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By R. W. Van Dolah

A premature detonation of an explosive charge occurred on January 30, 1961, at a face being prepared for blasting in the underground Jefferson Island Salt Mine, Diamond Crystal Salt Co., Jefferson Island, Iberia Parish, La. The accidental blast injured the powderman fatally; his helper was injured also, but recovered. The accident represents the first fatality reported to the Bureau of Mines in connection with the use of ammonium nitrate-fuel oil (AN-FO) blasting agents in underground mining in the United States. Representatives of the Bureau of Mines Explosives Research Laboratory, Pittsburgh, Pa., and field representatives of the Bureau's Health and Safety Activity conducted the investigation, upon request of the manufacturer of the ammonium nitrate being used and with concurrence by the mine management.

Jan 1, 1962

By J. R. Patts, A. B. Cecala

"After industrial sand has been mined and processed, the finished product is typically loaded into small bags of 45 kg (100 lb) or less, large bulk bags of 454 to 1,361 kg (1,000 to 3,000 lb), or vehicles such as trucks or trains for transport to end users. As the sand is being transferred and loaded, dust can be released into the work environment, potentially exposing workers to respirable crystalline silica. A number of control technologies have been developed and utilized in an effort to reduce dust liberation during loading operations. For bulk loading into trucks or trains, the U.S. National Institute for Occupational Safety and Health (NIOSH) evaluated one of these technologies, the Dust Suppression Hopper (DSH), at two industrial sand processing plants. Results from these case studies show that the DSH reduced airborne respirable dust levels by 39 to 88 percent, depending upon the product size being loaded.IntroductionInhalation of respirable crystalline silica dust can lead to the development of silicosis, a disabling and potentially fatal lung disease. Once contracted, there is no cure for silicosis, so the goal is to prevent the development of the disease by limiting exposure to respirable dust containing crystalline silica at or below the exposure limit of 50 µg/ m3 recommended by the U.S. National Institute for Occupational Safety and Health (NIOSH, 2002). At industrial silica sand operations, the product contains high levels of crystalline silica, so effective control technologies are needed to minimize the respirable dust exposure of workers.NIOSH, in partnership with the Industrial Minerals Association–North America, published a dust control handbook (NIOSH, 2012) focused upon control technologies for industrial- mineral mining and processing operations. One chapter in this handbook discussed technologies for controlling dust liberated during bulk loading, including telescoping loading spouts, dust collection systems for loading spouts, enclosures for load-out areas and a newer technology known as Dust Suppression Hopper (DSH)."

Jan 9, 2018

By Tom Dettweiler, Robina Sharpe, Wright. Michael

The International Seabed Authority and a number of countries have or are in the process of developing environmental impact assessment guidelines and legislation for seafloor mineral development. The formal decision to grant a project an environmental permit is based on an environmental and social impact assessment (ESIA), culminating in an environmental impact statement (EIS). The EIS needs to be supported by sufficient data upon which an assessment of impacts can be made and mitigation measures developed. Given the remote locations of many seafloor prospects, collection of sufficient environmental data to inform an EIS is often a difficult, expensive and lengthy process.

Sep 1, 2014

By Edward L. McHugh, Louis J. Denes, Jami M. Girard

A prototype portable hyperspectral imager that operates in the visible and near-infrared ranges of the electromagnetic spectrum was field tested at an open-pit mine. The tests were sponsored by the Spokane Research Laboratory, National Institute for Occupational Safety and Health, as part of an investigation of remote sensing technologies for use in detecting and monitoring conditions in surface mines that could lead to catastrophic slope failure. The spectro-polarimetric imager, built at the Carnegie Mellon Research Institute, employs an acousto-optical tunable filter (AOTF) to control wavelength, a phase retarder to measure polarization signatures, and a digital camera and computer to capture data. The spectral range of the instrument is 450 to 1000 nm at 10-nm intervals. High-resolution hyperspectral images of highwalls, outcrops, hand samples, and drill core were collected in the field. Spectra from the images closely matched those of specific minerals present and were used to classify the images. The field tests were designed to examine the feasibility of using spectral imaging to assist in compiling objective geologic maps of mine highwalls and other hazardous slopes. Results illustrate the capability of the method to discriminate materials within the image, validating the concept of simplified spectral imaging. A contributing factor in many slope failures is the presence and distribution of mechanically incompetent, clay-rich altered rock in slope faces. Spectral features of clays and other minerals are more distinctive in the short-wave and mid-infrared part of the spectrum; the capabilities of the instrument need to be extended into this range to apply the AOTF-based technology to common geologic materials. A field-portable hyperspectral imager could find broad application in remotely identifying diverse materials from solids and coatings to gases.

By J. R. Nawrot

Reclamation of potentially acid producing coal processing waste requires a 4-foot cover, and/or treatment to allow vegetation establishment. If not planned properly, soil covering alone does not prevent refuse acidification or formation of acid seeps. Adequate neutralization enhancement prior to soil covering can maintain an alkaline environment in the soil refuse interface and prevent acidification. Direct vegetation establishment using only limestone amendment (without soil cover) can successfully reclaim aged and weathered fine (Blurry) and coarse (gob) refuse if adequate neutralization treatment is provided for the oxidized surface zone. Acid seeps, representing an "after-the-fact" verification of an imbalance of acid-base equilibrium may also be corrected using upslope alkaline recharge techniques. Concentrated alkaline recharge pools have been constructed above previously soil covered acid gob at the Peabody Will Scarlet Mine to abate acid seeps. Preliminary monitoring results (1989-1992) from a concentrated alkaline recharge pool demonstration project in the Pit 4 area of the Will Scarlet Mine have documented a 50 to 80 percent reduction in acidity in the principal recharge pool groundwater zone. A 22% reduction in acidity has occurred in the primary seeps located downslope from the alkaline recharge pools. The initial improvements in water quality are seen as a positive indication that groundwater acidity will decrease further and amelioration of the acid seep will continue.

Jan 1, 1993

By M. B. Balachandra

A three-dimensional finite element analysis was performed of an instrumented section of a double-entry coal mine in order to provide a comparison between field measurements and existing analytic techniques. The BMINES computer code was used to perform the analysis. The sequence of excavation of the entries was considered, as well as the installation of rock bolts and cribbing during the mining cycle. The materials In the region under investigation were idealized into four rock types and coal. The rocks were assumed to be isotropically elastic, perfectly plastic. Coal was represented by an elastically anisotropic (transverse isotropy) and plastically isotropic model. A fracture yield criterion of the Coulomb form was used for all materials. The strength and stiffness of all materials were substantially reduced from available laboratory data to account for in-situ properties. Qualitative trends and stress distributions obtained from the calculation were found to be reasonable. However, computed displacements and closures were greatly exaggerated and an excessive degree of inelastic deformation was indicated in the coal, especially adjacent to the excavated faces. It was established that both these effects were the result of an excessive reduction in the strength and stiffness of the materials. The analysis underscores the need for three-dimensional calculations by identifying a number of important structural response parameters that would be either outside the scope of, or misrepresented by, two-dimensional analyses. The analysis also emphasizes the need for comprehensive and accurate measurement of material properties in order fully to exploit the power of the analytical techniques to generate reliable predictions.

Jan 1, 1976

By D. P. McDonald

"IntroductionTHE PURPOSE of this paper is to present .a summary of the evidence given before the Petroleum and Natural Gas Conservation Board in support of applications to it for permits to export natural gas from Alberta.I will attempt to be objective in my statements, despite the fact that my main interest in the hearings before the Board was to advance the interests of my own clients, the Westcoast Transmission Company, Limited.The hearing of the export applications •commenced before the Board in January, 1950, with the .application of the Westcoast Transmission Company. Joint hearings were commenced in September, 1950, and completed on December 14th, 1951. The Board heard evidence in support of six applications for export, one application to build a gathering system in Alberta, and three interveners, the .latter being the City of Calgary, the local gas companies, .and the coal interests, including both operators of coal mines and the Unions.The evidence comprised better than 8,400 pages, over two million words, and occupied 92 days before the Board.The Interest in Natural GasThe natural gas industry is one of the newer industries. It is not yet twenty years •old. In the United States, the expansion •of pipeline facilities has been phenomenal in the last fifteen years, and particularly in the last three years, when a total of over two billion dollars was invested in pipeline facilities. There are approximately 250,000 miles of gas transmission pipelines in the United States at this time, with additional lines constantly being pressed."

Jan 1, 1952

By D. E. Kirby

In line with the Bureau of Mines' goal of providing technology to maintain a supply of minerals adequate to meet national economic and strategic needs, a method for recovering chromite from lateritic materials was investigated. Laterites are a large resource of Ni, Co, and Cr, critical metals of which the United States has insufficient domestic sources. A roast-leach method was developed by the Bureau to extract nickel and cobalt from domestic laterites. A concurrent effort was made to recover chromium from either unprocessed laterites or the leach residues. This report characterizes laterites and laterite leach residues. It describes a chromite recovery procedure using conventional industrial beneficiation equipment for sizing, low-intensity magnetic separation, and gravity concentration. Concentrates containing 20.0 to 22.4 pct Cr (29.0 to 32.7 pct Cr203) and with a 1.6:1 to 1.9:1 Cr-Fe ratio were recovered from laterites and residues containing 1.3 to 2.5 pct Cr with recoveries exceeding 50 pct. Because of their low grade and fine size, these concentrates would be suitable for preparing chromium chemicals. The direct beneficiation of laterites for chromite recovery resulted in the minerals containing nickel and cobalt concentrating in slime products. No iron oxide coproducts of acceptable grade were recovered from either laterites or residues.

Jan 1, 1982

By J. Châteauneuf, R. Dupéré, D. Mrabet

"In gold processing plants, it is common to start gold cyanidation in the grinding circuit by simple cyanide addition or as a result of recycling residual cyanide. In such cases, advantages such as a decrease in gold lockup and reduced leach time have been noticed. The prevailing conditions in grinding circuits such as intense mixing, particle breakage and friction or high temperature are quite different from those found in tanks and so is the resulting cyanidation behaviour. To gain a better understanding of the cyanidation behaviour in mills and of the pertinence of cyanide addition in grinding circuits, lab tests were conducted using an industrial ore from Canadian Malartic mine. In this study, the effects of different parameters on cyanidation in grinding circuits were examined; parameters such as such as temperature, dissolved oxygen, cyanide concentration and pH. The results showed that the kinetic benefits of high temperature in the mill can overcome the low dissolved oxygen concentration thus leading to an overall gold dissolution kinetics improvement for temperatures up to 50°C. However, gold leach in the studied grinding circuit at lab scale caused an increase in cyanide consumption with a higher generation of iron cyanide and SCN-. These results were confirmed by tests in the Canadian Malartic plant where the cyanide addition was moved from the SAG mill to the leaching tanks resulting in a 20% savings in cyanide consumption.IntroductionCyanidation in grinding circuits can benefit gold processing by decreasing gold lockup and by reducing leach time. However, other aspects regarding gold and cyanicide dissolution come into play in the conditions prevailing in grinding circuits. Indeed, high turbulence, high temperature, recycling load, friction and particle breakage make cyanidation behaviour in grinding circuits different from in-tank cyanidation (Marsden and House, 2006). In several cases, cyanide in grinding is limited to a very low level or completely avoided such as in circuits with gravimetric separation, for ores requiring oxidative pretreatment or for preg-robbing ores. In other cases, water management imposes a certain recycling of residual cyanide. This problem is generally addressed by a case-by-case approach. However, the chemistry of cyanidation in mill circuits is worth investigating in order to assess the advantages and disadvantages."

Jan 1, 2016

By John P. Davis

The use of conventional, circulatory air rotary and fluid rotary, cased and uncased drilling methods in the vicinity of sensitive infrastructure can have deleterious effects on the ground conditions surrounding and supporting structures and the structure itself. Furthermore, the use of these conventional methods offers the engineer or contractor little information about the condition of the subsurface during geotechnical applications. Conversely, sonic drilling measurements and samples can be used to evaluate actual conditions during the progress of exploration and construction across a given site. This paper will discuss the history and properties of sonic drilling and explore case histories of geotechnical applications for the advancement of boreholes within vulnerable structures and on sensitive sites for several recent infrastructure projects ? a tunnel and railroad project, a dam grout curtain project, a bridge micropile exploration project and a tunnel instrumentation project. Project summaries will discuss the advantages realized when the application of sonic drilling techniques demonstrated superior accuracy, quality control, efficiency, productivity, penetrability, waste minimization and adaptability when drilling adjacent to or within existing infrastructure. Finally, the discussion will address the current testing and application of sonic drilling to the installation of micropiles, earth retention anchors, grout injection and instrumentation installation where the quality control benefits provided by the inherent soil cores, measurement while drilling systems, accuracy and non-destructive production drilling features will be advantageous.

Jan 1, 2006

By McHenry Mosier

This is the fourth progress report in the series on the use of detachable rock-drill bits in the metal mines of the United States. It contains comparative statistics and costs or drilling at eight mines not reviewed in previous reports, comparison of the use of detachable bits at small mines and large mines, a discussion on the life of drill rods, and general conclusions derived from an analysis of the rock-drilling practice at all the mines investigated on this survey. This paper completes the descriptions of operating practice in rock drilling at individual mines. Data on drilling practices at 28 mines are given in appendices I and II and drilling costs are shown in appendix III. Research in the fundamentals of rock drilling, including the use of detachable bits, has been undertaken by the Bureau of Mines in its testing adit at Mount Weather, Va. Reports on the progress off this investigation will be issued when results warrant their publication.

Jan 1, 1937

By R. B. Alke

Request to Mine Beneath Bridge The Jabs Run Bridge is a reinforced portland concrete arch filled bridge located on WV Bouts 7 near Pentress, WV. The bridge has a span of 22.9 m (meters) and a height of 4 m above normal pool elevation to the underside of the center of the arch (See Pig 1). The bridge is a two lane structure with a width of 6.86 m. The structure is over 50 years old Wing been built in 1929 and is owned by the Department (WV Department of Highways).

Jan 1, 1984

By G. N. Schrauzer

Work has been carried out in the development and testing of carbon monoxide (CO) detection devices which use silica-gel impregnated with metal salts. If carbon monoxide is present, the ?detection gel? (the treated silica-gel) changes from a yellow to a blue-green or blue color. The detection gel "regenerates", i.e., returns to its original yellow color, within 4-24 hours after removal from air containing CO. The detection gel exhibits a threshold of CO response which can be adjusted over a wide range of CO concentrations, typically from 50-500 ppm in air. The preparation of detection gel using salts of palladium, molybdenum and copper is described. Also reported are the results of testing the detection gel&apos;s response to carbon monoxide under varying conditions of temperature and humidity and in the presence of some potentially interfering gases. Low levels of hydrogen sulfide (~ 5 ppm)1 nitrogen dioxide (< 7 ppm), and acetylene (> 200 ppm) were found to affect the detection gel. Temperature and humidity were also found to affect the detection gel&apos;s response. Increasing temperature shortens the gel?s response time while increasing the humidity delays the gel?s response and alters the threshold of the gel. A brief discussion of the further research and development necessary to stabilize the detection gel?s desirable characteristics is included. Descriptions of testing equipment and procedures are covered in detail.

Jan 1, 1978

By Takahiro Kubo, Katsunori Yamaguchi, Hidehiro Sekimoto

Equilibrium relation between B2O3 slag, RExOy-B2O3 (RE = rare earths) slag and Fe-C alloy formed by melting treatment of neodymium magnet and B2O3 was investigated. When neodymium magnet was melted together with B2O3 and Fe-C alloy in carbon crucible, 3 liquid phases of B2O3 slag, RExOy-B2O3 slag and molten Fe-C alloy formed and clearly separated by the difference of the specific gravities. In the case that excess amount of Cu was also introduced in that system, molten Cu phase additionally formed. Almost all amount of RE were concentrated in RExOy-B2O3 slag. The concentration of RE in RExOy-B2O3 slag increased with the decrease of the melting temperature. While chromium, phosphorous, nickel, cobalt, and copper were concentrated in molten Fe-C alloy, silicon and aluminum were distributed in B2O3 slag and RE2O3-B2O3 slag.

Jan 1, 2014

Safe underground mine backfilling with hydraulic fill requires efficient fill drainage and stable fill retaining walls or bulkheads. If any or both the above two requirements are not satisfied, such a backfilling operation creates unsafe conditions and may lead to backfill retaining wall failures. Mine backfill retaining wall failures are always associated with economic losses, fatalities and interruption to mine production. Mining industry wants to either reduce or eliminate these fill retaining wall failures. The fill retaining wall failures could be effectively avoided through the use of fibre reinforced shotcrete fill retaining walls and engineered drainage systems through the retaining walls. This paper presents the experience of the author in developing, implementing, and monitoring several hundred fibre reinforced shotcrete fill retaining walls at a mine in Australia with the highest safety standard. The details on the mine backfill drainage system and fibre reinforced shotcrete fill retaining wall designs are also presented.

May 1, 2007

By Adrian Coombs, Paul Magowan, Derek Zoldy

Continued development and intensification are fuelling the urgent need for new trunk infrastructure within The Regional Municipality of York and throughout the Greater Toronto Area. Permitting of these projects is increasingly subject to public scrutiny to severely restrict dewatering through construction technologies and the requirement for a comprehensive and effective Environmental Management Plan. Three current projects: one on the York Durham Sewage System and two in the City of Toronto 1.Conventional Design, Tender, Award: 4,150m (13,600 ft.) 2.7m (9 ft.) finished interior diameter soft ground tunnel for York Region’s YDSS Interceptor Trunk Sewer 2.Negotiated Contract: 3,800m (12,500 ft.) 3.5m diameter (11.5 ft.) rock tunnels for Enwave’s environmentally sustainable and innovative chilled water system in downtown Toronto 3.Conventional Design, Tender, Award: 2,200m (7,200 ft.) 3.3m diameter (10.8 ft.) rock tunnel for reinforcement of Hydro One’s primary hydro feed in the downtown core of Toronto These projects exemplify issues such as: EPB tunnel and sealed shaft technologies Substantial permitting requirements associated with dewatering Mitigation of rock creep Congested downtown rights-of-way Deep shafts and confined working compounds Unique scheduling and cost benefits when Owner, Contractor and Consultant can work together cooperatively.

Jan 1, 2007

By Harold M. Smith

This report presents a complete qualitative picture of knowledge of the composition of petroleum as of April 1965. The material is presented in detail on two imaginative maps--one, the Hydrocarbon Hemisphere, depicts the hydrocarbons that have been identified in petroleum; the other, the Heterogeneous Hemisphere, shows the sulfur, nitrogen, and oxygen compounds that have been found. All compounds are placed on the maps according to boiling point. The accompanying text illustrates by structural formulas the several types of hydrocarbon and nonhydrocarbon compounds identified, presents some quantitative data, and points out the possible geochemical significance of a number of the compounds. The possibilities of the Petroleum World of the future are discussed as a function of needed research,

Jan 1, 1966

By Harold M. Smith

This report presents a complete qualitative picture of knowledge of the composition of petroleum as of April 1965. The material is presented in detail on two imaginative maps--one, the Hydrocarbon Hemisphere, depicts the hydrocarbons that have been identified in petroleum; the other, the Heterogeneous Hemisphere, shows the sulfur, nitrogen, and oxygen compounds that have been found. All compounds are placed on the maps according to boiling point. The accompanying text illustrates by structural formulas the several types of hydrocarbon and nonhydrocarbon compounds identified, presents some quantitative data, and points out the possible geochemical significance of a number of the compounds. The possibilities of the Petroleum World of the future are discussed as a function of needed research,

Jan 1, 1966

By Robert M. Doerr

The research objective was to determine the effect of aluminum alloy additions on the oxidation behavior of cobalt-nickel alloys. Thirty high-purity alloys were reacted with 02 at 0.5 atm at 1,351°, 1,389°, and 1,429° K in a volumetric apparatus for about 300 min. The alloy compositions consisted of Co-Ni master alloys (0, 22, 50, 70, 91, and 100 wt pct Ni) with aluminum additions of about 0, 1, 2, 4, and 8 wt pet. Large early deviations from, or changes in, the parabolic rate constant were encountered, but in most cases, the reaction rate declined approximately in accordance with the parabolic rate law. A sharp peak in the parabolic oxidation rate constant was observed for specimens containing a to 22 percent nickel and 1 to 2 percent aluminum at 1,351° K, and the rate constants for these compositions were lower at the higher temperatures. Specimens containing 8 percent aluminum reacted far more slowly than did any of the others.

Jan 1, 1971

By John K. Owens, Wayne L. Howie

Mobile roof support (MRS) machines are used as roof support during pillar recovery in retreat operations in lieu of wooden posts, cribs, or hydraulic props. A Mine Safety and Health Administration-permissible load rate monitoring system was developed for the MRS by researchers at the Spokane Research Laboratory of the National Institute for Occupational Safety and Health. The system uses a dedicated embedded processor to monitor changes in pressure inside the hydraulic cylinders of the MRS through multiplexed data acquisition channels and converts these pressure changes to load rates that sequentially activate three load-rate-indicator lights mounted on the machine. Each light represents a different loading rate to alert mine personnel to dangerous conditions during pillar extraction.