UNT Libraries Government Documents Department - 424 Matching Results

Search Results

prev Results: 25 - 48 next
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
open access

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

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
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

A Profile of Workers' Experiences and Preparedness in Responding to Underground Mine Fires

Description: The purpose of this study was to determine mine workers' state of fire-fighting preparedness and the technology being used to detect and respond to underground coal mine fires. To investigate this problem, 214 underground coal miners were interviewed by U.S. Bureau of Mines researchers. Frequency distributions of workers' responses are presented in this report, along with segments of narrative accounts, to profile miners' fire-fighting capabilities. The data indicated that much variability exis… more
Date: 1996
Creator: Vaught, Charles; Fotta, Barbara; Wiehagen, William J.; Conti, Ronald S. & Fowkes, Richard S.
Item Type: Refine your search to only Report
open access

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

Adhesion of Diamond Films on Tungsten

Description: The U.S. Bureau of Mines has investigated the chemical vapor deposition of diamond films on tungsten substrates. The effects of deposition parameters on the adhesion of the films was determined. The films were produced using a hot filament chemical vapor deposition system. Parameters investigated were substrate temperature and methane concentration in the feed gas. Film quality, morphology, and composition were characterized by scanning electron microscopy and Raman spectroscopy. Adhesion testi… more
Date: 1995
Creator: Maggs, K. J.; Walkiewicz, J. W. & Clark, A. E.
Item Type: Refine your search to only Report
open access

Electrochemical Reduction of Titanium in Nonaqueous Solvents

Description: Abstract: Electrorefining of Ti in nonaqueous solvents has been studied by the U.S. Bureau of Mines as a method for recycling impure scrap Ti. Electrochemical behavior of Ti species was investigated using cyclic voltammetry. Research results showed that Ti metal can be dissolved in polar solvents such as dimethylformamide or dimethyl sulfoxide. However, deposition of Ti from these solvents was not successful. Several solvent systems were investigated for electrodepos.tion of Ti but no deposits … more
Date: 1995
Creator: Sibrell, P. L.
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

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

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

Application of Field Measurements and Computer Modeling to Evaluate Deep Mine Shaft Stability in Northern Idaho

Description: Abstract: Researchers at the U.S. Bureau of Mines have developed personal-computer-based data acquisition, instrumentation, and mine visualization and modeling techniques to evaluate a mine accessway in a deep hard-rock mine in northern Idaho. These techniques were applied to a mine shaft in a large silver mine that has been in operation for many years. A very deep, rectangular, timber-supported shaft extending to depths exceeding 2.3 km (7,500 ft) had been deforming continuously as a result of… more
Date: 1996
Creator: Beus, Michael J.; Orr, T. J. & Whyatt, J. K.
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

Midnite Mine Summary Report

Description: The Midni'e Mine is an inactive, hard-rock uranium mine in Stevens County, WA. Oxidation of sulfide-containing minerals in the ore body produces large quantities of acidic water. The U.S. Bureau of Mines was directed by Congress in Fiscal Year 1994 to perform technological research on the treatment of radioactive water and disposal of treatment residues at the Midnite Mine and en overall site reclamation. This Report of Investigations summarizes the studies that were completed on: 1) treatment … more
Date: 1996
Creator: Dean, N. E.; Boldt, C. M. K.; Schultze, L. E.; Nilsen, D. N.; Isaacson, A. E.; Williams, B. C. et al.
Item Type: Refine your search to only Report
open access

U.S. Bureau of Mines Final Report : Midnite Mine Water Treatment Studies

Description: The U.S. Bureau of Mines reviewed and evaluated options for treatment of the approximately 500 million gallons of contaminated water in flooded pits at the Midnite Mine on the Spokane Indian Reservation. While current lime treatment produces discharge quality water, the resultant sludges are radioactive, presenting a disposal problem. Of the 24 commercial processes and seven emerging technologies evaluated, none demonstrated a significant advantage over ion exchange using a strong base anion ex… more
Date: 1996
Creator: Schultze, L. E.; Nilsen, D. N.; Isaacson, A. E. & Lahoda, E. J.
Item Type: Refine your search to only Report
open access

Hydraulic Characterization of Midnite Mine, Wellpinit, Washington: Summary of 1994 Field Season

Description: The Midnite Mine is an inactive uranium mine on the Spokane Indian Reservation in Washington State. Oxidation of sulfide-containing minerals, primarily pyrite, produces acidic water. Uranium and other radioactive constituents are chemically leached and dissolved in ground and surface waters. The U.S. Bureau of Mines (USBM) has worked closely with the Bureau of Indian Affairs, the Bureau of Land Management, and the Spokane Tribe of Indians to address data needs for remediation of the disturbed a… more
Date: 1996
Creator: Williams, Barbara C. & Riley, John A.
Item Type: Refine your search to only Report
open access

Hydrologic and Geophysical Studies at Midnite Mine, Wellpinit, Washington: Summary of 1995 Field Season

Description: Abstract: The Midnite Mine is an inactive, hard-rock uranium mine on the Spokane Indian Reservation in Washington State. Oxidation of sulfide-containing minerals, primarily pyrite, produces large quantities of acidic water. Uranium and other radioactive constituents are chemically leached and dissolved in ground and surface waters. The U.S. Bureau of Mines (USBM) has worked closely with the Bureau of Indian Affairs, the Bureau of Land Management, and the Spokane Tribe of Indians to address data… more
Date: 1996
Creator: Williams, Barbara C.
Item Type: Refine your search to only Report
open access

Groundwater Flow Model (GWFM) Development, Midnite Mine, Wellpinit, Washington

Description: This Report of Investigations (RI) is one of several describing work that has been completed by the U.S. Bureau of Mines at the Midnite uranium mine, Wellpinit, WA. Dean (in preparation) describes the entire project history. Four diskettes containing three archives compressed using WINZIP (or PKZIP) accompany the current RI. The ultimate purpose of this research effort was to develop a groundwater flow model (GWFM) for the Midnite Mine that can be utilized by the contractor preparing the Enviro… more
Date: 1996
Creator: Kirschner, Frederick E.
Item Type: Refine your search to only Report
open access

Reactivity in the South Spoils and Hillside Dump at the Midnite Mine

Description: The Midnite Mine is an inactive open-pit uranium mine located on the Spokane Indian Reservation in Washington State. Drill samples from two large waste rock dumps on the site, known as South Spoils and Hillside Dump, were collected with a Becker hammer drill and evaluated to determine potential of the rock to generate acid mine drainage (AMD). Waste rock at this mine contains both pyrite and uranium, and AMD effects are more complicated on this site than most in that uranium is soluble in both … more
Date: 1996
Creator: Moore, Bruce W.; Price, Jesse W. & Gardner, Ted
Item Type: Refine your search to only Report
open access

1995 Midnite Mine Radiation Survey

Description: Abstract: During the week of September 4, 1995, personnel from the U.S. Bureau of Mines conducted a Ra-226 survey at the Midnite Mine. One hundred thirty measurements were made on a rectangular grid with 150-m spacings. Concurrently, Shepherd Miller, Inc., took gross gamma readings in gR/h at the same grid points. In addition, the USBM collected 17 soil samples to be analyzed for radium, thorium, and potassium. The results of this survey are summarized in this report.
Date: 1996
Creator: Stroud, William P. & Droullard, Robert F.
Item Type: Refine your search to only Report
open access

Data Dictionary and Discussion for the Midnite Mine GIS Database

Description: Abstract: A geographic information system (GIS) database has been developed by the U.S. Bureau of Mines (USBM) for the Midnite Mine and surroundings in northeastern Washington State (Stevens County) on the Spokane Indian Reservation. The mine is an open pit uranium mine which has been inactive since 1981. The GIS database was compiled to serve as a repository and source of historical and research information on the mine site. The database supported USBM hydrological and reclamation research on … more
Date: 1996
Creator: Peters, Douglas C.; Smith, M. Antoinette & Ferderer, David A.
Item Type: Refine your search to only Report
open access

Real-Time Monitoring of Field Measurements for Mine Design: Greens Creek Mine, Admiralty Island, Alaska

Description: Abstract: Researchers at the U.S. Bureau of Mines conducted field investigations at the Greens Creek Mine in southeast Alaska for the purpose of validating computer design of mining methods and assessing real-time monitoring capabilities. The field study required the application of new technology because of the remoteness of the study site, the need for timely acquisition of data, and a limited budget for instruments and data acquisition. Various sensors were installed to monitor rock mass defo… more
Date: 1996
Creator: Orr, T. J. & Beus, Michael J.
Item Type: Refine your search to only Report
open access

Inflatable Devices for Use in Combating Mine Fires

Description: Abstract: The U.S. Bureau of Mines is conducting full-scale laboratory studies on the development of lightweight inflatable devices that can be used for rapidly isolating mine fire areas to allow for fire suppression and/or personnel escape. These inflatable devices were able to stop airflows of over 1,100 m3/min within several minutes. The remotely installed bag was designed to rapidly isolate the fire zone and to then serve, if necessary, as a containment form for the remote injection of low-… more
Date: 1996
Creator: Weiss, E. S.; Conti, R. S.; Bazala, E. M. & Pro, R. W.
Item Type: Refine your search to only Report
open access

3DTOM, Three-Dimensional Geophysical Tomography

Description: Abstract: 3DTOM is a DOS-compatible computer program developed by the Mines U.S. Bureau of for three-dimensional tomographic imaging of the subsurface at mine sites. The program uses the simultaneous iterative reconstruction technique (SIRT) to invert travel- time data and produce maps of wave velocity, or to invert amplitude data and generate maps of wave attenuation coefficients. Either seismic (compressional and/or shear) or electromagnetic (e.g., radio or radar) wave data may be used. Ray t… more
Date: 1996
Creator: Jackson, Michael J. & Tweeton, Daryl R.
Item Type: Refine your search to only Report
Back to Top of Screen