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By John H. Fowler

"Most of the aggregate used in Nova Scotia is produced from numerous glaciofluvial and ice-contact deposits scattered throughout the province. Production from bedrock sources is increasing, with most of the coarse aggregate used in the Halifax-Dartmouth area coming from quarries operating within the metro area.A recently completed provincial sand and gravel inventory mapping program has identified some ""resource-poor"" areas where comprehensive aggregate evaluation programs are underway. Although some areas of the province are experiencing aggregate supply problems, large volumes are exported to markets as far away as Bermuda.IntroductionThe Nova Scotia Department of Mines and Energy has been involved with aggregate resource studies for several years, although sand, gravel and crushed stone are not designated as minerals under the Mineral Resources Act of Nova Scotia. Our role has been to provide the aggregate industry with resource data as well as provide similar information to governmental agencies involved with municipal planning, water resource studies and environmental protection regulations. Several private consulting firms use the information in many of their site development studies.We became involved with aggregates in a rather roundabout way. Several years ago, an outcry from inhabitants of a small coastal community over the removal of sand and gravel from a local beach moved the provincial Department of Lands and Forests to take action to protect provincial beaches. We were asked by the Department to provide information and to suggest alternative sources here operators extracting sand and gravel from beaches could relocate. This request initiated an aggregate inventory survey in southeastern Cape Breton, which was later extended to cover the entire province. The initial provincial sand z and gravel inventory survey provided a series of 1:50,000 maps showing the distribution of sand and gravel deposits in the province."

Jan 1, 1982

By P. A. Croce

A total of 17 mine gallery fire tests (23 including sub-tests) were completed during this report period (10/1/76 - 11/30/77), directed at identifying a hazardous timber-set fuel-loading in a mine passageway that is otherwise free of combustibles. Results of these initial tests show that the capability of a particular fuel loading for propagating a fire is dependent upon the imposed ventilation air velocity and the ignition intensity, although this dependency needs to be better defined. It is also apparent that care must be taken when relating gallery test fire behavior to actual mine fire behavior, because of the restrictive length of the gallery. Present data indicate that some modification to the instrumentation scheme may be advantageous before proceeding with future tests.

Jan 1, 1978

By Alberto Buendía

El presente texto señala los beneficios en el control de operaciones de la concentradora de Toquepala. Entre los principales tenemos: la reducción de costos de producción por concepto de menor consumo de insumos, un mayor control de la planta a través de nuevos indicadores de gestión, se mejora la migración de información de planta al sistema SIC y se desarrolla la confiabilidad en la información contenida y proporcionada por SIC. Asímismo, la información contenida en el sistema permite obtener respuestas de mejora más rápidas al Departamento de metalurgia y operaciones.

Sep 9, 2007

By G C. Sen

All mining and quarrying operations that employ blasting to fragment and move broken ground have a price to pay for æby-productsÆ such as vibration and noise. These æby-productsÆ cannot be eliminated but they can be controlled and modern blasting techniques have improved to the point that excessive environmental restrictions can be adhered to whilst maintaining acceptable production rates and quality. Accurate measurement is the key to control, and as the environmental limits are becoming tighter, the proper way to measure vibrations from blasting operations becomes an integral part of the mining or quarrying operations. The basic vibration monitoring system consists of a primary sensor connected to a data logger and computer software for the analysis of the signal received and recorded. Currently, as with all fields of measurement, much improvement has occurred over the past decade, and electronic devices are much more accurate and reliable. Data analysis has also improved considerably with the computing power that is available to field operatives today. Mounting the primary sensor has been often overlooked in supposed æstandardsÆ with procedures such as double sided tape, resting on a flat surface provided the vibration level is less than a given amount. But if it is worth going to the expense of the monitoring equipment and manpower, surely it is worth a little extra effort to ensure the primary sensor is coupled to the ground effectively. The primary sensor must move with the ground and measure this movement; so if the primary sensor is allowed to move without respect to the ground (ie poor coupling to the ground) then a false record of the physical event will be measured. This scenario can easily be a practical reality if the primary sensor coupling method to the ground is not effective. In this study a number of mounting methods were fabricated and connected to similar data monitors and a series of ænormalÆ production blasts were used as the vibration source. These mounting devices were measured against an in-house procedure (the æstandardÆ) and the relative merits compared. A laboratory investigation was also carried out to look at the physical parameters of the æsoil and their effect on vibration attenuation of the in-house standard method.

Jan 1, 1999

By Alfredo Cámac Torres

El presente texto plantea un nuevo modelo estratégico de desarrollo en la minería donde existe la integración de otras dimensiones como lo tecnológico, financiero, político, institucional, ético, legal y riesgo. En este sentido, el desarrollo sustentable es una nueva visión holística del proceso de desarrollo que busca integrar varias áreas del saber humano, aunque el cuerpo teórico y validación práctica están todavía hoy en plena construcción. Por ello, la actividad minera necesita de nuevos modelos de gestión sobre desarrollo sustentable, que no se limiten al principio técnico, sino también como un principio ético y normativo.

Sep 12, 2011

YEAR OF ELECTION 1922. FEDERICO GIOLITTI Torino, Italy. 1917. HERBERT HOOVER Washington, D. C. 1941. DANIEL COWAN JACKLING San Francisco, Calif. 1939. HENRY KRUMB New York, N. Y. 1942. Essington Lewis Melbourne Vic., Australia 1921. C. McDERMID London, England. 1942. PAUL DYER MERICA New York, N. Y. 1913. EZEQUIEL ORDONEZ Mexico City, Mexico. 1938. A.M. PORTEVIN Paris France 1937. JOHN V.W. REYNDERS, New York, N. Y. 1937. GEORGE S. RICE Washington, D. C. 1911. ROBERT H. RICHARDS Cambridge, Mass. 1934. T.A. RICKARD Victoria, B.C., Canada

Jan 1, 1943

By Jack Kadlecik

This final technical report describes the concept feasibility study, testing, design and development effort which went into. The quick opening enclosure access cover and flame path tolerance checking system. A detailed definition of the explosion-proof multiple start threads is shown for two (2) sized electrical enclosures.

Jan 1, 1972

No. Place Date Vol. 1. Wilkes-Barre, Pa May, '71 1 2. Bethlehem. Pa Aug., '71 1 3. Troy, N. Y Nov.,'71 1 4. Philadelphia, Pa Feb., '72 5. New York, N. Y.* May, '72 8. Pittsburgh, Pa Oct., '72 7. Boston, Mass Feb., '73 8. Philadelphia, Pa.* May, '73 9. Easton, Pa Oct.. '73 10. New York, N. Y.Feb., '74 11. St. Louis, Mo.* May, '74 12. Hazleton. Pa Oct., '74 13. New Haven, Conn Feb., '75 14. Dover, N. J.* May, '75 15. Cleveland, O Oct., '75

Jan 1, 1929

By Adam Gray, Emery Gray

State-of-the-art seismographs can be employed to assist the blasting engineer in understanding the propagation of vibration waves generated by blasting. Wave traces and frequency plots are used to adjust shot loading and timing, especially around close or near- field structures. Successful close-in blasting vibration monitoring requires careful consideration of the following: Geophone locations Mounting of geophone both on structures and in the ground Differences between ground motion and structural response This presentation will discuss methods used to control and monitor blast-induced ground and structure motions. Case histories are presented to illustrate seismic monitoring used as a tool to control vibrations and guide the blaster in the design process.

Jan 1, 2005

By P. A. Plunkert, D. E. Morse, Pui-Kwan Tse, W. D. Menzie, Lucy McCartan, J. F. Papp

China’s burgeoning economy is responsible for a major share of recent world mineral consumption increases. In addition to factors traditionally recognized in market economies1 and factors unique to specific commodities, Chinese consumption now plays a major and increasingly important role in energy and mineral markets for many commodities, such as aluminum, copper, iron and steel, and oil. China has the world’s second largest economy after the United States. And its long-term importance to the minerals markets is even greater than indicated by its gross domestic product (GDP), which is currently less than two-thirds of that of the United States (Table 1). This is because China’s rising standard of living is accompanied by rapid industrialization and urbanization. Its consumption of mineral materials for infrastructure development for its very large population is significantly greater per capita than that of such developed economies as the United States, the European Union and Japan. In other words, China’s per capita production is rising at a rapid rate and will probably continue to do so for many years.

Jan 1, 2006

YEAR OF ELECTION 1913. FRANK DAWSON ADAMS, Montreal, Canada. 1922. FEDERICO GIOLITTI Torino, Italy. 1921. FRANK WILLIAM HARBORD London, England. 1917. HERBERT HOOVER Washington, D. C. 1941. DANIEL COWAN JACKLING San Francisco, Calif. 1939. HENRY KRUMB New York, N. Y. 1921. C. McDERMID London, England. 1913. EZEQUIEL ORDONEZ Mexico City, Mexico. 1935. ROBERT PEELE New York, N. Y. 1938. A.M. PORTEVIN Paris France 1937. JOHN V.W. REYNDERS, New York, N. Y. 1937. GEORGE S. RICE Washington, D. C. 1911. ROBERT H. RICHARDS Cambridge, Mass. 1934. T.A. RICKARD Victoria, B.C., Canada

Jan 1, 1942

By Holmes, George H. Jr.

The Cherry Creek tungsten district was explored by the Bureau of Mines from April 16 to August 13, 1942. This district is in north-central White Pine County, Nev., 50 miles north of Ely. Principal work was done on the property of the Cherry Creek Tungsten Mining Co. and at the adjacent Chance mine, although the entire district was examined and mapped. The exploratory work was done in cooperation with the Federal Geological Survey and comprised surveying, trenching, sampling, long-hole and core drilling, rehabilitation of mine workings, road building, drifting, and shaft sinking. The more important tungsten occurrences were explored by trenching and diamond drilling. Sixteen holes, having a total length of 2,515 feet, were drilled. The project resulted in partial development of three new tungsten deposits and small increases in the reserve tonnage of two scheelite-bearing lenses that were being mined by the company. The following pages summarize the history of the district, outline the ownership of the properties explored, and describe the physical features and mineral deposits. Mining and milling practices at the Cherry Creek tungsten mine are outlined, and the plan and results of project work are presented in detail together with surface maps, assay maps, and drill-hole logs.

Jan 1, 1950

By Augusto Constantino

"Las organizaciones trabajan permanentemente en la prevención de incidentes relacionados con la seguridad, pero nunca se tiene la certeza de evitar eventos y que deriven en otros incidentes de diferente magnitud. En la medida que el esfuerzo se concentre en evitar estos incidentes, la probabilidad que sucedan es menor, pero en muchos casos se producen por diferentes situaciones que escapan al control, entre ellas las derivadas de eventos aleatorios o que no están en el ámbito de control de la organización. No obstante, la probabilidad de ocurrencia dependerá en gran medida del esfuerzo en las actividades de prevención, y ello será directamente dependiente de la decisión de cada organización, el tipo de actividad, la estructura, la cantidad y magnitud de las operaciones, etc. Pero hay un tema fundamental que no depende de las anteriores, pero sí es relevante: la eficacia del proceso de investigación y la gestión de las soluciones derivadas de este."

Sep 1, 2017

By Paul M. Buttermore

As part of a national canvass of water use the Bureau of Mines compiled data on water requirements in the petroleum and natural gas industries for the calendar year 1962, specifically in well drilling, secondary-recovery operations, and natural gas processing plants. Total new water use in the petroleum industry of the United States, excluding refining, was 5.3 billion barrels. Secondary-recovery operations and natural gas processing plants required about 2.5 billion barrels of new water input; each of these requirements was about eight times greater than that for well drilling. Total use, including recirculated water, was 45.3 billion barrels of which 3.4 billion barrels was consumed. The greatest use of recirculated water was for natural gas processing, amounting to 38.2 billion barrels. Projections of total water use show that by 1975, 75.4 billion barrels will be used by the petroleum industry, of which 10.2 billion barrels will be new water. By 1985, the total use requirement will be 92.8 billion barrels, of which 13.1 billion barrels will be new water.

Jan 1, 1966

By Paul M. Buttermore

As part of a national canvass of water use the Bureau of Mines compiled data on water requirements in the petroleum and natural gas industries for the calendar year 1962, specifically in well drilling, secondary-recovery operations, and natural gas processing plants. Total new water use in the petroleum industry of the United States, excluding refining, was 5.3 billion barrels. Secondary-recovery operations and natural gas processing plants required about 2.5 billion barrels of new water input; each of these requirements was about eight times greater than that for well drilling. Total use, including recirculated water, was 45.3 billion barrels of which 3.4 billion barrels was consumed. The greatest use of recirculated water was for natural gas processing, amounting to 38.2 billion barrels. Projections of total water use show that by 1975, 75.4 billion barrels will be used by the petroleum industry, of which 10.2 billion barrels will be new water. By 1985, the total use requirement will be 92.8 billion barrels, of which 13.1 billion barrels will be new water.

Jan 1, 1966

By C. A. Rowland Jr

"I. INTRODUCTIONFred C. Bond's ""Third Theory of Comminution"" (1) was published in 1952. The mathematical statement of the Third Theory is the well-known Bond Formula:where W - Kw H per short tonWl - Work IndexP - Product size in microns which 80% passesF .. Product size in microns which 80% passesWork Index, as defined by Fred Bond, "" ... is the comminution parameter which expresses the resistance of the material to crushing and grinding. Numerically, the Work Index is the KwHrs per short ton required to reduce the material from theoretically infinite feed size to 80% passing 100 microns."" (2)Work indices for grinding can be obtained tram Bond grindability tests and can be calculated from plant grinding mill operating data when power consumed per ton of ore ground, the feed size analysis and the product size analysis are known.Work indices obtained tram Bond grindability tests, having been obtained from standard and controlled laboratory procedures, are reproducible and for the sample tested are accurate. The degree of accuracy relative to plant mill operation depends upon how representative the sample is of the total mill feed.The results of the Bond closed circuit rod and ball mill grindability tests (3) are given in grams of product sized material produced per revolution of the test mill. In developing a method to evaluate plant operating data and results from his grindability test, Fred Bond developed the ""Third Theory of Comminution."" In the process formulae were developed for converting grams per revolutionobtained from grindability tests to work index.The standard feed sizes for the Bond grindability tests are:Rod Mill Test ore crushed to minus 1ll inchBall Mill Test ore crushed to minus 6 mesh (Tyler)The formulae for converting grams per revolution to work index incorporate the 80% passing sizes for the feed to and the product produced in the specific test. Therefore, accurate work indices can be obtained from Bond grindability tests when the feed size is finer than standard. To obtain accurate test results, the ratio of reduction should be greater than 6 to 1."

Jan 1, 1972

By V. L. Ketellapper

This paper discusses the technical issues and stakeholder collaborative processes which resulted in achieving a balance between the reclamation of abandoned mine sites, providing affordable housing, and preservation of open space at the French Gulch Site. Through this process, it was discovered that mine site reclamation would need to be conducted in conjunction with two priorities for community sustainable development: providing affordable housing for locals who work in the resort town of Breckenridge, and open space preservation. It was found that conducting these activities concurrently would result in providing resources necessary to complete mine site reclamation. The first phase of the affordable housing development is almost completed. This development resulted in redevelopment of mining impacted lands and was recognized by the U.S. Environmental Protection Agency (EPA) with a National Smart Growth Award in 2002.Negotiations are also underway to preserve the remaining 1,800 acres of land held by the mining company as open space. This transaction will in turn provide resources to address water quality issues associated with mine discharges.

Jan 1, 2004

By A. Wahab Khair

Coal mining has evolved into extensive use of continuous mining machines for development and production. This has resulted in an increase in dependence on the versatile continuous miners. The present-day continuous miners are powerful in terms of rated power but are still plagued by wear of bits which hinders development and production as the bits have to be continuously changed at regular intervals. Previous attempts to analyze bit wear has been either restricted to the theoretical approach and or laboratory testing. This paper discusses about the overall aspect of bit and drum design for different conditions. Using the laboratory model set up, numerical models and field testing, a new bit and drum design was analyzed to evaluate their performance under different conditions. The results proved that a newer bit design and drum design were successful in limiting the amount of wear as well as improving the performance of the continuous miner and production.

Jan 1, 2008

By A P. Brown

Access arrangements required with landowners and occupiers; relaxation on size of permits; lack of confidentiality for information provided; one-stop shop under RMA, removal of standing; plethora of controls; post-closure; funding for long-term security.

Jan 1, 1997

By R. Flatabø, K-E. Johansen, L. Hunsbedt, P. M. Cowx, J. A. Bustnes

Eramet and Tinfos are two producers of manganese alloys in Norway, which have worked hard for several decades to improve both the internal and external environment. Furnaces producing ferro- and silico- manganese alloys generate large amounts of off-gas that contains substantial amounts of dust, heavy metals and organic by-products. The dust is separated from the gas in venturi scrubbers by washing with water. The water is cleaned and recirculated, and the surplus water coming from moisture in the raw materials, is discharged to the adjacent fjords after further treatment. Emission figures show that the discharge of suspended solids, manganese, zinc and PAH (polycyclic aromatic hydrocarbons) have been reduced substantially over the last three decades as a result of process improvements and installation of state of the art environmental control measures. The two plants were the first world wide to install mercury cleaning of the off-gases from the furnaces. Mercury emission reduction has exceeded 90%. Concerning other environmental issues, such as utilisation of off-gases for energy recovery and chemical purposes, both plants have achieved good results. Major effort in the environmental work has come from the plants themselves, but other players like FFF, The Norwegian Ferroalloy Producers Research Association, and SFT, The Norwegian Pollution Control Authority, have contributed to the achieved results.

Jan 1, 2007