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By Douglas R. Simms

O & G Industries, Inc. owns and operates a number of rock quarries within the State of Connecticut. These rock quarries are surrounded by residences and commercial neighbors who have concerns related to blasting. In addition, local commissions which issue the mining permits to O & G are required to hold public hearings, prior to issuing the annual permits each year.

Jan 1, 1994

By C. Van Dyke, K. Van Dyke, J. Gutierrez, C. Nowack

"Using propidium assay and flow cytometry, we examined how silica exerts its toxicity toward phagocytic cells employing the human neutrophil as a model. This toxicity appears to be associated with calcium bound to silica. Once the silica with calcium is phagocytized, the extra calcium causes the death of the cell. Using ""Ca we found that 6 to 10% of millimolar calcium is bound to milligram amounts of respirable-sized silica (diameter of 5 µ.m or less) at physiological pH. If the silica particles arc coated with an organosilanc (Prosil 28). calcium binding is decreased by 60% as is cell death. Pretreating with INDO IAM (a chelator of intracellular calcium) reduces the cellular death by 80%. Nonfibrogcnic particles- polystyrene beads or coal dust-produced 10% or less cell death in a 4-h period. Silica with no added, external calcium appears to exert toxicity to neutrophils; however, pretreating cells with EDT A decreases cellular death to the level of nonfibrogcnic particles. Chronic toxicity with silica-calcium appears similar to the chronic toxicity in gout where particles cause a cycle of inflammation. c 1993 Academic Press, Inc.Silicosis is an occupational disease caused by the inhalation of fine particles of silica, usually between 0.1 and 5 µ.m in diameter (1). A recent hypothesis explaining silica's toxicity suggested that surface free radicals caused damage to cells (2). This explanation appears doubtful, however, since the addition of silica to water, such as that found in biological systems, quenches free radicals; also, such a hypothesis does not provide basis for a persistent inflammatory pattern that lasts for years. Kane et al. (3) proposed that silica's toxicity resulted from an excessive concentration of calcium ions within the phagocytic cell (macrophages). However, the mechanism that was capable of linking silica to an excess of intracellular, ionic calcium was not explained. The surface of silica is certainly involved because covering the surface with polymers or phospholipids decreases silica's toxicity (4-6).When silica is engulfed by macrophages platelet activating factor and leukotrienes are produced (7, 8). This is the same inflammatory pattern produced by phagocytic cells exposed to the calcium ionophore A23187 and ionic calcium. How could silica be acting like A23187? Perhaps calcium binds to silica extracellulary and then is released intracellulary following phagocytosis; the latter process, in a sense a ""piggy back"" process, would permit activation of inflammation and cell death mechanisms."

Nov 1, 1995

By J. H. Schloen

"One of the most important phases in Canada's relatively rapid development of its metal mining and refining industries was launched in 1928 when the directors of Noranda Mines Limited decided to establish an electrolytic copper refinery ""somewhere in Eastern Canada”. Noranda's president, J.Y. Murdoch, had already evolved the company's ""mine to market"" policy and was determined to prove the economic feasibility of refining Noranda copper in Canada. The time appeared to be ripe as buoyant business conditions continued into 1929. In addition, proven ore reserves at the Horne Mine in northwest Quebec had virtually tripled and the price of copper had reached a healthy 15 cents per pound. Letters Patent incorporating the company bearing the date February 6, 1929 had been granted by the Secretary of State in accordance with an application that specified a capital structure of $2 million divided into 20 000 shares with a value of $100 each. Noranda assumed 70% of the original investment in the proposed refinery, while the Nicholas Copper Company of New York (which later became Phelps Dodge Corporation) and British Metal Corporation Ltd. of London, England, each were responsible for 15%. Nicholas Copper Company agreed to supply the design and to supervise the construction of the refinery and British Metal Corporation would act as sales agent and market the refinery's products."

Jan 1, 1999

By James K. A. Harral

The growing national concern over energy has aroused a great deal of interest in the most efficient and least costly way to use our remaining fossil fuel reserves. A number of studies have been published which compare the overall thermal efficiency and cost of gas and electric energy. These studies have been carried out by a wide variety of organizations including Oak Ridge National Laboratory, The Rand Corporation, The Stanford Research Institute, and The Institute of Gas Technology. This paper is an attempt, by PGandE, a large combined gas and electric utility serving most of the northern and parts of central California, to compare the cost and efficiency of gas and electric energy for certain residential appliances using actual operating data and financial statistics for the year 1974, and thereby develop some guidelines for future energy developments utilizing these limited fossil resources. The appliances chosen for the study were kitchen ranges, clothes dryers, hot water and space heaters. These appliances were selected because they can be served with either gas or electricity and they account for approximately one-third of PGandE's total residential electric sales and nearly all of PGandE's residential gas sales.

Jan 1, 1976

By J Li, A McFarlane, J Yu, L L. Kuhar, R Meakin, N Chapman

"Column leach tests are used frequently to predict recoveries and reagent consumption for nickel laterite heap leaches. These column leaches often run for more than 100 days and therefore require long-term monitoring and data analysis to achieve the desired information. To minimise the cost and time required to obtain relevant information for nickel laterite heap leaching, we have developed a small-scale hydrogeometallurgical laboratory test to serve as a proxy to column, and by inference, heap leaching. In excess of 50 leach tests were conducted using four different small-scale proxy and column leach tests to compare predicted nickel recoveries, acid consumption and leach kinetics and to determine whether insight into potential scale-up effects can be obtained. The most promising proxy test was identified and we achieved a statistically significant recovery and acid consumption correlations between this test and the column leach tests. The accuracy of the small-scale tests was confirmed by column tests run on new laterite ores. This geometallurgical proxy could be of use for the population of block models and process selection during the mine planning phase or for optimisation and control during processing.CITATION:Li, J, Kuhar, L L, Meakin, R, Chapman, N, McFarlane, A and Yu, J, 2016. A Geometallurgical Proxy for Nickel Laterite Heap Leaching, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 335–340 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

By James H. Boettcher

Inflation and increasingly complex tax laws in the United States combined with rising national ism overseas have made the structuring of viable financing plans which meet the requirements of the various parties involved equally important in determining project success as the design of an efficient mining plan or selection of the optimal size equipment. Whereas the use of computerized analysis to design and evaluate the technical parameters of resource ventures is well accepted, computerized evaluation of the investment criteria (qualitative and quantitative) of the various parties to the project (mining firm, financial institution, product buyer, host government, etc.) is a more recent application which can make a material impact in strengthening project economics. By identifying the objectives of the parties and critically evaluating and testing them with the technical and economic/financial constraints on the project the sponsors can design a financial structure tailored to the attributes of the deposit. A myriad of new financial techniques have evolved for financing natural resource ventures, from "Commodity-backed bonds" to tax based limited partner- ships, but in every case the structure of the financing mechanism depends on carefully matching the parameters of the financial structure with the economic characteristics of the project and the objectives of its sponsors. This presentation outlines a methodlogy for computer based project evaluation in the design and structuring of stronger financial plans for natural resource ventures.

Jan 1, 1982

By Frederick W. Breaks, Andrew G. Tindle, Julie B. Selway

"Abstract - Rare-element pegmatites may host several economic commodities, such as tantalum (Taoxide minerals), tin (cassiterite), lithium (ceramic-grade spodumene and petalite), and cesium (pollucite). Key geological features that are common to pegmatites in the Superior province of Ontario and Manitoba, Canada, and in other large tantalum deposits worldwide, can be used in exploration.An exploration project for rare-element pegmatites should begin with an examination of a regional geology map. Rare-element pegmatites occur along large regional-scale faults in greenschist and amphibolite facies metamorphic terranes. They are typically hosted by mafic metavolcanic or metasedimentary rocks, and are located near peraluminous granite plutons (A/CNK > 1.0). Once a peraluminous granite pluton has been identified, then the next step is to determine if the pluton is barren or fertile. Fertile granites have elevated rare element contents, Mg/Li ratio < 10, and Nb/Ta ratio < 8. They commonly contain blocky K-feldspar and green muscovite. Key fractionation indicators can be plotted on a map of the fertile granite pluton to determine the fractionation direction: presence of tourmaline, beryl, and ferrocolumbite; Mn content in garnet; Rb content in bulk K-feldspar; and Mg/Li and Nb/Ta ratios in bulk granite samples. Pegmatite dikes with the most economic potential for Li-Cs-Ta deposits occur the greatest distance (up to 10 km) from the parent granite.Metasomatized host rocks are an indication of a nearby rare-element pegmatite. Metasomatic aureoles can be identified by their geochemistry: elevated Li, Rb, Cs, B, and F contents; and by their mineralogy: presence of tourmaline, (Rb, Cs)-enriched biotite, holmquistite, muscovite, and rarely garnet.Once a pegmatite dike has been located, the next step is to assess its potential to contain Ta mineralization. Pegmatites with the highest degree of fractionation (and thus the most economic potential for Li-Cs-Ta) contain blocky K-feldspar with >3,000 ppm Rb, K/Rb < 30, and >100 ppm Cs; and coarsegrained green muscovite with >2,000 ppm Li, >10,000 ppm Rb, >500 ppm Cs, and >65 ppm Ta. Pegmatites with Ta mineralization usually contain Li-rich minerals (e.g., spodumene, petalite, lepidolite, elbaite, amblygonite, and lithiophilite) and may contain Cs-rich minerals (e.g., pollucite, Cs-rich beryl). The ore minerals of Ta are commonly manganotantalite, manganocolumbite, wodginite, and microlite; Ta-rich cassiterite is also commonly present. Tantalum mineralization tends to occur in albitic aplite, mica-rich (lepidolite, cleavelandite ± lepidolite), and spodumene/petalite pegmatite zones."

Jan 1, 2005

By D. R. Dolinar, J. Pablic, D. C. Oyler, T. P. Mucho

At a mine in central PA, high horizontal stresses have caused long running roof falls resulting in hazardous conditions for the miners and the premature abandonment of panels. Because of these conditions, the mine requested assistance of the National Institute for Occupational Safety and Health (NIOSH) in utilizing the "advance and relieve" method to mitigate the affects of horizontal stress on the mine roof. "Advance and relieve" mining involves the removal of a pillar or a portion of a pillar during development, thereby creating a cave along one side of the panel. Following cave development, the horizontal stress is relieved over the workings adjacent to the cave in the active panel. The mine has used this system in three panels with a significant reduction in stress damage and no large roof falls.

Jan 1, 2001

By D. R. Dolinar, J. Pablic, D. C. Oyler, T. P. Mucho

At a mine in central PA, high horizontal stresses have caused long running roof falls resulting in hazardous conditions for the miners and the premature abandonment of panels. Because of these conditions, the mine requested assistance of the National Institute for Occupational Safety and Health (NIOSH) in utilizing the &apos;advance and relieve method to mitigate the affects of horizontal stress on the mine roof. "Advance and relieve" mining involves the removal of a pillar or a portion of a pillar during development, thereby creating a cave along one side of the panel. Following cave development, the horizontal stress is relieved over the workings adjacent to the cave in the active panel. The mine has used this system in three panels with a significant reduction in stress damage and no large roof falls.

By D. R. Dollnar

At a mine in central PA, high horizontal stresses have caused long running roof falls resulting in hazardous conditions for the miners and the premature abandonment of panels. Because of these conditions, the mine requested assistance of the National Institute for Occupational Safety and Health (NIOSH) in utilizing the &apos;advance and relieve method to mitigate the affects of horizontal stress on the mine roof. "Advance and relieve" mining involves the removal of a pillar or a portion of a pillar during development, thereby creating a cave along one side of the panel. Following cave development, the horizontal stress is relieved over the workings adjacent to the cave in the active panel. The mine has used this system in three panels with a significant reduction in stress damage and no large roof falls.

Jan 1, 2002

By Jeff Bird, Xijia Wu, Prakash C. Patnaik

"Prognosis and health management (PHM) is an evolving suite of technologies intended for application to the life cycle management (LCM) of mission/safety critical systems, with anticipated results, which will: - Reduce life cycle cost - Enhance operational safety and readiness - Assist in maintenance decision-making - Enable autonomic logistics While it is emphasized in the United States that future multi-mission fighter aircraft such as Joint Strike Fighter (JSF) must have PHM capabilities, Canadian initiatives also recognize the need to implement such schemes for future and legacy military and civil aerospace systems. With respect to four major technology areas of PHM, i.e., i) advanced sensors, ii) data analysis and fusion, iii) life consumption evaluation, and iv) predictions with reliability/risk assessment, there has been advanced technologies developed by NRC and others within Canada: - Aircraft/engine instrumentation and airborne data recording systems - Signal analysis and data fusion - On-line engine health monitoring - Physics based models for engine material failure modes and life prediction - Autonomic crack growth analysis for damage tolerance of engine components - Mission severity analysis algorithm - Probability, reliability and risk assessment This presentation reviews the above technologies in relevance to PHM, emphasizes the need to have physics based models and outlines the future R&D needs for integration and implementation of these technologies suitable for the advanced and legacy aircraft."

Jan 1, 2004

By James R. Jones

The tempo of air pollution control regulations has increased dramatically in the past few years. Because coal mining operations are frequently located in remote areas away from urban developments, specific regulations applying to coal mines have received lower priority and are thus only now being promulgated and/or enforced. Therefore, many mine operators are not yet familiar with the regulations and the impact upon their method of operations. Few have been faced with an inspector on the property sighting them for specific violations. Several of the Mid-western states are just now requiring permit applications to be submitted.

Jan 1, 1973

By R. Carrier

"There has been a continuous evolution with the use of pre-cast concrete elements in the construction of aluminum smelters. In 1990, Phase I of Alouette was built using cast-in-place concrete exclusively. Whereas, other AP 30 technology plants such as Hillside 2 in the mid-1990s used pre-cast concrete beams with cast-in-place floors. Mozal 2, in 2002, used pre-cast concrete beams with pre-cast partial-slab operating floors. Alouette Phase II went further. Not only were the potroom building beams and floors pre-cast, but the entire pot support system, insulating walls and basement jersey walls were pre-cast. Once the techniques for bending and welding the reinforcement bars and the design for attaching electrical insulating plates to the concrete was perfected, the challenge for the project remained only in the logistics of transporting the pieces to site and simple erection. The overall impact on the project was dramatic. Using prefabricated concrete not only allowed advancement of the schedule, but totally eliminated formwork, re-bar installation, and form removal activities along with the handling of all the materials involved with these activities. With the elimination of these labour and material-intensive portions of the job, exposure to work injuries was dramatically reduced. The most prevalent activity for lost time accidents is during the rough work associated with concrete formwork, placing concrete and form removal. Another area where prefabricated elements were successfully used on Alouette Phase II was for the insulating walls enclosing the pot area, known as the ""claustra walls"". Usually these walls are constructed in-situ using mortar and breeze block. Success was also achieved with prefabrication of the perimetric walls that are installed at the lower floor of the potroom. A big advantage of using prefabricated concrete in the electrolysis area is in assuring electrical isolation for the operating floors. Poured concrete requires a meticulous clean-up effort before commissioning to establish the electrically ""floating"" characteristics of the operating floors. Poured concrete results in ""wash"", stray wood,"

Jan 1, 2006

By B Tutmez

Determination of stress-strain behaviour of rocks plays a crucial role in understanding the response of rocks during loading. However, it is a tedious, expensive and a time-consuming process to obtain such characteristics both in the laboratory and in situ. On the other hand, non-destructive testing methods such as ultrasonic velocities can produce a reliable and fast solution to indentify state of strain and stress in rocks. The present paper aims to provide insight into the relations amongst ultrasonic wave velocities, amplitudes and deformability properties of porous siltstone under compressive loading. For this purpose, pulse (vP) and shear wave velocities (vS) along with amplitudes (AP - AS), and applied loads with resultant strain were measured simultaneously so that response of siltstone to compression can be evaluated. In addition, initial vP and vS were recorded at the beginning of each test to calculate dynamic elastic properties of the specimens. This provided a comparison between static and dynamic elasticity properties of siltstone. Crack damage associated with the onset of dilation was also investigated. The results showed that there is a non-linear logarithmic relation between velocities and stress-strain level for siltstones.

Sep 26, 2011

BLASPA is the name for a computer code which can assist in the rapid optimisation of blasting procedures in an open-pit mine. BLASPA is based on a mathematical model of the blasting process, a model which has been developing since 1963 as a result of blasting research carried out at the College Militaire Royal de Saint-Jean under sponsorship of the Defence Research Board, and in co-operation with the mining and explosives industry. The model presently includes the following aspects: (1) Geometry, i.e. spacing, burden, bench height, collar, sub-grade drilling; (2) Explosives, i.e. types and grades of explosives, distribution into bottom and top load or decking, size of hole and coupling; (3) Hookup, i.e. parallel or angled firing, delays, location of primers. Computer costs are very small, by comparison with purely spherical AEC codes, so that any number of simulations can be carried out very efficiently. The system has already been used to carry out thousands of simulations for over 40 mines in Canada and abroad. It will be explained how such simulations become a useful guide for a mine's blasting engineer who wishes to optimize his blasting and drilling costs.

Jan 1, 1980

By Robert Hopler

In part one we discussed a Chinese seismoscope allegedly invented and used in the year 136 (or 132, depending on the source). Interestingly, historical references to the measurement of earth movements then seem to be nonexistent until up into the 1700’s. There could be two explanations for this hiatus: first, that there were no earthquakes in the world for 1600 years, or, second, the “Dark Ages” really did exist, where intellectual inquiry and all sorts of learning came to a halt. Of course there were earthquakes, so the explanation for the lack of a record of invention is the reality of the Dark Ages. explained is the fact that the Dark Ages ended in about A.D. 1000, but that is beyond the scope of this story.

Jan 1, 2006

By M. Kellner

Due to continuously growing resource demands and increasing requirements for sustainability, safety and environmental protection on the other hand, the mining industry is being subjected to these additional requirements. Over the past few decades progress has been made in all topics. In 1987, the United Nations published the following in the Brundtland Report: ?development that meets the needs of the present without compromising the ability of future generations to meet their own needs.?[5] The term ?Blue Mining? means to work sustainably, economically, ecologically, and efficiently while also improving ergonomics, for example by increasing automation. An example of how mining can actively be involved in energy management will be shown. Initial evaluations of underground cavitites were done for purpose of energy storage. The planning and construction of underground pump storage plants both in active and inactive mining operations was also investigated.

Aug 1, 2013

By Geo. A. Brown

This paper was written from conditions existing in the Cumberland Mines of The Union Pacific Coal Co., with my impressions and cause of same. These mines are located on a branch line of the 0. S. L. R. R., about sixteen miles south of Kemmerer, Wyoming. The mines are the property of The Union Pacific Coal Company with headquarters at Rock Springs, Wyo. There are two mines, No. 1 and No. 2, located about two miles apart in a seam of coal averaging about 16 feet thick which is split with a parting of rock from 4 feet to G feet from the bottom, averaging from 4 inches to 5 feet thick, mostly of soft fire clay, with an average pitch of 21 degrees to the west. The lower coal below the fire clay band being of a soft nature, much softer than the coal above it. The cover or roof next to the coal is of a massive sandstone formation from 4 feet to 60 feet thick while the floor of the seam is of a soft fire clay as far down as has been prospected. These mines are also of a dry and dusty nature, they generate lots of fire damp and are subject to fires from numerous causes. These mines were opened up in 1900 with five openings each, Main Slope, North and South Manways and North and South Aircourses driven parallel directly on the pitch of the seam which is fairly regular, entries being turned North and South at right angles off the slope about 300 feet apart. The entries were driven double 10 feet wide with chain pillars from 20 feet to 30 feet thick. The main entries are used for haulage and main intake, back entries for return aircourses. Rooms are turned on 50-foot centers and 20 feet wide, directly on the pitch Galvanized sheet iron chutes are used in the rooms. The slopes were driven down in No. 1 mine about 4,000 feet, in No. 2 mine about 5,000 feet where the cover would be about 1,400 feet in No. 1 mine and about 1,700 feet in No. 2 mine approximately. When a point about 2,000 feet on the slope had been reached with cover, 600 or 700 feet squeezing became noticeable on the entries and room pillars with slight bumps which extended clear to the upper entries of the mines and continued to get worse as the mines got deeper and with more cover as no pillars had been removed at this time. It should be stated here that faulty ground was found on the south side of No. 2 mine and on the north side of No. 1 mine, in some places looking like a fault of a down throw, some places like a want and other places like an erosion. The latter theory seems to be correct from prospecting and drilling. The mining of entries and rooms became more difficult with more squeeze and bumps of increased pressure which closed entries and aircourses and finally caused the lower workings of the mine to be abandoned. It was then decided to open up the entries from the 6th up, or approximately half way up the slope. The opening of these entries was started with the intention of extracting pillar coal but considerable danger was met with for the entries .were squeezed tight and when they were disturbed, bumps and squeeze conditions had to be contended with, also gas and fires due to the continued grind on the pillars due to overhead pressure bringing on friction which caused innumerable fires to start in the bottom coal. Bumps being so extensive at times as to close up aircourses for 500 or 600 feet, also discharge timber, coal and rock from the rib of slope and entries for hundreds of feet, dislodging tracks and throwing mine cars around just as if an explosion had taken place, filling places with gas and throwing dust into the atmosphere so that you could cut it with a knife. It became necessary to discontinue the use of black powder and naked lights entirely as a safety precaution. Permissible Powder Monobel No. 5 and Wico Electric Safety Lamps were installed. All coal was shot off the solid whenever it was necessary to shoot. &apos; In opening up these entries it was found that practically all of the weight was centered on room pillars up to the first crosscut chain pillars and barrier pillars between top of rooms of entry below and the one above which averaged 30 feet thick and in all practically 120 feet of ground. The rooms were mostly open from the first crosscut up to the face which showed that the points mentioned had taken the weight. It was found impossible in some of these entries to drive double entries again as the bumps and squeeze made it impossible to maintain them. This made ventilation quite a problem, small booster fans and flexoid tubing being used for ventilation until one entry could be connected with the one above which has solved most of our ventilation problems so far.

Jan 1, 1924

By Charles G. Zink

Early anthracite "deep mining" methods, production, manpower. underground transportation, labor, safety and reserves are reviewed and compared to the present and to future requirements which must be met in order to economically win the fourteen million tons of untapped reserves and to keep the product competitive in the market place.

Jan 1, 1971

By Lawrence F. Johnsen

In 1989, the Connecticut Department of Transportation authorized the evaluation and design for a reconstructed Route 1 bridge over the Quinnipiac River in the City of New Haven, Connecticut. The project extends from the intersection of Route 1 with East Street, easterly for approximately 3/4 mile to the intersection of Route 1 with Wheeler Street and Stiles Street. The reconstructed roadway will be relatively on-line and widened to provide for four lanes of vehicular traffic and a single-track railway line. The existing bascule bridge and approach spans, which were constructed in 1924, will be replaced by a 270-foot span lift bridge and new approach spans. The lift bridge will have a main lift span weighing approximately 3000 tons, second largest after the Burlington Northern Bridge over the Williamette River in Portland, Oregon. The new bridge will widen the navigation channel to 24 0 feet and provide vertical clearances of 13 feet when closed and 62 feet when open. The project is located in an industrial area. Adjacent properties include retail gasoline sales, auto repair, railroad transport and bulk storage of petroleum. Existing structures include the Yale Boathouse and several retaining walls serving as containment dikes for petroleum storage tanks. The Yale Boathouse, located on the east bank of the river, was constructed in 1909-1910 and is eligible for listing in the National Register of Historic Places.

Jan 1, 1993