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By Robert F. Chaiken

A novel approach to eliminating environmental and public safety hazards that are associated with fires in abandoned coal mines and waste banks involves the use of in situ combustion technology developed by the Federal Bureau of Mines to accelerate the burning of the wasted coals in place. This technology would be used under exhaust ventilation control conditions that would allow for total management of the hot gases produced. Combustion stoichiometries would be optimized to minimize unburnt combustibles and to maximize the heat content of the gas products, which will be exhausted at one or more fan locations. When necessary, scrubber systems would be employed to remove air pollutants, such as sulfur dioxide; heat utilization systems (process heat, steam, and electricity) would also be employed to offset operational costs. Ultimately, complete burnout would solve the fire and acid water formation problems of the abandoned coal mine or waste bank. Pertinent technical data for burnout control are derived and discussed in terms of the important material and operational parameters. In general, it is believed feasible to operate a burnout system in an existing abandoned mine or waste bank fire at thermal power levels in the range of 10 to 100 Mw, and at exhaust gas temperatures of 1,000° C (1,830° F).

Jan 1, 1980

By Robert L. Chufo

The paper, "An Electromagnetic Roof and Rib Thickness Sensor" presented at The 12th WVU International Mining Electrotechnology Conference in 1992, presented the results of roof coal thickness measurements in underground mines and rib coal thickness measurements in highwall mines. The microwave sensor described uses a unique spatial modulation scheme created by antenna motion, along with frequency domain signal processing, to solve the problem of media, target, and antenna dispersion. This paper further describes the advantages of the unique frequency domain signal processing technology chosen by the U.S. Bureau of Mines in extending previously reported one-dimensional thickness measurement technology to the generation of a full three-dimensional underground image of the underground environment. The electromagnetic signature of a media, whether it is coal or other geological material, is its permeability and permittivity and the effect on the velocity and amplitude of an electromagnetic wave as it passes through. High-quality imaging cannot occur without the identification of, and correction for, the permittivity and permeability of each layer of a multilayer geological deposit. Clutter, or any signal that can interfere with target discrimination, usually comes from objects in the field of view for which there is no design control. These are nuisance targets with possibly very high contrasts compared to the real target. The only proven tool to reduce clutter is to increase spatial, spectral, and polarization diversity. This paper will describe some techniques being used by the U.S. Bureau of Mines to increase the information content of both single-dimensional and three-dimensional imaging systems through the identification of media distortion mechanisms made possible by the use of spatial/spectral sensor technology. These techniques will permit high quality imaging in an environment where the data is corrupted by dispersion and clutter.

By Robert F. Chaiken, Alex C. Smith

INTRODUCTION The National Institute for Occupational Safety and Health (NIOSH) at its Pittsburgh Research Laboratory (PRC) is interested in the application of water mist sprays to extinguish diesel fie1 fires in underground mine diesel refueling areas. To this end experimental studies have been carried out on the extinguishment of diesel fuel fires at PRL's large enclosed fire suppression facility (FSP) at its Lake Lynn Laboratory (LLL). Two sizes of shallow fuel pans (3x3 ft and 5x7 ft) contained the fires, and a number of commercial mist spray nozzles (at roof locations) and spray/fire locations were tested (52 fires in all). Visual observations of the pool fire extinguishment process by the overhead sprays with an infra-red sensitive videocom suggests that there are two distinct actions involved in extinguishment due to two different transport mechanisms by which the water droplets can enter the fire plume. First, is a direct injection of water droplets into the plume from overhead. This is believed to involve larger water drops and leads to an extinguishment time of several minutes. Second, is an indirect injection process involving small water drops which are entrained in the sideways air flow that feeds oxygen to the fire. This second process apparently leads to relatively fast quenching of the fire in less than 1 minute - a highly useful attribute for a fire protection system. This paper describes a relatively simple parametric model for the indirect water injection process, and defines the critical spray conditions for achieving rapid quenching of the pool fire. While the model is consistent with the pool fire data obtained to date, the PRL studies are continuing with more complex pool fire scenarios. It remains to be seen if this simple parametric approach applies to these future fire tests. THEORETICAL Critical Drop Size In the two-dimensional representation of figure I, an oil pool fire is considered to be a cone whose base is the vaporizing liquid oil surface having an area n?, above which exists a fire plume diffusion flame) of height, L. The rising plume induces a horizontal air flow into the side of the plume supplying the oxygen necessary for propagating gas phase combustion reactions. Water droplets suspended in the air around the plume will tend to follow the horizontal air flows into the plume. The rate of air entrainment by the plume will be determined by the overall combustion reaction which is assumed to be

By D. Harrington, B. W. Dyer

"Two recent occurrences in Western metal mines in each of which 3 men were killed due to breathing fumes from explosives, have aroused keen interest among mining men not only as to the exact cause of such accidents, but also as to possible preventive measures.In sinking the forty five degree incline Marsh *haft near Burke, Idaho, on May 13, 1920, a round of holes containing about sixty pounds of 40 per cent gelatin explosive was blasted by the night shift upon leaving at 11:30 P.M. It was customary for the night shift to leave compressed air blowers open at bottom of abaft until the compressor was shut down slightly before midnight. Presumably this was not done on the night of the lath as the fumes were so heavy in the shaft bottom on the morning of the 14th that at about 8 o'clock, Superintendent Bergen and one of the shaft men, on reaching the shaft bottom, were overcome and fell from the bucket into the sump containing about six feet of water; and when two other men went down in the bucket a few minutes later to investigate, one also fell into the sump and the other was barely able to roach the shaft collar. The three bodies were later on recovered from the sump.At 400 P.M., June 10, 1920, at the Dominion Mine, Colville, Washington, a round of 11 holes containing about fifteen pounds of 60 per cent nitro¬glycerine explosive was blasted in a fifty degree raise about fifty feet above the main tunnel level by the shift going off for the night. in this mine it was the practice not to try to blow out the fumes until just before the shift went to work the next morning, Although no work was being done on the night shift, one of the raise men, curious to ascertain the effect of the shots, about 7:45 P.M., wandered into the mine (which was a tunnel only a few hundred feet in length), and was missed by one of his companions about an hour later. When three men tried to remove the body of the inquisitive miner, two of them were also overcome; ultimately these two and the first man were removed from the point at which all were asphyxiated, which was practically at the foot of themaise."

Jul 1, 1920

By Spencer P. Hwell, Charles E. Munroe

"Among the surplus explosives left on band with the War Department was a quantity of that styled Trojan Grenade Powder, which was especially designed during the war for use as a bursting charge in grenades and for which naturally there would be very little military use in time of peace. With a view to its disposal through use in civil projects a quantity was sent to the Bureau of Minas explosives experiment station, where analysis showed that its characteristic explosive ingredient was nitrostarcn and that the powder bad the following composition:Trojan Grenade Powder appears as a dark gray granular substance, part of which is slightly pulverulent. The granules fairly hard. The explosive is not at all dusty, and has the consistency of granulated sugar.Nitrostarch is a substance produced by treating starch with nitric and sulphuric acids and in appearance it looks very little different from powdered starch. It resembles nitrocellulose and nitroglycerin in its constitution and explosive properties and has been longer known than either, it having been prepared by Braconnet in 1833. Nitrostarch explosives have in recent years been developed for industrial use in this country, they having been used to an extent in blasting in the Canal Zone, yet as this grenade powder was a special composition it seemed desirable that a complete series of tests should be run upon it. This was done, and the results are reported in the following table in comparison with those previously obtained in testing ammonia dynamite."

Jun 1, 1920

By Clyde E. Eilliams

In recent ye.ars much intere,t has been centered on the possibility of pro­ducing alumina from clq, a.nd proposed methods tor the recove:r,v of alumina are appearing constantly in parent lit,erature, As a good· grade of clay contains from 30 t<> 40 per cent of al"WDina, the prospect of tecovering it is alluring, al though obviously ditfieul t. A patent typical of m projected thermal processes is that 0£ Paul Migu.et, (U, S, Patent No, l,376,563) entitled nprocess for the preparation of pure alkaline alu:ninates.'' Re proposes to prepare alkaline a.luminate by fusing clay, lime, and acrap iron with a reducing aget in the electric furnAce, thereby reducing the silica a.r.d formin1s calcium alumina.te and ferrostlicon, The calcium aluminate, being lighter, would. float on top substantially free from foreign oxides, It could. then be tapped ott, cooledf ana later crushed and leached with aodium carbonate solution to torm, by double decomposition, sodium aluminate, and calcium carbonte. The fonMr is soluble and yields readily aluminum hydroxicie. 'l'he ferrosilicon wo'Uld be r,covered as such and sold at a profit.

Aug 1, 1922

By Frederick C. Trutt, Jeffery L. Kohler, Joseph Sottile

Twenty-five years ago, the former U.S. Bureau of Mines funded a research project aimed at developing the enabling technology for incipient failure prediction in electric power system components as a means of reducing the injuries and fatalities that sometimes occur when equipment malfunctions. Over the ensuing years, interest in this has waxed and waned, but recently interest has been growing for both civilian and military applications. This paper addresses the level of turn-to-turn insulation deterioration that can be resolved using an on-line monitoring technique. The detection of turn-to-turn defects is especially important because they are believed to represent the beginning stage of most motor winding failures.

By Dorsey A. Lyon, Robert M. Keeney

In the inquiries and investigations that the Bureau of Mines is making with a view to increasing safety, efficiency, and economic development in the metallurgical industries, the application of elec- tricity to various processes, and especially to those in the manu- facture of iron and steel, is being given attention. Some results of the work already done are presented in this bulletin, which gives a historical review of the development of electric furnaces for making iron and steel, and discusses the problems that remain to be solved in the use of electric furnaces for the smelting of iron ores and the production of pig iron at a profit on a commercial scale.

Jan 1, 1916

By G. B. Fritts, A. C. Moschetti

"INTRODUCTION The act of Congress establishing the Bureau of Mines in 1910 delegated to the Bureau, as one of its principal duties and functions, the study of health and safety in the mineral industries with a view to devising and putting into operation means of conserving the health and safety of persons employed in the industries. One of the first health and safety activities of the Bureau of Mines was therefore organization of a trained force to promote instruction in first aid in the mineral industries. First-aid training has been an important activity of the Bureau of Mines since its establishment. The standard first-aid course requires a minimum of 15 hours of instruction and practice work. A person completing the initial training course is issued an engraved certificate and pocket card certificate; thereafter, only a pocket card certificate is issued for additional training.From 1910 to 1926 first aid was taught by trained Bureau of Mines employees; consequently, only a comparatively few persons were trained. In 1926, however, cooperative first-aid training was initiated, which provided the means to train the entire personnel of mines or plants within a short time in a single campaign. Many mines and plants have taken advantage of the cooperative plan, whereby keymen in a mine or plant, in addition to the initial training received, are given intensive training in first aid by a Bureau of Mines instructor. Those men who show an aptitude for teaching are selected as tentative provisional first-aid instructors. In order to qualify as a provisional instructor, a tentative instructor must, under the supervision of a Bureau of Mines instructor, train a class of at least six persons employed in the minerals industries in the standard Bureau of Mines course in first aid. After it has been determined that the class has been trained properly, a provisional first-aid instructor's pocket card certificate is issued to the class instructor. The first-aid instructor can renew his pocket card certificate each year by training or retraining at least six persons connected with the mineral industries to satisfactorily pass an examination given by a Bureau of Mines representative. After five yearly renewals of a provisional instructor's pocket card certificate, an engraved, permanent instructor's certificate and a permanent instructor's pocket card certificate are issued to the instructor."

Feb 1, 1955

By L. C. IlsLey

It is most unfortunate that a few must often suffer , and perhaps die , that many may benefit from a fuller appreciation of the dangers surrounding mining operations , and the proper use of safeguards designed to offset these dangers . This has been the case during the last few months in the anthracite field , where several explosions , resulting in burnings and fatalities , were undoubtedly caused by the use of defective or improperly assembled flame safety lamps . Had this same lack of understanding regarding the proper assembly of this safety device , and had the same indifference on the part of the user in keeping the lamps locked at all times and in proper condition , been permitted in a region where the coal dust was explosive , a terrible disaster would surely have resulted . In nearly every coal -mining country , including the United States , the Davy and Clanny type of lamp has been superseded , and rightly so , by some kind of bonneted lamp . Bonneted lamps , especially of the naphtha type , while much safer than the unbonneted , have more parts and need more care in assembling . For this reason the burden of responsibility for their being properly assembled rests with the lamp man ; therefore , it is extremely important that only competent , conscientious men be given this work .

Dec 1, 1921

By H. H. Stoek

It would permit coal mines to operate continuously instead of intermittently . Intermittent operation increases the cost per ton for mining , and makes the yearly return to labor low . These conditions contribute to serious instability and unrest in one of the fundamental industries of the country and this can be changed only by coal buyers doing their part to insure steady work . The railroads are now required to transport the maximum amount of coal during the winter months when traffic is most interfered with by bad weather and when the maximum amount of coal is used by the railroads to handle other coal . The railroads now use nearly 30 per cent of the total output of coal . About one- third of their freight traffic is hauling coal , so that economy of fuel used by the railroads will produce a considerable gross saving .

Apr 1, 1920

By C. B. Manula, R. L. Sanford, R. A. Rivell

Development of the Rail-Haulage Sub-assembly for the Production Sub-system (UGMHS)* required the use of ,a newly formulated model in order to best satisfy the requirements. Many of the ideas of the former single-stage rail simulator included in the original version of UGMHS have been used, together with the results of experience gained in applying the earlier model to a variety of operating situations (Sanford, 1969). The sub-assembly is developed as an independent system and, as such, can be used to analyze track systems using production distri¬butions as data input. In addition, since this model is designed to replace the original sub-assembly in UGMHS, the linking procedure is identical with respect to bi-directional information flow. The flow of coal from production sections, for example, fills the mine cars, but a condition of "out of empties" or "full of loaded" at a loading station will shut down inby production sections. A requirements analysis was conducted to determine specifically how the model could best serve the user. Operating management had the largest input in developing the following requirements for the Rail Sub-assembly: a) data input in mixed narrative - numeric form to permit user identification of the input variables; b) a user option to extract several ranges of detail in model output, i.e., an average shift summary of minimum retrieval

Jan 1, 1974

By Van H. Manning

Of all the war work by the Bureau of Mines none ultimately covered such a variety of processes and equipment, employed as many men, or called for as large an outlay as that started in con- nection with the solution of problems relating to the use of noxious gases in warfare. Beginning with an investigation to develop the best type of gas mask, the scope of the work extended until it included researches relating to a wide range of devices, such as different types of poisonous and irritating gases and smokes, smoke screens, gas shells and gas bombs, flame throwers, trench projectors for firing gas bombs, signal lights, and incendiary bombs. The Bureau of Mines in starting this work selected the necessary personnel, pro- cured the early equipment, and for some months, from the begin- ning to June 30, 1917, paid the cost of the work from its own funds. The Bureau of Mines built up a research staff of more than 700 chemists, including many of the most prominent chemists in the country, and obtained the cooperation of many of the universities and chemical companies. When the results obtained through this research were to be applied by the War Department, the Director of the Bureau of Mines cooperated in the selection of men to have charge of manufacture or further development, recommending chemiste who subsequently received commissions in the Army. The personal cooperation with the War Department was thus very close. The bureau can fairly claim that because it started this work on gas warfare and received the hearty support of the Department of War, the Navy Department, the National Research Council, and State, educational, and private institutions, the country was in July, 1918, months ahead of where it would otherwise have been in the production of gas masks and other devices. The production of toxic gases then far exceeded the supply of shells. In addition the later work in gas-mask manufacture by the Surgeon General's Office of the Army, which resulted in the development of the best mask produced anywhere; in gas manufacture and gas proving-ground tests by the Bureau of Ordnance, and in the chemical warfare pro- gram of the Navy, including the use of smoke screens, shells and toxic gases, were the direct results of the bureau's experimental work. The American charcoal and soda lime, developed through the research work, are the best used by any nation. The Bureau of Mines was instrumental in developing satisfactory methods of manu- facturing chlorpicrin, phosgene, mustard gas, brombenzylcyanide, cyanogen chloride, and other noxious substances on a large scale. The bureau also developed a smoke funnel for the Navy which no doubt saved many ships from submarine attacks, and devised smoke barrages, signal lights, incendiary darts, etc., for the Army. The Ordnance Department of the Army asked for incendiary bombs and were furnished with bombs better than any made previously. Perhaps the greatest single result of the research work has been the demonstration of the value of the services that the chemist and chemical engineer can render in time of need and the recogni- tion of chemical investigations as a necessary function of the Gov- ernment.

Jan 1, 1919

By J. W. Thompson

The Sullman, Picard & Ballot patent, No. 835120, is a process of concentrating ore which consists in mixing the powdered ore with water, adding a small proportion, a fraction of 1 per cent on the ore, of an oily liquid having a preferential affinity for metal- liferous matter, agitating the mixture until the oil-coated mineral matter forms into a froth and separating the froth from the remain- der by flotation. The process is known as an air-flotation process which consists in the use of a frothing agent in conjunction with such agitation of the ore pulp as will distribute the metallic particles of the ore throughout the mixture and produce bubbles of air and bring them in contact in the mixture with the metallic particles so dis- tributed. The bubbles will become attached to such metallic par- ticles, carrying them separately from the particles of gangue up through the surface of the mixture where they can be readily collected by skimming, by overflow, or by the use of other well-known devices. The air-flotation process was a patentable invention in the discov- ery made in March, 1905, and was not anticipated and is valid. Prior to that time there had been no suggestion in the arts that a propor- tion of 0.1 per cent of oil to ore or of any other fraction of 1 per cent of oil to ore would or might result in successful concentration. While the ascertainment that such a minute proportion of oil would affect a successful concentration of ore through a flotation process was a discovery, it was nevertheless of such a character, viewed with respect to the circumstances under which it was made, as to involve inven- tion and confer patentability. Claims 1 and 12 of the Sullman, Picard & Ballot patent, No. 835120, for a process of concentrating ore, known as the air-flotation process, are valid; but claim 9 is so indefinite as to render the claim void. The object of the Sullman, Greenway & Higgins patent, No. 962678, dated June 28, 1910, for improvements in ore concentration, is to separate metalliferous matter, graphite, and the like from gangue by means of oil, fatty acid, or other substances which have a prefer- ential affinity for metalliferous matter over gangue, and it is valid. The Greenway patent, No. 1099699, dated June 9, 1914, for improve- ments in the concentration of ores is invalid, as in view of the prior art the omission to use acid in the process can not confer patenta- bility.

Jan 1, 1917

By N. S. Dalal, B. Jafarl, M. M. Suryan, V. Vallyathan

"The biologic events leading to coal workers' pneumoconiosis (C'WP) are not yet fully understood. There is no good correlation between toxicity studies or animal models with human epidemiologic and pathologic data. Several studies have shown that the severity and prevalence of the CWP in miners correlate strongly with the rank and type of the coal mined. However this has not been found to be the case with laboratory animal models or in vitro studies. In 1980 Russian scientists Artemov and Resnik suggested that the discrepancy may be related to the excessive amount of short-lived free radicals present in freshly generated coal mine dust. Because of their short life, such free radicals would be absent in the ""stale"" coal dust used in most animal experiments. To test this hypothesis we have undertaken a systematic study of the generation, reactivity with oxygen and biological significance of free radicals in coal dust.Electron spin resonance (ESR) was used as a technique for the direct detection of radical production and kinetics of decay. ESR signals from the newly generated radicals decreased with time on exposure to oxygen or when stored in biological buffers at a rapid rate. In vitro biological tests were carried out which suggest that the reaction between the newly generated radicals and oxygen plays a significant role in the sample's cytotoxicity.Materials and MethodsESR measurements were made at X-band (~9.7 GHz) using a computer-controlled Bruker ER200D ESR spectrometer. 11te two coals studied in detail were obtained from the Pennsylvania State University Coal Depository. These were, a bituminous sample, PSOC-1172 (72% carbon) and an anthracite sample, PSOC 867 (95% carbon). Coal particles of several millimeter (mm) dimensions were evacuated to a pressure of ~10-3 mm Hg typically overnight. Without exposure to air, these particles were ground in an agate mortar with an agate pestle for about 30 minutes and then sieved through a 20 \1111 mesh filter before ESR measurements or cytotoxicity studies. As an index of cytotoxicity, hemolysis was measured according to the method of Harrington, with minor modifications. Sheep erythrocytes (2%) were incubated with test samples at 37°C for one hour, and the hemoglobin released was quantitatively estimated photometrically. Additionally, release of alveolar macrophage enzyme lactate dehydrogenase (LOH) was estimated after incubation of the macrophages with the coal particles at different time intervals after the grinding. Enzyme activity was assayed according to the method of Wrobleski and LaDue and expressed as percent of enzyme released in 2 hours per million cells with 1 mg of coal."

Jan 1, 1989

By GEORGE S. POPE

The purchase of coal by the Government under specifications depending on the heating value of the coal, its content of ash and of moisture, and other considerations, rather than upon the reputation or trade name of the coal, was based on the fuel investigations begun by the Technologic Branch of the United States Geological Survey in 1904. The plan was first adopted by the Treasury Department in 1906. Since then the plan, variously modified in form but the same in principle, has been gradually adopted by other departments until at present of the coal used by the Government, the total value of which approximates $8,000,000 annually, more than half is purchased under specifications. The Government publications dealing with the adoption by the Government of the specification plan, the number of contracts awarded on that basis, and the quality of the coal delivered under such contracts in the several fiscal years covered by the reports are given in publications listed at the end of this bulletin. Under the authority of acts of Congress making appropriations for analyzing and testing fuels belonging to or for the use of the United States Government, a laboratory is maintained at the headquarters of the Bureau of Mines, Washington, D. C., where samples represent- ing deliveries of coal purchased under specifications for Government use are analyzed and tested. At this laboratory more than 1,200 samples have been analyzed and tested in one month. With the complete equipment and the efficient force employed, the analytical work has been so perfected that the analyses and heating-value tests of the samples received are as accurate as may be reasonably expected in laboratory work of this nature. One of the serious drawbacks to the general adoption of the speci- fication method for the purchase of coal is the difficulty of obtaining at reasonable cost samples of coal that can be considered fairly repre- sentative of the commercial product delivered in wagons, railroad

Jan 1, 1913

By W. P. Yast, R. R. Slyers, J. H. Hildebrand

 The Bureau of Mines, in conducting investigations of atmospheres in mines and tunnels for the purposes of determining and combating hazards to the health and safety of workers, has from time to time closely cooperated with municipal, State and Federal agencies in safety work in engineering and ventilating probleme. Recently the writers have conducted experiments with animals and men breathing helium-oxygen mixtures under pressure. The object of this work was to determine whether helium-oxygen atmospheres can be utilized to advantage in place of normal air for caisson and diving work. In such work the permissible pressures and times of compression and decompression are limited by the physiological effects on man. The major effect is that the nitrogen, (which is the inert con- stituent of normal air and is absorbed by the body tissues and fluids in abnormal amounts when under pressure,) tends to form bubbles in the tissues on too rapid discompression from high pressures. The Bureau of Mines is interested in this problem on account of the pos- sibilities of mitigating caisson illness in tunnel construction and other engine eering operations requiring men to work in compressed air. In addition, the Navy Department is interested on account of the possibilities for extending the range of salvaging and marine engineering operations. The results of the experiments conducted by the writers lead to the following conclusions: Helium is without odor or taste and has physical properties which promise to be of interest physiologically and which have been found to have possibilities of creat practical use, especially in making a synthetic atmosphere that will re- duce the hazard of caisson disease. The substitution of helium for the nitrogen ordinarily present in the air we breathe has been found to result in an atmosphere which it as respirable as that provided by nature. The results obtained indicate that helium not only has the advantage of being less soluble than nitrogen, but

Feb 1, 1925

By Bruce K. Cantrell, Stephen W. Stein, Kenneth L. Williams, David Hassel, Harvey Patashnick

In June 1992, the Mine Safety and Health Administration (MSHA) published the "Report of the Coal Mine Respirable Dust Task Group, Review of the Program to Control Respirable Coal Mine Dust in the United States." As one of its recommendations, the report called for the accelerated development of two mine dust monitors: (1) a fixed-site monitor capable of providing continuous information on dust levels to the miner, mine operator, and to MSHA, if necessary, and (2) a personal sampling device capable of providing both a short-term personal exposure measurement as well as a full-shift measurement. In response to this recommendation, the National Institute for Occupational Safety and Health (NIOSH), Pittsburgh Research Center, initiated the development of a fixed-site machine-mounted continuous respirable dust monitor. The technology chosen for monitor development is the Rupprecht and Patashnick Co., Inc. tapered element oscillating microbalance. Laboratory and in-mine tests have indicated that, with modification, this sensor can meet the humidity and vibration requirements for underground coal mine use. NIOSH is continuing that effort by developing prototypes of a continuous dust monitor based on this technology. These prototypes are being evaluated in underground coal mines as they become available. This effort, conducted as a joint venture with MSHA, is nearing completion with every promise of success. The immediate benefit of this effort will be to researchers, regulatory personnel, and mine personnel, by permitting evaluation of specific mining practices to see which expose mine workers to excessive dust levels. Using this information, mine personnel can optimize mining procedures to reduce dust exposure. MSHA and the operators will also be able to use the dust concentration data to judge whether dust plan parameters are adequate to continuously maintaining environmental dust levels below the applicable standard. The second development recommended by the Dust Task Group was a person-wearable version of the continuous dust monitor. It will be a monitoring system designed to provide a measurement of worker exposure to respirable dust, both during and at the end of the shift.

By E. P. Youngman

The law now in effect (January 30, 1931) in the Netherlands with respect to the prospecting for and the developing of minerals is regulated by , or based upon , the French Act of April 21 , 1810 , "Concernant les mines , les minières et les carrières ( Bulletin des Lois No. 285) . " A second edition of a compilation ( by Drs . Ccuvee and Ritter ) of the mining legislation of Holland , including this act with other legal requirements , was published in 1928 under the title of "De Nederlandsche Mijnwetgeving , " by H. T. Tjeenk Willink & Zoon , Haarlem. In this abstract reference is made to the Act of 1810 , the Royal Decree of September 18, 1818 , the Mining Act of 1903 , and the Act of June 20 , 1924 .

Aug 1, 1931

By J. Douglas Causey

In 1985, at the request of the Bureau of Land Management, the U.S. Bureau of Mines studied a portion of the 110,000 acre Massacre Rim Wilderness Study Area (CA-020-1013). The area studied, containing 23,260 acres, is located in northwest Washoe County, Nevada, about 25 miles west of Vya adjoining the Charles Sheldon National Wildlife Refuge. Basalt caps older tuffaceous sedimentary rocks in an area that contains no claims or prospects. No mineral resources were identified during this investigation.

Jan 1, 1987