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By Fred N. Kissell

This handbook describes effective methods for the control of mineral dusts in mines and tunnels. It assumes the reader is familiar with mining. The first chapter deals solely with dust control methods, regardless of the application. It is a brief tutorial on mining dust control and will be of help to the reader whose dust control problem does not conveniently fit any of the mining equipment niches described in later chapters. The subsequent chapters describe dust control methods for different kinds of mines and mining equipment. This includes underground coal and hard-rock mines, as well as surface mines, stone mines, and hard-rock tunnels. Because dust sampling has so many pitfalls, a chapter on methods used to sample dust is included. For those occasions when there is no practical engineering control, a chapter on respirators is also included. Except for those listed as ?future possibilities? in the longwall chapter, the dust control methods described are practical and cost-effective for most mine operators. If controlling dust were a simple matter, dust problems in tunnels and mines would have been eradicated years ago. Unfortunately, most underground dust control methods yield only 25% to 50% reductions in respirable-sized dust. Often, 25% to 50% reductions are not enough to achieve compliance with dust standards. Thus, mine operators must use several methods simultaneously, usually without knowing for sure how well any individual method is working. In fact, given a 25% error in dust sampling and day-to-day variations in dust generation of 50% or more, certainty about which control methods are most effective can be wanting. Nevertheless, over the years, some consensus has emerged on the best dust control practices. This handbook summarizes those practices.

Jan 1, 2003

By D. B. Taliaferro

[Recovery of core specimens from subsurface formations and their subsequent analysis are important aids in efficient development and operation of oil and gas fields. Core specimen first were obtained mainly for the geologic information they revealed; now they are on analyzed to determine many of the physical characteristics and conditions of the subsurface formations as well. Cores recovered from the producing formations may be analyzed for porosity, permeability, oil content, "connate" water content, and other physical and chemical properties of the formation, all to the end of furnishing enough data for making reliable estimates of the quantity and availability of oil and gas within reservoir and in devising efficient means for their withdrawal.]

Jan 1, 1939

By R. S. Dean

This is the fourth of a series; of annual report of the Metallurgical Division to be released in this form and cover the fiscal year July 1, 1937, to rune 30, 1938. This report is not merely a recitation or brief of the year's work; it contains technical information in usable form, although a some of this has appeared or will he issued in greater detail in separate reports. The table of contents that follows fists the principal investigations accomplished and those that are being continued. Other projects are being begun and contemplated for the next year.

Jan 1, 1938

By Margaret R. Egan

A study of the combustion emission products of rigid ventilation ducting was completed by the U.S. Bureau of Mines. The ducting was composed of fiberglass-reinforced polyester resin. Four properties of the ducting were evaluated: (1) propensity to ignite, (2) smoke characteristics, (3) gas emissions, and (4) heat release. Particle sizes, obscuration, optical densities, and production constants for gas and smoke were also calculated. These results provide comprehensive data about the emission products, detectability, and relative hazards of fiberglass-reinforced plastic ducting and other mine combustibles under realistic fire conditions.

Jan 1, 1990

By Leland H. Johnson, D. O. Kennedy, John Hyvarenen

"SUMMARYA chronological list of accidents at metal and nonmetal mines and quarries (excluding coal mines) in the United States in which five or more lives were lost has been compiled. Many accidents were described in more detail because of their unusual features. Tables have been included to indicate the number of major disasters and fatalities by the principal product mined, by State, and by 10-year intervals prior to 1945. The number of men employed to indicate man-hours exposed is unavailable; therefore, a true picture of disaster data by principal product mined, by State, and by 10-year intervals is not possible. However, the data are presented to indicate the causes of major accidents and bring to the attention of those affiliated with metal and nonmetal mines and quarries the hazards involved and lessons that can be practiced to keep such accidents at a minimum.INTRODUCTIONThe Bureau of Mines was requested to compile a chronological list of accidents at metal and nonmetal mines and quarries (excluding coal mines) in the United States in which five or more lives were lost. Data have been assembled on accidents from all causes in these mines and quarries from the earliest available information (describ¬ing an underground mine fire in Nevada in 1869) to the last reported major accident (a fire at a company-owned bunkhouse in Arizona in 1945).The accounts of the accidents were taken from articles in the technical press and from published and unpublished reports of the Bureau of Mines. Many of the accidents have been selected for more detailed descriptions because of the unique circumstances and to show the variety of dangers involved.Tables are included to indicate the number of major accidents, with resultant fatalities, by the principal metal and nonmetal producing groups, by State, and by 10-year intervals previous to 1945. The interval 1869-1875 does not cover a 10-year span because of incomplete records previous to 1869.ACKNOWLEDGMENTSThe information contained in this report was obtained from the Engineering and Mining Journal from 1874 to 1947, the Mining and Scientific Press from 1908 through 1922, from various published and unpublished reports of the Bureau of Mines and from reports by State departments of mines. Daniel Harrington, retired chief of the Health and Safety Division; E. H. Denny, supervising engineer, District H; R. M. Loucks, mining engineer; and other engineers of the Division contributed much valuable information and assisted materially in the study."

Apr 1, 1949

By James L. Elder

Field-scale experiments were conducted at Gorgas, Ala., from 1951 to 1954. Three reaction paths were formed by electrolinking-carbonization, using electrode spacings of 150, 152, and 155 feet. The coal along these reaction paths was gasified, using air, oxygen, and steam separately or in various combinations. At the conclusion of operation, a drilling survey was conducted to determine the location and approximate area of the reaction zones. During the applications of the electrolinking-carbonization technique the maximum limitation on electrode spacing was not determined. Initial tests were conducted at 60-foot spacing. Successful path-preparation tests were made at 150-, 152-, and 155-foot spacings, and the indications were that much longer spacings were possible. The potential requirements appear to be constant, regardless of path length, while the gross power required probably will increase with path length. During the carbonization phase gas was produced that is similar in quality to coke-oven gas produced at low to intermediate temperatures.

Jan 1, 1957

By A. W. Deurbrouck

This report describes the washability characteristics of 18 coal samples taken from 11 drill hole cores from the San Juan Basin area of New Mexico and Colorado. The ash content of these coals could generally be substantially reduced by removing the heavy impurities. The coals were characteristically low in sulfur content; only one sample contained more than 1 percent sulfur after removing the sink-I.50 specific gravity material. The coals ranged in rank from subbituminous C to high volatile C; 11 of the samples were subbituminous A. Many of these core samples came from areas where very little fieldwork has been done; consequently, an outgrowth of this work has been an increase in known coal reserves of the San Juan Basin area.

Jan 1, 1972

By James C. Cawley

The Bureau of Mines conducted an investigation to statistically determine the mean current or voltage for resistive, inductive, and capaci-tive circuits that would cause spark ignitions in 8.3% methane-air, 5.3% propane-air, and 7.8% ethylene-air mixtures. Each mean ignition current or voltage was determined on the basis of 100 trials. Each trial consisted of 400 revolutions, 200 in each polarity, at 80 rpm of the standard breakf1ash apparatus. In general, spark ignition curves published in UL 913 for resistive and inductive circuits represent approximately the mean current values determined in this study, while published capacitive circuit values in methane are considerably less than the mean voltage values from this study, especially for a capacitance of less than 100 ~F. For resistive and inductive circuits, spark ignitions were obtained at currents con-siderably below those in the published curves, but this study was not optimized to find minimum ignition values. This report defines "safety factor" as applied to intrinsic safety testing as the energy ratio of the mean values of ignition current or voltage for two test gases. The safety factors presented in this report are not constant with voltage or current and, therefore, are not recommended for use.

Jan 1, 1986

By Bernard J. Steblay

The U.S. Bureau of Mines has attempted to use ultrasonic signal travel-time measurements to measure loaded roof bolt strains. The strain measurements are then related to roof bolt loads through equations or empirical calibrations. Such techniques offer the potential of accurate, rapid bolt load measurement that does not disturb the anchotage. This report presents 6e research findings for a specific type of ultrasonic measurement instrument using a pulsed-phase-Iock-Ioop technique. This technique measures signal travel time indirectly by measuring frequency changes. A complete development of the applicable theory and detailed derivations of key equations is presented along with empirical laboratory and field results. The differences between anticipated and measured behaviors are analyzed and discussed. The report identifies problems encountered in applying pulsed-phase-Iock-Ioop technology to roof bolt load measurement and provides potential solutions to many of them. A key assumption of pulsed-phase-lock-loop theory is that driving and reflected signal frequencies will always be equal. Findings showed that not only were actual frequencies not equal but they were not stable or simply related. Reflection wave shape also was not stable. The ramification of these findings and ways to minimize their adverse effects are presented.

Jan 1, 1990

By Clayton M. Rumsey

In 1984, the U.S. Bureau of Mines conducted a mineral survey of a 26,598-acre study area which includes the 23,702-acre Mt. Limbo Wilderness Study Area (NV-020-201). The study area is 65 miles northeast of Reno, NV, and is underlain mainly by Cretaceous granodiorite that comprises the Selenite Range. Tertiary basalt, rhyolite, and sedimentary rock as well as Quaternary alluvium and lake deposits are exposed near the study area boundary. Mines just north of the area in the Hooker mining district produced tungsten ore in the 1940's and 1950?s. Similar deposits are not known in the study area. Disseminated gold is in sinter about 6 miles west of the study area and at several other locations regionally.

Jan 1, 1986

By Richard L. D?Arcy

This paper describing the mining practice and methods at the United Verde Extension mine, Jerome, Ariz., is one of a series of papers in preparation by the Bureau of Mines presenting the mining methods used in various mining districts of the United States. The United Verde Extension mine is a massive, high-grade deposit of copper sulphide containing some gold and silver and is mined almost exclusively by the conventional square-set method with some local modifications. About 450 men are employed underground and 1200 tons of direct smelting ore is produced per day. Figure 1 is a surface map of the Jerome district.

Jan 1, 1930

By M. E. Tyrrell

The Bureau of Mines produced building brick of good quality in an investigation designed to explore the possible utilization of high-glass fractions of municipal incinerator residues in the manufacture of building products. Common clays, lime, and sodium silicate were used as binders for the nonplastic residues Test bricks were formed by dry-pressing, soft-mud molding, and stiff-mud extrusion. A run of standard-size face brick dry-pressed and fired in the West Virginia University Coal Research Bureau pilot plant demonstrated that SW-grade glass-clay face brick can be produced on a commercial scale without difficulty. A cost evaluation made for production of the brick showed an estimated cost of $42.13 per thousand bricks for a shuttle kiln plant and $28.70 per thousand for a tunnel kiln plant.

Jan 1, 1972

By A. L. Worthen

This is one of a series of pacers being published by the United States Bureau of Mines, describing mining and milling methods at crushed-stone plants throughout the United States. These pacers are designed to disseminate technical information regarding the methods used. The cost tabulations represent operating expenditures only and not total production costs. Although the publication of total production cost might not be advisable in some instances, yet a knowledge of operating costs is essential to the technical discussion and study of the methods employed. The attention of the reader is specifically called o this differentiation in order that there will be no misunderstanding of the scope of the cost tabulations. This paper deals with the quarrying and crushing methods used at the Plainville plant of the New Haven Trap Rock Co., which produces annually between 275,000 and 300,000 tons of trap rock, Although pct the largest quarry operated by the company, it typifies the standard methods used by all the quarries in producing crushed stone and has one or two rather unique operating features. The cost of production at this plant is close to the average cost at all quarries of the company.

Jan 1, 1936

By K. E. Stanfield

Oil-yield results are presented for 65 oil-shale sections in Piceance Creek Basin, Colorado, sampled during the period 1957 through 1963. Including previously published data, oil-yield results for 203 sampled sections have now been released by the Bureau of Mines to aid in appraising the shale oil potential of the basin. Oil yields of core samples (135 sets) were regarded as reliable bases for appraising the Mahogany-zone interval, but only 5 sets of cores sampled the deeper, lower-zone oil shales. Drill cuttings (68 sets) sampled the lower-zone oil shales, but their oil yields are principally indicative and should be confirmed by analyses of cores. More complete core sampling of the lower-zone oil shales is needed.

Jan 1, 1967

By Lijun Xu, Jan M. Mutmansky

"Mutmansky, J.M. and· Lijun Xu, 1989. Some observations on particulates collected in underground coal mines using diesel and non-diesel equipment. Min. Sci. Technol., 9: 207-218.The results obtained when sampling twenty underground coal mine sections, each in a different mine, are outlined. The sampling effort was oriented toward a detailed characterization of coal mine dusts and thus eight-stage Anderson Model 298 impactors were used as the primary collection instrument. This instrument allowed a fairly detailed size distribution for each of the particulates sampled. Because four of the mines used diesel outby equipment and/or diesel shuttle cars at the face, it is possible to make some comparisons of the particulate distributions in diesel versus non-diesel mines.One of the more interesting results is the pattern that exists in mines lising diesels only for outby utility haulage. Particulates in these mines seem to be consistently heavy in the fine size ranges, perhaps being of significant concern to the industry. While no definite conclusions can be drawn from the limited data, a more detailed study of particulates may provide a better picture of particulate loadings.IntroductionThe subject of particulate emiss1ons from underground diesel equipment is currently a very important topic as health concerns and regulation of diesel particulate emissions have created new environmental problems for mine operators. The amount of particulate matter originating from diesels has not been extensively measured and problems of differentiating coal and mineral dust from diesel particulates make existing data questionable.However, it is necessary to make an assessment of the problem in order to solve it. It is known that particulates from diesel engines are solid aerosols formed in the combustion process. Technically, this places the particles in the category of fumes. It is also known from tests where no mineral dust could be a factor in the measurements that about 90% of diesel particles are less than 1 µm in aerodynamic diameter [3]. To measure the diesel component of a coal/diesel particulate to measure, Johnson et al. [2] have developed procedures for utilizing laser Raman spectroscopy. The determination of diesel content in a coal/diesel mixture is difficult due to the chemical similarity of the two organic materials. However, laser Raman spectroscopy, which is often used for identification of organic materials, has potential if the Raman spectra for the two materials are different and unique. The study concluded that an accuracy of ±~% could be achieved for mixtures containing up to 55% diesel particulate. The method is relatively complex and would need further development for routine application."

Jan 1, 1990

By Irving Hartmann

Falls of roof in coal mines and means of preventing them have been subjects of study for many years, and an extensive literature has resulted. Usually each individual paper has placed emphasis on one phase of the subject, such as fatalities, nature and extent of nonfatal injuries, methods of tembering (particularly in rooms or other wide places), safety along retreating rib lines, and methods of causing falls in abandoned areas. It is only in recent years that there has been persistent question as to why

Jan 1, 1941

By M. J. Gavin

Within the past three years numerous inquiries for information on oil shale have been received by the Bureau of Manes. These inquiries have been increasing to such an extent that it has seemed advisable to issue a short paper prior to the publication of a bulletin on the subject, giving a, general discussion of the subject and a comprehensive list of references, so that those interested in the details of obtaining oil from shale can find additional information without much difficulty. Some of those who desire information are interested only in a general discussion of the subject, or are not in a position to refer to books and' articles describing the industry. The material for this paper is largely derived from published information on oil shale. Much of the information is obtained-from the books and articles mentioned in the list of references, and has been compiled with the intent of furnishing information to those not interested in all the details.

Jan 1, 1921

Surface mining and reclamation of a southeastern Ohio site with sandstone-shale overburden resulted in (as compared to premining levels): 1) runoff volumes and peak rates that increased by a factor of from 2 to 10 during mining and after reclamation, 2) destruction of the "aquifer" perched on the underclay of the mined coal bed and gradual, but, as yet incomplete redevelopment of this aquifer after reclamation, 3) no immediate effect on another, lower perched "aquifer", 4) up to 100 times greater sediment concentrations in runoff. Results were influenced by increasing annual precipitation amounts through the period of record; 1978, 1979, and 1980 (postreclamation years) experienced precipitation amounts approaching or exceeding long-term normalcy for the area. Part of the reason that the site produced more runoff after reclamation than before mining is that the premine condition was one of an open, porous soil under woodland, while the postreclamation condition was one of a compacted, bulldozed soil. Sediment concentration results were influenced by failure of the postreclamation erosion control system and by a series of detention reservoirs above the stream monitoring station.

Jan 1, 1983

By Albert E. Schreck

[THE COMPOUNDS of strontium were confused with those of barium until 1790, when A. Crawford discovered that the mineral strontianite, long believed to be a barium mineral, was a compound of a new element. This discovery was confirmed 2 years later by I. C. Hope. The mineral was named strontianite because it was found near the town of Strontian in Argyllshire, Scotland. In 1808 Sir Humphrey Davy isolated strontium metal by the electrolysis of fused chlorides. Celestite (strontium sulfate) and strontianite (strontium carbonate) are the principal strontium minerals. Because of its more widespread occurrence, celestite is more important commercially.]

Jan 1, 1959

By W. W. Adams

"The National Safety Competition of 1930, the seventh annual contest conducted by the United States Bureau of Mines to promote safety in the mines and quarries of the United States, has been concluded, and the five winners of the bronze trophies, The Sentinels of Safety,' which are provided by the Explosives Engineer magazine and awarded annually for the most excellent safety records, have been determined by the committee of award. One trophy was awarded to an anthracite mine in Pennsylvania, one to a bituminous coal mine in the same State, one to an iron-ore mine in Michigan one to a gypsum mine in Ohio, and one to an iron-ore opencut mine in Michigan.These trophies were awarded to the companies for having the smallest loss of time from accidents in proportion to the total number of man-hours worked by all employees at their mine or quarry. Honorable mention was awarded to each mine or quarry that ranked second, third, fourth, or fifth in its own ground and to all plants that were operated without a lost-time accident during the contest year. Eighty-four out of 337 plants that competed for the trophies were operated without an accident that disabled an employee beyond the day on which the accident occurred.Under the contest rules, all mines and quarries were divided into five groups, four of the groups representing different classes of underground mining operations (anthracite, bituminous coal, metallic ore, and nonmetallic mineral), and the fifth group repre-senting the quarrying or opencut mining of minerals whether metallic or nonmetallic. Twenty-seven mines were included in the anthracite group, 68 in the bituminous group, 52 in the metal group, 24 in the nonmetallic-mine group, and 166 in the quarry and opencut-mine group. The total of 337 mines and quarries was 26 more than the number of plants that completed the contest during the previous year.The committee of award which determined the winners of the contest was composed of seven members, all known throughout the mineral industry but not connected with the United States Bureau of Mines. The committee included W. H. Cameron, managing director of the National Safety Council; William Green, president of the American Federation of Labor; James F. Callbreath, Secretary of the American Mining Congress; T. T. Read, Vinton professor of mining of Columbia University and editor of Mining and Metallurgy; C. B. Huntress, executive secretary of the National Coal Association; A. J. Curtis, assistant to the general manager of the Portland Cement Association; A. T. Goldbeck, director of the bureau of engineering of the National Crushed Stone Association."

Jun 1, 1931