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By P. C. Van Natter

Numerous mine fires have resulted in high death tolls and considerable finan¬cial loss during the history of coal mining. In most instances the death toll and financial loss were greater because of inadequate fire-fighting facilities. The information in this report is presented in the hope it may serves as a guide in the selection, placement, and care of fire-protection systems in similar coal mines. The adequacy of fire protection varies according to size of operation, employment, and production. When fires occur on the surface or underground, measures must be applied quickly to prevent incipient fires from spreading. The record of coal-mine fires shows that, in many instances, facilities for combating fires were very meager or were absent. It would be virtually impossible to establish and maintain all the necessary facili¬ties that may be needed to extinguish widespread mine fires, but it is believed that the coal industry can ill afford less than the minimum required by other industries where the time element and avenues of escape are much more favorable.

Jan 1, 1958

By Forest J. Sur

"INTRODUCTION This report describes an exploratory project conducted by the Bureaus of Mines on a fluorite deposit, near Glenwood, N. Mex. Results of wagon drilling, crosscutting, and test pitting are given, together with results of metallurgical tests made upon samples of the ore. Mining and treatment methods are suggested.C. H. Johnson, Bureau of Mines engineer, examined the deposit in August 1942. H. E. Rothrock, of the Federal Geological Survey, completed a preliminary geologic study and mapped the deposit during the fall of 1942. As a result of these brief investigations, it was concluded that the deposit contained substantial inferred ore reserves, and exploratory work was recommended. G. A. ApelI, also of the Bureau of Mines, made a topographic and underground survey and report on the mine in March and April 1944. A wagon drill, air compressor, and other equipment and supplies were delivered to the property on May 19 to 23, 1944. Drilling began under the direction of the author on May 25, 1944, and was completed in October 1944. The results of drilling and. sampling form the basis of this report."

Apr 1, 1947

By Frank L. Hess

In 1876 cassiterite was identified in the placer gold from the northern Black Hills, and such a mixture could have come only from Nigger Hill or one of the streams draining the hill, because in no other hart of the northern hills have cassiterite anti gold been found together. Nigger Hill is in western Lawrence County, South Dakota, and on it is the little camp of Tinton. The Wyoming line runs along the west side of the hill and crosses the ridge which is the hill's continuation about miles north-northwest of Tinton.

Jan 1, 1938

By Frank L. Hess

In 1876 cassiterite was identified in the placer gold from the northern Black Hills, and such a mixture could have come only from Nigger Hill or one of the streams draining the hill, because in no other part of the northern hills have cassiterite and gold been found together. Nigger Hill is in western Lawrence County, South Dakota, and on it is the little camp of Tinton. The Wyoming line runs along the west side of the hill and crosses the ridge which is the hill's continuation about miles north-northwest of Tinton.

Jan 1, 1938

By Q. H. Forbes

"The high injury rand fatality rate in coal mining, as compared with other industries, has caused the mining industry to become more and more interested in accident prevention methods.The prevention of accidents in the mining industry is probably not as simple a problem as it is in other industries, but if the experience of coal mining companies who have taken up the work of accident prevention seriously during recent years means anything, there is little doubt that most mining companies car improve their accident records very materially.Such results can be obtained in practically all instances without adding to production costs. In fact, there is little doubt that a well-organized program of accident prevention Will bring about a 'material production cost reduction due to increased efficiency, lower labor turnover, fewer delays due to accidents, better satisfied workmen, and a direct saving in compensation costs as well as many other items of expense.The more closely a. person is connected with the work of accident prevention, the more he becomes a believer in the value of amity in human relationships and the more he is able to exercise a spirit of toleration, fairness, justness, and helpfulness toward the problems of others, whatever those problems may be. Human nature responds to just these expressions of good willAnother great and invaluable effect of working for safety, is the fact that it is building up in the mind an appreciation of that which is constructive and, conversely, in opposition to that which is destructive In other words; the person who is sincerely striving to prevent accidents because they are destructive, costly, tad injurious, is subconsciously training his mind to look on any proposition from a constructive point of view. Working for accident prevention and safety is about the finest social training any person can have. It does not make a Person a financial Wizard or an executive genius, but it does make for the highest type of citizenship.While humanitarian reasons alone should be sufficient to maze accident prevention work an important factor in every mining organization, there are other reasons as well, since it has been proved conclusively that there can be no efficiency and economy without safety, as somebody pays when safety is lacking. Every safety device pays dividends; every safety application evaded is an assessment and a loss. Dangerous conditions are the most expensive and extravagant conditions in or about a coal mine. The economic gains are of considerable interest to all coal mining companies and this is brought about as before stated--through decreased compensation rates, the reduction of labor turnover, etc."

Dec 1, 1930

By David H. Yee

Because of environmental concerns, the Bureau of Mines investigated an anhydrous chlorination process for the recovery of copper from chalcopyrite, Pelletized concentrate was reacted continuously with chlorine in a vertical shaft reactor at 550° to 750° C to extract copper-iron chlorides and elemental sulfur. The resulting molten metal chlorides drained from the reactor and collected in a receiver while sulfur distilled from the top and condensed in a separate unit. The tests were conducted in a 10-cm-diam reactor constructed of glass and in l5-cm-diam reactors constructed from various refractory materials. A high-alumina ramming mix exhibited the best resistance to molten metal chlorides and elemental sulfur in chlorine atmospheres. A reactor made with this high-alumina refractory was operated for 55 hr under actual chlorinating conditions without suffering any deterioration. Tests results show that more than 96 pct of the chalcopyrite was converted to copper-iron chlorides and elemental sulfur. Good separation of the metal chloride and sulfur products was achieved. After filtration, elemental sulfur of greater than 99 pct purity was obtained.

Jan 1, 1977

By John A. Johnson

The first report of investigations5/ in this series pertaining to the investigation of stemming at the Mount Weather testing adit dealt with dust produced from blasting. The present report discusses the effect of stemming on eases generated by blasting, describes the test procedure, and analyzes the results from, blasting 61 standard rounds. Following care the types of stemming that -,re being investigated: 1, No stemming. 2. Sand in 2 paper cartridges. 3. Clay in 2 paper cartridges. 4. Commercial hydrated lime in 2 paper cartridges. 5. Combustible blasting plugs. 6. Ceramic is blasting plugs with clay in 2 paper cartridges.

Jan 1, 1940

By J. H. Maysilles

The Bureau of Mines is conducting research on various technologies to recover alumina from domestic resources for feedstock to existing aluminum smelting capacity as a means to reduce dependence on imported bauxite, which represents 93 pct of U.S. aluminum requirements. One of the more promising technologies being investigated is the hydrochloric acid leaching of kaolinitic clay. In the hydrochloric acid leaching technology, alumina is recovered from iron-free aluminum chloride leach liquor and separated from impurity elements by sparging the liquor with HC1 gas to crystallize aluminum chloride hexahydrate (ACH). A large-scale crystallizer with a 336-gallon usable volume was constructed and operated to obtain engineering and design data for potential scale up and to demonstrate the ability of the technology to produce specification grade alumina. Test campaigns involving about 1,400 hours of operation were completed. ACH meeting all chemical purity requirements could not be produced by a single crystallization, but was produced by recrystallizing the product from the calcined kaolin clay leach liquor. Product crystals with a size distribution of more than 80 pct plus 100 mesh and 65 pct plus 65 mesh were made at a rate of 10 pounds of ACH/(hr)(ft3). The zirconium tube heat exchanger used to maintain constant process temperature operated with an over-all heat transfer coefficient of 420 to 500 BTU/(hr)(ft2)(°F).

Jan 1, 1981

By Virgil J. Stachura

The Bureau of Mines conducted a series of delayed blasting experiments at a West Virginia contour coal mine that resulted in smoother highwalls. The 17; were smoother due to reduced overbreak and inherently safer A, to reduced likelihood of rockfall. Reduced overbreak was accomplished by an increase in the highwall hole delays, which changed the effective delay pattern geometry and the direction of burden movement. The blast delays in the highwall holes were 50 to 100 ms longer than the mine's nominal design pattern (flat V, 17- by 42-ms surface delays, 200-ms in-the-hole delay). The burden movement was effectively changed from a 45* angle to 90* with respect to the highwall. The results of the blast delay changes were evaluated using terrestrial photogrammetry to generate vertical profiles at regular intervals. This evaluation showed that delay changes produced generally smoother vertical profiles.

Jan 1, 1984

By F. K. McIntosh, A. F. Robertson, T. J. Ballard

"INTRODUCTION Molybdenum deposits occur in Halifax County, N. C., near the eastern border of the Piedmont province. The deposits are associated with a small granite body about 2 miles long and half a mile wide. Molybdenite is the principal ore mineral and is found as disseminations or thin stringers in quartz veins and occasionally in the enclosing granite or schist wall rock.The deposits were investigated by Almon F. Robertson and Charles J. Cohen, engineers of the Bureau of Mines, in 1942 and 1943, who recommended that the deposits be explored to supplement reserves of critical war minerals.The Bureau made the initial exploration of the deposits in July 1943 and continued its work to January 1944. Drilling was resumed from July to December 1946 to test the deposits at &eater depth than had been attempted during the previous exploration."

Dec 1, 1947

In 2005, a total of 4,490 stone mining operations reported employment to the Mine Safety and Health Administration (MSHA). Stone mines comprised 30.6% of all mining operations. ? Mines producing the primary commodity of limestone (crushed and broken) comprised the largest number of operations (n=2,039; 45.4%). ? Stone mining operations were located in all states and territories except Delaware and North Dakota. ? Of all states, Pennsylvania had the most stone mines (n=379; 8.4%).

Jan 1, 2008

By John D. Foulkes, David A. Curtis, Robert L. Lagace, John L. Rothery

An investigation is made of the feasibility of developing compact transmit antennas and/or other means to efficiently couple VLF to MF band radio energy between portable wireless communication units in coal mines. The completely wireless communication ranges between two portable radios equipped with practically-sized reference loop antennas in representative coal mine environments are estimated. Antenna technology is assessed with respect to transmit moment, range, intrinsic safety, battery and wearability requirements to deter- mine the most suitable antenna types for use by miners. It is concluded that air-core bandolier loop antennas, and perhaps ferrite-loaded loop antennas, having peak transmit moments of about 2.5 ampere-m5 will be the most effective antenna choices for portable units. This choice, however, will not allow the range goal of 1350 feet to be attained in mines having unfavorable signal attenuation and noise environments. Rectangular air-core loops are compared with grounded horizontal-wire and vertical-wire mode exciters for fixed station applications. The potential for significantly increasing the wireless communication range by inductively coupling to communications and power lines in a mine is evaluated and found to be considerable based on theoretical coupling equations. Lastly, the theoretical performance of a hybrid noise cancelling diversity receiving technique that utilizes both the electric and magnetic field components of the ambient noise to improve the receiver output signal-to-noise ratio under certain adverse conditions is estimated and shown to be favorable when the magnetic and electric field noise components are highly correlated.

Jan 1, 1977

By John W. Adams

The present status of the National Bureau of Standards program is that many magnetic tapes of analog data have been recorded in four major mines. Each mine uses different types of equipment. In addition, some surface measurements of noise have been made at two additional mines. Two types of recordings have been made: (1) broadband measurements for spectral plots and (2) narrowband measurements for amplitude probability density (APD) plots. Only data from one mine (Robena #4) has been processed and was, presented at this workshop. The short-term goals are: (1) finish processing data from the other mines, (2) establish or reduce measurement system uncertainties, (3) put Robella report into final form for distribution, and (4) hold a review to determine what has been done, to distribute and to interpret the preliminary data, and to determine what still needs to be done. Long-term goals are: (1) complete final reports on each of the mine trips, (2) establish techniques for predicting noise in mines already visited and establish uncertainty bounds for these predictions, and (3) establish techniques for predicting noise in mines that have not been visited (but that use similar equipment to those visited) and also establish uncertainty bounds for these predictions. Specific factors or formats to be presented include: (A) For underground broadband measurements: 1. 300 Hz to 100 kHz spectral plots 2. 300 Hz to 384 kHz spectral plots 3. 300 Hz to 192 kHz spectral plots 4. 300 Hz to 6kHz (subject to change to 3 or 12 kHz) spectral plots (B) For surface broadband measurements: 1. 300 Hz to 6 kHz (or 12 kHz) spectral plots 2. 300 Hz to 3 kHz spectral plots (C) For underground narrowband measurements : 1. APD plots at 12 frequencies from 10 kHz to 32 mHz of magnetic field strength 2. R. M.S. and average values will be calculated based on time averaging for these plots (D) Sample spectral measurements of: 1. Roof-bolt voltages 2. Trolley wire-to-rail voltages 3. Phone line currents

Jan 1, 1973

By D. A. Hill

This volume contains a summary of the results of past analyses on U.S. Bureau of Mines Contract No. H0122061 which are relevant to electromagnetic location in mine rescue situations. The analytical results indicated that detection of a trapped miner equipped with a special transmitter is feasible in most situations. Location of the miner by surface measurements is also generally feasible within certain errors. The feasibility of miner detection and the accuracy of miner location have been examined theoretically for a wide variety of situations. Agreement with experimental results is generally good in cases where measurements are available.

By NIOSH Publications

In 2004, 14,478 mining operations reported employment statistics to the Mine Safety and Health Administration (MSHA). Almost half (48.9%) were sand and gravel mines, followed by stone mines (30.4%), coal mines (13.9%), nonmetal mines (5.1%), and metal mines (1.7%).

Sep 1, 2007

By A. D. Mah

To assist Bureau of Mines research in extractive metallurgy and to add to the thermodynamic data base useful to others, energy calculations were made for 63 reactions relating to investigations on the production of anhydrous aluminum chloride from chlorination of clay.

Jan 1, 1982

This manual is for use by mine operating personnel and vehicle manufacturers in the selection and proper use of automatic fire protection systems for underground metal and non-metal mining vehicles. Most of the currently available systems are manually operated, dry chemical fire suppression systems. When properly designed, installed, and maintained these systems have proven to be effective both in fire suppression and in withstanding the rugged mine environment. Portable fire extinguishers and manually actuated systems have provided adequate protection for most of the reported fire incidents. However, there have also been incidents where injuries and property losses would not have occurred if the vehicle had been protected with an automatic fire protection system. The need for reliable automatic systems exists when the operator is not present, especially when the vehicle engine is running without the operator in the cab; and also in cases where the operator leaves the vehicle to fight a small fire with a portable and is then forced to abandon the vehicle because the small fire becomes uncontrollable. In the later cases manual systems on the vehicle are never actuated. Although these incidents have been relatively few in number in the past, the increasing use of mobile diesel powered equipment and the related importance of personnel safety, high costs of the mining vehicles, and high cost of down time warrant consideration of automatic fire protection systems. The fire history data and the design concept discussed in this manual were developed under the Bureau of Mines Contract H0252038 which is part of the government's mining research safety program. The purpose of the contract was to develop a low cost, reliable, prototype automatic fire control system for underground vehicles. The industry needs were determined through an extensive mine visitation program, and the prototype system was demonstrated on a vehicle in an underground mine fire test. The system developed under this contract was specifically designed for a load-haul-dump. However, the design concept is applicable to the full general class of mobile underground mining equipment.

Jan 1, 2011

By A. J. Kraemer

[The Bureau of Minas for a number of years has been studying the properties of crude petroleum from producing fields in the United States and Western Hemisphere and has published a series of reports on these fields, including oil fields of Texas.5]

Jan 1, 1927

By J. H. Soulé

The Copper King copper-gold-silver deposit was discovered about 1880. Various individuals and companies have been interested in the deposit and considerable work has been done, although production, if any, has been small. The deposit is located in the western part of Laramie County, Wyo., and is favorably situated with respect to rail and truck transportation and high-tension power facilities. Mild summers and cold winters characterize the climate. Precipitation averages between 16 and 17 inches annually, with considerable snowfall in the winter. Permanent streams are small and most available water in being stored for use by Cheyenne, Wyo. Range grasses comprise the bulk of the vegetation, with small trees and shrubs common in the most rugged areas.

Jan 1, 1955

By John A. Johnson

The first report of investigations5/ in this series pertaining to the investigation of stemming at the Mount Weather testing adit dealt with dust produced from blasting. The present report discussed the effect of stemming on eases generated by blasting, describes the test procedure, and analyzes the results from, blasting 61 standard rounds. Following care the types of stemming that are being investigated: 1, No stemming. 2. Sand in 2 paper cartridges. Clay in 2 paper cartridges. Commercial hydrated lira in 2 paper cartridges. 5. Combustible blasting plugs. 6. Ceramic is blasting plugs with clay in 2 paper cartridges.

Jan 1, 1940