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By Sara J. Davenport

Hydrogen sulfite has been listed (1)3/ as a possible hazard in 50 occupations, many of which are in the mineral industries. The effects of its occurrence in the petroleum industry made themselves felt more than two decades ago, resulting in a comprehensive study (2) of the toxic gases from Mexican and other high-sulfur petroleum products. The mining industry, likewise, has had cause to guard against this gas. Enough hydrogen sulfide has been found in coal and some noncoal mines during normal operations to cause severe eye irritation, some serious illness, end even fatalities. It is usually a product of the decomposition of sulfur compounds and may be produced by burning explosives containing sulfur; the gas in harmful qauntities is formed by the use of block blasting powder or by the use of dynamite in blasting sulfide ores. Hydrogen sulfide is readily soluble in water, and enough may be released from water streams in coal and noncoal mining to cause fatal poisoning it is found sometimes in stagnant water underground, particularly where ventilation currents are absent, and great care must be exercised when accumulations of such waters are disturbed, as exposure to comparatively low concentrations of the gas evolved therefrom has caused fatal accidents.

Jan 1, 1945

By H. M. Kim, J. Rutqvist, D. W. Ryu

"Demand of high pressurized gas storage in underground rock caverns is increasing. Compressed natural gas (CNG) and compressed air energy storage (CAES) are one of the promising examples after since lined rock cavern (LRC) concept has been verified through in-situ pilot tests. Two key essential concerns of high pressured gas storage in underground rock caverns are mechanical stability of the cavern against high inner storage pressure and the risk of gas leakage from the caverns.In this study, we introduce our results of numerical simulations so as to investigate the potential of monitoring for gas leakage at a pilot facility for CAES in underground LRCs. The pilot facility was constructed at a comparatively shallow depth of 100 m, compared to the previous cases with several hundreds of meters, aiming at validating the feasibility of the LRC storage concept in which inner sealing liners, consisting of steel plate and concrete linings, are installed inside the excavated rock caverns (KIGAM, 2011). Compressed air may leak through either initial defects of inner containment liners such as imperfect welding regions and in-situ construction joints of the liners, or through structurally damaged points of the liners during the CAES operation where compression and decompression of the caverns are necessarily repeated and their structural robustness can be deteriorated.For this perspective, we carried out a coupled thermodynamic and geomechanical deformation analysis using TOUGH-FLAC simulator, and investigated the effectiveness of strain monitoring method in detecting mechanical failure of liners which may provide major pathways of air leakage. We therefore used an equivalent continuum model to relate the localized tangential strain to fracture permeability changes, which was developed in our early work (Rutqvist et al, 2012). In detecting and characterizing the leakage location, we tested a cross correlation technique using the synthetic pressure responses monitored in case of the failure of the inner liners. From the investigations, we showed that tangential strain, rather than radial, monitoring especially at the inner face of the sealing liners can be more effective in detecting the mechanical failure of the liners.In localizing the leakage point, we noted that the interface between the inner liners and surrounding rock may not be perfectly bonded so as to increase permeability through which any leaking air pressure may migrate more dominantly. We also demonstrated that the cross correlation of the time histories of pressure measurement especially at these interfaces can be useful in identifying the leakage point. These results may provide useful information in overall design of monitoring and alarming system of our upcoming CAES pilot facilities."

Jan 1, 2015

By Richard S. Della Valle

Sandstone and shale samples from the Morrison (Late Jurassic) and Dakota formations (Cretaceous) from northwestern New Mexico have been analyzed for the major elements Na, K, Fe and the trace elements Sc, Cr, Co, Rb, Sb, Cs, Ba, Hf, Ta, Th, iJ and the rare earth elements (REE) in whole rock and clay sized fractions by instrumental and delayed neutron activation analysis. The clay sized fraction clearly shows enrichment patterns and halo effects ; whereas, the whole rock fraction does not. Important elemental dispersion halos associated with uranium in sedimentary environments include the REE, Hf, and Sb. The distribution of these halos are due to a combination of complexation, chelation and the orignal paleoenvironments.

Jan 1, 1984

By Robert J. Greaves

High-resolution seismic reflection profiling can be used to evaluate detailed struc¬tural and stratigraphic features of coal pros¬pects. Since most coal prospects are relatively shallow (less than six hundred meters deep), the vertical and lateral resolution of seismic data can be significantly improved by high sampling rates in space and time. The case study present¬ed shows the effective use of seismic data in evaluation of the Wyodak coal at a prospective coal gasification site. The data were used to map the detailed structure and thickness of the coal and to search for lateral discontinuities, such as pinchouts and. faults. An important find was a paleochannel cutting across the base of the coal seam, which was later confirmed by drilling.

Jan 1, 1983

The characteristics of mineral resources and tailings resources in China are analyzed. Those tailings, which have double characteristics, can occupy land, pollute environment and even influence human habitat if they are not disposed in time. So pay attention to the comprehensive utilization of the tailing more and more both at home and abroad. The present situation and problems in comprehensive utilization of iron tailings in China are introduced by combine some practice experience, and have looked forward to the comprehensive utilization of iron tailing situation.

Jan 1, 2014

By Yeatman, Pope

FOR many years geologists have felt that mining companies should adopt a more liberal policy in the publication of their reports. The increasing usefulness of the geologist to the mining profession in recent years demands that consideration be given to this question. Prior to 1900, the call for geologists of high reputation by mining companies was probably mainly in connection with lawsuits arising from the interpretation of rights or ownership as defined by the "Law of the Apex," and from problems such as finding the continuation of the vein or whether the vein followed was the main one or a branch. Later, outside of legal questions, the most intensive and general use of their services arose from the search for oil. Geologists to determine the position of the formations

Jan 1, 1938

By Paul D. Chamberlin

There are many unit operations applicable to the processing of gold/copper ores. Deciding which are most applicable to your ore can be done using a series of tree diagrams. The diagrams show generalizations, not definitive rules. And the listing of process alternatives on the diagrams is very limited although there are dozens to choose from. Three questions help point the way to proper process selec-tion: 1. How much gold is in the ore? 2. How much copper is in the ore? 3, What is the cyanide consumption when leaching the ore?Halogens can also effectively leach gold ores and gold/cop

Jan 1, 1996

By H. F. Maulson

For the benefit of those who are not familiar with the history of the western Provinces-Manitoba, Saskatchewan, and Alberta-as regards our natural resources, a few words of explanation may be in order before taking up the consideration of the Mines Act of 1930. In 1867, The British North America Act was passed by the Imperial Parliament. That Act, which is our constitution, created a union between the provinces of Nova Scotia, New Brunswick, and Upper and Lower Canada (now known as Ontario and Quebec respectively) under the name of the Dominion of Canada. Provision was made therein for embracing other parts of Canada from time to time. That portion of Canada which today comprises the Provinces of Manitoba, Saskatchewan, and Alberta and the lands to the north of them, was then known as Ruperts Land and the North West Territory. In the year 1670, King Charles II had granted by Letters Patent to Prince Rupert and his associates, known as ?The Governor & Company of Gentlemen Adventurers of England, Trading into Hudson's Bay?, commonly known as the Hudson's Bay Company, the lands and territories therein described, being roughly all the lands adjacent to and west of Hudson's bay; also the gold and silver to be found or discovered therein and other rights as more fully described in said Letters Patent. The land so granted was called 'Ruperts Land'.

Jan 1, 1930

By R. R. Wells

As a part of the strategic mineral program, examining engineers of the Bureau of Mines collected samples several manganese properties in Colorado. As all of the ores were too low-grade to be acceptable to manufacturers of ferromanganese, beneficiation studies were required .to determine the amenability of the ores to concentration. Manganese in the form of impregnations in sedimentary beds is found in the Denver plains area a few miles east of the Rocky Mountain front. Deposits are reported to occur intermittently over a distance of more than 200 miles. The manganese oxides occur in beds of conglomerate or arkosic sand, generally accompanied by limonite. The Manganese and iron oxides,, however, usually are found in separate layers. Three samples were submitted for beneficiation tests, two samples from Buckley Field bombing Yang, Arapahoe County, and one from near Franktown, Douglas County.

Jan 1, 1952

By P. Barnes

EXACT accounts have been kept of the cost of these chimneys, and it may be a matter of some possible interest that the plans and details of cost should be laid before the Institute. The statement of cost herewith submitted does not give minute particulars of the weights or quantities of material used, although these are noted upon the company's books.

Jan 1, 1876

By Marco D. Boscardin, Kenneth A. Pidgeon, Adriane G. Boscardin

"Hollow bar tiebacks can offer an economical alternative to conventional solid bar and strand tieback systems for use in temporary excavation support construction. However, the limitations associated with the installation of hollow bar tiebacks require special attention during design, construction and load testing to verify conformance with conventional performance and proof testing criteria (PTI, 2014). In particular, providing a reliable free length is complicated by the 10-foot (3-m) -long, segmental, couplingto- coupling nature of the free length sheath in the hollow bar system, and addressing the fully grouted annulus of the bond zone and the free length zone at the end of installation are key concerns. In addition, it is often more convenient to install a greater number of more closely spaced, lower capacity tiebacks with the hollow bar system, compared to conventional tiebacks. This paper examines how these issues were addressed for a project involving a 60-foot (18-m) -deep sheet pile excavation through a highway embankment and a 70-foot-deep sheet pile and soldier pile and lagging excavation through a railroad embankment, both supported by a hybrid system of hollow bar tiebacks and hollow bar soil nails. The project involved approximately 300 tiebacks and 400 soil nails.INTRODUCTIONEngineers Construction, Inc. (ECI), constructed a pair of 32-foot (9.8-m) -wide (clear span), 30-foot (9- m) -high (21 feet (6.4 m) above the stream bed), cast-in-place concrete arch culverts as a design-build project for the Vermont Agency of Transportation (VTrans) in East Ryegate, Vermont. The new culverts replaced an existing 8-foot (2.4-m) -wide by 6-foot (1.8-m) -high cast-in-place concrete culvert under US Route 5 (RTE5), and twin, 2-foot (0.6-m) -wide by 5-foot (1.5-m) -high granite block culverts under the Washington County Railroad (WACR) alignment. The culverts convey Manchester Brook eastward, through the embankments for RTE5 and the WACR, on its way to the Connecticut River. The Connecticut River is located approximately 100 feet (30 m) east of the WACR embankment. The existing structures were undersized and backed up water behind the embankments during high flow events; and often trapped debris that flowed down the brook and became clogged. The existing culverts also had cracks and openings that have resulted in the loss of ground into the culverts and the formation of sinkholes in the sides of the embankments. Moreover, the reason for the large cross-sectional dimensions of the culverts was to make them of sufficient size and openness to encourage the migration of fish up the stream to spawn. The culvert through the RTE5 embankment is 144 feet (44 m) long, and the culvert through the WACR embankment is 128 feet (39 m) long, with a 57-foot (17.4-m) -long by 32–foot (9.8- m) -wide by 17-foot (5.2-m) -deep 10 feet (3 m) deep above the stream bed) open channel section between the two culverts. A plan view of the culvert alignment is presented in Figure 1."

Jan 1, 2016

By Dale S. Preece, Ruilin Yang

"Air-decks are often employed for presplitting along the final highwall of a blast and are sometimes also included at the bottom or in the middle of explosive columns in the production portion of a blast. Shock wave physics is an important part of air-deck behavior since the bulk explosives in the column impart a shock into the air-deck where the air shock then passes through the air-deck at a rapidlyattenuating velocity. Through both high-fidelity modeling and shock physics theory it is shown that theresulting pressure in the air-deck is two orders of magnitude less than the detonation pressure of theexplosive."

Jan 1, 2017

By C. Aimone-Martin, C. Dowding, M. Jern, J. Gjødvad

This article compares percentages of compliance for six national standards to demonstrate how these standards vary on-site in a real project. This, to the best of the authors' knowledge, has not been accomplished before. Different standards not only vary in allowable amplitudes of induced vibrations but also in how they are measured (transducer location, transducer orientation, frequency content of vibration, etc.). Thus it is not straightforward to compare the permissible values of induced vibrations with each other. This challenge of comparison is overcome in this project by instrumenting a structure with multiple transducers according to different national standards and comparing the degrees of compliance. Compared herein are compliance with standards used in United States of America, Germany, Great Britain, France, Austria, and Sweden. Averages of the percentage of compliance and ratios of measured vibration amplitudes for all six national standards are compared both in tabular and graphical form for 20 blasts at the Aitik mine northern Sweden. It is the largest open pit mine in Europe and blasts are atypically large with more than 1000 kg charge per hole and several hundred holes per blast, lasting 3-5 seconds. Results show that percentages of compliance can vary by as much as 2 to 75 % for these blasts at this structure. The overall project is a cooperative effort between EFEE (European Federation of Explosives Engineers) and ISEE (International Society of Explosives Engineers), supported by more than 17 persons from 8 different countries. At the present the experts are the four authors of the present paper and Dr. Robert Farenfield, Dr. Nathan Rouse, Douglas Rudenko, Brent Meins, Kenneth K. Eltschlager, Karin NorénCosgriff, Travis A. Davidsavor, Vitor Luconi Rosenhaim, Johannes Kutschera, Bernard Thierry, Thomas Moser, Cory Loukedis, and Keith Best. The project began with a literature study and a survey including an evaluation of the answers provided by members of EFEE. Results were presented at the ISEE conference in Denver 2020 as well as the EFEE conference in Helsinki in 2019 (Gjødvad & Jern, 2019; 2020). The second part of the project was initiated in May 2021 with installation of 7 seismographs from two different manufactures, 3 cracs gauges and 2 microphones on a building at the Aitik mine in northern Sweden. The third part of the project has moved to the United States. Two residential structures adjacent to quarries are being monitored in Michigan and Ohio. Installation and monitoring began in March 2023 and are expected to continue for 6 to 12 months. In addition to the objectives of phase two the 2023 study includes calculations of global wall strains from measured velocity time histories and measurement of response of existing cracks to vibratory and climatological effects

Jan 1, 2024

By J. D. Davis

THIS report gives results of an investigation of the carbonizing properties of the following eastern Kentucky coals: Elkhorn No. I bed, No. 28 mine, Wayland, Floyd County; Elkhorn No. 2 bed, Turner No. 5 mine, Drift, Flood County; Leatherwood (Haddix No. 5) bed, Leatherwood mine, Leatherwood. Perry County; and Harlan bed, Path Fork mine, Path Fork, Harlan County. The carbonizing properties were determined by Bureau of Mines-American Gas Association (BM-AGA) tests at 800° and 900° C. and by expansion tests in the sole-heated oven. Plastic properties were determined by tests in the Gieseler and Davis plastometers. The coals were tested singly and as blends with 20- and 30-percent low-volatile Pocahontas No. 3 coal. The dry, mineral-matter-free, fixed-carbon content of the carbonizing samples ranged from 56.7 percent for Elkhorn No. 2 to 59.7 percent for Leatherwood, and the heating values on the moist, mineral-matter-free basis ranged from 14,420 B. t. u. per pound for Elkhorn No. 2 to 14,720 for Harlan. The percentage of ash ranged from 2.9 to 6.1. The fluidity of three coals, measurer. In the Gieseler plastometer, ranged from 230 to 670 dial divisions; the fluidity of Elkhorn No. 2 could not be determined by this method. Blending lowered the fluidity of each coal; the fluidity of the blends containing 20 and 30 percent Pocahontas No. 3 ranged from 16 to 53 and from 8 to 17 dial divisions, respectively. Agglutinating values determined on silicon carbide-coal mixtures in the ratio 15:1 ranged from 3.8 to 6.3.

Jan 1, 1952

By Nathan Brandner, Denise Levitan

For many decades, a potash operation in Saskatchewan, Canada, has maintained storage impoundments for mine tailings and process-related mine water. The mine water is a concentrated aqueous solution, with most of the total dissolved solids (TDS) consisting of sodium and chloride. Although the facility has a system of slurry walls and collection/ diversion ditches, the mines monitor the surface water and groundwater around the tailings storage facilities (TSFs) for releases. Groundwater on the western side of the facility has been measured as having concentrations of TDS, magnesium, sodium, chloride and sulfate above provincial drinking water quality objectives. In addition, electromagnetic surveys have shown high electrical conductivity in that area. For these reasons, studies were undertaken to investigate the extent of the high TDS concentrations in groundwater and whether the elevated concentrations were related to the TSF. Chloride and TDS concentrations in groundwater monitoring wells were used to interpret the transport of high-TDS mine water moving along three interpreted zones of elevated TDS west from the facility (Fig. 1). The zones of elevated TDS concentrations corresponded to the areas of high conductivity identified by the geophysical surveys. These results suggested that mine water could be emanating from the TSF and potentially require remediation. However, the interpreted orientation of the high-TDS groundwater and apparent flow paths were perpendicular to the direction of groundwater flow in the area. The fundamental conflicts in these interpretations led to a reexamination of the conceptual site model for the distribution of potential mine water releases. Although the data examination and visualization made it clear that TDS concentration alone was not a reliable indicator of mine water release, there was still concern about elevated chloride concentrations. To further evaluate high TDS and chloride concentrations, several background area wells were installed northwest of the facility, beyond where mine water impacts could occur (Fig, 2). The background wells had highly variable chemical compositions. One of the wells had an elevated TDS concentration with magnesium and sulfate as the dominant ions with chloride concentrations above drinking water objectives, similar to the high-TDS wells west of the facility. The results of the background groundwater investigation (major ion chemistry) were supported by the scientific literature on prairie sloughs throughout the North American Great Plains. These sloughs are small, shallow and sometimes seasonal wetlands found throughout the region. Seasonal cycling in precipitation/ runoff and evapotranspiration result in accumulation and mobilization of salts, especially sulfate-bearing phases such as gypsum. The long-term dynamics of these features, which are common on the property west of the facility, likely control the TDS concentrations and compositions in shallow groundwater rather than mine water migration from the site. The conclusions from this investigation led to a better understanding of the lateral distribution of potential TSF-related impacts versus background groundwater chemistry. Presentation of the data, including the visualizations of different water compositions, to the provincial regulatory agency representative allowed the facility to propose an optimized annual groundwater monitoring plan with reduced sampling frequency and annual sample count. This study underscores the importance of critical evaluation and comparison of various data types, including background levels, from a particular site and the iterative approach to developing and supporting robust conceptual site models for optimizing project outcomes.

Jul 1, 2025

By Rob Farnfield, Ben Williams, Ashley Haslett, Diane Cartledge

Major accidents that occur within our industry are often tragic and expensive, damaging reputation and threaten the livelihood of the business. There isn’t anything in them that can be seen as positive for those that experience them. They undertake what are usually very painful, detailed and time consuming investigations to discover how the incident occurred and what needs to be done in the future to prevent similar incidents occurring. Many admirably choose to share the lessons learnt through industry organizations such as SAFEX International so that we can all have the opportunity of preventing similar incidents from occurring within our own organizations.

Jan 1, 2016

By J. A. Kosek

Work has been carried out under Bureau of Mines Contract HO 395132 to develop improved sensor cells for use in direct-reading detectors and diffusion exposure meters. A pumped CO sensor cell was developed which has a shorter response time, improved temperature cycle characteristics, and improved linearity and stability at high CO concentrations. Diffusion CO sensor cells have shown good response level stability and linearity up to 1000 ppm. In addition, a new sensor cell catalyst has been developed for NO2 sensor cells which has a much shorter response time and improved response stability characteristics.

Jan 1, 1982

By D. F. Scott

"DEFINITION OF THE REGION AND ITS BOUNDARIESTHE REGION of Western Canada covered by this re-port lies between the Precambrian rocks of the Canadian Shield and the structurally deformed rocks of the eastern Cordillera, extending northward from the international border to the 60th parallel. It is some 487,000 square miles in area, with a total sedimentary fill of about 535,000 cubic miles0>. It includes parts of the prairie provinces of Manitoba, Saskatchewan and Alberta and the northeast corner of British Columbia and forms part of the geological region known as the Interior Platform, commonly referred to as the Western Canada Sedimentary Basin. The bedrock comprises carbonates and evaporites of Paleozoic age that lie on Precambrian crystalline rocks and are over-lain by a relatively thick blanket of Mesozoic and Tertiary elastic rocks. The nearly flat-lying bedrock, covered by a thick mantle of glacial drift, forms the Interior Plains physiographic province."

Jan 1, 1970

By Joseph L. Condon

High-speed movies were taken of crater experiments in two-dimensional plates of Tennessee marble to study craters being formed primarily by stress-wave action. The contribution of gas action to the cratering process was minimized because the two-dimensional models did not contain the expanding gases from the explosive. Four burdens were studied for solid plates and one burden for a segmented plate. After cratering, the plates were reassembled for dye penetrant studies of fracturing. Flyrock velocities were calculated and related to the degree of fracturing, and compared with those from quarry shots. In general, the smallest burdens produced the highest flyrock velocities and the least amount of fracturing. Flyrock velocities compared favorably with initial flyrock velocities in quarry blasts, but did not show step accelerations due to gas effects as did the quarry blasts. The test with a segmented plate was used to simulate cratering in a jointed material and showed that stress-wave effects can be important for crater formation in jointed rocks.

Jan 1, 1972

By M. Uszko

The climatic area in which Poland is located requires heating the ventilation air at intake shafts during the winter season. Air heating of the intake shaft should ensure safe operation of hoisting devices; while at the same time it also affects the conditions of the mine environment. The paper presents the issues of shaft heating in coal mines in terms of the mining law, the effect on the conditions of the mine environment and heating technology solutions used in the mines of Kompania Weglowa S.A. (KWSA).

Aug 1, 2013