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By Charles Meyer

The year 1955 was a busy one for mining geologists, for the expanding world-wide business activity kept the demand for mining products generally high, stimulating operators to develop local ore reserves and to expand their efforts to find new deposits. The uranium rush was still on, although probably past its maximum rate of climb. Prospecting was also stimulated by the increasing demand for rare metals, and this created new and fascinating targets for exploration. On the whole, it was a boom year when the prospector's chronic optimism found few repressions.

Feb 1, 1956

By T. Krumins, L. Zunti, R. Frischmuth

"Titanium and titanium alloys are commonly selected for pressure oxidation autoclave vent piping and pressure control valve components, as well as autoclave internals and other process piping. In the autoclave vent application, titanium ignition risk is controlled by limiting oxygen concentration, and preventing high gas velocity gas impingement on surfaces. Oxygen concentration is dependent on the autoclave pressure and temperature operating conditions and therefore oxygen concentration and the associated titanium ignition risk is dependent on standard operating procedures, process control interlocks and permissive conditions. It is not uncommon for these standard controls to be deficient during atypical operating conditions, or for operations to deviate from the operating procedures, increasing the potential for a titanium ignition incident. Titanium ignition risk caused by elevated oxygen concentration in autoclave vent systems can be reduced with the introduction of an online autoclave overpressure calculation and the configuration of associated interlocks and permissive conditions. INTRODUCTION High temperature pressure oxidation (>190°C) is a well recognized and versatile metallurgical oxidative pre-treatment process commonly used to liberate gold from refractory sulphide ores and concentrates before conventional leaching with cyanide. Titanium and titanium alloys are highly corrosion resistant in pressure oxidation process conditions and are therefore commonly selected as materials of construction for many components including: autoclave internals, agitators, process piping, and components in autoclave vent systems. Operations that anticipate or have experienced aggressive corrosion in the vent system often have little choice in material selection other than the use of titanium (Krag & Henson, 1992). Titanium is not suitable for use with elevated oxygen concentrations and is considered a restricted material because of its high pyrophoricity and combustion propagation properties (Beeson, Smith, Stewart, 2007). Several serious incidents have occurred in which titanium materials have ignited in autoclave applications (Zawierucha, McIllroy, Million, 1995). In autoclave vent applications, titanium ignition risk is reduced by preventing elevated oxygen concentrations, maintaining low gas velocities, and minimizing the potential for gas impingement on surfaces. Oxygen concentration in the autoclave vapour phase and vent system is dependent on the autoclave operating pressure and temperature conditions and therefore titanium ignition prevention controls typically include process interlocks and operating procedures based on the selected nominal design operating conditions. However, it is not uncommon for these controls to be deficient or for operations to deviate from the nominal operating conditions over time, increasing the risk of titanium ignition. The introduction of an online calculation of autoclave overpressure and a maximum target autoclave pressure as well as associated process control interlocks and permissive conditions can alert the autoclave control room operator and prevent an elevated oxygen concentration from developing, and therefore reduce titanium ignition risk in autoclave vent systems."

Jan 1, 2016

By Donald J. MacNeil

THE opinion, based upon geological knowledge, that certain areas within the Province of Nova Scotia might yield commercial quantities of petroleum, is not new. It dates back to at least 1864, when the Pioneer Oil and Salt Company drilled some shallow holes in search of oil near lake Ainslie, Cape Breton. As a matter of fact, several companies were engaged in oil exploratory work near lake Ainslie at about that time; included among them were the Inverness Oil and Mining Company, the Victoria Oil Company, the American Oil Company, and the Cape Breton Oil and Mining Company. Oil exploration by these and other companies was conducted sporadically on Cape Breton island until 1914. In several instances, the depth of the test holes exceeded 1,000 feet; the deepest was carried to 3,260 feet. The Lake Ainslie area was selected because oil seepages were present along certain sections of the lake shore, but the tests that were drilled to tap the oil-bearing zone failed to yield anything of commercial value. Currently, there are three areas in Nova Scotia wherein active exploratory work is being conducted, namely, at Pugsley Siding close to Amherst; at Kennetcook, Hants county; and near Mabou, Inverness county. The Pugsley Siding test is being drilled by the Sun Oil Company, of Philadelphia; the work at Kennetcook is under the direction of the Nova Scotia Oil and Gas Company; two relatively deep holes were drilled by the Lion Oil Refining Company in 1944 near Mabou, and, as a result of the additional geological information derived therefrom, another test probably will be drilled by this Company in the same area. Aside from these activities in the search for petroleum, the oil possibilities of several other sections of the Province are being studied by means of surface geological mapping.

Jan 1, 1945

The following description is based on the film's narrative script: The film opens with a description of the terrain--tens of thousands of yearly snows compressed into glacial ice, stretching further than the eye can see. A single massive frozen cap--1 812 992 km2 (700 thou- sand sq miles) covering most of the land mass of the world's largest island, christened strangely enough--Greenland. Greenlanders comprise more than two-thirds of the 40 thousand Danish subjects who brave the elements in the Arctic Circle. Along the coastal fringe where the Gulf Stream sheds its last vestige of tropical warmth to temper Greenland summers, tiny villages survive In virtual isolation. Jagged fjords and creeping glaciers are barriers to conventional communication. There are no roads through the year-round ice. Yet, when there is wealth in the land, there are people to tame it, harnessing those unrelenting forces of nature if they can building and surviving in spite of them if they must. Near the tiny site of Marmorilik in west Greenland a gathering of men from places more benign came to challenge a sheer, frozen rock named Black Angel Mountain to tap a deposit of lead and zinc ore. As far back as the 19301s, surface investigation showed zinc and lead sulfides in the vicinity. In the mid-60's mountaineering geological examinations were made and deep-hole drilling, directed by Cominco Ltd., of Canada, confirmed the presence of an ore body, 600 m (2000 ft) above the fjord. These findings led to the formation In 1965 of Greenex A/S, a'Danish company with principal offices in Copenhagen. A utilization con- cession, with rigorous safety standards and environmental controls to

Jan 1, 1977

By B. Samanta

A quality characteristic analysed through construction of the Shewhart control chart is required to be normally distributed. In mining applications, this assumption is often violated as many quality characteristics follow skewed or lognormal distribution. In this paper, two methods were investigated using a heuristic approach for setting up the control limits for a skewed population. Based on these approaches a Mode chart, and a Weighted Variance (WV) control charts were constructed. The performance of the proposed methods was compared with the normal based Shewhart method through a case study conducted in a surface mine supplying iron ore to a steel plant. A simulation study was also conducted to evaluate the effectiveness of the proposed methods over the Shewhart method. The study revealed that the Shewhart control charts generated more out of control alarms compared with the Mode and Weighted Variance control charts for a skewed population of Fe%. The simulation results also revealed that for extremely high skewed population, the WV control chart and Mode control chart provided higher probability of coverage than the Shewhart method; although the detection rate (probability of detection) of out of control condition for these methods was slightly reduced compared with Shewhart method.

Jan 1, 2004

By E. Pallumbo, N. Szwedska, R. Asselin

"This paper highlights the results of collaboration between geology, mining and mineral processing teams during the restart of the North American Lithium Project, located near La Corne, Quebec, Canada. This collaboration was central in ensuring a cross discipline harmonization of design parameters and key inputs, all of which allowed for the development of an optimized life of mine plan suited to the particular needs of the operation.INTRODUCTION In July 2016, North American Lithium Inc. (NAL) began the process of restarting operations at the former Quebec Lithium Mine, located in the municipality of La Corne, Quebec, Canada. The North American Lithium Project (the Project) as it is known today, is the latest chapter in the history of this property. In order to provide a robust foundation for the project, multidisciplinary collaboration was instituted between the geology, mining and metallurgy teams. Despite the intrinsic link between these departments, in many instances their work is completed separate from one another; in silos. This collaboration highlighted specific drivers in the mining value chain that could be exploited to ensure that a saleable product could be produced effectively. This paper explores some of the concepts and strategies that were developed during the feasibility study that supported the project restart (excerpts from the study technical report have been used throughout this paper). PROJECT HISTORY In 1942, prospectors identified the presence of numerous spodumene-bearing pegmatite dykes on the Property. This led to additional interest and exploration drilling campaigns. In 1955, Quebec Lithium Corp. (QLC), who had acquired the property, began construction of an underground mine with mill facilities located on the surface. Operations began the following year at a production rate of 1,100 tonnes per day. A historical cross-section view of the underground mine is shown in Figure 1. In 1959, QLC began the construction of an on-site lithium refinery to produce lithium hydroxide. The refinery was finally operational by 1963. Mining and processing operations continued until 1966 when activities were halted due to a labour dispute. The property was sold and a few years later attempts to resume production were unsuccessful. Property ownership changed several times again until being acquired by Cambior in 1987. In the early 1990’s the existing mine and mill facilities were sold and the mine site rehabilitated"

Jan 1, 2019

This paper deals chiefly with the preliminary examination, when a decision has to be made as to whether a prospect has a chance of developing into a mine or not. At this stage it is important to have a fairly clear conception of what is expected of the prospect, andjust what type of mine is sought. Much money can be wasted testing a prospect suitable for a prospector or small syndicate, but which never looked like becoming a mine of sufficient size to interest a company. When undertaking an inspection, therefore, it is necessary to have a broad outline, at least, of the policy of the principals for whom the report is intended.At this early stage it is frequently necessary to form an opinion of the prospects of a property on very meagre data. When new to this type of work one's first reaction is often th~t it is impossible to pass an opinion on the data available. It. is absolutely necessary,however, that an opinion of the possibilities and chances of favourable development be given; The report should strive to convey this information, making quite ::lear the risk involved, how complete are the data on which this opinion is based, and the possible magnitude of the prize. A Preliminary report has to state whether a property has sufficient prospects to warrant testing.The following procedure is suggested in order to make best use of the data and minimise hasty conclusions influenced by preconceived ideas-an ever-present danger.Examination.The first stage is the examination. This should aim at collecting all available significant data, but avoid clouding the issue with detail which, at this stage, will not affect the decision. The following points are considered to be the main ones for which to look:-Geological Environment.As good a working knowledge as possible'of the geology of the area should be obtained. Government Geological Survey reports and maps, if available, will be a big help. A detailed knowledge of the regional geology is not necessary a,t this stage, but a broad outline of the geological setting of the prospect under review, and also of any other important mines in the district, is often helpful in the final decision.The Nature of the Ore-Body.Any facts concerning the nature or occurrence of the lode should be noted as, coupled with experience of similar bodies, they affect the ultimate decision.Structural Control.This is probably the most important factor, in the light of present geological knowledge. Its chief importance is due to two facts:-(a) Structure plays one of the prime parts in ore deposition.(b) Geological knowledge, of structure is somewhat in advance of knowledge of other factors influencing ore deposition.

Jan 1, 1950

By A. E. Hilder

Introductory The following pages present the results of field investigations, laboratory and commercial tests, drilling, surveying, and preliminary development of the refractory clays which have been discovered recently in the township of Kipling, at the foot of Long rapids on the west side of the Mattagami river about 57 miles north of Kapuskasing and approximately 7 miles north of Smoky Falls, the terminus of the privately owned railway operated by the Spruce Falls Power and Paper Company, Kapuskasing (see Figure 1). Investigations on the clays of northern Ontario have been carried on over a period of seven years by officers of the Ontario Department of Mines, and I am indebted to the information published by that Department in reports by W. S. Dyer and A. R. Crozier, as well as?by Professor R. J. Montgomery, of the Ceramic Department, University of Toronto. It was, in large measure, the data given in the 37th, 38th, and 42nd Annual Reports of the Ontario Department of Mines that led me to make a personal investigation of the Mattagami River clays, with the result that we now have a commercial undertaking that will develop eventually into an industry of considerable importance in supplying the central manufacturing districts of Canada with refractories that heretofore have been largely imported from the United States. An extract from the 42nd Annual Report of the Department, Part III, 1933, page 75, reads as follows: "As for the refractory clay, the deposits are undoubtedly very large, but what is urgently needed is a deposit near the railway under sufficiently shallow overburden for recovery by stripping'. Having previously made an investigation of the clays adjacent to the Temiskaming and Northern Ontario railway, and these clays proving unsuitable, I turned my attention to the outcrops of refractory clays on the Mattagami river, first reported by Keele in 1919. This area offered possibilities within the economically permissible distance from rail transportation.

Jan 1, 1935

By G. A. Gamble

Fans used to ventilate subway, passenger rail and vehicular tunnels are similar to the fans used to ventilate underground mines. However, tunnel ventilation fan systems are typically designed to meet NFPA 130 or 502 standards, while mine ventilation fan systems must comply with the appropriate federal mine safety regulations. As a result, fan operation requirements and performance criteria, as well as typical fan and duct configurations differ significantly for tunnel and mine ventilation applications. Variations in environmental conditions in tunnels as compared to mines also result in differences in fan performance and material specifications. The need to enclose tunnel fans within building structures creates space restrictions impacting fan size selection that are not commonly encountered in mine fan installations, resulting in different approaches to selecting fans for the two types of tunnels. This paper discusses the various similarities and differences in design considerations for tunnel and mine ventilation fans.

Jan 1, 2009

By K. A. Lewandowski

Leach heaps are plagued with problems due to fine material migrating downwards, clogging the spaces between the coarser ore particles, resulting in decreased metal recovery rates. The use of a binder in agglomeration would allow the fine material to be immobilized, increasing the availability for the solution to come in contact with all the ore. As much as 1.64*1012 BTU per year would be able to be saved if a 25% increase in copper recovery was experienced, assuming that 70% of heap leaching units converted to using agglomeration technology. This is equivalent to approximately 18% of the energy currently being used in leaching heaps.

Jan 1, 2008

By Jas. E. Thomson

PUBLIC attention was first attracted to the Crow River area of north-western Ontario by the discovery of gold in 1928. The first three discoveries were eventually developed into Central Patricia, Pickle Crow, and Albany River mines. In 1929, preliminary developments were carried out at the Howell vein on N.A.M.E. (later Pickle Crow) claims, and in 1929 and 1930 surface and underground work indicated an ore-body at Central Patricia mine. However, due to the financial depression and the distance of these properties from the railway, it was not until 1934 and 1935 that, benefitted by the revaluation of gold, the real potentialities of these two properties began to be realized. Their immediate success led to a resumption of activity on neighbouring properties throughout the area in 1936 and 1937. Preliminary prospecting in the earlier period had been limited by the scarcity of rock exposures in the country. The procedure in the recent programme of intensive exploration has been along similar lines at most properties and has consisted lf detailed geological mapping accompanied by geophysical surveys and followed by systematic drilling of favourable zones. The present importance of the camp may be judged by the fact that, in 1937, Central Patricia and Pickle Crow mines together produced bullion valued at $3,662,953, and paid $1,450,000 in dividends. In addition, there were pro-mising gold developments at Albany River mine. During the past two seasons, the Geological Branch of the Ontario Department of Mines has been making a fairly detailed study of the geology and mineral deposits in the Crow River area. It is the purpose of this paper to present a brief statement of some of the structural features of these deposits; a summary of other geological information essential for the understanding of the main topic is included. A more detailed report on the area will be published shortly by the Ontario Department of Mines. It is impossible to make full acknowledgment here for all help received, for the writer is in-debted to the management, staff, and consultants of every Company in the camp for generous co-operation in the field and for information, plans, maps, and records placed at his disposal. Reports and articles on properties in the area have been written by Hurst (1), Cormie (2), Reid (3), and the staff of Pickle Crow Gold Mines ( 4).

Jan 1, 1938

By Jr. Gabler

World resources of cobalt appear ample for the foreseeable future; however, political and economic events have caused concern over the availability and reliability of an uninterrupted supply. Because of this concern, the U.S. Congress requested that the U.S. Bureau of Mines initiate a study of the flow of cobalt in the economy that would delineate and quantify the production areas where metal values are lost. As a result, the Bureau has developed a computerized commodity flow model. A major attribute of this model is that it is amenable to updating as supply, demand, and/or production data change. This report follows the flow of cobalt through its metallurgical and chemical applications and highlights areas where significant losses occur due to downgrading, export, or disposal. The study indicates that about 4,300,000 lb of cobalt-bearing materials are lost each year, representing 24 pct of U.S. domestic demand.

Jan 1, 1990

By B. C. Peterson

Calumet Division, Calumet & Hecla, Inc., whose operations are in Houghton and Keweenaw Counties, Mich., is a highly integrated and complex organization. This division operates mines, a railroad, a concentrating mill, a reverberatory smelter, and the auxiliary generating plants and shops to service these operations. In addition, it operates a sands reclamation plant, leaching plants, a foundry, and a machine shop that serves varied industries with castings and parts for many applications. Calumet & Hecla, Inc. has produced over 60 percent of all the copper that has been produced in Michigan since discovery of the ore in 1864, and in 1959 the company ranked eight among the country's producers with a production of 17,407 tons. To keep abreast of modern accounting systems developed elsewhere in industry and to combat increasing costs due to higher labor and supply costs, as well as increased costs due to deeper mines and lower grade ore, the company has developed a modern machine cost accounting system. This not only provides the usual bookkeeping and cost accounting facilities but offers accurate cost data for engineering evaluation of the mining operation. This system is credited with being instrumental in permitting continued operation of these high-cost mines in a period of increasing costs with no corresponding increase in the price of metal.

Jan 1, 1962

The Carlin gold deposit is located in northeastern Nevada about thirty-five miles by road from the town of Elko. Following the staking of six square miles 'of ground, a drilling program outlined a fine ore body mineable by open pitting. The resulting mine turned out to be the largest open-pit gold operation in the world, until the Rosario Pueblo Viejo operation was started in 1975. Because of the high profitability forecast at the then $35 gold price, construction of a 2000 stpd mill was commenced on a crash program and was completed for Newmont Mining Corporation by Bechtel Corporation in ten months. Production was started in early 1965. The gold mineralization occurs in marine-type sediments, chiefly silt- stones and limey shales, and the ore characteristics make for a difficult materials-handling problem. At 5% to 6% moisture the ore is dusty during crushing, but even a light rain or snowfall virtually turns the material into a slurry. Crushing this sticky ore below 314 in. (19 mm) in the dry season and 1 in. (25.4 m) during the winter is extremely difficult and leads to problems with conveyors, chutes, and fine ore storage. The initial flowsheet for Carlin's crushing plant used a 5 ft by 22 ft (1.52 m by 6. 7 m) vibrating feeder -grizzly under the 60 -ton dump pocket for feeding the 42 in. by 48 in. (1067 mm by 1220 mm) single toggle jaw crusher and a 5 ½ ft (1.52 m) standard cone crusher in closed circuit with a 6 ft by 12 ft (1.83 m by 3.66 m) vibrating double - deck screen. Because continual packing of fines in the vibrating feeder pan would cause frequent plant shut-downs to remove the fines with jack hammers, the decision was made to replace the vibrating unit with an apron feeder and stationary grizzly ahead of the jaw crusher. A dribble belt was also installed under the apron feeder. This installation has greatly improved the feeding of the pit run ore to the .primary jaw crusher. Mining at Carlin is done by a 5 yd shovel and 7 ½ and 10 yd front-end loaders, and ore transport is by several sizes of trucks from 30 to 75 tons capacity. These pit haulage trucks dump onto stockpiles adjacent to the primary crusher. Ore is then fed to the dump hopper by front- end loaders only when the crushing plant is operating. This extra handling procedure is necessary because plant delays caused by problems with wet ore in the secondary crusher resulted in the ore setting up or packing in the dump pocket. Solidified material in the dump pocket would in turn delay truck haulage. The substitution of an

Jan 1, 1978

By P. Matias

The study involved two projects that will produce copper concentrate and may have their operations integrated. Transport by trucks, conveyor belt, and the equipment called RopeCon were evaluated as options for the ore transport between the sites. A rainforest stretch, that Vale S.A. demands to preserve, is situated between the projects. It was suggested to further review RopeCon because it presents minimal interactions with the environment. To design the preliminary system layout, a research was done on the rainforest cover height data, but the information found was scarce and imprecise. For preserving the local forest, the use of this data would conduct to the oversizing of RopeCon towers and, consequently, overestimation of its costs. For the acquisition of reliable information, a method was developed using local data acquired through airborne laser survey. The volume between the digital surface and terrain models was calculated to generate a surface representing the forest cover height. It was revealed, by plotting the points obtained from this surface, that 85% of the vegetation is below 25 m. This height is suggested to review the preliminary project with a more accurate design of the equipment towers, thus reducing its costs estimates. The method permits the precise location of the large trees, making easier to find a pathway, for linear-shaped facilities, that would minimize the creation of vegetation-free zones as a measure to protect equipments against falling trees and forest fires. Keywords: forest cover, mining projects facilities, digital models, airborne laser survey

Sep 1, 2012

By D J. Gray

The 4 km long Huguenot Toll Tunnel in the Western Cape region of South Africa celebrated its tenth anniversary on 18 March 1998. At present a single (South) bore with bi-directional traffic flow is operational. The North bore was originally excavated but not lined and equipped.The tunnel is fitted with a semi-transverse ventilation system comprising 45/350 kW two speed fresh-air and 1 MW exhaust air fans at each of the portals. These provide ventilation through fresh and exhaust air ducts above the ceiling separated by movable partition doors. Secondary air ducts deliver air at low level. The fan control depends on the levels of CO pollution or visibility measured at six positions along the tunnel.The system performed well during initial tests and under conditions of low traffic volumes. As traffic volumes increased, and user complaints of bad air in the tunnel were received on several occasions, we realised that we had a problem. Tests confirmed that natural airflow within the tunnel induced by prevailing meteorological conditions outside the portals affected the performance of the ventilation system causing a plug of bad air to be trapped at varying positions along the operating tunnel.The control systems in the tunnel are presently being upgraded as described by Gray, Rieckert and Bullock (1998). As part of the retrofit we are implementing a new control strategy for the ventilation system which takes into account the external weather conditions. This paper discusses the 24 month long meteorological data gathering exercise, which is on-going, and explores the philosophies planned for controlling the ventilation system. The correlation between winds external to the tunnel and induced airflow inside the tunnel are examined. The effects of the weather induced airflow on the existing ventilation system are considered and proposals given for taking these effects into account in the new control strategy. These include the implementation of an expert system to predict ambient airflow from prevailing weather conditions, and the use of airflow measurements taken in the uncompleted North bore as a cross-check.The paper highlights the need to take cognisance of external weather conditions when designing tunnel ventilation systems.

Jan 1, 1999

By C. W. Allen, L. C. Moore

THE Mather mine, of the Negaunee Mine Co., is within the limits of the City of Ishpeming, on the Marquette iron- range in Michigan's Upper Peninsula. It is named for William G. Mather, who has served as President, and Chairman of the Board, of The Cleveland-Cliffs Iron Co. for well over 50 years. The property comprises nearly the square mile of section 2, T.47 N. R.27 W., which, except for 20 acres in the northeast corner, was leased by The Cleveland-Cliffs Iron Co. to the Negaunee company. The latter is a partnership of Cleveland-Cliffs and the Bethlehem Steel Co., organized to equip the property, retaining Cliffs in charge as operator. Shipments of ore from this area are mainly through Marquette, which is 16 miles to the northeast on Lake Superior, or through Escanaba, a Lake Michigan port, 65 miles to the south. Cleveland-Cliffs, in 1943, operated 12 mines in the Lake Superior district, with shipments of 6,635,576 tons for the year. GEOLOGY The north footwall of the Marquette Range synclinorium outcrops near the north line of sec. 2, the iron formation dipping to the south at an angle of about 40º. The south side of the trough reappears at a distance of 4 ½ miles on sec. 26 and the surface geology between shows iron formation or intrusive diorites. The latter are harder than most phases of the iron formation and, as a result of glacial action, appear as buttes or low-lying hills. The general elevation of sec. 2 is about 1450 ft. above sea level, or 850ft. above Lake Superior, and the higher diorite outcroppings about 1600 ft. above sea level. The geological structure has been complicated by a series of major and minor faults, one of which may be illustrated by the diorite sheet, which tilts south with the iron formation in the north half of the section and then reappears near the center to repeat this sequence. Sectionally the geological series includes a nearly eroded capping of Goodrich quartzite followed by the considerable thickness of Negaunee iron formation, which is cut by intrusive dikes or diorite sheets, and underlain by the Siamo slates grading into quartzites. The ore deposits occur mainly in troughs formed by the intersection of impervious dikes and the footwall slate, but include locally enriched lenses or bands in the iron formation and also interbedded with the Siamo slate. The ore is a soft red hematite with an indicated dried analysis from the surface drilling to date of 61.50 per cent Fe, 0.134 per cent P, 5.40 per cent Si, 2.87 per cent Al and 0.015 per cent S. EXPLORATION A diamond-drilling campaign started in 1937 actually had its inception in 1917, when a number of shallow test holes were put down for the purpose of locating ore that might be quickly developed and mined

Jan 1, 1945

By Arthur W. Griffith

Ozark Lead Company, a wholly owned subsidiary of Kennecott Copper Corporation, was formed in 1961 to operate in the State of Missouri. The orebody presently being mined was discovered in January of 1962, and over a quarter of a million feet of drilling was done to determine its value and extent. In addition, a development shaft, six feet in finished diameter, was drilled into the orebody by an oil field rig in order to support the results of the core drill samples and to obtain bulk samples of ore for metallurgical pilot plant testing, upon the results of which the primary flowsheet was established. The design criteria developed from the flowsheet was based upon a 6000 TPD plant throughput and the subsequent engineering and construction of the mine and concentrating plant was completed in June 1968. The plant, which is designed to mine and mill 6000 tons of ore per day and produce 60,000 tons of lead and 8000 tons of zinc in concentrate annually, is located approximately 110 air miles south- west of Saint Louis. MINERALOGY The orebody occurs in the Bonneterre dolomitic limestone formation in the form of irregular masses of disseminated sulphides in essentially horizontal beds. The Lamotte sandstone underlies the Bonneterre formation and is barren in values. Principal ore minerals include galena with lesser amounts of sphalerite and some copper minerals. Galena is found to be massive

Jan 1, 1970

By Joshua Micah Hoffman

While it is easy to state that meaningful involvement of the community can play a critical role for a successful blasting operation, following through with this involvement is not an easy task. Structured Public Involvement (SPI) is a developed protocol for involving communities in project planning decisions and could be readily applied to the blasting industry. SPI was developed for the purpose of collecting quality public input about public transportation projects. The purpose of SPI is to bring about stakeholder satisfaction with potential projects by allowing controlled input from the stakeholders. It was designed and intended for democratic societies that have come to expect a voice in public projects. While blasting operations are not always in the domain of public projects, the fundamental process outlined by SPI can be useful for collecting feedback from the immediate public around blasting operations.

Jan 1, 2014

By K. Ramji

"The development curve in the extractive sector has become longer, steeper, and riskier due to increased social, legal, and political risks from various stakeholders. Indigenous peoples are a unique stakeholder because their growing legal rights to lands and resources can often determine a project’s outcome. A project will only be successful if it is able to obtain the legal permits, withstand any judicial reviews, and gain and maintain the social license to operate. Stakeholder identification, management, and engagement are key risk-mitigation tools required to successfully convert risks into opportunities.RÉSUMÉ La courbe de développement du secteur de l’extraction s’est allongée, elle est devenue plus abrupte et plus hasardeuse en raison de l’accroissement des risques sociaux, légaux et politiques venant des divers intervenants. Les peuples autochtones sont des intervenants uniques puisque leurs droits légaux croissants sur les terres et les ressources déterminent souvent ce qu’il adviendra d’un projet. Un projet ne pourra réussir que s’il est capable d’obtenir les permis légaux, passer à travers les analyses judiciaires, puis obtenir et maintenir le permis social d’exploitation. L’identification des intervenants, la direction et l’engagement constituent les outils clés de l’atténuation des risques nécessaires pour bien convertir les risques en possibilités."

Jan 1, 2016