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When the Organic Act of 1910 established the Bureau of Mines within the Department of the Interior, the Bureau's programs involved only health and safety research and, education, and fuels testing. As the Federal Government's primary agency for research in minerals, the Bureau has expanded its scientific and technological investigations to mining, processing mineral substances, eliminating occupational health and safety hazards in the mineral industries, economic development, and resource conservation. Today, Bureau activities cover a broad spectrum of programs for meeting the diverse (and sometimes conflicting) needs of mineral industries, government, and the public. In the 1960's, the Bureau initiated programs to resolve environmental problems associated with past mining and mineral processing. In the 1970's, the energy crisis raised the national consciousness concerning our limited supplies of domestic mineral and fuel resources. Dependence on foreign sources of raw materials critical to our national economy and competition from other countries for these world supplies stimulated the need to conserve and use with intelligence the Nation's minerals, metals, and fuels.1

Jan 1, 1977

By Samuel P. Polack

This report reviews investigations to determine the fire hazard in coal mining when using flammable petroleum hydraulic oils to actuate mining equipment and summarizes research by the Bureau of Mines and industry on fire-resistant hydraulic fluids. Tests were established to evaluate fire resistance and the necessary characteristics to assure adequate service when fire-resistant fluids are used to replace petroleum hydraulic oils. The research was conducted in the laboratory and field trials under actual operating conditions in underground mines. Bureau of Mines Schedule 30 became effective December 17, 1959; the first approval was granted on February 18, 1960, and the twelfth was granted on March 17, 1961. The approvals include nine ready-mixed (by the producer) fluids and seven concentrates to which water is added by the user according to instructions from the producer. Seven synthetic-type fire-resistant hydraulic fluids submitted by two producers are also approved. Over 100 coal mines are now using water-in-oil emulsion-type fire-resistant hydraulic fluids in varying degrees from a trial in one machine to all the hydraulic equipment in an entire mine.

Jan 1, 1961

By Nils A. Eilertsen

This Bureau of Mines report describes the unit cost procedure for estimating direct development costs within a cave block in an undercut block caving mine. Costs of supervision, labor, equipment, and supplies are combined to build a unit cost for each type and size of mine development opening in the block. These costs are then combined to estimate the direct cost for developing a ton of ore. Operating data from several domestic metal mines are combined with a hypothetical mining system to illustrate the costing procedure.

Jan 1, 1975

By Ehab Gomaa, K. A. El‑Nagdy

Backfilling material such as tailing (mine wastes) mixing with cement or gypsum has grown throughout the world’s underground mines. However, despite their growing popularity, the typical hydraulic and mechanical fill types utilized in many mines still exist. Deep underground mining has increased due to the lack of commercial minerals nearby. Mine wastes were considered the main part of backfilling to prevent environmental pollution, ground subsidence after mine abandonment, and mine collapse during deeper extraction phases. The cemented backfill technique is the principal technique used in underground mines, which include cement with fly ash and/or filter dust, cement with tailing material and fly ash, gypsum with fly ash, and synthetic anhydrite with fly ash and have been reviewed. It has concluded that a backfilling material must be selected based on further goals, available material near the mine site, and economic factors. This paper analyzes different backfill material mixtures to create a technique that will increase safety in underground mining conditions and foresees an appropriate formula that gives high uniaxial compressive strength. The multiple linear regression (MLR) on the collected data from the experimental works to construct the relationship between the uniaxial compressive strength (UCS) of the mixture and the components of the backfilling and the prediction formula for expected compressive strength was obtained. The results revealed that the predicted regression equation was robust and reliable to predict the (UCS) for the new components of the filling (cement (CE), filter dust (FD), water content (WC), and time (T)).

Oct 3, 2023

By William L. Crentz

This study of the preparation characteristics of the coals in Indiana County, Pa., is the second in a series of Bureau publications appraising the Nation's coking-coal reserves by counties and the practicability of upgrading marginal deposits to metallurgical standards. The first publication dealt with the preparation characteristics of the principal coal beds in Cambria County, Pa. Over 95 percent of the coal remaining in Indiana County is in the Upper Freeport, Lower Freeport, and Lower Kittanning beds. Isolated patches of Pittsburgh-bed coal are present, and the Upper Kittanning bed is found in minable thickness at some locations, but production from these sources is not large. The greatest production is from the Freeport beds, which account for nearly 70 percent of the Indiana County coal output. These beds usually contain two or more shale or hone partings and in many places are high in sulfur. The large proportion of bony coal in the Freeport beds 'produces a relatively high-ash product. Mining practices vary from place to place, but it is frequently necessary to leave certain bony portions of the bed in place in order to load a satisfactory product. Table 1 shows the county's coal production, by beds, during 1948.

Jan 1, 1951

By M C. Evans

"Mine decommissioning is the final phase in a mining project. Planning for decommissioning must commence for a proposed mine even before the government approves it. Queensland mining approvals require proponents to commit to completion (or closure) criteria defining successful rehabilitation. Queensland mining project statutory environmental authorities must also specify how progressive rehabilitation is to occur throughout the mining project. Final landforms with graded banks together with creek and run-off diversions are often required and constructed early in the life of a mining project. At closure, mining projects must demonstrate that future medium-term risks are not significant, or failing this, a residual risk financial payment must be made to the state. CSIRO climate change projections indicate that Queensland is likely to become warmer this century with less rainfall in parts and with extreme rainfall events likely to occur more frequently. This project was undertaken to?determine: if current rehabilitation planning tools assist in determining the environmental risks from mining closure not adequately addressing climate change if these risks are addressed by current rehabilitation outcomes.The north-west Queensland mining region and the central Queensland coalfields were represented in this project by five study sites. Local data sets for temperature, rainfall and rainfall intensity were produced using conservative greenhouse gas emission scenarios representing likely future atmospheres, and using the SimCLIM climate model, Evaporation data sets were also derived from available climate parameters. These projected climate variables supported equations and models used in Queensland to determine mining project rehabilitation completion criteria. Storm intensities and return intervals were directly applied to assess the likelihood of failure of engineered structures such as stormwater diversions and banks. Plant cover change determined by an existing growth model together with rainfall intensity and changes in the R and C factors of the universal soil loss equation (USLE) erosion model enabled estimates of long-term erosion rates. Flood estimates were undertaken using regional rated catchments.The study found that stormwater diversions and banks on recontoured rehabilitated landforms, if constructed to currently accepted completion criteria, would likely fail within 30 years and with the likelihood of failure steadily increasing thereafter. The change in likelihood of failure was able to be estimated and could be applied to the determination of residual environmental risk for approval of a surrender application involving rehabilitation. The USLE model showed that long-term erosion rates increased as a consequence of climate change from north to south across the Queensland mining precincts. Because the growth model did not consider carbon dioxide fertilisation affects, results would likely be worse-case.Likely climate change outcomes have consequential residual environmental risks of mining project rehabilitation failure. This increased risk may result in increased payments to the state from mining projects where high consequences exist. The liability to the state and risk to the environment can be avoided if today’s completion criteria address tomorrow’s climate change impacts.CITATION:Evans, M C, 2014. Queensland mines should consider climate change impacts for decommissioning, in Proceedings Life-of-Mine 2014, pp 535–562 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 16, 2014

By D. M. Schubert

As a clean and renewable energy carrier, hydrogen is an important component of most alternative energy portfolios. Hydrogen combines very high energy content by weight with excellent environmental attributes. Since hydrogen reacts with oxygen to produce only water with release of energy, it can be used to power fuel cells, combustion engines, and turbines, without production of greenhouse gases at point of use. However, because of its low volumetric density, storing pure hydrogen is impractical. Thus implementation of hydrogen technologies requires materials that can safely store and release large amounts of hydrogen (1,2). In recent years, the U.S. Department of Energy (DOE) and other governmental agencies around the world sponsored extensive research on hydrogen storage materials, including those based on boron. These efforts have resulted in significant advances in hydrogen storage technologies. Boron materials stand out as leading candidates for hydrogen storage among the many options investigated. Combining excellent hydrogen densities, release rates, and safety characteristics, some boron materials can hold substantially more hydrogen by weight and volume than even pure liquid hydrogen (3-5).

Jan 1, 2010

By Hai Lin, Renshu Yang, Yongliang Li, Shizheng Fang

With the aim of solving the large deformation problem of surrounding rock in coal mine roadways with a thin sand-mudstone interbed roof, transportation roadway 1603 in Haoyuan Mine was considered. The failure mechanism of surrounding rock was studied through comprehensive on-site investigations, borehole image analysis, mineral composition analysis, and other means. Numerical simulations were performed to determine the influence of roof layer thickness, lateral pressure coefficient, and coal rib strength on the stability of the interbedded roof. The main reasons for support failure and deformation of the roadway are softening and swelling of the sand-mudstone interbed roof upon exposure to water, insufficient support capacity of the roof due to the soft coal rib, an unreasonable support scheme, or poor construction quality, which can reduce the bearing capacity of surrounding rock. Based on our analysis, a control strategy was devised for a thin coal-mudstone interbed roof. The support scheme combines long and short cable support, strengthening of the coal rib to consolidate the roof, and partially shotcrete grout, and was found to improve the overall mechanical strength of surrounding rock and maintain the stability of the thin sand-mudstone interbed roof. The results of the numerical simulations and monitoring data indicated that the proposed support scheme effectively controls the deformation of the surrounding rock of thin sand-mudstone interbed roof of coal mine roadways while maintaining the safety and stability of the surrounding rock and supporting structure.

Dec 12, 2022

By J. Bickson, C. DeGennaro, J. Homer, M. Girman

Powered haulage and haul truck-related fatal accidents are among the most frequent at surface mines. Industry organizations developed guidance on accident scenarios to address haul truck and mobile equipment collision-related accidents. However, there is a need to investigate accident data to prioritize these scenarios and identify factors relevant to developing validation methods for collision warning/avoidance technologies and determining their capabilities and limitations. Standards and effective validation methods are necessary for improving system efficacy within mining operations and promoting industry adoption. To address these needs, researchers from the National Institute for Occupational Safety and Health (NIOSH) investigated available powered-haulage and machinery-related fatal accident reports documented by the Mine Safety and Health Administration (MSHA). Their objective was to gain a perspective for informing the development of test protocols and validation methods through determining the most prevalent accident scenarios and related factors. Our findings afford insight for addressing the most prevalent haul truck scenarios and relevant factors within U.S. surface mining environments.

Mar 2, 2022

By J S. J van Deventer

"Conventional wisdom is that gold not assayable is not recoverable or does not exist. There has been no formal study on the possibility that gold assays using advanced spectroscopy such as mass spectrometry and neutron activation could grossly underestimate the gold recoverable by proprietary extraction techniques. Such gold is not considered here to be æinvisibleÆ to detection but rather æabnormalÆ or ædistortedÆ at atomic level. Large-scale extraction of gold from æabnormalÆ ores has not been demonstrated, hence this emerging field still lacks credibility and acceptance. For fear of harming their reputation, few academic researchers or companies are expected to venture into this field until it is well proven. This paper aims to create awareness amongst metallurgists of the potential of æabnormalÆ gold ores by reviewing unconventional observations, the pseudoscience mainly available in non-peer reviewed web sites, and hypotheses for the recovery of ænon-assayableÆ gold, including: the occurrence of high levels of nano-sized gold in clays detectable by high-precision analytical instruments, which represents æinvisibleÆ gold accounts of ambient transmutation of elements, mainly using thermal methods orbitally rearranged monoatomic elements (ORMEs), which are virtually undetectable by conventional means, and their conversion to normal metals the possibility of a æhigh spinÆ state of transition metals the formation of microclusters altering the chemical behaviour of gold and the possibility of clustering with other elements. It is suggested here that gold in ores displays a range of clustering, from ænormalÆ gold amenable to conventional extraction to the ORME state. The concepts of æintermolecular waterÆ in forming complex salts locking up precious metals, electro-dissolution in strong acids, and electrowinning at both the anode and cathode are discussed as a means of treating æabnormalÆ gold ores. It is also possible that the gas phase extraction of gold chlorides under controlled temperature and pressure conditions, as well as transferred-arc plasma fuming of gold through carbothermic reduction of sulfides, could be used as a basis for extraction of gold from æabnormalÆ ores.CITATION:van Deventer, J S J, 2013. Is there gold that we do not recognise?, in Proceedings World Gold 2013, pp 27-34 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Sep 26, 2013

By A. N. Baldwin

This report documents the work performed under Bureau of Mines Contract J0265029 to study and develop two innovative mining systems: ? An underground auger capable of augering into the right and left ribs without repositioning the machine ? A conventional mining system employing recently developed innovative machinery. The report is separated into two volumes to document the two studies separately. Volume I describes work performed and the recommended concept for a bidirectional auger. Volume II describes the studies of mining equipment performance and mining plans developed to determine a conventional mining plan offering improved productivity.

Jan 1, 1977

By Will H. Coghill, I. L. Feld, G. D. Coe

The object of this paper . is to make known the superior classification accomplished in a hydraulic classifier designed to make use of principles determined by recent research ... The details of the design , the results of preliminary research , and the final testing are given . The classifier of the new design shown in figure 1 and another one like it are in operation as concentration classifiers in a Birmingham iron- ore mill recovering 4 tons per hour of concentrates from table middling that ` otherwise would require regrinding and retabling . The four factors that contribute to the successful operation of these classifiers are ( 1 ) a teeter column of small diameter , ( 2 ) use of an open - bottom tooter column classifier with a periodic pincer instead of the usual type , which terminates in a vortex, ( 3 ) a sorting chamber under separate hydraulic control , and ( 4 ) a teeter column of more than the usual depth . · At the outset it must be stated positively what the authors mean by hydraulic classification : They mean the reconstruction of a multimineral ground product into fractions graded with respect to size , so that cach fraction has the heavy mineral segregated in the fine sizes and the light mineral segregated in the coarse sizes . This definition presupposes that in multiplespigot classification the low specific gravity minerals are carried beyond the first cells to the later ones . The reader must take into account that , from the standpoint of classification , " ores " may be divided into two types , represented - by the following : ( 1 ) Joplin flint - blende ores , which , because of the hardness of the flint and the softness of the blonde , yield upon comminution a product that already has the essence of classification ; and ( 2 ) Birmingham Big Seam iron oros , which contain " easily shelled - out " sca sand and , upon reduction to about 10 mesh , yield a heterogeneous mixture in which the size analyses of the respective " floats " and " sinks " arc almost identical .

Dec 1, 1945

By Brendan Donnelly, Lasitha Piyathilaka, Jung‑Hoon Sul, Sanghyun Jeong, Benjamin Probyn

Premature failure of armoured face conveyor (AFC) chains due to corrosion is a significant proportion of the unplanned downtime experienced on longwall equipment. The AFC chains are constantly in contact with water and wet coal. The premature failure issue of AFC chains has become more prominent since the introduction of longwall top-coal caving with its additional AFC. Reverse osmosis (RO) is a popular water treatment method for reducing salinity and dissolved solids, but its impact on the corrosion of the AFC chains is unclear. This study has been commissioned to investigate the direct effects of RO water on the corrosion of AFC chains. An immersion test was carried out using AFC chain steel submerged in two water samples: untreated dam water and treated water from an RO treatment plant. Elemental analysis was conducted for both water samples, and four corrosion indices were measured for both water samples. The RO water more vigorously dissolves calcium carbonate scales leading to increased corrosion of the AFC chains although the dam water has much higher levels of calcium, chloride, sulphate, sodium, and magnesium. Bicarbonate ions are the main alkaline factor of water that provides the buffering capacity to acids. Decreased alkalinity without balancing other ions in water causes high corrosivity and decreased scaling tendencies.

Oct 16, 2023

By Jon Pocock, Ashma Singh

The traditional approach for the beneficiation of South African siliceous sedimentary phosphate ores has been reverse cationic flotation. The robustness of this approach, however, has been a concern due to its sensitivity to parameters such as slimes content, headgrade ( P2O5 and SiO2 content), reagent dosages and conditioning times. The phosphate mineralisation for the ore body under investigation is predominantly carbonate fluorapatite composed of mainly quartz and apatite and minor amounts of chlorite, ilmenite and carbonates. Beneficiation of low grade sedimentary ores containing calcareous impurities, such as calcite and/or dolomite in addition to siliceous gangue, is required to meet the increasing demand; therefore, much research has been carried out to find an alternative technique to beneficiate this material. This paper investigates traditional flotation approaches versus the currently adopted ‘Crago Process’. Comparative results are presented in terms of upgrade potential for the production of concentrate rock for downstream applications. The novelty of the ‘Crago Process’ lies in its double stage approach, i.e. direct fatty acid flotation followed by reverse cationic amine flotation. The Crago process was able to achieve higher upgrades reporting at 32.1% P2O5 compared to conventional cationic flotation only achieving grades of 18.5% P2O5. Furthermore, the recovery gain was 3%.

May 13, 2023

By Robert B. Parsons

"Finance Minister Paul Martin's second budget might be good for Canada's mining industry in the long run, but the budget raises a number of concerns for the industry in the near term. The budget papers suggest that the 25% resource allowance is not working as intended, and report that the Department of Finance will be reviewing this valuable allowance. The so-called ""large corporations tax"" rate will be increased. This annual tax, which is imposed on a corporation's capital even when the corporation is not in production, is particularly harmful to the mining sector.IntroductionThe Honourable Paul Martin, in his second federal budget, emphasized spending cuts and made only modest tax changes. However, two of these tax changes could have a serious impact on the Canadian mining industry: the proposed review of the 25% resource allowance; and, the increase in the large corporations tax rate.Personal Tax Measures Personal Tax Rates UnchangedThe government has been under political pressure not to increase personal tax rates. Mr. Martin's announcement that rates would not change will be popular."

Jan 1, 1995

By D. Harrington

This circular is part II of a series of papers reviewing the literature on air conditioning in mines with particular reference to the health, safety, and efficiency of employees. It deals with the physiological aspects of the principal physical qualities of mine air; part I (Information Circular 7001), chapters 1 to 3, discussed the physiological aspects of the chemical qualities of mine air, especially when contaminated with organic matter and noxious and toxic gases; part III will describe theoretical and practical methods of air-conditioning mines to try to correct or alleviate the conditions mentioned and will discuss the results attained by some of the systems now in use in various parts of tae world. With the present emphasis on the necessity for preserving the health of the Nation's defenders, industrial as well as military, attention should be called to the various conditions that may affect adversely their health and efficiency. One of the most important of these is exposure to abnormal air conditions, especially high temperatures and humidities. Therefore, it is believed that although the data presented here on the physiological effects of exposure to high temperatures cue intended mainly for the mining and allied industries, they are applicable to many other defense industries as well as to conditions present in some activities of the Army and Navy.

Jan 1, 1941

By D. Kong, A. Klyashtorin, L. McGilp, I. Wilson

This work reports on applying iron oxide coated sands media in an experimental permeable reactive barrier to remove uranium species from uranium containing water. A field experiment was conducted at the legacy Gunnar uranium mine & mill site that was abandoned in the 1960s with limited to no decommissioning. The flooded Gunnar mine pit presently contains about 3.2 million m3 of water contaminated by dissolved U (1.2 mg/l), Ra-226 (0.4 Bq/l), and minor concentrations of other contaminants (As, Se, etc.). The water is seeping over the pit rim into Lake Athabasca posing environmental and health concerns. Iron oxide coated sands can be used to immobilize uranium species through an adsorption process. Methods for preparation of hydrous ferric oxide sorbents and their supported forms onto silica sands are described. Fourier transform infrared spectroscopy (FTIR), and powder X-ray diffraction (pXRD) were used to characterize the physical-chemical properties of the sorbent. The monolayer uranium uptake capacity (Qm) was estimated through the Langmuir adsorption isotherm. Adsorption kinetic experiments were performed in a lab environment before moving to a field trial. Based on these lab results and the input on field-scale appropriate geometries, a pilot permeable reactive barrier was fabricated and a field test conducted near the Gunnar pit in June 2019. This pilot test provided technical data and information needed for designing a full-scale permeable barrier based on the iron oxide coated sands, which may be applied for in-situ water treatment at Gunnar and other legacy uranium sites.

Jan 1, 2020

By Rudrajit Mitra, Erik Hulthén, TOBIAS HARTMANN, ELISABETH CLAUSEN, Aarti Sörensen

There has been an ongoing debate on how to transform engineering education to better prepare students for today`s professional world that is characterized by increasingly complex problems and challenges that engineers are tasked with upon entering the industry. Within the conceive–design–implement–operate (CDIO) framework, entrepreneurship education presents a valuable pedagogical approach to foster the necessary skills of the students through integrated, hands-on, active learning experiences. While numerous publications have addressed possibilities of how experiential, problem-based, project-based and active learning can be integrated into engineering curriculum, there has been hardly any attention on mining engineering with respect to adopting this approach. This paper will address the possibilities of integrating entrepreneurship education into mining engineering programs in particular. This paper will enhance and foster discussion among academics from mining engineering on how to integrate elements of entrepreneurship education on a course, program and departmental level to infuse value creation experiences across the curriculum.

May 25, 2022

By Lewis Robert M.

The importance of phosphate in feeding the people of the world has been recognized by mining companies as they continue their search for new ore deposits and ways of improving phosphate production. An extensive phosphate-recovery research project involving investigation of beneficiation variables by batch testing, flotation pilot-plant processing of the major portion of the ore, gravity separation of the coarse fraction, and recovery of byproduct heavy minerals of a North Carolina phosphate deposit has been completed. Data obtained through batch tests enabled the development of an economical flowsheet which proved successful for the efficient recovery of a good quality phosphate concentrate in a pilot plant.

Jan 1, 1975

By F. H. Gunnell, W. C. Dunham

"INTRODUCTION The Treasure Hill mines, situated in Dry Canyon, Ophir mining district, Tooele County, Utah, together with several other properties in the district, examined were examined by Frank L. Wideman, an engineer, the Bureau of Mines, in September 1942.In April 1945, development drilling was started on the Treasure Hill mines, which are operated under lease from the Madison Mines Co. The project was continued in 1946 and terminated in 1947.While the Bureau of Mines project was in progress, the Morgan and Fullion tunnel workings were surveyed by Bureau engineers.ACKNOWKEDGEMENTSIn its program of investigation of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy, It is the policy of the Bureau to publish the facts developed by each project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual investigative perk, and prepares the final report. The Branch, O. C. Ralston, chief, analyzes samples and performs beneficiation tests. The work here described was under the direct supervision of Paul T. Allsman, chief, Salt Lake City Division, Mining Branch."

Jan 1, 1948