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Develop a cost-effective, flexible method for extinguishing underground coal mine Fires that can be readily used in fire conditions encountered in both abandoned mines and coal outcrops. In addition to the abatement of an underground coal fire, a secondary objective was to prevent subsidence by filling the voids with a material having sufficient compressive strength to minimize subsidence. Approach The Colorado School of Mines Research Institute was awarded a research contract to determine the viability of using Foaming Mud Cement for abating underground coal mine fires and preventing subsidence. The program consisted of a laboratory and pilot scale investigation and process development. An extensive, controlled test program was conducted simulating floor, rib, roof and rubble fire conditions. Field demonstrations were conducted after the pilot scale research was completed. How It Works Traditional techniques have targeted the control of burning by eliminating the air, fuel source or heat. This has been accomplished by trenching, quenching, mothering or combinations of these three methods. These techniques were not always successful, particularly in the case of fires in abandoned mines.

Jan 1, 1991

By R. S. Conti, C. D. Litton

This U.S. Bureau of Mines (USBM) report discusses the results of research conducted in the USBM experimental mine at its Lake Lynn Laboratory to determine the alarm times of smoke and carbon monoxide(CO) sensors, and a point type heat sensor (PTHS) to slowly developing coal-conveyor belt fires. The tests were conducted at air velocities of 0.44 and 0.97 m/s. The data clearly indicate that smoke sensors provide earlier warning of fire than 10 ppm CO sensors, and that 10 ppm CO sensors provide earlier warning than PTHS. A success rate of 1.0 (indicating detection of every test fire) was obtained for both smoke and CO sensors. For the PTHS, the success rate was 0.57 at the lower air velocity, decreasing to 0 at the higher air velocity. Data are also presented showing the sequence of fire events and detection events at the two air velocities as a function of time. Results show that early detection and warning of underground mine fires will improve the probability of miners’ escape.

Jan 1, 1995

Provide reasonably priced, reliable fire protection for loading shovels. Approach An automatic fire, sensing and suppression system using both dry chemical and Halon 1301 was developed. It is more rugged than similar industrial-type fire protection systems. How It Works Temperature sensors detect heat from a fire, and trigger the system. These sensors are located inside the machinery house and under the house and shovel frame where it rotates around the crawler chassis ring gear. An alarm is sounded, and extinguishing agents are released either in the machinery house or in the ring gear area. The system can also be triggered by a manual control. If the fire Is detected in the machinery house, all power is shut down to the motor-generator sets, ventilation fan, and all electrical controls. Doors are automatically closed. After a delay to allow time for the ventilation fan to stop, Halon 1301, a gaseous fire extinguishing agent, is released inside the machinery house until it reaches a concentration of about 7 percent. This concentration is sufficient to extinguish a fire, but isn't toxic to personnel

Jan 1, 1980

By M. O. Renwick, Paul Zinner

"INTRODUCTION In September 1943, the Bureau of Mines conducted a limited program of churn drilling on the Winskell property in the Shullsburg area of Lafayette County, Wis. The work was undertaken as part of a general investigation by the Bureau of the zinc-producing area of southwestern Wisconsin at a time when special effort war being made to increase the production of metals necessary for the war program.Drilling described supplemented a previous drilling program conducted by the Vinegar Hill Zinc Co. The results of both programs encouraged subsequent investigation by the Cuba Mining Co. and eventual development of the Andrews mine.ACKNOWLEDGEMENTSIn its program of investigation of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by such project as soon as praticable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the investigative work, and prepares the final report."

Aug 1, 1947

By R. Blickensderfer

Test equipment that simulated frictional impacts between coal-cutter bits and mineral inclusions at a coal face during operation of a continuous coal mining machine was used by the Bureau of Mines in the laboratory to study the incendivity of impacts between various rocks, metals, and hard-metal alloys in an explosive mixture of air-7 pct natural gas. Quartzitic sandstone was found to be the most incendive of several rocks tested. Limestone concretions from a coal seam, known locally as "sulfur balls," sparked furiously but were not incendive. Among the metals tested, the type of steel used in commercial coal-cutter tools was the most incendive material tested. A l7-4PH stainless steel was less incendive and appears to be the most promising high-strength steel alloy, reasonably economical, for use in coal-cutter bits. Some hard-metal alloys, primarily titanium and zirconium diboride composites, were also evaluated as possible replacements for the conventional cobalt-bonded tungsten carbide used in the tip of coal-cutter bits. The metal-bonded diborides were generally less inc endive but more brittle than the conventional tungsten carbide. Carbonitride coatings on tool bits were also tested but found to have no advantage. The source of ignition during frictional impact between metal and rock was studied. Immediately after impact, a yellow flash was observed and a smear of metal near its melting point occurred on the rock. This hotspot on the rock, rather than the yellow flash or sparks or metal fragments, was observed to be the cause of the ignition.

Jan 1, 1974

By T. M. Klemetti, G. M. Molinda, D. M. Pappas

Some of the most difficult coal mine roof in the U.S. can be found in the Illinois Basin. Factors contributing to the high roof fall rate include: weak moisture-sensitive roof rock, high horizontal stress, and limited longwall mining. The depth of cover ranges from 90-1,000 ft and roof damage from horizontal stress can be severe. Moisture sensitive-roof rock is common above the Springfield-Harrisburg Herrin #5 and #6 seams in the Illinois Basin, and contributes to roof skin deterioration. The roof fall rate increases significantly in the humid summer months. The National Institute for Occupational Safety and Health (NIOSH) has shown, using lab and field studies, that highly moisture-sensitive roof rock can be directly correlated to poor roof conditions. Controlling the skin is the key to reducing rock fall injuries, and roof screening is, by far, the best remedy. Illinois Basin coal operators have been successful in reducing the number of rock fall injuries in recent years. NIOSH has documented best practices for screen installation which has resulted in safe, efficient operations. Other solutions to skin failure include: the use of denser five bolts per row patterns to reduce spans between bolts, systematic supplemental support in intersections, straps and large pans protecting operators, and air conditioning to remove moisture from the intake air.

By G. G. Morgis, J. J. Forbes

"INTRODUCTION The greatly diversified and increased uses of beryllium and its con& pounds in recent years have focused attention on the health hazards incident thereto. The Bureau of Mines has a fundamental interest in safety and the elimination or reduction of health hazards in the mineral and allied industries, and it recognizes that serious hazards are inherent in the production and use of beryllium and its compounds. This circular presents a review of the literature pertaining to such health hazards but does not describe original research by Bureau personnel. Most of the bibliography has boon either quoted in part or abstracted in an effort to present information in a comprehensive and readable form.In reviewing the literature, differences of opinions wore recognized in the writings of the respective authors, but no attempt was made to evaluate such differences. This presentation was devoted strictly to reporting without editorial comment.SUMMARYAlthough beryllium was known to industry for about 150 years, its toxicity did not present any serious problems in the United States until the advent of World War II, when the increased use of this element and its compounds brought to light several toxicologic reactions occurring primarily in the lungs and skin of workers handling it. The pulmonary effects, characterized as acute pnoumonitis and chronic pulmonary granulomatosis in beryllium workers, are far more serious than the dermatological manifestations.The addition of beryllium to the list of toxic industrial metals has boon so recent that there is still some confusion in the clinical picture. Data on magnitudes of exposure likely to be responsible for the production of disease are not yet adequate. There appears to be no relation between the severity of exposure and the development of cases some of those having had severe exposure have not developed a reaction, whereas those having a slight exposure in some instances have developed a response."

Jul 1, 1950

By William R. Sharp

This Bureau of Mines report details a technique for aiding the engineer with the long-range design of an underground mine. The method is based upon the assumption that sufficient data are available to assign numeric values to some finite number of mineralized blocks; assignment of numerical values is problem dependent. By assigning appropriate weighting schemes, the algorithm developed in this report may be used to solve the optimal end-of-life underground mine layout, design least-cost electrical layout networks and efficient material handling networks, find least risk escape routes in the event of an accident, etc. The method is based upon the assumption that sufficient cost and geologic data is available to build a detailed mineral block inventory of the mineral deposit. It is further assumed that the cost assigned to any minable unit is independent of the neighboring blocks. The basic approach relies upon concepts and ideas from the theory of networks. To make the approach user oriented, a computer program is included and discussed. The computer code is written for an orthogonal, three-dimensional set of blocks. Computational costs and experience indicate that the program could be of great benefit in evaluating large complex mineral properties from the viewpoint of predesigning an underground mine layout.

Jan 1, 1974

By John J. Mulligan

The Bureau of Mines sampled a gold-bearing schist series 50 miles east of Nome near Bluff, a dormant mining camp on the southern shore of the Seward Peninsula, Alaska. Gold is unevenly distributed through a section of a schist series that extends from the coast northward 4,500 feet. In this section the schists dip westward 20 to 38 degrees and have an outcrop width of about 1,000 feet and a normal width of about 500 feet. An intensely fractured zone within the schists averages 0.015 to 0.017 ounce of gold and 0.03 to 0.05 ounce of silver per ton for outcrop widths of 200 to almost 500 feet. The grade of the remainder of the schist series ranges downward to scant traces. Gold eroded from these schists collected in solution channels in metalimestones to form the Daniels Creek placers, which also extend from the beach southward under the sea for an unknown distance. The lode sources of the gold placers elsewhere in the southern Seward Peninsula may be similar schists that occupy a similar position in the metasedimentary series.

Jan 1, 1971

By C. W. Owings

Two problems perplex many coal-mine operators and employees. Is coal-mine dust harmful to breathe; and, if so, is it possible to keep the concentration below the danger point? The medical profession is not unanimous in its opinion of the danger of breathing bituminous-coal dust, but there appears to be ample and increasing evidence that coal-mine dust can be harmful if breathed in large enough doses for long periods. The question of controlling the dust at the point of formation is still unanswered in the minds of many in the mining industry. However, results of limited studies conducted by the Bureau of Mines in 9 bituminous-coal mines indicate that a full-shift average exposure of workers should not exceed about 20 million dust particles per cubic foot of air (m.p.p.c.f.) and that concentrations can be held within this limit without too much difficulty. Furthermore, these studies indicated that an exposure in the neighborhood of 40 m.p.p.c.f. should not be exceeded for an individual operation and that it is possible to hold within this ceiling.

Jan 1, 1957

By B. G. White

NIOSH researchers have identified a pattern of fracture zone development that suggests an explanation for fracture formation around rectangular openings in underground mines. This pattern is characterized by shearing and dilation that result in either faults or in the repeated formation and propagation of en echelon fractures from sites of tension. Two computer modeling codes, Fast Lagrangian Analysis of Continua (FLAC) and Particle Flow Code (PFC), were used to model different aspects of this pattern. Use of very small elements with FLAC enabled the identification of sites of initial tension near the skin of square-cornered rectangular openings, while PFC allowed the initiation and progressive development of fractures from these sites to be followed as the fractures evolved. Such studies can lead to a greater understanding of how roof support can be better selected and installed for specific conditions in underground mines prone to roof falls and rock bursts. These studies may also lead to modifications of corner and opening shapes that could be incorporated into mine designs to produce more stable mine openings and reduce the risks of rock falls and rock bursts.

By G. Nuñez, M. A. Pathak, A. A. Afshari, C. F. Stanley

"To help evaluate the vibration patterns of an excised lung, a method is developed to determine which parts of the surface of an excised lung are responding to acoustic excitation via the trachea. Holographic interferometry, a very' sensitive technique ·that can measure movements of a few microns, is used to detect the lung surface movements.The intact lung and heart are excised from Long· Evans male rats weighing 250 gm. A tube is inserted into the trachea and connected via a funnel to a 3 inch cone speaker. The assembly is positioned in the holographic unit and excited at frequencies up to 10,000 Hz. The holographic unit contains an acousto-optic shutter used with a 0.5 watt Argon laser.The resulting reconstructed holograms contain interference fringes that are indicated of lung surface vibration.INTRODUCTIONA 1986 report by the U.S. National Committee on Biomechanics [1] describes diseases of the lung as a major national health problem. One of the recommendations of the report is for continued study of the mechanical properties of lung tissue. As an example, the report cites at least three areas that would benefit from a better understanding of the vibratory patterns or the lung."

Jan 1, 1989

By D. Hurrington

For severlrl 1e1.rs the Bureau of Mines has studied dust and ventili in metal mines a.s a.tfeoting the hea.l th, safety, and efficiency of underground workers. From its beginning this work haa been directed by G, s. Rice, chief mining engineer, A. cooperative agreement was ma.de in 1915 with the u. s. Publi Health Service; since that time tield obmervations 1n metal mines in Arizona, California, Idaho, Montana, Michigan and Nevada, and less extensive observation, in several other States have been made by mining engineers of the U, s. Bureau of Mines, and doctors of the u. s. Pu.blic Heal.th Service. Most of the analyt:J:eal work has been done by chemists, petrographers, and other specialists in the Pittsburgb station ot the Bureau of Mines, Numerous articles have been printed by the otticial and the technical press on this important in•estigation; 1n response to the need for a btiet bibliography of this literature. it has been compiled to facilitate accp1,intance with published data ot1. the subject,

Jul 1, 1922

By Maria I. De Rosa

Table 19 and figure 7 show the number of fires and fire injuries for surface coal mines by state during 1990-1999. Table 19 also shows by state the risk rates, employees' working hours, lost workdays, and coal production. For surface coal mines, 215 fires occurred in 21 states during 1990-1999. Ninety-four of those fires caused 93 injuries and I fatality (the yearly average was 21.5 fires and 9.3 fire injuries). Fourteen fires and seven injuries involved contractors. The Ewhr value was 729 x 10° hr (In = 0.026), the CP value was 6,355 x 10° st (Fn = 0.034), and the LWD value was 8,141. Kentucky had the most fires and fire injuries (45 fires and 23 injuries), followed by Pennsylvania (33 fires and 14 injuries), West Virginia (25 fires and 14 injuries), and Indiana (20 fires and 8 injuries). Among these states, Pennsylvania had the highest fire risk rate value (Frr=0.145), while Kentucky had the highest injury risk rate value (In 0.041).

Jan 1, 2004

By E. C. Lane

"INTRODUCTION This is the fourth in a series of reports on properties of commercial motor fuels, made in accordance with a cooperative agreement between the Cooperative Fuel Research (C.F.R.) Committee and the Bureau of Mines of the Department of the Interior. The first report gave data on motor gasolines sold during the winter of 1935-36 3/. The second resort gave the same data for motor gasolines sold during the summer of 1936 4/. The third report of the series gave the same data for motor gasolines sold during the winter of 1936-37 5/.This report covers 63 brands of gasoline represented by 1,136 samples excluding the Pacific Coast. Those from the Pacific Coast were averaged by the Pacific Coast technical group before being submitted and are published exactly as they were submitted. In some areas reports were received from five or six companies on the same brands of gasoline, whereas in other areas only one company reported on a brand. Thus, it can be seen that some of the data are more representative than others."

Dec 1, 1937

By Otto Robert Stein

Erodibility of reclaimed surface mine soils is a subject in need of quantification. Effects of soil erosion from reclaimed areas may damage surrounding areas and the quality of water in nearby streams and lakes. It may also reduce the potential productivity of the reclaimed site. A study was conducted to determine erodibilities of different reclamation treatments and a nearby unmined soil at three Indiana strip mine sites. A rainfall simulator was used to artifically erode plots con¬structed within seven treatment categories and the unmined soil. Soil erodibility was assessed in terms of the Universal Soil Loss Equation (USLE) K factor. Values for K calculated from field data were compared to values predicted from independently measured soil properties. Differences in soil erodibility between treatments were site specific. Unmined soil had the highest calculated erodibility at one site but at two other sites soils having reclaimed A horizons were highest. Shaley overburden treatments had the lowest calculated erodi¬bility. Predicted soil erodibility was usually lower than that calcu¬lated from field data. Site specific slope gradient factors (S) were developed for reclaimed A horizon treabnents. This was done because the USLE S factor overestimated the measured soil loss at steeper slopes.

Jan 1, 1983

By J. B. Janus

This Bureau of Mines publication updates a series of reports on the quality of coal purchased under specifications for Government use. Listed are analytical data on the composition and quality of tipple and delivered samples of coal collected during the period July 1975 through September 1976.

Jan 1, 1977

By Alan R. Buehler

The Bureau of Mines conducted a mineral investigation of the 32,270-hectare Cache Peak study area in 1992; the area had been proposed as wilderness. Bureau personnel examined and sampled prospect workings; 50 rock and placer samples were taken during the investigation. The study area is centered about 25 km southeast of Challis, Idaho, in the Challis National Forest. According to May, 1993, Bureau of Land Management mining claim records there were no current mining claims located inside the study area. Up to 100 claims may have been located in the study area in the past. Gold, silver, copper, lead, zinc: Significant analyses, poor exposure precludes resource estimate. Limestone: More than I billion tonnes may be chemically suitable for a variety of uses, markets too distant to favor mining. Dolomite: More than 1 billion tonnes may be chemically suitable for producing magnesium metal, markets too distant to favor mining. Sand and Gravel: Several million m3, but markets and transportation costs do not favor mining. Chalcedonic nodules: Two localities in the study area may be of interest to hobbyists who cut and polish stone. There is no reported past production from the study area.

Jan 1, 1993

By R. N. Roby

"INTRODUCTION A preliminary examination of the Green Monster and Benich copper prospects was made by engineers E. W. Newnan and George N. Bennett, of the Bureau of Mines, on December 13, 1943. In an unpublished report, it was stated that certain geologic features appeared to be similar to those associated with the copper deposits of the nearby Butte district. On these premises, a preliminary diamond-drilling program was recommended to explore 300 to 400 feet below the mineralized outcrops for the possible presence of a sulfide enrichment zone. In accordance with that recommendation, three holes were drilled. This report presents the data provided by that preliminary drilling exploration.ACKNOWLEDGMENTSIn its program of exploration of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell D. Moon, chief, conducts preliminary exminations, perform the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G. Knickerbocker, chief, analyses samples and performs beneficiation tests.The field work on the Bull Run exploration project was supervised byE. W. Newman engineer in charge of the Helena field office. The chemical analyses and assays included in this report were performed under the direction of A. C. Rice, acting engineer in charge, Bureau of Minos Rare and Precious Metals Experiment Station at Reno, Nev. The diamond-drill cores were logged by geologists of the Federal Geological Survey."

Mar 1, 1947

By Leonard J. Prosser, Joseph Cervik, John H. Perry

The Bureau of Mines has developed several techniques for draining methane from coalbeds in advance of mining. Drilling long horizontal holes from an underground location is one such technique, which was successfully demonstrated in the Pittsburgh and Sunnyside Coalbeds. The same technique has now been applied in the Mary Lee Coalbed at Jim Walter Resources, Inc. 's No. 4 Mine, Brookwood, Ala. , where two holes were drilled horizontally--one to a depth of 1,010 feet (308 m) and the other to 540 feet (165 m). The 1,010-foot (3083) hole proved successful in degasifying a portion of the Mary Lee Coalbed. The hole drained methane for 1 year, during which time the initial gas flow of 200,000 ft3/d (5,663 m3/d) declined to 65,000 ft3/d (1,840 m3/d). Total gas production was 40 x lo6 ft3 (1.1 x lo6 m3 ). The gas was of commercial quality, with 98 pct methane and a heat rating of 990 Btu/ft (36.89 Mj/m3). The methane emissions from the faces of the mine section advancing into the degasified zone were reduced by 60 pct. The 540-foot (165-m) hole was terminated prematurely when it became impossible to maintain an open hole. Because of caving, very little gas was drained through this hole.

Jan 1, 1982