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By Malte J. M. Gurgel, Axel Preusse

The planning, construction, and monitoring of underground storage facilities is a key factor in meeting upcoming challenges as part of the energy transition from fossil fuels to renewables. Therefore, the many years of knowledge and expertise in ground control gained from coal mining are highly valuable for new mining and storage operations. For such applications, our previous work examined cavity registration, combining structure from motion and LiDAR through a case study in a former lead ore mine. Building on this, the results of this recent case study are discussed regarding the possible application in sites for nuclear waste disposal in Germany including a view on the situation in the United States. Photogrammetric methods are particularly suitable as part of long-term monitoring, which relies on both precise survey results and a large variety of detailed visualization. In order to gain a better understanding of the resulting application potential for holistic monitoring, both existing repositories sites in Germany and ones yet to be found are examined. This search and selection process for high-level nuclear waste disposal is studied in detail together with rules resulting from the (German) mining law, regulations, and other guidelines. Hereby, key requirements of photogrammetric products like oriented images, point clouds, and three-dimensional (3- D) models are identified for different case studies. The findings on accuracy and integrity of the generated models are not only of interest for future repository sites or underground pumped storage power plants, but also offers various possibilities for underground mining of coal and other commodities.

Jul 1, 2023

By S. A. Shoop, J. J. K. Daemen

Site-specific blast vibration prediction can be more accurate than using a universal prediction equation. Vibrations from 37 blasts were monitored using three seismographs. Data analysis showed that square root, cube root, and site-specific scaling predicted ground motion with equal reliability. Imprecise prediction is caused by geologic and blast variability, particularly, inaccurate delay times. Vibrations at some mines were consistently lower or higher than vibrations predicted from US Bureau of Mines (USBM) equations. Vibration restrictions based on USBM studies could then be too conservative or too lenient. Predominant vibration frequencies were generally less than 50 Hz, but several blasts had significant energy up to 125 Hz. In some cases, energy was concentrated at frequencies corresponding to delay intervals.

Jan 1, 1985

By E. Hughes, D. Akers, D. Stopek

The Upgraded Coal Interest Group (UCIG), focuses on clean, low-cost options for coal-based power generation via pre-combustion, co-firing and reburn options. Its mission is to preserve and expand the economic use of coal for energy. By reducing the fuel costs and environmental impacts of coal-fired power generation, existing units become more cost effective and thus new units utilizing advanced combustion technologies are more likely to be coal-fired. Two great forces are reshaping the power generation industry, the Clean Air Act Amendment and deregulation of generation. The Clean Air Act Amendment is forcing change by making it necessary for power producers to plan for reducing emissions of sulfur and nitrogen oxides and possibly trace elements. At the same time, deregulation of generation is forcing utilities to focus their attention closely on the short term impact of any change on cost of power. Fuel is a utility's largest cost element; maximum fuel flexibility will be a utility's best weapon in an environment of rapid change. In a regulated environment, a utility was limited in how involved he might get into fuel supply, in a purely deregulated environment he need only be guided by the impact on the bottom line. It is clear that these two forces will promote a close look at factors such as coal upgrading which can have an impact on the availability of low sulfur coal or emission of NOX and trace elements.

Jan 1, 2000

By Richard Cole

The Energy Act of 1992 has many users of ac-induction motors eyeing premium-efficiency motors with mixed feelings and perhaps some confusion. When the October 1997deadline arrives for compliance with the1992 standards, the winners will be the environment due to reduced need for more power generating plants and the petroleum economy because of reduced dependency on foreign oil. But what will it mean for industrial users? The most obvious benefit is the potential for smaller electricity bills. Motors account for about 64% of the electricity consumed in the United States, at a yearly cost of $112 billion. Every 1% reduction in motor demand cuts 0.64%, or $716 million, off the industry wide bill. Higher efficiency motors also run cooler. This lightens the load on air-conditioning systems and further reduces plant demand. Lower total demand can lead to lower rates by helping to minimize peak-demand surcharges. As rates increase over time, these savings get bigger.

Jan 1, 1996

By William W. Aljoe

The hydrologic characteristics of two abandoned underground coal mine sites, near Latrobe, PA, and Uniontown, PA, were investigated by the U.S. Bureau of Mines for possible implementation of alkaline injection into the mine pools as a means of abating their acid discharges. The Latrobe site was chosen for a one-time application of alkaline injection to achieve a partial, short-term neutralization of a limited portion of the mine pool. A quantity of alkaline reagent (sodium hydroxide) sufficient for a one-time neutralization of the water in this portion of the pool was added. Although nearly all of the neutralizing reagent had moved away from the injection wells within 6 weeks, no evidence of neutralization was noted at the mine discharge during the study period. This lack of neutralization probably occurred because the injection wells did not intercept a primary flow path through the mine. Criteria for successful application of alkaline injection at this or other sites include (1) positive identification of the primary flow paths through the mine pool and (2) addition of quantities of alkaline reagent sufficient to neutralize the entire volume of the pool along the primary flow path.

Jan 1, 2010

By W. G. Pariseau

"The Crandall Canyon Mine (CCM) is located in the Wasatch coal field in central Utah. Extensive longwall mining at CCM preceded a decision to recover coal left in barrier pillars on each side of a set of main entries extending far into the mine. During mining in March 2007, a major bump occurred that led to cessation of mining in the barrier pillar on the north side of the mains and to the start of mining in the south barrier pillar. Subsequent loss of ground control in August 2007, through coal pillar bursts had tragic consequences with loss of six miners and shortly afterward three rescue team members. A U.S. Mine Safety and Health Administration (MSHA)report describes the events in detail (MSHA, 2008).An important lesson to be learned from CCM is the need to select a computer program suitable for pillar design. Computer programs are engineering tools and selecting the right tool for the job is essential. In this regard, minimum program requirements include capability for computing stress distribution within a pillar and adjacent roof and floor strata. The reason is simple: strength of rock is stress dependent; both vary from point to point in pillars and adjacent strata. Preferably, one should follow the evolution of stress as the mining plan is executed from start to finish to assure safety or to warn of a potentially hazardous situation developing as mining progresses.The approach to the problem posed by barrier pillar mining at CCM is conventional in the sense of applying well known finite element modeling techniques to analysis of a proposed mining plan. The engineering purpose is to evaluate the mining plan with respect to ground control questions including roof, floor and pillar safety. Results of previous two-dimensional finite element analysis indicated pillar safety was by no means assured (MSHA, 2008; Pariseau, 2008; Pariseau, 2011). Geometry of barrier pillar mining is limited in two dimensions for example, crosscuts are not seen in vertical cross sections. While three-dimensional analyses are preferred, even moderately sized regions often lead to very large problem sizes that exceed computer capabilities. However, a recent development in finite element modeling of tabular deposits allows for whole mine analysis in three dimensions. This technique involves a dual node - dual mesh concept. Both have been used separately in much earlier work, but are only now used in combination. It is possible to have an estimation of subsidence at a kilometer scale and details of stress, strain and displacement about barrier pillars, main entries and pillars, and so on at a meter scale (Pariseau, 2014). No compromise involving empirical formulas or similar guess work is required. Indeed, all calculations are based on first principles: physical laws, kinematics, and material laws. Effects of joints and in situ variability or uncertainty in strata properties, elastic moduli and strengths, may be included for greater realism. An important objective of the present study is to assess the role of three-dimensional pillar geometry in arriving at conclusions regarding barrier pillar mining versus two-dimensional results."

Jan 1, 2014

By Samuel Polinsky, Lawrence W. Bierman, Wayne Perkins

[A column float beneficiation plant using 9, 8.5 foot diameter, cells was constructed by the Simplot Company and the Smoky Canyon Facility in the fall of 1986 and has been in operation since May of 1987. The float beneficiation process was developed jointly by the Simplot Company and the Bureau of Mines (Salt Lake City, Utah) which incorporates the Bureau's bubble generator design and chemistry system based around the reverse float technology, (Albany Bureau of Mines, Application of Carbonate-Silica Flotation Techniques to Western Phosphate Materials, Rule, Dallenbach , Larsen, RI8728, 1982) . This chemistry has been modified by Simplot in both patented and unpatented improvements. The objective of the beneficiation process was to reducethe A1203 content in the overall pipeline concentrate by 0.2 wt z. Therefore, a process stream was identified in the mill circuit which provided an opportunity to isolate and treat 1100 tons per day of poor quality phosphate concentrates The process allows recovery of approximately 15% of the mill concentrates, otherwise unsuitable for fertilizer production. The alternative would have been to waste this ore. Wasting would have resulted in considerable ore loss, increased mining costs and required additional products grinding. ]

Jan 1, 1989

By Xiao min Zhou, Yan Xu, Hongzhen Liang, Xiaonan He

"With the increase of shaft excavation depth, the thickness of the shaft lining increases sharply. It is difficult to reduce thickness of lining effectively by improving high-strength concrete performance. The concept of the New Austrian Tunneling Method (NATM) is that surrounding rock plays a certain role in tunnel support. The solution should be to find the correct relationship between shaft lining thickness and rock strength, which is related with the interaction between the surrounding rock and concrete lining. The plane strain mechanics model is introduced to calculate lining thickness. Shaft lining design of Cixi Colliery in China is completed with the mechanics-based method proposed in this study. The lining design is verified through numerical simulation and field monitoring. The simulation results show that the maximum mises stress is located at the inner edge of the shaft lining. The increase of lining thickness cannot effectively reduce concrete grade. The monitoring results indicate that a lining design thickness of 900mm with C60 concrete, is safe and reliable in the shaft over 1000metres.This analytical design method can well be referenced in similar deep shaft projects.INTRODUCTION The New Austrian Tunneling Method (NATM), thought to have helped revolutionize the modern tunneling method, is the most extensive design philosophy and construction principle in today's tunnel engineering. It began to attract attention in the 1960s based on the work of Ladislaus von Rabcewicz, Leopold Müller, and Franz Pacher in Austria[1]. NATM was originally developed for tunneling in depth and in high situ-stress conditions in the Alps. The history of sequential excavation was reviewed, which highlights the progress of tunnel design and construction in Europe after NATM[2]. Structural conditions were introduced into the equilibrium of tunnels in NATM, and the additional force was estimated to stabilize the excavation of the tunnel[3].From the perspective of applied mechanics, there was no accuracy theory to explain the interaction between the tunnel structure and the surrounding ground. Numerical calculation is an effective means to study the basic mechanism of tunnel excavation[4].Based on two-dimensional modeling approaches in the past, such as NATM and other derivatives, a three-dimensional model was studied to"

Jan 1, 2019

By D. J. McParland

This paper will deal with some of the considerations which, were involved in the design and construction of the uranium mills in the Elliot Lake area . These plants, eleven in number, range from 1500 to 6500 tons per day milling capacity. Most references are with respect to the seven plants in the Rio Tinto Group which have a combined milling capacity in excess of 20,000 tons per day. In dealing with such abroad subject as mill design, one has the choice, of covering a few specific problems in great detail, or else attempting to cover many subjects superficially and briefly. In preparing this presentation, an attempt has been made to compromise on these extremes, and to select some interesting illustrations which are of general interest in the field of mill design, and of value to persons concerned with mill design broadly, beyond the field of uranium mills.

Jan 1, 1959

By Brian Wilson, John Scholte, Megan Atkinson

"In November 2004, the residents of the City of Nanaimo, B.C., Canada voted to approve a new conference centre as the centrepiece of a proposed revitalization project for the city’s historic downtown core. The proposal goal was to replace a cluster of derelict buildings with a dynamic and modern complex that would connect existing city facilities to a new conference facility, the Vancouver Island Conference Centre (VICC). The conference centre is expected to create 150 full-time jobs, attract visitors/ delegates from across North America and generate new economic opportunities for local businesses.However, the proposed site posed a number of geotechnical and geoenvironmental challenges. As is often the case with coastal cities, historic growth of the Nanaimo downtown and harbour area was achieved through reclamation of former waterfront areas and inlets. These areas were often infilled with random fills and even wastes, leaving a legacy of variable density heterogeneous fills contaminated with a variety of pollutants. Preliminary assessment of the site indicated a high likelihood of a requirement for deep foundations, a high risk of liquefaction in the event of an earthquake and the presence of both soil and groundwater contamination. Construction would be further complicated by the requirement for two levels of basement parking and the proximity of adjacent buildings and major roadways to the work area.With a limited budget (fixed by the referendum) and timeframe, the city needed a cost-effective solution to proceed with construction. A number of options were considered, but an innovative design using leading-edge Cutter Soil Mixer (CSM) technology best met the geotechnical and budgetary requirements of the site. The CSM approach also addressed the environmental concerns of contaminated soils and groundwater. Golder Associates Innovative Applications (GAIA) Inc., in association with the designers of their parent company Golder Associates Ltd. (Golder), proposed the CSM technology — at the time the first North American application."

Jan 1, 2008

By Fumihiko Sumiya, Kunihisa Katsuyama, Yuji Ogata, Yuji Wada, Yukio Katoh, Yoshikazu Hirosaki

In our previous work, the results of photographic observation using a high speed framing camera showed that the difference between precursor air shock wave velocity and detonation velocity was primary factor for the channel effect. It is assumed that the decreasing precursor air shock wave velocity can prevent the channel effect in charge hole.

Jan 1, 1996

By S. B. Levin

The Bureau of Mines has been investigating deposits of critical and essential minerals in the United States and Alaska since 1939. During the fall of 1942, the Bureau of Mines put down nine diamond-drill holes at the Cape Rosier zinc-copper-lead mine in Hancock County, Maine, that aggregated 2,883 feet of bore. These holes supplemented 13 holes, aggregating. 5,501 feet, put down on the property about 2 years earlier by the St. Joseph Lead Co. Veins of mixed sulfides were intersected in 15 of the holes drilled. Beneficiation tests were made on samples of ore obtained from old dumps. Zinc-copper-lead sulfides occur at the Cape Rosier mine as lenses in a zone of altered agglomerate beneath and between a series of diorite sills. The mineralized zone strikes F. 17° E. and dips southeast. Between July 1881 and September 1883 the mine produced about 10,000 tons of ore reported to have contained 20 percent zinc, 2.8 percent copper, and some lead. The crude ore was hand-sorted, and some. 3,000 tons were reported shipped.

Jan 1, 1948

By Luc Harnois, Gabriel Voicu, Marc Bardoux, Robert Crépeau

"Abstract-Detailed petrographical and geochemical studies have been carried out on the igneous and sedimentary rocks in the Omai area, part of the Paleoproterozoic Barama-Mazaruni greenstone belt, Guyana. The stratigraphic succession at Omai begins with basalts, associated with mafic-ultramafic intrusives and poorly-sorted conglomerates; these are overlain by andesites and quartzfeldspar porphyries, with pelites and tuffaceous sediments at the top. The volcanic-sedimentary succession was intruded by a quartz-monzodioritic stock (Omai stock) and granophyric rhyolite dikes. Several generations of mafic dikes were intruded discontinuously from the Mesoproterozoic to the Permo-Triassic. Volcanic rocks range in composition from subalkaline basalt to high-silica rhyolites, with a gap between 60% to 70% SiO2, which suggests the suite is bimodal. Major, trace, and rare earth element criteria were used to subdivide the rocks into tholeiitic and calc-alkaline types. The tholeiitic rocks are characterized by flat to moderately sloping chondrite-normalized REE patterns. On the basis of immobile trace-element ratios, the tholeiitic mafic rocks from Omai have characteristics of immature intra-oceanic island arcs, or of E-MORB basalts affected by a strong arc signature, as is commonly reported for back-arc basin basalts. The andesites, quartz-feldspar porphyries, rhyolites and quartz monzodioritic stock are calc-alkaline, with strongly sloping REE patterns, enrichments in the large-ion lithophile elements, and depletions in the heavy REE and high-field-strength elements, features which are typical of more mature island-arc settings.At Omai, two types of gold-bearing veins can be distinguished: vein sets (± stockworks) and tension veins, both post-dating the regional metamorphic peak at the level they were emplaced. The relationship between the gold mineralization and its host lithologies does not seem to be genetic. Rather, the emplacement of mineralization was strongly influenced by the rheological contrasts between the intrusive/subvolcanic bodies and the volcanic/sedimentary country rocks. These contrasts helped to focus the regional stress upon the more competent intrusive subvolcanic bodies, resulting in brittle fracturing, and therefore in greatly enhanced permeability to hydrothermal fluids. The Omai gold mineralization can be classified as late tectonic, with its emplacement controlled by the last brittle to brittle-ductile stages of the Trans-Amazonian orogeny."

Jan 1, 1997

By Gabriel Voicu, Harnois Luc, Marc Bardoux, Robert Crépeau

"Detailed petrographical and geochemical studies have been carried out on the igneous and sedimentary rocks in the Omai area, part of the Paleoproterozoic Barama-Mazaruni greenstonebelt, Guyana. The stratigraphic succession at Omai begins with basalts, associated with ma?c-ultrama?c intrusives and poorly-sorted conglomerates; these are overlain by andesites and quartz-feldspar porphyries, with pelites and tuffaceous sediments at the top. The volcanic-sedimentary succession was intruded by a quartz-monzodioritic stock (Omai stock) and granophyric rhyolitedikes. Several generations of ma?c dikes were intruded discontinuously from the Mesoproterozoicto the Permo-Triassic. Volcanic rocks range in composition from subalkaline basalt to high-silicarhyolites, with a gap between 60% to 70% SiO2, which suggests the suite is bimodal. Major, trace, and rare earth element criteria were used to subdivide the rocks into tholeiitic and calc-alkaline types. The tholeiitic rocks are characterized by ?at to moderately sloping chondrite-normalized REE patterns. On the basis of immobile trace-element ratios, the tholeiitic ma?c rocks from Omai have characteristics of immature intra-oceanic island arcs, or of E-MORB basalts affected by a strong arcsignature, as is commonly reported for back-arc basin basalts. The andesites, quartz-feldspar porphyries, rhyolites and quartz monzodioritic stock are calc-alkaline, with strongly sloping REE pat-terns, enrichments in the large-ion lithophile elements, and depletions in the heavy REE and high-?eld-strength elements, features which are typical of more mature island-arc settings.At Omai, two types of gold-bearing veins can be distinguished: vein sets (± stockworks) and tension veins, both post-dating the regional metamorphic peak at the level they were emplaced. The relationship between the gold mineralization and its host lithologies does not seem to be genetic. Rather, the emplacement of mineralization was strongly in?uenced by the rheological contrasts between the intrusive/subvolcanic bodies and the volcanic/sedimentary country rocks. These con-trasts helped to focus the regional stress upon the more competent intrusive subvolcanic bodies,resulting in brittle fracturing, and therefore in greatly enhanced permeability to hydrothermal ?uids.The Omai gold mineralization can be classi?ed as late tectonic, with its emplacement controlled by the last brittle to brittle-ductile stages of the Trans-Amazonian orogeny."

Jan 1, 1997

By Arthur F. Hagner

The titaniferous magnetite deposit at Iron Mountain, Wyoming, is in Precambrian anorthosite. Individual ore bodies are lenses, commonly arranged en echelon, conformable to the platy crystal structure and compositional layering of the anorthosite; a few transect these features at various angles. The ore bodies are on the east flank of the principal anticline in the anorthosite mass. Magnetite and ilmenite, accompanied by spine!, are the ore minerals. The principal gangue minerals are olivine, which was introduced with the ore, and plagioclase, the chief constituent of the anorthosite. The anticlinal region appears to have been a structurally weak zone, and westward-bowing curves of the axis were especially favorable sites for localization of the two largest massive ore bodies. These bodies are synclinal and plunge southeast. The proportion of magnetite-ilmenite to olivine and to anorthosite appears to be related to structural features. Where magnetite-ilmenite is present with olivine, the magnetite-ilmenite is encountered along the most pronounced parts of a fold where anorthite content is highest, whereas olivine is associated principally with more gently folded portions. During granulation and recrystallization of the anorthosite mass, temperature and pressure changes furnished the energy required to release and mobilize iron and other elements that migrated to areas of low pressure, the ore zone. Some iron and magnesium may have combined with silica from partly dissociated plagioclase to form olivine. The ore formed by replacement of anorthosite as indicated by: (1) the marked changes in mineralogy along strike, dip, and plunge of an ore body; (2) the concentration of massive ore in folds and olivine on limbs; ( 3) the halo of low-grade mineralized rock that transects the structure of the anorthosite in the hanging wall; and ( 4) the layering in the large southern ore body, that strikes more easterly than the trend of the body.

Jan 1, 1968

By Gary L. Hundley

The Bureau of Mines has devised and demonstrated an ammoniacal sulfate leach process for recovering nickel and cobalt from low-grade domestic laterites. Solvent extraction of cobalt, one of the process steps, requires the reduction of hexammine complexes of C03+ to C02+ in an ammo-niacal leach solution. Previously, reduction was accomplished using cobalt metal shot in a column. This report presents experimental results and an economic evaluation comparing two alternate techniques with the shot column: (1) an electrolytic reduction cell with an extended surface area cathode and (2) direct electrowinning from purified leach solution using a cell with a fluid bed cathode. The second alternative eliminates the conventional solvent extraction-electrowinning steps. The costs of the three methods, based on the requirements of a pro-posed commercial-sized plant, including all unit operations, were deter-mined by the Bureau's process evaluation group. The operating costs for the shot column, $1.19/kg Co, and for electrolytic reduction, $1.20/kg, are essentially the same, but the cost of direct electrowinning, $3.77/ kg Co, would eliminate this method as a practical alternative. The cap-ital cost of approximately $14.4 million for reduction in a shot column is much higher than the approximately $4.4 million for electroreduction.

Jan 1, 1985

By E H. O Meyer, K van Dyk

Fine powders normally exhibit, to a more or lesser extent, some ability to participate in dust explosions. Zinc dust as used in the extractive metallurgy of zinc, is not known to be a reactive powder in the industry. No evidence could be found in the literature where zinc dust was involved in an explosion or explosive type event. On 3 May 2002 an explosive type incident occurred at Zincor in Springs, South Africa, which led to a fatal accident. Given the history of relative benign behaviour of zinc powders under conditions conducive to dust explosions, it was decided to share the information of this incident with industry in an effort to prevent similar incidents. Therefore, the purpose of this paper is to describe the incident that occurred at Zincor, discuss the major findings, report on corrective actions, as well as publish the results of subsequent tests that were performed to determine the conditions under which zinc powder exhibits explosive characteristics.

Jan 1, 2005

By E. J. Matson

Under the investigation for critical and strategic minerals the Kaiser mine, formerly the Baxter fluorspar property, in northeastern Mineral County, Nev., was explored. The work comprised excavating 32 trenches averaging 90 feet in length, 8 feet in width, and 1 1/2 feet in depth. The trenches were excavated across the strike of the ore body to enable the engineer to spot the diamond-drill holes; 7 such holes were drilled, aggregating 3,276 linear feet. A total of 20 core samples and 107 sludge samples was taken. The work under this program indicated that the fluorspar southwest of the deposit extended laterally and also at depth at least 250 feet below the 400-foot level. INTRODUCTION The Kaiser fluorspar deposit is in the northeastern portion of Mineral County, Nev. Mining was begun about 1928, and the property has been a consistent producer of both Acid- and Metallurgical-grade fluorspar. The mineralized zone has been developed along a strike length of about 2,000 feet and to a depth of over 700 feet along the dip.

Jan 1, 1957

By Francisco Herrera R.

El presente texto describe las técnicas de tratamiento en los bancos de datos y sistemas de información de la geología y minería en el Perú. En esta perspectiva, se muestra la organización del sistema de documentación de la bibliografia documentada en el ámbito geológico y minero a través de diversas estructuras, cuya finalidad es generarle al usuario, la facilidad en la búsqueda de información, así como el filtro de la documentación a utilizar.

Oct 14, 1980

By Julio C. Martinez, Jeffrey L. Rice, Hayden Weschler

This paper details the extensive underpinning required to hold up the 39th street Bridge while demolishing its massive support piers and building a 30ft deep Cut/ Cover RR tunnel beneath it. The underpinning/SOE support required the construction of 16 large hand dug pits 36ft deep that were reinforced and concrete filled. In addition, an extensive steel support system was tied into the bridge super structure. All of the underpinning/tunnel construction was done while a 110ton crane sat directly atop the heavily trafficked – 66 ft. wide bridge. The tunnel excavation, concrete lining and final bridge pier support work will also be presented. All work was done within 5ft of active mainline tracks and that required tight grouting behind all lagging to eliminate any track settlement.

Jun 13, 2021