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By James R. Boyle

The value of Alabama's nonfuel mineral production in 1983 was $361.3 million, an increase of $61.9 million over that of 1982. The increase reversed a downward trend that started in 1980 and established a new record high for value of nonfuel minerals in the State. Output of most nonfuel minerals increased to some degree with unit value increases creating the record-high value year. Cement, clays, lime, sand and gravel, and crushed stone were the major commodities produced in Alabama. Alabama led the Nation in the production of crushed marble; was second in bauxite; fourth in ferroalloys, dimension marble, common clay, and fire clay; fifth in bentonite and kaolin; and sixth in masonry cement and lime.

Jan 1, 1985

By S. M. Shelton, W. A. Calhoun

"INTRODUCTION Discovery and development of a southwestern Arkansas quicksilver district are recent history. In July 1930 4/, a specimen was discovered near the Little Missouri River in sec. 1, T. 7S. R. 26 W., which was identified as cinnabar. In the summer of 1931, Leo Yount began prospecting for cinnabar near the Little Missouri River. In the fall of that year he operated a small three-tube retort near the present Parker Hill mines and produced several flasks of quicksilver. Yount optioned a considerable block of ground containing the best showings in the Little Missouri River area, and on February 19, 1932, he and W. C. McBride, Inc., of St. Louis, Mo., formed the Southwestern Quicksilver Co., which was the largest producer in the district until operations ceased in September 1934.The Southwestern Quicksilver Co. installed a rotary furnace on Parker Hill in April 1932, which treated ore from the three principal mines Gap Ridge, Parker Hill, and Parnell Hill. In 1934 production was entirely from the Gap Ridge and Parker Hill mines. Nothing was done at Parnell Hill except a little small-scale work on a share basis.Mercury Producers, Inc., later took an option on the holdings of the Southwestern Quicksilver Co. and in June 1935 began operations. The company produced considerable quicksilver before the lease and option were surrendered in the summer of 1936. Most of the work of Mercury Producers, Inc., was on Parnell Hill, but some work was done on Parker Hill and at the Bell prospect on ground not controlled by the Southwestern Quicksilver Co."

Mar 1, 1942

By J. E. Chilton

A technique for use in underground coal mines measures the response times of machine-mounted methane monitors. This technique uses a calibration cup to deliver gas to the sensor head to measure response times. For comparison, in the current study, response times were measured by placing methane sensor heads in a specially designed test box where they were exposed to an atmosphere containing a constant concentration of methane. Response time readings measured in the test box were shorter than the readings obtained using the calibration cup. The response times measured in the test box were comparable for sensors from three different manufacturers. The effects of dust cap and flame arrestor design on response times were also evaluated using the test box.

This report describes the activities and publications of the Bureau of Mines Health and Safety Research and Testing Center, Pittsburgh, Pa., for the fiscal years 1960-65. It includes a discussion or work being conducted on roof control, dust explosions, ventilation, health, coal mine fire control, and electrical-mechanical testing, and an abstract of each paper published during the report period.

Jan 1, 1966

By Joseph P. DuCarme

The U.S. Bureau of Mines explored new methods and technology for extracting coal from the Appalachian Mountain region of the Eastern United States. These methods were aimed at extracting coal from thin seams and focused on the use of "roof-fall-tolerant" (RFT) mining concepts. These methods could be used on existing, abandoned highwalls or in conjunction with new highwall mining. The research was conducted using small-scale and quasi-full-scale physical models to obtain experimental results. Details are provided on (1) the quasi-full-scale model for cross-ridge mining, (2) the quasi-full-scale model for down-ridge mining, (3) the test results of these models, and (4) recommendations for future research. Significant results include demonstration of the RFT concept, a discussion of expected coal produced from these methods, and recommendations for future research.

Jan 1, 2010

By Lars G. Olavson

A prototype roof bolt which can be remotely placed by pumping has been developed by the Bureau of Mines. It is known as the "Pumpable Bolt". With the objective of field testing the effectiveness of the pumpable Bolt roof support system a mining machine was developed capable of installing Pumpable Bolts in the normal production cycle of a typical underground coal mine. The machine was built and the pumpable Bolt concept tested and evaluated as a total system in shop and mine tests. The machine was operated in the mining cycle of two mines and pumpable Bolts were installed at both mine sites.

Jan 1, 1976

Reduce the danger to personnel and destruction of equipment caused by fires on surface coal augers. Approach: A reasonably priced reliable system which automatically senses a fire and activates dry chemical extinguishers, has been built and field tested. How It Works: Heat sensors mounted in the engine compartment and hydraulic hose areas detect the fire, usually before the operator does. This causes the system to automatically discharge A-B-C class dry chemical extinguisher through a fixed piping system.

Jan 1, 1976

Objective: To help prevent squeezes, collapses, and other pillar failures through better pillar design, thereby enhancing safety for underground mine workers.

Jul 1, 1997

By Michael J. Friedel

As part of an investigation aimed at mitigating the hazards caused by abandoned mine openings, the Bureau of Mines conducted a series of electromagnetic surveys in the Galena, KS, area of the Tri-State mining district. The application of monostatic ground-penetrating radar (OPR) and inductive electromagnetic methods for detecting and delineating hazardous mine openings and attendant features was demonstrated to be feasible for shallow mine workings (i.e., less than 35 ft) occurring below flat-lying areas. Accurate determinations of depth to a mine roof appeared to be limited to roughly 20 ft using the GPR method. Features such as mine voids, fractures, and zones of subsidence were located beneath the Mainstreet (State Highway 26) site using the GPR system. Both the GPR and inductive electromagnetic techniques satisfactorily located mine openings and pillars at the Hell's Half Acre site. Geophysical interpretations were supported by exploratory drilling and mine maps.

Jan 1, 1990

By Wesley G. Holtz

A project to demonstrate the feasibility of retorting oil shale by the Paraho vertical retort process was carried out at Anvil Points, Colorado during 1974 to 1976. As a part of the demonstration project, laboratory and field tests were performed to determine the physical and chemical properties of the retorted shale for use in the development of eventual full-scale disposal plans. The material which exits from the Paraho retort is classified as a non-plastic silty gravel by the Unified Soil Classification System. The particles have an apparent specific gravity averaging near 2.60 and a mass specific gravity averaging near 2.00. The material can be compacted by normal laboratory and field construction methods to about 90 to 100 pounds per cubic foot dry density depending upon the degree of compactive effort applied. The addition of moisture does not improve compactibility appreciably. When high compactive effort is applied the retorted shale is classed as impervious to water flow. The compacted retorted shale exhibits shear strengths in the same order as those observed for silty gravel soils. If the compacted material is cured (long tune simulation testing) prior to strength testing considerable strength gain can be obtained from cementing action. The amount of cementing developed is dependent upon heat treatment and other operating modes of the retort.

Jan 1, 1976

By G. B. Sonneman

This final report summarizes the work done by The Bendix Corporation, Environmental Science Division, under contract to the Bureau of Mines to design, develop and test two improved systems for remote sampling the air at the working face of a coal mine in conjunction with approved portable methane detectors and machine-mounted methane monitors respectively. The work was started in May 1973 with preliminary design studies and was completed in May 1975. Five portable and two machine-mounted sampling systems were delivered. Contract "add-on" requirements for (1) modification of the machine-mounted system to accommodate a flame safety lamp and (2) a study of sensor response time improvement for the machine-mounted system were also completed.

Jan 1, 1975

By C. H. Kats, E. G. Meiter, J. J. Bloomfield

"INTRODUCTION.Street manholes for underground power and signal circuits, and for sewers vary in size from small openings that a workman can enter, to large central vaults. As the gas hazards in manholes are similar to those in mines, the mine safety committee of the Bureau of Mines was asked whether the miners' flame safety lamp is a practicable device for indicating inflammable gases in manholes.The coal miner detects firedamp (methane or CH4) with his flame safety lamp by observing the luminous can or the increased length of flame that appears when 1.5 per cent or more of the combustible gas is present. The lamp flame also warns him of lack of oxygen by going out when the oxygen becomes less than 16 to L7 per cent. A tentative rule regarding the proposed use of safety lamps at manholes has been suggested previously as follows: ""Testing for gas: Do not enter manholes until you have .assured yourself that the manholes are free from dangerous gases, by testing with an approved safety lamp, by ventilation, or by other adequate methods."" The Bureau's committee recommended that miners' flame safety lamps are not suitable,testing in manholes because hydrogen gas may be formed therein. The flame safety lamps approved by the Bureau of Mines for use in aseous mines are safe in presence of methane and while not tested against the members of the paraffin hydrocarbon series (CnH2n+2) higher than methane they been have been used therein; the lamps should not be used in hydrogen or acetylene they can initiate explosions in presence of these gases."

Oct 1, 1925

By Henry P. Chandler

TONNAGE of natural abrasives sold or used in the United States in 1959 increased 12 percent. Artificial abrasives produced in the United States and Canada jumped 24 percent. Imports, exports, and reexports of abrasive materials also showed gains. Sales of grinding wheels were up 33 percent and coated abrasives 17 percent. FOREIGN TRADE Imports of abrasive materials totaled $91 million, an increase of nearly 51 percent over 1958. Chief commodities contributing to [ ]

Jan 1, 1960

By Steven W. Schmauch

A mineral survey by the U.S. Bureau of Mines and U.S. Geological Survey indicate the Blanco Mountain RARE II area has low potential. Lode deposits consist of small, mineralized quartz or quartz-gossan veins. The veins are sparse and widely separated and lead, silver and gold content is restricted in amount and concentration. No gold or other potentially economic minerals were found in a placer deposit. There is no evidence of industrial mineral, geothermal, or energy resource potential in the study area. INTRODUCTION A mineral resource survey of the Blanco Mountain RARE II area (No. 5059), Inyo and Mono Counties, California was conducted in July 1981. This report summarizes the results and interpretations of the Bureau of Mines investigation.

Jan 1, 1982

By T. F. Mitchell, B. K. Shibler, J. V. Batty, W. G. Sandell, G. M. Potter

"INTRODUCTION The Park City district, situated 30 miles east of Salt Lake City, Utah, in the Wasatch Mountains, Is a well-known producer of lead, zinc, and precious metals. Nearly continuous production has been maintained from the dis¬trict since its early discovery about 1870. For approximately 50 years, gravity milling methods were employed to beneficiate Park City ore, and during that time tailings from the mills were sluiced down Silver Creek and deposited on lands below the camp for 7 miles.Owing to the large tonnage of tailings deposited along Silver Creek, considerable work was done in the past in the attempt to develop a low-cost concentration method for re-treating this material, but no-method was found that was economically feasible. The Bureau of Mines was asked to conduct beneficiation tests on Park City tailings in November 1944, and metallurgical studies were initiated at that time. This report summarizes the results of laboratory ore-dressing studies made on samples from the Grasselli deposit."

Dec 1, 1947

By R. D. Leitch

The work of the United States Bureau of Mines on stream pollution by coal-mine drainage has included a study of seasonal variations in acidity and volume of several streams in Pennsylvania. The acidity of these streams has been determined during the two or three years prior to 1930 and the results may be considered to represent "normal" low water conditions. The summer of 1330, however, was unusually dry and represents what may be termed "extreme low water conditions on these streams. This report is a comparison of the results obtained for extreme low water of 1930 and for other years. The streams investigated were Buffalo Creek in Somerset County, Indian Creek (lower 5 miles) in Westmoreland County, Little Toby Creek in Elk and Jefferson Counties, Daguscohonda Run in Elk County and West Creek in Elk and Cameron Counties. These will be treated separately in the order given. Most of the descriptive matter and physical data pertinent to the streams and drainage basins are taken from published reports of the Pennsylvania State Water Supply Commission, 1917.

Jan 1, 1931

By G. E. McElroy

[The ventilation of development faces in mines for diluting gas or dust concentrations aid in hot mines for providing air-motion cooling affect, by fan-pipe units discharging high-velocity streams of air close to the face, is an important phase of mitre ventilation. The effectiveness of such units depends largely on the air-flow distribution between-the pipe discharge said the face, a subject on which little definite information is available. A study of the air, flow from grills into rooms3/ has provided sore basic data, but under conditions so different from mine fan-pipe installations in development ends that tae data to are of doubtful application to mine installa¬tions, owing to differences in air-flow conditions. The purposes of this report is to present and discuss the results of an initial series of tests of a general investigation designed to yield definite laws and design data for the discharge of fan-pine lines in nines. The s series was planned to yield preliminary data on the effects of velocity of discharge, size and shape of tripe, and adjacent calls on the air-flow distribution. Tents were made on 10-inch pine with seven different end conditions and one change of wall condition. Changes in size and shape of discharge wore made b y short transformation pieces directly at the discharge end, with the result that effects due to contraction and expansion of the flow, which proved to be of much greater importance than was expected, totally obscured any normal effects cue to size anti shape. The results of this series of tests, therefore, relate to 10-inch pipe with various discharge designs is and ago se reported.]

Jan 1, 1940

By Efrem R. Reeves

Noise-induced hearing loss (NIHL) is the most common occupational illness in the United States, with 30 million workers exposed to excessive noise levels [NIOSH 1996] every day. Of particular concern is the mining industry; which has the highest prevalence of hazardous noise exposure of any major industry sector [Tak et al. 2009] and is second only to the railroad industry in prevalence of work-ers reporting hearing difficulty [Tak and Calvert 2008]. This document is for operators, safety personnel, and mechanics in the mining industry who are not specialists in noise control engineering or acoustics. Evaluations of successful and unsuccessful attempts at controlling noise on several large, underground metal mining machines are detailed to illustrate the basic principles of noise control. Once personnel understand the guidelines and principles of noise control, they will be able to ¦evaluate the extent of a noise problem; ¦determine the best approach to the problem; and ¦apply the most appropriate solution. Because of the insidious nature of NIHL, it can go unnoticed until a considerable loss of hearing has occurred. In some cases, diagnosis is delayed because an exposed individual claims to have become accustomed to the noise. In reality, that person may have already suffered irreversible hearing loss. Humans can hear sounds in the frequency range from about 20 to 20,000 Hertz (Hz). Within this range, NIHL usually begins in the frequency region around 4,000?6,000 Hz, the upper levels of the speech region. The first noticeable symp-toms include difficulty understanding higher pitched voices, such as the voices of females and children, and difficulty understanding certain consonant sounds, which are primarily high frequency in nature. The extent of NIHL varies depending on the level and duration of noise exposure and on an individual?s susceptibility; despite having similar noise exposure, individuals can experience differing degrees of hearing loss, or none at all. NIHL is almost always preventable. To reduce or eliminate the possibility of NIHL, an individual?s noise environment must be analyzed and appropriate action taken to reduce noise exposure.

Dec 1, 2009

By Fred N. Kissell

In This Chapter [Measuring the gas emission from the coal Methane at the top of the silo Methane at the load-out area and Actions taken after a silo explosion] Methane accumulations in coal silos have resulted in the occasional silo explosion. These can be quite violent and dangerous because coal dust adds to the strength of the blast. However, with the appropriate precautionary measures, methane accumulations in silos can be greatly reduced. Mine Safety and Health Administration (MSHA) regulations at 30 CFR2 77.201 require that the methane content in the air of any coal silo be maintained below 1.0 vol %.3 Also, MSHA requires that methane tests be conducted before any electrical equipment is energized, unless a continuous monitor capable of deenergizing the electrical equipment is used.4 Measuring the gas emission from the coal. The first necessary step in dealing with silo methane issues is to measure the gas emission from the coal going into the silo. Such measure-ments allow one to estimate the silo ventilation needs and permit a comparison with the methane controls used at other mines that have similar gas levels. The gassiness of the coal can be measured by taking conveyor belt grab samples.5 Matta et al. [1978] measured the gas emission from conveyor belt grab samples using a simple desorption test. To conduct the test, they collected several grab samples of coal, weighing a few pounds each, from the conveyor belt entering the silo.6 They then sealed the coal into an airtight sample container that was equipped with a valve and short hose along with a pressure gauge. Every few hours they opened the valve and bled the emitted gas into a water-filled graduated cylinder that had been inverted and placed in a pan of water (Figure 11–1). The results are shown in Figure 11–2.

Jan 6, 2006

By David Garry, Michael J. Brnich, Lynn L. Rethi, Henry P. Cole, William J. Wiehagen, Roberta A. Calhoun

This document contains most of the materials needed to use the exercise. The main part of the document is the instructor's copy. It tells how to use the exercise, presents the objectives, the master answer sheet, the scoring key, and discussion notes to be used following the exercise. The next section summarizes results from field tests of the exercise, and reports the miners' evaluation of the activity. The last part of this document is three appendices. Appendix A is the exercise problem booklet. This booklet can be duplicated locally. The booklets are reusable. One is needed for every person in the classroom. Appendix B is the answer sheet and the trainee's questionnaire. Copies of this answer sheet must have the latent image (invisible) ink answers that appear in Appendix C printed on them.1 Answer sheets are consumable. One is needed for each person or each small group of persons who work the exercise. Exercise Summary Read this section first. It determines if the exercise is appropriate for your classes. If you choose to use the exercise, examine the table of contents and review the remainder of this document. Type: Latent image Audience: Supervisors, Safety Personnel and Accident Investigators Length: Eight questions (30 minutes for administration plus 30 for discussion) Skills: Developing a strategy or plan to prevent slips and falls Following correct procedures in conducting an accident investigation Preventing unsafe work practices Recognizing and instituting hazard controls in the section Identifying and implementing safe work procedures Location: Underground coal mine section Problem: You have been the general mine foreman at White Rock Mine for 4 years and have worked at this mine for 12 years. The mine superintendent calls you into his office. He gives you an accident report of an employee in 4-G section who was injured while carrying rock dust bags from the rock dust car to a battery powered scoop. It is several days after the accident and the mine superintendent assigns you and the safety supervisor to thoroughly investigate the accident to determine all the contributing factors. Your job is to make specific recommendations to prevent future slipping/tripping accidents.

Jan 10, 1999