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By Hsin Wei Wu

A real-time Diesel Particulate Matter (DPM) monitor has been developed on the basis of the successful National Institute of Occupational Health and Safety (NIOSH) designed Personal Dust Monitor (PDM) unit. The objectives of a recently completed Australian Coal Association Research Program (ACARP) study were to modify the PDM to measure the submicrometre fraction of the aerosol in a real-time monitoring underground instrument. Mine testing focused on use of the monitor in engineering evaluations to determine how conditions can be improved. Studies, including a selection during Longwall (LW) moves as described in this paper, demonstrated how DPM concentrations from vehicles fluctuate under varying ventilation and operational conditions. Correlation between the current SKC DPM measurement system and real-time DPM monitors were conducted and results from six mines show a correlation between elemental carbon (EC) and the new monitor DPM mass ranging from .51 to .81 with R2 >.90. These differences are suspected to be due to variations from mine to mine in aspects such as mine atmospheric contamination, vehicle fleet variations, fuel type, engine maintenance, engine combustion efficiency, engine behaviour or interference from other submicrometre aerosol. Real-time monitoring readily reflects the movement of individual diesel vehicles and allows pin-pointing of high exposure zones such as those encountered where various vehicles work in areas of constrained or difficult ventilation. DPM monitoring approaches that have been available for some time based on shift average monitoring do not readily allow successful engineering evaluation exercises to determine acceptability of pollution levels. Identification of high DPM concentration zones allows efficient modification of mine ventilation, operator positioning and other work practices t o reduce miners? exposures without waiting for laboratory analysis results.

Jan 1, 2010

By H. Kim, R. W. Plummer, T. J. Stobbe

"The probability of developing coal workers' pneumoconiosis (CWP) varies among miners in different geographic areas, coal seams, and jobs. Many studies have revealed the correlation between mineral content and the frequency and severity of CWP development still remains controversial. Furthermore, the mineral content and its variability in different areas is unknown.Since mineral content is expected to vary from location to location within a mine, between mines, between coal seams, and over time, this information will be valuable in understanding the variations in CWP incidence, as well as in establishing the appropriate kinds of dust to use in toxicological research programs studying CWP.Size-selective airborne dust samples were collected using 4-stage cassette impactors at 9 different locations in each of five coal seams. These coal seams were the Upper Freeport, Pittsburgh, Kittaning, Coal Burg, and Pocahontas. Mineralogical analyses were done by a x-ray powder diffraction photographic technique.Common minerals found in coal mine dust were illite, calcite, kaolinite, quartz, siderite, dolomite, gypsum, anhydrite, and pyrite. The distribution of minerals in interand intra location samples will be reported. Early results on the mineral content show wide variations between locations.in a mine and between coal seams, and small, but significant, variations between particle sizes.INTRODUCTIONIn spite of its long history of incidence, and the large amount of research conducted on it, coal workers' pneumoconiosis (CWP) is still prevalent among coal miners and needs further research to develop effective preventive and remedial measures. Although the dose-response relationship between simple CWP and coal mine dust has been established (1), the causal agent(s) and the mechanism(s) involved in the progression of simple to complicated CWP are not yet defined. Many plausible hypotheses have been made to explain the mechanisms involved in the disease progression however none of them is satisfactory. In addition, the source of variation in occurrence of CWP among miners in different geographic areas (2), rank of coal seam (3,4), and job (5) remain unsolved."

Jan 1, 1988

By R. C. Annear

This report describes open, sublevel, and shrinkage stoping at the Greenwood mine, operated by Inland Steel-Co. The iron ore mine is in Marquette County, Mich., about 6 miles southwest of Ishpeming (fig. 1). The Greenwood is one of three active underground hard-ore mines on the Marquette range, the others being the Cliffs-Shaft and the Champion mines. The operation reflects an achievement in exploiting small, difficult-to-mine hard-ore bodies lying beneath a 200-foot overburden of glacial drift, which is partly water bearing. This report can indicate only briefly the efforts of personnel in overcoming adverse conditions in mining more than 2 million tons of ore, 80 percent of which was in lump form, for open-hearth production of steel. Significant data presented include descriptions of the principal mining methods employed, sublevel and shrinkage stoping; percent aged mining costs for the entire year 1957, covering both direct mining costs and general expenses; and performance records in units of labor, power, and supplies.

Jan 1, 1960

By G. W. Grove

The Joseph A. Holmes Safety Association acid the Holmes Association have fostered many chapters that have served as a medium in increasing safety in the mining industry. Details relating to the formation, operation, and achievements of the J. J. Forbes District. Council of the Holmes Safety Association, which operates in the Uniontown-Brownsville bituminous coal district of western Pennsylvania will be of interest to all who are striving to increase safety in mines, quarries, and in the oil fields. The Joseph A. Holmes Safety Association The Joseph A. Holmes, Safety Association' was organized in 1916 by 24 of the leading technical societies and mining organizations to perpetuate 'the memory of Dr. Joseph Austin Holmes, first Director of the United States Bureau of Mines.

Jan 1, 1929

This report is the first in a "final" series of publications on the Juneau Mining District (JMD). This volume summarizes the results of Bureau of Mines (Bureau) investigations in the JMD during the period 1984-1988. Volume 2 consists of a detailed description of Bureau investigations of mineral de-posits, prospects, and occurrences. Volume 3 is a report on industrial minerals within the district. This study has identified and examined more than 300 mines, prospects, and occurrences containing gold, silver, copper, zinc, lead, nickel, cobalt, tungsten, molybdenum, chromium, and PGM. More than 20 of these were discovered during this study. An additional 20 prospects not mentioned in the literature were rediscovered during the JMD study.

Jan 1, 2012

By Zabetakis M. G.

This Bureau of Mines report presents a brief summary of the explosion trends in United States coal mines for the past 160 years. These trends show that in spite of the overall improvements in mine safety, the number of fatalities from ignitions of methane has actually increased in recent years. Suggestions are made of procedures that can be utilized to reverse this trend.

Jan 1, 1973

By F. A. Skirvin

Purification techniques were investigated for removing low-level metallic impurities from tungsten hexachloride. These techniques included distillation) fused-salt scrubbing) zone refining) and adsorption. Fractional distillation of tungsten hexachloride was found to be an effective purification method. The impurity levels of molybdenum) iron) nickel) copper) magnesium) and manganese were reduced to provide a tungsten halide sample which contained a total of less than 10 ppm detectable metallic impurities. Purification by fused-salt scrubbing of tungsten hexachloride in a lithium chloride-potassium chloride eutectic produced a hexachloride product which was of approximately the same quality as that obtained by distillation. Zone refining and adsorption did not appear to be as effective as distillation or fused-salt scrubbing.

Jan 1, 1967

By W. H. Tomlinson

Although the thoughts and efforts of the great majority of people in many parts of the world are today directed toward killing each other, the purpose of this paper is to discuss means of conserving human life. In a world of turmoil and strife, we find time to discuss and make plans to achieve our objective -prevention of the "sacrifice" of life through avoidable accidents. The word" sacrifice" is used here advisedly, as one meaning of the word given in the 1942 edition of Funk and Wagnalls New Dictionary of the English Language is "the act of giving up some desired or valued object for the sake of *** future good." As everyone agrees that life is man's most priceless possession, one wonders if past sacrifices have been in vain. It appears that life is cheap in America; it is cheap because some of the industrialists are too much concerned with making a profit to devote much time and thought to conserving human life; it is cheap because some labor leaders apparently are interested solely in personal power and prestige; it is cheap because a great many workmen fail or refuse to cooperate energetically with the various organizations interested ill; their safety and welfare; it is of little value because, individually and collectively, we are indifferent to our responsibilities toward our fellow men.

Jan 1, 1944

By E. P. Hayes

This report supplements the date contained in Bureau of Mines Information Circular 6156, "Special features of core drilling in the salt beds of Western Texas and New Mexico," by J. S. Wroth. That circular dealt with the drilling of the first 12 of the 24 potash tests made by the U. S. Bureau of Mines in cooperation with the U. S. Geological Survey; this report is concerned with the drilling of the last 12 tests. ACKNOWLEDGMENTS The writer is indebted to R. E. Heithecker, the Bureau of Mines engineer who had charge of the drilling of tests 13 to 17, for his well-prepared records on the drilling of these tests.

Jan 1, 1933

By Margaret E. Egan

Reliable fire detection is essential for both safe evacuation and containment or extinguishment. In order to increase reliability by reducing the number of nuisance fire alarms in underground mines that use diesel-powered equipment, the U.S. Bureau of Mines has developed a diesel-discriminating fire detector (DDD). It was designed to discriminate between smoke produced by a fire and the smoke-laden exhaust of a diesel engine. Experiments were conducted by the Bureau to compare the smoke detection capabilities of the DDD with those of conventional fire detectors in response to smoldering coal and conveyor belting. A comparison was made among the alarm times of a carbon monoxide (CO) detector with an alarm threshold of 5 ppm, a smoke detector with an optical density alarm threshold of 0.044 of', and the DDD with an alarm threshold of 0.025 V. The results show that the DDD will reliably detect developing coal and conveyor belt fires. The average time delay separating the DDD alarm from the first detector to alarm was 76 s for smoldering conveyor belt and 65 s for smoldering coal. The longest time delay between the response of the DDD and the first detector to alarm was approximately 120 s.

Jan 1, 1993

By Will H. Coghill, Fred D. DeVaney

"INTRODUCTION The Mesabi iron district of Minnesota has a potential production of over 50 million tons of iron ore annually. The large shipments of ore each year are gradually depleting the reserves, and if the present rate of production is to be maintained there must be a growth in the present available ore supply.Growth is a natural course. The growth of a city may be affected by the addition of city blocks or by the improvement of utilities necessary for its betterment, these may go on in the order named or concurrently. The city-block type of growth of the Mesabi has been tremendous, and the ""betterment"" type has followed in due course. Probably the former has reached its limit, and if so, more time will be allotted to the latter. It is not the intent of this paper to present either a eulogy of the wonderful mining methods or a history of the milling, but it is pertinent to say that if the lean-ore area continues to produce, the continuance will be more the result of further improvement of milling methods now well under way than of extension of boundaries by the city block plan of growth.In an examination of the western end of the Mesabi district one finds sludge basins containing millions of tons of millable ore rejected by washing plants which were built for economy in operating cost and with little thought of conservation, and rich tailings piles of jigging plant rejects. In addition, there is an appreciable tonnage of bawl rake pro-ducts so low-grade that it requires mixing with the best ore of the district to make it merchantable.Any of these three products is a source of additional reserves, but gangue must be removed before the products will comply with blast-furnace stipulations. All investigators are agreed that to effect this separation comminution must be fine enough for liberation, but beyond this point opinions diverge; some would seek new processes, while others adhere to methods and machines developed in other mining districts.In the investigation by the Mississippi Valley Experiment Station of the United States Bureau of Mines working in conjunction with the Missouri School of Mines and Metallurgy,Rolla, Mo., the latter course has been followed. Attention was first given to the sludge basins mentioned. From their contents good grades of concentrates were made and the results published 4 later commercial-scale tests were made in a pilot plant of 10 tables, and the laboratory results were confirmed, The tailings from jigging plants are high in iron, and a study of their possible retreatment showed that if they are recrushed, high recoveries of acceptable grade may be expected. The results will be published later."

Apr 1, 1932

By Lewis M. McNay

Description of methods employed and cost data are given for surface-mined land reclamation in Moraine State Park, Butler County, Pa. This project was conducted under the authority of the Appalachian Regional Development Act; a total of 177 acres of land was rehabilitated for specific land use purposes. The use of large equipment expedited the project work, and similar results could be anticipated on similar reclamation programs.

Jan 1, 1970

By John H. Thompson

Recent studies ** at the Pittsburgh Experiment Station of the Bureau of Mines have revealed some interesting facts as to the probable behavior of steamed coke in the blast furnace . The literature on the chemistry of the blast furnace was tho roughly reviewed , and with this information in mind , the probable behavior of the coke sulphur in the blast furnace was deduced . Enough small - scale tests were conducted to furnish a check on most of the important deductions , and the conclusions derived therefrom accord with what is already known in regard to the forms of sulphur in coke , and fit in well with the general opinion concerning blast-furnace reactions .

Aug 1, 1923

A revolutionary development in blasting materials has occurred in recent years. Ammonium nitrate, sensitized by the addition of a small percentage of No. (class) 2 diesel fuel or other suitable petroleum product, has been adopted as a low-cost, efficient blasting agent2 in a wide variety of mining, quarrying, and heavy construction operations. Moreover, the ready availability of the component supplies throughout the Nation, together with the ease of formulating them into effective blasting agents, has made it possible for the blaster himself to prepare the mixes at the site of use. Recently, most established explosives manufacturers have begun supplying premixed AN-FO (ammonium nitrate-fuel oil) or a comparable product to various mining operations. However, many individuals and small business establishments are marketing premixed products prepared in facilities that are often poorly constructed and poorly located. Although these blasting agents have partly or wholly displaced explosives such as dynamites in many applications, there are some blasting operations in which the fuel-sensitized ammonium nitrate agents do not appear to be well adapted. As long as the hazards they present are clearly understood and respected, ammonium nitrate-based blasting agents have important safety characteristics when prepared under competent factory control or field-mixed under equivalent close control. This publication attempts to summarize the knowledge of those hazards and to incorporate practical ways to cope with them.

Jan 1, 1963

By Harold E. Heide

Although the United States has been the largest consumer of tin, only a small quantity of tin was produced or. the North American Continent during peace times, and thy deficiency was made UP by foreign imports. Because the most important sources of tin wore cut off by the war with Japan, it became necessary to increase imports from South America and Africa and, if possible, develop domestic tin reserves. Most of the tin produced in North America has come from the Seward Peninsula, Alaska, and a substantial portion of this was produced from the Potato Mountain area. Tin was first identified as occurring in the Seward Peninsula by A. H. Brooks in 1900, when a part of heavy concentrates from Anikovik River and Buhna Creek, one of its tributaries, proved to be stream tin. 4/ His report was given considerable publicity by the daily press, and the first steamers north in 1901 carried a number of prospectors bound for the Seward Peninsula to search for tin. The deposits of stream tin on Buck Creek in the Potato Mountain area were discovered in the fall of 1901. 2/

Jan 1, 1949

By James H. Cobbs

The purpose of this study is to investigate the application of boring equipment to the production of anthracite coal from steeply pitching beds. Both raise boring and augering equipment were considered. Previous studies (11) have indicated that boring equipment may have definite applications to the development of steeply pitching anthracite beds. This investigation was to carry forward previous work to determine the possible application of the two different types of equipment being considered. Previous conclusions have been substantiated by the results of this study.

Jan 1, 1975

By J. Pasini

The Bureau of Mines has investigated novel methods of stimulating petroleum production from reservoirs in the Appalachian Region. An important consideration in applying stimulative production methods is the control and removal of solid precipitates from the boreholes of production wells. Where paraffin-base crude oils are produced, as in the Appalachian Region, the accumulation of paraffin may be particularly troublesome. Paraffin deposition is a major production problem that has confronted the petroleum industry for many years. Although considerable effort has been expended by industry and government, a suitable solution has not been found because of the individuality and complex nature of the deposits. Remedial methods used to prevent or remove paraffin fall generally into four classes: (1) Chemical, (2) physical, (3) operative, and (4) combination. Each class has many subclasses that apply to particular problems in different oil- producing areas. Recently, chemical inhibitors and the sonic pump have assisted operators in preventing and removing paraffin deposits. Because these methods are relatively new, their degree of application has not been completely evaluated.

Jan 1, 1963

By Kenneth M. Earl

This report describes the results of a field study conducted by the Bureau of Mines during 1956 and 1957 on manganese-and iron-bearing mineral deposits in the southern district of Aroostook County, Maine. The work was undertaken to determine the extent of deposits largely concealed under glacial drift and to obtain subsurface samples for manganese mineral identification and research in ore dressing and extractive metallurgy. The investigation was confined to the Westford Hill-Daggett Hill area in Hodgdon Township and to the Stewart prospects and vicinity in Linneus Township. Over 50 magnetic anomalies were mapped by magnetometric surveys in the Westford Hill-Daggett Hill area, Hodgdon Township. The largest anomaly, as outlined by the 1,000-gamma contour, indicates a deposit 3,200 feet long with a maximum width of 350 feet. The smallest anomaly measures about 10 feet wide by 25 feet long.

Jan 1, 1962

By J. W. Town

As part of the Federal Bureau of Mines titanium resources examination program, samples from seven deposits in the Pacific Northwest were tested for amenability to various beneficiation techniques. The samples obtained by the Bureau's Office of Mineral Resources at Spokane, Washington represent a large potential source of titanium. This report summarizes the results of tests at the Bureau's Metallurgy Research Center, Albany, Oregon. Recoveries from tabling placer samples were about 50 percent at grades of 30 percent titanium dioxide. Flotation was the most effective method for concentrating the fine ilmenite in clay samples; recoveries of approximately 50 30 percent titanium dioxide. Flotation was the most effective method for concentrating the fine ilmenite in clay samples; recoveries of approximately 50

Jan 1, 1961

By Jos. R. Guiteras

This paper is one of a series describing; mining and milling methods and costs being published by the Bureau of Mines. It deals with the mineral resources of western South Dakota and describes the mining and milling of tantalite and associated amblygonite by the Black Hills Tin Co. and the Fansteel Mining Corporation. ACKNOWLEDMENTS Acknowledgment is made to Earl C. Schultz and Arthur I. Johnson, respectively superintendent and engineer for both the Black Hills Tin Co. and the Fansteel Mining Corporation, who contributed the information on mining and milling operations.

Jan 1, 1939