrous and 101.6 lb nonferrous metals, 305.7 lb nonmetals, and 2.3 lb electrical components. In comparison, materials collected from the shredded automobiles averaged 1,304 lb ferrous metals, 80 lb nonferrous metals, and 341 lb landfill materials. There were no materials used in the manufacture of the late model Japanese automobiles that should present handling or processing problems to the steelmaking or secondary metal recyclers.

Jan 1, 1984

By Kathleen M. Kowalski

In emergency management, the effects of stress on the performance of emergency personnel, typically have been ignored or regarded as too enigmatic to quantify. This paper discusses the concept of Critical Incident Stress in responders to emergencies. It presents the rationale for considering stress as a significant factor in the management of emergencies. It is proposed that Critical Incident Stress Debriefing in a disaster can improve the effectiveness of response teams on site, their turnaround time on site, and post-disaster time off the job. Critical Incident Stress intervention also can mitigate potential deleterious emotional effects associated with emergency work. This paper, prepared by a U.S. Bureau of Mines researcher, offers some ideas to the mining industry in general, to mine rescue team trainers, and to developers of program simulations on the specific issue of how people, time, materials and space may be factored into a plan for emergency management. The impact of stress on emergency workers is, presented as a missing component in present emergency management models.

By Gerhard Braüner

The report gives a review of the methods of predicting mine subsidence; these methods are used particularly in European coalfields. The methods are subdivided into two groups, based on mathematical expressions either for the trough profile or for the influence of infinitesimal extraction elements. The fundamental relationships common to all methods described herein are the principles of superposition and of equivalent extraction areas. The involved parameters are derived from field observations. For calculating horizontal displacements, their relation to the slope of the subsidence profile is applied. The time-dependent development of the subsidence process is characterized by the empirical "time factor." Modifications for the case of inclined strata are considered. A brief review of experimental and theoretical model investigations is given.

Jan 1, 1973

By C. H. Gorski

Evaluation of raw materials for mineral wool is one phase of the Bureau of Mines broad program for the more effective utilization: of our mineral resources. The experimental work and test-evaluation results on several raw materials as useful components for the production of mineral wool are presented in this report. Samples from all sections of the United States, including copper slag from Tacoma, Wash., pebble phosphate slime from Florida, and granites from Massachusetts and Minnesota, have been blown into mineral wool successfully in the laboratory tests. Maximum conservation of the Nation's mineral and manpower resources requires maximum utility of those resources. Al though the domestic reserves of oil, gas, and coal are tremendous, judicious use of these fuels through the use of proper insulation will insure the highest thermal efficiency. The effectiveness of mineral wool as a heat-insulating material has assumed an increasingly important role in the national economy, and it has become a fuel saver in countless applications. The most immediate concern to many is the use of mineral wool in the home, which promotes uniform temperature and minimizes drafts by reducing heat transfer through the walls, ceiling, and floors. There are, however, many industrial and commercial uses that require large volumes of mineral wool each year.

Jan 1, 1951

By Lowell Stroud

Since 1929, the Helium Activity of the Bureau of Mines has operated a helium-extraction plant at Amarillo, Tex. The natural gas that supplies this plant is obtained from the Cliffside geologic structure 12 miles to the northwest and over the years, has become known simply as "Cliffside gas," There is need for published data on the low-temperature phase equilibria of helium-bearing natural gases. To date, little information has been published on the equilibrium phase compositions, solution of helium in condensed natural gas, condensation characteristics, or equilibrium vaporization coefficients for methane, nitrogen, and helium in helium-containing systems. A windowed phase equilibrium apparatus (8)6 was used to obtain 105 equilibrium samples, representing 35 experimental conditions of condensed Cliffside gas at pressures of 100, 200, 300, 400, and 500 p.s.i.a. and temperatures from 0° to -270° F. Data on equilibrium vapor-liquid composition for Cliffside gas are presented in both tabular and graphic form and are discussed in detail to show their relationship to certain criteria that must be met to effect an efficient separation of helium from natural gas by means of low-temperature processes. Facts about condensation characteristics and solution of helium in the liquid phases are included, The important relationship of these two factors in decreasing the percentage of total helium lost by solution in the liquid phase is discussed.

Jan 1, 1961

By Walter Kawa

Bureau of Mines research on the hydrogenation of coal has been concerned with developing processes that could be used to supplement the Nation's petroleum and natural gas resources. Motor fuel was produced in a subsidized coal hydrogenation industry in Europe prior to 1945, but the process used is still not economical and other methods of producing liquid and gaseous fuels from coal are being investigated. As an aid to the planning of coal hydrogenation research, a literature survey was made of processes or methods of hydrogenating coal that differ from the subsidized or conventional process. This report contains a bibliography of unconventional methods of hydrogenating coal and a brief discussion of the economics of the conventional method. A general discussion of unconventional methods is included, and the advantages and disadvantages are pointed out where possible. The survey supplements a previous Bureau of Mines survey3 and a comprehensive review published in 1930.4

Jan 1, 1964

By F. R. Cattoir, T. A. Sullivan

Commercial uranium metal was electrore fined to a high- purity product using molten- salt electrolytes in an inert atmosphere cell . Electrorefined uranium that contained , after consolidation , less than 30 ppm of metallic impurities was prepared . A method of leaching the electrolyte crystals to remove the salts was developed . Cathode current efficiencies from 90 to 100 percent were obtained . Two molten- salt electrolytes were prepared and evaluated : (1 ) lithium chloride - potassium chloride - uranium trichloride and ( 2 ) sodium chloridepotassium chloride - uranium trichloride . Very little difference was found in the purity of the uranium metal produced in either system . The lithium chloride - potassium chloride - uranium tri - chloride electrolyte was preferable from an operational standpoint .

Jan 1, 1964