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By C. L. Wright

In 1904 the Government began a series of fuel-testing investiga- tions at its fuel-testing plant at St. Louis, Mo. These investigations, which were placed under the supervision of the United States Geo- logical Survey, included chemical analyses, steaming tests, gas- producer tests, briquetting tests, coking tests, and washing tests of samples collected from the various coal fields of the country. The specific purpose of the investigations was to analyze and test the coals and lignites in the United States, in order to deternime their fuel values and the most efficient methods of utilizing them for different purposes. Part of the fuel-testing plant, including the briquetting equipment, was moved to Norfolk, Va., in 1907, and the fuel-testing investiga- tions were made one of the divisions of the technologic branch of the Geological Survey. In 1908, after the close of the Jamestown Exposition, most of the fuel-testing equipment was removed to its present location at the Pittsburgh experiment station, Fortieth and Butler Streets, Pittsburgh, Pa. In 1910, an act of Congress, effective July 1, established the Bureau of Mines in the Department of the Interior and authorized the transfer to this bureau of the fuel-testing investigations that had been carried on by the technologic branch. Bulletins presenting the results of various inquiries and investiga- tions relating to briquetting have been published by the Geological Survey and the Bureau of Mines. As the supply of some of these bulletins is exhausted, the Bureau of Mines has decided, instead of reprinting them, to publish the more important facts they contain

Jan 1, 1913

By W. H. Ode, W. A. Selvig

Investigations have shown interesting relationships between primary-tar and light-oil yields and chemical analyses of coals. These studies have been based largely upon results published by the Bureau of Mines in connection with its survey of the gas-, coke-, and byproduct-making properties of American coals. This paper gives the results of a similar correlation in which the range in rank and type has been extended to include nearly all classes of coal, the object being to determine relationships that are significant in predicting tar and light-oil yields from chemical analyses of coals. The yields of primary tar and light oil are important in two fields of coal utilization, namely, combustion and carbonization. It is generally recognized that the principal cause of smoke produced upon burning coal is incomplete combustion of tar and light-oil vapor released during burning. The greater the tar and light-oil yields of a coal, the greater is its potential smoke-producing property. During the present war, development of new sources of fuel oil has been emphasized, especially where the supply of petroleum products is limited. One possible source of a substitute fuel is the tar and light oil that can be obtained by low-temperature carbonization of coal. In both England and Germany large quantities of low-temperature tar and oil are being processed as a source of liquid fuels. It is obvious that primary-tar and light-oil yields are of paramount importance in the selection of coals for such use.

Mar 1, 1944

The optimum situation in sealing the soil with latex would be to locate the sealant at the depth where natural permeability is lowest, and to narrow distribution of the latex to a film. To ascertain how closely we were achieving these objectives it was necessary to devise a method to measure the concentration of latex in soil. A number of methods were explored and two were used in actual field tests. SBR latex tagged with c14 was prepared and used to determine the distribution of polymer in the soil. The latex was made by copolymerizing a mixture of radioactive and normal styrene with butadiene in bottles by conventional methods. Average particle size was 600 Å. Diluted aliquots had 1.40 microcuries radioactivity per gram of latex. Tagged latex was mixed with soil in a range of proportions from 0.01 to 0.25% by weight to develop a calibration curve. Analyses of soil in the laboratory and from the field were determined by comparison with this master curve. Styrene-containing polymers have a characteristic peak at 700 cm-1 but crosslinked SBR is not soluble in solvents normally used in infra-red spectroscopy, e.g., carbon disulfide. We developed a method for solubilizing the crosslinked polymer by stirring overnight at room temperature a soil sample in chloroform with t-butyl hydroperoxide and osmium tetroxide. The filtered chloroform residue was dried to constant weight, thoroughly mixed and pressed into a KBr pellet, and concentration was determined by measuring the absorption at 700 cm-1. Details are given in an Appendix.

Jan 1, 1972

By R. V. Ramani, R. Stefanko, G. W. Luxbacher

The Federal Coal Mine Health and Safety Act of 1969 has dictated major changes in mine ventilation with regard to both air quantity and quality. Requirements have also been placed on the ventilation of beltlines, gob and face areas, and air velocities on trolley haulage roads are limited. Escapeways, separate from trolley haulage roads and on an intake split of air, must be maintained continuous to the surface. These and other similar requirements have not only precipitated several modifications to existing ventilation systems but also have greatly increased the complexities of new mine ventilation planning. It is apparent that the use of computers in ventilation system analysis and design is a necessity. SUMMARY Although computer oriented analysis of mine ventilation systems was introduced over two decades ago, it has yet to receive widespread acceptance in the United States. Central to this problem is the fact that, while many computer programs for network analysis have been developed, no attention has been paid to the development of computer input data. Consequently, without this foundation, program applications have been infrequent. This thesis has directly attacked this problem and has presented all pertinent information basic to the development of good computer input data. The areas that were covered include quantity measurement, pressure measurement, fan testing, survey data balancing, and the development of a network schematic from the ventilation survey results. These discussions on data collection and the corresponding reduction to computer coding have been illustrated by an application of a ventilation simulation program to an existing mine in Southwestern Pennsylvania. The use of a ventilation

Jan 1, 1977

By H. H. Schrenk, Carlton E. Brown

"INTRODUCTION The question as to whether or not the flow of water through pneumatic rock drills commonly used in this country keeps to a minimum dust disseminated into the air during drilling arose during a study of the dust-in-air conditions in Butte mines from February to July 1936 and December 1936 to June 1937 made by the Bureau of Mines in cooperation with the Anaconda Copper Mining Co., Butte, Mont, The purpose of this report is to describe the study, including some experimental work on the subject, and to give test results.ACKNOWLEDGMENTSThe help of the ventilation department of the Anaconda Copper Mining Co. in planning the study and collecting the data is gratefully acknowledged.EXPERIMENTAL CONDITIONSTests were conducted in an untimbered 6- by 8-foot crosscut in medium-hard granitic rock near the shaft station on an inactive level of one of the active Butte mines. Figure 1 shows the plan and section of the test location. Air was drawn from the shaft at the station, through the crosscut, and up through another shaft. The flow of air through the crosscut was decreased by a brattice downstream from the sampling location, so that relatively high, easily measurable dust concentrations would be obtained in the tests. Impinger samples for determing concentration of dust in the air were collected in an opening 51 inches wide, 29 inches high, and about 4o inches from the top of the rails in a wooden stopping about 16 feet downstream from the place where the test holes were drilled."

Apr 1, 1938

Reduce rockfall fatalities and injuries by using innovative blasting practices to reduce damage to the rock at the excavation limits with little or no increase in cost. The Problem Falls of highwall have been a leading cause of fatalities, injuries, and equipment damage in the surface mining industry. Although the number of highwall falls is not great, when such an incident does occur it is about 14 times more likely to be fatal or result in severe injury and damage to equipment than other types of surface mine accidents. Overbreak or damage to the rock from poor or improper blasting practices is a major factor contributing to rock falls. Presplitting or cushion blasting is the technique most often recommended for improved wall control. This type of blasting however, adds to drilling and blasting costs and is not universally accepted by the industry. Air gap presplitting techniques, also called air decks, are currently being used in some mines as a less costly alternative to conventional presplitting. Approach Blasting can cause highwall damage, but proper blasting techniques have been shown to reduce the magnitude of rockfall problems. In preventing rock falls, it is important to maintain the natural strength of the rock structure to the greatest extent possible. Improved blasting practices have three main advantages: 1) they are preventive rather than corrective in nature; 2) they are cost effective; and 3) they have a very low impact on the mining operation when properly implemented. New ways of evaluating highwall integrity, such as seismic refraction tomography, were investigated.

Jan 1, 1991

By T. L. Joseph

"In the January 3 issue of Iron Trade Review, Sweetser2, in referring to the problem of coke combustibility, points out that, ""Someone should formulate a rule for the rate of flow of coke through the zone of coke combustion that now appears to be confined to a comparatively restricted volume in front of the tuyeres,"" In formulating such a rule it is necessary to distinguish clearly between combustibility, a property of the fuel, and rate of combustion, which is determined by the rate at which air is supplied to the fuel bed. The rate of carbon gasified at the tuyeres of a blast furnace is independent of coke combusti-bility. A fast-burning coke will burn in a more restricted volume than a slow-burning coke, but both types of fuel will be consumed at rates determined by the supply of oxygen,A number of the definitions of combustibility that have appeared in technical literature relate more closely to rate of combustion than to combustibility. Perrott and Kinney) have correctly defined it as follows: ""Combustibility of coke from the standpoint of its use in, the blast furnace is inversely proportional to the mean rate of gasification per unit volume of the combustion zone, assuming other factors remain constant,"" Combustibility of coke refers therefore to those properties that determine the size or extent of the combustion zone. Relative differences in these properties can be measured by the depth of the fuel bed required to convert oxygen from the air into carbon monoxide."

May 1, 1924

By Jon K. Ahlness

The Bureau of Mines, in cooperation with the Institute of Mineral Research of Michigan Technological University, and the Upper Great Lakes Regional Commission, conducted an investigation of electronic sorting of native copper ore from Upper Michigan. This report is based on research by the Institute of Mineral Research under contract to the Bureau. The test program evaluated the use of belt and rotary sorters on various size and grade fractions of ore. Both plant-scale sorting and lab sorting tests were run. The plant sorting objectives were to determine the sortability of different ores and the efficiency of the electronic ore sorters. High-and low-grade ores from both conglomerate and amygdaloid types were separated into four size fractions. The two larger sizes were sorted on belt sorters and the two smaller ones on rotary sorters. Copper recoveries ranged from 20.0 pct from a feed grade of 0.40 pct to 80.3 pct from a feed grade of 1.08 pct. Lab sorting tests of conglomerate ore were run to determine the efficiency of a belt sorter equipped with a second sensing coil located above the belt and to determine the sorting characteristics of larger ore size fractions than those used in the plant sorting. Copper recoveries from the combined feed sizes ranged from 47.0 pct from a feed grade of 0.13 pct to 96.8 pct from a feed grade of 4.87 pct. For all the ore types except one, it was found that the copper recovery increased with the feed size.

Jan 1, 1980

By John J. Mulligan

Lead-silver deposits in the Omilak area, on the western slopes of the Darby Mountains, Seward Peninsula, Alaska, were investigated by the Bureau of Mines, during the 1953 and 1954 field seasons, as a part of the U.S. Department of Interior's continuing program for the development of Alaska's resources. The Omilak area was the scene of early day prospecting and mining activity. The Omilak mine, which operated from 1881 to 1890, was the second producing lode mine in Alaska; the first was a small gold mine near Sitka. Several hundred tons of ore were produced at the Omilak mina; as an indication of grade, 41 tons shipped from Omilak in 1889 contained 75 percent lead and 142 ounces of silver per ton. A prominent, nearby occurrence of lead-silver minerals, found but not explored during this period, has since become known as the Foster prospect. Subsequent exploration of this prospect revealed an abundance of massive galena occurring on an outcrop and as float scattered through limestone talus. Evidence of lead deposition, together with the generally high silver content of lead ores previously shipped from the district, indicated that deposits might be found which would be commercially valuable even in this remote area. To investigate the possibility, the Bureau of Mines made a reconnaissance of the Omilak area and did bulldozer trenching, diamond core drilling, and sampling at the roster prospect. Data resulting from the investigation are presented in detail in this report and are summarized in the following paragraphs.

Jan 1, 1962

1. In 2001, a total of 7,131 sand and gravel mining operations reported employment statistics to the Mine Safety and Health Administration (MSHA). Sand and gravel mines comprised 48.8% of all mining operations, the largest percentage of all mining sectors. Sand and gravel mines are distributed throughout all 50 states. The median number of operator employees per sand and gravel mine was 3.0.

Jul 1, 2003

In 2007, a total of 725 nonmetal mining operations reported employment to the Mine Safety and Health Administration (MSHA).1 Nonmetal mines com-prised 4.9% of all m ining operations. ? Mines producing common clay comprised 25.4% (n=184) of all nonmetal mining operations. ? Nonmetal mining operations were located in all states and territories except Alaska, Delaware, Hawaii, Maine, New Hampshire, Rhode Island, Puerto Rico, and the U.S. Virgin Islands.

Aug 1, 2009

In 2007, a total of 7,199 sand and gravel mining operations reported employment to the Mine Safety and Health Administration (MSHA).1 ? Sand and gravel mines were the largest mining sector, comprising 48.4% of all mining operations. ? Sand and gravel mines were found throughout all 50 states and Puerto Rico.

Aug 1, 2009

Lower the respirable dust exposure of longwall shearer operators by use of a modified head to tail cutting sequence. Approach Modify the cutting sequence of double-drum shearer operations cutting unidirectionally head to tail, so that the tailgate drum is used to mine the entire coal face except when cutting out at the head. This approach would place the primary dust generating source, the cutting action of the drum, on the return air side of both shearer operators. How It Works Currently, 75% of the double-drum shearers in operation employ a unidirectional cutting sequence. On half of these operations, the primary cut is taken as the shearer travels from the headgate to tailgate ends of the face, with roof support to be advanced on the intake air side of the shearer. Typically, the leading (tailgate) drum is taking a full cut during the head to tail pass and the trailing (headgate) drum is cutting bottom coal. In this mode of operation, the dust generated by the trailing (headgate) drum can spread out into the walkway, and increase the respirable dust exposure of both head and taildrum operators. As an alternative, if the trailing drum is "free wheeling" or cutting minimal coal during the head to tail cut, and bottom coal taken by the tailgate drum during the tail to head clean-up pass, both operators are able to work on the intake air side of the primary dust generating source (drum) except when cutting out at the head. This modified cutting sequence would save wear on the conveyor and help to eliminate overloads, as well as reduce the respirable dust exposure of both shearer operators. This modifcation is only applicable to long-wail operations currently cutting unidirectional head to tail, and to those operations where this unidirectional cut would not produce operating constraints.

Jan 1, 1981

By W. H. Kerns

The Simon & Coles manganese deposit in Sherman Valley, Bedford County, Pa., was investigated by the Bureau of Mines during the fall of 1942. Two churn-drill holes; 65 and 75 feet deep were bored, and 8 channel samples were taken. Manganese occurs at this property in the form of psilomelane and manganiferous iron as replacement of the red sandy shale of the Much Chunk-formation. Two cars of manganese ore had been shipped by the owners in 1940, of which one averaged 10.9 percent manganese and the other 21.3 percent manganese. One car of hand-sorted manganese ore that averaged-45 percent manganese was shipped in 1942.

Jan 1, 1948

By C. A. Alien

The increasing activity in oil shale has had a tendency to direct the attention of the industry to any substance from which gasoline or other oils can be secured . Cannel coal for many years has been known, as a source of oil and formerly it was the only substance from which kerosene was obtained . The name of coal oil was given to kerosene because it was derived from cannel coal before any flowing wells were brought in in the United States . In an isolated region in Southern Utah there is an unusually thick and clean bed of cannel coal which laboratory experiments indicate can be made to yield about seventy gallons of oil to the ton . This coal was first described in Bulletin 341 of the United States Geological Survey under the title of Colob coal field . This field lies at the western and southern base of the Colcb plateau and extends from the town of Cedar City southward to Kanarra and then southeastward to the town of Mount Carmel . Cedar City is 35 miles south of east from Lund on the Los Angeles and Salt Lake Railroad which is the nearest railroad point . Mount Carmel is about 90 miles south of Marysvale , on the Denver and Rio Grande Railroad , which is the nearest railroad point from the eastern end of the field . The Colob coal occurs in Lower Cretaceous rocks and a number of wagon mines have been opened on the seam in the vicinity of Cedar City , Kanarra , and Mt. Carmel , but between these places the field has been very little prospected . The cannel coal , so far as known at present , is limited to a small area on the head waters of the north fork of the Virgin River in Township 39 and 40 South , Range 9 East . In this region it occurs as a bed 5-1 /2 feet thick over which lies a layer of bituminous coal 2 feet and 5 inches thick .

Feb 1, 1921

By J. B. Zadra, S. M. Shelton, M. M. Fine

"Ferrograde manganese ore or its equivalent is essential to the manufacture of every ton of steel produced; although it is well known that there are large deposits of low-grade ore in the United States, the production of substantial amounts of ferrograde material from domestic sources presents a problem that becomes more and more critical as the stockpiled ore is depleted through inability to procure adequate supplies from foreign sources. Consequently, a program of laboratory and pilot-plant investigation designed to solve the problem of obtaining a domestic supply of manganese has been undertaken by the Metallurgical Division, Bureau of Mines.This paper is one of a new series that will include reports of results obtained in the various investigations conducted under the manganese program. The scope of the program and the organization that woo set up to direct and supervise the work were discussed in the foreword of the first paper of this series, Report of Investigations 3606, Manganese Investigations. 1. Concentration of Manganese Ores from the Drum Mountain District, Utah, by S. R. Zimmerley, J. D. Vincent, and C. R. Schack. Other reports will be published as the work progresses."

Mar 1, 1942

By M. Clair Smith

The Bureau of Mines investigated the Rip Van Winkle mine, which is about 25 miles northwest of Elko, Nev., from October 1942 to February 1943 to determine possible resources of lead-zinc-silver ore. The property is owned by the Rip Van Winkle Consolidated Mining Co., which maintains its offices in Salt Lake City, Utah. Ore was discovered in the 1860's, and active mining was carried out intermittently until 1939, when the Rip Van Winkle Consolidate Mining Co. acquired the property. This company equipped and developed the mine, erected a flotation mill, and operated on a 65-ton daily basis. The ore is mined from veins, mineralized faults, and replacement deposits of wall rock. The country rock comprises cherty shale, granite, porphyry, intrusive breccia, and breccia, and brecciated shale. Mining operations were carried down to the 700-foot level. The Bureau of Mines drilled 5 diamond-drill holes, totaling 1,084 feet, from the 600- and 700-foot levels, excavated a 250-foot surface trench, and took 26 underground samples. The ensuing sections note the location and physical features of the district, mention the equipment, and specify the property and ownership. The history of the mine is briefed, and the geology, mine workings, and plant are described. The work performed by the Bureau of Mines is summarized and supplemented in detail by assay maps, logs of diamond-drill holes in appendix A, and by tables of sample analysis in appendix B.

Jan 1, 1949

By R. V. Ramani, C. B. Manula, A. Owili-Eger

All the input data required to operate the ventilation simulator except the title, are entered with I10 or F1O.O formats. The title is entered with (18A4) format. The floating points are designated by (FP) and the integers by (INT)

Jan 1, 1975

By G. A. Burrell, G. W. Jones

As a part of the work which the Bureau of Mines carried out in 1916 and 1917 pertaining to the compressibility of natural gas , it became necessary to de termine the pressure -volume relations of several of the paraffin hydrocarbons of which natural gas is composed . Results of the work on natural gas were published in Technical papers 131 (Burrell , G.A. , and Robertson , I.W. , The compressibility of natural gas to high pressure , Bureau of Mines Tech . Paper 131 , 1916 , 12 pp. ) and 158 (Burrell , G.A. , and Robertson , I.W. , Compressibility of natural gas and its constituents with analyses of natural gas from 31 cities in the United States , Bureau of Mines Tech . Paper 158 , 1917 , 12 pp . ) , and curves were given of pressure volume deviations of the gases , methane , ethane , propane , and carbon dioxide at high pressures . original experimental data on these gases , however , were not published . The In view of many inquiries which the Bureau has received with reference to the original data on the se gases , and the importance of the pressure -volume relations from which it is possible to calculate the deviation of any natural gas who se composition is known , the original data as determined by Burrell and Robertson are pre sented below .

Aug 1, 1921

By L. M. Demers, D. C. Kuhn

The alveolar macrophage (AM) responds to stimuli such as coal mine dust by releasing inflammatory mediators such as cytokines, growth factors. reactive oxygen species. and eicosanoids. Eicosanoids are synthesized by°AM through the action of cyclooxygenase and lipoxygenase enzymes and serve to modulate the proinflammatory function of this cell as part of the lungs' host defense mechanism. Reactive oxygen species can be generated by AM as a by-product in the biosynthetic pathway of the prostaglandins. AM produces primarily prostaglandin E2, thromboxane A2, and leukotriene B4 as part of the cellular response to an inflammatory stimulus. There is evidence to suggest that eicosanoid production by AM is functionally linked to both surface interaction with mine dust particles like silica and by the phagocytosis of the dust particle itself. In this report, we examined the effects of an antioxidant, vitamin E. on dust-induced synthesis of PGE2 and TXB2 in vitro and in vivo by AM obtained by bronchoalveolar lavage from rats. We also looked at the effects of the surface of silica particles on AM eicosanoid biosynthesis under conditions of calcination, a process that removes exposed hydroxyl groups from the surface of silica particles, thus reducing the likelihood of soluble hydroxyl radical formation. Treatment of AM with vitamin E in vivo and in vitro reduced the augmentation in eicosanoid production usually observed when AM are exposed to mine dusts. These results suggest that vitamin E may effectively reduce the inflammatory and fibrotic response produced by inhalation of mineral dust through an antioxidant mechanism. Silica that has been chemically altered by calcination was unable to activate AM eicosanoid production in vitro when compared to untreated, freshly fractured silica. These findings suggest that the mechanism by which dust particles can activate AM eicosanoid release may involve interaction of surface and/or soluble factors with the cell membrane. Taken together, these studies point to the involvement of AM eicosanoid production as part of the proinflammatory response of this cell to occupational inhalation of mineral dust. - Environ Health Perspect 102(Suppl 10):97-100 (1994)

Dec 1, 1995