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By Loren R. Anderson

This is an Appendix of Volume I. In contains the results of the electric cone penetrometer soundings from the second phase of the testing program.

Jan 1, 1982

By Roy C. Bartholomae, Jeffrey Shawn Peterson

1. INTRODUCTION In the early 1980s, the U.S. Department of the Interior’s Bureau of Mines Pittsburgh Research Center required that a large reverberation acoustic facility be constructed. This facility was designed to determine the sound power level emissions of mining equipment, especially continuous miners and jumbo drills. A contract for a conceptual design of a reverberation chamber was awarded to Wyle Laboratories of Huntsville, AL, which had extensive experience in the design, construction, and accreditation of acoustical reverberation chambers. The following standards were referenced as guidelines for the design of the chamber: ANSI S1.31-1980, “Precision Methods for the Determination of Sound Power Levels of Broadband Noise Sources in Reverberation Rooms” and ANSI S1.32-1980: “Precision Methods for the Determination of Sound Power Levels of Discrete-Frequency and Narrowband Noise Sources in Reverberation Rooms.” Specific requested criteria included that the room be large enough to accommodate typically large mining equipment and that there be adequate acoustical modal density in the frequency range of interest. It was also required that the room dimensions would support broadband acoustical measurements down to the 100 Hz third octave band. With the closing of the Bureau of Mines in 1996, this reverberation chamber lay dormant for a number of years. However, this facility is now part of the National Institute for Occupational Safety and Health’s (NIOSH’s) Pittsburgh Research Laboratory (PRL). One of NIOSH’s missions is to decrease noise induced hearing loss among the nation’s mineworkers. To this end, PRL researchers are refurbishing and instrumenting this reverberation chamber to facilitate assessment of the various engineering controls being developed to decrease the sound power level emissions of mining equipment. Early on, this work has sought to bring the chamber up to the level of ISO 3743-21 standard for engineering grade measurements for broad-band noise, with a longer range goal of improving the lab to meet the requirements of ISO 37412standard for broadband precision grade measurements. 2. DESIGN OF THE REVERBERATION CHAMBER The nominal room dimensions are 18.3 meters long by 10.3 meters wide with a height of 6.7 meters. The chamber volume is 1,286 cubic meters. These dimensions are important, as few reverberation facilities are large enough to test typically huge mining equipment. The floor is poured concrete with a sealer to make it acoustically reflective. The walls are built of hollow concrete block, 16 inches long x 8 inches high by 12inches thick. Each block has two hollow cores. The hollow block cores were completely filled with concrete with horizontal and vertical steel reinforcing bars 16 inches on center. This was done to supply a

By Tom Tallone

In the majority of metal and nonmetal mining operations, narrow vein deposits are being mined with slusher hoists. Thin; method of mucking is costly, due in part to its inherent labor intense operation and to its inability to muck 100 pct of the deposits. Mechanized equipment would greatly improve the material handling in narrow vein mining and would dramatically reduce the operational cost. The Compact Loader/Trammer, known as the "mini-mucker" has been developed to increase productivity of the load/haul/dump portion of the typical narrow vein mining cycle. This is Volume II of the final report and concerns the operation and maintenance of the mini-mucker. Volume I covers a general and design review of the activities on the subject contract and are available under separate cover.

Jan 1, 1985

As mining operations in the United States (US) have become more productive, controlling the dust exposure of mine workers has become more challenging. In response, US mining operations are applying basic controls at elevated levels and are looking to emerging control tech­nologies in an effort to better control airborne respirable dust levels. The Pittsburgh Research Laboratory (PRL) of the National Institute for Occupational Safety and Health (NIOSH) conducts research to develop and/or improve control technologies that reduce the respirable dust exposure of workers in underground coal mines. The goals of this research involve optimizing the use of water sprays and ventilating air, as well as, evaluating emerging control tech­nologies. An overview of dust controls typically utilized in underground US coal mines will be provided. An update on ongoing PRL research efforts that are evaluating new control technologies will also be presented.

Jan 1, 2008

By J. Fletcher Smoak

The value of abrasive materials consumed in the United States increased 37% in value over that of 1983 to $439 million; of which, 58% was manufactured abrasives, 36% was industrial diamond (natural and synthetic), and 6% was natural abrasives. Production value of natural abrasives, which consist of crude tripoli, special silica stone, garnet, and emery, increased 4% Production of crude tripoli, a finely disintegrated chert, increased 12% in quantity and 8% in value. Shipments of processed tripoli increased only 3% in quantity but increased 16% in value, with large increases occurring in both major end-use categories. Production of garnet, an abundant iron-aluminum silicate, decreased slightly in quantity and value after posting continued increases in quantity and value since 1980. There was a significant decrease in the quantity and [ ]

Jan 1, 1985

Objective To develop safety training tools for mine safety and health trainers that can be used for both new-miner training and annual refresher training. Background For the past 3 years, NIOSH has been developing training materials for mine safety trainers in response to gaps identified during stakeholder meetings. Most materials have been directed to the hazards of underground mines, but the recent passage of Part 46 of CFR 30 required new-miner and annual refresher training in aggregate operations. One result was the identification of another audience needing basic information about safety in mining. Trainers characterized trainees in this segment of the industry primarily as young males, many of whom had little work experience. Approach Training specialists from the Arizona State Mine Inspector’s Office approached NIOSH researchers early in2002 about the possibility of a collaborative project to develop safety training materials for new trainees in aggregate operations. A preliminary search of MSHA accident statistics identified over a dozen common hazards that could be targeted in a training video. A storyline was developed for review by safety specialists in the aggregate industry, and a script was written to cover the selected hazards. Although the target audience was primarily new hires, the finished video was also to be relevant to more experienced workers.

Jan 1, 2003

By Thys B. Johnson

The mine system analysis and evaluation study presented in this report was part of the U. S. Bureau of Nines' Tertiary channel project conducted under the Heavy Metals program. The Badger Hill pit, located on the west end of the San Juan Ridge area, near Nevada City, California, was the site of the Bureau's field work. The objectives of this study were: (1) Determine potential alternative mining systems for some of the large tertiary channel gold-bearing gravel deposits, and (2) Identify areas of technology where further investigation would be merited because of their potential inclusion in a mining system for such deposits, The study involved the development of a mineralized block inventory, an economic block inventory, determination of optimum ultimate mining limits and a preliminary economic mining system evaluation. Computer programs were developed and utilized for each of the study phases stated above. The sampling program conducted at Badger Hill by the Bureau Delineation Group together with confidential drill hole data provided by the San Juan Gold Co. formed the basic gold values and distribution information from which a deposit model was developed. The deposit was divided into minable block units and net economic values were assigned to each block for various configurations of both open-pit and underground mining methods based on cost and performance data provided by the various Bureau of Mines Research Centers. A number of controllable variables such as: (1) Mining method (open-pit and underground), (2) depth of mining cut, (3) production rate and (4) equipment type and capacity were evaluated. The prime measures of effectiveness on which the mining systems where judged were discounted cash flow rate of return and maximum utilization of natural resources. The analysis showed that underground mining of the Six-Mile Tertiary channel gold-bearing gravel deposit under consideration was uneconomical and did not permit maximum recovery of the resources within the channel. It was also apparent that mining the Six-Mile Deposit for gold alone is uneconomical or at best marginal at a gold price less than $80 per ounce. The analysis showed that the potential for an economic mining operation within the Six-Mile Deposit exists when the gravel resources of the channel are considered together with the gold. It was determined that the highest rate of return would be realized with a 20-year open-pit mining operation yielding 745,000 ounces of -gold and 55 million cubic yards of usable gravel.

Jan 1, 2012

By Keith A. Heasley, Frank E. Chase, Christopher Mark

Deep cover retreat mining (overburden in excess of 750 ft) is an important emerging issue which will intensify in the future as the more easily mined shallow seam reserves are depleted. Analysis of Mine Safety and Health Administration (MSHA) statistics indicates that deep cover pillar recovery accounts for a disproportionate share of the underground coal mine roof/rib fall fatalities and injuries. Past research has shown that previously recommended Analysis of Retreat Mining Pillar Stability (ARMPS) stability factors (SF’s) may be excessive for deep cover pillar design. The objectives of this study were to evaluate the various methods and strategies by which panels, production pillars and barrier pillars are developed and extracted under deep cover, and to develop appropriate design guidelines. In the course of the research, 29 mines in 7 states were investigated to collect panel design case histories. At each mine site, underground geotechnical data were collected on the pillar line in order to document roof rock, coalbed and floor conditions. The analyses indicated that squeezes were the most likely failure mode where the depth was less than 1,250 ft, but bumps predominated in the deeper cover cases. Immediate roof rock quality, the ARMPS SF’s, and barrier pillar stability factors were all found to be important parameters in determining the outcomes of the case histories. Design guidelines, including suggestions for barrier pillars to isolate active panels from nearby gobs in bump prone ground, are also proposed.

By W. P. Diamond, F. Garcia, J. K. Marshall

Many longwall mines rely on methane drainage to supplement traditional fan-based ventilation systems. However, the surface production facilities for methane drainage systems, including gob gas ventholes, are commonly located in remote locations, sometimes without convenient access to electrical power, and they may be monitored infrequently. The first evidence that a methane drainage system may not be operating efficiently, or not operating at all, can be an increase in methane concentrations at a return air shaft or underground where the workforce is exposed to the risk of a methane explosion. A solar powered, remote gob gas venthole monitoring and cellular telephone-based real-time data transmission system has been developed and successfully field tested by the National Institute for Occupational Safety and Health (NIOSH) to address this problem. With this system, individual methane drainage boreholes can be monitored from the mine office to determine current operational performance parameters, as well as review past data to anticipate maintenance needs and troubleshoot operational problems.

During the initial portion of the contract several alternative designs were considered, as set out step by step in the monthly reports. The conclusions reached during this period were - to use on INTERDATA Model 70 as the system minicomputer - to drop the idea of multiplexing and digitizing the inclinometer outputs downhole due to the greater complexity and cost that that alternative would imply - to use a multitasking software monitor to enable synchronization of the several tasks that the system would have to perform simultaneously - to use a common controller for all I/0 devices except those which were available off the shelf from Interdata - to use a sheave counter to meter off equal increments of probe travel, but to supplement this information with the use of an encoder on the winch drum in order to be able to measure total probe travel unambiguously. - to place all I10 device interfaces in a bin connected to the common controller. During this period considerable attention was dedicated to the design of the mechanical components contemplated it the original contract. Of these, only those required for vertical probe was complete at the time that it was decided to forego the mechanical subsystem and concentrate on developing the necessary electronics and software to interface with the probes being developed by the Bureau of Mines.

Jan 1, 2012

By James C. Fowler

This report contains a description of the contract activities performed by ENSCO, Inc. under contract H0292025. The purpose of this project was to prove the feasibility of detecting hazards in a coal seam using a synthetic pulse radar. This work was conducted in three phases. The first was an analysis of the types of errors which might cause problems. The second was to build a breadboard radar and the third phase was to conduct a field test with the system. The work from each phase is discussed and the results of the field tests are presented. These results show propagation of the radar signal through 200 feet of coal along with reflections from 50 feet away. The final section contains recommendations for future development.

Jan 1, 1981

By Forrest T. Moyer

INJURY experience and employment data are presented in this chapter for metal and nonmetal mines, stone quarries, sand and gravel pits, iron blast-furnace slag plants, and metallurgical plants (including ore-dressing and nonferrous reduction plants and refineries) in the United States. Employment and injury experience data for all mineral industries are given in volume II. The 1962 figures are preliminary summations which are subject to revision. They were compiled from all reports from producers received by the Bureau of Mines through April 15, 1963. The data for metal, nonmetal (except well and brine operations), stone, and sand and gravel operations were collected by a mandatory reporting system under the provisions of the act of September 26, 1961, Public Law 87-300 (75 Stat. 649). The act authorized the Secretary of the Interior to study the various aspects of safety in metal and nonmetal mines (excluding coal mines) and report the findings 2 years sub-sequent to the enactment of the law. Data on nonmetal well and brine plants and nonferrous reduction plants and refineries were reported voluntarily by the operators. METAL MINES Preliminary data for the metal mining industry comprise reports on 1,871 mines and pits. The combined fatal and nonfatal injury-frequency rate was 31.95 per million manhours in 1962, a decrease of 8 percent from the similar rate of 34.54 in 1961. Metal operations reported a total of 61 fatal and 3,201 nonfatal injuries.

Jan 1, 1963

By F. S. Kendorski

This report presents the results of a search for viable-self-drilling roof bolt concepts, detailed development, design, and manufacture of such bolts that drill their own holes, and testing in the laboratory and in the field in two different coal mines of three self-drilling roof bolts. Three new types of bolts were designed and tested, which drill their own holes and then anchor in continuous operation. These were a spring-actuated mechanical expansion shell, a slot and wedge, and a self-contained resin anchor bolt. Such bolts when fully developed for mine use would allow safer and remote installation of ground support and increase productivity. Recommendations are given for further work to improve drilling and anchorage performance.

Jan 1, 1979

By E. Chin

The domination of Bangladesh's mineral industry by natural gas was in for some possibly significant changes. A modest flow of crude oil was struck in a gas development well in the northeastern corner of the country. This was the first commercial flow of crude oil in Bangladesh. All crude oil was being imported, which cost a significant proportion of the nation's foreign exchange earnings. The development of an oilfield producing only a few thousand barrels per day would be a welcome help to the economy. Additional exploration at a 1985 coal discovery in the northwest indicated a considerable reserve of good-quality coal at a depth suitable for mining. If the coal is mined, it would be a boon to the local economy because natural gas was not available in the area.

Jan 1, 1988

By Charlie Wyche

In 1980, gold, silver, and pit and quarry construction materials were the principal minerals produced in the Dominion of Fiji. The combined value of these minerals totaled some $7.2 million,2 over 85% of all mineral production, Production of cement, sand and gravel, and quarry products continued to increase, but gold and silver production from Fiji's only operating mine declined slightly from the previous year's level. Mineral exploration has been carried out by U.S., Australian, British, Canadian, West German, and South African companies since the early 1960's, and a high level of activity was maintained throughout 1980. At the end of 1980, some 40 mineral prospecting licenses covering over 4,300 square kilometers were in force, and 19 applications were under consideration by the Mineral Resources Department. Total expenditures by mining companies on land base projects exceeded $6 million in 1980.

Jan 1, 1982

By Corate L. Brierley

Low-grade porphyry copper ores containing chalcopyrite as the primary mineral was leached by two strains of acidophilic, thermophilic microbes belonging to the genus Sulfolobus. Leach tests were conducted in glass columns heated to 60-70° C. Pinto Valley and San Manuel ores sized to -1/2 inch + 50 mesh were effectively leached by the thermophilic organisms, but pinto Valley and Cyprus Bagdad ores sized to -2 inch + 1/2 inch resisted leaching. Aeration did not contribute measurably to bacterial copper extraction, since two columns, one inoculated and one sterilized, having a rest/ leach cycle without recurrent aeration exhibited copper extraction patterns similar to those of the aerated columns. Distilled water can be substituted for 9K medium without diminishing copper extraction. Decreasing the pH of the leachate to about 1.8 enhanced the extraction of copper from pinto Valley ore with the thermophilic microbes. Thiobacillus ferrooxidans was found to be relatively ineffective at copper extraction from pinto Valley ore. Of eleven solvent extraction reagents tested, Adogen 364 and Warsol at concentrations of 0.1% and 0.012 were inhibitory to oxygen uptake by the two Sulfolobus strains. Di-2-ethyhexyl phosphoric acid at concentrations of 0.1%, 0.01% and 0.001% were totally inhibitory to the respiration of both organisms.

Jan 1, 1979

By B. Gillenwater

This report describes the results of investigations into four specific areas related to trolley wire power distribution systems in coal mines. These are: 1. Partially insulated (shielded) trolley wire 2. High-speed insulator fault detectors 3. Dual-wire trolley systems 4. Insulator failure indicators. Prototype devices or designs were developed in each area. In addition, a brief survey was made in an attempt to assess the Future of mine trolley systems, and data was collected and reviewed in an attempt to analyze the nature of trolley wire related accidents. Other options for decreasing the risks associated with trolley systems that arose .during the study are briefly described in appendices. These include insulating equipment and miners from return and/or energized conductors and use of a segmented trolley wire with local control of current delivering capability.

Jan 1, 1981

By Thomas J. Peters

The U.S. Bureau of Mines and the U.S. Geological Survey are responsible for the evaluation of the mineral resources and potential of further planning areas included in the U.S. Forest Service Roadless Area Review and Evaluation (RARE II) program. The Bureau of Mines primarily evaluates mineral deposits and prospects within the areas. The Geological Survey naps the area's geology and conducts geochemical sampling. Evaluations are in conformance with the Forest and Rangeland Renewable Resources Planning Act of 1974 as amended by the National Forest Management Act of 1976. The Hauser RARE II area, which consists of 7,600 acres (3,100 ha) within the Cleveland National Forest, is in southern San Diego County, California. The area, which forms the north slope of Hauser Canyon, ranges between 1,600 and 3,919 ft (490 m) in elevation. It is sparsely to densely covered with desert shrubs. The area is underlain by granitic rocks of the Peninsular Ranges batholith.

Jan 1, 1983

By Irvin G. Burough

ANDROS INCORPORATED has designed, manufactured and delivered four handheld C02 DETECTORS and three handheld CH4 DETECTORS. These instruments are for in-mine safety use. The DETECTORS incorporated an NDIR optical/electronic analyzer design in which exceptional zero stability is achieved by pressure modulation of the sample gas. This eliminates the need for daily calibration. This stability and the miniature design (2.5" x 4.5" x 4.5"; 4.5 lbs) of the C02/CH4 DETECTORS provide practical instruments suitable for routine safety inspections. This report includes the theory and design of the instruments as well as studies of gas-pressure modulation by a piezoceramic-driven Helmholtz resonator.

Jan 1, 1979

By R. A. Franks, G. F. Friel, J. C. Edwards, L. Yuan

The reversal of smoke products-of-combustion (POC) from a mine fire was determined in a mine section with the airway connectivity of an electrical Wheatstone bridge. Four diesel-fuel fire experiments with fire heat-release rates between 504 and 771 kW were conducted in the Safety Research Coal Mine (SRCM) located at the National Institute for Occupational Safety and Health’s (NIOSH) Pittsburgh Research Laboratory (PRL). Smoke reversal propagated upwind from the fire with significant leakage into the upwind diagonal airway and without causing a complete reversal of airflow in the diagonal airway. A control measure consisting of a brattice suspended half entry height from the entry roof was determined to abate the smoke rollback. Computational fluid dynamics (CFD) analysis of the smoke movement agreed with the measurements.