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By R. V. Ramani, R. Stefanko, G. W. Luxbacher

TEST DECK - AITIHETER SURVEY WITHOUT ALTIMETER TEUPERATURE CORRECTION DATA INPUT

Jan 1, 1977

Jul 1, 2003

By Thomas V. Falkie, R. Venkataramani

Table 15. Summary of Physical Characteristics of Coal and Shale from Channel Samples. Table

Jan 1, 1972

In 2001, a total of 2,144 coal mining operations reported employment to the Mine Safety and Health Administration (MSHA). Coal mines comprised 14.7% of all mining operations. • Bituminous mines comprised 92.0% (n=1,972) and anthracite mines 8.0% (n=172) of coal mining operations. • More than 71% of coal mines were located in three states: Kentucky (29.5%), West Virginia (21.3%), and Pennsylvania (20.6%).

Apr 1, 2003

Table 1.-Employment and injury experience at metal mines in the United States, by industry groups [ ]

Jan 1, 1967

1. In 2002, a total of 256 metal mining operations reported employment to the Mine Safety and Health Administration (MSHA). Metal mines were the smallest mining sector,1 comprising 1.8% of all mining operations. • Gold mines comprised 44.1% (n = 113) of all metal mining operations. Other types of metal mines were copper ore (n = 31; 12.1%), iron ore (n = 25; 9.8%), and lead and/or zinc ore (n = 21; 8.2%). • Nevada is the state with the largest number of metal mines (n = 53; 20.7%).

Jan 1, 2004

1. In 2001, a total of 281 metal mining operations reported employment to the Mine Safety and Health Administration (MSHA) (down from 309 metal mines in 2000). Metal mines were the smallest mining sector, 1 comprising 1.9% of all mining operations. This was the lowest percentage of all mining sectors. • The median number of operator employees per metal mine was 17.5.2 • Gold mines comprised 43.1% (n = 121) of all metal mining operations. Other types of metal mines were copper ore (n = 37, 13.2%), iron ore (n = 27, 9.6%), and lead and/or zinc ore (n = 24, 8.5%). • Nearly 20% (n = 55) of metal mines were located in Nevada.

Jul 1, 2003

By Lloyd A. Morley, Robert Stefanko

Table

Jan 1, 1974

By B. Demoulin, J. Fontaine, R. Gabillard, P. Degauque

To realize a radiowave communication along mine galleries a few kilometers long without repeater, we show that it is possible to use a coaxial cable bearing an important surface transfer impedance like a transmission line with an inductive coupling to the transmitter and the receiver. We determine the electrical and geometrical constants of the cable and the optimal frequency.

Jan 1, 1973

Despite the strange names given to its parts, the eye is not a very complicated organ. If you think of the eye simply as a detector of light, you will be able to understand the mechanics of central vision, peripheral vision and adaptation described below. These three processes of seeing are basic, not only to mining, but also to everyday activities. A number of simple experiments are described In this chapter to demonstrate different types of seeing processes. Try the experiments. They really make the point. Light rays reflecting from objects enter the eye through a lens and fall on the back surface called the retina. The retina 1s lined with millions of tiny light sensors called "rods" and "cones." These sensors, in turn, are connected to the brain by the optic nerve.

Jan 1, 1976

By David Hoadley, Kenneth R. Maser, Ashok B. Boghani, James E. Billar, D. Randolph Berry, Mackenzie Burnett, Robert H. Trent

D.2 Principal Types of Coating A Sodium Silicate Sodium silicate is a good fire retarder when freshly applied, but it loses its effectiveness if the relative humidity is at all high, thus exposure to a relative humidity exceeding 65 percent causes a serious decrease in the effectiveness after only one month. In fire, sodium silicate swells to a frothy mass (intumescence) which hardens and insulates the wood against heat. This property is destroyed by exposure to moisture. Manufacturers of many of the proprietary paints containing silicates state that their products have overcome this difficulty The reagent may be applied alone, or, better, in a mixture with lime-water and common salt, or with inert fillers such as kaolin or asbestos. B Ammonium Phosphate Strong solutions (25 to 35 percent) of monammonium phosphate or diammonium phosphate give good protection. Two or three coats of hot solution should be applied either with a large flat brush or an ordinary paint spray gun The solution should be applied as hot as possible, as this improved penetration, and it should be the aim of the operator to apply 4 lbs of reagent, i e , one gallon of 33 percent solution to every 100 square feet of surface

Jan 1, 1976

By W. Blake, J. Whyatt

Sixty years of rockbursting in the Coeur d’Alene district has taught painful lessons and led to a number of practical advances in controlling rockburst hazards. This paper summarizes those lessons, concentrating on practical measures that have been successfully adopted to reduce hazards. These lessons are explained in the context of district mining history and current understanding of rockburst phenomena. Overall, the paper provides the practicing mine engineer with an appreciation of rockburst hazards and an overview of practical measures that can be used to control these hazards in the context of Coeur d’Alene district experience.

By David Hoadley, Kenneth R. Maser, Ashok B. Boghani, James E. Billar, D. Randolph Berry, Mackenzie Burnett, Robert H. Trent

APPENDIX G TABLE IX MINE A 1 General Total Employees 3000 Maximum No, of Men Underground/Shift 800 Shifts/Day 3 Type of Ore Copper Daily Production (TPD) 25,000 Mining Method Room and Pillar Vein Dip/Thickness l0°/l5 ft Number of Levels/Max Depth 1/0 to 1800 ft 2 Haulage, Conveyances and Travelway Main Haulage Rubber Tire/10 miles belts Man-Ways - Typical Route of Travel to most Remote Sites Rubber Tired Vehicles Hoists - Capacity/Speed/Depth Depth under construction 3 Ventilation 2,500,000 cfm - 5 surface fans 4 Compressed Air N/A cfm 10" and 12" lines 5 Incendiary Storage 2 day powder 1000 gal fuel oil 6 Communications 1 complete system - all shops, dinner areas, and feeder/breaker stations 2 partial systems 7 Escapeway- Systems Man Check System Section boss log and punch cards Alarm System Mine phones with paging system Posting of Escape Route Maps No Escape Signs Every intersection, fluorescent paint Evacuation Drills 2/yr/shift Refuge Chambers - 1 cinder block - No longer required

Jan 1, 1976

By R. V. Ramani, P. M. T. White, D. Sutton

6.1 Summary This report deals with the investigation carried out to select, test, and implement a method of evaluating coal deposits and reserves. Cognizance is taken of the inherent characteristics of coal and the legislation covering aspects of health, safety, environment, and ecology applicable to the coal mining industry. Further, the method is computerized and provides information that is meaningful and readily available to other programs and sub¬systems within the concept of the Master Design Simulator. The Geology and Reserves Sub-system interface with the total system is provided by a geological data library which is structured to hold and make accessible all the data required by the system. The output from the program is accurate and useful to users with a wide variety of computer experience, knowledge, hardware and storage capacity. The sub-system is designed to function as a separate unit or an integral part of the total system and, there¬fore, an interface to or with the system has been established. The work carried out by the sub-system includes: (a) The analysis of raw geological data. This involves:

Jan 1, 1974

By R. J. Matetic, D. Elsworth

The objective of this U.S. Bureau of Mines hydrologic-subsidence investigation was to evaluate the effects of longwall mining on the local ground water regime through field monitoring and numerical modeling. Field data were obtained from multiple-position borehole extensometers (MPBX's) that were used to measure subsurface displacements. Survey monuments were installed to measure mining-induced surface deformations. Numerous drawdown and recovery tests were performed to characterize hydrologic properties of the overburden strata. Coreholes were drilled above the study area to determine lithologic and strength characteristics of the overburden strata using the rock samples collected. Electronic recorders were installed on all monitoring wells to continuously monitor ground water levels in coordination with mining of the longwall panels. A combined finite element model of the deformation of overlying strata, and it's influence on ground water flow was used to define the change in local and regional water budgets. The predicted effects of the postmining ground water system determined by the model correlated well with field data collected from the field site. Without an infiltration rate added to the model, a static decrease of 3.0 m (10 ft) in water level would occur due to mining of both longwall panels and if an infiltration rate was inputted in the model, no predicted long-term effects would occur to the ground water system.

Jan 1, 1995

By Robert F. Chaiken

A quasi-steady-burning channel model is used in this Bureau of Mines study to describe the conductive heat loss from an in situ coal combustor to the surrounding rock strata. The calculated heat losses are significantly greater than those previously estimated, but are still very acceptable from the viewpoint of energy recovery. Approximately 80% to 90% of the heat of combustion of the coal should appear as sensible heat of the gaseous exhaust, with exhaust temperatures in the range of 1,000° to 1,200° C. The effects of burning stoichiometry and channel size on the heat loss are also discussed in terms of the model. Such effects are shown to be compatible with an in situ combustion process even in thin seams. However, these results depend on gas leakage and adverse roof falls not being important factors in deter-mining the heat loss mechanism.

Jan 1, 1977

By Roy L. Wilfong

Surface area measurements were conducted on cadmium sulfide powders following thermal treatments at temperatures up to 500° C and treatment times up to 1 week. Thermal treatments at temperatures up to 300° C produced no significant changes in the surface area of the powders even after 1 week of exposure. At 500° C some decomposition of the cadmium sulfide occurred.

Jan 1, 1970

By R. F. Waters

The Bureau of Mines developed laboratory-scale processes to recover sodium phosphates and metal values from waste sludges generated by the phosphate treatment of automobile and appliance components. After treatment of the sludge with NaOH, followed by coke or hydrogen reduction and sintering, zinc and lead were recovered as fume; the sinter was separated by leaching into a metallic product, chiefly iron and nickel, and high-purity disodium or trisodium phosphate.

Jan 1, 1971

By Lloyd A. Morley, Robert Stefanko

A major difficulty encountered during the research was that nation¬al countries (almost world-wide) are in the process of revising their electrical hazard reduction standards. Their principal goal is to align their standards with the International Electrotechnical Commission (IEC) Recommendations Publication Series 79. (31-37) Additionally, CENELEC is requiring all Common Market countries to harmonize their standards. (85) However in the coal mining industry some hazard re¬duction techniques are not being accepted because some systems may not be applicable. Therefore, past literature might not directly relate a country's current feeling about explosion-proof standards. An authority in the United Kingdom (which has been a leader in hazard reduction mainly through work at the Safety in Mines Research Establishment) brought up an additional point. (15) He hopes that since revising British standards BS229 into BS4683, with the intention of corresponding with the IEC 79 series, the recent CENELEC harmoni¬zation process will also follow IEC. (8, 9, 10) The past trend in other major Common Market countries prior to CENELEC's requirement results in the authors' speculation that the standards will be pattern¬ed after the IEC Publications. (5,17,60,84,102) Several letters were sent to the East Block countries but, disa¬ppointingly, replies were dispatched only from the USSR and Poland. Recent Polish standards (1973) were received, and a very close match to the IEC Publications has been noted. (76,77) Because of their economic community, it is extremely logical to assume that the East Block stand¬ards are therefore in concurrence with the IEC. Japanese specifications also appear to be compatible with the IEC Recommendations. (42,43)

Jan 1, 1974

By Lloyd A. Morley, Robert Stefanko

In the context of the following report, an hazardous location can be described as any industrial area in/which flammable or explosive gases, vapors, and dusts can be encountered. When electrical apparatus is used in such hazardous atmospheres, the chance of a dust or gas ignition is ever present. Consequently, in an effort to reduce the ignition hazard, several protection systems have been devised. Such systems are termed electrical hazard reduction techniques. The most widely accepted and used of these, the explosion-proof enclosure, is the principal subject of this report. However, other techniques are briefly mentioned. Hazard reduction techniques used in coal mine atmospheres (which can contain methane, coal dust, and air mixtures) are classified as Group I. The explosion-proof enclosure commonly used in mines is defined by the USBM Schedule 2G as a device that can contain internal explosions of methane-air mixtures without undergoing damage or excessive distortion and without an ignition of a surrounding methane-air mixture or discharge of flame. (100) Internationally, the definition remains the same except the words "discharge of flame" are not present. (4,5,31,42,52,76,102) The latter description often refers to flame-roof enclosure construction, but the terms "flameproof: and "explosion-proof" commonly have the same connotation. These enclosures which may not be vapor tight, are distinguished by heavy-wall cast or welded construction and bolted or threaded close fitting flanges. Explosion-proof enclosure techniques have been utilized in U.S.

Jan 1, 1974