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By G. M. Molinda, J. P. Ulery

Since 1970, abnormally high methane emissions have been observed in eastern sections of the Federal No. 2 Mine operating in the Pittsburgh Coalbed in northern West Virginia. The nature and volume of these emissions indicate a source other than the coalbed. An investigation was undertaken to delineate probable methane sources. Gas well information and stratigraphic correlation of corehole data indicates that a sandstone directly above the main coalbed is an additional source of methane emissions. The sandstone body appears to be an ancient stream channel, infilled with fine-grained sand and organic matter. Coalification of the organic matter produced methane as a byproduct. Additional methane presumably migrated into the sandstone unit from the subjacent coalbeds. The methane became trapped in the porous clasticunit by the surrounding impermeable strata. Mine development near this unit creates a significant pressure gradient, triggering abnormal methane emissions into the mine along naturally occurring fractures. Pre-development methane drainage of the sandstone could be accomplished by completing vertical boreholes along its trend.

Jan 1, 1984

By Audrey F. Glowacki, August J. Kwitowski, Richard L. Unger, Edward F. Fries

Well-prepared personnel and an effective emergency response plan are essential components of any emergency command center. Unfortunately, evaluating emergency preparedness is often difficult until a disaster actually occurs. For example, unexpected events may develop during an emergency that were not considered during the planning phase. Also, the command center may need to cooperate with organizations that it has not worked with previously. Preparation can be especially difficult for smaller or remotely located command centers, or those with limited resources to conduct mock drills. This paper explores the potential of using the Internet to teach and evaluate command center skills. The National Institute for Occupational Safety and Health (NIOSH) is developing an Internet-based, computer simulation training package for the mining industry. Trainees will play the role of command center leaders at a mine, while the actions of other individuals and organizations are simulated. Trainees will be able to test their emergency response plans and learn valuable lessons from past mine emergencies. Nationally recognized experts will be able to create new training scenarios and make them available to mines throughout the U.S. This product should better prepare command center personnel for large-scale disasters such as fires and explosions. Keywords: emergency preparedness, simulation, training, internet

By Richard A. Winters

In 1985 at the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied 9,400 acres of the 10,005-acre Duncan Creek Wilderness Study Area (ID-111-78) in order to evaluate the mineral resources. The study area is located in Owyhee County, 10, about 36 miles southwest from Bruneau, ID. No mining districts are in the study area, nor were any mines or claims recorded or found. The southern half of the area was covered by oil and gas lease applications, all of which were cancelled prior to June, 1985. No economic concentrations of minerals were found in the study area. INTRODUCTION This report describes the USBM (U.S. Bureau of Mines) portion of a cooperative study with the USGS (U.S. Geological Survey) to evaluate mineral resources and potential of the Duncan Creek study area at the request of the BLM (U.S. Bureau of Land Management). The USBM examines individual mines, prospects, claims, and mineralized zones, and evaluates identified mineral and energy resources. The USGS evaluates potential for undiscovered resources based on areal geological, geochemical, and geophysical surveys. Results of the investigations will be used to help determine the suitability of the study area for inclusion into the National Wilderness Preservation System. Although the immediate goal of this and other USBM mineral surveys is to provide data for the President, Congress, government agencies, and the public for land-use decisions, the long-term objective is to ensure the Nation has an adequate and dependable supply of minerals at a reasonable cost.

Jan 1, 1986

By F. J. Gallagher

Some serious fires have occurred in bituminous-coal mines because of short circuits on direct-current power systems that do not have adequate circuit-breaker protection. The writer's observation of circuit-breaker installations in numerous coal mines leads to the conclusion that many persons am not properly informed as to the true functions, limitations, and operation of circuit breakers. Faulty protection results in fire hazards that endanger lives and property. Proper circuit-breaker protection would greatly minimize or, in many instances, eliminate the hazards; moreover, many operating advantages of proper application of modern circuit breakers would be gained. The purpose of this circular is to show why fire hazards exist in many mines despite the use of circuit breakers and how, the hazards may be overcome. A method is given for determining whether additional circuit-breaker, protection is required for a specific 250/275-volt direct-current distribution system, and, if so, the approximate locations and capacities of the required supplemental breakers.

Jan 1, 1951

By R. S. DeCesare

Operation of the Bureau of Mines raw refuse continuous separation pilot plant is described, including modifications made to plant equipment for improved performance. Products recovered from refuse, many of which have been evaluated by other laboratories and private firms, are discussed. Sampling procedures used in the pilot plant and detailed data obtained from processing refuse from 13 municipalities are presented in appendixes. Fuel evaluations made on combustible fractions of refuse from the various municipalities are also presented. Information and data obtained at the pilot plant have been used to assist many municipalities in solving their urban refuse problems.

Jan 1, 1980

By H. R. Beard

The Federal Bureau of Mines investigated the absorption of radium and thorium from waste uranium leach liquor by clays and other materials. This work was conducted in support of the Bureau's goal of minimizing the environ¬mental conflicts, impacts, and occupational hazards Associated with mining and mineral processing operations. Tailings and soil samples from Wyoming and Utah were contacted with tailings liquors to determine the degree of absorp¬tion. Absorption ranged from 0 to 99 percent for radium and from 0 to 31 per¬cent for thorium. Some samples, which readily absorbed radium, were contacted with various salt solutions that could be present in tailings solutions to determine their effectiveness as desorbents. The desorption of radium ranged from 0.06 to 100 percent. An alpha-spectrometric method was used to determine the radium and thorium, concentrations in the solutions and the solids.

Jan 1, 1979

Design a model health and safety program which, when implemented, can improve mine safety by reducing occupational injuries and accidents. Approach The Bureau of Mines developed a model program which identifies the elements essential to the effectiveness of health and safety programs designed for mining operations, and is readily adaptable to all types of sizes of mines. The model program primarily provides training on loss control and accident investigation and technical assistance with health and safety problems. In order to assess the effectiveness of the program, it was tested at both a coal and gold mining operation. Monthly statistics were generated to reflect the number of occupational injuries and accidents, and the severity of injuries (as measured by the number of work days lost during recovery). Observations were made of employees performing a large number of randomly selected jobs in order to estimate. the proportion of the workforce that was working in the presence of one or more of three types of safety deficiencies: Type A-individual job performance deficiencies which could be corrected by the employee alone I e.g., an employee is seen not wearing a seatbelt.

Jan 1, 1986

By N. E. Hanna

The effect of small percentages of sodium chloride on the incendivity of permissible explosives was studied by the Bruceton up-and-down technique in gallery tests. Both the reduction in incendivity achieved by addition of sodium chloride and application of the test method to explosives evaluation are discussed. It is demonstrated that the up-and-down technique in gallery testing is suitable for distinguishing differences in incendivity between different explosive compositions and between lots of the same composition. The study also shows that addition of relatively small quantities of sodium chloride tends to reduce the incendivity of explosives to firedamp, but addition of sodium chloride cannot insure reduced incendivity. Any improvement attributable to the salt can be counteracted by undefined variations in the explosive. The need for experimental investigations of a number of factors that may affect the safety of permissible explosives is emphasized. ACKNOWLEDGMENTS Grateful acknowledgment is made of the assistance of Roy L. Grant in analyzing for normality of distribution of the data obtained by the up-and-down methods and to Harold E. Tubbs for numerous calculations.

Jan 1, 1959

By Paul A. Pierce

In 1984, the Bureau of Mines evaluated an area previously identified as having "probable mineral resource potential" for copper, lead, zinc, gold, or silver within the Elkhorn Wilderness, about 5 miles west of Winston, MT. The purpose of this study was to determine whether the mineralized structures at nearby mines and prospects outside of the Wilderness extend into and contribute to the anomalous zone and, if so, to expand the domestic supply of strategic and critical mineral resources for future needs by identifying and quantifying resources on public lands. Fifty-eight soil samples, 23 rock samples, and 1 stream sediment sample were collected in the Staubach Creek area. Overall sample analyses suggest the anomalous zone in the Staubach Creek drainage is possibly associated with -.mall pyritiferous quartz veins. These veins or veinlets may be part of a system of northeasterly-trending structures prevalent in this art of the Wilderness. However, there is not sufficient evidence to prove that identified resources outside of the Wilderness extend into it in the Staubach Creek drainage, or that economic base- or precious-metal deposits are likely.

Jan 1, 1987

By L. M. Irwin

This Bureau of Mines investigation relates the physical properties of copper reverberatory furnace slags to changes in composition, The smelting of upper Michigan copper ore presents some problems that probably differ from those of other copper smelting areas. The study of these problems has, however, provided important data regarding slags in general and therefore will be of value to other operations as well. Conclusions reached from this study were: (1) Slag fluidity and refractive indices varied directly with the iron content and inversely with silica, lime, and alumina, and (2) there was no apparent correlation between slag fluidity and its copper content.

Jan 1, 1962

By James R. Boyle

The value of mineral production in-creased 13% in 1977. Nearly all commodities registered an increase in production and value, continuing a trend that started in 1976. In addition, practically all commodities registered an increase in unit value. Alabama led the Nation in the production of crushed marble, was second in bauxite and scrap mica third in kaolin and oyster shell, and fourth in bentonite, dimension marble, and fire clay.

Jan 1, 1981

By W. W. Adams

"Fatal accidents at coal mines throughout the United States killed 234 employees during January 1924, according to reports from State mine inspectors to the Bureau of Mines of the Department of the Interior, Included in the number of fatalities are 68 deaths caused by two explosions during the month, one explosion occurring in a mine at Johnson City, Ill., and causing 32 deaths, and the other in a mine at Shanktown, Pa., and causing 36 deaths. The fatality rate for the month was 3.94 per million tons, based on a production of 59,435,000 tons of coals In January 1923 the fatality rate was 3.52, based on 206 deaths and an output of 58,458,000 tons.Bituminous mines in all States reported 202 fatal accidents, the production being 51,170,000 tons., and the fatality rate being 3.92, as compared with 3.28 for January last year, For the anthracite mines in Pennsylvania, the reports covered 32 fatalities, which, on the month's output of 7,955,000 tons, indicated a fatality rate of 4.02 per million tons, as against 4.89 for January 1923.As compared with January 1923, the reports for January of the present year indicated lower fatality rates per million tons for all of the main causes of accidents except explosions. For falls of roof and coal, the fatality rate per million tons declined from 1.85 in January 1923 to 1,68 in January 1924; for haulage accidents the rate declined from 0.62 to 0.42; for explosives, from 0.19 to 0.12; for electricity, from 0.12 to 0.07. The rate for explosions increased from 0.21 to 1,31 per million tons. -- Reports of Investigations, Department of the Interior, Bureau of Mines."

Feb 1, 1924

By E. William Rossi, Sean Gallagher, Richard L. Unger

The purpose of this study was to examine the lifting capacity of low-seam coal miners in four restricted work postures (roof heights of 36", 40", 44", and 48"), investigate the associated metabolic costs, and to examine electromyographic (EMG) data from eight trunk muscles during the lifting procedure. Subjects were thirteen underground miners accustomed to handling materials in restricted work postures. Each subject performed two twenty-minute periods of asymnetric lifting in each of four postures during the day of testing. The. frequency of lifting was 10 lifts per minute. A specially designed lifting box incorporated microswitches in one handle of the box and another in the bottom of the box, in order to examine the trunk muscle function at specific points during the lfting cycle. The data collected will be used by the Bureau of Mines to make recommendations for lifting materials in low-seam coal mines.

A computer program for the static load analysis of linear elastic structures is presented. It is the product of a two-year project for the development of a efficient program for the analysis of mine-type structures. The report is divided into two parts. The first part explains the general method of analysis, the computer program organization and the most significant numerical techniques used. The second part is a user manual for the computer program. The FORTRAN IV computer program deck and example problems were transmitted separately to the sponsor. Request for a copy of the program should be directed to the Bureau of Mines, Denver Mining Research Center.

Jan 1, 1972

By D. E. Seizinger

The Bureau of Mines has developed analytical methods, primarily gas chromatographic, for measurement of exhaust oxygenates produced from selected simple fuels. The resulting data were used to estimate levels of carbonyls and noncarbonyl oxygenates in exhaust from gasoline fuels. Estimated noncarbonyl oxygenates in gasoline exhaust may comprise as much as 30 pct of total oxygenates which include unsaturated carbonyls and noncarbonyls believed to be significant potential pollutants.

Jan 1, 1972

By F. A. Rutledge

The Millet copper deposit is on the north shore of Iliamna Lake in southwestern Alaska. Copper mineralization occurs in a zone of altered limestone .adjacent to and intruded by a diorite porphyry with some diabase facies. During 1949 and 1950, the Bureau of Mines investigated this prospect as a part of the U. S. Department of the Interior program in Alaska for the development of critical and strategic minerals. Field work was begun August 8, 1949; it was recessed November 28, 1949, because of inclement weather. The work was resumed Nay 28, 1950, and completed July 3, 1950. The program of investigation by the Bureau of Nines included topographic surveying, machine and hand trenching, diamond drilling, and sampling the zones of mineralization. This report outlines the general geology of the area, gives a description of the deposit, and contains the factual data resulting from work by the Bureau of Mines.

Jan 1, 1952

By D. Randolph Berry

Volume II contains appendices which explain and document the recommendations of Volume I. The following topics are covered: Appendix A Discussion of Recommended Guidelines Appendix B Worldwide Use of Oxygen Self-Rescuers Appendix C Hypothetical Use of Oxygen Self-Rescuers in Post-1972 Coal Mine Explosions and Fires Appendix D Vibration Testing of SCSRs Appendix E Testing of In-Service Chemical Oxygen SCSRs Appendix F Discussions with Representatives of Underground Coal Mining Appendix G Recommendations for SCSR Storage Containers Appendix H Example SCSR Storage Plans Appendix I Testing of In-Service Compressed Oxygen SCSRs Appendix J 30 CFR 75.1714, 30 Regulations Pertaining to Self-Rescuers

Jan 1, 1981

By Stephen P. Signer

This paper presents an overview of laboratory and field tests on approximately 250 fully grouted roof bolts instrumented with strain gauges in order to study loading behavior. Laboratory work included pull tests, time-dependent tests, and shear tests. The field tests were conducted in 14 different mines extracting different commodities. However, because of the focus of this publication, only the results of tests in 9 coal mines are reported here. In the field tests, all but 14 bolts were loaded by rock movement; these 14 bolts were tested using pull gear. The variables studied included anchorage length, mechanical interlock, time-dependent behavior, shear, installation load, loading rate, and maximum load level. Such information will improve the understanding of the behavior of resin-grouted bolts, which in return will enhance the safety of miners by reducing the occurrence of rock falls. The influences of geology, overburden depth, entry width, mining-induced stresses, and bolt spacing are not described.

Jan 10, 2000

By l.J Prosser

from 1990 to 1996, 16 states reported 92 injuries from falls of roof, rib or face in the more than 90 underground stone mines in the United States (Fig. 1). Missouri, Pennsylvania and Kentucky accounted for 48% of the total number of injuries (Fig.2). Of this total, 11 miners were killed. Of the 11 fatalities, 10, or 91 %, were associated with unrecognized loose or failed rock within the roof beam. Additionally, unrecognized roof beam failures resulted in a majority of the falls of ground injuries occurring in underground US stone mines from 1990 to 1996.

By Donald O. Capstick

In 1981, U.S. Bureau of Mines personnel conducted a survey of claims and prospects in the Wheeler Ridge RARE II area to determine if mineral resources or potential for resources exists at deposits in the area. Results of Bureau of Mines investigations indicate the area contains no identified mineral deposits. However, the geologic setting at the Round Valley Peak Prospect near the center of the study area is considered to be favorable for the discovery of tungsten resources with associated molybdenum and copper. Tungsten deposits, should they be present, would be expected to occur at depth in tactite at or near the calcareous rock-granite intrusive contact. Sand, gravel, and stone deposits in the area are not considered to be resources because equal or better quality material is available closer to major markets. INTRODUCTION The 16,200-acre (6,560 ha) Wheeler Ridge study area is 11 mi (18 km) northwest of Bishop, California, on the eastern flank of the Sierra Nevada range. The John Muir Wilderness adjoins the study area's western boundary (fig. 1).

Jan 1, 1983