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By R. F. Abernethy

The work discussed in this report was done by the Bureau of Mines to develop a method for determining trace amounts of fluorine in coal. Samples of coal mixed with calcium oxide as a fixative agent for fluorine were ashed at 600° C and the residue was fused with sodium carbonate. The melt was dissolved in phosphoric and sulfuric acids and distilled to separate the fluorine) which was determined in the distillate by a SPADNS-zirconium spectrophotometric method. Fluorine determinations of 83 commercial coals ranged from 0,001 to 0.019 percent.

Jan 1, 1967

By R. Unger, L. Mallett

The use of virtual reality (VR) technologies to train miners is an evolving area in research and development. In July 2006, representatives of 14 international organizations met to discuss current VR-related efforts and explore ways to employ VR in the future. This paper gives an overview of the various approaches presented at the meeting and discusses directions for future implementation. An example of a training package that teaches mine map-reading skills is presented. The meeting was the first step to building collaborations for furthering VR applications for mining. Planning has begun for a 2008 meeting open to broader participation. Disclaimer: The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the National Institute for Occupational Safety and Health.

By Neil B. Young

Analytical results for nahcolite, dawsonite, total extractable alumina, and oil yield are presented for samples representing Green River Formation oil shales in the saline section of two cores from Colorado's Piceance Creek basin. Analyses are also reported for samples extending the analyzed section of Colorado corehole No. 3 beyond that reported previously. These data permit evaluation of the deposit for possible production of three coproducts--shale oil, alumina, and sodium carbonates--from the saline section of the formation at these sampled points.

Jan 1, 1970

By T. J. Ballard

The Track Rock corundum mine was among the numerous corundum deposits investigated during the war by the Bureau of Mines in an effort to develop domestic reserves of that critical mineral. In the investigation of this property 562 feet of trenches were excavated and a l25-foot adit was reopened for the purpose of locating veins to of corundum which had been previously reported to occur in that locality. Only very minor amounts of corundum were disclosed in both the surface workings and the adit. The project was begun in May 1943 and completed in November 1943.

Jan 1, 1948

By L. E. Schultze

The Bureau of Mines operated a mineral recovery unit to recover metal values from post-flash geothermal brines from the Salton Sea known geothermal resource area as part of its research into the use of plentiful resources. The brine was available for metals recovery after its heat content had been used to generate electricity. The brine source was treated with lime to precipitate the contained iron, manganese, lead, and zinc before injection of the heat-depleted brine into the underground reservoir. Data are presented on the effects of process variables, such as rate and method of lime addition and air oxidation versus air exclusion. Variations in precipitation of metal values, composition of precipitates, effectiveness of slurry thickeners, and methods of treating the precipitates to recover metal values are discussed.

Jan 1, 1982

By Wm. C. Dean

The location of trapped miners from their seismic signals will be in- accurate if we assume the P-wave propagation velocity is a constant. P- wave velocities are anything but constant in regions about mines, so some calibration is necessary to obtain more accurate seismic locations. The reference event method compares the time arrivals of signals generated by the miners with those previously recorded from a reference or calibration event in the vicinity of the miners. This method locates the miners' position relative to the calibration source. Hence, the location of the miners is absolute if the reference event position is known absolutely, usually from surveys and mine maps. Advantages resulting from the system, besides greater accuracy, are locations independent of the velocity model assumed, the same solution from the full array and from any subset of four or more seismometers in the array (three if the miners' depth is known), fewer seismometers required, and no complex computers required for analysis. VELA Uniform experience shows that the accuracy of locations of teleseismic explosions and earthquakes is improved by an order of magnitude over locations computed from average travel time curves. Each calibration event is applicable only over a limited range. We recommend a field test of the method at a mine to measure its location accuracy, the range of effectiveness for each calibration event, the number of seismometers needed, and the number of reference events required per mine. From these experiments we could decide whether the reference event method was useful and, if so, what form a practical rescue system would take.

Jan 1, 1974

By Verne E. Hooker

Stress relief measurements were made at three underground test sites associated with the Henderson project, American Metal Climax, located in the rugged, mountainous region between Loveland Pass and Berthoud Pass on the Continental Divide in Colorado. Sufficient data were obtained to determine the three-dimensional stress ellipsoid for each site. The measurements were made at hole depths greater than one diameter of the mined opening; thus, calculated stresses are representative of premining in situ conditions. The vertical components of stress are in good agreement with overburden depth including the influence of mountain topography. Horizontal components of stress substantially increase with depth. These components are believed to be influenced by stresses presumably of tectonic origin. The largest measured principal stress was 5,900 psi at a depth of 3.708 feet. The predominant orientation of maximum principal stress for the determinations at greatest depth is in the NW-SE quadrants.

Jan 1, 1972

By Harold R. Newman

The performance of Ecuador's mineral industry continued to be affected not only by depressed oil prices in recent years but also by natural disasters. In March 1987, Ecuador canceled foreign debt payments for the rest of the year and appealed for international aid because of a series of earth-quakes that destroyed villages and crippled the nation's oil industry. The earthquake destroyed a key section of the country's main oil pipeline and forced a halt to production and shipment of Ecuador's most important export product. Ecuador produces 240,000 barrels of oil per day and exports 144,000 barrels daily. Oil accounts for 60% of the nation's hard currency earnings. The Government of Ecuador asked the Organization of Petroleum Exporting Countries and other oil-producing countries to assume Ecuador's oil sales commitments. Ecuador agreed to pay the countries back in an equivalent amount of oil when it was able to resume exports.

Jan 1, 1989

By Sarah P. Guerrino

This chapter summarizes data on crude nonfuel mineral production for the United States, its island possessions, and the Commonwealth of Puerto Rico. Included also are the tables that show the principal nonfuel mineral commodities exported from and imported into the United States and that compare world and U.S. mineral production. The detailed data from which these tables were derived are contained in the individual commodity chapters of Volume I and in the State chapters of Volume II of this edition of the Minerals Yearbook. Although crude mineral production may be measured at any of several stages of extraction and processing, the stage of measurement used in this chapter is what is normally termed ?mine output.? It usually refers to minerals or ores in the form in which they are first extracted from the ground, but customarily includes the output from auxiliary processing at or near the mines.

Jan 1, 1987

By M. G. Downey

The stone resources in certain localities and the kinds of stone available often influence manufacturing companies in their choice of plant location and in possible expansion of their activities. Limestone in particular is an important raw material for many processing industries. In planning highways and public works and placing contracts therefor, the availability of aggregates and road stone is significant. On the other hand, persons who contemplate entering the stone business or opening now quarries need information as to possible competition. To meet the growing need for regional data of this type, the Bureau of Mines has compiled from its records and presents herein the location of stone quarries by States and counties and by kinds of stone. The list covers all stationary and portable commercial quarry operations whose production statistics for 1940 were reported to the Bureau of Mines but does not include undeveloped deposits and noncommercial or Government-operated quarries.

Jan 1, 1941

By Linda L. Chasko, Charles P. Lazzara, Ronald S. (deceased) Conti, William J. Wiehagen

Fire has long been a concern for underground mine workers. A mine fire can occur at any time and can result in a partial or total evacuation of mine personnel and the loss of lives. Fires can grow rapidly. Time is the critical element. Prompt detection, timely and accurate warnings to those potentially affected, and a proficient response by underground miners can have a tremendous impact on the social and economic consequence of a small underground fire. Fire preparedness and response have components of technology and people. These components can work synergistically to reduce the time it takes to bring the system back in balance. This report deals with the preparedness of miners to respond to underground mine fires. It is intended to aid the mining industry in understanding the various roles of emergency responders and the training techniques used to increase their skill levels. The report also presents a technology overview to assist in effective response to mine fires.

Jan 12, 2005

By R. D. Leitch, W. P. Yant

"In the course of another investigation4 during 1926 and 1927, samples of water collected from a few abandoned coal mines indicated that their drainage was usually lower in acidity than water from active mines in the same locality. In order to determine whether this condition might have a bearing on the advisability of sealing abandoned mines, a number of such mines were visited, samples of drainage were collected, and as much information- as possible was obtained from officials of the mining companies and older residents of the district. The results of this work are the basis of the present report.The authors are indebted to E. W. Robertson, F. F. Spowart, J. H. Nagle, and W. D. Adams of the Northwest Mining & Exchange Co.; E. M. Fasset, Fred Lane, Wm. Humphreys, and Dr. T. A. Hutchison of Brockway, Pa.; C. W. .Faulk of the Shawmut Mining Co.; James Hau of Kersey, Pa., and to others for information received; and to Dr. R. R. Sayers of the Bureau of Mines, under whose direction the work was conducted.The Lower Kittanning is the most important bed in the locality studied. A great many of the abandoned mines examined are in this bed, and nearly all of the present active ones are. The Upper Freeport bed is also mined to some extent, and a number of the abandoned mines formerly worked this bed. As only three active mines are now (1927) working the Upper Freeport, the comparison of acidities is necessarily limited. Of these three, one had been idle since 1922 until shortly before it was sampled.The location of most of the mines was already known from previous work, but some of them had to be located by following up streams known to contain acid waters. A sample of the- outflow was collected in self-sealing bottles known as ""citrate bottles"" for the determination of dissolved oxygen by the Winkler method.5 Another sample was taken for the determination of acidity according to standard methods of water analysis.6 Ferrous iron was determined at the mine or very soon after taking the sample by titrating with a standard solution of potassium permanganate in acid solution. The hydrogen-ion value was determined by a standard double-wedge comparator.7From the total acidity values in each sample, which are the most important values, the total iron was calculated on the assumption that acidity as sulphuric acid was due to dissolved ferrous sulphate. This assumption is commonly made for mine waters, but is inaccurate to the extent that free acid is already present, and some of the iron is present as ferric, rather than ferrous, sulphate. The amount of ferrous sulphate may be a rough measure of the extent to which oxygen is lacking within the mine. The permanganate titrations just mentioned showed what part of this total iron was in combination as ferrous sulphate, and the difference .was assumed to be that in combination as ferric sulphate, after correcting for the amount of free acid already formed as shown by the titration values."

Oct 1, 1928

By H. H. Schrenk

One phase of the Bureau of Minest work in the field of health and safety is the promotion of safe, satisfactory, and reliable respir atory protective devices. To insure that such devices will be available, the Bureau has established schedules of what it considers the minimum re- quirements for oxygen breathing-apparatus,3 gas masks, hose masks,5/ and mechanical filter-respirators (a schedule of requirements for hose- type supplied-air respirators is being prepared). Approval of oxygen breathing-apparatus is given by the Safety Division; approval of other types of respiratory equipment is given by the Health Division, both divisions being in the Health and Safety Branch, Manufacturers of respiratory protective devices may submit their equipment to the Bureau for approval under the requirements of these schedules. As a prerequisite to submitting a device for approval, the Bureau requires a statement that the device is completely developed and of the design and material that the manufacturer believes suitable for a finished marketable device; that the device has been

Aug 1, 1937

By Jeffrey M. Listak

The Respiratory Hazards Control Branch of NIOSH routinely conducts laboratory and mine-site evaluations of dust control technologies. Gravimetric and instantaneous dust sampling instruments are used in these evaluations to measure and document dust levels to determine worker exposure. The Thermo personal DataRam (pDR) is an instantaneous sampler that uses light-scattering technology to provide relative measures of airborne respirable dust. The pDR can be used in active and passive modes to measure respirable dust levels. Tests were conducted to evaluate the sampling performance of active and passive pDR operation relative to each other and. against a gravimetric sampler (the accepted standard for respirable dust measurement). The purpose of the test was to determine if the pDR can be used effectively in the passive mode in higher velocity airflows (up to 5.1 m/s (1000 fpm)). Studies of the pDRs in both modes of operation were conducted in a controlled laboratory environment and in field situations. Dust measurements using pDR units in both modes of operation were recorded in ve¬locities ranging from 1.0 to 5.1 m/s (200 to 1000 fpm). Tests were conducted in ambi¬ent air and in air with the addition of moisture. Results show that, although the units measure different concentrations in their respective modes of operation as compared to a gravimetric sample, the relative readings can be corrected to yield accurate dust measurements.

Jan 1, 2007

By Franxis Church Lincoln

"INTRODUCTION During September 1944, the Bureau of Mines undertook a program of investigation and limited exploratory drilling at the Last Chance mine, near the village of Arthur in Grant County, Wisconsin, as part of a general investigation of the zinc-producing area of southwestern Wisconsin when every effort was being made to increase the production of metals important to the Nation's war program.The Bureau's attention was directed, to the Last Chance mine when the operators discovered high percentages of zinc in an exploratory churn drill hole a short distance southeast of the mine. The ore was found in the Trenton Limestone, which underlies the ore horizon then being mined. To determine whether this discovery was important, and to demonstrate the possible extension of the ore the Bureau of Mines drilled five additional holes in the vicinity of the discovery.ACKNOWLEDGMENTSIn its program of exploration of mineral deposits, the Bureau of Nines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report."

Mar 1, 1947

By Jeffrey M. Listak

The Bureau of Mines has conducted a rock mechanics study to monitor deformation of near-seam strata above a longwall panel in the Pittsburgh Coalbed. The primary goal was to determine the height of caving immediately behind advancing longwall face supports. This study, although site specific, provides information on the caving mechanism associated with longwall extractions so that strata behavior and its interaction with longwall face supports can be better understood. Two holes were drilled, approximately 550 ft apart along the center line of a longwall panel, from the surface to the coalbed approximately 650 ft below. Various downhole geotechnical instruments were used to monitor strata deformation. In addition, surface elevation surveys were conducted to differentiate between surface and subsurface activity. This report discusses the caving characteristics of the strata as the longwall panel approached and passed beneath the boreholes. Physical property data are also presented to demonstrate the relationship between caving behavior and local geology. Data show that immediate caving of strata above the longwall face occurred at a height less than 23.5 ft and that strata behavior above longwall extractions is highly dependent upon lithology, with major disturbances occurring at weak lithologic zones.

Jan 1, 1986

By I. AITKENS

It is a common misconception that all yellow stones are topazes and that all topazes are yellow; but neither statement is true. The real topaz is a rather rare mineral, and a large number of yellow stones that masquerade as topaz are nothing more than yellow quartz, known as citrine, but almost universally called topaz. The true topaz is often called "Brazilian" topaz by the jeweler to distinguish it from yellow quartz; nevertheless, both terms are freely applied in trade to other yellow stones. Topaz is considered the most popular yellow stone for jewelry and is often used as the principal stone in brooches or pendants, especially in old-fashioned ornaments. However, many other species yield pretty yellow stones, some of which are far more numerous and less costly than the topaz.

Sep 1, 1931

By George S. Rice

A novel method of extinguishing a mine fire in a stowed or gob-filled area by employing liquid carbon dioxide under high pressure eras used recently with success at the President (Prasident) coal mine, Bochum, Germany, as reported by P. Cabolet in Gluckauf (Apr. 24, 1937, p. 393) The use of carbon dioxide gas as a fire-fighting agent in surface plants and in ships is now general practice in the United. States, but when it has been tried for extinguishing fires in mines in large areas more or less confined by stoppings it has not been successful. Examples of the latter method of attempting to fight mine fires are given in Bureau of Mines Bulletin 229, Fifty-Nine Coal-Mine Fires; How They Were Fought and That They Teach, by G. S. Rice, J. VT. Paul, and 14. VT. von Bernewitz (1927). The reason for its nonsuccess may be either that the stoppings are not tight or that the roof and pillars are more or less fissured and enough air passes into the area to sustain a slow fire, whether of spontaneous origin or produced by gas explosion or other source of ignition.

Jan 1, 1937

By H. Kenneth Sacks

The Bureau of Mines has developed hardware for electromagnetic (EM) detection and location of miners trapped in underground coal mines. This report describes a technique for using the developed equipment for locating uncased boreholes underground. Results of several field and laboratory experiments are described.

Jan 1, 1978

By Collin Stewart, Greg Hunt, Christopher Mark

Bowie Resources maintains one of the most pro-active ground control programs in the U.S. mining industry today. Its guiding philosophy is that everyone in the organization, from the miners at the face all the way through the top management, are involved in ground control. Some of the unique elements of the Bowie ground control program include: • Roof bolt operators log the stratigraphy of test holes in nearly every cut. These “lith-graphs” are used by section foremen to determine the need for additional roof support, and they are entered into the geologic data base for use in geologic modeling and mapping. • Underground core drilling is conducted to obtain data for CMRR and stability maps. • Weekly “Quality” meetings, involving mine management and technical staff, are held to ensure that ground control information is integrated into production operations. The paper will describe the program in detail, discussing the involvement of roof bolters, section foremen, surveyors, technical staff, and production managers. It will also show how the program has contributed to the mine planning process. Case histories of successful ground control interventions will be discussed.