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By Rena I. Geroyan

This U.S. Bureau of Mines report presents an evaluation of the coal mining industry's impact on the economy of Pike County, KY. A software package called IMPLAN was used to perform the analysis. The results of this study show that coal mining was the primary income producing industry in Pike County in 1990, accounting for about 46% of the county's Total Industry Output, and 21% of the total employment.. Coal production in that year amounted to 29.6 M mt (32.6 M st). Two alternate economic scenarios were developed to study the potential effects of changing coal market conditions on the county. Scenario A assumes market changes result in a coal production increase of 4.5 M mt/yr (5.0 M st/yr), and scenario B assumes a decrease of 4.5 M mt/yr (5.0 M st/yr). Scenario A would result in a 15.3% rise in the value of Pike County's Total Industry Output, adding a total of 1,663 jobs (+6.1%) in all sectors in the county. Scenario B would have the opposite effect, decreasing the Total Industry Output and employment by identical amounts. Such knowledge would allow local and regional officials to anticipate the economic and social impacts of shifts in coal production, and plan accordingly to mitigate impending changes.

Jan 1, 1994

By P. J. Coleman

Research in the field of mining safety and health in the United States plays an important part in protecting the lives of miners. The National Institute for Occupational Safety and Health (NIOSH) Mining Program conducts surveillance, studies and developmental work aimed at improving the safety and health of miners. With recent reviews of the Mining Program by the National Academy of Sciences and the Mining Program response (NIOSH, 2008), the importance of setting goals, conducting high quality engineering and scientific research and evaluating the outputs, outcomes, relevance and impacts of these projects has been reemphasized. Surveillance of reported injuries is a first step in deciding on research directions and in designing specific projects. Groups of injuries often share features and attributes that suggest common causes and may respond to similar preventive efforts. Identifying groups of injuries also serves to prioritize intervention efforts. The Mine Safety and Health Administration (MSHA) Accident and Injury database (MSHA, 2008) provides individual case reports of mining injuries, illnesses and certain no-injury accidents (events such as roof falls that stop mine production or miners? activities for more than one hour). This database is an indispensable resource for researchers and stakeholders needing information on the statistics of these events. From an epidemiological perspective, research projects target groups of miners at risk due to specific patterns of work, equipment, mine settings and the management of safety and health in their mines. Incidence rates are provided by the MSHA data for selected variables, such as surface/underground location, standard industrial classification and state. While incidence rates are the preferred measure for all variables, denominators are not typically available; for example, to more clearly under-stand the data about injury by occupational type, it would be necessary to conduct demographic surveys. A current survey of the demographics of the mining industry should be complete by 2010, which will allow incidence rates to be developed for a number of variables such as age, occupation and experience. This survey will provide the first update of its kind since the first survey was conducted in 1985.

Jan 1, 2010

By G. W. Marks, A. H. Roberson

"Previous investigation 4/ has demonstrated that some of the aliphatic amines are suitable absorbents for 302, This paper reports the results of physical studies of a number of such amines with the object of determining which is most favorable as an absorbent.Monoethanol amine, diethylene triamine, and triethylene tetramine appear to be the most promising of all the amines studied, and most of this report has been devoted to studies of the physical properties of their aqueous solutions, which contain varying amounts of SO2.PURITY OF MATERIALSAll of the amines used were of commercial grade, because the primary object of this research was the investigation of a proposed works process rather than the accumulation of scientific data.The aminoethyl derivitives of ethylene diamine, namely, diethylene triamine, triethylene tetramine, and tetraethylene pentamine, only recently have been produced commercially. The chemistry of aliphatic amines is complex, and these newer derivitives have not been investigated, completely. Chemically pure material is not on the market, and since definite physical standards have not been published, one could not be assured of a pure product even if the commercial material was refined.The compilation of physical constants for the pure amines would involve much time—consuming effort without materially enhancing the value of this paper, as this work was not devoted to the development of fundamental standards."

Oct 1, 1938

By C. Gary Reiness

A safety glass eyepiece which had been repeatedly exposed to mine environment over a number of years was studied to determine some of its optical properties. In the regions from 385 to 400 mµ and from 625 to 760 mµ, the transmittance was less than the 89 percent required by the American Standard Safety Code for Head, Eye, and Respiratory Protection. From 200 to 320 mµ the relative transmittance of two parts of the eyepiece was found to vary widely, having a maximum of 38 percent difference at 315 mµ. Irradiation of the glass by ultraviolet light caused enhanced absorption in the range from 200 to 1,200 mµ. There was a time-dependent increase of 1016 color centers per cubic centimeter throughout this range after 36.5 hours of irradiation. The rate-of-growth curve for the optical density, at 243.5 mµ and 23° C, was resolved into linear and saturable components, indicating zero order and first order

Jan 1, 1968

By W. T. Millar

Field reconnaissance and laboratory tests on clay from South Windsor, Hartford County, Conn., indicate that the clay is suitable for lightweight aggregate raw material. Exploration of the deposit supports the conclusion that the reserves of clay are sufficient for economical mining operations to produce lightweight aggregate. Preliminary tests indicated that the clay has a short bloating range. Initial expansion occurred at 2,000° F, and at 2,100° F the clay was slightly overfired and sticky. Rotary kiln tests verified the preliminary data, and these tests showed that the clay would make a good lightweight aggregate if the processing temperature and the kiln feed sizes were closely controlled. Lightweight concrete made from the processed aggregate had properties comparable to those of concrete made from a commercial clay aggregate.

Jan 1, 1964

By Michael R. Yenchek

The U.S. Bureau of Mines investigated the performance of portable power cables under transient conditions. This research had a twofold purpose: (1) to define the thermal characteristics of electrically overloaded trailing cables, and (2) to conceptualize electrical protection for cables that allows maximum cable efficiency without diminishing electrical safety in underground mines. Several tasks were undertaken in support of these goals during the 3-year research effort. Overload tests ranging from 2 to 12 times rated ampacity were conducted in the Bureau's Mine Electrical Laboratory. Two thermal models of energized type G-GC trailing cables were constructed, one based on thermodynamic theory and the other using empirical data from previous Bureau load tests. The empirical model was then incorporated into an interactive computer program that can assist designers and approvers of mining machines in selecting the appropriate size trailing cable. This program can be the basis for a cable protection system that ensures that cables are not the source of fires, ignitions, burns, or explosions underground.

Jan 1, 2010

By J. W. Paul

This circular is one of a series of papers4 on coal-mining methods and costs which are being prepared through the sponsorship of the U. S. Bureau of Mines for the purpose of presenting information on present mining methods and certain features which govern costs, safety, and conservation. The methods employed are influenced by natural local conditions with respect to the thickness, character, and dip of the coal bed, the nature of the roof and thickness of the overbearing strata, and the means employed for roof support and its control.

Jan 1, 1929

By Albert E. Keller

This paper describing the timekeeping and pay-roll methods of the Britannia raining and Smelting Co. (Ltd.) is one of a series being prepared for and published by the United States Bureau of nines regarding office procedures in connection with mining operations. The general office of the Britannia Mining and Smelting Co. (Ltd.) is located at Britannia Beach, B. C., a town of about 600 inhabitants at tidewater on the east side of Howe Sound and about 30 miles from Vancouver, B. C. The Beach, as it is locally termed, is a company town consisting largely of about 250 employees of the company and their families. Here is the milling and concentrating plant of over 6,000 tons daily capacity- the main service units comprising the electrical, mechanical, blacksmith and woodworking shops and the local electric-furnace foundry; the central-heating steam plant; the air and electric generating units; the ball-manufacturing plant; the warehouses; and the general store, which serves this community and also acts as distributor for the general stores located elsewhere on the property.

Jan 1, 1932

By Ronald T. Mayerle

In 1989, the U.S. Bureau of Mines conducted a mineral investigation of the Mallard study area near Elk City, Idaho. The study area comprises most of the original Mallard RARE II area (1-847) plus some additional lands. The investigation is part of an ongoing, multi-year study of north-central Idaho that is being conducted in cooperation with the Idaho Geological Survey and the U.S. Geological Survey (USGS). The only identified resources are rock suitable for road metal. Five lode prospects and a pyrite-bearing rock quarry, which is operated by the Forest Service for aggregate, were examined for metals. One of the prospects warrants additional exploration for silver in quartz veins, but the chance of finding an economically minable deposit is limited. Several rock and stream sediment samples were anomalous in various metals. Two of the more promising localities for gold and/or other metals are adjacent to a unit of the Frank Church-River of No Return Wilderness that the USGS classified as having a moderate potential for gold deposits related to fossil hot springs.

Jan 1, 1991

By E. R. Cole

The Bureau of Mines developed a procedure that enables substitution of zinc cathodes for the aluminum cathodes normally used in commercial zinc electro-winning. Using zinc cathodes eliminates the necessity for stripping and makes it possible to electrowin zinc from solutions derived from material containing excessive amounts of soluble fluorides; for example, zinc concentrates obtained as a byproduct of fluorspar mining in Kentucky and Illinois. To demonstrate the viability of using zinc cathodes, fluoride-containing zinc concentrate was roasted, leached, and purified according to current commercial practice. Electrolysis was carried out in 0.8-, 1-, 5, and 10-liter cells at 35° to 40° C with a cathode-current density of 8 amp/dm2 in a solution containing 65 g/l Zn++ and 200 g/l H2S04 using PbO2 anodes. Zinc deposits were produced on zinc cathodes with good morphology and excellent current efficiency (90 to 94 pct) in solutions containing enough fluoride (~0.5 g/l, F+) to cause sticking of zinc to aluminum cathodes. The approach described has failed previously because of severe solution-level corrosion of the zinc cathodes. The present investigation found that the use of a simple mechanical barrier to prevent oxygen migration from the anode was sufficient to prevent solution-level corrosion of the zinc cathode starting sheet.

Jan 1, 1979

By Howard C. Pettibone

Mine safety personnel reported occurrences of excessive "glove-fingering" and other problems with resin-grouted roof bolt installa tions. To study these problems, the Bureau of Mines designed a test plan to (1) obtain baseline information on several resin cartridges and (2) investigate the variables involved in the installation of a resin bolt. Three brands of resin representative of the industry in January 1983 were selected for cartridge evaluation. The installation variables selected for study were the method of installation, the hole depth, and the hole annulus. These variables were studied by installing a series of bolts in concrete blocks using different values for each variable. Results of the research show overspinning the resin may cause problems, but they can be avoided by using the spin times recommended by manufac-turers. Excessive glove-fingering is not a problem if the manufacturer-recommended installation procedures are followed.

Jan 1, 1987

By L. F. Heising

The Bureau of Mines evaluated 191 composites from the central Mesabi Range, Minn., chiefly by reductive roasting and magnetic separation. After reductive roasting and magnetic separation at minus 325 mesh, 28 composites produced concentrates that contained an average of 66.0 percent iron with less than 10 percent silica. Recovery of contained iron was over 90 percent. Natural magnetic material in excess of 5 percent was present in 142 composites. Trial flotation tests were used to evaluate three samples unresponsive to reductive roasting and magnetic separation procedures, and satisfactory concentrates having low silica contents (averaging 6.6 percent) were achieved.

Jan 1, 1965

By R. T. Artz, Simpson. O. V.

"INTRODUCTION The provision of escapeways from coal mines is a moral and, in most States, a legal obligation of mine owners and operators. The obligation is not always fulfilled because of the hope that no occasion will ever arise requiring the use of such facilities, and, as time passes without the need for using them, a false sense of security is born in the belief that ""it can't happen here.""The disastrous fire in a mine in Ohio on July 5, 1944, again focused attention on the importance of escapeways in averting disasters and made it clear that one or more dependable exits must be provided from a mine and parts thereof where men might be trapped by being cut off from the regular travel route. This matter of always-having available travelable exits has been advocated for many years by the United States Bureau of Mines."

Aug 1, 1948

By D. Harrington, R. R. Sayers

For several years the writers have been studying various phases of the effect of air conditions in metal mines upon underground workers ; in 1918 a short study was made in certain hot and deep mines and brief reports were issued in the Engineering and Mining Journal ( August , 1920) and in the U. S. Public Health Reports (Vol . 36 , No. 4 , January 28 , 1921 ) . In 1921 a more extended study was made (also in hot and deep metel mines ) with intent to determine the limiting conditions imposed upon underground workers by the physiological effect of various air movements , temperatures , and humidities , with and without work . It is the purpose to publish a series of short papers on this later investigation , each paper to consider one particular phase of the work . The present paper deals with the effect on body temperature and pulse rate in still air as compared with moving air of temperatures from 90 to 100° F . and 100 per cent relative humidity, the subjects at rest .

Apr 1, 1923

By Seth C. Schaefer

The Bureau of Mines investigated the standard Gibbs energies of forma-tion AGfo, for NiCr204 (nickel chromite) and CoCr204 (cobalt chromite). High temperature galvanic cells employing stabilized ZrOz (zirconia) as the solid electrolyte were used to measure the open-circuit potentials for the cell reactions ?

Jan 1, 1986

By C. F. Wingquist

As part of an ongoing study to determine how the wear of mining tools affects dust generation, the Bureau of Mines has measured bit tempera-ture rise during cutting of abrasive rock. Radial bit wear-flat tem-peratures generated by linear cutting in Berea Sandstone were measured as a function of cutting depth and speed. Depths of cut (DOC) were 1/8, 1/4, and 1/2 in, and cutting speeds were 10, 40, and 80 in/s, respectively. Temperature sensing was accomplished by emplacement of a miniature thermocouple into the center of the wear flat. Temperatures observed ranged from 2000 to 5000 C. Correlation between depth and temperature was weak. Temperature increased linearly with speed at 1/2-in DOC, but data taken at 1/8-and 1/4-in DOC produced inconclusive results. The results indicated that at least for deeper cuts (1/2 in), bit temperature, and therefore wear, can be reduced by lowering the cutting speed.

Jan 1, 1987

By H. P. Rue

The Bureau of Mines has recently collected two samples of crude oil from wells in the Greasewood Flat, area of northeastern Colorado. Sample 31310 was taken from the Continental Oi1 Co.'s well Briggs No. 1 which came in on September 27,7.931, with a maximum production of 940 barrels per day. Sample 31311 was taken from the Reiter-Foster Oil Co.'s well Ida Johnson No. 1 which came in on August 24, 1931 with a maximum production of approximately 1000 barrels per day. These two samples of crude oil are typical "intermediate base" crude oils according to the classification defined by Smith and Lane. The characteristics of these two samples, as shown by the Hempel analyses, indicate that they are almost identical. They have a very low sulphur content, and the residuum has a low carbon-residue content which would indicate that they are excellent crude oils for refining. Crude oils yielding a residuum which has a carbon-residue content of 4 per cent or less usually make good material for the manufacture of cylinder stocks. The pour points of the samples and the cloud test of the fractions obtained from the vacuum distillation indicate that the Greasewood Flat oil contains considerable wax. The high wax content would cause some difficulty in transmitting this oil through a pipe fine during extreme cold weather.

Jan 1, 1932

By Stephan Stecura

One of the principal objectives of the Bureau of Mines program for development of superrefractory ceramic materials is to obtain fundamental data on the physical properties of refractory oxides. Elements of particular interest to research workers in the Bureau include groups III and IV of the Periodic Table and the rare-earth group. This report contains thermal expansion and phase inversion measurements on oxides of scandium, yttrium, lanthanum and 12 lanthanide series elements (promethium and terbium omitted) up to 1,350°C, made by high-temperature X-ray diffractometer techniques. Thermal expansion values were calculated from unit cell dimensions measured at selected temperatures; with anisotropic oxides expansion was determined parallel to each major crystallographic axis. The combined random and systematic errors in the thermal expansion values are considered to be less than 3 percent of the total expansion at 500° C, and approximately 2 percent at 1,000° C, No difference in expansion coefficients was observed between heating and cooling cycles for oxides that did not undergo phase inversion. Tabular data of linear expansion, in percent, linear expansion coefficients, and graphical presentation of linear expansion as a function of temperature are presented.

Jan 1, 1961

By Frank J. Wiebelt, Spangler Ricker

"INTRODUCTION Bauxite, in Appalachian Alabama, occurs in the Rock Run and Goshen Valley districts in Cherokee County; in Nences Creek Valley near Jacksonville; near Anniston in Calhoun County; north of Fort Payne in DeKalb County; near Ashville in St. Clair County; and near Talladega in Talladega County.In February 1942, Preston E. Cloud, Jr., assistant geologist, Federal Geological Survey, began a study of these bauxite deposits and the geology relating thereto.The Bureau of Mines established field headquarters at Piedmont, Calhoun County, in July 1942. Mineral agreements covering a total of 11,097 acres were executed with 15 landowners in the Rock Run district; 38 in the Goshen Valley district, covering 7,575.5 acres; and 3 in the Nances Creek Valley district, covering 988.5 acres. Drilling was done on.the properties of 9 land¬owners in the Rock Run district, and on the property of 1 landowner each in the Goshen Valley and the Nances Creek districts. Drilling began October 26, 1942, and ceased on May 17, 1943.Power drilling was supplemented by a labor crew that drilled hand-auger holes in shallow deposits and sampled .old shafts, mines, and mine dumps.In all, 222 holes for a total of 13,250 feet were drilled. Of these toles, 88 penetrated bauxite but too low in grade to constitute ore."

Mar 1, 1948

By H. Tomlinson

"PURPOSE OF REPORTFatalities from falls of roof and coal are responsible for the death of more than 1,000 miners annually in the bituminous coal mines of the United States or practically one—half of the total fatalities in and about these mines. The men are killed by falls singly or in small groups and little or no publicity is given these accidents as they lack the spectacular features of gas and dust explosions. As a result, the public and even the miners have the impression that accidents from falls of roof and coal are just one of the unavoidable hazards of the coal—mining industry. This belief is not true. Accidents caused by falls can be avoided largely by the application of sound engineering principles, by education, and by proper leadership in the industry, just as gas and dust explosions and accidents caused by explosives have been reduced in recent years.The necessity for studying falls of roof and coal becomes apparent by referring to the following data from a table by Adams and Chenoweth:3"

Jan 1, 1933