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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 Eric Zahl, John Dunford, Hamid Maleki

Coal bumps are defined as sudden failures of rock and coal near entries that are of such a magnitude that they expel large amounts of material into a mine opening. Coal bumps are influenced by geologic conditions, the geometric design of coal mine excavations, and the sequence and rate of extraction. Researchers from private industry and the National Institute for Occupational Safety and Health have studied mechanisms of violent failure and have identified individual factors that contribute to coal bumps. In an attempt to develop tools for assessing coal bump potential, the authors initiated a comprehensive study using information from 25 case studies undertaken in U.S. mines. Multiple linear regression and numerical modeling analyses were used to identify the most significant variables contributing to coal bumps (excluding bumps related to fault-slip). Twenty-five geological, geometrical, and geomechanical variables were considered initially. The most important of these variables were then identified as (1) energy as calculated using the mechanical properties of the strata, depth of overburden, and joint density, (2) mining method, (3) pillar factor of safety, and (4) stress gradient and yield characteristics.

By John Durkin

Owing to the daily exposures of uranium mining personnel to 222Rn daughters, a device is needed that will continually monitor individual exposure. Such a device has been built and tested by the Bureau of Mines and is known as a radon daughter dosimeter. This is an electronic instrument using a solid-state detector and circuitry. The concept of the instrument, which is a personal device worn throughout the working shift, is to evaluate an individual's cumulative exposure to airborne radon progeny, expressed in units of working level hours. Since the instrument is in close proximity to the miner and measures continual exposure, it avoids the errors caused by the present technique of spot checking of the environment and provides a more accurate account of total cumulative exposure.

Jan 1, 1977

By J. J. Drost

The feasibility of basic oxygen furnace (BOF) offgas heat recuperation by preheating scrap was investigated on a pilot plant scale by the Bureau of Mines. In this study, offgases generated during the oxygen blowing of a molten pig iron and scrap charge were passed through a static bed of shredded auto scrap. Scrap quantities varying from 100 to 180 pounds and representing from 22 to 40 percent of the 450-pound BOF metallic charge were preheated in this manner. Average scrap bed temperatures of 1,650° F for 100 pounds of scrap and 1,150° F for 180 pounds of scrap have been achieved during the blows. As compared to cold scrap used in the normal BOF practice, it was found that by preheating scrap, usage could be increased by 43 percent. The thermal energy recovered by this preheating method can account for up to 44 percent of the energy necessary to melt the scrap.

Jan 1, 1974

By K. K. Kershner

To meet an increasing demand for high-purity cobalt, the Bureau of Mines has conducted investigations for producing this metal. Cobalt having a purity of 99.95 percent or higher is needed to determine heats of formation, corrosion resistances, phase diagrams, and other basic properties of the element and its compounds. This grade of cobalt may be used for preparing radioactive metal. As a result of its investigations a detailed procedure, which is of practical significance to the production of high-purity cobalt, has been developed by the Bureau for purifying cobalt solutions and for electrolytic deposition of the metal. Cobalt metal, which had a purity of 99.99 percent with reference to metallic contaminations, was deposited electrolytically. Qualitative spectrographic analysis showed only traces of calcium, copper, iron, magnesium, nickel, and zinc.

Jan 1, 1956

By Walter R. Storms

This paper , which describes the mining methods and costs at the Atwood copper mine in the Lordsburg ( Virginia ) Mining District of Hidalgo County , N. Mex . , is one of a series being prepared by the Mining Division of the Bureau of Mines on mining practices , methods , and costs in various mining districts of the United States . The mine and surface plant are situated in the west half of sec . 7 , T. 23 S. , R. 18 W. , about 3 miles by road southwest of the center of Lordsburg , near the old abandoned townsite of Valedon ( see fig . 1 ) . The main line of the Southern Pacific Railroad passes through Lordsburg , as does the paved eastwest U. S. Highway 70-80 . A spur line of the Southern Pacific ends near the mine . A good graded road connects the mine with Lordsburg . The following pages present a brief history of the district , describe the geology , and outline methods of prospecting and exploration, including sampling and estimations of tonnages and values . Development, and mining methods are explained , and transportation , ventilation , drainage ,. safety measures , and organization are described . The wage scale and costs of development and mining comprise the corrcluding sections of this circular .

May 1, 1949

By R. D. Leitch

"INTRODUCTION This report is another of the series on the effect of drouth and low water on the pollution of streams by coalmine drainage. A previous report3 dealt with work on Bennett Branch of Sinnanahoning Creek, Pa. This report deals with the results obtained during a similar study of Black Lick Creek, Two Lick Creek, and Yellow Creek. All of these belong to the same drainage system. Two Lick Creek is a tributary to Black Lick Creek, and in turn Yellow Creek is a tributary to Two Lick Creek, as shown in Figure 1.Black Lick Creek was of such a volume that a seasonal investigation was not entirely feasible. Yellow Creek was found to have mines only near the mouth, except a few of status unknown to the writer at the extreme head-waters, and the stream was also more or less inaccessible for regular and frequent sampling. Two Lick Creek was found to be most suitable of the three.ACKNOWLEDGMENTThe work reported has been carried on under the direction and with the advice of Dr. R. R. Sayers, chief, health and safety branch, and W. P. Yant, supervising engineer, Pittsburgh Experiment Station."

Jul 1, 1931

In the U.S. coal mining industry, a large cohort of miners is at or nearing retirement age. As these miners retire, there will be a need to hire and train thousands of new and most likely younger workers. Moreover, a large portion of safety trainers will also require replacement due to retirement. In a speech before the U.S. House of Representatives (2004), Bruce Watzman, Vice President for Safety, Health and Human Resources for the National Mining Association said, “[W]e will need to replace a major portion, approximately 50%, of the underground coal mining workforce within the next 5–7 years.” The large influx of new mine workers, along with the deficit in safety trainers, creates the challenge to provide consistent and effective safety training. Given the expected high turnover of the mining workforce, it is very likely that incoming workers will have much less experience than those leaving the workforce. Unfortunately, inexperienced miners have been shown to incur the highest rate of injuries. The piece of machinery most associated with these injuries is the roof bolting machine, which accounts for 56% of machinery-related injuries in underground coal mining. The National Institute for Occupational Safety and Health (NIOSH) has released a new report entitled “Roof Bolting Machine Operators Skills Training for a Walk-Thru Roof Bolter: Trainer’s Guide” (IC 9489). It is designed to help safety trainers develop struc-tured training for new operators of walk-thru bolting machines. This resource will help trainees learn, understand, and apply knowledge and skills. Included in the trainer’s guide are the following tools: [ ] a six-part DVD video series, a skills check survey, talking points, and a complete job training analysis. Also included is an exercise to help trainees learn more about their mine’s roof control plan, as well as a list of supplemental training and reading materials. On-site trainers can modify this guide to fit their particular mine conditions, machines and equipment, and work procedures. The goal of every coal mine safety professional is to increase safety awareness and make mines a safer place to work. The Walk-Thru Bolting Machine Trainer’s Guide will help teach new miners skills to create a safer working environment that will ultimately prevent or reduce on-the-job injuries. Safety trainers can also use the ideas and concepts from this guide to develop their own training skills for the safe operation of other pieces of underground coal mining equipment.

Jan 6, 2007

By J. L. Stauffer, S. L. Lacey, L. J. Gaydos, L. M. Demers, D. C. Kuhn

"Tumor necrosis factor alpha (TNFa) and thromboxane A2 (TXA2) are major products of the activated alveolar macrophage and serve as key mediators of lung injury. In order to determine if the synthesis ofTXA2 and the release ofTNFa are associated, the production of these inflammatory agents by the human alveolar macrophage (AM), as a result of activation by lipopolysaccharide (LPS), was assessed in the absence and presence of the thromboxane synthase inhibitors UK 38,485 (Dazmegrel) and OKY 046. UK 38,485 and OKY 046 inhibited both LPS-stimulated TXA2 production and TNFa release in a dose-dependent manner. Prostaglandin E2 (PGE2) production was not increased by UK 38,485 or OKY 046. Neither LPS nor UK 38,485 had any effect on LT84 production by AM. Neither UK 38,485 or OKY 046 had any effect on LPS-stimulated interleukin-I beta release. However, the TXA2 mimetic, U46619, did not stimulate TNFa release by AM either in the absence or presence of UK 38,485. These findings suggest that 1) UK 38,485 and OKY 046 are inhibitors of both TXA2 production and TNFa release by activated human AM, 2) UK 38,485 probably does not exert its inhibitory action on TNFa release through effects on eicosanoid production and 3) the possibility that TNFa- and TXA2-induced lung injury may be subject to amelioration by imidazole-based compounds should be further evaluated.IntroductionTumor necrosis factor alpha (TNFa), produced by monocytes and macrophages, is a potent peptide mediator of lung injury (1,2). The exaggerated release of TNFa has been implicated in the etiology of acute lung reactions such as septic shock of bacterial or viral origin (3,4). The role of TNFa is expressed primarily through its ability to activate a variety of cell types within the lung environment including polymorphonuclear leukocytes (PMNs, ref. 5), type II epithelial cells (6) and fibroblasts (7). The role of lipid mediators in lung disease has also been extensively characterized (1). In particular, the relationship between pulmonary inflammation and fibrosis and the production of oxygenated derivatives of arachidonic acid (here termed ""eicosanoids"") appears to be a key factor in a variety of disease processes in the lung (8). The alveolar macrophage (AM) synthesizes primarily prostaglandin E2 (PGE2). thromboxane A2 (TXA2) and leukotriene 84 (LT84, ref. 9). These eicosanoids have been shown to produce a variety of effects in the lung including bronchial smooth muscle dilatation (PGE2, ref. 10), vascular smooth muscle contraction and platelet aggregation (TXA2, ref. 11) and oedema and immune cell extravasation (LT84, ref. 12)."

Nov 1, 1995

By E. P. Youngman

This paper is one of a series of digests of foreign mining legislation and court decisions that is being prepared in advance of a general report relative to the right of American citizens to explore for minerals and to own and operate-mines in various foreign countries. This interpretation of the mining laws of Greece was prepared from information furnished by Ralph B. Curren, American assistant commercial attache, Athens, in reply to a questionnaire of the United States Bureau of Mines, transmitted through the courtesy of the commercial laws division of the Bureau of Foreign and Domestic Commerce. INTRODUCTION In his report,3 Mr. Curren states that the source of his information was the Director of Mines of the Greek Ministry of National Economy and the Mining Code of Greece, which was, compiled from existing laws in 1929,4 and which has since been modified by several acts of Parliament.

Jan 1, 1932

By Joseph N. Harstead

This Bureau of Mines report provides information on the first 49 water-flood projects (or units) in Nebraska. All injection was in the ?D? or "J" Cretaceous sands of western Nebraska. Specific data presented include location, map, discovery and development, water supply and injection, oil and water production, estimates of oil in place, primary and secondary recoveries. The 49 projects studied) including four dual-zone projects, should recover about 126.5 million barrels of oil. Eighty-six percent of the estimated oil had been recovered by the end of 1966. Abundant water was found near most projects.

Jan 1, 1967

By T. M. Ruff

The U.S. Bureau of Mines has developed a portable, inexpensive teleoperation system for mobile hard-rock mining equipment. The system was tested on a compact loader-trammer in a simulated stope. The teleoperation system includes radio remote control and computer-assisted navigation. A recent enhancement includes video cameras mounted on the machine to provide visual information to the operator. This system allows the operator to remain in a safe location while operating the machine from a distance, thus increasing both operator safety and mining productivity.

Jan 1, 2010

By R. L. Anderson

Mechanical cleaning of bituminous coal in the United States was begun about 1875, with plants in western Pennsylvania and Illinois. The United States Geological Survey began to record the quantity of washed bituminous coal in 1906; and the series was carried forward to 1923, except that no data were collected, for 1922. This statistical work was transferred to the Bureau of Mines in 1925, and the collection of data on mechanical cleaning was resumed in 1927. Data collected before 1927 include only the coal that was washed at the mines and do not include that cleaned by pneumatic methods at the mines and that cleaned at central washeries operated by consumers.2/ The total bituminous coal washed in 1906 was less than 10 million net tons. In 1927, the first year for which complete figures are available for all types of mechanical cleaning, 28 million net tons of bituminous coal were cleaned in the United States.

Jan 1, 1951

By Ivan F. Avery

PRODUCTION of carbon black decreased 4 percent in 1961. Output in the major producing States of Texas and Louisiana decreased 1 percent and 8 percent, respectively. Production of channel black continued downward, declining 10 percent in 1961 compared with 9 percent in 1960. Furnace black production also decreased 3 percent from 1960. Total domestic sales, however, increased 2 percent, Sales to most major consumers increased, but sales to the ink industry decreased 10 percent. Producer's stocks decreased 5,083,000 pounds during the year. Exports decreased 4 percent. SCOPE OF REPORT Carbon black is a very pure grade of quasi-graphitic carbon; particle diameters range from 50 to 5,000 angstrom units. Annual reports were submitted to the Bureau of Mines by operators of all commercial plants in the United States.

Jan 1, 1962

By Homer J. Ballinger

The Mary Arnold Mining Co. in 194.3 owned 292 acre s of mineral land in Christian County, Mo., and was one of two companies with milling facilities in southern-central Missouri. Production from this property between 19.37 and 1941 amounted to 1,718 tons of zinc in the form of zinc concentrate. Because of the urgent war requirements for additional zinc and the existing facilities for treatment of zinc-lead ores at these mines, in the winter of 1943-44, the Bureau of Mines investigated the deposits by churn drilling in an endeavor to outline enough ore to maintain production of zinc from this district. Five holes aggregating 1,043 feet were bored.

Jan 1, 1948

By T. M. Garland

A nomographical approach is proposed as a fast, easy-to-use, and reason- ably accurate method for estimating expected discounted cash flow (DCF) rate of return and payout time for onshore development drilling and oil production. All costs pertaining to drilling, completing, and equipping development wells, annual expenses of operation, maintenance, and taxes incurred in producing properties, and crude oil prices were considered in developing the nomographs. This report briefly outlines the origin, derivation, and use of the nomographs.

Jan 1, 1973

By J. S. Malesky

"INTRODUCTION The Airdox method of breaking coal utilizes compressed air under high pressure and was developed to replace explosives. It is used in Illinois and Indiana mines to a large extent and also has been introduced in mines in a few other States.ACKNOWLEDGMENTThe author gratefully acknowledges the information and photographs furnished by the Cardox Corp.HISTORYIn the early 1920's, with the adoption of mechanical mining in States where on-shift shooting was prohibited, it became desirable to develop some means of breaking coal from the face without the use of explosives. At that time it was thought that a pressure of 20,000 pounds per square inch would be necessary to break the seal. It was impossible to obtain a compressor that would develop this pressure therefore, the 'patentees developed and applied the Cardox method, which utilizes liquid carbon dioxide as the blasting medium."

Aug 1, 1948

By Allen D. Look, J. Howard Bird

"INTRODUCTION The Phelps-Dodge Corp. New Cornelia Branch open-pit copper mine operated without a fatality in the drilling and blasting department from December 13, 1937, to April 1, 1947, and continuing.Between the dates named the explosives crews had a total of 746,520 man-hours of exposure and handled 12,000 tons of explosives, over 770,000 detonators, 2,300,000 feet of fuse, and 7,700,000 feet of Primacord in loading holes to break 116,780,000 tons of material.It is the purpose of this paper to record the procautions taken to insure safe handling of explosives at this operation where safety is definitely a matter of forethought rather than chance.GENERAL INFORMATIONThe New Cornelia Branch open-pit mine operates on a large, low-grade, disseminated-copper deposit about one-half mile south of Ajo, Ariz. The pit is approximately oval; the ore body being some 4,800 feet long and 2,750 feet wide. Ore is mined with electric shovels loading into railroad cars. All benches in- the pit are 40 feet in height except two, which are 60 feet high.The New Cornelia ore body differs from most porphyry-copper deposits in being hard and siliceous. In common with the other low-grade porphyry-copper deposits, continued operation is possible only with economical handling of large tonnages. This has necessitated a great deal of study in the evolution of a safe and efficient method of handling the large quantities of explosives needed in breaking this hard-rock material."

Feb 1, 1948

By George H. Schnakenberg, Aleksandar D. Bugarski

This report reviews the performance and applicability of technology for the control of emissions from diesel-powered equipment used in underground coal and metal/nonmetal mines. The methods discussed include Mine Safety and Health Administration-approved low-emission engines, engine derating, fuels, fuel additives, diesel oxidation catalysts, and diesel particulate filters. The potential of each of these technologies is examined individually and in combination. The performance estimates are derived from the published literature and presented in narrative and Tabular form. The purpose of this report is to help the mining industry select the most appropriate method to reduce underground exposures of miners to diesel exhaust in the context of the recently developed diesel regulations. It is important to note that the control technologies discussed in this report have received limited evaluation in underground mines. Additional research is ongoing, and some engineering design changes may need to be implemented before all of these diesel emission control technologies can be safely and successfully used in underground mines.

Jan 1, 2002

1. Data from the Mine Safety and Health Administration (MSHA) indicate that a total of 44,015 employees worked in underground mining locations in 2003, corresponding to 44,778 full-time equivalent (FTE) workers. • Ninety percent of underground employees (n = 39,735) were mine operator employees. • Contractors comprised 10% of all underground mining employees (n = 4,280) and comprised only 5.8% of all underground FTEs. • The majority of underground employees worked for coal operators (73.0%; n = 32,130).

Feb 1, 2005