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By Michael J. Bertoldi

The purpose of this Bureau of Mines report is to describe the methods and establish the basic economics for dragline, shovel-truck, and scraper mining systems. An overall view of the techniques of preliminary design and the cost involved is presented. Considerations of equipment selection, emphasizing short-range evaluation of required equipment, and a long-range evaluation are considered at a constant production rate over the life of a hypothetical mine. Separate cost analyses for each system were based on 1977 equipment prices, prevailing wage rates, and associated mining costs. Specific engineering and cost breakdown for such items as access roads, transmission line installation, rail spurs, etc., are beyond the scope of this report.

Jan 1, 1977

By F. J. Prokoski

The COALSTAR Project, which operated from November 1981 to December 1982, was a research and development project aimed at providing a reliable and inexpensive means of monitoring various waste site conditions via the GOES satellite system. The GOES system provides data transfer from unattended isolated sites where neither power nor telephone lines exist. The reliability and resolution of the data received while using the satellite link were excellent; however, the site instrumentation gave considerable trouble. The disastrous failure of a large coal waste embankment in 1972 led the Bureau of Mines to undertake a comprehensive program to reduce the likelihood of such an occurence again. Part of this program involved the installation of instruments to monitor the stability of a specially-selected embankment operated by Armco Incorporated near Montcoal, West Virginia. Initially, the instruments were monitored by normal telephone lines and used normal commercial power from the local utility. The project described here was initiated to replace this monitoring system with an unmanned, solar-powered data collection system which transmitted data via satellite to a central computer facility. The satellite data network is the National Earth Satellite Service of the National Oceanic and Atmospheric Administration.

Jan 1, 1984

By R. Newman

An inexpensive slow-speed data acquisition system has been adapted to digitally record multiple parameters simultaneously at intervals of 15 seconds. The system was built for use with standard soils testing equipment to automatically record load and displacement parameters at predetermined instants in time. Simultaneous readout is achieved by the use of special signal conditioner and sample-and-hold circuits which read the multiple signals simultaneously and hold them until the slow acting system can print out. Three channels of a 10-channel system have been converted and found to operate successfully during a series of direct shear tests. A unique feature of the system, which significantly reduced its cost, is the power supply units. Dummy circuits are used to maintain a constant power demand during sampling) thus eliminating the need for a costly power supply with rapid response characteristics. The entire system, having an overall accuracy of 0.25 percent, was put in operation for a cost under $2,500.

Jan 1, 1970

By D. R. Corson

The Bureau of Mines instrumented an operating stope in a deep vein mine to determine the amount of wall closure and the magnitude of loads imposed on a backfilled stope. Hydraulic pressure cells used to monitor pressures in the fill) with bolt closure points to measure vein-wall movement and the procedure for their installation) are described) and the results of the laboratory calibration analysis of the reliability of these cells are given. An attempt to monitor density and moisture changes in the backfill with a nuclear density-moisture device was only partly successful) owing to either deformation of access tubing or relative displacements of the vertical vein walls relative to the emplaced tubes. Data from the instrumentation indicate vein-wall closure in excess of 20 inches and pressures within the fill approaching 600 psi. Analysis) incorporating field data with results of laboratory tests of the compressibility of timber and tests defining the constrained moduli of the fill) points out the limited restraint to vein closure offered by timber sets. Ground movement induced by mining activity could be more effectively con-trolled by the use of densely compacted backfill.

Jan 1, 1967

By Robert G. Gibson, Joel D. Gibbons

Measurements and analyses were conducted of whole-body vibration aboard seven commercially available passenger and/or recreational vehicles: sedan; sport-utility vehicle (SUV); pickup truck; moving truck; motorcycle; all-terrain vehicle (ATV); and boat. The purpose of the testing was to measure and assess whole-body vibration exposure in a range of typical vehicle environments in order to gain understanding of typical exposure levels characteristic of activities of daily living. Vehicle models tested (and model year) were: Ford Taurus (1995); Jeep Cherokee Sport (2000); Toyota Tundra SR5 (2002); Ford F-350 (1997); Harley-Davidson Electra Glide Classic (2004); Yamaha Kodiak 400 4x4; and Steiger Craft Model 21 Montauk. All vehicles were tested with their standard factory-installed seats and were operated under a range of normal operating conditions and speeds typical of intended vehicle use. Methods The measurement, processing, analysis, and exposure assessment methods follow the guidance of generally accepted, national and international consensus standards relevant to the evaluation of whole-body vibration, including ISO 2631-1 [1] and ANSI S3.18 [2]. Seats were instrumented with low-mass triaxial accelerometers mounted in seat pads. Accelerometers used in the test are specified to have flat frequency response over the frequency range of 0.5 to 80 Hz, and all accelerometers were recently calibrated traceable to the National Institute of Standards and Technology (NIST). Seat pads were installed following guidance in the relevant standards [1, 2], with sensitive axes of the accelerometers following the standard coordinate system with respect to the seated occupant. (The x-axis represents fore-aft motion; the y-axis represents side-to-side motion; and the z-axis represents vertical motion with respect to the occupant.) Vibration data processing and analysis, including filtering, sampling, frequency-weighting, averaging, summation, and determination of basic and additional metrics followed procedures in the relevant standards [1, 2]. Digitized time series data were acquired and stored using a PC-based data acquisition system. Whole-body vibration exposure analyses were conducted via post-processing. During data processing, recorded periods of seat acceleration that were identified and verified as resulting from occupant-induced motion rather than vehicle motion were excluded prior to exposure analysis. The basic evaluation metric for whole-body vibration is the frequency-weighted root-mean-square (r.m.s.) acceleration, aw. The primary additional evaluation metric is the fourth-power

Jan 6, 2006

By Terry J. Close

A mineral resource survey of the 940-square-mile (2,434 km2) Hells Canyon study area, which includes Hells Canyon Wilderness, Snake and Rapid Wild and Scenic River's, and adjoining roadless lands in Oregon and Idaho, indicates the area is highly mineralized. Thirty-four lode deposits within the study area have resources totaling about 31 million tons (28 million t) containing copper, silver, zinc, gold, and lead; another 42 lodes, not sufficiently exposed to allow resource estimates, are believed to have mineral potential. The most important deposits are copper-, silver-, zinc-, gold-, and lead-bearing volcanogenic occurrences, followed by silver-and copper-bearing contact replacement (tactite) deposits; other lode occurrences are relatively unimportant. The most important placer deposits occur at Dry Diggins; placers along the Snake River are small and scattered. The study area has extensive deposits of limestone and sand and gravel; it has little potential for energy resources.

Jan 1, 1982

This work presents: 1.) the results obtained from measurements of temperature profiles in pillars and at working faces of three coal mines located in Colorado and New Mexico, 2) a comparison of the experimental results with theoretical predictors based on linear heat flow models, and 3) temperature profile predictions based on a two dimensional coal mine model with an inclined crack located in the roof or wall of the opening. The thermal properties of the coal and shale samples taken from the mines were used as input data for the computer model. Good agreement was found between the measured profiles and the theoretical values obtained with the one dimensional model. The two dimensional model results show that a visible crack (0.01-0.07-ft thick) in a coal roof causes a surface temperature difference from 0.2 to 1°F at the edge of the crack for rock exposed to air from 1 hr to 288 hrs and with the air to rock temperature differences from 2°-6°F. A temperature difference of 0.3 °F was found between solid and broken rock in a shale roof with a 0.03-ft thick crack inclined 45° to the horizontal after a ventilating time of 48 hrs and the air to rock temperature difference of 2.1°F.

Jan 1, 1972

By Terry R. Neumann

A mineral survey of the 23,760-acre Abert Rim Wilderness Study Area (OR-1-101) was conducted by the U.S. Bureau of Mines in 1986 at the request of the Bureau of land Management in order to evaluate its identified mineral resources. The study area is located in south-central Oregon, 26 mi north-northeast of Lakeview, OR. Federal and Lake County mining records indicate no mining claims, geothermal leases, or oil and gas leases within the study area as of January 1, 1987. No economic concentrations of minerals were found in the study area. The Wilderness Study Area is dominated by Abert Rim, a north-trending Basin and Range fault scarp that parallels the study area's western boundary. Exposed on the scarp is an approximately 2,000-ft-thick volcanic sequence consisting of Oligocene-Miocene basalts, tuffs, and tuffaceous sedimentary rocks.

Jan 1, 1987

By James Gibbs

In order to provide an initial approach to the deposits of oil shale, nahcolite, and dawsonite in the central area of the Piceance Creek Basin in northwestern Colorado, the U.S.B.M. and associated contractor personnel drilled and cased a 96-inch ID shaft to a depth of 2,371 feet. The shaft was constructed using "big hole" drilling techniques and succeeded in giving access to previously inaccessible deposits of the above minerals. This report documents the construction from its beginning in January 1977 to its completion in January 1978. Procedures used and problems encountered are discussed in derail.

Jan 1, 1978

By Peter G. Kovalchik, Lawrence W. Scott, Thomas H. Dubaniewicz, Mark A. Fuller

Mine trailing cables operated above safe thermal limits can cause premature insulation failure, increasing electrocution and fire hazards. Previous U.S. Bureau of Mines Pittsburgh Research Center research showed that, under static test conditions, electrical current levels permitted under present regulations may not limit cable temperatures to less than the 90 °C rating of reeled trailing cable. Continuing research under the National Institute for Occupational Safety and Health (NIOSH) addresses thermal characteristics of reeled trailing cable under dynamic test conditions more representative of field conditions, where operators constantly reel in and pay out cable. This research is in support of efforts by industry associations and the Mine Safety and Health Administration to establish safety guidelines for cyclically rated reeled machines. This paper describes a unique approach to measuring temperatures within reeled cable under dynamic test conditions. Fiber-optic sensors embedded within the metallic conductors measure temperatures at 1-m intervals along the entire length of cable. Temperature measurements are reported to be accurate to within 1±° C. The test setup requires access to only one end of the trailing cable, allowing researchers to freely reel in and pay out cable while temperature measurements are made, simulating field conditions. Manufacture of a fiberoptic-embedded trailing cable is described, along with initial test results that indicate the fiber-optic approach is viable.

The objective of this condensed handbook is to provide the inspector with guidance for recognizing hazards from inhalation contaminants in above ground work areas of underground and surface coal mining and processing facilities and evaluating these hazards by collecting samples or making field determinations and interpreting the analytical results. It will be carried with the inspectors during their surveys. The complete handbook should be left in their offices except for Appendix II which lists the compositions of products found in previous surveys. There are several portions of the condensed handbook which should prove most useful to the inspectors. The names and locations of these portions are listed below: Procedure for an Industrial Hygiene Survey (Page 2-1) Survey Check List (Page 2-3) Rules for Determining if Sampling is Required (Page 2-2) List of Most Frequently Encountered Contaminants (Page 2-5) List of Candidate Contaminants and their Sampling Conditions (Page 2-A) Interpretation of Results (Page 3-8) For obtaining information not available from the above mentioned portions of the handbook, the inspector is directed to the Table of Contents, and the Glossary of Terms (Appendix I).

Jan 1, 1975

By Charles J. Cohen, Donald F. Reed

"INTRODUCTION AND ACKNOWLEDGMENTSThis report supplements a previous report on work done in this same area 4/ but covers only the period from November 1945 to November 1946. The project was established in 1943 to investigate magnetite deposits in the northwestern Adirondacks by geophysical surveying and diamond-drilling for the purpose of increasing iron production in the eastern United States.In its program of investigation of mineral deposits, the primary objective of the Bureau of Mines is the more effective utilization of our mineral resources, that they may make the greatest possible contribution to our national security and economy. The policy of the Bureau is to publish the facts developed by each project as soon as possible after its conclusion. Maps showing the detailed magnetic surveys of the deposits and anomalies discussed in this report are on open file at the offices of the Bureau of Mines, College Park, Md., and at the University of the State of New York in the office of the Director of the State Science Service, Educational Building, Albany, N. Y.The Mining Branch, Lowell B. Moon, chief, conducts preliminary exami¬nations, performs the actual investigations, and prepares the final report. The Metallurgical Branch, Oliver C. Ralston, chief, analyzes samples and performs beneficiation tests.The chemical analyses included in this report were made at the Eastern Experiment Station of the Bureau of Mines at College Park, Md., under, the general supervision of J. B. Zadra, chief, College Park Division, Metallurgical Branch, and the immediate direction of Dr. Alton Gabriel, in charge of the laboratory service unit."

Nov 1, 1947

This sheet explains your audiogram (hearing test) and gives some basic information about protecting your hearing. Keep it so you can refer to it later. What is an audiogram? • An audiogram is often called a “hearing test,” but there’s no pass or fail • It is a written record of your hearing levels • A series of audiograms can track changes in hearing over time • Your hearing threshold levels (the quietest sounds you can hear) are measured in decibels (dB) at different frequencies from low (500 Hz) to high (8000 Hz) Why should I get audiograms? • To measure your hearing ability • To identify hearing problems • To monitor success at maintaining your hearing • To see if noise exposure is affecting your hearing Do I have normal hearing? Compare your hearing threshold levels to this scale: -10 – 25dB Normal hearing 26 – 40 dB Mild loss 41 – 55 dB Moderate loss 56 – 70 dB Moderate/severe loss 71 – 90 dB Severe loss 91 – 100dB Profound loss [ ]

Jan 1, 2008

The selective placement of coal stripmine overburden is examined. Physical and chemical properties of spoil detrimental to revegetation and groundwater are detailed. The United States is divided into regions or similar problems. Five mining methods already used in the industry, that are capable of selectively handling waste are examined in detail. Technical and economic comparisons are made for the systems when applied to realistic mine settings. The same analysis is conducted for five novel methods capable of selectively handling waste. Comparisons are made between novel and existing methods. Suggestions for new and modified equipment are outlined. Recommendations for further research are provided. This volume contains all Appendices to the report.

Jan 1, 1981

By Lucia Kuizon

The Pinnacles Wilderness Contiguous Wilderness Study Area (WSA) (CA-040-303) is 30 miles south of Hollister, CA, in San Benito and Monterey Counties. It is composed of five parcels of public land totaling 5,838 acres adjacent to the Pinnacles National Monument. The U.S. Bureau of Land Management later reduced the size of the Recommended Suitable Area (RSA) to 2,200 acres. U.S: Bureau of Mines personnel examined the entire WSA in May 1984. The WSA is underlain by Tertiary sedimentary and Cretaceous plutonic rocks. Diatoms occur in interbedded tuff, shale, and sandstones in the northern part of the WSA, but outside the RSA. In 1984, there were no mines, prospects, mining claims, leases, or mineral resources in or within one mile of the study area. No energy minerals were identified; however, an oil well was drilled in 1951 in the northern part of the WSA, but outside the RSA; it was a dry hole.

Jan 1, 1985

By Donald O. Capstick

A mineral survey of a 5,700-acre portion of the 11,510-acre Upper Deep Creek Wilderness Study Area (ID-111-44B) in southwestern Idaho was conducted by the U.S. Bureau of Mines in 1985. No mining claims have been located, no minerals have been produced, and no resources have been identified in the study area. Three reconnaissance samples of alluvium from the Deep Creek drainage contained $0.21, $0.22, and $2.72 per cubic yard in placer gold, higher than usual for the Owyhee River canyonland area. The samples of near-surface material contained very fine gold in values too low to support large-volume commercial placer operations, but the quantity and size of the particles of gold in the alluvium is expected to increase near bedrock. Consequently, the area may be a target for recreational as well as small commercial suction dredge operations. The physical characteristics of the individual pieces of gold (bright and angular) indicate that it may have recently come from an unidentified nearby source.

Jan 1, 1986

By G. P. Houston

This is the final, report submitted for the Contract No. H0220002 with the U. S. Bureau of Mines for the design and development of a Permissible Automatic Data Acquisition System (PADAS) to measure and record roof stresses in underground mines Basically the PADAS is a portable, battery powered, 24-channel data acquisition system designed for safe unattended operation of up to 30 days duration in explosive environments. The unit will accommodate twenty-four pressure transducers or eight borehole deformation gages (or any combination) at distances up to 300 feet from the PADAS to measure pressures up to 10, 000 psig. All 24 channels as a selected group are scanned sequentially at one of several selectable rates.

Jan 1, 1973

By D. T. Randall

Several years ago investigations were begun by the United States Government to determine the most efficient methods of utilizing the coals of the United States. These investigations, which were continued along several different lines, are now being carried on by the Bureau of Mines, in accordance with the provisions of the act creating this bureau . . It was because of the need for more complete information concerning the conditions under which coal could be economically burned in boiler furnaces without objectionable smoke that tests were made at the Government fuel-testing plants at St. Louis, Mo., and Norfolk, Va. In addition to this experimental work a number of commercial plants in the larger cities were inspected to ascertain what were the best methods then in use for abating smoke. The results of these investigations were reported in Bulletins 334 and 373 of the United States Geological Survey. Because of the continued demand for the information contained in these bulletins, the original editions of which are exhausted, they are reprinted by the Bureau of Mines. The text of this bulletin, particularly the information relating to smoke ordinances, was revised in the latter part of 1910 and the early part of 1911 by S. B. Flagg, engineer, who has charge of the steaming tests being conducted by this bureau.

Jan 1, 1912

By authority of the Federal Coal-Mine Inspection Act of May 7, 1941, Public Law 49--77th Congress, H.R. 2082,2/ a Coal-Mine Inspection Division was established in the Health and Safety Branch of the Bureau of Mines. Funds totaling $729,000 for the operation of the division and for other incidental expenses were provided in an amendment to the Department of the Interior appropriation bill for the fiscal year 1942 (H.R. 4590). A small. percentage of these funds was made available on July 1, 1941, and a much greater proportion on October 1, 1941, to defray the expenses of the coal-mine inspection work and incidental activities for the remainder of the fiscal year 1942. The Coal-Mine Inspection Division is charged with administering the act and is required to compile, analyze, publish, and otherwise make available for public inspection the information obtained under it and to transmit such information to the Director of the Census. The act requires also that the information obtained be reported to Congress, with such findings and comments thereon and such recommendations for legislative action as may be deemed proper.

Jan 1, 1943

By Eric Nordhausen

This report and associated deliverables is the culmination of a comprehensive literature survey, data collection and identification of over 500 metal/nonmetal active mines/mills/smelters (over 50,000 tons per year, TPY, production) in the contiguous 48 states. The main purpose was to compile an inventory of the mine/ mill/smelter waste tonnages, thus forming a data base for future research and development in improving waste management and waste disposal techniques in the metal/nonmetal mining industry. The study specifically excluded sand and gravel, sulfur, granite and any commodity that leaves basically no waste when mined and/or milled. The coal waste inventory is the subject of another report. The study provided for locating, mapping. encodating and digitizing all the mine/mill/smelter information made available throughout the nation as well as the climatological, land use, topographical, ecological and vegetative data. Mine/mill/smelter information also included (where possible) acreage and/or volume, mining methods, primary ore and gangue minerals, waste composition and haulage methods and distance hauled. Finally, a discussion is provided concerning present and potential uses of various types of tailings, as well 8S recommending possible R&D in addressing problem areas in waste disposal techniques and management.

Jan 1, 1981