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Enhance coal mine worker safety and productivity by developing a means to control and predict coal mine mountain bumps. Approach The Bureau of Mines has been engaged in extensive research to understand coal mine mountain bumps and their effect on underground coal mining in the United States. Information was collected on the geologic conditions, mining techniques, and engineering parameters at five mountain-bump-prone mines. Although research has not yet evolved to the point where mountain bumps can be effectively predicted or controlled, such studies are invaluable for providing clues that can lead to the development of mountain bump mitigation technology. Case Study Results and Recommendations Mountain bumps in coal mines are explosions of the coalbed that violently release the strain energy stored within it into openings created by mining. Such an event is not only dangerous to mine workers, but can cause substantial amounts of damage to mine equipment, resulting in productivity loss and downtime. In a coal mine, the occurrence may cause coal to be expelled violently from the coal face or coal pillars or cause the mine floor to heave suddenly. Coal bumps are usually accompanied by a very loud noise and tremors or vibrations. Such ground failure:; usually occur in the vicinity of an active gob line in an active retreating room-and-pillar panel, or at or near the face in an advancing or retreating longwall mining panel.

Jan 1, 1989

By O. T. Barrett, R. F. Aberethy, H. N. Cooper, Thomas Fraer, William L. Crentz

"INTRODUCTION The object of the techniques described in this report is to determine the possibilities of separating the components of a raw coal into such grades as may be necessary to recover some exceptionally clean functions for special purposes.To do this commercial gravity methods would require separation at very low specific gravities, entirely outside the range of conventional practice. Hence, a technique has been developed for breaking down cool ample, into very close fractions within the gravity range of the (-lean coal matter as well as for separating it from the refuse and particles.Such data on the fundamental specific-gravity consist of the clean-coal matter will serve to appraise the difficulty of the problem and to chow be accomplished if and when effective methods of making such separations commercially are developed."

May 1, 1945

By W. H. Tomlinson

During the 9 years ended December 31, 1938, 188 fatalities resulted from preventable accidents in and around the coal mines of Indiana; 173 of these occurred at underground mines and 15 at stripping or open-cut operations. In addition, there may have been other unrecorded fatalities during this period. The two organizations receiving notice of accidental deaths at coal mines in this State are the Division of Mines and Mining and the Indiana Industrial Commission. Only deaths occurring at underground mines employing 10 or more men are reported to the former, as neither strip mines nor underground mines employing fewer than 10 men cone within the purview of the Indiana mining law. The mine inspectors have no Jurisdiction over this latter group of mines and do not inspect them. Fatalities at small "wagon" mines and open-cut operations are supposed to be reported to the Industrial Commission; however, in many instances deaths at small mines are not reported, the only record being a death certificate filed with the county or corporation health officer. Thus, many deaths in small mines escape attention, especially when the victim succumbs some time after the injury was received. The data presented here on fatalities in Indiana, during the past 5 years include several instances in which the only record available is a death certificate; possibly others have been overlooked. From 1934 to 1937 the fatality record was progressively worse, that of the larger underground mines in 1937 being more than twice the average for these mines for the previous 4 years and only slightly less than twice the average for all mines, including open-cut operations. The increase in deaths during 1937 was due to two explosions, with 20 fatalities in one and 2 in the other. The number of deaths in the larger underground mines was considerably less in 1938 than in the previous 4 years, but there was no improvement in the number of fatalities at the small mines, or at open-cut mines.

Jan 1, 1940

By R. Luhrman, E. Christ, B. Gores, S. Fischer, E. Johanning

North American railroad locomotive operators (engineers and conductors) are exposed to multi-axis vibration and shocks (1, 2). A recent epidemiological survey showed a prevalence of serious type of neck and lower back disorders nearly double that of a control group (3). Ergonomic working conditions are important co-factors in a vibration and shock exposure risk assessment (4, 5). The goal of this study is to illustrate typical work stations (cabs and seats) in US/Canadian type locomotives and assess shock related exposure risk by calculations of the new proposed shock risk indicators according to the new ISO 2631-5 (2004) (6). Methods Locomotive cab and seat inspections were conducted and operators’ activities were assessed by a trained observer. Field measurements (n=50) were obtained during normal revue service following generally accepted guidelines (ISO 2631 (1)). A sub-sample of n=20 locomotives were selected for the calculation of proposed shock indicators (ISO 2631 (5)). Results There has been little change in basic locomotive cab and seat design in the U.S.. Two locomotive cab design concepts are used: the Association of American Railroad (AAR) Control Stand and in newer series wide-body locomotives the “Control Consol” (Figures 1-2), with varying seating conditions, but frequently subjecting the operator to an awkward body posture in addition to the vibration and shock exposure. [ ]

Jan 6, 2006

By C. H. Riggs

This petroleum-engineering report of the Atlanta oil field in BO them Arkansas reviews reservoir conditions and pressure-production history of one of the important Smackover limestone fields in southern Arkansas. The study of the field was made and the report prepared to aid operators in this and similar fields to increase the efficiency of recovery through the application of better engineering practices. A similar study of the Magnolia field in Arkansas by Carpenter and Schroeder was the first of these reports prepared under a joint agreement between the Arkansas Oil and Can Commission and the Bureau of Mines. The increasing demands for petroleum and its products and the steadily increasing cost of discovering and developing oil field; emphasize the importance of conserving known reserves of oil and gas. In recent years vast improvements have been made in the technique of oil recovery, both by better utilization of the natural energy stored in the reservoir and by improved methods of applying external energy to the reservoir system. This report may aid in oil conservation by careful evaluation of the several factors that did or did not contribute the greater recovery in the Atlanta field and by suggesting improvements in production methods and applications.

Jan 1, 1949

By Peter L. Swanson

NIOSH has developed an automated PC-based seismic monitoring system for use in mine ground control studies. The distribution and coordination of data acquisition and processing functions across a local area network (LAN) is a central feature of the system. Design requirements include (1) the use of lowcost, off-the-shelf, data acquisition and computer hardware, (2) the capability of automatically merging waveform data sets from different types of monitoring systems, (3) delivery of raw and processed data underground and on the surface, as well as to remote sites, and (4) automated data collection and processing over long periods of time without the need for human intervention. Current mine-wide installations utilize multiple, autonomous seismic networks located both underground and on the surface and provide 20 to 40 stations within a radius of several kilometers. Event locations, magnitude estimates, and other processed data are distributed for display and analysis on network nodes both underground and in the offices of mine engineers and managers. This paper describes the system's hardware and software components, examples of installations in hard-rock and coal mines, and a few observations from western U.S. longwall coal mines.

By L. C. IlsLey, R. A. Kearns

"The electrical section of the Bureau of Mines has obtained copies of all available State safety rules and regulations in order to make a study of those portions of the codes relating to electrical equipment. While it has been found almost impossible to compare the several codes as a whole, comparison of those regulations dealing with a single subject has proved both interesting and instructive.Sixteen states have rules or enactments having reference to telephones and the present paper covers a compilation of these references. It is believed that data of this kind will be of service to commissions or other bodies contemplating the revision of existing codes.The compilation taken from the various codes follows: State Rules and Regulations.California.Sec. 5 (Par. c) Telephone communication shall be maintained between a co-operative station and each mine which it supplies. If the foreman in charge of a station does not reside thereat, his residence also shall be in telephone communication with each mine supplied by his station.Sec. 8 (Par. a) Whenever a fatal accident occurs in or about any mine, notice thereof shall be given promptly by telephone or telegraph if possible, followed by a notice in writing to the chief inspector, by the superintendent or other person having immediate charge of the work at the time of the accident."

Jun 1, 1921

A revolutionary development in blasting materials has occurred in the past 5 years. Ammonium nitrate, sensitized by the addition of a few percent of No. (class) 2 diesel fuel or other suitable petroleum product, has been adopted as a low-cost, efficient blasting agent2/ by a wide variety of mining and heavy construction operations. Moreover, ready availability of the component supplies throughout the Nation and ease of their formulation into effective blasting agents have made it possible for the blaster himself to pre-pare the mixes at the site of use. Although these field-mixed products have partly or wholly displaced explosives such as dynamites in some applications, there are other blasting operations where the fuel-sensitized ammonium nitrate agents do not appear to be well adapted. Important safety characteristics are inherent in ammonium nitrate-based blasting agents prepared under competent factory control, or when field mixed under equivalent close control--as long as the hazards they present are clearly understood and respected. This publication attempts to summarize knowledge of those hazards and to incorporate practical ways to cope with them. A series of safety recommendations thus is presented. These recommendations cover the preparation, storage, transportation, and use of field-mixed ammonium nitrate blasting agents.

Jan 1, 1960

By Amanda Azman, Richard Hi Danie/son

Ultimately, the most important product of a hearing conservation program is the prevention of hearing loss, not the amount of hearing protection that has been purchased or whether employees are attending their annual training sessions. Audiometric testing directly reveals whether hearing losses are actually occurring in a plant. With audiometric data, we can assess overall program effectiveness, alert workers of impending hearing loss, and reveal potential employer liabilities for compensable hearing loss. Without the ability to efficiently analyze audiometric data or produce effective reports, our programs become fruitless and unproductive. Consequently, ifaudiometric data are such vital end-products, then effective audiometric technologies serve as the prime architect and generator of these fundamental data. These technologies, consisting ofaudiometers, associated peripheral hardware, and database/reporting software, deserve our consideration.

Improve the efficiency of stainless steel pickling (chemically cleaning) operations by providing the industry a quick and convenient method to estimate pickling solution behavior and to estimate recommended ranges of nitric and hydrofluoric acid concentrations for effective pickling of stainless steels. Background Iron, chromium, and nickel in stainless steels react with nitric and hydrofluoric acids during pickling. Ions of these dissolved metals complex or combine with the acid anions. When the total metal concentration reaches about, 50 grams per liter of pickling solution, the solution no longer serves its purpose and is considered spent. Knowledge of cation and anion species in these pickling solutions contributes an insight into pickling chemistry and allows estimates to be made of the most effective ranges of acid concentrations. The Bureau developed a computational model of the complex equilibrium chemistry occurring among iron, chromium, and nickel and the pickling solution. Total concentrations, in grams per liter, of nitrate, fluoride, iron, chromium, and nickel were used as input; output was 17 cation and anion molar concentrations. The model, in the form (if an equilibrium program on a mainframe computer, was used extensively to facilitate Bureau research by determining chemical complexes in numerous stainless steel pickling solutions. However, the program's availability to members of the stainless steel industry, its intended users, was limited because of lack of mainframe compatibility and the difficulty of program maintenance.

Jan 1, 1989

By R. Sainath, Wils L. Cooley

Continuous monitoring of ground bed resistance is essential to insure a low-resistance path for fault currents, lightning strokes, and electrostatic discharges. This paper explains the salient features of the continuous ground bed monitor and its applications. The importance of a low-resistance path to ground is highlighted. Sample readings obtained with the ground bed monitor are included, and typical applications of this instrument are illustrated. This effort was supported by the U.S. Department of Interior's Bureau of Mines under USBM grant G0144138.

Jan 1, 1979

By M. K. Larson, B. G. White

Researchers at the National Institute for Occupational Safety and Health (NIOSH) are investigating the causes and mechanisms of roof failure in underground mines. It is expected that a better understanding of these causes and mechanisms will lead to better layout and support designs that will help prevent accidents and fatalities associated with fall of ground. Two numerical experiments were conducted by NIOSH researchers using the Fast Lagrangian Analysis of Continua (FLAC) computer modeling program with a strain-softening continuum to simulate fracture zones. Two models, one of a round hole in a plate and one of a rectangular opening, were constructed and boundary conditions were applied to simulate far-field shear. The Particle Flow Code in Two Dimensions (PFC2D) computer program was used to look at the effects of far-field shear in generating fractures around an underground opening, but these models are preliminary until boundary conditions, strengths, and stiffnesses are matched to the FLAC models. Results showed that shear zones propagated from the opposite corners of openings in directions that appeared to be determined by opening shape and far-field stress. Tensile failures also formed and extended away from these shear zones. The consistent direction of shear deformation with respect to far-field shear provides a plausible explanation for preferred directions of shear as seen in geologic environments.

By R. J. Fantel

To determine the availability of phosphate rock from domestic re- sources, the Bureau of Mines evaluated the potential production of phosphate rock from the demonstrated resources of 130 mines and deposits. The evaluation included an estimation of resources, engineering methods, and capital and operating costs, and an economic analysis to determine each operation's average total cost of production over the life of the mine, including a 15-pct discounted-cash-flow rate of return on all investments. Quantified but not evaluated in this report are substantial phosphate resources at the inferred and hypothetical resource levels. The 130 mines and deposits contain 6.4 billion tons of recoverable phosphate rock product, about 20 pct from producing mines. At total production costs of under $30 per ton in January 1981 dollars, about 1.3 billion tons of phosphate rock product is potentially available, over 90 pct from producing mines. This study suggests that production from low- cost, high-grade phosphate mines now in operation will decline during the next decade, and new higher cost, Lower grade mines will have to be developed to satisfy demand into the next century, In addition to the demonstrated resources evaluated in this study, 7 billion tons of inferred-level and 24 billion tans of hypothetical- level phosphate rock are potentially recoverable, which, in part, includes material containing high amounts of magnesium, Much of this material could likely become available in the near future.

Jan 1, 1983

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 F. A. Penning

A number of highly instrumented free fall tests were performed on an arrestment system for a man cage in a vertical shaft. Tests were conducted in the U.S. Bureau of Mines free fall test tower at the Colorado School of Mines. A single tooth safety dog was used to stop on 4x6-in. Keruing (Phillipine mahogany) wet and dry wood guides. The safety dog had a penetration depth of 1 in., an adjustable width from 1-1/2 to 2-1/4 in., and a tooth angle of 80 deg. Twenty-seven free fall tests were performed covering a range in weights from 3-1/2 to 10-1/2 tons, hoisting velocities from 850 to 1350 feet per minute. Average g loads were measured from a low of 0.6 to a high of 3.4. The electronic instrumentation included piezoelectric and seismic mass accelerometers, strain gages on structural and mechanical elements, load cells in the guides, and distance measuring. Computer analysis was used to correlate with experimental measurements used to calculate stress. A statistical analysis gave no indication that the velocity or area affected the wood crushing stress. The instrumentation revealed a chatter occurring during the stop as shown by the accelerometers, strain gages, and load cells. Additional work is required to analyze this newly discovered phenomenon. The chatter imposes loads much higher than the average g load.

Jan 1, 1980

By Gerald T. Homce, Michael R. Yenchek, H. Kenneth Sacks, James C. Cawley

Abstract—Overhead electric power lines present a serious electrocution hazard to personnel in a variety of industries. Overhead lines, typically uninsulated conductors supported on towers or poles, are the most common means of electric power transmission and distribution, and are exposed to contact by mobile equipment such as cranes and trucks. Equipment contacting energized overhead lines becomes elevated to a high voltage, and simultaneous contact by personnel of the “hot” frame and ground can cause serious electrical shock and burns. Industries where risk of these accidents is greatest include construction, mining, agriculture, and communications/public utilities. An estimated 2300 accidental overhead line contacts occur each year in the U.S. This paper describes a practical low-cost concept to detect actual contact of mobile equipment with a high-voltage line and provide a warning. Accident statistics indicate that more than half of the fatalities could be prevented by such a device. Index Terms—Crane, electrical shock prevention, engineering control, mining, mobile equipment, power line.

By Paul T. Allsman

Iron-ore deposits in southwestern Utah, as the major source of iron ore for western steel plants, were investigated by the Bureau of Mines in 1942-45 in cooperation with property owners and operators and with the assistance of the United States Geological Survey with a view to determining and extending the known reserves. The factual data resulting from that project were presented in a previous report and in a report on the geophysical surveys now in course of publication. The present report has been prepared in response to expressed public interest in the ore reserves of Iron County. Mining began in the district in 1871} but. did not become important until 41 1923. From 1923 to 1946, inclusive) production totaled 10,139,500 long tons. In 1945 the district yielded 1,931,749 long tons containing 52.84 percent iron; in 1946 the corresponding figures were 1,317,671 and 53.75. The deposits lie .in a narrow, 23-mile long belt extending northeasterly from Washington 'County into Iron County along a line of mountains, chief of which are Iron Mountain, Granite Mountain, 'and Three Peaks in Iron. County. The deposits are hematite-magnetite bodies, chiefly in limestone near its contact with the monzonite of the mountain masses, but with a few important veinlike bodies in the monzonite or at the contact. They range in size from small pods to several millions of tons, and in depth from surface or near-surface to a known maximum of 1,300 feet:

Jan 1, 1948

By H. V. Makar

A study was conducted by the Bureau of Mines to determine problems associated with the use of ferrous fractions from urban refuse as melting stock for steelmaking and to evaluate the resulting steel products. The study involved 50-pound ingots from laboratory melts and 50-pound ingots from 1-ton electric-arc-furnace melts. The 50 pound ingots from the laboratory melts and the arc-furnace melts were hot rolled to provide material for mechanical and corrosion testing. Results obtained in the study include the following: Most steels rolled successfully and exhibited acceptable surface and edge condition. Tensile strengths of the plain carbon steels were not significantly affected by copper up to concentrations of 0.65 pct and were not affected by tin content up to 0.16 pct. Yield strength increased with increasing copper and tin contents, and impact strength decreased with increasing tin content. Hardness increased slightly with increasing copper content. In general, properties of the steel produced were not measurably affected by charge composition (that is, melting stock), melting practice, or method of scrap preparation.

Jan 1, 1975

By Martyn F. Roetter

The work of the operational communication systems' group dealt with a range of communication needs and functions within mines, primarily along haulageways, to and within sections up to the working face itself, and in mine shafts. A mixture of communication techniques and hardware is needed to satisfy this variety of communication needs within the differing environments encountered in U.S. mines. Substantial progress, both experimental and theoretical, has been made in recent years towards developing alternative communication systems suitable for use in mines which are based on "guided" waves, including wire-less (waveguide-like propagation in mine tunnels) and wire-based systems (leaky coaxial cables or wires) . Major priorities identified for further work needed to confirm (or deny) the applicability, and refine the operational specifications of promising communication systems for mine use include: Short-Term Projects o Cost/performance analyses of promising leaky coaxial cable and UHF radio communication systems which require further data from: - Experimental investigation under U.S. mine conditions of the performance of potentially applicable leaky coaxial cable communication systems developed in Europe (France, Belgium, and the U.K). - Cost estimates on these coaxial cable communication systems. - Measurements of UHF radio propagation in low-coal mines. - Investigation of the influence of obstacles (e.g. shuttle cars and section machinery) in the entries on UHF radio propagation in mines. o Investigation of the problems of transmitter and receiver coupling and termination matching associated with the two-way propagation of low frequency radio waves in hoist shafts.

Jan 1, 1973

By Franxis Church Lincoln

"INTRODUCTION During September 1944, the Bureau of Mines undertook a program of investigation and limited exploratory drilling at the Last Chance mine, near the village of Arthur in Grant County, Wisconsin, as part of a general investigation of the zinc-producing area of southwestern Wisconsin when every effort was being made to increase the production of metals important to the Nation's war program.The Bureau's attention was directed, to the Last Chance mine when the operators discovered high percentages of zinc in an exploratory churn drill hole a short distance southeast of the mine. The ore was found in the Trenton Limestone, which underlies the ore horizon then being mined. To determine whether this discovery was important, and to demonstrate the possible extension of the ore the Bureau of Mines drilled five additional holes in the vicinity of the discovery.ACKNOWLEDGMENTSIn its program of exploration of mineral deposits, the Bureau of Nines 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 B. Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report."

Mar 1, 1947