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Investigation of Acid Production, Leaching, and Transport of Dissolved Metals at an Abandoned Sulfide Tailings Impoundment: Monitoring and Physical Properties

Description: Abstract: Researchers at the U.S. Bureau of Mines conducted a long-term groundwater monitoring and site characterization program at an abandoned 10-ha, acid-producing, copper-gold tailings impoundment in north-central Washington State. The purpose was to investigate contaminant release and transport, and attenuation mechanisms in the tailings, sediments below the tailings, and gravels downgradient of the impoundment. This report summarizes the monitoring results and physical properties of the t… more
Date: 1995
Creator: Stewart, Bill M.; Williams, B. C. & Lambeth, R. H.
Item Type: Refine your search to only Report
open access

Investigation of Optimum Thrust, Cutting Speed, and Water Pressure for Tungsten Carbide and Polycrystalline Diamond Compact Roof-Bolt Drill Bits

Description: Abstract: Laboratory tests were conducted at the U.S. Bureau of Mines to determine the effects of roof-bolt drilling parameters on penetration rate in sandstone using tungsten carbide alloy (WC-Co) and polycrystalline diamond compact (PDC) drill bits. During the tests, water pressure of 552 kPa was found to be adequate for removing the cuttings from the tops of drill holes. Test results show that for both types of bits, penetration rate increased when thrust was raised from 227 to 1,588 kg. Whe… more
Date: 1995
Creator: Sundae, Laxman S.; Smelser, Thomas W. & Howie, Wayne L.
Item Type: Refine your search to only Report
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A Kinetic Model for Conventional Flotation of Coal

Description: The U.S. Bureau of Mines has developed a computer model to 'describe a flotation process. Coal data from conventional flotation has been converted to a simple, two-parameter kinetic model developed by Reuter and van Deventer (j,2 3. Each set of coal data was represented by two constants, a and a, and an average flotation rate. The success of the model was demonstrated when the calculated and experimental recoveries showed good correlation. The two-parameter model allows complex data to be defin… more
Date: 1995
Creator: Susko, Frank J. & Stanley, Don A.
Item Type: Refine your search to only Report
open access

Longwall Gate Road Stability in a Steeply Pitching Thick Coal Seam with a Weak Roof

Description: The U.S. Bureau of Mines (USBM) conducted ground pressure analysis of a wide abutment-type chain pillar in a two-entry gate road of a Western U.S. coal mine with an extremely weak immediate roof. About 15 m of fragile, low-strength mudstone lies between the seam and the lowest competent roof member. Three- and two-entry gate road designs with several pillar sizes and various secondary support systems have been employed to improve tailgate-entry stability, with varying results. This report discu… more
Date: 1995
Creator: Barron, Lance R. & DeMarco, Matthew J.
Item Type: Refine your search to only Report
open access

Numerical Modeling Analysis of Stress Transfer Modification Concepts for Deep Longwall Mines

Description: Abstract: This U. S. Bureau of Mines (USBM) report evaluates three stress-transfermodification concepts for their potential in reducing longwall gate road stresses and closures. In each of the three concepts - packwalling, gob infilling, and entry filling - support structures are constructed on the headgate side of the panel parallel with or inby the face line. When the headgate becomes the tailgate of the adjacent panel, these structures are in place to accept stresses transferred from the min… more
Date: 1995
Creator: Vandergrift, Thomas L. & Jude, Charles V.
Item Type: Refine your search to only Report
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Petrographic and Geochemical Analyses of Leach Samples from Artillery Peak, Mohave County, Arizona

Description: Abstract: The first step in determining whether Mn can be recovered by in situ leaching is to develop and test a selective lixiviant. Two column leach tests and one core leach test were conducted by the U.S. Bureau of Mines on Mn oxide ore using aqueous sulfur dioxide (SO2) as the lixiviant. The column tests showed that aqueous SO2 could selectively dissolve available Mn oxides from calcite-rich ore in a heap leach system. However, the core test showed that calcite gangue side reactions can hav… more
Date: 1995
Creator: Brink, Susan E.; Blake, Rolland & Marozas, Dianne
Item Type: Refine your search to only Report
open access

Radar Positioning System Accuracy Test

Description: Abstract: The U.S. Bureau of Mines conducted research to develop an accurate, real-time, position monitoring and warning system for the vehicles used in surface mining. The product of this research will be technology to reduce accidents and injuries associated with the operation of surface mining haulage equipment. The position monitoring system should reduce accidents related to vehicle position and also increase the efficiency of haulage operations. This research was conducted in preparation … more
Date: 1995
Creator: Utt, Walter K.
Item Type: Refine your search to only Report
open access

Rapid Separation of Heavy Rare-Earth Elements

Description: The U.S. Bureau of Mines investigated the separation of heavy rare-earth elements (REE) in an ion-exchange process. An ion-exchange column consisting of two sections, a loading section and a separation section, provides high levels of REE loading and good REE separation with an expected processing cycle of less than a month, while current ion-exchange technology requires more than 5 months. A different resin is used in each section: sulfonic resin in the loading section and iminodiacetic resin … more
Date: 1995
Creator: Moore, B. W.; Froisland, L. J. & Petersen, A. E.
Item Type: Refine your search to only Report
open access

Reactivity Studies During Drying and Relocation of Lead-Zinc-Gold Tailings: Phase 1 - Preliminary Evaluation and Laboratory Testing

Description: The U.S. Bureau of Reclamation requested U.S. Bureau of Mines (USBM) assistance in developing design data for moving lead-zinc-gold tailings from their current location without disrupting the existing chemically stable conditions. This report presents results of USBM work in determining (1) the minimum required time to air dry the tailings to approximately 20 pct moisture under various drying conditions both in the laboratory and in the field, (2) the degree of oxidation or reduction that occur… more
Date: 1995
Creator: Froisland, L. J. & Lym, P. B.
Item Type: Refine your search to only Report
open access

Reducing Respirable Dust Levels During Bag Conveying and Stacking Using Bag and Belt Cleaner Device

Description: Abstract: The U.S. Bureau of Mines has designed and tested a system called the Bag and Belt (leaner Device (B&BCD) to reduce dust levels in and around the bag conveying and stacking process. The device physically cleans either 22.7 kg (50 lb) or 45.4 kg (100 lb) paper bags by using a combination of brushes and air jets. It is completely self-contained and is kept under negative pressure by a baghouse to ensure that dust and product removed from the bags during cleaning does not flow into the wo… more
Date: 1995
Creator: Cecala, Andrew B.; Timko, Robert J. & Prokop, Alexander D.
Item Type: Refine your search to only Report
open access

The Reduction of Airborne Dust Generated by Roof Bolt Drill Bits Through the Use of Water

Description: Abstract: In the vast majority of American coal mines, roof bolt holes are drilled dry, mainly because of mine operator concern with the spent water creating adverse working conditions. Wet drilling, however, can increase drilling rates and the effective lifetime of the drill bits used. This study, carried out as part of an ongoing cooperative research program between the U.S. Bureau of Mines and the University of Missouri-Rolla, shows that the large volumes of water conventionally used in wet … more
Date: 1995
Creator: Sundae, Laxman S.; Summers, David A.; Wright, Douglas & Cantrell, Bruce K.
Item Type: Refine your search to only Report
open access

Structural Analysis of a Mechanized LHD Trench Undercut Caving System

Description: Abstract: This U. S. Bureau of Mines (USBM) report presents results of stress analyses and field observations to investigate the effects of elevated trench drifts on the structural stability of rock mass zones surrounding a production draw drift in a mine utilizing a mechanized load-haul-dump (LHD) trench undercut panel caving system. A two-dimensional boundary-element mine stress model was developed to predict the locations and extent of damaged rock mass zones surrounding draw drifts where ad… more
Date: 1995
Creator: Jude, Charles V.
Item Type: Refine your search to only Report
open access

Synthesis of Advanced Ceramic Compounds by Intercalation

Description: The U.S. Bureau of Mines investigated the synthesis of advanced ceramics (SiC+AlN, SiAlON, SiC+Al 203 , and Si 3N4 +AlN) from natural clays (kaolin, halloysite, or montmorillonite) by an intercalation and heat treatment method. This process includes the steps of refining a clay, intercalating organic chemicals into its layered structure, drying the intercalated mixture, firing the treated structure at certain temperature ranges in controlled atmospheres to form desired compounds, and grinding t… more
Date: 1995
Creator: Kwong, Kyei-Sing & Bennett, James P.
Item Type: Refine your search to only Report
open access

Teleoperation of a Compact Loader-Trammer

Description: Abstract: 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 fr… more
Date: 1995
Creator: Ruff, T. M.
Item Type: Refine your search to only Report
open access

Ten-Cycle Bench-Scale Study of Simplified Clay-Hydrogen Chloride Process for Alumina Production

Description: From abstract: This U.S. Bureau of Mines (USBM) research simplified an earlier hydrogen chloride (HCl) leachsparge process developed by the USBM to recover reduction-grade alumina from domestic kaolin clay. Improvements were made by decreasing the initial leaching acid concentration from 25 to 20 pct, decreasing the leaching time from 1 to 2 h to 15 to 30 min, eliminating the solvent extraction step for Fe removal, and eliminating the step to recover the Al content of the bleedstream circuit. A… more
Date: 1995
Creator: Shanks, D. E.
Item Type: Refine your search to only Report
open access

Timing and Duration of Subsidence Due to Longwall Mining

Description: Subsidence data gathered by the U.S. Bureau of Mines over a series of longwall panels in the Pittsburgh Coalbed were studied to obtain insight as to the role of time in the subsidence process. It was found that subsidence began essentially with undermining and was completed within 1 year. The progress of the subsidence was dependent upon location above the panel. Subsidence in the central area of the subsidence trough, where subsidence is the greatest, was about 90 pct complete by the time the … more
Date: 1995
Creator: Jeran, Paul W. & Trevits, Michael A.
Item Type: Refine your search to only Report
open access

Well-Point Containment of Impoundment Leakage

Description: Research was conducted to evaluate the effectiveness of a well-point dewatering system in conjunction with a french drain to intercept waste impoundment leakage while reducing the volume of waste water requiring treatment. A well-point dewatering system composed of 585 production wells was installed around the perimeter of a leaking impoundment that previously used only a french-drain system for leakage control. The placement of the well-point system was designed to intercept and remove the lea… more
Date: 1995
Creator: Smith, C. W.
Item Type: Refine your search to only Report
open access

Coal Reserves of the Boltsfork Quadrangle, Kentucky: A Coal Recoverability Study

Description: Abstract: "This report presents a U.S. Bureau of Mines study that incorporates coal mining factors, cola recovery factors, and economic factors into the definition of an economically recoverable coal resource. The relationship between these factors to the Energy Information Administration's estimate of U.S. coal resources--the "Demonstrated Reserve Base"--is discussed. The Boltsfork 7 1/2-minute quadrangle in eastern Kentucky was selected as the stud area. Results indicate that of the origi… more
Date: 1994
Creator: Rohrbacher, Timothy J.; Teeters, Dale D.; Sullivan, Gerald L. & Osmonson, Lee M.
Item Type: Refine your search to only Report
Location: None
open access

An Overview of Research on Self-Contained Self-Rescuer Training

Description: From Abstract: "During the next 5 years investigators examined a number of factors that have a bearing upon miners' ability to put on and use the apparatus in an emergency: the procedure being taught; availability and utilization of training models; opportunities to practice; hygiene; and on-the-job-training. This report presents an overview of that research."
Date: 1993
Creator: Vaught, Charles; Brnich, Michael J., Jr.; Wiehagen, William J.; Cole, Henry P. & Kellner, Henry J.
Item Type: Refine your search to only Report
open access

Slip-and-Fall Accidents During Equipment Maintenance in the Surface Mining Industry

Description: Report issued by the U.S. Bureau of Mines discussing mining accidents during equipment maintenance. As stated in the abstract, "this U.S. Bureau of Mines report identifies potential causes of slip-and-fall accidents occurring during surface mine equipment maintenance and describes the relative roles of direct worker behavior and machine design" (p. 1). This report includes tables, and illustrations.
Date: 1990
Creator: Albin, Thomas J. & Adams, W. P.
Item Type: Refine your search to only Report
open access

Trends in Iron Casting Compositions as Related to Ferrous Scrap Quality and Other Variables: 1981-86

Description: From Abstract: "This bulletin describes the research and presents analytical results and evaluations over 5-3/4-year period from January 1981 to September 1986. Results show that iron casting compositions are charging with respect to a few tramp elements such as arsenic, cobalt, chromium, tin, zinc over the period. The data presented in this bulletin provide a means to ascertain whether the quality ferrous scrap is affecting casting quality."
Date: 1990
Creator: Nafziger, R. H.; Hartman, A. D. & Farrell, R. F.
Item Type: Refine your search to only Report
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