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By Eugene Guccione

The US mining industry today is fighting for its existence. We are plagued by the shortage of materials, of equipment, of fuels, of capital, of manpower. If we solve those shortages, we are then frustrated in our attempts to open a new mine or, perish the thought, a new smelter. If we manage to make a profit, demagogues will accuse us of stealing from consumers; and, if we do not make a profit and have to shut down, the same demagogues will accuse us of creating unemployment. Meanwhile, in every aspect of our business - from research, exploration and development, to production, marketing and selling - we are hindered in every way by the bipartisan mismanagement and crippling controls of a government bureaucracy gone amok. We are fighting a war on every front. Some of you realize that ours is a war of ideas. In order to win, our industry must make its ideas heard. But to be heard, we must have something to say - which means: we must know our case logically and consistently, all the way down to essential principles. A principle is a primary truth applicable to a great number of instances. A principle is like a road map: it shows you all the possible alternatives for getting from where you are to where you want to go. Although practically everybody recognizes the usefulness of a map and the need to consult it to find the best way' to get from one city to another, most people are not as careful in charting the course of their life, or the course of their industry, or the course of their nation. And so they act blindly, at random, by the whim of the moment, and get nowhere fast.

Jan 1, 1975

By A. C. Munro

This paper, which describes the milling practice at the Britannia concentrator, Britannia Beach, B. C., is one of a series being prepared by the Bureau of Mines. The concentrator treats copper ore at the present rate of 6,000 to 7,000 tons of dry ore daily and produces copper concentrate and pyrite concentrate by selective flotation methods. The copper concentrate is smelted and the pyrite product is utilized for acid manufacture.

Jan 1, 1932

By P. Cain, B. Martens

"Grande Cache Coal (GCC), an investor-owned Alberta company, is in the final stages of the regulatory process leading to the resumption of coal mining in the Smoky River Coal Field of Alberta. Although many opportunities for low-cost, high-yield mining remained on the property, GCC opted for a long-term production plan that ensures stability for the local economy, sustainable use of the resources in the area, environmental responsibility and a satisfactory return for its investors.GCC entered the Alberta coal approval process in late 2000 with a public disclosure document. In October 2001, GCC formally submitted an application for mining approval and an environmental impact assessment (EIA) to the government and the public. The application covered the proposed Grande Cache Coal project, which includes the No. 7 underground mine, No. 8 surface mine and coal processing operations. The EIA provided a comprehensive investigation of environmental sensitivities in the project area, matched with environmental protection programs. The project is based on commencement of operations in late 2002. GCC’s plans are founded on a commitment to sustainable development and has framed this commitment in the context of a long-range mine development plan that will sustain the community of Grande Cache over the next 25 years. The Grande Cache coalfields offer extensive coal reserves and opportunities, for both surface and underground mining. Combining highly productive U.S.-style room and- pillar underground mining methods and conventional truck-and-shovel open pit mining, GCC’s approach to sustainable development encompasses community involvement and reclamation of mine sites to productive land uses after mining."

Jan 1, 2002

By H. R. Taylor

The history and development of this property is more or less familiar to nearly everyone connected with the mining industry, so that only a brief outline of the more important facts will be given in this article. In 1916, a small pilot mill was constructed by the British Columbia Copper Company at Copper Mountain, and during 1916 and 1917 test work was conducted to determine the possibility of concentrating the ore and also to work out a suitable flow-sheet. In the spring of 1917, the location of a mill site at Allen by, which is about 8,% miles from Copper Mountain, and near the Similkameen river, was decided on, and the designing of a 2,000-ton plant was then worked out by Bradley, Bruff and Labarthe. Early in 1918, the actual construction of the concentrator began, and, after considerable labour difficulties, it was completed in 1920. During this period of construction, the West Kootenay Power Company ran a 60,000-volt power line over from Greenwood, a distance of 102 miles, and also built a sub-station at Allenby to take care of the mine and mill. The concentrator was started up on October 20th, 1920, and ran until December 11th, 1920, a total of 18,354 tons of ore being milled. The results of this short period of operation were encouraging, but, due to tlie prevailing low price of copper and high wages, it was necessary to shut down until a more favourable time. During the latter half of 1923, some work was done on remodelling the mill. This work continued until January 8th, 1924, when it was suspended.

Jan 1, 1929

By E. Bauer, S. Moore

Technological advances in underground coal mining have led to a reduction in fatalities. This study demonstrated that the percentage of cumulative injuries remained largely unchanged across two decades of technological advances (1983-1984: 37%; 2003-2004: 33%). Furthermore, it was demonstrated that the average number of lost days due to cumulative injuries has increased (36±55 days and 62±82 days, respectively) which may have been due to the increased age of the work force or an increase in length of employment meaning that the mine workers injured in 2003-2004 had been exposed to ergonomic risk factors longer than those in 1983-1984. It is recommended that ergonomics processes be implemented as a means to systematically identify, prioritize, and resolve the root causes of these cumulative injuries.

Jan 1, 2007

By Kenneth D. Winters

This Bureau of Mines report presents a Fortran IV computer program for the structural analysis of (1) protective canopies used in underground mines to protect equipment operators from roof falls and (2) rollover protective structures (ROPS) used in surface mines to protect equipment operators during vehicle overturn accidents. The program, entitled PLASTIC CANOPY, permits rapid and inexpensive calculation of the ultimate strength and deformation characteristics of a canopy for a variety of static loading conditions. The structure is modeled as a series of interconnected beam and/or plate elements. Stresses in, and displacements of, each structural element are computed and printed out at the yield strength of the canopy, at several intermediate load levels between the yield and ultimate strength of the canopy, and at the ultimate strength of the canopy. Other features of the program include prediction of buckling of a beam member under combined axial compression loading and bending, plotting of the input geometry of the structure, and plotting of the deformed shape of the loaded structure. Program description, input instructions, program listing, and four example problems are included.

Jan 1, 1979

By Jerry D. St. Clair

A multidisciplinary team of scientists and engineers at Wont has been working to understand heavy metal contamination of DuPont process waste streams and technologies for abatement of these metals. As part of this effort, an extensive study was made of a specific waste stream of importance in DuPont's environmental commitment. This 200 gpm stream contains 5-5000 ppm of nickel plus a variety of inorganic and organic constituents. The chemical complexity of the waste rendered conventional. alkaline precipitation ineffective, and only through the simultaneous application of analytical characterization, fundamental chemical understanding, and process engineering did effective technical approaches emerge. In this instance, ion exchange, sulfide precipitation, and caustic digestion ultimately proved successful in reducing the nickel to below the 1 ppm target. The results of this study will be presented, along with key learnings about the process of solving heavy metal contamination problems.

Jan 1, 1994

By Donelson A. Robertson

Literature was searched and cases of alleged water well damage were investigated. Occurrence of ground water in Appalachia is primarily in low yield, fractured, water table aquifers. Four test sites were chosen based on geographic and geologic diversity. Test wells were drilled at each site and base line data on water quality, static water level, and drawdown characteristics were obtained before surface mining commenced. Blast induced ground vibrations were measured at the surface by the wells at levels up to 5.44 inches per second maximum resultant particle velocity. Measurements made at the bottom of wells indicated that vibrations were considerably attenuated at depths of 140 to 160 feet. No direct evidence of change in water quality or well performance was produced by blast vibrations, but removal of downslope support by excavation does cause lateral stress relief which permits the water-bearing fractures to become more open. This additional storage capacity causes the static water level to drop and for well-bore permeability to improve. Static water level recovers if sufficient recharge is available and well performance is

Jan 1, 1980

By Min-Min Lin, Bing Xie, Hong-Yi Li, Yang Yang

After precipitation of ammonium vanadates from vanadium-containing leaching liquor, vanadium (V(V)) and chromium (Cr(VI)) exist in the waste water in form of vanadate ions and chromate ions. In order to efficiently extract and recover V(V) and Cr(VI) from waste water, an environment-friendly method based on anion exchange was investigated in batch tests using macroporous weak base resin Dex-V. The adsorption conditions optimizes in detail, including the effect of pH, initial metal concentration, resin volume, contact time and temperature. The ion-exchange adsorption process for both V(V) and Cr(VI) showed maximum capacity at pH 3.0 for an initial concentration of 100 mg L−1, and reached equilibrium after about 40 min of contact at 298 K. The maximum adsorption ratio under the optimum conditions for V(V) and Cr(VI) was 98.98 and 99.87%, respectively. Result shows that the established method is a promising alternative for simultaneous extraction of vanadium and chromium.

Mar 1, 2018

By M L. van Kampen

The recent (2005) amendments to the Resource Management Act 1991 have made it clear that there is no obligation on an applicant to consult. However the importance and value in consulting with the community, particularly before commencing a major project, cannot be understated.   This paper looks at the provisions of the Resource Management Act as they relate to consultation and public participation in the process, and will discuss the benefits of consultation both before an application is filed and following the filing of the application. Engaging with the local community can help shape a project to better fit the community, engender support and address opposition. In short, taking the extra step to what is legally required, can help smooth what is potentially a bumpy road. Examples in practice of the value of consultation are given.

Jan 1, 2006

By Tasuku Fuwa, John Chipman

Equilibrium data on the reactions of gases with carbon and oxygen dissolved in liquid iron are reviewed and correlated. A source of error in oxygen analysis of graphitic samples is exposed. New experimental data on the oxygen content of high -carbon iron in equilibrium with carbon monoxide indicate that the activity coefficient of oxygen is decreased by additions of carbon. The carbon-oxygen product decreases slightly with increasing carbon content. In recent years a number of investigations have been reported dealing with the equilibria between carbon and oxygen in liquid iron and gases containing carbon oxides. The laboratory study of these reactions dates back to 1931 with the publication of a paper by Vacher and Hamilton' on "The Carbon-Oxygen Equilibrium in Liquid Iron". The principal object of this study was to obtain data on the reaction shown by Eq. [3] below; their data and others by vacherZ permit evaluation of the other equilibrium constants as well. Subsequent studies have been reported by Matoba, Phragmen and Kalling and by Marshall and Chipman.5 The equilibria may be expressed by the following three equations: C + CO,= 2CO;Kl = Pc° [1] 0-+CO = CO,;K2=-P co, "0.PCO c + O = CO; K3 = In the equilibrium constants, ac and a0 are taken as equal to [% C] and [% 0] respectively in the infinitely dilute solution. At finite concentrations an activity coefficient is introduced such that ac =fc [%C], and so forth. It is to be noted that these equations represent only two independent relations, the third being derivable from any two. Richardson and Dennis have determined the conditions of equilibrium in reaction [I] at temperatures of 1560" to 1760°C. Their results have been confirmed by Rist and chipman7 who have shown how the data may be extended to cover the entire range of liquid compositions at temperatures from the eutectic up to 1760°C. An approximate confirmation has been reported by Fuwa and chipman.' These investigations also established the activity coefficient of carbon which was shown to increase rather rapidly with increasing concentration. For the very dilute solutions the value of Kl is expressed in the equation: log^i = - 7280/T+ 6.65 This equation leads to a value of Kl = 430 at 1540° C in excellent agreement with the average value of Marshall and Chipman.5 It is shown as line 1 in Fig. 1 together with the experimental observations. In the case of reaction [2] the direct experimental results can be supplemented by observations on the corresponding reaction with hydrogen, namely reaction [4]:

Jan 1, 1961

MR. J. F. MYERS, Consulting J3eneficiation Engineer, Greenwich, Conn.: In the written discussion contributed by Mr. F. C. Bond in item ( 2) (page 515), speaiking about the significance of the ratio of mill diameter to the make-up ball diameter, he states: "When this ratio exceeds 100 the power and capacity of the mill are de-creased"; and the paragraph ends with a reference to the 30 per cent ball volume "with some de-crease in mill capacity". I believe this broad statement is incorrect. When we are dealing with a non-cataracting mill, pre-ceded by a good rod mill, there is a slight increase in capacity, but the power does drop. The second point that I consider needs consideration is Mr. Bond's item (8), Proper Mill Speed (page 516). This paragraph should be qualified to cover single-stage mills only. It does not apply where a rod mill is followed by a non-cataracting ball mill. The statement as is, with no qualification, gives an erroneous idea of proper mill speeds.

Jan 1, 1957

By AIME AIME

MINERAL production of the United States is valued at over five billion dollars a year at present and the industry employs close to a million workmen, yet such maps as are available that might indicate the geographical distribution of this industry show only the location of coal and oil fields and of other mineral deposits. No recent map is available that shows this distribution in a quantitative way. The purpose of the maps and graphs here presented is twofold: (1) to give the mining engineer a clear conception of the relative value and the pattern of distribution of minerals in the United States; (2) to test the so-called block-pile (or grouped pillar) system of statistical mapping, which makes this presentation possible. (I discussed this method of mapping in an article which appeared in Economic Geology in 1939, Vol. 15, p. 185-188.)

Jan 1, 1941

By G. Auld

"A simple method is presented whereby the additional quantity and static pressure necessary to compensate for ventilation duct leakage may be estimated using the circular reference functions of modern spreadsheets. Favourable comparisons have been made to the National Coal Board (United Kingdom) design charts and to a case study analysis. IntroductionIn mining, most ducted systems are applied to the development of access tunnels, and most of these systems leak to some extent. When the ventilation duct fails to deliver the required quantity of air to the work place, there is a significant contribution to the development costs, either directly or indirectly.Directly — More air and more pressure are required to compensate for the leakage, more capital development (ventilation shafts, parallel drives) are required because ventilation systems cannot push the fresh air far enough, and longer re-entry times to ensure toxic blast fumes to be diluted.Indirectly — There is a reduction in productivity because of the inclement atmospheric conditions, and/or closure of development ends because of unacceptable atmospheric conditions at the working place. This has been exacerbated over the last few decades because of the increased use of diesel equipment of ever increasing power, and the more stringent Occupational Health and Safety requirements demanding more air flow per kilowatt of diesel power.The leakage from a duct must, therefore, be reliably estimated in order to assess the effectiveness and construction of the system; assess the effectiveness of the maintenance or repair of the duct; appreciate the cost of the leakage, and therefore apply effective maintenance and installation procedures; and engineer safer, healthier and more cost-effective ventilation systems."

Jan 1, 2002

By M. H. Kline

The Cranberry magnetite deposits occur in pre-Cambrian granite-gneiss, in a belt extending from 3 miles southeast of Cranberry, N. C., to about 6 miles southwest of Magnetic City, Tenn. The belt forms a curve) elongated to the north, approximately 26 miles in length. The Bureau of Mines investigation has been confined to the eastern part of the belt, comprising the area from Fork Mountain, Avery County, N.C., to the Hcupscup Knob prospects in Carter County, Tenn. The deposits were worked at least us early as 1820. The Cranberry Iron & Coal Co. and its successors operated the Cranberry mine intermittently for about 50 years until 1930, when operations were abandoned.

Jan 1, 1948

By A. V. Wilke

The metallurgical balance is a tool usually applied in the mining industry. The final result is used for different objectives. All the existing software for the calculation of the metallurgical balance fits the numbers in such way that a logical correspondence between the input and output materials exist. Nevertheless, the accuracy of the metallurgical balance strongly depends on the quality of the input data. Division El Teniente of Codelco Chile has been optimizing the metallurgical balance system the last 14 years. As well, it has participated in the development of corporate norms to optimize the operations of sampling and weighting systems. As a consequence, the precision and the accuracy of the metallurgical balance have been improved in a significant way. Also the understanding of process variability was enhanced. The improvements have allowed Codelco to discover and minimize hidden losses and to better support top management decisions. The present paper describes the main aspect of the continuous improvement process.

Jan 1, 2009

VOLUME I Volume I of this three-volume report is the result of development of a comprehensive, coordinated approach to site data-acquisition activities to produce key plans and reports during the evaluation and development of a surface coal mine. A logic diagram illustrates activities in the planning and decision-making process from exploration through post-mining monitoring. The report briefly discusses major elements, other than the site environment, which influence development of mining and reclamation plans and refers to other readily available literature for details outside the scope of this study. The essence of the rationale is shown to be the 1 employment of necessary skills at the proper time to evaluate specific data ' requirements and integrate them into a cost-effective program to produce initial and major feasibility reports, mining, and reclamation plans, and the environmental impact assessment.

Jan 1, 1976

By C. L. Emery, A. V. Corlett

"The stress equilibrium is disturbed in a body of rock by a mine opening and is restored by a redistribution of the stresses around the opening. The pattern of the redistribution of unilateral stress around an opening has been established by mathematical analysis and photoelastic measurements. The pattern for multilateral stress is found by superimposition of unilateral fields. The mathematical analysts do not use the elastic moduli as parameters and they are not significant in photoelastic work. The medium is isotropic. The concept of unilateral stress from vertical loading and the classical pattern of its stress distribution around openings does not explain commonly observed failures around the perimeters of mine openings. They show evidence of compression where tension is postulated.When it is recognized that few minerals and perhaps no rocks are Hooke Solids, most rocks must be St. Venant Solids. The components have varying degrees of elasticity and viscosity. The assembly will be-have elastically to rupture under shock loading, but when loaded short of rupture will adjust viscously to equilibrium. Similarly, the highly elastic components may initiate rupture before equilibrium can be established when stress is instantaneously relieved. Polycrystalline adjustments may produce permanent deformation. The mechanics of consolidation, especially in sedimentary deposits, ac-quire a stress component normal to the direction of compaction which can exceed that of the loading. It is one source of prestress. There are others. The principles of prestress design are based on the normal beam reactions, modified by a built-in compression in the lower chord. When the beam is loaded to design limits, the lower chord retains some compression and the whole beam depth is effective in compression. Some of the . common evidences of failure in compression over a mine opening can be duplicated in a prestressed experimental model.When the triaxial stress pattern is recognized and suitable measuring techniques are devised, mine design can be done on a rational basis."

Jan 1, 1959

By Tianrui Xu, Chaohong Liu, Bangqing Ding

The authors were responsible for a series of large scale multiple chamber charge blasts conducted in the granite mountain area for making construction space on the southeast sea coast in China during 1993-1996. This paper describes the blast design and damage control of one mountain blast 320m in length and 280m in width in the vicinity of two wharfs and a dam. In order to obtain better rock fragmentation and muckpile, the explosive charge should be well-distributed in the mountain. The charge pattern, therefore, was designed with mainly 5 rows of tunnel charge in regular terrain in combination with a chamber charge in irregular topography area and the maximum burden was limited to be less than 38m. In order to protect the dam and wharfs the firing sequence was carefully arranged in 29 intervals and the distance between different charges of the same delay to the dam or wharf was taken into account as an additional delay interval based on the difference of p-wave propagating times. The maximum charge fired in an interval was also limited to less than 34t explosives through dividing the larger charge by a stemming deck.

Jan 1, 1998

By R. R. Sayers

The hazards connected with work under abnormal air conditions are becoming of increasing importance from a financial as well as a physiological stand- point, due to the extension of compensation laws to include diseases caused by dusts, toxic gases, and abnormal temperatures and humidities. The United States, with the excention of California, North Dakota, Wiscon- sin, Massachusetts, and Connecticut, is the only English-speaking country to-day where silicosis is not compensated.3 Cases of permenent total disability or death due to silicosis mar aprear in common-law courts, particularly in the States that have not recognized silicosis as an occupational disease for which compensation should be provided. Such cases have recently been tried in one State, according to a magazine editorial, not providing scheduled commensation for employees affected by silicosis, with results favorable to the claimant. Clearly established cases definitely linked with occupation as the cause may be expected to be recognized as deserving by juries and courts, and awards will be made. In one Atlantic Coast State, according to this editorial, 108 claims for silicosis, including 21 deaths therefrom, are said to have been filed against two small plants engaged in finely pulverizing quartz sand.

Sep 1, 1932