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Sample records for argentina gravel mines

  1. Environmental laws for mining activities in Provincia de San Juan (Argentina), gravel mines exploitation

    Ramirez, M.; Carrascosa, H.

    2007-01-01

    This paper analyses San Juan Province - Argentina prevailing environmental legislation for mining activity and gravel mines. The study focuses the subject from a mining engineering point of view. (author)

  2. Sand and gravel mine operations and reclamation planning using microcomputers

    Ariffin, J.B.

    1990-02-01

    The purpose of this study is to focus on the application of microcomputers, also known as personal computers, in planning for sand and gravel mine operations and reclamation at a site in Story County, Iowa. This site, called the Arrasmith Pit, is operated by Martin Marietta Aggregates, Inc. The Arrasmith site, which encompasses an area of about 25 acres, is a relatively small site for aggregate mining. However, planning for the concurrent mine operation and reclamation program at this site is just as critical as with larger sites and the planning process is the same.

  3. Injury experience in sand and gravel mining, 1991

    1993-10-01

    This Mine Safety and Health Administration (MSHA) informational report reviews in detail the occupational injury and illness experience of sand and gravel mining in the United States for 1991. Data reported by operators of mining establishments concerning work injuries are summarized by work location, accident classification, part of body injured, nature of injury, and occupation. Related information on employment, worktime, and operating activity also is presented. Data reported by independent contractors performing certain work at mining locations are depicted separately in this report. For ease of comparison with other metal and nonmetallic mineral mining industries and with coal mining, summary reference tabulations are included at the end of both the operator and the contractor sections of this report.

  4. Sand and gravel mining: effects on ground water resources in Hancock county, Maine, USA

    Peckenham, John M.; Thornton, Teresa; Whalen, Bill

    2009-01-01

    Based on this preliminary study, existing sand and gravel mining regulations (in Maine, USA) can be inferred to provide some protection to water resources. Sand and gravel deposits are important natural resources that have dual uses: mining for construction material and pumping for drinking water. How the mining of sand and gravel affects aquifers and change aquifer vulnerability to contamination is not well documented. Mining regulations vary greatly by state and local jurisdiction. This study test metrics to measure the effectiveness of mining regulations. The sand and gravel aquifer system studied is covered with former and active gravel pits to nearly 25% of its areal extent. Data from homeowner interviews and field measurements found scant evidence of changes in water quantity. Water quality analyses collected from springs, streams, ponds and wells indicate that the aquifer was vulnerable to contamination by chloride and nitrate. However, water quality changes can not be related directly to mining activities.

  5. Land Use and River Degradation Impact of Sand and Gravel Mining

    Syah, Putra Rizal Ichsan; Hartuti, Purnaweni

    2018-02-01

    Sand and gravel mining is aimed at providing materials for infrastructure development, as well as providing economical source to the miners. However, the impacts of sand and gravel mining could also cause disturbances to ecological balance, since it is closely related to land use change and river degradation, besides causing conflicts in the miners, the government, and the private relationship. Therefore the government regulation and proper supervision are needed to preserve the ecological balance and decreasing the negative impacts of this mining, and therefore guarantee sustainable development.

  6. Channel dynamics and geomorphic resilience in an ephemeral Mediterranean river affected by gravel mining

    Calle, Mikel; Alho, Petteri; Benito, Gerardo

    2017-05-01

    Gravel mining has been a widespread activity in ephemeral rivers worldwide whose long-lasting hydrogeomorphological impacts preclude effective implementation of water and environmental policies. This paper presents a GIS-based method for temporal assessment of morphosedimentary changes in relation to in-channel gravel mining in a typical ephemeral Mediterranean stream, namely the Rambla de la Viuda (eastern Spain). The aims of this work were to identify morphosedimentary changes and responses to human activities and floods, quantify river degradations and analyze factors favoring fluvial recovery for further applications in other rivers. Aerial photographs and LiDAR topography data were studied to analyze geomorphic evolution over the past 70 years along a 7.5-km reach of an ephemeral gravel stream that has been mined intensively since the 1970s. To evaluate changes in the riverbed, we mapped comparable units applying morphological, hydraulic, and stability (based on vegetation density and elevation) criteria to 13 sets of aerial photographs taken from 1946 to 2012. A detailed spatiotemporal analysis of comparable units revealed a 50% reduction in the active section and a 20% increase in stable areas, compared to the conditions observed prior to gravel mining. Instream mining was first observed in 1976 aerial photograph covering already up to 50% of the 1956 riverbed area. River degradation since then was quantified by means of a LiDAR DTM and RTK-GPS measurements, which revealed a 3.5-m incision that had started simultaneously with gravel mining. Climate and land use changes were present but the effects were completely masked by changes produced by instream gravel mining. Therefore, river incision/degradation was triggered by scarcity of sediment and lack of longitudinal sedimentary connection, creating an unbalanced river system that is still adjusting to the present hydrosedimentary conditions.

  7. Plant succession patterns on residual open-pit gravel mines deposits Bogota

    Ricardo A. Mora Goyes

    1999-01-01

    Based on both: the study of composition and structure of plant communities and the analysis of the physico-chemical characteristics of mining wastes, the initial patterns of primary succession were determined. These patterns were present in three deposits of waste material abandoned during 18, 36 and 120 months respectively. Sue materials were originated in open-pit gravel mines located to the south of Bogota (Colombia). This study pretends to contribute to the knowledge of the meehanlsms of ...

  8. Morphological evolution of the Maipo River in central Chile: Influence of instream gravel mining

    Arróspide, Felipe; Mao, Luca; Escauriaza, Cristián

    2018-04-01

    Instream gravel mining is one of the most important causes of channel degradation in South America, specifically in rivers located near large metropolitan areas with rapidly growing cities, where no river management strategies exist. In the western region of the continent, many of these rivers belong to Andean systems, in which significant parts of the watersheds are located in mountain areas at high altitude, with considerable seasonal rainfall variability and steep channel slopes. In these rivers, gravel mining has produced significant incision of the channels with serious physical and ecological consequences, affecting habitats, modifying the supply and transport of sediments, and amplifying the risk to infrastructure in and around the channel during floods. In spite of the degraded conditions of many channels, no quantitative studies of the geomorphic impacts of gravel mining have been carried out in the region, mostly because of the insufficient and sparse data available. In this investigation we perform an analysis of the morphodynamic evolution in a section of the Maipo River in the metropolitan region of Santiago, Chile. This river is economically the most important in the country, as it provides drinking and irrigation water to urban and rural areas, is utilized by the energy generation industry, and runs along and below critical infrastructure. We have collected and analyzed data from 1954 to 2015, during which the city population increased by more than 5 million inhabitants whose presence accelerated land use changes. The analysis shows a rapid morphological evolution of the channel where in 31 years effects such as: river sections showing incision of up to 20 m, an increase of the area affected by gravel mining from 86.62 to 368.13 ha, and a net erosion volume of 39.4 million m3 can be observed. This work yields quantitative information on the consequences of gravel mining in the Maipo River, providing the necessary data to develop an integrated

  9. Instream sand and gravel mining: Environmental issues and regulatory process in the United States

    Meador, M.R.; Layher, A.O.

    1998-01-01

    Sand and gravel are widely used throughout the U.S. construction industry, but their extraction can significantly affect the physical, chemical, and biological characteristics of mined streams. Fisheries biologists often find themselves involved in the complex environmental and regulatory issues related to instream sand and gravel mining. This paper provides an overview of information presented in a symposium held at the 1997 midyear meeting of the Southern Division of the American Fisheries Society in San Antonio, Texas, to discuss environmental issues and regulatory procedures related to instream mining. Conclusions from the symposium suggest that complex physicochemical and biotic responses to disturbance such as channel incision and alteration of riparian vegetation ultimately determine the effects of instream mining. An understanding of geomorphic processes can provide insight into the effects of mining operations on stream function, and multidisciplinary empirical studies are needed to determine the relative effects of mining versus other natural and human-induced stream alterations. Mining regulations often result in a confusing regulatory process complicated, for example, by the role of the U.S. Army Corps of Engineers, which has undergone numerous changes and remains unclear. Dialogue among scientists, miners, and regulators can provide an important first step toward developing a plan that integrates biology and politics to protect aquatic resources.

  10. Plant succession patterns on residual open-pit gravel mines deposits Bogota

    Ricardo A. Mora Goyes

    1999-07-01

    Full Text Available Based on both: the study of composition and structure of plant communities and the analysis of the physico-chemical characteristics of mining wastes, the initial patterns of primary succession were determined. These patterns were present in three deposits of waste material abandoned during 18, 36 and 120 months respectively. Sue materials were originated in open-pit gravel mines located to the south of Bogota (Colombia. This study pretends to contribute to the knowledge of the meehanlsms of natural restauration of tropical ecosystems subjected to man-borne degradation.

  11. Fabrication of gravel for concrete in brown-coal mining. The gravel works at Inden; Betonkiesherstellung im Braunkohlentagebau - Das Kieswerk Inden

    Bertrams, H.J. [Rheinbraun AG, Abt. Tagebau- und Landschaftsplanung, Koeln (Germany)

    1995-01-01

    The brown-coal open-pit mine is operated by Rheinbraun AG, a Cologne-based company. The mining process offers the possibility to separate gravel and sand from the overburden for marketing, unless they are indispensable for reclaiming the open-pit mine. This combination of raw material production particularly prevents additional landscape consumption by separate gravel dredging and spares the population of an overproportionately densely populated region further inconveniences. Moreover, it helps to save resources. (orig./MSK) [Deutsch] Die Braunkohlengewinnung erfolgt durch die in Koeln ansaessige Rheinbraun AG in Tagebauen. Dabei ergibt sich die Moeglichkeit, im Abraum befindliche Kiese und Sande auszusortieren und dem Markt zuzufuehren, soweit sie nicht zwingend zur Wiedernutzbarmachung des Tagebaus verwendet werden muessen. Durch die Buendelung der Rohstoffgewinnung wird insbesondere der Landschaftsverbrauch durch gesonderte Abgrabungen ausserhalb des Tagebaus und damit verbundene Belastungen der Bevoelkerung in einer ueberdurchschnittlich dicht besiedelten Region verringert. Sie traegt ebenfalls zur Ressourcenschonung bei. (orig./MSK)

  12. EVALUATION OF THE INITIAL TREE COMMUNITY ESTABBLISHED ON A GRAVEL MINE IN THE BRAZILIAN FEDERAL DISTRICT

    Raquel Álvares Leão

    2005-05-01

    Full Text Available Mining activities for urbanization purposes have been practiced in the BrazilianFederal District for the last fifty years. Exploitation of sand, clay, stones, calcareous rocks,and gravel deposits resulted in 0.6% of the territory degraded by mining. Deposits explored inthe last ten years have been reclaimed as demanded by local laws.The natural restoration of areas degraded by mining explotation is unpraticable,because the seed-bed and seedlings-bed is very injuried. Also the superficial layers of soil aretaken off, causing loss of microorganism like fungi, which contributes for environmental’squality improvement for the vegetation reestablishment (Vargas & Hungria, 1997.Fortunatelly, environmental laws oblige miners to replace these superficial layers of soil(CREA-DF Cursos, 2004.The recovering of a degradaded area doesn’t necessarily mean restoration. Restorationonly happens when the damage is minimal, for example, a glade opened by the death of a tree(Fonseca et al., 2001. When an area is hardly damaged, the vegetal climax community,resulting from secondary succession, will never be the same as the one standed there before(CREA-DF Cursos, 2004; Fonseca et al., 2001. In the case of areas degraded by mining,human intervention is necessary, because the vegetation has lost its resilience, and is not ableto commence a secondary succession by itself.

  13. Sustainability of new uranium mining projects in Argentina

    Navarra, P.R.

    2002-01-01

    The regulatory framework issued in the 1994-1995 period, connected mining activities in Argentina with international good environmental practices. Agreements between National Government and Provinces allow the application of the regulations, while Act No 24.585, the milestone about the matter, establishes the steps for the approval of the Report of Environmental Impact, on successive stages of the project. Specifically for uranium mining and milling, the assessment of the radiological protection aspects of the planned activities is assigned to the Nuclear Regulatory Authority. The National Atomic Energy Commission is at present carrying out two uranium mining projects, that involve the Sierra Pintada and Cerro Solo deposits. The goal of them is restart uranium production in the country in the medium term, by lowing the gap between indigenous and market uranium prices. The first one consists in updating the feasibility study of the, at present inactive, Sierra Pintada Production Center (Mendoza Province). Studies for improving the mining and treatment methods are performed in the project, co-ordinately with the investigation and forecast of mining waste and processing tailings management. Besides, the procedures will be determined taking into account the methodology to be applied when getting the closure stage, about the existing waste and tailings. Development of the Sierra de Pichinan District, Chubut Province (U-Mo), is the objective of the second project. It is remarkable that about Cerro Solo, the main ore deposit belonging to this area, at the prefeasibility stage, CNEA is currently encouraging private investment through a bidding process. Environmental studies are an important aspect of the activities carried out and planned in the area. As a conclusion, with regard uranium mining and milling activities in Argentina, the regulations and environmental technical-scientific knowledge are becoming friendly with the sustainable practice. (author)

  14. Radiological environmental monitoring around the mining sites in Argentina

    Quintana, Eduardo E.; Gomez, Juan C.; Palacios, Miguel A.

    2004-01-01

    The uranium mining industry began its development in Argentina in the fifties. Since then, several installations have operated as uranium underground mining until late seventies, when that mines were closed. Since then, open pit exploitation has been used. Milling facilities were installed in the mining areas or close to them. The environmental radiological surveillance and the impact assessment presented in this work are referred to the uranium ore mining and milling plants Tonco, in Salta province; Pichinan, in Chubut province; San Rafael and Malargue, in Mendoza province; Los Gigantes, in Cordoba province; La Estela, in San Luis province and Los Colorados in La Rioja province. The environmental radiological surveillance programme results carried out from the beginning of the operations are presented and include uranium and radium concentrations in surface waters and sediments. The results obtained in waters upstream and downstream the uranium mining complexes are compared and no significant differences were observed. Moreover, taking into consideration the critical exposition pathways of the population living in the area, no significant levels of exposition were observed. (author)

  15. Argentina

    Masters, R.

    1997-01-01

    This article provides information on the energy resources, government, electricity supply, nuclear industry and fuel cycle of Argentina. About 12% of electric power produced is generated from nuclear power plants. The operating capacity, history and partial privatisation of the nuclear industry are covered, and fuel cycle facilities described. These include uranium mining and processing, enrichment, fuel fabrication and heavy water production. (UK)

  16. Water management methodologies from mining and milling activities in Argentina

    Asenjo, A.

    2006-01-01

    Mining and Milling activities have been developed in Argentina in several provinces, in order to obtain uranium concentrate. As a result of milling process and mining exploitation, contaminated water remain accumulated in several sites. Methodologies to treat the contaminated water from the different places has been evaluated, at laboratory scale. At Los Gigantes Site, effluents from process containing U, Ra, Mn and NH 4 + , are accumulated in a dam. Precipitation using lime and barium chloride was tested to remove impurities in the effluent. From the same place, contaminated liquid from seepage of tailing containing U and Ra was treated using different permeable reactive barriers (PRB). Some materials, such as zeolite, montmorillonite and iron fine grained (Fe 0 ), to be study as a permeable reactive barrier (PRB), were tested to treat seepage. Glass column 100 cc of capacity, were used to performed the tests. At Sierra Pintada Site, water from mine containing U, Ra and As, are accumulated in a open pit. Anionic resin Amberlite IR 400 to remove uranium, and precipitation using barium chloride and iron sulphate to remove radium and arsenic, were tested to treat water from the open pits. Glass column resin 1000 cc of capacity, and a agitated tank 25 liter of capacity for precipitation, were used to performed the test. Cationic resin, Amberlite IR 120, was tested too, in order to remove radium from water from mine. (author)

  17. Towards an increase of flash flood geomorphic effects due to gravel mining and ground subsidence in Nogalte stream (Murcia, SE Spain

    J. A. Ortega-Becerril

    2016-10-01

    Full Text Available Transition from endorheic alluvial fan environments to well-channelized fluvial systems in natural conditions may occur in response to base-level fluctuations. However, human-induced changes in semi-arid regions can also be responsible for similar unforeseen modifications. Our results confirm that in-channel gravel mining and aquifer overexploitation over the last 50 years in the case study area have changed the natural stability of the Nogalte stream and, as a result, its geomorphic parameters including channel depth and longitudinal profile have begun to adapt to the new situation. Using interferometric synthetic aperture radar (InSAR data we obtain maximum values for ground subsidence in the Upper Guadalentín Basin of  ∼ 10 cm yr−1 for the period 2003–2010. In this context of a lowered base level, the river is changing its natural flood model to a more powerful one. A comparison of the 1973 flood event, the most dramatic flood event ever recorded in the area, with the 2012 event, where there was a similar discharge but a sediment load deficit, reveals greater changes and a new flooding pattern and extension. In-channel gravel mining may be responsible for significant local changes in channel incision and profile. This, together with the collateral effects of aquifer overexploitation, can favour increased river velocity and stream power, which intensify the consequences of the flooding. The results obtained here clearly demonstrate an existing transition from the former alluvial pattern to a confined fluvial trend, which may become more pronounced in the future due to the time lag between the drop in aquifer level and ground subsidence, and introduce a new scenario to be taken into consideration in future natural hazard planning in this area.

  18. Argentina.

    1986-06-01

    This discussion of Argentina covers geography, the people, history and political conditions, government, economy, foreign relations, and relations between the US and Argentina. In 1985, the population of Argentina was estimated to be 30.6 million with an estimated annual growth rate of 1.5%. The infant mortality rate is 34.1/1000, and life expectancy is 70.2 years. Argentina, which shares land borders with Bolivia, Brazil, Chile, Paraguay, and Uruguay, is bounded by the Atlantic and the Antarctic Oceans. Descendants of Italian and Spanish immigrants predominate in Argentina, but many trace their origins to British and West and East European ancestors. In recent years, there has been a substantial influx of immigrants from neighboring Latin American countries. The native Indian population, estimated to be 50,000, is concentrated in the peripheral provinces of the north, northwest, and south. What is now Argentina was discovered in 1516 by the Spanish navigator Juan de Solia. The formal declaration of independence from Spain was made on July 9, 1816. In the late 19th century, 2 forces worked to create the modern Argentine nation: the introduction of modern agricultural techniques and the integration of Argentina into the world economy. Argentina has impressive human and natural resources, but political conflict and uneven economic performance since World War II have impeded full realization of its considerable potential. Yet, it is one of the wealthiest countries in Latin America. Among the reasons for the military coup of March 1976 was the deteriorating economy, caused by declining production and rampant inflation. Under the leadership of the Minister of the Economy, the military government focused attention on those immediate problems, and, in 1978, embarked on a new development strategy focusing on the establishment of a free market economy. There was little improvement in the economy, and a new economic plan was introduced in 1985 which has capped inflation by

  19. Measurement of radon concentration in old metalliferous mines in San Luis, Argentina

    Anjos, Roberto M.; Lacerda, Tiago; Rosas, Juan P. de [Instituto de Fisica, Universidade Federal Fluminense, Av. Gal Milton Tavares de Souza, s/no, Gragoata, 24210-346, Niteroi, RJ (Brazil); Da Silva, Almy A.R. [Instituto de Fisica, Universidade Federal Fluminense, Av. Gal Milton Tavares de Souza, s/no, Gragoata, 24210-346, Niteroi, RJ (Brazil); Instituto de Fisica, Universidade de Sao Paulo, P. O. Box 66318, 05314-970, Sao Paulo, SP (Brazil); Rizzotto, Marcos; Valladares, Diego L.; Velasco, Hugo [GEA, Instituto de Matematica Aplicada San Luis (IMASL), Universidad Nacional de San Luis, Consejo Nacional de Investigaciones Cientificas y Tecnicas, Ej. de los Andes 950, D5700HHW San Luis (Argentina); Yoshimura, Elisabeth M. [Instituto de Fisica, Universidade de Sao Paulo, P. O. Box 66318, 05314-970, Sao Paulo, SP (Brazil)

    2014-07-01

    Radon levels in two old mines in San Luis, Argentina, were measured and analyzed. La Carolina gold mine and Los Condores tungsten mine are today used as tourism mines. CR-39 nuclear track detectors were used for this purpose. Measurements were performed during both winter and summer seasons. The findings show that in these environments, significant radon concentrations are subject to large seasonal fluctuations, due to the strong dependence on natural ventilation with the outside temperature variations. For both mines, high concentration values of {sup 222}Rn were observed in summer and low values in winter; with an extreme ratio of 2.5 times between summer and winter seasons for Los Condores mine. The radiation dose and environmental health risk of {sup 222}Rn concentrations to both guides and visitors were estimated for both seasons and compared with dose and action level values recommended by the International Commission on Radiological Protection (ICRP). The radon contribution to the effective dose rate for visitors has been previously assessed for the warm season. The values are 0.38±0.07 mSv y{sup -1} and 0.05±0.02 mSv y{sup -1} for La Carolina and Los Condores, respectively. These values were obtained assuming an accumulated annual time underground of 20 h. For the guides these values are 11±2 mSv y{sup -1} and 1.45±0.5 mSv y{sup -1} for La Carolina and Los Condores, respectively, assuming an accumulated annual time underground of 600 h. The occupational dose rate limit suggested by the ICRP is 20 mSv y{sup -1}. As these values indicate the dose is an order of magnitude lower in Los Condores than La Carolina mine. This is because this mine, due to its characteristics, is more ventilated than La Carolina mine. This is important because actions can be taken to lower the radon accumulation in La Carolina gold mine, for example by opening new ducts to increase air circulation. Finally, in this work, seasonal variations of the dose rate are assessed and

  20. Argentina

    2001-04-01

    This economical study summarizes the energy situation of Argentina: energy institutions and policy, energy companies (oil, electricity, gas, coal), energy supplies (resources, power production, petroleum, natural gas), prices and tariffs, consumption, economical stakes and perspectives (investments, agreements, projects). Energy data for the 1971-1999 period are summarized in graphs and tables. (J.S.)

  1. Argentina

    1999-09-01

    This report presents a brief overview of the socio-economic, energy and environmental context in which climate change mitigation actions in Argentina shall be inserted. To that end, the dynamic of the Argentine economic development, its influence on the energy system and environmental impacts is summarised. From the environmental standpoint, emphasis shall only be made on the impact of economic development patterns and energy policies on GHG emission. (au) 73 refs.

  2. Argentina

    Tanis, S.; Ramberg, B.

    1990-01-01

    Argentina has embarked on an ambitious domestic nuclear research and energy program. The venture promises to provide the nation with the infrastructure to play an important role in the nuclear export market in the years ahead. Buenos Aires built its program on a foundation of international support and assistance that overlay an emerging sophisticated industrial and scientific establishment. The foreign contribution sensitized Argentina to opportunities in the global market. This paper reports that Argentina operates two heavy-water/natural uranium reactors, Atucha I and Embalse. Producing, respectively, 320 MW(e) and 600 MW(e), they supply roughly 10 percent of the country's electricity. With a capacity factor of 84 percent, Atucha I is among the best operated plants in the world. Plans call for a third, 745 MW(e) power plant, Atucha II, to go on line in the early 1990s. During this period, construction also may begin on three 300 MW(e) plants, although the country's foreign indebtedness plus cost overruns in earlier construction will place a heavy burden on these plans

  3. The dispute over the social license for mining projects in La Rioja, Argentina

    Mariana Sola Álvarez

    2013-11-01

    Full Text Available Since the beginning of this century, projects of transnational corporations design to extract -in a mega scale- gold, silver, copper, and molybdenum are back to interrogate Famatina Valley, located in the northwest of Argentina, in the province of La Rioja. The dispute that is generated around the "social license" of mining projects highlights features of policy matrix and local government backing for extractive activities. At the same time illustrates the content and the potentiality of social resistance. The power of veto from a network of neighbors assemblies and a highly mobilized community in critical moments of the conflict is framed in a process of resistance to mercantilization of commons that travels through Latin America.

  4. A real-time approach toward the chemical quality control of rock material (Case study: Gravel mines in Semnan, Iran

    Behzad Tokhmechi

    2016-06-01

    Full Text Available The quality of concrete is highly dependent on the characteristics of its aggregate, such as the size, minerals, and their chemical properties. Even a small amount of impurities, such as hydrated sulfates, chlorine (salt, and acidic pH of the rock material, can adversely affect the quality of the concrete. Thus, many national codes and standards are developed for testing, selecting, and employing the rock materials in concrete. For instance, Iranian standards 446, 449, 1702, 4978, 4984, 7174, and 86721 are currently serving this purpose. In the present research, a new real-time system was developed in order to replace the customary chemical analysis and size distribution tests. 20 samples were taken from two mines, selected by the Building Material Committee of Semnan Province, in order to determine the dissolved chlorine and sulfate, pH, density as well as size distribution. The new system is constituted of hydraulic jacks and a reservoir, designed to take samples from the conveyer in given time intervals. The samples were washed with distilled water and real-time analyses of dissolved chlorine and pH were performed. The results showed 85% agreement with the results from laboratory analyses. The correct classification rate (CCR was 92% for 13 samples.

  5. ESTUDIO ARQUEOHISTÓRICO DEL REGISTRO VÍTREO EN SITIOS MINEROS (MENDOZA, ARGENTINA (Archaeohistorical Study of the Vitreous Record in Mining Sites (Mendoza, Argentina

    Osvaldo Sironi

    2017-06-01

    Full Text Available Se presentan los resultados de los análisis de los registros vítreos de los sitios Minas Paramillos Sur y Mina La Atala, localizados en la Reserva Natural Villavicencio y Divisadero Largo. A partir del conocimiento de la materialidad cultural vítrea de esta región, se evidencian patrones de consumo vinculados a diversos tipos de bebidas y productos medicinales entre la clase trabajadora minera de la Precordillera de Mendoza (Argentina. ENGLISH: Results of the analysis of the vitreous record from Minas Paramillos Sur and Mina La Atala are presented. These sites are located in the Villavicencio and Divisadero Largo natural reserves. Knowledge of the vitreous cultural material of this region allows us to show consumption patterns of various types of beverages and medicines among the mining working class of the Mendoza Precordillera, Argentina.

  6. Argentina

    Anon.

    1992-01-01

    This paper reports that like so many other countries, Argentina is in the throes of privatization and restructuring of its economic programs. This has had a direct effect on the LPG industry. Argentina is a country with many natural resources. However, natural gas and crude, while present, are not in abundance. Imports of these and their associated products are needed to satisfy the growing need of the population from time to time. This is especially true with LPGs. Production of the fuel averages about 1 million tons, not enough to satisfy internal needs in the winter but enough to permit some exports in the summer to nearby Brazil. The Country's Congress approved a plan to sell-off or lease parts of the natural gas distribution network and other businesses of Gas del Estado. Subsequent new legislation has called for ten new natural gas distribution zones. Included in the sell-off is the company's propane distribution division. What is left of Gas del Estado and YPF will become a corporation in the true sense of the word. Stocks in YPF are to be sold to the public

  7. Uranium mining and milling sites in Argentina: environmental radiological monitoring (1980-1994)

    Bomben, A.M.; Gomez, J.C.; Oliveira, A.A.

    1995-01-01

    Environmental radiological monitoring in the vicinity of uranium mining and milling plants in Argentina is performed on a routine basis, in order to assess the possibility of significant environmental contamination due to uranium mill wastes and mill tailings of plants still operating or those where the exploitation have concluded. Dissolved natural uranium and 226 Ra concentrations in surface waters are measured in samples taken from rivers near the mills, according to a special monitoring plan set up for each facility. In addition, 222 Rn emanation rates from ore tailings are measured at times. In this paper the environmental radiological monitoring program results obtained for the 1980-1994 period are shown. From the data analyses it can be concluded that there are not significant differences for the concentrations of the radionuclides of interest, between the surface water samples taken from river location above and below the plants discharge points. Besides, no significant exposure results for the population living in the surrounding areas due to the uranium mining and milling plants operation or their wastes. (author). 2 refs., 5 figs

  8. NEW RECORDS AND ICHNOSPECIES OF LINEAR LEAF MINES FROM THE LATE MIOCENE-PLIOCENE FROM ARGENTINA AND THE ESTABLISHMENT OF LEAF-MINING ICHNOTAXOBASES

    JUAN M. ROBLEDO

    2016-10-01

    Full Text Available The ichnospecies Cuniculonomus parallelus Givulescu 1984 and Stigmellites serpentina Kozlov 1988 are recorded for the first time in Argentina and the new ichnospecies Cuniculonomus saltensis isp. nov., Stigmellites vitatus isp. nov. and Stigmellites pervenae isp. nov are defined from two Miocene localities: Peñas Blancas and Quebrada del Horno, from northwestern Argentina. A set of characters to identify fossil linear mines is provided as well as five ichnotaxobases to differentiate the ichnogenera Cuniculonomus, Stigmellites and Phytomyzites. Two ichnospecies are now revised and included in Phytomyzites: P. arcuata (Krassilov 2008a comb. nov. (Ophionoma and P. crucitracta (Krassilov 2008a comb. nov. (Troponoma. Finally, a review of fossil record of linear mines is provided.

  9. Argentina.

    1993-02-01

    Background notes on Argentina provide a profile of the geography, selected demographic features, government and economic conditions. Descriptive text includes a discussion of the people, their history and political conditions, the government and officials, the state of the economy, their defense, foreign relations, and relations with the US. The 1992 estimated population was about 33 million of whom 97% are European (mostly Spanish and Italian). Religions represented are Roman Catholic (92%), Protestant (2%), Jewish (2%), and other (4%). Adult literacy is 95%. 36% are engaged in industry and commerce, 20% in services, 19% in agriculture, 6% in transport and communications, and 19% other. Per capita gross domestic product was $4,500. There are only 50,000 native Indians remaining in peripheral provinces. The population enjoys a high standard of living and a low growth rate. The country was shaped by dominant forces: modern agricultural techniques and the integration of the country into the world economy. Foreign investment aided the economic revolution. Conservative and radical rule has swung the country back and forth politically since 1916. Colonel Juan Domingo Peron led a successful military coup in 1943 and was elected in 1946. Policies were instituted to give a greater voice to the working class, and with the influences of his wife, women's groups. In 1955, he was ousted by the military, which failed to revive the economy and quiet increasing terrorism. After a number of difficult elections, Peron was reinstated as president in 1973. Extremists on the left and right threatened public order; the military as a consequence imprisoned persons indefinitely. Peron's wife succeeded him after his death, but was removed from office in the military coup of 1976. Basic human rights were violated during this period. By 1983, a fair election was held and support increased for a democratic system. In 1989, Carlos Saul Menem, a Peronist candidate, won and established

  10. Argentina

    G. Benedetti

    2007-01-01

    Full Text Available El presente trabajo tiene como objetivo realizar un diagnóstico ambiental de un sector de la ciudad de Bahía Blanca, Argentina basado en el arbolado urbano de alineación. El arbolado constituye un componente fundamental de los paisajes artifi ciales ya que contribuye al aumento del confort y al mejoramiento de la calidad del medio. En este sentido, actúa como un factor moderador de las condiciones climáticas, la contaminación y la salud de la población. El municipio de la ciudad de Bahía Blanca tiene como proyecto la realización de inventarios del arbolado en los distintos barrios, para lograr optimizar la relación entre la cantidad de ejemplares arbóreos y la densidad poblacional. Es importante considerar la variedad de ejemplares en función del uso del suelo y de las características ambientales de cada sector. Por lo tanto, este trabajo presenta un diseño metodológico para la elaboración del plano verde de la ciudad.

  11. Integrated mined-area reclamation and land use planning. Volume 3A. A case study of surface mining and reclamation planning: South Boulder Creek Park Project, Sand and Gravel Operations, Boulder, Colorado

    Lewis, L R; Perry, A O; LaFevers, J R

    1977-02-01

    This case study details reclamation planning for the Flatiron Companies' South Boulder Creek Park Project in Boulder, Colorado. The site contains a deposit of high-quality sand and gravel considered to be one of the best and largest known deposits of aggregate materials in the Front Range area. The aggregate deposit is located in a highly visible site just off the Denver-Boulder Turnpike at the entrance to the city from Denver, and adjacent to a residential portion of the city. In order to make maximum use of pre-mining planning, as a tool for resolving a conflict over the company's proposed operation, an extensive cooperative planning effort was initiated. This included the preparation of an environmental impact assessment, numerous public hearings, operating and reclamation plan review by city authorities, annexation of the site to the city, and the granting of a scenic easement on the property to the city for the development of a regional recreation park. A suite of contractual agreements was worked out among Flatiron Companies, the City of Boulder, the Colorado Open Lands Foundation, and the Federal Bureau of Outdoor Recreation. The purpose of this case study is to allow the planner to gain insight into the procedures, possibilities, and constraints involved in premining planning in a cooperative situation.

  12. Reconditioning contaminated gravel

    Walsh, H.; Bowers, J.S.; Cadwell, K.

    1995-02-01

    Lawrence Livermore National Laboratory (LLNL) has developed a portable screening system that will recondition radioactively contaminated gravel in the field. The separation technique employed by this system removes dirt, contaminated debris, and other fine particles from gravel. At LLNL, gravel is used in conjunction with the experimental testing of explosives to reduce shock wave propagation. The gravel surrounds the experimental device and buffers the energy generated from the explosion. During an explosion, some of the gravel is broken down into small particles and mixed with contaminants. Contaminants in the used gravel originate from metal sheathing and other parts comprising, the experimental device. These contaminants may consist of radionuclides and metals that are considered hazardous by the State of California when disposed. This paper describes the process that conveys contaminated material into the screener system, sprays the material with recycled water or other mild cleaning chemicals, and separates particles based on size. Particles greater than a specified size are discharged out of the screener separator and recycled back into use, thereby reducing the amount of mixed waste generated and minimizing the need for new gravel. The fines or silt are flushed out of the separator with the water and are removed from the water and consolidated into a drum with the use of a hydrocyclone separator and drum decant system. Because the water in the spray system is recycled, minimal makeup water is needed. The system monitors pH and total dissolved solids

  13. Sand and Gravel Deposits

    Vermont Center for Geographic Information — This dataset is a statewide polygon coverage of sand, gravel, and stone resources. This database includes the best data available from the VT Agency of Natural...

  14. Sand and Gravel Operations

    Department of Homeland Security — This map layer includes sand and gravel operations in the United States. These data were obtained from information reported voluntarily to the USGS by the aggregate...

  15. The culture of the workplace as a resource for the leisure culture: tourism activation of heritage industrial-mining in Argentina

    Aldo Ramos Schenck

    2015-09-01

    Full Text Available This paper develops the theme of the use of cultural resources produced by the activities mining-industrial and its revaluation for tourism and recreation, expressing the types of projects to be able to perform it and the associated problems. There is an analysis for the case of Argentina and the potentialities and difficulties for tourist-recreation activation of some of the existing resources.

  16. Pebble breakage in gravel

    Tuitz, C.

    2012-01-01

    The spatial clustering of broken pebbles in gravel layers of a Miocene sedimentary succession was investigated. Field observations suggested that the occurrence of broken pebbles could be related with gravel hosted shear deformation bands, which were the result of extensional regional deformation. Several different methods were used in this work to elucidate these observations. These methods include basic field work, measurements of physical pebble and gravel properties and, the application of different numerical modelling schemes. In particular, the finite element method in 2D and the discrete element method in 2D and 3D were used in order to quantify mechanisms of pebble deformation. The main objective of this work was to identify potential mechanisms that control particle breakage in fluvial gravel, which could explain the clustered spatial distribution of broken pebbles. The results of 2D finite element stress analysis indicated that the breakage load of differently located and oriented diametrical loading axes on a pebble varies and, that the weakest loading configuration coincides with the smallest principal axis of the pebble. The 3D discrete element method was applied to study the contact load distribution on pebbles in gravel deposits and the influence of different degrees of particle imbrication and orientation. The results showed that an increase of the number of imbricated particles leads to a significant load transfer from the rim to the centre of the oblate sides of the ellipsoidal particles. The findings of these pebble-scale investigations provided the basis for outcropscale modelling, where simulated gravel layers were subjected to layer-parallel extension. These outcrop-scale models revealed the existence of a particle breakage enhancing mechanism that becomes active during early stages of shear band formation. The interaction of such shear bands with the less deformed host material results in particle stress concentrations and subsequently

  17. The gravel sand transition in a disturbed catchment

    Knighton, A. David

    1999-03-01

    More than 40 million cubic metres of mining waste were supplied to the Ringarooma River between 1875 and 1984, leading to successive phases of aggradation and degradation. The natural bed material is gravel but, given the volume of introduced load and the fact that much of the input was less than 5 mm in diameter, the size composition of the bed changed from gravel to sand during the phase of downstream progressive aggradation. A very sharp gravel-sand transition developed in which median grain size decreased from over 30 mm to under 3 mm in less than 500 m. With upstream supplies of mining debris becoming depleted first, degradation followed the same downstream progressive pattern as aggradation, causing the transition to migrate downstream. By 1984, the river could be regarded as a series of zones, each characterized by a particular bed condition: a natural cobble-gravel bed, unaffected by mining inputs (0-32 km); pre-disturbance bed re-exposed by degradation over 35-40 years (32-53 km); sandy substrate with a gravel armour produced by differential transport during degradation (53-65 km); sand dominated but with developing surface patches of coarser material (65-75 km); sandy bed reflecting the size composition of the original mining input (75-118 km). Although the gravel-sand transition itself is sharp, the transitional zone is lengthy (53-75 km). As degradation continues, the gravel-sand transition is expected to progress downstream but it has remained in a stable position for 12 years. Indeed, two major floods during the period released large quantities of sand from the sub-armour layer and newly-formed banks of mine tailings, causing fining both above and below the transition. Surface grain size is an adjustable component in the transitional zone as the river strives to recover from a major anthropogenic disturbance.

  18. Gravel roads management : volume 1, gravel roads management.

    2010-10-01

    This report establishes procedures for managing dirt and gravel roads, with a primary focus on smaller agencies, such as Wyoming counties, that must manage their roads with very limited resources. The report strives, first, to guide and assist smalle...

  19. Gravel roads management : volume 2, gravel roads management : implementation guide.

    2011-10-01

    This report establishes procedures for managing dirt and gravel roads, with a primary focus on smaller agencies, such as Wyoming counties, that must manage their roads with very limited resources. The report strives, first, to guide and assist smalle...

  20. Gravel roads management : volume 3, gravel roads management : programming guide.

    2010-10-01

    This report establishes procedures for managing dirt and gravel roads, with a primary focus on smaller agencies, such as Wyoming counties, that must manage their roads with very limited resources. The report strives, first, to guide and assist smalle...

  1. Turbidity removal: Gravel and charcoal as roughing filtration media

    Josiah A. Adeyemo

    2010-10-01

    Full Text Available Roughing filtration is an important pre-treatment process for wastewater, because it efficiently separates fine solid particles over prolonged periods, without the addition of chemicals. For this study, a pilot plant was designed at Delmas Coal Mine in the Mpumalanga province of South Africa. The design and sizing of the pilot plant was guided by Wegelin’s design criteria. Gravel was used as a control medium because it is one of the most commonly used roughing filter media and because it was used in developing the criteria. We compared the performance of gravel as a filter medium to that of another locally available material, charcoal, for the removal of turbidity in wastewater. The pilot plant was monitored continuously for 90 days from commissioning until the end of the project. The overall performance of the roughing filter in turbidity removal, using gravel or charcoal, was considered efficient for the pre-treatment of waste water. Charcoal performed slightly better than gravel as a filter medium for the removal of turbidity, possibly because charcoal has a slightly higher specific surface area and porosity than gravel, which could enhance sedimentation and other filtration processes, such as adsorption, respectively.

  2. Gravel Roads: Maintenance and Design Manual

    This manual was developed with a major emphasis on the maintenance of gravel roads, including some basic design elements. The purpose of the manual is to provide clear and helpful information for doing a better job of maintaining gravel roads.

  3. Mining

    Khairullah Khan

    2014-09-01

    Full Text Available Opinion mining is an interesting area of research because of its applications in various fields. Collecting opinions of people about products and about social and political events and problems through the Web is becoming increasingly popular every day. The opinions of users are helpful for the public and for stakeholders when making certain decisions. Opinion mining is a way to retrieve information through search engines, Web blogs and social networks. Because of the huge number of reviews in the form of unstructured text, it is impossible to summarize the information manually. Accordingly, efficient computational methods are needed for mining and summarizing the reviews from corpuses and Web documents. This study presents a systematic literature survey regarding the computational techniques, models and algorithms for mining opinion components from unstructured reviews.

  4. Shrinkage Properties of Cement Stabilized Gravel

    Lund, Mia Schou Møller; Hansen, Kurt Kielsgaard

    2014-01-01

    Cement stabilized gravel is an attractive material in road construction because its strength prop-erties are accommodating the increasingly higher requirements to the bearing capacity of a base course. However, reflection cracking of cement stabilized gravel is a major concern. In this pa...

  5. Stabilization of gravel deposits using microorganisms

    Van der Star, W.R.L.; Van Wijngaarden, W.K.; Van Paassen, L.A.; Van Baalen, L.R.; Zwieten, G.

    2011-01-01

    One of the techniques used for the construction of underground infrastructure is horizontal directional drilling (HDD). This trenchless method is complicated when crossing gravel deposits as a borehole in coarse gravel tends to collapse, causing the drill pipe to get stuck or the failure of

  6. Design and maintenance of subsurface gravel wetlands.

    2015-02-01

    This report summarizes the University of New Hampshire Stormwater Center (UNHSC) evaluation of : a review of Subsurface Gravel Wetlands design and specifications used by the New Hampshire : Department of Transportation (NHDOT or Department). : Subsur...

  7. 76 FR 6110 - Mine Safety Disclosure

    2011-02-03

    .... Paper Comments Send paper comments in triplicate to Elizabeth M. Murphy, Secretary, Securities and.... \\2\\ See, e.g., National Mining Association (January 3, 2011); National Stone, Sand & Gravel...

  8. Review of South American mines

    Anon.

    1984-01-01

    A general overview is presented of the mining activity and plans for South America. The countries which are presented are Columbia, Argentina, Brazil, Venezuela, Chile, Peru, and Bolivia. The products of the mines include coal, bauxite, gold, iron, uranium, copper and numerous other minor materials. A discussion of current production, support and processing facilities, and mining strategies is also given

  9. Large Mines and the Community

    Latin America: costs and benefits of the mining operations ...... in Argentina and Venezuela reached 30 percent, Peru 38 percent and Mexico between 35 .... childbirth facilities, an isolation ward, and a laboratory for the detection of tuberculosis.

  10. Incipient motion of gravel and coal beds

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    2. 1Department of Civil Engineering, Indian Institute of Technology, ... the particle size distribution curve following the relationship by Christensen .... where f = friction factor, ρ = mass density of fluid, and V = mean velocity of flow. .... for the incipient motion of gravel and coal beds have been represented by simple empirical.

  11. Occupational exposure to radon and natural gamma radiation in the La Carolina, a former gold mine in San Luis Province, Argentina

    Anjos, R.M.; Umisedo, N.; Silva, A.A.R. da; Estellita, L.; Rizzotto, M.; Yoshimura, E.M.; Velasco, H.; Santos, A.M.A.

    2010-01-01

    Radon and gamma radiation level measurements were carried out inside the La Carolina mine, one of the oldest gold mining camps of southern South America, which is open for touristic visits nowadays. CR-39 track-etch detectors and thermoluminescent dosimeters of natural CaF 2 and LiF TLD-100 were exposed at 14 points along the mine tunnels in order to estimate the mean 222 Rn concentration and the ambient dose equivalent during the summer season (November 2008 to February 2009). The values for the 222 Rn concentration at each monitoring site ranged from 1.8 ± 0.1 kBq m -3 to 6.0 ± 0.5 kBq m -3 , with a mean value of 4.8 kBq m -3 , indicating that these measurements exceed in about three times the upper action level recommended by ICRP for workplaces. The correlations between radon and gamma radiation levels inside the mine were also investigated. Effective doses due to 222 Rn and gamma rays inside the mine were determined, resulting in negligible values to tourists. Considering the effective dose to the mine tourist guides, values exceeding 20 mSv of internal contribution to the effective doses can be reached, depending on the number of working hours inside the mine.

  12. Viscoelastic gravel-pack carrier fluid

    Nehmer, W.L.

    1988-01-01

    The ability of a fluid to flow adequately into the formation during gravel-pack treatments is critical to achieving a good pack. Recent studies have indicated ''fish-eyes'' and/or ''microgels'' present in many polymer gelled carrier fluids will plug pore throats, leading to impaired leakoff and causing formation damage. Intensive manipulation of the polymer gelled fluid using shear and filter devices will help remove the particles, but it adds to the cost of the treatment in terms of equipment and manpower. Excessive shear will degrade the polymer leading to poor gravel suspension, while too little shear will cause filtration problems. A gelled carried fluid using a viscoelastic surfactant system has been found to leak off very efficiently to the formation, and cause no formation damage, without the use of shear/filter devices. Viscoelastic surfactant-base gelled fluids develop viscosity because of the association of surfactant moloecules into large rod-shaped aggregates. There is no hydration of polymer involved, so fish-eyes and microgels will not be formed in the viscoelastic fluid. A surfactant-base system having a yield point allows the gravel carrying properties to be much better than fluids gelled with conventional polymer systems (hydroxyethylcellulose [HEC]). For example, a gravel carried fluid gelled with 80 lb HEC/1,000 gal has a viscosity of about 400 cp at 170 sec/sup -1/; a viscoelastic surfactant-base system having only one-half the viscosity still flows into cores about four times more efficiently than the HEC-base fluid. The rheology, leakoff, formation damage and mixing properties of a viscoelastic, surfactant-base, gravel-pack carrier fluid are discussed

  13. Decontamination process development for gravels contaminated with uranium

    Kim, Gye Nam; Park, Uk Ryang; Kim, Seung Su; Kim, Won Suk; Moon, Jei Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    It is impossible to scrub gravels in a washing tank, because gravels sinks to the bottom of the washing tank. In addition, when electrokinetic decontamination technology is applied to gravels larger than 10 cm, the removal efficiency of uranium from the gravels is reduced, because electro-osmotic flux at the surface of the gravel in electrokinetic cell reduces owing to a reduction of the particle surface area attributable to large-sized gravel. The volume ratio of gravel larger than10 cm in total volume of the soil in KAERI was about 20%. Therefore, it is necessary to study the decontamination process of gravels contaminated with radionuclides. The optimum number of washings for contaminated gravels is considered to be two. In addition, the removal efficiency of contaminated gravel was not related to its weight. For an electrokinetic-electrodialytic decontamination period of 5 days, 10 days, 15 days, and 20 days, {sup 238}U in gravel was removed by about 42%, 64%, 74%, and 80%, respectively. The more the decontamination time elapsed, the greater the reduction of the removal efficiency ratio of {sup 238}U. The decontamination process for gravels was generated on the basis of the results of washing and electrokinetic electrodialtic experiments.

  14. Variability of hyporheic exchange in an experimental gravel bed

    Perk, M. van der; Petticrew, E.L.; Owens, P.N.

    2011-01-01

    A series of tracer experiments in a large outdoor flume were conducted to examine the variability of hyporheic exchange in gravel bed sediments. An 18 m long section of a 2 m wide flume was filled with a 30 cm thick gravel layer with a porosity of 0.39. The gravel of the 17 cm top layer was

  15. Mined-out land

    Reinsalu, Enno; Toomik, Arvi; Valgma, Ingo

    2002-01-01

    Estonian mineral resources are deposited in low depth and mining fields are large, therefore vast areas are affected by mining. There are at least 800 deposits with total area of 6,000 km 2 and about the same number of underground mines, surface mines, peat fields, quarries, and sand and gravel pits. The deposits cover more than 10% of Estonian mainland. The total area of operating mine claims exceeds 150 km 2 that makes 0.3 % of Estonian area. The book is written mainly for the people who are living or acting in the area influenced by mining. The observations and research could benefit those who are interested in geography and environment, who follow formation and look of mined-out landscapes. The book contains also warnings for careless people on and under the surface of the mined-out land. Part of the book contains results of the research made in 1968-1993 by the first two authors working at the Estonian branch of A.Skochinsky Institute of Mining. Since 1990, Arvi Toomik continued this study at the Northeastern section of the Institute of Ecology of Tallinn Pedagogical University. Enno Reinsalu studied aftereffects of mining at the Mining Department of Tallinn Technical University from 1998 to 2000. Geographical Information System for Mining was studied by Ingo Valgma within his doctoral dissertation, and this book is one of the applications of his study

  16. Water and chemical budgets of gravel pit lakes : Case studies of fluvial gravel pit lakes along the Meuse River (The Netherlands) and coastal gravel pit lakes along the Adriatic Sea (Ravenna, Italy)

    Mollema, P.N.

    2016-01-01

    Gravel pit lakes form when gravel is excavated from below the water table of a phreatic or shallow confined aquifer. Typically many of these lakes are concentrated along naturally occurring sedimentary gravel deposits in areas where gravel is needed for construction. Most gravel pit lakes are

  17. Effect of gravel on hydraulic conductivity of compacted soil liners

    Shelley, T.L.; Daniel, D.E.

    1993-01-01

    How much gravel should be allowed in low-hydraulic-conductivity, compacted soil liners? To address this question, two clayey soils are uniformly mixed with varying percentages of gravel that, by itself, has a hydraulic conductivity of 170 cm/s. Soil/gravel mixtures are compacted and then permeated. Hydraulic conductivity of the compacted gravel/soil mixtures is less than 1 x 10 -7 cm/s for gravel contents as high as 50-60%. For gravel contents ≤ 60%, gravel content is not important: all test specimens have a low hydraulic conductivity. For gravel contents > 50-60%, the clayey soils does not fill voids between gravel particles, and high hydraulic conductivity results. The water content of the nongravel fraction is found to be a useful indicator of proper moisture conditions during compaction. From these experiments in which molding water content and compactive energy are carefully controlled, and gravel is uniformly mixed with the soil, it is concluded that the maximum allowable gravel content is approximately 50%

  18. Argentina; Argentine

    NONE

    2001-04-01

    This economical study summarizes the energy situation of Argentina: energy institutions and policy, energy companies (oil, electricity, gas, coal), energy supplies (resources, power production, petroleum, natural gas), prices and tariffs, consumption, economical stakes and perspectives (investments, agreements, projects). Energy data for the 1971-1999 period are summarized in graphs and tables. (J.S.)

  19. Controls on the abruptness of gravel-sand transitions

    Venditti, J. G.; Church, M. A.; Lamb, M. P.; Domarad, N.; Rennie, C. D.

    2014-12-01

    As gravel-bedded rivers fine downstream, they characteristically exhibit an abrupt transition from gravel- to sand-bed. This is the only abrupt transition in grain-size that occurs in the fluvial system and has attracted considerable attention. A number of competing theories have been proposed to account for the abruptness of the transition, including base-level control, attrition of ~10mm gravel to produce sand, and sediment sorting processes. The prevailing theory for the emergence of abrupt transitions is size selective sorting of bimodal sediment wherein gravel deposits due to downstream declining shear stress, fining the bedload until a sand-bed emerges. We explored this hypothesis by examining grain-size, shear stress, gravel mobility and sand suspension thresholds through the gravel-sand transition (GST) of the Fraser River, British Columbia. The Fraser GST is an arrested gravel wedge with patches of gravel downstream of the wedge forming a diffuse extension. There is an abrupt change in bed slope through the transition that leads to an abrupt change in shear stress. The GST, bed-slope change and backwater caused by the ocean are all coincident spatially, which enhances the sharpness of the GST. Interestingly, the bimodal reach of the river occurs downstream of the GST and exhibits no downstream gradients in shear stress, suspended sediment flux, gravel mobility or sand suspension thresholds. This calls into question the prevailing theory for the emergence of an abrupt GST by size selective sorting. We provide evidence, both empirical and theoretical, that suggests the emergence of an abrupt GST is caused by rapid deposition of sand when fine gravel deposits. We argue that the emergence of gravel-sand transitions is a consequence of gravel-bedded rivers adopting a steeper slope than sand-bedded rivers. The abruptness arises because the bed slope required to convey the gravel load fixes the distal location of a terminal gravel wedge, and once the river has

  20. Norm survey in Argentina

    Canoba, Analia Cecilia; Gnoni, Gabriela Alejandra; Truppa, W.

    2008-01-01

    The oil and gas industry, which is especially significant in Argentina, is one industry that concentrates natural radionuclides during its processes. In addition, there are a few underground mines under development, where radon levels may be high. The Nuclear Regulatory Authority of Argentina (ARN) carried out a project with the objective of evaluating NORM, mainly in these types of industries. Eight facilities were characterized, three related to the gas industry, four related to the oil industry and a survey of radon gas in a gold underground mine. First, background measurements were made and then a screening survey was carried out to detect values above background. Of the values obtained, 57% were in the background range, 19% were below 2 μSv/h, 15% were in the range 2-10 μSv/h and 9% were above 10 μSv/h. Some values were as high as 400 μSv/h. The annual effective doses were estimated to be in the range 0.02-1.6 mSv/a. Samples were taken and later analysed by gamma spectrometry, liquid scintillation and fluorimetry. It was confirmed that the main radionuclides involved in the oil and gas extraction process are 226 Ra and 228 Ra. The radium isotope concentrations measured in some samples were above the exemption values established by the International Basic Safety Standards. Elevated radon levels were detected in gas facilities and in the gold mine under development. The values obtained in gas facilities showed that radon concentrates in the ethane and propane flows. As the flows in the gas industry are confined, it does not mean an exposure during normal operation. In the case of the gold mine, the values detected were informed to the pertinent authorities as well as the facility in order to take actions to reduce concentrations below the action levels. Finally, protective measures to reduce occupational doses in the cleaning and maintenance processes were suggested, as well as for storage of NORM-contaminated items. (author)

  1. A 2D hydrodynamic-sedimentological model for gravel-bed rivers. Part I: theory and validation

    Gabriel Kaless; Mario A. Lenzi; Luca Mao

    2013-01-01

    This paper presents a novel 2D-depth average model especially developed for gravel-bed rivers, named Lican-Leufú (Lican=pebble and Leufu=river, in Mapuche’s language, the native inhabitants of Central Patagonia, Argentina). The model consists of three components: a hydrodynamic, a sedimentological, and a morphological model. The flow of water is described by the depth-averaged Reynolds equations for unsteady, free-surface, shallow water flows. It includes the standard k-e model for turbulence...

  2. Recovering byproduct heavy minerals from sand and gravel, placer gold, and industrial mineral operations

    Gomes, J.M.; Martinez, G.M.; Wong, M.M.

    1979-01-01

    The Bureau of Mines, as part of an effort to maximize minerals and metals recovery from domestic resources, has investigated the feasibility of recovering heavy minerals as byproducts from sand and gravel, placer gold, and industrial mineral operations in northern California. Sand samples from about 50 locations were treated by gravity separation to yield heavy-mineral cocentrates (black sands). Mineral compositions of the concentrates were determined by chemical analysis and mineralogical examination. Individual zircon, ilmenite, magnetite, platinum-group metals, thoria, and silica products were prepared from heavy-mineral concentrates by selective separation using low- and high-intensity magnetic, high-tension, and flotation equipment.

  3. Experimental Study of Irregular Waves on a Gravel Beach

    Hu, Nai-Ren; Wu, Yun-Ta; Hwung, Hwung-Hweng; Yang, Ray-Yeng

    2017-04-01

    In the east coast of Taiwan, the sort grain size more belongs to cobble or gravel, which is physically distinct compared to the sandy beach in the west coast of Taiwan. Although gravel beaches can dissipate more of wave energy, gravel beaches were eroded and coastal road were damaged especially during typhoons. The purpose of this study is to investigate the geomorphological response of gravel beach due to irregular waves. This experiment was carry out in a 21m long, 50 cm wide, 70 cm high wave tank at Tainan Hydraulics Laboratory, National Cheng-Kung University, Taiwan. To simulate of the geometry in the east coast of Taiwan, a physical model with 1/36 scale-down was used, in which the seawall was 10cm built upon a 1:10 slope and gravel grains with D50 being 3.87 mm was nourished in front of the seawall. In terms of typhoon-scale wave condition, irregular waves with scale-down conditions were generated for 600 s for each scenarios and, three different water levels with respect to the gravel beach are designed. Application of laser combined with image processing to produce 3D topographic map, the erosion zone and accretion zone would be found. The resulting morphological change of gravel beach will be measured using an integrated laser and image processing tool to have 3D topographic maps. It is expected to have more understanding about under what conditions the gravel coasts suffer the least damage. In particular, the relation between erosion rates of gravel beach, the angle of gravel slope and the length of the plane on the gravel slope will be achieved

  4. Can coarse surface layers in gravel-bedded rivers be mobilized by finer gravel bedload?

    Venditti, J. G.; Dietrich, W. E.; Nelson, P. A.; Wydzga, M. A.; Fadde, J.; Sklar, L.

    2005-12-01

    In response to reductions in sediment supply, gravel-bed rivers undergo a coarsening of the sediments that comprise the river's bed and, over some longer time scale, a river's grade may also be reduced as sediments are depleted from upstream reaches. Coarse, degraded river reaches are commonly observed downstream of dams across the Western United States. Following dam closure, these riverbeds become immobile under the altered flow and sediment supply regimes, leading to a reduction in the available salmon spawning and rearing habitat. Gravel augmentation to these streams is now common practice. This augmentation is typically seen as resurfacing the static coarse bed. As an alternative, we propose that the addition of appropriately finer gravels to these channels may be capable of mobilizing an otherwise immobile coarse surface layer, creating the potential to release fine material trapped beneath the surface. A series of laboratory experiments are being undertaken to test this hypothesis in a 30 m long and 0.86 m wide gravel-bedded flume channel using a constant discharge and a unimodal bed sediment with a median grain size of 8 mm and no sand present. The channel width-to-depth ratio of ~4 suppresses the development of lateral topography and allows us to focus on grain-to-grain interactions. Experiments proceed by maintaining a constant sediment feed until an equilibrium grade and transport rate are established, starving the flume of sediment for at least 24 hours, and then adding narrowly graded gravel over a period of one to two hours at a rate that is ~4x the bedload rate observed prior to terminating the sediment supply. The bed prior to sediment addition has an armor median grain size that is typically twice that of the subsurface and feed size distribution. The volume and median grain size of the resulting pulses are varied. Pulses move downstream rapidly with well-defined fronts in the form of bedload sheets and cause peaks in the sediment flux

  5. Discrete Element Modeling of the Mobilization of Coarse Gravel Beds by Finer Gravel Particles

    Hill, K. M.; Tan, D.

    2012-12-01

    Recent research has shown that the addition of fine gravel particles to a coarse bed will mobilize the coarser bed, and that the effect is sufficiently strong that a pulse of fine gravel particles can mobilize an impacted coarser bed. Recent flume experiments have demonstrated that the degree of bed mobilization by finer particles is primarily dependent on the particle size ratio of the coarse and fine particles, rather than absolute size of either particle, provided both particles are sufficiently large. However, the mechanism behind the mobilization is not understood. It has previously been proposed that the mechanism is driven by a combination of geometric effects and hydraulic effects. For example, it has been argued that smaller particles fill in gaps along the bed, resulting in a smoother bed over which the larger particles are less likely to be disentrained and a reduced near-bed flow velocity and subsequent increased drag on protruding particles. Altered near-bed turbulence has also been cited as playing an important role. We perform simulations using the discrete element method with one-way fluid-solid coupling to conduct simulations of mobilization of a gravel bed by fine gravel particles. By independently and artificially controlling average and fluctuating velocity profiles, we systematically investigate the relative role that may be played by particle-particle interactions, average near-bed velocity profiles, and near-bed turbulence statistics. The simulations indicate that the relative importance of these mechanisms changes with the degree of mobilization of the bed. For higher bed mobility similar to bed sheets, particle-particle interactions, plays a significant role in an apparent rheology in the bed sheets, not unlike that observed in a dense granular flow of particles of different sizes. For conditions closer to a critical shear stress for bedload transport, the near-bed velocity profiles and turbulence statistics become increasingly important.

  6. Abrasion-set limits on Himalayan gravel flux.

    Dingle, Elizabeth H; Attal, Mikaël; Sinclair, Hugh D

    2017-04-26

    Rivers sourced in the Himalayan mountain range carry some of the largest sediment loads on the planet, yet coarse gravel in these rivers vanishes within approximately 10-40 kilometres on entering the Ganga Plain (the part of the North Indian River Plain containing the Ganges River). Understanding the fate of gravel is important for forecasting the response of rivers to large influxes of sediment triggered by earthquakes or storms. Rapid increase in gravel flux and subsequent channel bed aggradation (that is, sediment deposition by a river) following the 1999 Chi-Chi and 2008 Wenchuan earthquakes reduced channel capacity and increased flood inundation. Here we present an analysis of fan geometry, sediment grain size and lithology in the Ganga Basin. We find that the gravel fluxes from rivers draining the central Himalayan mountains, with upstream catchment areas ranging from about 350 to 50,000 square kilometres, are comparable. Our results show that abrasion of gravel during fluvial transport can explain this observation; most of the gravel sourced more than 100 kilometres upstream is converted into sand by the time it reaches the Ganga Plain. These findings indicate that earthquake-induced sediment pulses sourced from the Greater Himalayas, such as that following the 2015 Gorkha earthquake, are unlikely to drive increased gravel aggradation at the mountain front. Instead, we suggest that the sediment influx should result in an elevated sand flux, leading to distinct patterns of aggradation and flood risk in the densely populated, low-relief Ganga Plain.

  7. The Development of Treatment Process Technology for Radioactive Gravel

    Shon, Dong Bin; Kim, Gye Nam; Park, Hye Min; Kim, Ki Hong; Kim, Wan Suk; Lee, Kun Woo; Lee, Ki Won; Moon, Jei Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2011-10-15

    The soil washing method holds great promise for the decontamination of contaminated soil as it is very efficient at removal and is time-effective for a great deal of contaminated soils. In addition, this method compensates for a weak point in that is generates a great deal of uranium-contaminated leachate with a short reaction time. Therefore, the soil washing method technology is a good method to remove the initial radioactive substance. The soil dimension compositions consist of clay with small particle sizes, and gravel of larger particle sizes than clay. Also, large gravel creates several problems. Gravel weakens the intensity of the equipment. In addition, intercept soil is discharged in the equipment. And interfere with the pedal recurrence occurs. Therefore, it is necessary to classify the soil. The gravel particle size ranges from 0.5cm to 7.5cm and the granulated gravel particle size ranges from 7.5cm to 20cm. We suppose that the radioactive concentrations are stronger in soil particles larger than the soil particle size (below a 0.5cm diameter). The purpose of this study is to develop a soil washing system for uranium gravel and to define the most suitable operational conditions for the individual elemental equipment in a soil washing system for decontaminating the radioactive gravel from contaminated soil

  8. Removal of uranium from gravel using soil washing method

    Kim, Ilgook; Kim, Kye-Nam; Kim, Seung-Soo; Choi, Jong-Won [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    The development of nuclear technology has led to increasing radioactive waste containing uranium being released and disposed in the nuclear sites. Fine grained soils with a size of less than 4 mm are normally decontaminated using soil washing and electro-kinetic technologies. However, there have been few studies on the decontamination of gravels with a size of more than 4 mm. Therefore, it is necessary to study the decontamination of gravel contaminated with radionuclides. The main objective of the present study on soil washing was to define the optimal condition for acid treatment of uranium-polluted gravel. In this study, soil washing method was applied to remove uranium from gravel. The gravel was crushed and classified as particle sizes. The gravel particles were treated with sulfuric acid in a shaking incubator at 60 .deg. C and 150 rpm for 3 h. The optimal particle size of gravel for soil washing in removal of uranium was between 0.45 and 2.0 mm.

  9. Experiment on Physical Desalinisation of Uranium-contaminated Gravel Surface

    Park, Uk-Ryang; Kim, Gye-Nam; Kim, Seung-Soo; Han, Gyu-Seong; Moon, Jai-Kwon

    2014-01-01

    As a result, the method to wash uranium-contaminated gravels could not get satisfactory desalinization rate. During the long oxidization process it was judged that uranium penetrated inside the gravels, so we tried to increase the desalinization rate by fragmentizing them into pieces and then washing them. The desalinization rate after fragmentizing the gravels into pieces and washing them brought a satisfactory result.. However, we could obtain desired concentration for gravels with high uranium concentration by fragmentizing them and breaking them further into even smaller pieces. Likewise, desalinization using soil washing process is complicated and has to go through multiple washing steps, resulting in too much of waste fluid generated accordingly. The increase of waste fluid generated leads to the increase in by-products of the final disposal process later on, bringing a not good economic result. Furthermore, taking into account that the desalinization rate is 65% during soil washing process, it is expected that gravel washing will show a similar desalinization result; it is considered uneasy to have a perfect desalinization only by soil washing. The grinding method is actually used in the primary desalinization process in order to desalinize radioactivity-contaminated concrete. This method does desalinization by grinding the radioactivity-contaminated area of the concrete surface with desalinization equipment, which enables a near-to-perfect desalinization for relatively thinly contaminated surface. Likewise, this research verified the degree of desalinization by applying the grinding method and comparing it to the fragmentizing-washing method, and attempted to find a method to desalinize uranium-contaminated gravels more effectively. In order to desalinize uranium-contaminated gravels more effectively and compare to the existing washing-desalinization method, we conducted a desalinization experiment with grinding method that grinds gravel surface. As a

  10. Quantification of Gravel Rural Road Sediment Production

    Silliman, B. A.; Myers Toman, E.

    2014-12-01

    Unbound rural roads are thought to be one of the largest anthropogenic sources of sediment reaching stream channels in small watersheds. This sediment deposition can reduce water quality in the streams negatively impacting aquatic habitat as well as impacting municipal drinking water sources. These roads are thought to see an increase in construction and use in southeast Ohio due to the expansion of shale gas development in the region. This study set out to quantify the amount of sediment these rural roads are able to produce. A controlled rain event of 12.7 millimeters of rain over a half hour period was used to drive sediment production over a 0.03 kilometer section of gravel rural road. These 8 segments varied in many characteristics and produced from 2.0 to 8.4 kilograms of sediment per 0.03 kilometers of road with the average production over the 8 segments being 5.5 kilograms of sediment. Sediment production was not strongly correlated with road segment slope but traffic was found to increase sediment production from 1.1 to 3.9 times as much sediment after traffic use. These results will help inform watershed scale sediment budgeting, and inform best management practices for road maintenance and construction. This study also adds to the understanding of the impacts of rural road use and construction associated with the changing land use from agricultural to natural gas extraction.

  11. Gravel addition as a habitat restoration technique for tailwaters

    Ryan McManamay; D. Orth; Charles Dolloff; Mark Cantrell

    2010-01-01

    We assessed the efficacy of passive gravel addition at forming catostomid spawning habitat under various flow regimes in the Cheoah River, a high-gradient tailwater river in North Carolina. The purpose was to provide a case study that included recommendations for future applications. A total of 76.3 m3 (162 tons) of washed gravel (10-50 mm) was passively dumped down...

  12. Noise Exposure and Hearing Loss Among Sand and Gravel Miners

    Landen, Deborah; Wilkins, Steve; Stephenson, Mark; McWilliams, Linda

    2004-01-01

    The objectives of this study were to describe workplace noise exposures, risk factors for hearing loss, and hearing levels among sand and gravel miners, and to determine whether full shift noise exposures resulted in changes in hearing thresholds from baseline values. Sand and gravel miners (n = 317) were interviewed regarding medical history, leisure-time and occupational noise exposure, other occupational exposures, and use of hearing protection. Audiometric tests were performed both before...

  13. Gravel Mobility in a High Sand Content Riverbed

    Haschenburger, J. K.

    2017-12-01

    In sand-gravel channels, sand may modify gravel transport by changing conditions of entrainment and promoting longer displacements or gravel may inhibit sand transport if concentrated into distinct deposits, which restrict sand supply with consequences for migrating bedform size or form. This study reports on gravel mobility in the lower San Antonio River, Texas, where gravel content in the bed material ranges from about 1% to more than 20%. Sediment transport observations were collected at three U.S. Geological Survey gauging stations by deploying a Helley-Smith sampler with a 0.2 mm mesh bag from which transport rates and mobile grain sizes were determined. The flow rates sampled translate into an annual exceedance expectation from 0.2% to 98%. Gravel transport rates are generally two orders of magnitude smaller than the rates of sand transport. However, the finest gravels are transported at rates on the same order of magnitude as the coarsest sands. At all sites, the 2 and 2.8 mm fractions are transported at the lowest flow rate sampled, suggesting mobility for at least 38% to as much as 98% of the year. Fractions as large as 8 mm are mobilized at flow rates that are expected between 25% and 53% of the year. The largest fractions captured in the sampling (16 to 32 mm) require flows closer to bankfull conditions that occur no more than 0.8% of the year. Results document that some gravel sizes can be frequently transported in low gradient riverbeds with high sand content.

  14. Reservoir architecture patterns of sandy gravel braided distributary channel

    Senlin Yin

    2016-06-01

    Full Text Available The purpose of this study was to discuss shape, scale and superimposed types of sandy gravel bodies in sandy-gravel braided distributary channel. Lithofacies analysis, hierarchy bounding surface analysis and subsurface dense well pattern combining with outcrops method were used to examine reservoir architecture patterns of sandy gravel braided distributary channel based on cores, well logging, and outcrops data, and the reservoir architecture patterns of sandy gravel braided distributary channels in different grades have been established. The study shows: (1 The main reservoir architecture elements for sandy gravel braided channel delta are distributary channel and overbank sand, while reservoir flow barrier elements are interchannel and lacustrine mudstone. (2 The compound sand bodies in the sandy gravel braided delta distributary channel take on three shapes: sheet-like distributary channel sand body, interweave strip distributary channel sand body, single strip distributary channel sand body. (3 Identification marks of single distributary channel include: elevation of sand body top, lateral overlaying, “thick-thin-thick” feature of sand bodies, interchannel mudstone and overbank sand between distributary channels and the differences in well log curve shape of sand bodies. (4 Nine lithofacies types were distinguished in distributary channel unit interior, different channel units have different lithofacies association sequence.

  15. Washing technology development for gravel contaminated with uranium

    Park, Uk Ryang; Kim, Gye Nam; Kim, Seung Soo; Kim, Wan Suk; Moon, Jai Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    The soil washing method has a short decontamination time and is economical. In addition, methods including phytoremediation, solidification/stabilization and bioremediation exist. Phytoremediation and bioremediation are economical, but have low remedial efficiency. In addition, bioremediation causes washing wastewater because it requires a washing process for the separation of microorganisms from the soils. In addition, solidification/stabilization is a commonly used methods, but eventually increases the volume of wastes. As mentioned above, many researches involved in the decontamination of radioactively contaminated soils have been actively processed. On the other hand, researches for decontaminating radioactively contaminated gravels are not being currently processed. In this study, we performed basic experiments using decontamination methods to decontaminate radioactively contaminated gravel. First, we measured the concentration of uranium in gravel included in uranium-contaminated soils and performed a washing experiment to monitor the tendency of uranium removal. In addition, when managing gravel with a low uranium-decontamination rate, we tried to satisfy the radioactivity concentration criteria for self-disposal in the wastes (0.4Bq/g or less) by performing a washing experiment after only a physical crushing process. We performed washing experiments to satisfy the radioactivity concentration criteria for self-disposal (0.4 Bq/g or less) in gravel included in radioactively contaminated soil. We performed washing experiments for gravel whose initial average concentration of uranium was 1.3Bq/g. In addition, the average concentration of uranium was 0.8Bq/g. Too increase the decontamination rate, we crushed the gravel with a jaw crusher and performed the washing experiments. The results were similar to the results without crushing. In addition, it was determined that the smaller the size of the gravel particles, the more efficient the uranium decontamination

  16. Performance of high-rate gravel-packed oil wells

    Unneland, Trond

    2001-05-01

    Improved methods for the prediction, evaluation, and monitoring of performance in high-rate cased-hole gravel-packed oil wells are presented in this thesis. The ability to predict well performance prior to the gravel-pack operations, evaluate the results after the operation, and monitor well performance over time has been improved. This lifetime approach to performance analysis of gravel-packed oil wells contributes to increase oil production and field profitability. First, analytical models available for prediction of performance in gravel-packed oil wells are reviewed, with particular emphasis on high-velocity flow effects. From the analysis of field data from three North Sea oil fields, improved and calibrated cased-hole gravel-pack performance prediction models are presented. The recommended model is based on serial flow through formation sand and gravel in the perforation tunnels. In addition, new correlations for high-velocity flow in high-rate gravel-packed oil wells are introduced. Combined, this improves the performance prediction for gravel-packed oil wells, and specific areas can be targeted for optimized well design. Next, limitations in the current methods and alternative methods for evaluation and comparison of well performance are presented. The most widely used parameter, the skin factor, remains a convenient and important parameter. However, using the skin concept in direct comparisons between wells with different reservoir properties may result in misleading or even invalid conclusions. A discussion of the parameters affecting the skin value, with a clarification of limitations, is included. A methodology for evaluation and comparison of gravel-packed well performance is presented, and this includes the use of results from production logs and the use of effective perforation tunnel permeability as a parameter. This contributes to optimized operational procedures from well to well and from field to field. Finally, the data sources available for

  17. Recolonization of gravel habitats on Georges Bank (northwest Atlantic)

    Collie, Jeremy S.; Hermsen, Jerome M.; Valentine, Page C.

    2009-09-01

    Gravel habitats on continental shelves around the world support productive fisheries but are also vulnerable to disturbance from bottom fishing. We conducted a 2-year in situ experiment to measure the rate of colonization of a gravel habitat on northern Georges Bank in an area closed to fishing (Closed Area II) since December 1994. Three large (0.25 m 2) sediment trays containing defaunated pebble gravel were deployed at a study site (47 m water depth) in July 1997 and recovered in June 1999. The undersides of the tray lids positioned 56 cm above the trays served as settlement panels over the same time period. We observed rapid colonization of the gravel substrate (56 species) and the settlement panels (35 species), indicating that colonization of gravel in this region is not limited by the supply of colonists. The species composition of the taxa found in the trays was broadly similar to that we collected over a 10-year period (1994-2004) in dredge samples from gravel sediments at the same site. The increase in abundance of animals in the gravel colonization trays was rapid and reached a level in 2 years that took 4.5 years to achieve in the surrounding gravel sediments once fishing had stopped, based on data from dredge sampling at this site. The increase in biomass of animals found in the sediment trays paralleled the trend of biomass increase observed in dredge samples over the same period (1997-1999) but was lower in value. These data suggest that after rapid initial increase in abundance of organisms, succession proceeded by increasing individual body size. A comparison of settlement panel and tray faunas revealed that the mean biomass of structure-forming epifauna (sponges, bryozoans, anemones, hydroids, colonial tube worms) on the panels was 8 times that found on the trays. Structure-forming taxa constituted 29% of the mean biomass of the panel fauna but only 5.5% of the tray fauna. By contrast, the mean biomass of scavengers (crabs, echinoderms, nudibranchs

  18. Recolonization of gravel habitats on Georges Bank (northwest Atlantic)

    Collie, Jeremy S.; Hermsen, Jerome M.; Valentine, Page C.

    2009-01-01

    Gravel habitats on continental shelves around the world support productive fisheries but are also vulnerable to disturbance from bottom fishing. We conducted a 2-year in situ experiment to measure the rate of colonization of a gravel habitat on northern Georges Bank in an area closed to fishing (Closed Area II) since December 1994. Three large (0.25 m2) sediment trays containing defaunated pebble gravel were deployed at a study site (47 m water depth) in July 1997 and recovered in June 1999. The undersides of the tray lids positioned 56 cm above the trays served as settlement panels over the same time period. We observed rapid colonization of the gravel substrate (56 species) and the settlement panels (35 species), indicating that colonization of gravel in this region is not limited by the supply of colonists. The species composition of the taxa found in the trays was broadly similar to that we collected over a 10-year period (1994-2004) in dredge samples from gravel sediments at the same site. The increase in abundance of animals in the gravel colonization trays was rapid and reached a level in 2 years that took 4.5 years to achieve in the surrounding gravel sediments once fishing had stopped, based on data from dredge sampling at this site. The increase in biomass of animals found in the sediment trays paralleled the trend of biomass increase observed in dredge samples over the same period (1997-1999) but was lower in value. These data suggest that after rapid initial increase in abundance of organisms, succession proceeded by increasing individual body size. A comparison of settlement panel and tray faunas revealed that the mean biomass of structure-forming epifauna (sponges, bryozoans, anemones, hydroids, colonial tube worms) on the panels was 8 times that found on the trays. Structure-forming taxa constituted 29% of the mean biomass of the panel fauna but only 5.5% of the tray fauna. By contrast, the mean biomass of scavengers (crabs, echinoderms, nudibranchs

  19. Treatment of Gravel Contaminated with Naturally Occurring Radioactive Element

    Sohsah, M. A.; Kamal, S. M.; Mamoon, A.

    2004-01-01

    Environmental protection primarily means controlling the releases of radioactive and non-radioactive wastes to the environment and involves treatment, storage, cleanup and disposal of these wastes. The present study concerns the cleanup of gravel that has been contaminated with 2 26 R a. Aqueous solutions of different compositions including water and various concentrations of calcium chloride and barium chloride were used to leach the contaminated gravel. The leaching experiments were carried out in glass column. In some leaching experiments, samples of sandy soil were placed below the gravel to test the sorption of the leached 2 26 R a by the soil. The relative efficiencies of the leachant and the extent of sorption of the leached radionuclide were determined both by the liquid scintillation counting and by the thermoluminescent chips. The TLD chips record the dose before and after decontamination of the gravel and before and after contamination of the soil samples when used. The results obtained indicated that acidified barium chloride was relatively the most effective leachant of 2 26 R a contamination. It reduced the dose from the contaminated gravel to almost half. The soil sample used adsorbs the leached radionuclides efficiently, increasing the soil naturally low dose to about six folds

  20. Leaching of RA-226 contaminated gravel using different aqueous treatments

    Mamoon, A; Abulfaraj, W H; Sohsah, M A [King Abdulaziz University, Jeddah, Saudi Arbabia (Saudi Arabia)

    1997-12-31

    Investigation of the efficiencies of different aqueous leaching treatments was carried out on gravel artificially contaminated with Ra-226. The extent of leaching efficiency was determined in terms of Ra-226 and its daughter Rn-222. Liquid scintillation counting using high efficiency mineral oil based liquid scintillator was the technique adopted for measuring Ra-226 and Rn-222 leached off the contaminated gravel. Water, dilute solutions of barium chloride and HCl were used as leachants. Different masses of gravel were leached with 200 mL of leachant for various contact time periods. The leached Rn-222 activity measured was plotted vs the decay factor e; from which Rn-222 and Ra-226 originally present in the sample were determined. Several leaching parameters were tested; namely type of leachant, leachant volume/gravel mass ratio, leachant contact time, effect of varying Ba Cl{sub 2} concentration, and successive leaching. Optimization of the leaching parameters for desorption of Ra-226 off the contaminated gravel under laboratory conditions may help determine the ideal conditions for remediating soil contaminated with radium or chemically similar radionuclides. 7 figs.

  1. Chapter J: Issues and challenges in the application of geostatistics and spatial-data analysis to the characterization of sand-and-gravel resources

    Hack, Daniel R.

    2005-01-01

    Sand-and-gravel (aggregate) resources are a critical component of the Nation's infrastructure, yet aggregate-mining technologies lag far behind those of metalliferous mining and other sectors. Deposit-evaluation and site-characterization methodologies are antiquated, and few serious studies of the potential applications of spatial-data analysis and geostatistics have been published. However, because of commodity usage and the necessary proximity of a mine to end use, aggregate-resource exploration and evaluation differ fundamentally from comparable activities for metalliferous ores. Acceptable practices, therefore, can reflect this cruder scale. The increasing use of computer technologies is colliding with the need for sand-and-gravel mines to modernize and improve their overall efficiency of exploration, mine planning, scheduling, automation, and other operations. The emergence of megaquarries in the 21st century will also be a contributing factor. Preliminary research into the practical applications of exploratory-data analysis (EDA) have been promising. For example, EDA was used to develop a linear-regression equation to forecast freeze-thaw durability from absorption values for Lower Paleozoic carbonate rocks mined for crushed aggregate from quarries in Oklahoma. Applications of EDA within a spatial context, a method of spatial-data analysis, have also been promising, as with the investigation of undeveloped sand-and-gravel resources in the sedimentary deposits of Pleistocene Lake Bonneville, Utah. Formal geostatistical investigations of sand-and-gravel deposits are quite rare, and the primary focus of those studies that have been completed is on the spatial characterization of deposit thickness and its subsequent effect on ore reserves. A thorough investigation of a gravel deposit in an active aggregate-mining area in central Essex, U.K., emphasized the problems inherent in the geostatistical characterization of particle-size-analysis data. Beyond such factors

  2. Liquid filtration properties in gravel foundation of railroad tracks

    Strelkov, A; Teplykh, S; Bukhman, N

    2016-01-01

    Railway bed gravel foundation has a constant permanent impact on urban ecology and ground surface. It is only natural that larger objects, such as railway stations, make broader impact. Surface run-off waters polluted by harmful substances existing in railroad track body (ballast section) flow along railroad tracks and within macadam, go down into subterranean ground flow and then enter neighbouring rivers and water basins. This paper presents analytic calculations and characteristics of surface run-off liquid filtration which flows through gravel multiple layers (railroad track ballast section). The authors analyse liquids with various density and viscosity flowing in multi-layer porous medium. The paper also describes liquid stationary and non-stationary weepage into gravel foundation of railroad tracks. (paper)

  3. Medical revolution in Argentina.

    Ballarin, V L; Isoardi, R A

    2010-01-01

    The paper discusses the major Argentineans contributors, medical physicists and scientists, in medical imaging and the development of medical imaging in Argentina. The following are presented: history of medical imaging in Argentina: the pioneers; medical imaging and medical revolution; nuclear medicine imaging; ultrasound imaging; and mathematics, physics, and electronics in medical image research: a multidisciplinary endeavor.

  4. Argentina's nuclear red herring

    Perera, J.

    1983-01-01

    The article deals with Argentina's nuclear power programme over the last 30 years, including the country's efforts to be nuclear independent of the United States, as well as its aspirations to be a nuclear supplier to latin America. The latter policy on economic, rather than military grounds for nuclear weapons, has led to Argentina's decision to build a uranian enrichment plant. (U.K.)

  5. A 2D hydrodynamic-sedimentological model for gravel-bed rivers. Part I: theory and validation

    Gabriel Kaless

    2013-09-01

    Full Text Available This paper presents a novel 2D-depth average model especially developed for gravel-bed rivers, named Lican-Leufú (Lican=pebble and Leufu=river, in Mapuche’s language, the native inhabitants of Central Patagonia, Argentina. The model consists of three components: a hydrodynamic, a sedimentological, and a morphological model. The flow of water is described by the depth-averaged Reynolds equations for unsteady, free-surface, shallow water flows. It includes the standard k-e model for turbulence closure. Sediment transport can be divided in different size classes (sand-gravel mixture and the equilibrium approach is used for Exner’s equation. The amour layer is also included in the structure of the model and the surface grain size distribution is also allowed to evolve. The model simulates bank slides that enable channel widening. Models predictions were tested against a flume experiment where a static armour layer was developed under conditions of sediment starvations and general good agreements were found: the model predicted adequately the sediment transport, grain size of transported material, final armour grain size distribution and bed elevation.

  6. Stabilizing cinder gravels for heavily trafficked base course ...

    Investigation into the improvement of natural cinder gravels with the use of stabilization techniques was made using samples collected from quarry sites near Alemgena and Lake Chamo. Mechanical and cement stabilizations were investigated in two subsequent phases. In the first phase, optimum amount of fine soils that ...

  7. stabilization of cinder gravel with cment for base course

    Girma Berhanu

    techniques was made using samples collected from quarry sites near ... design standards for heavily trafficked base course without adding ... Cinder gravel, Mechanized stabilization, Optimum cement content ... respectively. In the presentation through out the .... here to indicate the general response of cement stabilization in ...

  8. Radon diffusion studies in air, gravel, sand, soil and water

    Singh, B.; Singh, S.; Virk, H.S.

    1993-01-01

    Radon isotopes are practically inert and have properties of gases under conditions of geological interest. During their brief lives their atoms are capable of moving from sites of their generation. Radon diffusion studies were carried out in air, gravel, sand, soil and water using silicon diffused junction electronic detector, Alphameter-400. Diffusion constant and diffusion length is calculated for all these materials. (author)

  9. Effects of gravel mulch on emergence of galleta grass seedlings

    Winkel, V.K.; Medrano, J.C.; Stanley, C.; Walo, M.D.

    1993-03-01

    The Department of Energy Nevada Operations Office, Technology Development and Program Management Division, has identified the need to clean up several sites on the Nevada Test Site and Tonopah Test Range contaminated with surface plutonium. An important objective of the project identified as the Plutonium In Soils Integrated Demonstration is to develop technologies to stabilize and restore the disturbed sites after decontamination. Revegetation of these contaminated sites will be difficult due to their location in the arid Mojave and Great Basin Deserts. The major factors which will affect successful plant establishment and growth at these sites are limited and sporadic precipitation, limited soil water, extreme air and soil temperatures, limited topsoil, and herbivory . Research has shown that providing microsites for seed via mulching can aid in plant emergence and establishment. Since many of the soils at the sites slated for plutonium decontamination have a large percentage of gravel in the upper 10 cm of soil, the use of gravel as mulch could provide microsites for seed and stabilize soils during subsequent revegetation of the sites. In July 1992, EG ampersand G/EM Environmental Sciences Department initiated a greenhouse study to examine the possible benefits of gravel mulch. The specific objectives of this greenhouse study were to: (1) determine the effects seedling emergence and soil water, and (2) determine effects of irrigation rates on seedling emergence for gravel mulches and other conventional seedbed preparation techniques. A secondary objective was to determine the depth of gravel mulch that was optimal for seedling emergence. Results from this greenhouse study will assist in formulating specific reclamation plans for sites chosen for cleanup

  10. Fisher Sand & Gravel New Mexico, Inc. General Air Quality Permit: Related Documents

    Documents related to the Fisher Sand & Gravel – New Mexico, Inc., Grey Mesa Gravel Pit General Air Quality Permit for New or Modified Minor Source Stone Quarrying, Crushing, and Screening Facilities in Indian Country.

  11. Macroinvertebrate Community responses to gravel addition in a Southeastern regulated river

    Ryan A. McManamay; Donald J. Orth; A. Charles. Dolloff

    2013-01-01

    Sediment transport, one of the key processes of river systems, is altered or stopped by dams, leaving lower river reaches barren of sand and gravel, both of which are essential habitat for fish and macroinvertebrates. One way to compensate for losses in sediment is to supplement gravel to river reaches below impoundments. Because gravel addition has become a widespread...

  12. LDC nuclear power: Argentina

    Tweedale, D.L.

    1982-01-01

    Argentina's 31-year-old nuclear research and power program makes it a Third World leader and the preeminent Latin American country. Easily accessible uranium fuels the heavy water reactor, Atucha I, which provides 10% of the country's electric power. Atucha II and III are under construction. Several domestic and international factors combined to make Argentina's program succeed, but achieving fuel-cycle independence and the capacity to divert fissionable material to military uses is a cause for some concern. 60 references

  13. Evidence for aeolian origins of heuweltjies from buried gravel layers

    Michael D. Cramer

    2016-02-01

    Full Text Available Although heuweltjies (19–32 m diameter dominate the surface of much of the southwestern Cape of South Africa, their origins, distribution and age remain controversial. Current hypotheses are that the heuweltjies are (1 constructed by the excavation and mounding habits of burrowing animals; (2 the result of erosion by water of areas between patches protected from fluvial action by denser vegetation or (3 the product of localised aeolian sediment accumulation beneath denser vegetation associated with termitaria. At a site where quartz-containing gravels occur on the soil surface in areas between heuweltjies, these gravels were found to extend as a relatively intact layer of uniform concentration from the inter-mound area into the mound at the same plane as the surrounding soil surface. This buried layer suggests that heuweltjies were either built-up by deposition on a previous soil surface layer or eroded from sediment accumulated above the buried gravel layer. Mounds contain a relatively large proportion of silt consistent with sediment deposition. Mound sediment elemental composition was strongly correlated with that of local shale, indicating a local source of sediment. Pedogenesis was considerably more advanced off- than on-mound. There was no evidence of extensive regional aeolian sediment mantling over the vast area in which the heuweltjies occur. These findings and observations support the aeolian deposition hypothesis of heuweltjie origins combined with a degree of erosion, rather than a termite bioturbation hypothesis or a predominantly erosion-based hypothesis.

  14. Measurement of earthquake-induced shear strain in sandy gravel

    Ohkawa, I.; Futaki, M.; Yamanouchi, H.

    1989-01-01

    The nuclear power reactor buildings have been constructed on the hard rock ground formed in or before the Tertiary in Japan. This is mainly because the nuclear reactor building is much heavier than the common buildings and requires a large bearing capacity of the underlying soil deposit, and additionally the excessive deformation in soil deposit might cause damage in reactor building and subsequently cause the malfunction of the internal important facilities. Another reason is that the Quaternary soil deposit is not fully known with respect to its dynamic property. The gravel, and the sandy gravel, the representative soils of the Quaternary, have been believed to be suitable soil deposits to support the foundation of a common building, although the soils have rarely been investigated so closely on their physical properties quantitatively. In this paper, the dynamic deformability, i.e., the shear stress-strain relationship of the Quaternary diluvial soil deposit is examined through the earthquake ground motion measurement using accelerometers, pore-pressure meters, the specific devices developed in this research work. The objective soil deposit in this research is the sandy gravel of the diluvial and the alluvial

  15. Evolution of completion tools gravel pack systems for deep water

    Pineda, Francisco [BJ Services Company, Houston, TX (United States); Vilela, Alvaro; Montanha, Roberto; Hightower, Chad; Acosta, Marco; Farias, Rodrigo [BJ Services do Brasil Ltda., Rio de Janeiro, RJ (Brazil)

    2004-07-01

    Conventional gravel pack or frac pack completions typically require the use of wash pipe to act as a conduit for fluid returns as well as to carry a shifting mechanism to open or close a return port. Using properly sized wash pipe can enhance the placement of the gravel across the entire annular space and the formation. It can also be used in conjunction with a shifting mechanism and a sliding sleeve to force the fluid returns to pass through the bottom of the screen. It can allow a wash-down capability while running the assembly into an open hole. In specialty systems, it can even act as a pumping conduit for post-gravel pack stimulation. However, the use of wash pipe, especially in long horizontal wells, means the loss of valuable rig time due to make up and break out of the wash pipe, or recovery if the wash pipe is stuck. Economic considerations, along with completion efficiencies, are especially important on deep water completions. Not using wash pipe reduces rig time, generating significant cost savings, and also eliminates the risk of a fishing operation. This paper reviews conventional wash pipe applications and describes new systems that accomplish the same goal with a minimum amount of wash pipe or no wash pipe at all. (author)

  16. Comparison of different forms of gravel as aggregate in concrete

    Sikiru ORITOLA

    2014-11-01

    Full Text Available Gradation plays an important role in the workability, segregation, and pump ability of concrete. Uniformly distributed aggregates require less paste which will also decrease bleeding, creep and shrinkage while producing better workability, more durable concrete and higher packing. This attempt looks at the effect of particle size distribution pattern for five types of gravel aggregate forms, angular, elongated, smooth rounded, irregular and flaky as related to the strength of concrete produced. Different forms of naturally existing gravel aggregate were collected from a particular location and tests were carried out on them to determine their gradation. Based on the gradation the aggregates were used to prepare different samples of grade 20 concrete with water-cement ratio of 0.5. The particle size distribution resulted in coefficients of uniformity ranging from 1.24 to 1.44. The granite aggregate, which serves as a reference, had a coefficient of uniformity of 1.47. Tests were conducted on fresh and hardened concrete cube samples. The concrete sample CT5 recorded a slump of 32mm and highest compressive strength value of 21.7 N/mm2, among the concrete produced from different forms of gravel.

  17. Ecological Effects of Re-introduction of Salmonid Spawning Gravel in Lowland Danish Streams

    Pedersen, Morten Lauge; Kristensen, Esben Astrup; Kronvang, Brian

    2009-01-01

    recently been conducted in many streams and rivers. However, systematic monitoring of these spawning gravel restoration projects is limited. The overall aim of this paper was to evaluate gravel reintroduction as a long-term salmonid rehabilitation method in 32 lowland streams. Displacement of gravel......, including both restored reaches and upstream control reaches. Downstream displacement of gravel was most common at sites where gravel was reintroduced without further improvement, although these sites exhibited the highest density of YOY brown trout (Salmo trutta), evidencing that the remaining gravel...... is still functional. The intensive study of three streams showed that spawning was enhanced by the introduction of spawning gravel at the restored sites compared to control sites and that habitat quality generally were improved. Our results also suggest complex interactions exist between spawning activity...

  18. Can we enhance amphibians? habitat restoration in the post-mining areas?

    Klimaszewski, Krzysztof; Pacholik, Ewa; Snopek, Adam

    2015-01-01

    The study was aimed to evaluate the selected improvements of nature restoration in a depleted gravel pit. The study site consisted of four water reservoirs of different shapes and sizes, flooded after the gravel extraction ended. Ecological succession monitoring, conducted by the Warsaw University of Life Sciences students associated in the Student Scientific Association of Animal Sciences Faculty since the completion of mining, have focused on amphibians. A twofold approach upheld amphibian ...

  19. Gravel sediment routing from widespread, low-intensity landscape disturbance, Current River basin, Missouri

    Jacobson, Robert B.; Gran, K.B.

    1999-01-01

    During the last 160 years, land-use changes in the Ozarks have had the potential to cause widespread, low-intensity delivery of excess amounts of gravel-sized sediment to stream channels. Previous studies have indicated that this excess gravel bedload is moving in wave-like forms through Ozarks drainage basins. The longitudinal, areal distribution of gravel bars along 160 km of the Current River, Missouri, was evaluated to determine the relative effects of valley-scale controls, tributary basin characteristics, and lagged sediment transport in creating areas of gravel accumulations. The longitudinal distribution of gravel-bar area shows a broad scale wave-like form with increases in gravel-bar area weakly associated with tributary junctions. Secondary peaks of gravel area with 1·8–4·1 km spacing (disturbance reaches) are superimposed on the broad form. Variations in valley width explain some, but not all, of the short-spacing variation in gravel-bar area. Among variables describing tributary drainage basin morphometry, present-day land use and geologic characteristics, only drainage area and road density relate even weakly to gravel-bar areal inventories. A simple, channel network-based sediment routing model shows that many of the features of the observed longitudinal gravel distribution can be replicated by uniform transport of sediment from widespread disturbances through a channel network. These results indicate that lagged sediment transport may have a dominant effect on the synoptic spatial distribution of gravel in Ozarks streams; present-day land uses are only weakly associated with present-day gravel inventories; and valley-scale characteristics have secondary controls on gravel accumulations in disturbance reaches.

  20. Helosis (Balanophoraceae en Argentina Helosis (Balanophoraceae in Argentina

    José Luis Fontana

    2006-07-01

    Full Text Available Se cita por primera vez para Argentina Helosis cayennensis (Swartz Sprengel var. cayennensis en base a colecciones hechas por los autores en la Isla argentina de Apipé Grande, Ituzaingó, provincia de Corrientes. Se describe e ilustra la especie, el desarrollo de la planta y su estado de conservación. Esta cita de Helosis corresponde a un género nuevo para la flora argentina.Helosis cayennensis var. cayennensis is reported for the first time for Argentina. The species is described and ilustrated. Developement and ecology are also given. Helosis is also a new generic record for Argentina.

  1. Trust Mines

    The United States and the Navajo Nation entered into settlement agreements that provide funds to conduct investigations and any needed cleanup at 16 of the 46 priority mines, including six mines in the Northern Abandoned Uranium Mine Region.

  2. Particulate removal processes and hydraulics of porous gravel media filters

    Minto, J. M.; Phoenix, V. R.; Dorea, C. C.; Haynes, H.; Sloan, W. T.

    2013-12-01

    Sustainable urban Drainage Systems (SuDS) are rapidly gaining acceptance as a low-cost tool for treating urban runoff pollutants close to source. Road runoff water in particular requires treatment due to the presence of high levels of suspended particles and heavy metals adsorbed to these particles. The aim of this research is to elucidate the particle removal processes that occur within gravel filters that have so far been considered as 'black-box' systems. Based on these findings, a better understanding will be attained on what influences gravel filter removal efficiency and how this changes throughout their design life; leading to a more rational design of this useful technology. This has been achieved by tying together three disparate research elements: tracer residence time distribution curves of filters during clogging; 3D magnetic resonance imaging (MRI) of clogging filters and computational fluid dynamics (CFD) modelling of complex filter pore networks. This research relates column average changes in particle removal efficiency and tracer residence time distributions (RTDs) due to clogging with non-invasive measurement of the spatial variability in particle deposition. The CFD modelling provides a link between observed deposition patterns, flow velocities and wall shear stresses as well as the explanations for the change in RTD with clogging and the effect on particle transport. Results show that, as a filter clogs, particles take a longer, more tortuous path through the filter. This is offset by a reduction in filter volume resulting in higher flow velocities and more rapid particle transport. Higher velocities result in higher shear stresses and the development of preferential pathways in which the velocity exceeds the deposition threshold and the overall efficiency of the filter decreases. Initial pore geometry is linked to the pattern of deposition and subsequent formation of preferential pathways. These results shed light on the 'black-box' internal

  3. Experimental investigation on heat transport in gravel-sand materials

    Maureschat, Gerald; Heller, Alfred

    1997-01-01

    in sand-gravel material, the storage media is to be water satured. In this case, handling of such material on site is rather complex. The conduction is highly dependent on the thermal properties of the storage media and so is the overall thermal performance of a storage applying such media. For sandy...... out in a small size experiment. The experiment consists of a highly insulated box filled with two kinds of sand material crossed by a plastic heat pipe. Heat transfer is measured under dry and water satured conditions in a cross-section.The conclusions are clear. To obtain necessary heat conduction...

  4. Geologie study off gravels of the Agua Fria River, Phoenix, AZ

    Langer, W.H.; Dewitt, E.; Adams, D.T.; O'Briens, T.

    2010-01-01

    The annual consumption of sand and gravel aggregate in 2006 in the Phoenix, AZ metropolitan area was about 76 Mt (84 million st) (USGS, 2009), or about 18 t (20 st) per capita. Quaternary alluvial deposits in the modern stream channel of the Agua Fria River west of Phoenix are mined and processed to provide some of this aggregate to the greater Phoenix area. The Agua Fria drainage basin (Fig. 1) is characterized by rugged mountains with high elevations and steep stream gradients in the north, and by broad alluvial filled basins separated by elongated faultblock mountain ranges in the south. The Agua Fria River, the basin’s main drainage, flows south from Prescott, AZ and west of Phoenix to the Gila River. The Waddel Dam impounds Lake Pleasant and greatly limits the flow of the Agua Fria River south of the lake. The southern portion of the watershed, south of Lake Pleasant, opens out into a broad valley where the river flows through urban and agricultural lands to its confluence with the Gila River, a tributary of the Colorado River.

  5. A study on the decontamination of the gravels contaminated by uranium

    Park, Ukryang; Kim, Gyenam; Kim, Seungsoo; Moon, Jaikwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    The amount of gravels contaminated by uranium is usually about 10% of the contaminated soil. Since such contaminated gravels show different kinds and volumes, it would cost a considerable amount of money if they are to be disposed of without going through any special process. Also, there has not been any particular way or technology for processing the gravels contaminated by uranium. Therefore, various fundamental experiments and researches have been carried out for the decontamination of the gravels contaminated by uranium. Through such experiments and researches, it has been possible to obtain some significant results. The acid cleaning process, which is based on the application of the soil cleaning method, can be regarded as one of the major ways used for decontamination. When the gravels contaminated by uranium are cleaned as they are, most of them tend to show an extremely-low level of decontamination. Therefore, it could be said that the inside of each gravel is also contaminated by uranium. As a result, the gravels contaminated by uranium need to be crushed before being cleaned, which would result in a higher level of efficiency for decontamination compared to the previous way. Therefore, it is more effective to crush the subject gravels before cleaning them in terms of decontamination. However, such test results can only be applied to the gravels contaminated by an average level of uranium concentration. Regarding the gravels showing a higher level of uranium concentration than the average, it is still necessary to carry out more researches. Therefore, this study focused on the level of efficiency for decontamination after the contaminated gravels were crushed before being cleaned, in order to find a way to effectively dispose of the gravels contaminated by high-concentration uranium and secure a high level of efficiency for decontamination. In order to decontaminate the gravels which were contained in the soil contaminated by uranium and showed a higher

  6. Gravel Image Segmentation in Noisy Background Based on Partial Entropy Method

    2000-01-01

    Because of wide variation in gray levels and particle dimensions and the presence of many small gravel objects in the background, as well as corrupting the image by noise, it is difficult o segment gravel objects. In this paper, we develop a partial entropy method and succeed to realize gravel objects segmentation. We give entropy principles and fur calculation methods. Moreover, we use minimum entropy error automaticly to select a threshold to segment image. We introduce the filter method using mathematical morphology. The segment experiments are performed by using different window dimensions for a group of gravel image and demonstrates that this method has high segmentation rate and low noise sensitivity.

  7. Gravel packing dual zones in one trip reduces offshore completion time

    Brannon, D.H.; Harrison, D.T.; van Sickle, E.W.

    1991-01-01

    A single trip, dual-zone gravel pack system was used to successfully gravel pack two wells on Green Canyon platform 52 A in the Gulf of Mexico. An average 56 hours was saved on each well, representing reductions of about 25% in completion time and 26% in completion cost per well. Time-sensitive costs had the largest impact on Green Canyon 52 A final well completion cost; therefore, new technology or more efficient operations were required to minimize completion time. One way to enhance project economics was to gravel pack two separate zones in one trip. In this paper, four objectives are addressed during development of a single trip tool to gravel pack the stacked zones of the Marquette project. These were time and cost reduction, removal of loss circulation material (LCM) prior to gravel packing, zone isolation during gravel packing and use of conventional gravel placement techniques. The design requirement that all LCM (salt and/or viscous polymer pills), perforation debris and formation sand be removed from the wellbore prior to gravel packing was accomplished by incorporating a washdown feature that allows circulation at the bottom of the gravel pack assembly prior to landing in the sump packer

  8. Water quality in gravel pits in the Bratislava area

    Flakova, R.; Rohacikova, A.; Zenisova, Z.

    1999-01-01

    The gravel pits around Bratislava have an esthetic, urban and recreational function. Open water table areas are in a direct contact with the air and acquire some characteristics of the surface water. The quality of open water table is much more susceptible to pollution than that of groundwater. Wet and dry deposition, water inflow from the surrounding surface, unmanageable sewerage effluents, solid and liquid wastes, but also the water birds contribute to the pollution. The Department of Hydrogeology has monitored the water quality in six gravel pits (Cunovo, Drazdiak, Strkovec, Pasienky, Zlate Piesky, Vajnory) since 1976 with an an interruption between 1988 - 1993. Two sampling per year have been made since 1994 and after 1998 the analyses have been supplemented by Na, K, Fe, Mn, by oxygen regime parameters, by trace elements (As, Ag, Cd, Co, Cu, Cr, Hg, Ni, Pb, V, Zn) and by organic pollutants. As regards the oxygen regime, the water quality pits is very good. The anthropogenic influence is expressed mainly by the increased contents of sulfates and chlorides. Most problematic trace elements are the mercury and vanadium (Drazdiak, Zlate Piesky and Vajnory). (authors)

  9. Economy Profile of Argentina

    World Bank Group

    2017-01-01

    Doing Business 2018 is the 15th in a series of annual reports investigating the regulations that enhance business activity and those that constrain it. This economy profile presents the Doing Business indicators for Argentina. Doing Business presents quantitative indicators on business regulation and the protection of property rights that can be compared across 190 economies; for 2018 Arge...

  10. Radiation vulcanization in Argentina

    Ferenaz, Guillermo W.; Smolko, Eduardo E.

    1999-01-01

    The possibilities of using in Argentina the radiation process to vulcanize natural latex are analyzed. Experimental studies to define the irradiation conditions have been carried out and the preliminary elaboration of an irradiation device that includes the chemical reactor has been started. (author)

  11. El IDRC en Argentina

    comercio capaces de sostener el crecimiento y reducir la pobreza. ... Rosario, en Argentina, se ha convertido en un ejemplo internacional para la agricultura urbana gracias a la ... para evaluar los riesgos y beneficios de esta tecnología para ...

  12. Gravel road stabilisation of Ehnsjoevaegen, Hallstavik[Using fly ash]; Skogsbilvaegsrenovering av Ehnsjoevaegen, Hallstavik

    Macsik, Josef; Svedberg, Bo [Ecoloop, Stockholm (Sweden)

    2006-03-15

    Fly ash in geotechnical applications has stabilising, isolating, low permeability and hardening effect. Fly ash can be used in road constructions with low bearing capacity, as well as on top cover material on landfills. The aim of the project was to build a road section with fly ash stabilised gravel, based on laboratory studies, and follow up technical and environmental aspect during the first year after stabilisation. The overall aim of this project was to evaluate fly ash from Holmen Paper, Hallstavik, from technical and environmental point of view in a gravel road construction. A gravel road, Ehnsjoevaegen, was stabilised with fly ash during autumn 2004. This road was a low priority road. The fly ash stabilised road section was 1300 m long. Gravel from the road Ehnsjoevaegen was stabilised and investigated in a laboratory study. Leachability of metals and geotechnical aspects were investigated. The laboratory study showed that fly ash stabilised gravel has high shear strength, however its thawing resistance is not fully acceptable. Additives of cement or merit are needed in order to increase its thawing resistance. The actual road section is not going to be used during thawing period and no additives were used. The test road is divided into different sections including a reference section. The road stabilisation work was conducted with gravel transported to Ehnsjoevaegen from off site and not with gravel from the site. Fly ash was tipped off on a levelled road, followed by tipping of gravel. Mixing fly ash and gravel was done on site by a road scraper. After the mixing the road was gravelled with 0,1 m graded gravel. In this project the fly ash had low water content. In order to get optimal compaction water was added from a tanker supplying water before compacted with a compactor. Results from the pilot test shows that fly ash stabilised gravel can be tipped, mixed and compacted effectively. Tipping can be optimised if fly ash and gravel is mixed in a mixer

  13. The effect of coarse gravel on cohesive sediment entrapment in an annular flume

    Glasbergen, K.; Stone, M.; Krishnappan, B.; Dixon, J.; Silins, U.

    2015-03-01

    While cohesive sediment generally represents a small fraction (armour layer of the gravel bed (>16 Pa), cohesive materials trapped within the gravel bed will be entrained and transported into the Glenmore Reservoir, where sediment-associated nutrients may pose treatment challenges to the drinking water supply.

  14. Sea Dredged Gravel versus Crushed Granite as Coarse Aggregate for Self Compacting Concrete in Aggressive Environment

    Sørensen, Eigil V.; Kristensen, Lasse Frølich

    2007-01-01

    Properties of self compacting concrete (SCC) with two types of coarse aggregate - sea dredged gravel with smooth and rounded particles and crushed granite with rough and angular particles - have been studied. Sea gravel allowed a higher aggregate proportion in the concrete leading to a higher...

  15. Impact of recycled gravel obtained from low or medium concrete grade on concrete properties

    Yasser Abdelghany Fawzy

    2018-04-01

    Full Text Available This paper investigates the effect of recycled gravel obtained from low (Gl or medium (Gm concrete grade on fresh property of concrete (slump, mechanical properties (compressive-splitting tensile strength and mass transport properties (ISAT-sorptivity of concrete containing dolomite as a natural coarse aggregate. Concrete specimens were prepared with cement, water, sand and dolomite admixed with recycled gravel. The percentage of recycled gravel/dolomite was 0:100, 25:75, 50:50 and 75:25 at w/c = 0.50, 0.55 and 0.60. The effect of silica fume and bonding admixture at w/c = 0.55 on concrete properties were also considered. The results indicated that, increasing the percentage of recycled gravel/dolomite led to decreasing the slump. All mechanical properties of concrete discussed were inversely affected by increasing percentage of recycled gravel/dolomite from low and medium concrete. Adding 10% SF or bonding admixture increased the mechanical properties of concrete. Mass transport properties of concrete (ISAT-sorptivity were enhanced by decreasing the percentage of recycled gravel/dolomite. The optimum percentage of recycled gravel/dolomite = 25%. Keywords: Recycled gravel, Concrete, Silica fume, Compressive strength, Mass transport

  16. Evaluation of an ion adsorption method to estimate intragravel flow velocity in salmonid spawning gravels

    James L. Clayton; John G. King; Russell F. Thurow

    1996-01-01

    Intragravel water exchange provides oxygenated water, removes metabolic waste, and is an essential factor in salmonid embryo survival. Measurements of intragravel flow velocity have been suggested as an index of gravel quality and also as a useful predictor of fry emergence; however, proposed methods for measuring velocity in gravel are problematic. We evaluate an ion...

  17. Argentina set for privatization

    Chynoweth, E.

    1992-01-01

    Buyers are lining up for Argentina's two big state-controlled petrochemical groups, Buenos Aires-based Petroquimica General Mosconi (PGM) and Petroquimica Bahia Blance (PBB). However, feedstock supply contracts with government-owned oil group Yacientos Petroliferos Fiscales (YPG) and gas group Gas del Estado hold the key to both sales. Shell Compania Argentina Petroleo SA (CAPSA), Perez Companc, and Global Petroleum have already bought PGM tender documentation. Shell says it will bid for PGM if the feedstock contract with YPF is acceptable. In addition to price and volume, Shell says the length is critical; it wants a 15-year deal, but would settle for 11. YPF initially sought a five-year contract. PGM, which produces 300,000 m.t./year of aromatics, plus oxo alcohols, methanol, and methyl tert-butyl ether, has sales of $150 million/year

  18. Crisis cambiaria en Argentina

    Féliz, Mariano

    2009-01-01

    El análisis de la articulación entre el proceso de valorización exitosa de capital y la tendencia a la desvalorización de las mercancías se aplica a una de las manifestaciones de la crisis argentina: la devaluación del peso. Se estudia la relación entre la determinación del tipo de cambio y la valorización del capital. Se discuten las tendencias concretas de la economía argentina en la década de 1990 y se muestra cómo la devaluación de 2001-2002 fue producto necesario del propio proceso de va...

  19. Fruit fly eradication: Argentina

    2003-01-01

    Fruit exports account for 9% of Argentina's total agricultural exports and generate annually close to $450 million. This could be increased but for fruit flies that cause damage equivalent to 15% to 20% of present production value of fruit and also deny export access to countries imposing quarantine barriers. The Department of Technical Co-operation is sponsoring a programme, with technical support from the Joint FAO/IAEA Division, to eradicate the Mediterranean fruit fly using the Sterile Insect Technique (SIT). (IAEA)

  20. The air flow and heat transfer in gravel embankment in permafrost areas

    JIANG Fan; LIU Shi; WANG Haigang; CHEN Huanzhuo

    2004-01-01

    A comparative numerical investigation of transient temperature profile and pore-air velocities in horizontal rock block embankments are conducted using the "gravels model", in which the embankment is composed of stones and air, and the "porous media model" respectively. As the velocities from the "gravels model" directly reflect the true flow of air and winter-time convection, in this paper it can be concluded that computational results from the "gravels model"are superior to the "porous media model". In addition, the "gravels model" has the advantages of reflecting the effect of the dimensions and collocation of gravels upon the temperature fields.Therefore, the computation of the gravels embankment is mainly based on the gravels model.Simulation results show that in summer, a clockwise circulation of the pore-air extends throughout most of the embankment. However its motion is very weak that results in relatively straight horizontal isotherm lines. And heat transfer is mainly maintained through conduction. But in winter, the pore-air velocities are higher and multiple vortexes are formed in the embankment.Natural convection then becomes the dominant influence on the isotherm shapes within the embankment. The isotherms are complex and alternative upward and downward flowing plumes exist. The winter-time convection can further reduce the temperature of the foundation soil beneath the gravel embankment. In addition, the effects of the gravel dimensions within the embankment have been analyzed and compared in the gravels model. It shows that in winter, large stones, e.g. 200 mm, lead to stronger vortexes than those of small stones, say 60 mm. Consequently, the zone of low-temperature beneath the large-stone embankment extends deeper into the ground.

  1. Argentina [Country report

    Ferreyra, R.

    2005-01-01

    The airborne geophysical surveys developed in Argentina are described. They have got more than 500.000 km 2 acquiring data for U, Th, K and total background activity. Other types of published data are also mentioned (satellite imagery, seismic hazard, climate, soil distributions, etc.). The availability of maps with the abundances of elements analyzed at the country and also at laboratories from Canada is described, as well as data of analysis of several elements at two study areas proposed at the outset of the project. The availability of process rate data and epidemiological data is also explained. Argentina intended fully to participate in the CRP at the outset of the project. Due, however, to external resource constraints imposed on the participating organization (Comision Nacional de Energia Atomica, CNEA), the level of participation had to be significantly reduced. Nonetheless, in the first period of the CRP, Argentina undertook to collate existing geological and geochemical information within the country, and began to define potential areas for site specific natural systems safety indicator studies. (author)

  2. de la sociedad argentina

    Diego Galeano

    2007-01-01

    Full Text Available Este artículo trata sobre un período de la historia argentina en el cual la "mirada médica", a través de un grupo de prestigiosos intelectuales, se convirtió en una clave de interpretación de la sociedad argentina. El análisis gira en torno a la obra de uno de los médicos higienistas más influyentes, José María Ramos Mejía, deteniéndose especialmente en su libro más famoso: Las multitudes argentinas (1899. La hipótesis principal que recorre el texto es la siguiente: la medicalización de la sociedad, acentuada luego de las epidemias de cólera y fiebre amarilla de mediados del siglo XIX, ofreció a las elites públicas la posibilidad de construir dominios legítimos de intervención estatal. Intromisiones del Estado en la vida privada que, además de ser algo resistidas por la población, entraban en tensión con los principios teóricos del liberalismo que los propios miembros de la elite defendían.

  3. Mine drivage in hydraulic mines

    Ehkber, B Ya

    1983-09-01

    From 20 to 25% of labor cost in hydraulic coal mines falls on mine drivage. Range of mine drivage is high due to the large number of shortwalls mined by hydraulic monitors. Reducing mining cost in hydraulic mines depends on lowering drivage cost by use of new drivage systems or by increasing efficiency of drivage systems used at present. The following drivage methods used in hydraulic mines are compared: heading machines with hydraulic haulage of cut rocks and coal, hydraulic monitors with hydraulic haulage, drilling and blasting with hydraulic haulage of blasted rocks. Mining and geologic conditions which influence selection of the optimum mine drivage system are analyzed. Standardized cross sections of mine roadways driven by the 3 methods are shown in schemes. Support systems used in mine roadways are compared: timber supports, roof bolts, roof bolts with steel elements, and roadways driven in rocks without a support system. Heading machines (K-56MG, GPKG, 4PU, PK-3M) and hydraulic monitors (GMDTs-3M, 12GD-2) used for mine drivage are described. Data on mine drivage in hydraulic coal mines in the Kuzbass are discussed. From 40 to 46% of roadways are driven by heading machines with hydraulic haulage and from 12 to 15% by hydraulic monitors with hydraulic haulage.

  4. The industrial nuclear fuel cycle in Argentina

    Koll, J.H.; Kittl, J.E.; Parera, C.A.; Coppa, R.C.; Aguirre, E.J.

    1977-01-01

    The nuclear power program of Argentina for the period 1976-85 is described, as a basis to indicate fuel requirements and the consequent implementation of a national fuel cycle industry. Fuel cycle activities in Argentina were initiated as soon as 1951-2 in the prospection and mining activities through the country. Following this step, yellow-cake production was initiated in plants of limited capacity. National production of uranium concentrate has met requirements up to the present time, and will continue to do so until the Sierra Pintada Industrial Complex starts operation in 1979. Presently, there is a gap in local production of uranium dioxide and fuel elements for the Atucha power station, which are produced abroad using Argentine uranium concentrate. With its background, the argentine program for the installation of nuclear fuel cycle industries is described, and the techno-economical implications considered. Individual projects are reviewed, as well as the present and planned infrastructure needed to support the industrial effort [es

  5. XBeach-G: a tool for predicting gravel barrier response to extreme storm conditions

    Masselink, Gerd; Poate, Tim; McCall, Robert; Roelvink, Dano; Russell, Paul; Davidson, Mark

    2014-05-01

    Gravel beaches protect low-lying back-barrier regions from flooding during storm events and their importance to society is widely acknowledged. Unfortunately, breaching and extensive storm damage has occurred at many gravel sites and this is likely to increase as a result of sea-level rise and enhanced storminess due to climate change. Limited scientific guidance is currently available to provide beach managers with operational management tools to predict the response of gravel beaches to storms. The New Understanding and Prediction of Storm Impacts on Gravel beaches (NUPSIG) project aims to improve our understanding of storm impacts on gravel coastal environments and to develop a predictive capability by modelling these impacts. The NUPSIG project uses a 5-pronged approach to address its aim: (1) analyse hydrodynamic data collected during a proto-type laboratory experiment on a gravel beach; (2) collect hydrodynamic field data on a gravel beach under a range of conditions, including storm waves with wave heights up to 3 m; (3) measure swash dynamics and beach response on 10 gravel beaches during extreme wave conditions with wave heights in excess of 3 m; (4) use the data collected under 1-3 to develop and validate a numerical model to model hydrodynamics and morphological response of gravel beaches under storm conditions; and (5) develop a tool for end-users, based on the model formulated under (4), for predicting storm response of gravel beaches and barriers. The aim of this presentation is to present the key results of the NUPSIG project and introduce the end-user tool for predicting storm response on gravel beaches. The model is based on the numerical model XBeach, and different forcing scenarios (wave and tides), barrier configurations (dimensions) and sediment characteristics are easily uploaded for model simulations using a Graphics User Interface (GUI). The model can be used to determine the vulnerability of gravel barriers to storm events, but can also be

  6. Web Mining

    Fürnkranz, Johannes

    The World-Wide Web provides every internet citizen with access to an abundance of information, but it becomes increasingly difficult to identify the relevant pieces of information. Research in web mining tries to address this problem by applying techniques from data mining and machine learning to Web data and documents. This chapter provides a brief overview of web mining techniques and research areas, most notably hypertext classification, wrapper induction, recommender systems and web usage mining.

  7. Text Mining.

    Trybula, Walter J.

    1999-01-01

    Reviews the state of research in text mining, focusing on newer developments. The intent is to describe the disparate investigations currently included under the term text mining and provide a cohesive structure for these efforts. A summary of research identifies key organizations responsible for pushing the development of text mining. A section…

  8. Surface mining

    Robert Leopold; Bruce Rowland; Reed Stalder

    1979-01-01

    The surface mining process consists of four phases: (1) exploration; (2) development; (3) production; and (4) reclamation. A variety of surface mining methods has been developed, including strip mining, auger, area strip, open pit, dredging, and hydraulic. Sound planning and design techniques are essential to implement alternatives to meet the myriad of laws,...

  9. Uranium mining

    Lange, G.

    1975-01-01

    The winning of uranium ore is the first stage of the fuel cycle. The whole complex of questions to be considered when evaluating the profitability of an ore mine is shortly outlined, and the possible mining techniques are described. Some data on uranium mining in the western world are also given. (RB) [de

  10. Argentina: a mature urbanization pattern.

    Rofman, A B

    1985-02-01

    "This article describes the historical development of Argentina's cities, pointing out the traditional dominance of the 'centre-litoral' region and...[of] Buenos Aires. Recent trends such as the population increase in the southern region are described and demographic trends are related to economic developments. The article concludes by examining Argentina's contemporary urban patterns, including the current low rate of urbanization." excerpt

  11. Argentina's radioactive waste disposal policy

    Palacios, E.

    1986-01-01

    The Argentina policy for radioactive waste disposal from nuclear facilities is presented. The radioactive wastes are treated and disposed in confinement systems which ensure the isolation of the radionucles for an appropriate period. The safety criteria adopted by Argentina Authorities in case of the release of radioactive materials under normal conditions and in case of accidents are analysed. (M.C.K.) [pt

  12. Delineation of gravel-bed clusters via factorial kriging

    Wu, Fu-Chun; Wang, Chi-Kuei; Huang, Guo-Hao

    2018-05-01

    Gravel-bed clusters are the most prevalent microforms that affect local flows and sediment transport. A growing consensus is that the practice of cluster delineation should be based primarily on bed topography rather than grain sizes. Here we present a novel approach for cluster delineation using patch-scale high-resolution digital elevation models (DEMs). We use a geostatistical interpolation method, i.e., factorial kriging, to decompose the short- and long-range (grain- and microform-scale) DEMs. The required parameters are determined directly from the scales of the nested variograms. The short-range DEM exhibits a flat bed topography, yet individual grains are sharply outlined, making the short-range DEM a useful aid for grain segmentation. The long-range DEM exhibits a smoother topography than the original full DEM, yet groupings of particles emerge as small-scale bedforms, making the contour percentile levels of the long-range DEM a useful tool for cluster identification. Individual clusters are delineated using the segmented grains and identified clusters via a range of contour percentile levels. Our results reveal that the density and total area of delineated clusters decrease with increasing contour percentile level, while the mean grain size of clusters and average size of anchor clast (i.e., the largest particle in a cluster) increase with the contour percentile level. These results support the interpretation that larger particles group as clusters and protrude higher above the bed than other smaller grains. A striking feature of the delineated clusters is that anchor clasts are invariably greater than the D90 of the grain sizes even though a threshold anchor size was not adopted herein. The average areal fractal dimensions (Hausdorff-Besicovich dimensions of the projected areas) of individual clusters, however, demonstrate that clusters delineated with different contour percentile levels exhibit similar planform morphologies. Comparisons with a

  13. Ecological restoration of Central European mining sites: a summary of a multi-site analysis

    Prach, K.; Rehounkova, K.; Rehounek, J.; Konvalinkova, P. [University of South Bohemia, Ceske Budejovice (Czech Republic)

    2011-07-01

    Sites disturbed by mining were surveyed in the Czech Republic, central Europe. The sites included spoil heaps from coal mining, sand and gravel pits, extracted peatlands and stone quarries. The following main conclusions emerged: I) potential for spontaneous succession to be used in restoration projects is between 95 and 100% of the total area disturbed; ii) mining sites, if mining is properly designed and then the sites are left to spontaneous succession, often act as refugia for endangered and retreating organisms, and may contribute substantially to local biodiversity.

  14. Mining Waste Classification and Quantity of Non-Metal Minesin Slovenia

    Ana Burger

    2007-06-01

    Full Text Available Mining is an important human activity that creates wealth and supplies materials for maintaining standard of living and further human development. However, mining has also negative impacts on the environment and society. One of them is the production of mining waste throughout the entire mining cycle, in particular in the mine development and operation /production stage.Due to the EU Directive 2006/21/EC on the management of waste from the extractive industries and its implementation in Member state, estimation on quality and quantity of mining waste from active non-metal mines in Slovenia was carried out. In the selected mines mining and processing was closely examined. With material flow analysis quantity and characteristics of mining waste were defined for several mines of different commodities.Data on mining waste were afterwards generalized in order to get an overall country evaluation on mining waste “production” of non-metal mines.Mining waste as a result of mining and beneficiation processes in non-metal mines of Slovenia is either inert or non-hazardous. Most of the mining waste is used for mine reclamation running simultaneously with the production phase. The largest amounts of mining waste per unit produced are created in dimension stone industry. Since the dimensionstone production is small, the waste amount is negligible. Large quantities of mining waste are produced in crushed stone and, sand and gravel operations, because aggregate production is pretty large with regard to other non-metals production in Slovenia. We can therefore conclude that large quantities of mining waste from non-metal mines, which are mostly used in reclamation and for side products, do not represent danger to the environment.

  15. Economic Valuation of Sand and Gravel in Davao del Norte, Philippines

    Tamayo, Adrian; Tagalo, Romulo

    2016-01-01

    The study aims to quantify the economic value of the sand and gravel which is deemed as a non-renewable resource. A survey was conducted to extract the consumer surplus of the households, also construct the demand equation for the resource. With the demand equation for sand and gravel at , the consumer surplus was estimated at P8271. Using the economic valuation technique, the economic value of sand and gravel was estimated at P729,568,368. Thus, a very high value imputed on the environmenta...

  16. Efficiency of Cleanup of Ra-226 Contaminated Gravel Assayed by LSC and TL Dosimetry

    Mamoon, A.; Abulfaraj, W.H.; Kamal, S.M.; Sohsah, M.A.

    1999-01-01

    The present study concerns itself with decontamination of gravel that had been contaminated with Ra-226 from natural origins. Aqueous solutions of different compositions including water, and various concentrations of CaCl 2 and BaCl 2 were used to leach the contaminated gravel. The leaching experiments were carried out in glass columns. In some leaching experiments a sample of a common brand of sandy soil (fine sand with traces of silt )was placed below the gravel to test the binding capacity (sorption) of this soil for the leached Ra-226

  17. Radiological characteristic of an area reclaimed by means of an ash-gravel power plant wastes

    Zak, A.; Biernacka, M.; Kusyk, M.; Mamont-Ciesla, K.; Florowska, K.

    2002-01-01

    A sand excavation after extraction of gravel and sand was filled with an ash-gravel mix. The mix was covered with shielding layers of clay and soil and grass was cultivated on it. Investigations of radiological characteristic such as: gamma radiation dose rate, radon concentration in soil air and radionuclide concentration in the ground were carried out in the both areas reclaimed one and in the vicinity of it. Radon exhalation coefficients were determined for uncovered ash-gravel mix layer, the shielding soil layer and for the ground in the vicinity. Analysis of the results revealed that the reclaimed area can be used for building development. (author)

  18. RERTR activities in Argentina

    Adelfang, P.; Alvarez, L.; Pasqualini, E.

    2002-01-01

    The Atomic Energy Commission of Argentina has been an active participant of the RERTR program since 1978. An important milestone of the Argentinean RERTR program was the development and manufacturing at industrial scale of U 3 O 8 dispersed fuel and its subsequent application to the conversion of the RA-3 reactor core to LEU fuel. More recently, our activities were focused on the development of U 3 Si 2 fuel with a density of 4.8 gU/cm 3 and the improvement of the manufacturing process of this type of fuel. The program to qualify CNEA as a supplier U 3 Si 2 dispersed fuels is scheduled to finalize by mid 2003. To hasten this program the main research reactor of Argentina, the RA3, raised its power from 5 MW to 8 Mw in October this year. This is an intermediate step in the program to increase RA-3 power to 10 MW Currently, one of the main objectives is to develop and qualify the technology for the production of high-density LEU fuel elements using U-Mo alloy. An original way to produce U-Mo powder (the HMD process) was developed and its being upgraded to plant scale production. Another significant progress was the development of LEU targets for the production of 99 Mo, in the form of miniplates prepared with dispersed LEU U-Al x . The shipment to USA of 207 MTR spent fuels containing US origin highly enriched uranium, successfully carried out in the end of 2000, is another remarkable achievement of the Argentinean RERTR program. This activity was carried out in the framework of the United States Foreign Research Reactor Spent Nuclear Fuel Acceptance Program. The fuels were fabricated in Argentina and used in the RA-3 reactor from 1968 to 1987. The inventory of the shipped HEU spent fuel consisted in 166 standard assemblies and 41 control assemblies. (author)

  19. Contract Mining versus Owner Mining

    Owner

    mining companies can concentrate on their core businesses while using specialists for ... 2 Definition of Contract and Owner. Mining ... equipment maintenance, scheduling and budgeting ..... No. Region. Amount Spent on. Contract Mining. ($ billion). Percent of. Total. 1 ... cost and productivity data based on a large range.

  20. SEISMIC VELOCITY DETERMINATION IN GRAVEL AND SANDS USING PIEZOCRYSTALS

    Santamarina Juan Carlos

    2008-06-01

    Full Text Available The exact determination of seismic waves' propagation velocities has great importance in the geotechnics due to from that it is possible to determine, among other parameters, the dynamic ones: Elasticity E, Rigidity G, Poisson !, compressibility B; as well as to reach a knowledge on the stress-strain behavior for the studied soil samples. The seismic waves transmission considered in tests at laboratory scale carried out in the present work is a phenomenon that produces very small deformation, and so doesn't disturb the material. This allows
    to apply the results in a more general scale to study the behavior of soils in situ and to predict their answer to stress.
    With the purpose to study the response of particulate material subjected to seismic excitements at small scale, samples of gravels and sands were successively introduced in an odometric cell, exciting them with impulsive signals and registering the corresponding seismograms through general purpose piezoelectric transducers embedded in ends of the cell.
    The distance source-receiver was interval increased, which enabled, from the corresponding regression straight lines, to calculate in precise form the propagation velocities (for P waves.
    The tests were carried out in samples of dry alluvial soil with three different grain sizes. The respective frequency spectra of the signals were determined for two packing modes: loose and compact, what added information on the medium characteristics.

  1. Roughness coefficient and its uncertainty in gravel-bed river

    Ji-Sung Kim

    2010-06-01

    Full Text Available Manning's roughness coefficient was estimated for a gravel-bed river reach using field measurements of water level and discharge, and the applicability of various methods used for estimation of the roughness coefficient was evaluated. Results show that the roughness coefficient tends to decrease with increasing discharge and water depth, and over a certain range it appears to remain constant. Comparison of roughness coefficients calculated by field measurement data with those estimated by other methods shows that, although the field-measured values provide approximate roughness coefficients for relatively large discharge, there seems to be rather high uncertainty due to the difference in resultant values. For this reason, uncertainty related to the roughness coefficient was analyzed in terms of change in computed variables. On average, a 20% increase of the roughness coefficient causes a 7% increase in the water depth and an 8% decrease in velocity, but there may be about a 15% increase in the water depth and an equivalent decrease in velocity for certain cross-sections in the study reach. Finally, the validity of estimated roughness coefficient based on field measurements was examined. A 10% error in discharge measurement may lead to more than 10% uncertainty in roughness coefficient estimation, but corresponding uncertainty in computed water depth and velocity is reduced to approximately 5%. Conversely, the necessity for roughness coefficient estimation by field measurement is confirmed.

  2. Case study - Argentina

    Diaz, E.

    1986-01-01

    Antecedents and experience of nuclear activities in Argentina; the Atomic Energy Commission (CNEA). First development and research activities. Research reactors and radioisotopes plants. Health physics and safety regulations. - Feasibility studies for the first nuclear power plant. Awarding the first plant CNA I (Atucha I). Relevant data related to the different project stages. Plant performance. - Feasibility study for the second nuclear power plant. Awarding the second plant CNE (Central Nuclear Embalse). Relevant data related to established targets. Differences compared with the first station targets. Local participation. Plant performance. (orig./GL)

  3. Utilization of washery dirt and mine refuse

    Leininger, D; Schieder, T

    1975-10-02

    Washery dirt and mine refuse may be used without processing as road ballast, embankments and dykes, and for filling gravel pits and subsidence areas. The properties required in road ballast are outlined. For the top portions of embankments and for frost protection layers, washery dirt must be processed to remove particles of the wrong size. Methods of heat treatment are listed, and the chemical composition of the dirt is discussed. Because of its different chemical composition, large particles are preferable to fine dirt for some applications, even if they have to be crushed. Tree planting experiments on spoilbanks are described.

  4. Activities with Argentina

    1999-01-01

    In 1989, the US Department of Energy (DOE) responded to the need to redirect resources from weapons production to environmental restoration and waste management by establishing the Office of Environmental Management (EM) and delegated to this office the responsibility of cleaning up the US nuclear weapons complex. Now in its eight year, EM's mission has three central facets: (1) to assess, remediate, and monitor contaminated sites and facilities; (2) to store, treat, and dispose of waste from past and current operations; and (3) to develop and implement innovative technologies for environmental cleanup. To this end, EM has established domestic and international cooperative technology development programs, including one with the Republic of Argentina. Cooperating with Argentine scientific institutes and industries meets US cleanup objectives by: (1) identifying and accessing Argentine EM-related technologies, thereby leveraging investments and providing cost-savings; (2) improving access to technical information, scientific expertise, and technologies applicable to EM needs; and (3) fostering the development of innovative environmental technologies by increasing US private sector opportunities in Argentina in EM-related areas

  5. QUBIC in Argentina

    García, B.; Harari, D.; Etchegoyen, A.; Medina, M. C.; Romero, G. E.; Qubic Collaboration

    2017-10-01

    QUBIC (QU Bolometric Interferometer for Cosmology) is an experimental cosmology project to measure the modes in the polarization of the cosmic background radiation (CBR), the fossil relic that reveals the properties at the Universe 380,000 years after the Planck Era. Discovery of the CBR in 1964 and measurement of tiny temperature anisotropies in 1992 were major breakthroughs in our understanding of the Universe. The next challenge is to measure the polarization of the CBR accurately enough to detect modes that would reveal the existence of primordial gravitational waves produced in the first stages of the Planck Era and probe inflation theory, that assumes an accelerated expansion during the first seconds. The mode signal is however extremely weak and its measurement requires complex instruments. The QUBIC collaboration has developed the concept of interferometric bolometry, that brings together the sensitivity of bolometric detectors with the control of systematic effects provided by interferometry. QUBIC is an international collaboration involving several universities and laboratories in France, Italy, United Kingdom and USA. Recently, Argentina has suggested Alto Chorrillo (Salta), as candidate site for the installation of the experiment, next to the LLAMA site. Here we describe the scientific objectives and the main features of the experiment and we detail the process through which the international collaboration decided to install in Argentina its first module as well as the challenges for our country in this project.

  6. RERTR activities in Argentina

    Adelfang, P.; Alvarez, L.; Boero, N.; Calabrese, R.; De La Fuente, M.; Echenique, P.; Markiewicz, M.; Pasqualini, E.; Perez, A.; Piazza, A.; Ruggirello, G.; Taboada, H.

    2000-01-01

    The Atomic Energy Commission of Argentina has been involved in the Reduced Enrichment for Research and Test Reactors Program since 1978. The most relevant milestones of the program, regarding fuel R and D activities, were the development and manufacturing at industrial scale of U 3 O 8 dispersed fuel assemblies and the conversion of the RA-3 reactor core to LEU fuel. More recently, the activities were focused in the development of high density U 3 Si 2 fuel with a density of 4.8 gU/cm 3 and the improvement of the manufacturing process of U 3 Si 2 powder. Currently one of the main objectives is to develop and qualify the technology for the production of high-density LEU fuel elements using U-Mo alloy. Several alternative ways to obtain U-Mo powder are under development with the aim of evaluating plant scale production and costs. To boost this program the main research reactor of Argentina, the RA-3, will be upgraded to 10 MW early in 2001 and the hot cells at the Ezeiza Atomic Center are fully operational after important investments. Significant progresses were also carried out in the development of LEU targets for the production of Mo 99 . Experimental work has demonstrated the feasibility of the manufacturing and radiochemical processing of miniplate targets prepared with dispersed UAl x , maintaining the geometry and the alkaline processing of the HEU targets used so far. (author)

  7. Population structure in Argentina.

    Marina Muzzio

    Full Text Available We analyzed 391 samples from 12 Argentinian populations from the Center-West, East and North-West regions with the Illumina Human Exome Beadchip v1.0 (HumanExome-12v1-A. We did Principal Components analysis to infer patterns of populational divergence and migrations. We identified proportions and patterns of European, African and Native American ancestry and found a correlation between distance to Buenos Aires and proportion of Native American ancestry, where the highest proportion corresponds to the Northernmost populations, which is also the furthest from the Argentinian capital. Most of the European sources are from a South European origin, matching historical records, and we see two different Native American components, one that spreads all over Argentina and another specifically Andean. The highest percentages of African ancestry were in the Center West of Argentina, where the old trade routes took the slaves from Buenos Aires to Chile and Peru. Subcontinentaly, sources of this African component are represented by both West Africa and groups influenced by the Bantu expansion, the second slightly higher than the first, unlike North America and the Caribbean, where the main source is West Africa. This is reasonable, considering that a large proportion of the ships arriving at the Southern Hemisphere came from Mozambique, Loango and Angola.

  8. [Effects of gravel mulch technology on soil erosion resistance and plant growth of river flinty slope].

    Zhu, Wei; Xie, San-Tao; Ruan, Ai-Dong; Bian, Xun-Wen

    2008-03-01

    Aiming at the technical difficulties such as the stability and water balance in the ecological rehabilitation of river flinty slope, a gravel mulch technology was proposed, with the effects of different gravel mulch treatments on the soil anti-erosion capacity, soil water retention property, and plant growth investigated by anti-erosion and pot experiments. The results showed that mulching with the gravels 1.5-2 cm in size could obviously enhance the soil anti-erosion capacity, soil water retention property and plant biomass, but no obvious differences were observed between the mulch thickness of 5 cm and 8 cm. It was indicated that mulching with the gravels 1.5-2 cm in size and 5 cm in thickness was an effective and economical technology for the ecological rehabilitation of river flinty slope.

  9. Influence of vegetation and gravel mesh on the tertiary treatment of wastewater from a cosmetics industry.

    Vlyssides, Apostolos G; Mai, Sofia T H; Barampouti, Elli Maria P; Loukakis, Haralampos N

    2009-07-01

    To estimate the influence of gravel mesh (fine and coarse) and vegetation (Phragmites and Arundo) on the efficiency of a reed bed, a pilot plant was included after the wastewater treatment plant of a cosmetic industry treatment system according to a 22 factorial experimental design. The maximum biochemical oxygen demand (BOD5), chemical oxygen demand (COD) and total phosphorous (TP) reduction was observed in the reactor, where Phragmites and fine gravel were used. In the reactor with Phragmites and coarse gravel, the maximum total Kjeldahl nitrogen (TKN) and total suspended solids (TSS) reduction was observed. The maximum total solids reduction was measured in the reed bed, which was filled with Arundo and coarse gravel. Conclusively, the treatment of a cosmetic industry's wastewater by reed beds as a tertiary treatment method is quite effective.

  10. Analytical Technique of Gravel Propensity in Coal pit

    Kovačič, Blaž; Zupančič, Borislav; Potočnik, Damir

    2011-01-01

    In terms of surrounding rock with rock burst tendency in coal mine, the rock burst occur when elastic energy accumulation of rock mass system for rock mass deformation reached the limit of rock mass energy storage, and the condition that the factors effected elastic energy accumulation needed to meet can be laid out. The rock burst tendency analysis can be defined as a progress as following: making sure the stress condition of surrounding rock and the. For the purpose of forecasting rock burs...

  11. Macroinvertebrate community responses to gravel augmentation in a high-gradient, Southeastern regulated river

    McManamay, Ryan A [ORNL; Orth, Dr. Donald J [Virginia Polytechnic Institute and State University; Dolloff, Dr. Charles A [United States Department of Agriculture (USDA), United States Forest Service (USFS) and Virginia Pol

    2013-01-01

    Sediment transport, one of the key processes of river systems, is altered or stopped by dams, leaving lower river reaches barren of sand and gravel, both of which are essential habitat for fish and macroinvertebrates. One way to compensate for losses in sediment is to supplement gravel to river reaches below impoundments. Because gravel addition has become a widespread practice, it is essential to evaluate the biotic response to restoration projects in order to improve the efficacy of future applications. The purpose of our study was to evaluate the response of the macroinvertebrate community to gravel addition in a high-gradient, regulated river in western North Carolina. We collected benthic macroinvertebrate samples from gravel-enhanced areas and unenhanced areas for 1 season before gravel addition, and for 4 seasons afterwards. Repeated measures multivariate analysis of variance indicated that the responses of macroinvertebrates to gravel addition were generally specific to individual taxa or particular functional feeding groups and did not lead to consistent patterns in overall family richness, diversity, density, or evenness. Non-metric multi-dimensional scaling showed that shifts in macroinvertebrate community composition were temporary and dependent upon site conditions and season. Correlations between macroinvertebrate response variables and substrate microhabitat variables existed with or without the inclusion of data from enhanced areas, which suggests that substrate-biotic relationships were present before gravel addition. A review of the current literature suggests that the responses of benthic macroinvertebrates to substrate restoration are inconsistent and dependent upon site conditions and the degree habitat improvement of pre-restoration site conditions.

  12. Image analysis to measure sorting and stratification applied to sand-gravel experiments

    Orrú, C.

    2016-01-01

    The main objective of this project is to develop new measuring techniques for providing detailed data on sediment sorting suitable for sand-gravel laboratory experiments. Such data will be of aid in obtaining new insights on sorting mechanisms and improving prediction capabilities of morphodynamic models. Two measuring techniques have been developed. The first technique is aimed at measuring the size stratification of a sand-gravel deposit through combining image analysis and a sediment remov...

  13. Gravel-bed river floodplains are the ecological nexus of glaciated mountain landscapes

    Hauer, F. Richard; Locke, Harvey; Dreitz, Victoria; Hebblewhite, Mark; Lowe, Winsor; Muhlfeld, Clint C.; Nelson, Cara; Proctor, Michael F.; Rood, Stewart B.

    2016-01-01

    Gravel-bed river floodplains in mountain landscapes disproportionately concentrate diverse habitats, nutrient cycling, productivity of biota, and species interactions. Although stream ecologists know that river channel and floodplain habitats used by aquatic organisms are maintained by hydrologic regimes that mobilize gravel-bed sediments, terrestrial ecologists have largely been unaware of the importance of floodplain structures and processes to the life requirements of a wide variety of species. We provide insight into gravel-bed rivers as the ecological nexus of glaciated mountain landscapes. We show why gravel-bed river floodplains are the primary arena where interactions take place among aquatic, avian, and terrestrial species from microbes to grizzly bears and provide essential connectivity as corridors for movement for both aquatic and terrestrial species. Paradoxically, gravel-bed river floodplains are also disproportionately unprotected where human developments are concentrated. Structural modifications to floodplains such as roads, railways, and housing and hydrologicaltering hydroelectric or water storage dams have severe impacts to floodplain habitat diversity and productivity, restrict local and regional connectivity, and reduce the resilience of both aquatic and terrestrial species, including adaptation to climate change. To be effective, conservation efforts in glaciated mountain landscapes intended to benefit the widest variety of organisms need a paradigm shift that has gravel-bed rivers and their floodplains as the central focus and that prioritizes the maintenance or restoration of the intact structure and processes of these critically important systems throughout their length and breadth.

  14. Activities of the Main Studies and Designing Bureau for Mines in export of technical experience and international cooperation

    Danielak, Z

    1985-07-01

    The Main Studies and Designing Bureau for Mines in Poland consists of 3 units: the Mine Design Bureau in Katowice (leading unit) and Mine Design Bureaus in Cracow and Katowice. There are 2200 employees (75% specialists) in 3 units. The Bureau is the leading agency for coal mine design and mine modernization in Poland. In 35 years the Bureau has developed the design of 25 coal mines in Poland, the design of more than 100 mining levels, and modernization projects for more than 50 coal mines. The Bureau specializes in programs for coal district development, mine design and mine modernization. It has developed the design of coal mines and coal preparation plants in the following countries: Albania, China, Mongolia, Vietnam, Argentina, Colombia, Canada, Colombia, India, Mexico, Peru and Venezuela. Prospects for increasing exports by the Bureau are discussed.

  15. Research reactors in Argentina

    Carlos Ruben Calabrese

    1999-01-01

    Argentine Nuclear Development started in early fifties. In 1957, it was decided to built the first a research reactor. RA-1 reactor (120 kw, today licensed to work at 40 kW) started operation in January 1958. Originally RA-1 was an Argonaut (American design) reactor. In early sixties, the RA-1 core was changed. Fuel rods (20% enrichment) was introduced instead the old Argonaut core design. For that reason, a critical facility named RA-0 was built. After that, the RA-3 project started, to build a multipurpose 5 MW nuclear reactor MTR pool type, to produce radioisotopes and research. For that reason and to define the characteristics of the RA-3 core, another critical facility was built, RA-2. Initially RA-3 was a 90 % enriched fuel reactor, and started operation in 1967. When Atucha I NPP project started, a German design Power Reactor, a small homogeneous reactor was donated by the German Government to Argentina (1969). This was RA-4 reactor (20% enrichment, 1W). In 1982, RA-6 pool reactor achieved criticality. This is a 500 kW reactor with 90% enriched MTR fuel elements. In 1990, RA-3 started to operate fueled by 20% enriched fuel. In 1997, the RA-8 (multipurpose critical facility located at Pilcaniyeu) started to operate. RA-3 reactor is the most important CNEA reactor for Argentine Research Reactors development. It is the first in a succession of Argentine MTR reactors built by CNEA (and INVAP SE ) in Argentina and other countries: RA-6 (500 kW, Bariloche-Argentina), RP-10 (10MW, Peru), NUR (500 kW, Algeria), MPR (22 MW, Egypt). The experience of Argentinian industry permits to compete with foreign developed countries as supplier of research reactors. Today, CNEA has six research reactors whose activities have a range from education and promotion of nuclear activity, to radioisotope production. For more than forty years, Argentine Research Reactors are working. The experience of Argentine is important, and argentine firms are able to compete in the design and

  16. History of radiobiology in Argentina

    Mayo, Jose

    2004-01-01

    Radiobiology is a multidisciplinary science dealing with ionising radiation effects on biological material. The history of Radiobiology begins in Germany and France around 1886. Radiobiology was introduced in Argentina in 1926 at the Institute of Oncology Angel H. Roffo as a biomedical research branch. Later on in 1957 was incorporated at the National Atomic Energy Commission (CNEA) of Argentina as a result of the newly started nuclear activities in Argentina. Prior that time no Radiobiology research existed in Argentina. To fill this need a Project to create new laboratories was elaborated by the CNEA. New laboratories in Radiobiodosimetry, Cellular Radiobiology, Radiopathology, Radiomicrobiology, Genetics and Somatic Effects were created. Human resources on different areas of Radiobiology were formed with the assistance of IAEA. With professional and technical personnel specialized in Radiobiology at the beginning of the 1970 decade, the transference of fundamental and applied research to others laboratories started. (author)

  17. The health crisis in Argentina.

    Escudero, José Carlos

    2003-01-01

    The health crisis in Argentina is part of the larger crisis that has resulted from a collapse in the country's economic and political systems. After a brief review of the country's history over the last century, from international success story to economic failure, the author explains the health crisis in particular and the social crisis in general in terms of failed neoliberal policies imposed on Argentina by the United States and International Monetary Fund through the mediation of the country's political class.

  18. Operating practical experience at Argentina

    Quihillalt, Oscar

    1997-01-01

    Operating experiences of Atucha-1 and Embalse Nuclear Power Plants were discussed in this work. The technical and economic aspects, such as reliability, availability, personnel training, operating costs, prices and market, which exercise influence upon Argentina nuclear energy policy, mainly on the power electric generation by nuclear power plants were considered. Finally the current status of the nucleoelectric sector in Argentina and forecasting were analysed

  19. Mechanisms of vegetation removal by floods on bars of a heavily managed gravel bed river (The Isere River, France)

    Jourdain, Camille; Belleudy, Philippe; Tal, Michal; Malavoi, Jean-René

    2016-04-01

    In natural alpine gravel bed rivers, floods and their associated bedload transport maintain channels active and free of mature woody vegetation. In managed rivers, where flood regime and sediment supply have been modified by hydroelectric infrastructures and sediment mining, river beds tend to stabilize. As a result, in the recent past, mature vegetation has established on gravel bars of many gravel bed rivers worldwide. This established vegetation increases the risk of flooding by decreasing flow velocity and increasing water levels. In addition, the associated reduction in availability of pioneer habitats characteristic of these environments typically degrades biodiversity. Managing hydrology in a way that would limit vegetation establishment on bars presents an interesting management option. In this context, our study aims at understanding the impacts of floods of varying magnitude on vegetation removal, and identifying and quantifying the underlying mechanisms. Our study site is the Isère River, a heavily managed gravel bed river flowing in the western part of the French Alps. We studied the impact of floods on sediment transport and vegetation survival at the bar scale through field monitoring from 2014 to 2015, focusing on young salicaceous vegetation (chains, and topographic surveys. Hourly water discharge was obtained from the national gauging network. The hydraulics of monitored floods was characterized using a combination of field measurements and 2D hydraulic modeling: water levels were measured with pressure sensors and Large Scale Particle Velocimetry was used to measure flow velocities. These data were used to calibrate 2D hydrodynamic model using TELEMAC2D. At the reach scale, removal of mature vegetation was assed using a series of historical aerial photographs between 2001 and 2015. Our monitoring period covered a series of floods with recurrence intervals of 2 to 4 times per year, as well as one large flood with a 10 year return period. Only the

  20. Can we enhance amphibians' habitat restoration in the post-mining areas?

    Klimaszewski, Krzysztof; Pacholik, Ewa; Snopek, Adam

    2016-09-01

    The study was aimed to evaluate the selected improvements of nature restoration in a depleted gravel pit. The study site consisted of four water reservoirs of different shapes and sizes, flooded after the gravel extraction ended. Ecological succession monitoring, conducted by the Warsaw University of Life Sciences students associated in the Student Scientific Association of Animal Sciences Faculty since the completion of mining, have focused on amphibians. A twofold approach upheld amphibian species population dynamics, as well as selected habitat elements. The restoration practices dedicated to habitat conditions enhancing have been proved to be definitely effective and useful for similar sites.

  1. Mine Water Treatment in Hongai Coal Mines

    Dang Phuong Thao; Dang Vu Chi

    2018-01-01

    Acid mine drainage (AMD) is recognized as one of the most serious environmental problem associated with mining industry. Acid water, also known as acid mine drainage forms when iron sulfide minerals found in the rock of coal seams are exposed to oxidizing conditions in coal mining. Until 2009, mine drainage in Hongai coal mines was not treated, leading to harmful effects on humans, animals and aquatic ecosystem. This report has examined acid mine drainage problem and techniques for acid mine ...

  2. Measurement of the bed material of gravel-bed rivers

    Milhous, R.T.; ,

    2002-01-01

    The measurement of the physical properties of a gravel-bed river is important in the calculation of sediment transport and physical habitat values for aquatic animals. These properties are not always easy to measure. One recent report on flushing of fines from the Klamath River did not contain information on one location because the grain size distribution of the armour could not be measured on a dry river bar. The grain size distribution could have been measured using a barrel sampler and converting the measurements to the same as would have been measured if a dry bar existed at the site. In another recent paper the porosity was calculated from an average value relation from the literature. The results of that paper may be sensitive to the actual value of porosity. Using the bulk density sampling technique based on a water displacement process presented in this paper the porosity could have been calculated from the measured bulk density. The principle topics of this paper are the measurement of the size distribution of the armour, and measurement of the porosity of the substrate. The 'standard' method of sampling of the armour is to do a Wolman-type count of the armour on a dry section of the river bed. When a dry bar does not exist the armour in an area of the wet streambed is to sample and the measurements transformed analytically to the same type of results that would have been obtained from the standard Wolman procedure. A comparison of the results for the San Miguel River in Colorado shows significant differences in the median size of the armour. The method use to determine the porosity is not 'high-tech' and there is a need improve knowledge of the porosity because of the importance of porosity in the aquatic ecosystem. The technique is to measure the in-situ volume of a substrate sample by measuring the volume of a frame over the substrate and then repeated the volume measurement after the sample is obtained from within the frame. The difference in the

  3. Extending mine life

    Anon.

    1984-01-01

    Mine layouts, new machines and techniques, research into problem areas of ground control and so on, are highlighted in this report on extending mine life. The main resources taken into account are coal mining, uranium mining, molybdenum and gold mining

  4. Uranium mining

    2008-01-01

    Full text: The economic and environmental sustainability of uranium mining has been analysed by Monash University researcher Dr Gavin Mudd in a paper that challenges the perception that uranium mining is an 'infinite quality source' that provides solutions to the world's demand for energy. Dr Mudd says information on the uranium industry touted by politicians and mining companies is not necessarily inaccurate, but it does not tell the whole story, being often just an average snapshot of the costs of uranium mining today without reflecting the escalating costs associated with the process in years to come. 'From a sustainability perspective, it is critical to evaluate accurately the true lifecycle costs of all forms of electricity production, especially with respect to greenhouse emissions, ' he says. 'For nuclear power, a significant proportion of greenhouse emissions are derived from the fuel supply, including uranium mining, milling, enrichment and fuel manufacture.' Dr Mudd found that financial and environmental costs escalate dramatically as the uranium ore is used. The deeper the mining process required to extract the ore, the higher the cost for mining companies, the greater the impact on the environment and the more resources needed to obtain the product. I t is clear that there is a strong sensitivity of energy and water consumption and greenhouse emissions to ore grade, and that ore grades are likely to continue to decline gradually in the medium to long term. These issues are critical to the current debate over nuclear power and greenhouse emissions, especially with respect to ascribing sustainability to such activities as uranium mining and milling. For example, mining at Roxby Downs is responsible for the emission of over one million tonnes of greenhouse gases per year and this could increase to four million tonnes if the mine is expanded.'

  5. Active mines in Arizona - 1993. Directory 40

    Phillips, K.A.; Niemuth, N.J.; Bain, D.R.

    1992-01-01

    A directory of the active mines in Arizona is presented. The directory was compiled in November, 1992 from field visits and information received by the Department's technical staff. For the purpose of this directory, an active mine is defined as a mine in continuous operation, either in production or under full-time development for production. Custom milling operations that are active or available on a full-time basis are also included in the directory. It is acknowledged that there are additional mines not listed that are in an exploration, evaluation, or part-time development phase. There are others where production is on an intermittent basis that are not listed. The report is dependent on the cooperation of government agencies, private industry, and individuals who voluntarily provide information on their projects and activities. The directory is arranged alphabetically by company name. Each listing includes corporate addresses, mine name and location, operation description, and key personnel. The listing for the sand and gravel operations include name, address, and phone number

  6. Mineralogical data on angelaite, Cu2AgPbBiS4, from the Los Manantiales District, Chubut, Argentina

    Topa, D.; Paar, W.H.; Putz, H.

    2010-01-01

    Angelaite, ideally Cu2AgPbBiS4, occurs as a hypogene mineral in polymetallic ores at the Ángela groups of veins in the mining district of Los Manantiales, in the province of Chubut, Argentina. The new mineral species is predominantly associated with pyrite, sphalerite, chalcopyrite, hematite...

  7. Incidence of social resistance in provincial mining legislation. The cases of Córdoba and Catamarca (2003-2008

    Lucas Christel

    2013-11-01

    Full Text Available During the last decade in Argentina, the growth of open pit mining has faced strong social resistance and provincial laws prohibiting such activity. This work aims to analyse the ways in which the different subnational political regimes and economic systems impact upon the possibility of incidence of social resistance on provincial mining legislation, looking at the cases of Cordoba and Catamarca.

  8. Ecosystem services provided by a former gravel extraction site in the uk under two contrasting restoration states

    Phillip J Blaen

    2016-01-01

    Full Text Available Mineral extraction sites restored for nature conservation can provide areas of high quality habitat and enhance local biodiversity, yet the ecosystem services and associated socio-economic benefits delivered by such sites are not well understood. Here we use a combination of primary field data, benefit transfer, and visitor questionnaires to assess ecosystem services provided by a former gravel mining site restored for nature conservation. We quantify the marginal benefits accrued from the site by comparing ecosystem service delivery from the current nature conservation state to delivery under a highly plausible alternative restoration state; namely a public amenity park. Our results suggest restoration for nature conservation is associated with relatively high carbon storage, but that carbon sequestration is offset to some degree by greenhouse gas fluxes from saturated reed bed areas. We demonstrate through a zonal travel-cost method and individual interviews that restoration for nature conservation contributes to local amenity value by providing specialised wildlife viewing opportunities to visitors. Our results highlight the potential ecosystem services associated with mineral sites restored for nature conservation. Notably, this study strengthens the evidence base to support the case for biodiversity-focused restoration of these extraction sites, both to the minerals industry and governmental planners, by suggesting that such restoration strategies may play an important role in contributing to human well-being without impeding economic progress.

  9. Effect of percentage of low plastic fines on the unsaturated shear strength of compacted gravel soil

    Kamal Mohamed Hafez Ismail Ibrahim

    2015-06-01

    Full Text Available Low plastic fines in gravel soils affect its unsaturated shear strength due to the contribution of matric suction that arises in micro and macro pores found within and between aggregates. The shear strength of five different types of prepared gravel soils is measured and is compared with a theoretical model (Fredlund et al., 1978 to predict the unsaturated shear strength. The results are consistent to a great extent except the case of dry clayey gravel soil. It is also found that on inundation of gravel soils containing plastic fines greater than 12% a considerable reduction in both the strength and the stiffness modulus is noticed. This 12% percentage is close to the accepted 15% percentage of fines given by ASTM D4318 (American society for testing material. The angle of internal friction that arises due to matric suction decreases with the increase of degree of saturation of soil. The hysteresis of some tested gravel soils is measured and found that it increases by increasing the percentage of fines.

  10. Gravel admix, vegetation, and soil water interactions in protective barriers: Experimental design, construction, and initial conditions

    Waugh, W.J.

    1989-05-01

    The purpose of this study is to measure the interactive effects of gravel admix and greater precipitation on soil water storage and plant abundance. The study is one of many tasks in the Protective Barrier Development Program for the disposal of Hanford defense waste. A factorial field-plot experiment was set up at the site selected as the borrow area for barrier topsoil. Gravel admix, vegetation, and enhanced precipitation treatments were randomly assigned to the plots using a split-split plot design structure. Changes in soil water storage and plant cover were monitored using neutron probe and point intercept methods, respectively. The first-year results suggest that water extraction by plants will offset gravel-caused increases in soil water storage. Near-surface soil water contents were much lower in graveled plots with plants than in nongraveled plots without plants. Large inherent variability in deep soil water storage masked any effects gravel may have had on water content below the root zone. In the future, this source of variation will be removed by differencing monthly data series and testing for changes in soil water storage. Tests of the effects of greater precipitation on soil water storage were inconclusive. A telling test will be possible in the spring of 1988, following the first wet season during which normal precipitation is doubled. 26 refs., 9 figs., 9 tabs

  11. Coccocypselum pulchellum (Rubiaceae, nuevo registro para Argentina

    Elsa L. Cabral

    2007-01-01

    Full Text Available Se cita Coccocypselum pulchellum por primera vez para Argentina, en Predio Guaraní, Misiones. Esta es la tercera especie de Coccocypselum registrada para la flora de Argentina junto con C. hasslerianum y C. lanceolatum. Se incluyen descripciones, ilustraciones y una clave para reconocer las tres especies argentinas de Coccocypselum.

  12. Argentina: Background and U.S. Relations

    2008-11-05

    Comercio Internacional, Y Culto, Comunicado de la Cancillería Argentina, September 11, 2008. 43 A. Rebossio, "Fernández Acusa al FBI de Desestablizar...Argentina," El País (Madrid), September 13, 2008. 44 “Argentina Slams Witness in Cash Suitcase Scandal,” Associated Press Newswires, November 4, 2008

  13. Climatology of hail in Argentina

    Mezher, Romina N.; Doyle, Moira; Barros, Vicente

    2012-10-01

    The annual cycle, annual and seasonal frequency and geographical distribution of hail in Argentina during the 1960-2008 period are examined. Eight regions covering the whole territory were defined based on the correlation of the mean annual hail frequency between all weather stations. Regions lying between 30° and 40°S as well as those dominated by mountains present the highest hail frequencies in Argentina. The eastern and coastal areas of the country experience hail events mainly during springtime but they may start in late winter and continue through the beginning of summer. Events in western and central Argentina also predominate in spring but the maximum frequencies are observed during summer months. Trends in the annual number of hail events calculated for each region indicate that events in northwestern and northeastern Argentina have been increasing as well as in southern Patagonia. On the other hand, in central Argentina, southern Buenos Aires-La Pampa, northern Buenos Aires-Litoral and northern Patagonia trends are negative and statistically significant in the first two regions, basically by the decrease of events during spring and summer.

  14. Nuclear Activities in Argentina, 2010

    Ferreri, J.C.; Ferreri, J.C.; Clausse, A.; Clausse, A.; Clausse, A.; Ordonez, J.P.; Mazzantini, O.A.

    2011-01-01

    Nuclear activities in Argentina are restarted. After almost two decades of near stagnation, the governments political decision of August 2006 regarding electrical energy production, considered the nuclear option as a valid one to solve the problems of the growing demand of electrical energy. This decision triggered again the activities related to the finalization of the third nuclear power reactor (Atucha-II), now actively progressing, the construction of a prototype of the CAREM integral advanced reactor, the life extension of the Embalse CANDU nuclear power plant (NPP) and the studies for the emplacement of a fourth NPP in an appropriate site. In all those years of near stagnation, there were notable exceptions related to the design and construction of experimental and radioisotope production reactors, led by INVAP, a state-owned industry, which exported its production. The accompanying industries of nuclear fuel elements production also remained active, given the demand of the two active NPPs. Meanwhile, the National Atomic Energy Commission of Argentina continued the efforts on research and development that were at the base of the technological achievements of the nuclear activities in Argentina. Nuclear safety studies associated with Atucha II and Embalse NPPs and radiological safety were also a substantive part of the continued efforts by Nucleo-Electrica de Argentina SA and the Nuclear Regulatory Authority of Argentina

  15. Danger on mountain roads, Iglesia Department, San Juan, Argentina

    Varela, S.; Puertas, M.

    2007-01-01

    This paper is related to Mining Projects at Valle del Cura - Iglesia Department-San Juan Province-Argentina Republic. Basis for an Integrated Management of a Sustainable Mining.It aims at locating and analyzing natural dangers which may interfere high mountain paths, such as climatic, anthropic and/or tectonic factors since they may stop a region development. A hillside, a mountainside,a talus or a slope may have, due to their extensive areas, either lithological or structural variations which might determine the presence of un stability phenomena.The cordillera n Iglesia sector major dangers are related to mass displacement movements as a result of the great quantity of unstable detritus situated in valleys slopes.Landsat images, aerial photographs, topographic and geological maps data allowed to detect several sectors that may generate mass displacement movements, Arroyo de Aguas Negras rising sector was selected because it is on the right of National Route No. 150 trace. It is not only a national, but also an international route that connects Argentina and Chile.(author)

  16. Country watch. Argentina.

    Perez, P

    1994-01-01

    The Argentine Network of Women Living with HIV/AIDS (ANW) provides general information about acquired immunodeficiency syndrome (AIDS), assistance in assessing medications through state and private services, and information concerning and referrals to nongovernmental organizations (NGOs) and governmental social services to low income women who have been diagnosed with human immunodeficiency virus (HIV) infection. Workshops allow the women to become more active on their own behalf and contribute to the reorientation of health and social services to better meet their needs. Due to the stigma attached to AIDS in Argentina, ANW works to ensure the human rights of these women through participation in the Ministry of Interior Programme against Discrimination and in public events that inform the community about the concerns of HIV positive women with regard to discrimination. A bulletin provides scientific and medical information, news on activities, model advocacy and policy statements, and addresses of support agencies. Contributions are accepted from all HIV positive women. In order to reach isolated cases outside of the capital, links are maintained with other AIDS organizations in the nation.

  17. Argentina and Brazil

    Gamba-Stonehouse, V.

    1991-01-01

    This paper reports that security is defined in different ways by many international actors. To some, security is tied to the definition of an external threat to borders, as in the case of the NATO countries. To other, security is related to development, as in the case of most Third World countries. but notwithstanding different definitions, all countries recognize that the essence of security is the survival of the nation-state itself. The nuclear programs of Argentina and Brazil are among the oldest, most sophisticated and advanced nuclear programs anywhere in the Third World. The programs have never been explained on the basis of threat perception, and in this regard perhaps they constitute the most atypical form of nuclear proliferation known to date. Not surprisingly, any attempt to explain the rationale for the Brazilian and Argentine nuclear programs based on common issues of threat =merely confuses the issue. Thus, nationalism, the search for national identity and pride, the need to express self-sufficiency and the desire to keep options open in an insecure and evolving world order must all be analyzed to comprehend the likelihood of future types of nuclear proliferation. Meanwhile, the study of the contemporary era of Argentine-Brazilian nuclear rapprochement may provide new insights into the complex reasoning behind the decision of countries to go nuclear

  18. Pampa Húmeda, Argentina

    Néstor C. Di Leo

    2007-01-01

    Full Text Available La radiación fotosintéticamente activa (PAR es importante como variable de entrada de energía en diversos procesos biológicos y su evaluación temporal tiene particular interés en el monitoreo de cultivos. Los datos de reflectancia espectral, obtenidos mediante sensores remotos, son adecuados para proporcionar observaciones de fenómenos que se relacionan con aspectos ecofisiológicos de las cubiertas vegetales, incluyendo a la productividad primaria neta (NPP. Ésta constituye una de las pocas fuentes de información acerca de los procesos del ciclo del carbono en escalas regionales o globales. La NPP se relaciona con la eficiencia del uso de la luz a través de la radiación fotosintéticamente activa absorbida (APAR y representa un indicador agroecológico de utilidad para valorar la utilización productiva del territorio. El objetivo de este trabajo es presentar un aporte metodológico a la agroecología, mediante las caracterizaciones de la NPP y la APAR, en tres situaciones geográficas y productivas de la Pampa Húmeda, Argentina.

  19. Development of practical decontamination process for the removal of uranium from gravel.

    Kim, Ilgook; Kim, Gye-Nam; Kim, Seung-Soo; Choi, Jong-Won

    2018-01-01

    In this study, a practical decontamination process was developed to remove uranium from gravel using a soil washing method. The effects of critical parameters including particle size, H 2 SO 4 concentration, temperature, and reaction time on uranium removal were evaluated. The optimal condition for two-stage washing of gravel was found to be particle size of 1-2 mm, 1.0 M H 2 SO 4 , temperature of 60°C, and reaction time of 3 h, which satisfied the required uranium concentration for self-disposal. Furthermore, most of the extracted uranium was removed from the waste solution by precipitation, implying that the treated solution can be reused as washing solution. These results clearly demonstrated that our proposed process can be indeed a practical technique to decontaminate uranium-polluted gravel.

  20. Social big data mining

    Ishikawa, Hiroshi

    2015-01-01

    Social Media. Big Data and Social Data. Hypotheses in the Era of Big Data. Social Big Data Applications. Basic Concepts in Data Mining. Association Rule Mining. Clustering. Classification. Prediction. Web Structure Mining. Web Content Mining. Web Access Log Mining, Information Extraction and Deep Web Mining. Media Mining. Scalability and Outlier Detection.

  1. Thermal remediation of tar-contaminated soil and oil-contaminated gravel

    Anthony, E.J.; Wang, J.

    2005-01-01

    High temperature treatments are commonly considered for the decontamination of soil as they have the advantages of reliability, high capacity, and effective destruction of hazardous materials with reduced long-term liability. This paper examined the remediation of soil contaminated by coal tar as well as gravel contaminated by oil. Pilot plant studies were conducted using 2 representative incineration technologies: rotary kiln and fluidized bed. The coal tar contaminated soil had accumulated over a few decades at a calcination plant in western Canada. The soil was sticky and could not be handled by conventional feeding and combustion systems. Crushed lignite was mixed with the soil as an auxiliary fuel and to reduce stickiness. A pilot plant furnace was used to evaluate the potential of decontamination in a rotary calciner. An analysis of both a modelling study and the test results showed that complete decontamination could be achieved in the targeted calciner. The results suggested that energy recovery was also possible, which could in turn make the remediation process more cost-effective. Decontamination of oil-contaminated gravel was conducted with a pilot plant fluidized bed combustor to study the feasibility of using incineration technology in the remediation of gravel and debris contaminated by oil spills. Results indicated that the gravel was decontaminated with acceptable emission performance. It was concluded that the study will be valuable to the application of commercial incineration processes for the remediation of polluted soils. It was observed that the weathering of the oiled gravel lowered the rate of decontamination. A small amount of salt water resulted in lowered decontamination rates, which may be an important factor for situations involving the remediation of shoreline gravel contaminated by oil. 24 refs., 6 tabs., 7 figs

  2. Horizontal single-trip gravel pack and selective simulation system for deep water extended reach wells

    Pineda, Francisco [BJ Services Company, Houston, TX (United States); Vilela, Alvaro; Montanha, Roberto; Acosta, Marco; Farias, Rodrigo [BJ Services do Brasil Ltda., Rio de Janeiro, RJ (Brazil)

    2004-07-01

    Most of the reservoirs located in the deep water and ultra-deep water offshore South America are described as unconsolidated sandstone that require sand control on both producers and water injection wells. Horizontal Open Hole Gravel Pack completions are the preferred method of development. If completing heavy oil reservoirs, there is a necessity of longer horizontal open hole sections. Low fracture gradients may limit the length of gravel pack in the open hole section because of the pressure increase during the Beta wave proppant deposition phase. This system allows the gravel pack assembly to be installed and the gravel pack to be pumped during the alpha and beta wave deposition phases without the limitation of high pressures that could fracture the well. The benefits of the Horizontal Single-Trip Gravel Pack and Selective Stimulation System (HSTSSS) using the differential valve include the ability to complete longer horizontal intervals, valuable rig-time savings and, efficient mechanical diversion of the stimulation fluid. This paper outlines the application of the HSTSSS system using a differential valve to complete a horizontal well in offshore deep waters. The need for a differential valve is primarily in horizontal gravel packing operations when normal circulating rates and pressures around the open hole would exceed formation break down pressure. The valve is intended to be easily spaced out and run in the wash pipe. At a predetermined differential pressure the valve opens and the return flow path distance around the bottom of the tailpipe is shortened, thus reducing back pressure preventing filter cake damage without slowing the pump rate. In addition the said valve has to close to allow the selective stimulation to take place. Economic considerations along with completion efficiencies are especially important on deep water, subsea completions. The utilization of differential valves allows completion of extended-reach open hole wells and/or low fracture

  3. Crisis de la prensa Argentina

    Federico Rey Lennon

    2015-01-01

    Full Text Available La magnitud de la crisis económica Argentina es enorme y difícil saber hasta cuando se extenderá, agravada por una situación política frágil. La actual recesión ha hecho caer la inversión publicitaria a los niveles más bajos de los últimos años. De 1997 al 2001 la circulación de la prensa Argentina cayó en el 36 por ciento. El riesgo en Argentina es la eventual extranjerización de casi todos los medios de comunicación.

  4. STRUCTURE, GROWTH AND MORPHOLOGY OF FISH POPULATIONS FROM GRAVEL-PIT VUKOVINA

    Ivan Jakovlić

    2001-12-01

    Full Text Available After the structure of fish populations from gravel-pit Vukovina was determined, those populations were checked for 10 morphometric and 4 meristic parameters, as well as for length-mass relationship. For chub (Leuciscus cephalus and pumpkinseed (Lepomis gibbosus some meristic characters expressed the values beyond those mentioned in the standard key for the freshwater fish species determination. When compared to other locations, length-mass relationship and condition factor (CF were significantly lower for all checked populations. This indicates that gravel-pit Vukovina is extremely oligotrophic and has very poor fish production.

  5. A Visual Basic program to classify sediments based on gravel-sand-silt-clay ratios

    Poppe, L.J.; Eliason, A.H.; Hastings, M.E.

    2003-01-01

    Nomenclature describing size distributions is important to geologists because grain size is the most basic attribute of sediments. Traditionally, geologists have divided sediments into four size fractions that include gravel, sand, silt, and clay, and classified these sediments based on ratios of the various proportions of the fractions. Definitions of these fractions have long been standardized to the grade scale described by Wentworth (1922), and two main classification schemes have been adopted to describe the approximate relationship between the size fractions.Specifically, according to the Wentworth grade scale gravel-sized particles have a nominal diameter of ⩾2.0 mm; sand-sized particles have nominal diameters from <2.0 mm to ⩾62.5 μm; silt-sized particles have nominal diameters from <62.5 to ⩾4.0 μm; and clay is <4.0 μm. As for sediment classification, most sedimentologists use one of the systems described either by Shepard (1954) or Folk (1954, 1974). The original scheme devised by Shepard (1954) utilized a single ternary diagram with sand, silt, and clay in the corners to graphically show the relative proportions among these three grades within a sample. This scheme, however, does not allow for sediments with significant amounts of gravel. Therefore, Shepard's classification scheme (Fig. 1) was subsequently modified by the addition of a second ternary diagram to account for the gravel fraction (Schlee, 1973). The system devised by Folk (1954, 1974) is also based on two triangular diagrams (Fig. 2), but it has 23 major categories, and uses the term mud (defined as silt plus clay). The patterns within the triangles of both systems differ, as does the emphasis placed on gravel. For example, in the system described by Shepard, gravelly sediments have more than 10% gravel; in Folk's system, slightly gravelly sediments have as little as 0.01% gravel. Folk's classification scheme stresses gravel because its concentration is a function of

  6. Labour-based bitumen roads as cost-effective alternatives to conventional gravel wearing courses

    Paige-Green, P

    2004-09-01

    Full Text Available and streets. The potential for large-scale application of labour-based road works is therefore enormous. Delivery of a quality product is seen as key to the acceptance of labour-based road works. In Gundo Lashu it was realised early on that finding good... quality wearing course gravel in itself constituted a major problem in many areas of the province, thus bringing the costs for a fully rehabilitated and gravelled 5.5m wide road to about R230 000 in some instances. Aside from depleting an increasingly...

  7. Effects of Surface and Subsurface Bed Material Composition on Gravel Transport and Flow Competence Relations—Possibilities for Prediction

    Bunte, K.; Abt, S. R.; Swingle, K. W.; Cenderelli, D. A.; Gaeuman, D. A.

    2014-12-01

    Bedload transport and flow competence relations are difficult to predict in coarse-bedded steep streams where widely differing sediment supply, bed stability, and complex flow hydraulics greatly affect amounts and sizes of transported gravel particles. This study explains how properties of bed material surface and subsurface size distributions are directly related to gravel transport and may be used for prediction of gravel transport and flow competence relations. Gravel transport, flow competence, and bed material size were measured in step-pool and plane-bed streams. Power functions were fitted to gravel transport QB=aQb and flow competence Dmax=cQd relations; Q is water discharge. Frequency distributions of surface FDsurf and subsurface FDsub bed material were likewise described by power functions FDsurf=hD j and FDsub=kDm fitted over six 0.5-phi size classes within 4 to 22.4 mm. Those gravel sizes are typically mobile even in moderate floods. Study results show that steeper subsurface bed material size distributions lead to steeper gravel transport and flow competence relations, whereas larger amounts of sediment contained in those 6 size bedmaterial classes (larger h and k) flatten the relations. Similarly, steeper surface size distributions decrease the coefficients of the gravel transport and flow competence relations, whereas larger amounts of sediment within the six bed material classes increase the intercepts of gravel transport and flow competence relations. Those relations are likely causative in streams where bedload stems almost entirely from the channel bed as opposed to direct (unworked) contributions from hillslopes and tributaries. The exponent of the subsurface bed material distribution m predicted the gravel transport exponent b with r2 near 0.7 and flow competence exponent d with r2 near 0.5. The intercept of bed surface distributions h increased the intercept a of gravel transport and c of the flow competence relations with r2 near 0.6.

  8. Mine Water Treatment in Hongai Coal Mines

    Dang, Phuong Thao; Dang, Vu Chi

    2018-03-01

    Acid mine drainage (AMD) is recognized as one of the most serious environmental problem associated with mining industry. Acid water, also known as acid mine drainage forms when iron sulfide minerals found in the rock of coal seams are exposed to oxidizing conditions in coal mining. Until 2009, mine drainage in Hongai coal mines was not treated, leading to harmful effects on humans, animals and aquatic ecosystem. This report has examined acid mine drainage problem and techniques for acid mine drainage treatment in Hongai coal mines. In addition, selection and criteria for the design of the treatment systems have been presented.

  9. Mine Water Treatment in Hongai Coal Mines

    Dang Phuong Thao

    2018-01-01

    Full Text Available Acid mine drainage (AMD is recognized as one of the most serious environmental problem associated with mining industry. Acid water, also known as acid mine drainage forms when iron sulfide minerals found in the rock of coal seams are exposed to oxidizing conditions in coal mining. Until 2009, mine drainage in Hongai coal mines was not treated, leading to harmful effects on humans, animals and aquatic ecosystem. This report has examined acid mine drainage problem and techniques for acid mine drainage treatment in Hongai coal mines. In addition, selection and criteria for the design of the treatment systems have been presented.

  10. Clorities as geothermometer. La Bragada mine. Cordoba, Argentina

    Gonzalez, M.; Mas, G.

    1998-01-01

    Clorities have been proposed as geothermometer in geothermal and hydrothermal environments environments because they show a rather wide range of variation in their structural and chemical characteristics, regarded with the temperature of formation. Taking into account that this group of minerals constitute one of the main products of the hydrothermal alteration of the host rocks at the mesothermal gold deposit La Bragada. The optical and XRD study of these minerals have been performed in order to used them as geothermometer . The relation of this geothermometer with fluid inclusions thermometry in the same deposit has been analyzed in order to assess their use as a quick and simple mean for the thermometric characterization of an alteration zone. (author)

  11. Sovereignties in Conflict: Socio-environmental Mobilization and the Glaciers Law in Argentina

    Lucas Christel; Daniel Torunczyk

    2017-01-01

    Until 2010, the cycle of socio-environmental mobilization in Argentina against transnational mining that began in 2003 had influenced legislative power only at subnational levels. The enactment of the Glaciers Law in 2010 constituted the first time that socio-environmental mobilization successfully influenced legislative power at the federal level. This article makes a double contribution to the analysis of this type of conflict. In theoretical terms, through the notion of “sovereignties in c...

  12. Fly ash stabilisation of gravel roads; Flygaska som foerstaerkningslager i grusvaeg

    Macsik, Josef

    2006-01-15

    Majority of the existing gravel roads have low bearing capacity during spring and autumn, due to thaw and/or rain. Low bearing capacity leads often to bad road conditions. This situation results in higher costs for the lumber industry and the public. Management of gravel roads all the year around would traditionally require excavation of frost susceptible soils and replacement with natural materials. Fly ash (from bio fuels) has good technical properties as bearing layer in road constructions. Fly ash stabilised gravel roads have better function and longer life span with less maintenance than traditional gravel roads. The aim of this project is to show how fly ash stabilisation of gravel roads can increase bearing capacity and what its environmental impact is. The overall aim is to make it easier for entrepreneurs and consulting companies to use fly ash during gravel road renovation and/or constructing new gravel roads. This report targets fly ash producers and road constructors as well as environmental agencies. Two different pilot tests were investigated in this study, Norberg with fly ash from Stora Enso Fors AB, and Boerje (Uppsala) with fly ash from Vattenfall Uppsala AB. Both road sections with related reference section were investigated during a two year period. Only fly ash was used in the bearing layer at Norberg and fly ash gravel was used at Boerje. Bearing capacity was investigated twice, for both locations, November 2003 one month after the road renovation and during thawing, April 2004. Water samples from lysimeters, ground water and surface water were only collected and analysed from Norberg. Experience from the fly ash stabilised road sections show that curing and traffic load can with time compensate for less compaction. The same is noticed at Boerje, although deflection measurements show that there are small differences. Stabilisation of gravel roads increases the roads bearing capacity. Two years after stabilisation 90 timber loads were

  13. Environmentalism(s and natural assets: challenges to extractivism in Argentina and Brazil

    Lucrecia Wagner

    2013-11-01

    Full Text Available This paper tackles environmental conflicts generated for struggles for land and water, facing the advance of the extractive frontier -principally, monocultures and mega mining- from the action of social movements in Brazil and Argentina.Considering the currents of environmentalism which get into a dispute over the appropriation of natural commons, we will argue how social movements in Brazil and Argentina demonstrate the fallacy of the hegemonic capitalist discourse about the environmental crisis. Thus, we will consider emblematic movements in each country: the Movement of “Trabajadores Rurales Sin Tierra (MST” of Brazil and the movements that resist the large-scale mining -or mega-mining-in Argentina. The characterization of these movements is grounded in researches that included interviews and field work in these territories of resistance.We believe that these conflicts and their social actors bring to light the inequalities inherent to the distribution of environmental impacts, which the rhetoric of sustainable development attempts to hide with its socially inclusive and environmentally friendly conception.Environmental conflicts provide the possibility of quashing the hegemonic image of an environmental crisis common to all and simultaneously, installing the discussion about the legitimate need of the appropriation of natural commons.

  14. Distribution and stability of potential salmonid spawning gravels in steep boulder-bed streams of the eastern Sierra Nevada

    Kondolf, G.M.; Cada, G.F.; Sale, M.J.; Felando, T.

    1991-01-01

    Interest in small hydroelectric development (< 5 MW) has recently focused attention on steep streams and the resident trout populations they contain. High-gradient boulder-bed streams have been the sites of relatively few studies of salmonid spawning habitat, although they have geomorphic and hydraulic characteristics - and therefore gravel distributions - that are quite different from the more commonly described lower-gradient channels. The authors documented gravel distribution in seven high-gradient stream reaches in the eastern Sierra Nevada. Gravels occurred only in locations characterized by relatively low shear stress; they formed small pockets in sites of low divergence and larger deposits upstream of natural hydraulic controls. In 1986 (a wet year), all tracer gravels placed in gravel pockets at nine sites on four streams were completely swept away, and substantial scour, fill, and other channel changes occurred at many sites. In 1987 (a dry year), tracer gravels and the channel cross sections were generally stable. Periodic mobility of gravel may explain why brown trout Salmo trutta are more abundant than rainbow trout Oncorhychus mykiss in the study reaches, where high flows occur every May and June during snowmelt. Brown trout are fall spawners, and their fry emerge long before the high snowmelt flows, whereas rainbow trout are spring spawners whose eggs are in the gravel, and thus vulnerable to scour, during snowmelt flows

  15. Resistivity profiling for mapping gravel layers that may control contaminant migration at the Amargosa Desert Research Site, Nevada

    Lucius, Jeffrey E.; Abraham, Jared D.; Burton, Bethany L.

    2008-01-01

    Gaseous contaminants, including CFC 113, chloroform, and tritiated compounds, move preferentially in unsaturated subsurface gravel layers away from disposal trenches at a closed low-level radioactive waste-disposal facility in the Amargosa Desert about 17 kilometers south of Beatty, Nevada. Two distinct gravel layers are involved in contaminant transport: a thin, shallow layer between about 0.5 and 2.2 meters below the surface and a layer of variable thickness between about 15 and 30 meters below land surface. From 2003 to 2005, the U.S. Geological Survey used multielectrode DC and AC resistivity surveys to map these gravel layers. Previous core sampling indicates the fine-grained sediments generally have higher water content than the gravel layers or the sediments near the surface. The relatively higher electrical resistivity of the dry gravel layers, compared to that of the surrounding finer sediments, makes the gravel readily mappable using electrical resistivity profiling. The upper gravel layer is not easily distinguished from the very dry, fine-grained deposits at the surface. Two-dimensional resistivity models, however, clearly identify the resistive lower gravel layer, which is continuous near the facility except to the southeast. Multielectrode resistivity surveys provide a practical noninvasive method to image hydrogeologic features in the arid environment of the Amargosa Desert.

  16. A laboratory experiment on the evolution of a sand gravel reach under a lack of sediment supply

    Orru, C.; Chavarrias Borras, V.; Ferrara, V.; Stecca, G.; Blom, A.

    2015-01-01

    A flume experiment was conducted to examine the evolution of a sand-gravel reach under a lack of sediment supply. A bed composed of a bimodal sediment mixture was installed with a uniform slope and an gradual fining pattern. At the upstream end of the flume the initial bed consisted of 100% gravel,

  17. 32 CFR 644.551 - Equal opportunity-sales of timber, embedded sand, gravel, stone, and surplus structures.

    2010-07-01

    ... § 644.551 Equal opportunity—sales of timber, embedded sand, gravel, stone, and surplus structures... 32 National Defense 4 2010-07-01 2010-07-01 true Equal opportunity-sales of timber, embedded sand, gravel, stone, and surplus structures. 644.551 Section 644.551 National Defense Department of Defense...

  18. Response of bed mobility to sediment supply in natural gravel bed channels: A detailed examination and evaluation of mobility parameters

    T. E. Lisle; J. M. Nelson; B. L. Barkett; J. Pitlick; M. A. Madej

    1998-01-01

    Recent laboratory experiments have shown that bed mobility in gravel bed channels responds to changes in sediment supply, but detailed examinations of this adjustment in natural channels have been lacking, and practical methodologies to measure bed mobility have not been tested. We examined six gravel-bed, alternate-bar channels which have a wide range in annual...

  19. Coastal mining

    Bell, Peter M.

    The Exclusive Economic Zone (EEZ) declared by President Reagan in March 1983 has met with a mixed response from those who would benefit from a guaranteed, 200-nautical-mile (370-km) protected underwater mining zone off the coasts of the United States and its possessions. On the one hand, the U.S. Department of the Interior is looking ahead and has been very successful in safeguarding important natural resources that will be needed in the coming decades. On the other hand, the mining industry is faced with a depressed metals and mining market.A report of the Exclusive Economic Zone Symposium held in November 1983 by the U.S. Geological Survey, the Mineral Management Service, and the Bureau of Mines described the mixed response as: “ … The Department of Interior … raring to go into promotion of deep-seal mining but industrial consortia being very pessimistic about the program, at least for the next 30 or so years.” (Chemical & Engineering News, February 5, 1983).

  20. Surface Mines, Other - Longwall Mining Panels

    NSGIC Education | GIS Inventory — Coal mining has occurred in Pennsylvania for over a century. A method of coal mining known as Longwall Mining has become more prevalent in recent decades. Longwall...

  1. Response of Vegetation on Gravel Bars to Management Measures and Floods: Case Study From the Czech Republic

    Eremiášová Renata

    2014-08-01

    Full Text Available This article investigates response of vegetation on gravel bars to management measures and floods. The management measures consisted of the partial removal of gravel and vegetation cover, and were applied to six gravel bars on the Ostravice River, Czech Republic. Unexpected floods occu-rred in 2010, with the amplitude of 5- to 50-year repetition. Research of vegetation on the gravel bars consisted of vegetation survey before the management works; the monitoring of vegetation development over the following year and the verification of the relationships of species diversity, successional stages and the biotope conditions with the help of multivariate analysis (detrended correspondence analysis. Vegetation on the gravel bars was at different successional stages, and had higher diversity and vegetation cover before the management measures and floods. The mul-tivariate analysis revealed a shift toward initial successional stages with high demand on moisture, temperature and light after both management measures and floods.

  2. NREL technical assistance to Argentina

    Lilienthal, P. [National Renewable Energy Lab., Golden, CO (United States)

    1997-12-01

    This paper describes assistance to Argentina from the National Renewable Energy Laboratory which has touched on four programs: tariff analysis for rural concessions programs; wind/diesel hybrid retrofits in Patagonia; small hybrid systems designs for rural schools; an assessment of wind resources. The paper expands briefly on the first two points.

  3. Frost susceptibility of sub-base gravel used in Pearl-Chain Bridges: an experimental investigation

    Lund, Mia Schou Møller; Hansen, Kurt Kielsgaard; Andersen, Iben Brøndum

    2016-01-01

    This study investigates frost susceptibility of sub-base gravel determined by the ASTM D5918-13 standard as a conservative estimate of the frost heave risk of fill in overfilled arch bridges, particularly in Pearl-Chain Bridges. Frost heave of granular materials has been of great research interes...

  4. Image analysis to measure sorting and stratification applied to sand-gravel experiments

    Orrú, C.

    2016-01-01

    The main objective of this project is to develop new measuring techniques for providing detailed data on sediment sorting suitable for sand-gravel laboratory experiments. Such data will be of aid in obtaining new insights on sorting mechanisms and improving prediction capabilities of morphodynamic

  5. Sediment transport primer: estimating bed-material transport in gravel-bed rivers

    Peter Wilcock; John Pitlick; Yantao Cui

    2009-01-01

    This primer accompanies the release of BAGS, software developed to calculate sediment transport rate in gravel-bed rivers. BAGS and other programs facilitate calculation and can reduce some errors, but cannot ensure that calculations are accurate or relevant. This primer was written to help the software user define relevant and tractable problems, select appropriate...

  6. GRAIN-SIZE MEASUREMENTS OF FLUVIAL GRAVEL BARS USING OBJECT-BASED IMAGE ANALYSIS

    Pedro Castro

    2018-01-01

    Full Text Available Traditional techniques for classifying the average grain size in gravel bars require manual measurements of each grain diameter. Aiming productivity, more efficient methods have been developed by applying remote sensing techniques and digital image processing. This research proposes an Object-Based Image Analysis methodology to classify gravel bars in fluvial channels. First, the study evaluates the performance of multiresolution segmentation algorithm (available at the software eCognition Developer in performing shape recognition. The linear regression model was applied to assess the correlation between the gravels’ reference delineation and the gravels recognized by the segmentation algorithm. Furthermore, the supervised classification was validated by comparing the results with field data using the t-statistic test and the kappa index. Afterwards, the grain size distribution in gravel bars along the upper Bananeiras River, Brazil was mapped. The multiresolution segmentation results did not prove to be consistent with all the samples. Nonetheless, the P01 sample showed an R2 =0.82 for the diameter estimation and R2=0.45 the recognition of the eliptical ft. The t-statistic showed no significant difference in the efficiencies of the grain size classifications by the field survey data and the Object-based supervised classification (t = 2.133 for a significance level of 0.05. However, the kappa index was 0.54. The analysis of the both segmentation and classification results did not prove to be replicable.

  7. Coupling fine particle and bedload transport in gravel-bedded streams

    Park, Jungsu; Hunt, James R.

    2017-09-01

    Fine particles in the silt- and clay-size range are important determinants of surface water quality. Since fine particle loading rates are not unique functions of stream discharge this limits the utility of the available models for water quality assessment. Data from 38 minimally developed watersheds within the United States Geological Survey stream gauging network in California, USA reveal three lines of evidence that fine particle release is coupled with bedload transport. First, there is a transition in fine particle loading rate as a function of discharge for gravel-bedded sediments that does not appear when the sediment bed is composed of sand, cobbles, boulders, or bedrock. Second, the discharge at the transition in the loading rate is correlated with the initiation of gravel mobilization. Third, high frequency particle concentration and discharge data are dominated by clockwise hysteresis where rising limb discharges generally have higher concentrations than falling limb discharges. These three observations across multiple watersheds lead to a conceptual model that fine particles accumulate within the sediment bed at discharges less than the transition and then the gravel bed fluidizes with fine particle release at discharges above the transition discharge. While these observations were individually recognized in the literature, this analysis provides a consistent conceptual model based on the coupling of fine particle dynamics with filtration at low discharges and gravel bed fluidization at higher discharges.

  8. The effect of coarse gravel on cohesive sediment entrapment in an annular flume

    K. Glasbergen

    2015-03-01

    Full Text Available While cohesive sediment generally represents a small fraction (16 Pa, cohesive materials trapped within the gravel bed will be entrained and transported into the Glenmore Reservoir, where sediment-associated nutrients may pose treatment challenges to the drinking water supply.

  9. The relationship between emergence from spawning gravel and growth in farmed rainbow trout Oncorhynchus mykiss

    Åberg Andersson, Madelene; Laursen, Danielle Caroline; SILVA, P.I.M.

    2013-01-01

    The relationship between the timing of emergence from spawning gravel and growth after emergence was investigated in farmed Oncorhynchus mykiss. A relationship between the time of emergence and growth became evident after 6 months of rearing, where individuals with an intermediate emergence time...

  10. Process mining

    van der Aalst, W.M.P.; Rubin, V.; Verbeek, H.M.W.

    2010-01-01

    Process mining includes the automated discovery of processes from event logs. Based on observed events (e.g., activities being executed or messages being exchanged) a process model is constructed. One of the essential problems in process mining is that one cannot assume to have seen all possible...... behavior. At best, one has seen a representative subset. Therefore, classical synthesis techniques are not suitable as they aim at finding a model that is able to exactly reproduce the log. Existing process mining techniques try to avoid such “overfitting” by generalizing the model to allow for more...... support for it). None of the existing techniques enables the user to control the balance between “overfitting” and “underfitting”. To address this, we propose a two-step approach. First, using a configurable approach, a transition system is constructed. Then, using the “theory of regions”, the model...

  11. Effects of Gravel Bars on Nutrient Spiraling in Bedrock-Alluvium Streams

    Iobst, B. R.; Carroll, E. P.; Furbish, D. J.

    2007-05-01

    The importance of the connection between nutrient transport and local stream geomorphology is becoming increasingly important. Studies have shown that the interconnectivity of nutrient cycles in the downstream direction is in part controlled by the distribution and size of gravel bars in low order streams, as hyporheic flow occurs dominantly through alternate and mid-channel gravel bars. For this investigation multiple gravel bars in a 3rd order bedrock-alluvium stream were studied to determine general relationships between nutrient spiraling and hyporheic flow. The first goal was to understand (1) the extent to which water moves through hyporheic zones and (2) the basic chemistry of the hyporheic water. The second part of the study was to understand how nutrients, notably nitrogen, are affected in their cycling by the relatively long residence times encountered in gravel bars during hyporheic flow. Wells were installed along a 600 m reach of Panther Creek, KY in selected bars, as well as in a secondary location involving a grid installation pattern in one large bar. Results have shown that hyporheic flow through gravel bars is an important factor in influencing stream chemistry. Background water chemistry surveys have shown that certain parameters, specifically ammonium and nitrogen concentrations vary downstream, and that the dominant control over these changes is gravel bar location. Rhodamine WT was used in field tracer tests to track the travel times of water through bars as well as partitioning of water between the open channel and hyporheic flows. Further tests will be conducted utilizing a stable isotope study to determine how nitrogen is affected by hyporheic flow, and what implications this has for nutrient transport. We expect results to show that the spacing and size of gravel bars is a dominant control in key nutrient spiraling parameters, namely uptake lengths and overall nitrogen cycling rates. This has implications for how natural systems will

  12. Ecological significance of riverine gravel bars in regulated river reaches below dams

    Ock, G.; Takemon, Y.; Sumi, T.; Kondolf, G. M.

    2012-12-01

    A gravel bar has been recognized as ecologically significant in that they provide simplified habitat with topographical, hydrological and thermo-chemical diversity, while enhancing material exchanges as interfaces laterally between aquatic and terrestrial habitats, and vertically between surface and subsurface waters. During past several decades, regulated rivers below dams have been loss of a number of the geomorphological features due to sediment starvation by upstream dams, accompanied by a subsequent degradation of their ecological functions. Despite a growing concern for gravel bar management recognizing its importance in recovering riverine ecosystem services, the ecological roles of gravel bars have not been assessed enough from the empirical perspectives of habitat diversity and organic matter interactions. In this study, we investigate the 'natural filtering effects' for reducing lentic plankton and contaminants associated with self-purification, and 'physicochemical habitat complexity' of gravel bars, focusing on reach-scaled gravel bars in rivers located in three different countries; First is the Uji River in central Japan, where there has been a loss of gravel bars in the downstream reaches since an upstream dam was constructed in 1965; second is the Tagliamento River in northeast Italy, which shows morphologically intact braided bar channels by natural flooding events and sediment supply; third is the Trinity River in the United States (located in northern California), the site of ongoing restoration efforts for creating new gravel bars through gravel augmentation and channel rehabilitation activities. We traced the downstream changes in particulate organic matter (POM) trophic sources (composed of allochthonous terrestrial inputs, autochthonous instream production and lentic plankton from dam outflows) in order to evaluate the roles of the geomorphological features in tailwater ecosystem food-resources shifting. We calculated suspended POM

  13. Estimated sand and gravel resources of the South Merrimack, Hillsborough County, New Hampshire, 7.5-minute quadrangle

    Sutphin, D.M.; Drew, L.J.; Fowler, B.K.

    2006-01-01

    A computer methodology is presented that allows natural aggregate producers, local governmental, and nongovernmental planners to define specific locations that may have sand and gravel deposits meeting user-specified minimum size, thickness, and geographic and geologic criteria, in areas where the surficial geology has been mapped. As an example, the surficial geologic map of the South Merrimack quadrangle was digitized and several digital geographic information system databases were downloaded from the internet and used to estimate the sand and gravel resources in the quadrangle. More than 41 percent of the South Merrimack quadrangle has been mapped as having sand and (or) gravel deposited by glacial meltwaters. These glaciofluvial areas are estimated to contain a total of 10 million m3 of material mapped as gravel, 60 million m3 of material mapped as mixed sand and gravel, and another 50 million m3 of material mapped as sand with minor silt. The mean thickness of these areas is about 1.95 meters. Twenty tracts were selected, each having individual areas of more than about 14 acres4 (5.67 hectares) of stratified glacial-meltwater sand and gravel deposits, at least 10-feet (3.0 m) of material above the watertable, and not sterilized by the proximity of buildings, roads, streams and other bodies of water, or railroads. The 20 tracts are estimated to contain between about 4 and 10 million short tons (st) of gravel and 20 and 30 million st of sand. The five most gravel-rich tracts contain about 71 to 82 percent of the gravel resources in all 20 tracts and about 54-56 percent of the sand. Using this methodology, and the above criteria, a group of four tracts, divided by narrow areas sterilized by a small stream and secondary roads, may have the highest potential in the quadrangle for sand and gravel resources. ?? Springer Science+Business Media, LLC 2006.

  14. Data mining

    Gorunescu, Florin

    2011-01-01

    The knowledge discovery process is as old as Homo sapiens. Until some time ago, this process was solely based on the 'natural personal' computer provided by Mother Nature. Fortunately, in recent decades the problem has begun to be solved based on the development of the Data mining technology, aided by the huge computational power of the 'artificial' computers. Digging intelligently in different large databases, data mining aims to extract implicit, previously unknown and potentially useful information from data, since 'knowledge is power'. The goal of this book is to provide, in a friendly way

  15. Mining wastes

    Pradel, J.

    1981-01-01

    In this article mining wastes means wastes obtained during extraction and processing of uranium ores including production of uraniferous concentrates. The hazards for the population are irradiation, ingestion, dust or radon inhalation. The different wastes produced are reviewed. Management of liquid effluents, water treatment, contamined materials, gaseous wastes and tailings are examined. Environmental impact of wastes during and after exploitation is discussed. Monitoring and measurements are made to verify that ICRP recommendations are met. Studies in progress to improve mining waste management are given [fr

  16. Where on Earth can we find Mars? Characterization of an Aeolian Analogue in Northwestern Argentina

    Favaro, E. A.; Hugenholtz, C.; Barchyn, T.

    2017-12-01

    The Puna Plateau of northwestern Argentina is as a promising analogue for Martian aeolian processes owing to its altitude, low atmospheric pressure, aridity, and widespread granular and bedrock aeolian features. The study was conducted in and surrounding the area known as the Campo de Piedra Pómez - a prominent expanse of wind-carved ignimbrite in Argentina's Catamarca Province. To interpret the evolution of this unique laboratory, which is limited by its isolated location and dearth of in situ measurements, we investigated contemporary aeolian sediment transport through a combination of modeled meteorological data, satellite imagery, field measurements, and sediment traps. Our objective is to utilize modeled meteorological data, satellite imagery, and field measurements and samples to characterize the aeolian environment here to base analogue studies. Satellite imagery from Terra MODIS, GeoEye, and Ikonos indicate recent large-scale aeolian sediment transport events and migration of gravel in the region. A prominent, region-wide sediment transport event on 14 August 2015 coincided with synoptic-scale pressure patterns indicating a strong Zonda (Foehn) winds. Sediment traps and marbles provide additional evidence of wind-driven transport of sand and gravel. Yet, despite the body of evidence for sediment transport on the Puna Plateau, modeled wind data from the European Center for Midrange Weather Forecasting suggest wind rarely attains the speeds necessary to initiate sediment transport. This disconnect is reminiscent of the Martian Saltation Paradox which suggested winds on Mars were incapable of mobilizing sediment, despite widespread evidence from rover, lander, and satellite observations. This raises questions about: (i) the suitability of modeled wind data for characterizing aeolian processes on both planets, and (ii) the possibility that most geomorphic work is conducted in extreme, but infrequent events in this region (possibly analogous to Mars). We

  17. Outer region scaling using the freestream velocity for nonuniform open channel flow over gravel

    Stewart, Robert L.; Fox, James F.

    2017-06-01

    The theoretical basis for outer region scaling using the freestream velocity for nonuniform open channel flows over gravel is derived and tested for the first time. Owing to the gradual expansion of the flow within the nonuniform case presented, it is hypothesized that the flow can be defined as an equilibrium turbulent boundary layer using the asymptotic invariance principle. The hypothesis is supported using similarity analysis to derive a solution, followed by further testing with experimental datasets. For the latter, 38 newly collected experimental velocity profiles across three nonuniform flows over gravel in a hydraulic flume are tested as are 43 velocity profiles previously published in seven peer-reviewed journal papers that focused on fluid mechanics of nonuniform open channel over gravel. The findings support the nonuniform flows as equilibrium defined by the asymptotic invariance principle, which is reflective of the consistency of the turbulent structure's form and function within the expanding flow. However, roughness impacts the flow structure when comparing across the published experimental datasets. As a secondary objective, we show how previously published mixed scales can be used to assist with freestream velocity scaling of the velocity deficit and thus empirically account for the roughness effects that extend into the outer region of the flow. One broader finding of this study is providing the theoretical context to relax the use of the elusive friction velocity when scaling nonuniform flows in gravel bed rivers; and instead to apply the freestream velocity. A second broader finding highlighted by our results is that scaling of nonuniform flow in gravel bed rivers is still not fully resolved theoretically since mixed scaling relies to some degree on empiricism. As researchers resolve the form and function of macroturbulence in the outer region, we hope to see the closing of this research gap.

  18. Run-of-River Impoundments Can Remain Unfilled While Transporting Gravel Bedload: Numerical Modeling Results

    Pearson, A.; Pizzuto, J. E.

    2015-12-01

    Previous work at run-of-river (ROR) dams in northern Delaware has shown that bedload supplied to ROR impoundments can be transported over the dam when impoundments remain unfilled. Transport is facilitated by high levels of sand in the impoundment that lowers the critical shear stresses for particle entrainment, and an inversely sloping sediment ramp connecting the impoundment bed (where the water depth is typically equal to the dam height) with the top of the dam (Pearson and Pizzuto, in press). We demonstrate with one-dimensional bed material transport modeling that bed material can move through impoundments and that equilibrium transport (i.e., a balance between supply to and export from the impoundment, with a constant bed elevation) is possible even when the bed elevation is below the top of the dam. Based on our field work and previous HEC-RAS modeling, we assess bed material transport capacity at the base of the sediment ramp (and ignore detailed processes carrying sediment up and ramp and over the dam). The hydraulics at the base of the ramp are computed using a weir equation, providing estimates of water depth, velocity, and friction, based on the discharge and sediment grain size distribution of the impoundment. Bedload transport rates are computed using the Wilcock-Crowe equation, and changes in the impoundment's bed elevation are determined by sediment continuity. Our results indicate that impoundments pass the gravel supplied from upstream with deep pools when gravel supply rate is low, gravel grain sizes are relatively small, sand supply is high, and discharge is high. Conversely, impoundments will tend to fill their pools when gravel supply rate is high, gravel grain sizes are relatively large, sand supply is low, and discharge is low. The rate of bedload supplied to an impoundment is the primary control on how fast equilibrium transport is reached, with discharge having almost no influence on the timing of equilibrium.

  19. Mining Method

    Kim, Young Shik; Lee, Kyung Woon; Kim, Oak Hwan; Kim, Dae Kyung [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

    1996-12-01

    The reducing coal market has been enforcing the coal industry to make exceptional rationalization and restructuring efforts since the end of the eighties. To the competition from crude oil and natural gas has been added the growing pressure from rising wages and rising production cost as the workings get deeper. To improve the competitive position of the coal mines against oil and gas through cost reduction, studies to improve mining system have been carried out. To find fields requiring improvements most, the technologies using in Tae Bak Colliery which was selected one of long running mines were investigated and analyzed. The mining method appeared the field needing improvements most to reduce the production cost. The present method, so-called inseam roadway caving method presently is using to extract the steep and thick seam. However, this method has several drawbacks. To solve the problems, two mining methods are suggested for a long term and short term method respectively. Inseam roadway caving method with long-hole blasting method is a variety of the present inseam roadway caving method modified by replacing timber sets with steel arch sets and the shovel loaders with chain conveyors. And long hole blasting is introduced to promote caving. And pillar caving method with chock supports method uses chock supports setting in the cross-cut from the hanging wall to the footwall. Two single chain conveyors are needed. One is installed in front of chock supports to clear coal from the cutting face. The other is installed behind the supports to transport caved coal from behind. This method is superior to the previous one in terms of safety from water-inrushes, production rate and productivity. The only drawback is that it needs more investment. (author). 14 tabs., 34 figs.

  20. Design of a deposit of waste materials coming from mining exploitations

    Castro, Alvaro; Pinzon, Hernan; Vargas, William; Pinzon, Andres

    2005-01-01

    This paper presents the design process and stability assessment of a waste backfill in a limestone quarry method. The study shows the geotechnical and mining features of waste and underground materials affected by backfill. The mainly waste materials are: clay, gravel, and blocks of clay stone, sandstone and limestone, all to be disposed by a layered embankment. The constructive method is selected and the stability analysis of deposit and soil foundation was made by equilibrium method without considering deformations

  1. Gravel bars can be critical for biodiversity conservation: a case study on scaly-sided Merganser in South china.

    Qing Zeng

    Full Text Available Gravel bars are characteristic components of river landscapes and are increasingly recognized as key sites for many waterbirds, though detailed studies on the ecological function of gravel bars for waterbirds are rare. In this study, we surveyed the endangered Scaly-sided Merganser Mergus squamatus along a 40 km river section of Yuan River, in Central China, for three consecutive winters. We derived the landscape metrics of river gravel bars from geo-rectified fine resolution (0.6 m aerial image data. We then built habitat suitability models (Generalized Linear Models-GLMs to study the effects of landscape metrics and human disturbance on Scaly-sided Merganser presence probability. We found that 1 the Scaly-sided Merganser tended to congregate at river segments with more gravel patches; 2 the Scaly-sided Merganser preferred areas with larger and more contiguous gravel patches; and 3 the number of houses along the river bank (a proxy for anthropogenic disturbance had significantly negative impacts on the occurrence of the Scaly-sided Merganser. Our results suggest that gravel bars are vital to the Scaly-sided Merganser as shelters from disturbance, as well as sites for feeding and roosting. Therefore, maintaining the exposure of gravel bars in regulated rivers during the low water period in winter might be the key for the conservation of the endangered species. These findings have important implications for understanding behavioral evolution and distribution of the species and for delineating between habitats of different quality for conservation and management.

  2. [Runoff and sediment yielding processes on red soil engineering accumulation containing gravels by a simulated rainfall experiment].

    Shi, Qian-hua; Wang, Wen-long; Guo, Ming-ming; Bai, Yun; Deng, Li-qiang; Li, Jian-ming; Li, Yao-lin

    2015-09-01

    Engineering accumulation formed in production and construction projects is characterized by unique structure and complex material composition. Characteristics of soil erosion on the engineering accumulation significantly differ from those on farmland. An artificially simulated rainfall experiment was carried out to investigate the effects of rainfall intensity on the processes of runoff and sediment yielding on the engineering accumulation of different gravel contents (0%, 10%, 20% and 30%) in red soil regions. Results showed that the initial time of runoff generation decreased with increases in rainfall intensity and gravel content, the decreased amplitudes being about 48.5%-77.9% and 4.2%-34.2%, respectively. The initial time was found to be a power function of rainfall intensity. Both runoff velocity and runoff rate manifested a trend of first rising and then in a steady state with runoff duration. Rainfall intensity was found to be the main factor influencing runoff velocity and runoff rate, whereas the influence of gravel content was not significant. About 10% of gravel content was determined to be a critical value in the influence of gravel content on runoff volume. For the underlying surface of 10% gravel content, the runoff volume was least at rainfall intensity of 1.0 mm · min(-1) and maximum at rainfall intensity of greater than 1.0 mm · min(-1). The runoff volume in- creased 10%-60% with increase in rainfall intensity. Sediment concentration showed a sharp decline in first 6 min and then in a stable state in rest of time. Influence of rainfall intensity on sediment concentration decreased as gravel content increased. Gravels could reduce sediment yield significantly at rainfall intensity of greater than 1.0 mm · min(-1). Sediment yield was found to be a linear function of rainfall intensity and gravel content.

  3. Nuclear Energy Stakeholders in Argentina

    Gadano, Julian

    2017-01-01

    Mr Gadano, Undersecretary for Nuclear Energy, Argentina spoke from the perspective of a country looking forward to becoming a member of the NEA. He reviewed the place of nuclear energy in his country's energy mix and called attention to its role in positively addressing the global challenges of climate change and energy security. Mr Gadano also described the federal system which governs Argentina. Drawing on his expertise as a lawmaker and nuclear regulator but also as an academic sociologist, he stressed that reaching agreement on siting initiatives for example requires a sustainable relation with stakeholders, including regional governments. This is important because in the end, 'the best project is the one you can finish'

  4. Frost Resistance and Permeability of Cement Stabilized Gravel used as Filling Material for Pearl-Chain Bridges

    Lund, Mia Schou Møller; Hansen, Kurt Kielsgaard; Hertz, Kristian Dahl

    2014-01-01

    several requirements on its moisture properties. In this paper the frost resistance, the liquid water permeability and the water vapour permeability of cement stabilized gravel are examined for two different cement contents. It is found that a small increase in cement content from 4% to 5% increases...... the 28-days compressive strength from 6.2 MPa to 12.3 MPa. The frost resistance of cement stabilized gravel with 5% cement content is better than for cement stabilized gravel with 4% cement content. The liquid water permeability coefficient and the water vapour permeability coefficient are significantly...

  5. Public information activities in Argentina

    Espejo, Hector

    1998-01-01

    This is a presentation involving a description of the main guidelines and conditions under which nuclear activities have been performed in Argentina, both concerning the autonomous development for the peaceful use of nuclear energy and with regard to the way in which the community was informed of the attained levels. The particulars of each approach are shown as to delineate historical evolution as a function of the various stages of technological development. (author)

  6. The energy sector in Argentina

    2016-01-01

    This article first outlines that Argentina produces an important part of its hydrocarbon consumption and comment various aspects of this production: hydrocarbons are at the heart of the Argentinian energetic model; conventional hydrocarbon reserves are however decreasing; the public operator remains the main actor even though the market is opened to multinational companies. The article then describes the crisis faced by this energetic model: the energy balance is now a burden; the increasing unbalance between production and consumption can be explained by supply-related as well as demand-related factors; authorities must intervene on hydrocarbon prices and subsidize the oil price on the domestic market. It appears that the future for hydrocarbons in Argentina relies on non-conventional hydrocarbons. Bio-fuels, a key sector of the Argentinian economy, are a matter of trade dispute with the EU and the USA. Apart from hydroelectricity (some new projects are planned), renewable energies are very few developed in Argentina. Appendices propose a graph of the distribution of energy consumption among the different sources, a map indicating locations of the main exploited hydrocarbon deposits, a presentation of mechanisms implemented to subsidize hydrocarbon production

  7. Mine games

    Patchett, A. [Hitachi Construction Equipment (United Kingdom)

    2006-09-15

    The article describes various excavators used in the UK by Hall Construction for coal mining and reclamation projects. They include machines from Hitachi Construction Machinery that have been modified with a coal shovel at the front end. The ZX350LC-3, for example incorporates a coal shovel, manufactured by Kocurek, to allow it to work at the rock face and lift coal into road wagons or dump trucks. 5 figs.

  8. Isotope Investigations of Groundwater Movement in a Coarse Gravel Unsaturated Zone

    Mali, N. [Geological Survey of Slovenia, Department of Hydrogeology, Ljubljana (Slovenia); Kozar-Logar, J. [Jozef Stefan Institute, Ljubljana (Slovenia); Leis, A. [Institute of Water Resources Management, Hydrogeology and Geophysics, Joanneum Research Forschungsgesellschaft mbH, Graz (Austria)

    2013-07-15

    The unsaturated zone above an aquifer serves as a water reservoir which discharges water and possible pollution to the saturated zone. This paper presents the application of oxygen-18 and tritium isotope methods in the study of groundwater transport processes in the unsaturated zone of Selniska Dobrava coarse gravel aquifer. The Selniska Dobrava gravel aquifer is an important water resource for Maribor and its surroundings, therefore the determination of transport processes in the unsaturated zone is important regarding its protection. Groundwater flow characteristics were estimated using isotopes and based on experimental work in a lysimeter. Tritium investigation results were compared with the results of long term oxygen-18 isotope investigation. In this paper the analytical approach, results and interpretation of {delta}{sup 18}O and tritium measurements in the unsaturated zone are presented. (author)

  9. RADIONUCLIDES DISTRIBUTION NEAR FORMER URANIUM MINING

    D. A. Zaredinov

    2016-01-01

    Full Text Available The paper shows, that radionuclides from the stony rocks of uranium mines can be leached by atmospheric precipitations. In acid conditions, a degree of leaching is greater.Goal. The aim of this investigation was to study the distribution of radionuclides in uranium minings and their impact on the environmental contamination.Materials and methods. The study was carried out in two stages. In the first stage, a blade of rock was mixed with distilled water in proportions of 0,3 kg of gravel and 1 liter of water. After thirty days of soaking, water was sent to the gamma-spectrometric analysis to Canberra’s spectrometer (USA with a high-purity germanium detector. In the second stage, we carried out the similar experiment with water, wich was acidified to pH = 3. Contamination levels of areas near the in-situ leaching mine were determined. Intervention levels were used to estimate risk and possible water consumption by the population. Estimations were carried out taking into account the combined presence of several radionuclides in the water.Results. The results of these studies have shown that the distribution of radionuclides from the source of the contamination is about 360 meters during the 30 y period. The stream, along which samples of soil were collected and studied, was formed by the miner waters that flow along small ruts towards a village, thereby increasing the likelihood of water use by the public.Conclusions. The uranium mines are the source of radioactive contamination. Radionuclides are distributed due to the erosion of rocks and leached out of the stony rock by precipitations. The extent of leaching is significantly increased in an acidic environment, which takes place near the in-situ leaching mines.

  10. Environmentalism and natural aggregate mining

    Drew, L.J.; Langer, W.H.; Sachs, J.S.

    2002-01-01

    Sustaining a developed economy and expanding a developing one require the use of large volumes of natural aggregate. Almost all human activity (commercial, recreational, or leisure) is transacted in or on facilities constructed from natural aggregate. In our urban and suburban worlds, we are almost totally dependent on supplies of water collected behind dams and transported through aqueducts made from concrete. Natural aggregate is essential to the facilities that produce energy-hydroelectric dams and coal-fired powerplants. Ironically, the utility created for mankind by the use of natural aggregate is rarely compared favorably with the environmental impacts of mining it. Instead, the empty quarries and pits are seen as large negative environmental consequences. At the root of this disassociation is the philosophy of environmentalism, which flavors our perceptions of the excavation, processing, and distribution of natural aggregate. The two end-member ideas in this philosophy are ecocentrism and anthropocentrism. Ecocentrism takes the position that the natural world is a organism whose arteries are the rivers-their flow must not be altered. The soil is another vital organ and must not be covered with concrete and asphalt. The motto of the ecocentrist is "man must live more lightly on the land." The anthropocentrist wants clean water and air and an uncluttered landscape for human use. Mining is allowed and even encouraged, but dust and noise from quarry and pit operations must be minimized. The large volume of truck traffic is viewed as a real menace to human life and should be regulated and isolated. The environmental problems that the producers of natural aggregate (crushed stone and sand and gravel) face today are mostly difficult social and political concerns associated with the large holes dug in the ground and the large volume of heavy truck traffic associated with quarry and pit operations. These concerns have increased in recent years as society's demand for

  11. Wall roughness effects on flow and scouring in curved channels with gravel bed

    Hersberger, Daniel S.

    2002-01-01

    Wall roughness effects on flow and scouring in curved channels with gravel bed In the narrow valleys in Alpine regions, rivers frequently flow across constructed zones, passing through villages and cities. Due to limited space, the protection from high floods often needs to be ensured by protection walls. During floods, these protection walls may be endangered by scour phenomena, especially if they are located in bends. In the past, the potential danger of underscoured structures was reduced ...

  12. Barrier erosion control test plan: Gravel mulch, vegetation, and soil water interactions

    Waugh, W.J.; Link, S.O. (Pacific Northwest Lab., Richland, WA (USA))

    1988-07-01

    Soil erosion could reduce the water storage capacity of barriers that have been proposed for the disposal of near-surface waste at the US Department of Energy's Hanford Site. Gravel mixed into the top soil surface may create a self-healing veneer that greatly retards soil loss. However, gravel admixtures may also enhance infiltration of rainwater, suppress plant growth and water extraction, and lead to the leaching of underlying waste. This report describes plans for two experiments that were designed to test hypotheses concerning the interactive effects of surface gravel admixtures, revegetation, and enhanced precipitation on soil water balance and plant abundance. The first experiment is a factorial field plot set up on the site selected as a soil borrow area for the eventual construction of barriers. The treatments, arranged in a a split-split-plot design structure, include two densities of gravel admix, a mixture of native and introduced grasses, and irrigation to simulate a wetter climate. Changes in soil water storage and plant cover are monitored with neutron moisture probes and point intercept sampling, respectively. The second experiment consists of an array of 80 lysimeters containing several different barrier prototypes. Surface treatments are similar to the field-plot experiment. Drainage is collected from a valve at the base of each lysimeter tube, and evapotranspiration is estimated by subtraction. The lysimeters are also designed to be coupled to a whole-plant gas exchange system that will be used to conduct controlled experiments on evapotranspiration for modeling purposes. 56 refs., 6 figs., 8 tabs.

  13. Surface particle sizes on armoured gravel streambeds: Effects of supply and hydraulics

    Peter J. Whiting; John G. King

    2003-01-01

    Most gravel-bed streams exhibit a surface armour in which the median grain size of the surface particles is coarser than that of the subsurface particles. This armour has been interpreted to result when the supply of sediment is less than the ability of the stream to move sediment. While there may be certain sizes in the bed for which the supply is less than the...

  14. Compositional Signatures in Acoustic Backscatter Over Vegetated and Unvegetated Mixed Sand-Gravel Riverbeds

    Buscombe, D.; Grams, P. E.; Kaplinski, M. A.

    2017-10-01

    Multibeam acoustic backscatter has considerable utility for remote characterization of spatially heterogeneous bed sediment composition over vegetated and unvegetated riverbeds of mixed sand and gravel. However, the use of high-frequency, decimeter-resolution acoustic backscatter for sediment classification in shallow water is hampered by significant topographic contamination of the signal. In mixed sand-gravel riverbeds, changes in the abiotic composition of sediment (such as homogeneous sand to homogeneous gravel) tend to occur over larger spatial scales than is characteristic of small-scale bedform topography (ripples, dunes, and bars) or biota (such as vascular plants and periphyton). A two-stage method is proposed to filter out the morphological contributions to acoustic backscatter. First, the residual supragrain-scale topographic effects in acoustic backscatter with small instantaneous insonified areas, caused by ambiguity in the local (beam-to-beam) bed-sonar geometry, are removed. Then, coherent scales between high-resolution topography and backscatter are identified using cospectra, which are used to design a frequency domain filter that decomposes backscatter into the (unwanted) high-pass component associated with bedform topography (ripples, dunes, and sand waves) and vegetation, and the (desired) low-frequency component associated with the composition of sediment patches superimposed on the topography. This process strengthens relationships between backscatter and sediment composition. A probabilistic framework is presented for classifying vegetated and unvegetated substrates based on acoustic backscatter at decimeter resolution. This capability is demonstrated using data collected from diverse settings within a 386 km reach of a canyon river whose bed varies among sand, gravel, cobbles, boulders, and submerged vegetation.

  15. Experiences made with tritium-containing water used as tracer in laboratory experiments with fluvioglacial gravels

    Klotz, D.; Rauert, W.

    1982-01-01

    Batch tests performed on 11 different Bavarian fluvioglacial gravels led to tritium distribution coefficients, which deviated not or only insignificantly from zero within the range of experimental accuracy applied to routine testings. The result of nine flow experiments in a gravelfilled column was a mean retardation factor of 1.01 +- 0.01. These experiments thus showed - as it had been expected - that 3 HHO is not significantly delayed with regard to the flow or movement of the water. (orig.) [de

  16. Physical Characteristics of Laboratory Tested Concrete as a Substituion of Gravel on Normal Concrete

    Butar-butar, Ronald; Suhairiani; Wijaya, Kinanti; Sebayang, Nono

    2018-03-01

    Concrete technology is highly potential in the field of construction for structural and non-structural construction. The amount uses of this concrete material raise the problem of solid waste in the form of concrete remaining test results in the laboratory. This waste is usually just discarded and not economically valuable. In solving the problem, this experiment was made new materials by using recycle material in the form of recycled aggregate which aims to find out the strength characteristics of the used concrete as a gravel substitution material on the normal concrete and obtain the value of the substitution composition of gravel and used concrete that can achieve the strength of concrete according to the standard. Testing of concrete characteristic is one of the requirements before starting the concrete mixture. This test using SNI method (Indonesian National Standard) with variation of comparison (used concrete : gravel) were 15: 85%, 25: 75%, 35:65%, 50:50 %, 75: 25%. The results of physical tests obtained the mud content value of the mixture gravel and used concrete is 0.03 larger than the standard of SNI 03-4142-1996 that is equal to 1.03%. so the need watering or soaking before use. The water content test results show an increase in the water content value if the composition of the used concrete increases. While the specific gravity value for variation 15: 85% until 35: 65% fulfilled the requirements of SNI 03-1969-1990. the other variasion show the specifics gravity value included on the type of light materials.

  17. Compositional signatures in acoustic backscatter over vegetated and unvegetated mixed sand-gravel riverbeds

    Buscombe, Daniel; Grams, Paul E.; Kaplinski, Matt A.

    2017-01-01

    Multibeam acoustic backscatter has considerable utility for remote characterization of spatially heterogeneous bed sediment composition over vegetated and unvegetated riverbeds of mixed sand and gravel. However, the use of high-frequency, decimeter-resolution acoustic backscatter for sediment classification in shallow water is hampered by significant topographic contamination of the signal. In mixed sand-gravel riverbeds, changes in the abiotic composition of sediment (such as homogeneous sand to homogeneous gravel) tend to occur over larger spatial scales than is characteristic of small-scale bedform topography (ripples, dunes, and bars) or biota (such as vascular plants and periphyton). A two-stage method is proposed to filter out the morphological contributions to acoustic backscatter. First, the residual supragrain-scale topographic effects in acoustic backscatter with small instantaneous insonified areas, caused by ambiguity in the local (beam-to-beam) bed-sonar geometry, are removed. Then, coherent scales between high-resolution topography and backscatter are identified using cospectra, which are used to design a frequency domain filter that decomposes backscatter into the (unwanted) high-pass component associated with bedform topography (ripples, dunes, and sand waves) and vegetation, and the (desired) low-frequency component associated with the composition of sediment patches superimposed on the topography. This process strengthens relationships between backscatter and sediment composition. A probabilistic framework is presented for classifying vegetated and unvegetated substrates based on acoustic backscatter at decimeter resolution. This capability is demonstrated using data collected from diverse settings within a 386 km reach of a canyon river whose bed varies among sand, gravel, cobbles, boulders, and submerged vegetation.

  18. Suppressing immature house and stable flies in outdoor calf hutches with sand, gravel, and sawdust bedding.

    Schmidtmann, E T

    1991-11-01

    Sand, gravel, sawdust, and pine shavings were used as bedding in outdoor calf hutches and compared with straw relative to the density of immature (maggot) house flies, Musca domestica, and stable flies, Stomoxys calcitrans. In 6-wk field trials, average densities of house and stable fly maggots in concrete mix sand ranged from only .3 to 1.6 and 0 to .1 maggots/L, respectively; pea size gravel bedding also strongly suppressed densities from less than .1 to .3 and less than .1 to .1 maggots/L, respectively. These densities represent reductions of 76 to greater than 99% relative to straw bedding, but both sand and gravel compacted and became soiled with calf feces, which resulted in unacceptable bedding sanitation and foul odors. Densities of house and stable fly maggots in pine shavings did not differ from those in straw bedding. Nevertheless, in sawdust bedding, maggot density was limited to averages of 1.4 to 8.3 house and 9.8 to 11.8 stable fly maggots/L; this represented reductions of 45 to 91% relative to straw. In a follow-up trial, house and stable fly maggot densities in sawdust averaged 11.3 and 43.9 maggots/L, respectively, reductions of 77 and 46%. These findings suggest that bedding calf hutches with sawdust during warm weather can be useful as an ecologically sound approach to controlling muscoid fly populations on dairy farms.

  19. Evaluation of Hydraulic Parameters Obtained by Different Measurement Methods for Heterogeneous Gravel Soil

    Chen Zeng

    2012-01-01

    Full Text Available Knowledge of soil hydraulic parameters for the van Genuchten function is important to characterize soil water movement for watershed management. Accurate and rapid prediction of soil water flow in heterogeneous gravel soil has become a hot topic in recent years. However, it is difficult to precisely estimate hydraulic parameters in a heterogeneous soil with rock fragments. In this study, the HYDRUS-2D numerical model was used to evaluate hydraulic parameters for heterogeneous gravel soil that was irregularly embedded with rock fragments in a grape production base. The centrifugal method (CM, tensiometer method (TM and inverse solution method (ISM were compared for various parameters in the van Genuchten function. The soil core method (SCM, disc infiltration method (DIM and inverse solution method (ISM were also investigated for measuring saturated hydraulic conductivity. Simulation with the DIM approach revealed a problem of overestimating soil water infiltration whereas simulation with the SCM approach revealed a problem of underestimating water movement as compared to actual field observation. The ISM approach produced the best simulation result even though this approach slightly overestimated soil moisture by ignoring the impact of rock fragments. This study provides useful information on the overall evaluation of soil hydraulic parameters attained with different measurement methods for simulating soil water movement and distribution in heterogeneous gravel soil.

  20. Bed Load Variability and Morphology of Gravel Bed Rivers Subject to Unsteady Flow: A Laboratory Investigation

    Redolfi, M.; Bertoldi, W.; Tubino, M.; Welber, M.

    2018-02-01

    Measurement and estimation of bed load transport in gravel bed rivers are highly affected by its temporal fluctuations. Such variability is primarily driven by the flow regime but is also associated with a variety of inherent channel processes, such as flow turbulence, grain entrainment, and bed forms migration. These internal and external controls often act at comparable time scales, and are therefore difficult to disentangle, thus hindering the study of bed load variability under unsteady flow regime. In this paper, we report on laboratory experiments performed in a large, mobile bed flume where typical hydromorphological conditions of gravel bed rivers were reproduced. Data from a large number of replicated runs, including triangular and square-wave hydrographs, were used to build a statistically sound description of sediment transport processes. We found that the inherent variability of bed load flux strongly depends on the sampling interval, and it is significantly higher in complex, wandering or braided channels. This variability can be filtered out by computing the mean response over the experimental replicates, which allows us to highlight two distinctive phenomena: (i) an overshooting (undershooting) response of the mean bed load flux to a sudden increase (decrease) of discharge, and (ii) a clockwise hysteresis in the sediment rating curve. We then provide an interpretation of these findings through a conceptual mathematical model, showing how both phenomena are associated with a lagging morphological adaptation to unsteady flow. Overall, this work provides basic information for evaluating, monitoring, and managing gravel transport in morphologically active rivers.

  1. Synthesis of AL-MCM-41 using gravel drilling the source of silica from wells drilling

    Fontes, M.S.B.; Costa, C.C.; Melo, D.M.A.; Viana, L.M.; Viana, S.O.; Santos, L.M.

    2016-01-01

    The aim of this study was to synthesize Al-MCM-41 using gravel drilling as alternative source of silica, aiming at sustainable production and low cost. For hydrothermal synthesis of Al-MCM-41 was used gravel and sodium silicate as source of silica and sodium, respectively. The structural driver used was cetyltrimethylammonium bromide (CTMABr) and solvent distilled water. The hydrothermal synthesis was conducted at 100 ° C in a Teflon autoclave 45 ml jacketed stainless steel for a period of 120 hours with daily correcting pH (range 9-10) using 30% acetic acid. The material obtained was filtered, washed, dried at 100 ° C for 3 hours and then calcined at 550 ° C for 2 hours. Then it was characterized by XRD, FTIR and TG. For the results of characterization has been observed that the use of the gravel drilling as a source of silica was promising alternative for producing a mesoporous material with a high degree of hexagonal ordering. (author)

  2. Indoor radon in houses built on gravel and sand deposits in southern Finland

    Hutri, K.-L.

    1993-06-01

    Full Text Available Studies by the Finnish Centre for Radiation and Nuclear Safety (STUK have shown that, in Finland, indoor radon concentrations are almost twice as high in houses built on sand or gravel as in houses built on other soil types. The aim of this study was to assess the radon risk on eskers, ice-marginal formations, and other gravel and sand deposits on the basis of factors that can be determined from geological maps. Altogether, 514 houses built on gravel and sand deposits were selected for the study from the indoor radon database of STUK. Several geological parameters were determined. Empirical statistical models were used to assess the significance of factors affecting indoor radon in glaciofluvial deposits and the sand-dominant littoral deposits occurring in association with them. A relationship was found between increased indoor radon concentrations and the location of a house on a steep-sided esker, in the southeastern rapakivi granite area and on the upper slope or top of an esker. The steepness of the slope also increased the radon concentration in houses on steep-sided eskers. The effect of the topographic features is due to subterranean air-flows. As estimated from the very sparse till sampling, the elevated uranium concentration increased the indoor radon concentration only in houses built on littoral deposits around eskers and ice-marginal formations.

  3. Laboratory evidence for short and long-term damage to pink salmon incubating in oiled gravel

    Heintz, R.; Rice, S.; Wiedmer, M.

    1995-01-01

    Pink salmon, incubating in gravel contaminated with crude oil, demonstrated immediate and delayed responses in the laboratory at doses consistent with the concentrations observed in oiled streams in Prince William Sound. The authors incubated pink salmon embryos in a simulated intertidal environment with gravel contaminated by oil from the Exxon Valdez. During the incubation and emergence periods the authors quantified dose-response curves for characters affected directly by the oil. After emergence, fish were coded wire tagged and released, or cultured in netpens. Delayed responses have been observed among the cultured fish, and further observations will be made when coded wire tagged fish return in September 1995. The experiments have demonstrated that eggs need not contact oiled gravel to experience increased mortality, and doses as low as 17 ppb tPAH in water can have delayed effects on growth. A comparison of sediment tPAH concentrations from streams in Prince William Sound with these laboratory data suggests that many 1989 brood pink salmon were exposed to deleterious quantities of oil

  4. Triaxial shear behavior of a cement-treated sand–gravel mixture

    Younes Amini

    2014-10-01

    Full Text Available A number of parameters, e.g. cement content, cement type, relative density, and grain size distribution, can influence the mechanical behaviors of cemented soils. In the present study, a series of conventional triaxial compression tests were conducted on a cemented poorly graded sand–gravel mixture containing 30% gravel and 70% sand in both consolidated drained and undrained conditions. Portland cement used as the cementing agent was added to the soil at 0%, 1%, 2%, and 3% (dry weight of sand–gravel mixture. Samples were prepared at 70% relative density and tested at confining pressures of 50 kPa, 100 kPa, and 150 kPa. Comparison of the results with other studies on well graded gravely sands indicated more dilation or negative pore pressure in poorly graded samples. Undrained failure envelopes determined using zero Skempton's pore pressure coefficient (A¯=0 criterion were consistent with the drained ones. Energy absorption potential was higher in drained condition than undrained condition, suggesting that more energy was required to induce deformation in cemented soil under drained state. Energy absorption increased with increase in cement content under both drained and undrained conditions.

  5. Development of a submerged gravel scrubber for containment venting applications: summary

    Hilliard, R.K.; McCormack, J.D.; Postma, A.K.

    1981-01-01

    Although hypothetical core disruptive accidents (HCDAs) are not design basis accidents for breeder reactor plants, extensive assessments of HCDA consequences have been made and design features for providing margins beyond the design base have been considered for future fast reactor plants. One feature proposed for increasing the safety margin is a containment vent and/or purge system which would mitigate the challenge to containment integrity resulting from excessive temperature and pressure or excessive hydrogen. A cleanup system would be required for removal of vented aerosols and condensible vapors to mitigate radiological consequences to the environment. A study is in progress at HEDL to select and develop a suitable air cleaning system for use in potential breeder reactor containment venting applications. A concept was conceived whereby the passiveness and high loading capacity of a water pool scrubber was combined with the high efficiency of a sand and gravel bed. It was termed a Submerged Gravel Scrubber (SGS). A schematic drawing of the concept is shown. The SGS consists of a bed of gravel (or other packing) submerged in a pool of water

  6. Cement Type Influence on Alkali-Silica Reaction in Concrete with Crushed Gravel Aggregate

    Rutkauskas, A.; Nagrockienė, D.; Skripkiūnas, G.

    2017-10-01

    Alkali-silica reaction is one of the chemical reactions which have a significant influence for durability of concrete. During alkali and silica reaction, silicon located in aggregates of the concrete, reacts with high alkali content. This way in the micropores of concrete is forming hygroscopic gel, which at wet environment, expanding and slowly but strongly destroying concrete structures. The goal of this paper- to determine the influence of cement type on alkali-silica reaction of mortars with crushed gravel. In the study crushed gravel with fraction 4/16 mm was used and four types of cements tested: CEM I 42.5 R; CEM I 42.5 SR; CEM II/A-S 42.5; CEM II/A-V 52.5. This study showed that crushed gravel is low contaminated on reactive particles containing of amorphous silica dioxide. The expansion after 14 days exceed 0.054 %, by RILEM AAR-2 research methodology (testing specimen dimension 40×40×160 mm). Continuing the investigation to 56 days for all specimens occurred alkaline corrosion features: microcracking and the surface plaque of gel. The results showed that the best resistance to alkaline corrosion after 14 days was obtained with cement CEM I 42.5 SR containing ash additive, and after 56 days with cement CEM II/A-V 52.5 containing low alkali content. The highest expansion after 14 and 56 days was obtained with cement CEM I 42.5 R without active mineral additives.

  7. Boll weevil invasion process in Argentina

    The boll weevil, Anthonomus grandis grandis Boheman, is the most destructive cotton pest in the Western Hemisphere. In 1993, the pest was reported in Argentina, and in 1994 boll weevils were captured in cotton fields in the Formosa Province on the border between Argentina and Paraguay. The pest ha...

  8. Communications received from Argentina and Brazil

    1989-01-01

    The document reproduces the Joint Statement on Nuclear Policy signed by the President of Argentina and the President of Brazil on 29 November 1988 at Ezeiza, Argentina, concerning the decision of the two countries to undertake a joint fast breeder reactor project

  9. Mida õpetab Argentina finantskriis? / Karsten Staehr

    Staehr, Karsten, 1962-

    2002-01-01

    Norra majandusanalüütik kirjeldab Argentina majanduspoliitikat, analüüsib tehtud vigu ning hoiatab avatud majandusega Eestit võimalike tulevaste välisshokkide eest. Diagramm: SKP kasv ja üleüldine riigieelarve tasakaal 1991-2001 Argentinas

  10. Reconstructing a sediment pulse: Modeling the effect of placer mining on Fraser River, Canada

    Ferguson, R. I.; Church, M.; Rennie, C. D.; Venditti, J. G.

    2015-07-01

    Gold mining along 525 km of the Fraser River between 1858 and 1909 added an estimated 1.1 × 108 t of tailings, half gravel and the rest finer, to the river's natural sediment load. We simulate the response using a 1-D multigrain size morphodynamic model. Since premining conditions are unknown and modern data are insufficient for tuning the process representation, we devised a novel modeling strategy which may be useful in other data-poor applications. We start the model from a smoothed version of the modern longitudinal profile with bed grain size distributions optimized to match alternative assumptions about natural sediment supply and compare runs that include mining with control runs that can be used to quantify the effects of deficiencies in process representation and initialization. Simulations with an appropriate choice of natural supply rate closely match the best available test data, which consist of a detailed 1952-1999 gravel budget for the distal part of the model domain. The simulations suggest that the main response to mining was rapid bed fining, which allowed a major increase in bed load transport rate with only slight (~0.1 m) mean aggradation within the mining region and most of the excess sediment exported well beyond the mountain front within the mining period or soon afterward. We compare this pattern of response by a large, powerful river with previous case studies of river adjustment to sediment supply change.

  11. Sheet-gravel evidence for a late Holocene tsunami run-up on beach dunes, Great Barrier Island, New Zealand

    Nichol, Scott L.; Lian, Olav B.; Carter, Charles H.

    2003-01-01

    A semi-continuous sheet of granule to cobble-size clasts forms a distinctive deposit on sand dunes located on a coastal barrier in Whangapoua Bay, Great Barrier Island, New Zealand. The gravel sheet extends from the toe of the foredune to 14.3 m above mean sea level and 200 m landward from the beach. Clasts are rounded to sub-rounded and comprise lithologies consistent with local bedrock. Terrestrial sources for the gravel are considered highly unlikely due to the isolation of the dunes from hillslopes and streams. The only source for the clasts is the nearshore to inner shelf of Whangapoua Bay, where gravel sediments have been previously documented. The mechanism for transport of the gravel is unlikely to be storm surge due to the elevation of the deposit; maximum-recorded storm surge on this coast is 0.8 m above mean high water spring tide. Aeolian processes are also discounted due to the size of clasts and the elevation at which they occur. Tsunami is therefore considered the most probable mechanism for gravel transport. Minimum run-up height of the tsunami was 14.3 m, based on maximum elevation of gravel deposits. Optical ages on dune sands beneath and covering the gravel allow age bracketing to 0-4.7 ka. Within this time frame, numerous documented regional seismic and volcanic events could have generated the tsunami, notably submarine volcanism along the southern Kermadec arc to the east-southeast of Great Barrier Island where large magnitude events are documented for the late Holocene. Radiocarbon ages on shell from Maori middens that appear to have been reworked by tsunami run-up constrain the age of this event to post ca. 1400 AD. Regardless of the precise age of this event, the well-preserved nature of the Whangapoua gravel deposit provides for an improved understanding of the high degree of spatial variability in tsunami run-up.

  12. Gravel-Sand-Clay Mixture Model for Predictions of Permeability and Velocity of Unconsolidated Sediments

    Konishi, C.

    2014-12-01

    Gravel-sand-clay mixture model is proposed particularly for unconsolidated sediments to predict permeability and velocity from volume fractions of the three components (i.e. gravel, sand, and clay). A well-known sand-clay mixture model or bimodal mixture model treats clay contents as volume fraction of the small particle and the rest of the volume is considered as that of the large particle. This simple approach has been commonly accepted and has validated by many studies before. However, a collection of laboratory measurements of permeability and grain size distribution for unconsolidated samples show an impact of presence of another large particle; i.e. only a few percent of gravel particles increases the permeability of the sample significantly. This observation cannot be explained by the bimodal mixture model and it suggests the necessity of considering the gravel-sand-clay mixture model. In the proposed model, I consider the three volume fractions of each component instead of using only the clay contents. Sand becomes either larger or smaller particles in the three component mixture model, whereas it is always the large particle in the bimodal mixture model. The total porosity of the two cases, one is the case that the sand is smaller particle and the other is the case that the sand is larger particle, can be modeled independently from sand volume fraction by the same fashion in the bimodal model. However, the two cases can co-exist in one sample; thus, the total porosity of the mixed sample is calculated by weighted average of the two cases by the volume fractions of gravel and clay. The effective porosity is distinguished from the total porosity assuming that the porosity associated with clay is zero effective porosity. In addition, effective grain size can be computed from the volume fractions and representative grain sizes for each component. Using the effective porosity and the effective grain size, the permeability is predicted by Kozeny-Carman equation

  13. MANUAL. Fly ash in civil engineering, Gravel roads; HANDBOK. Flygaska i mark- och vaegbyggnad, Grusvaegar

    Munde, Hanna; Svedberg, Bo; Macsik, Josef; Maijala, Aino; Lahtinen, Pentti; Ekdahl, Peter; Neren, Jens [Vattenfall AB, Stockholm (Sweden). Vaerme Norden

    2006-01-15

    Fly ash based on biofuels or coal has been used as construction material for a long time in roads and other civil engineering applications. Some example, where it has been used in roadbase and subbase of gravel roads, are in the counties of Uppsala, Soedermanland, Vaestmanland and in Finland. The use of fly ash has contributed to good function for example as bearing capacity, thaw and frost capacity and good durability. This has also reduced costs for maintenance. The objective of this project was to develop a manual to provide a base for contemporary use of fly ash in road constructions. In the manual experience from studies, field tests and regulations has been compiled. The manual handles fly ash as base for products to be used in base and subbase in gravel roads. Future user of the guidelines are mainly consultant engineers and contractors. However the aim of the manual is to also support road administrators, environmental authorities and industry. The project has been carried out parallel to another ongoing national project titled 'Guidelines, Use of alternative materials in civil engineering'. The objective of that project is to establish a base for handling of alternative materials in Sweden. Fly ash in gravel roads are mainly used in two typical applications, one without any additive in a single layer and one with fly ash mixed with gravel. The use of flyash provides functional properties such as increased stiffness, stability and enhanced frost and thaw capacity for the road construction in total. Furthermore the products based on fly ash will have low permeability and good frost and thaw durability. These properties are for example related to fly ash quality, design and construction and are in general expected to be better than for traditional constructions using, for example, sand or gravel. The properties can be enhanced further by using binders such as cement and Merit. Fly ash should always be used above the ground water table with

  14. Exploration and Mining Roadmap

    none,

    2002-09-01

    This Exploration and Mining Technology Roadmap represents the third roadmap for the Mining Industry of the Future. It is based upon the results of the Exploration and Mining Roadmap Workshop held May 10 ñ 11, 2001.

  15. Ghana Mining Journal

    ... in the Ghana mining journal: Geology and Mineral Exploration, Mining, Quarrying, Geomechanics, Groundwater Studies, Hydrocarbon Development, Mineral Processing, Metallurgy, Material Science, Mineral Management Policies, Mineral Economics, Environmental Aspects, Computer Applications and Mining Education.

  16. Coal Mine Permit Boundaries

    Earth Data Analysis Center, University of New Mexico — ESRI ArcView shapefile depicting New Mexico coal mines permitted under the Surface Mining Control and Reclamation Act of 1977 (SMCRA), by either the NM Mining these...

  17. Uranium mining in Australia

    Anon.

    1984-01-01

    The mining of uranium in Australia is criticised in relation to it's environmental impact, economics and effects on mine workers and Aborigines. A brief report is given on each of the operating and proposed uranium mines in Australia

  18. Seasonal movement change of sediments using RFID tracer monitoring in composite gravel beach, west coast of Korea

    Han, M.; Yu, J.; Yang, D. Y.; Kim, J. W.

    2017-12-01

    The purpose of this study is to investigate seasonal movement patterns of gravel movements on the west coast of Korean peninsula. This study aims improve understanding of the process of coastal sediments movement and contribute to coastal erosion management. The study site is Taean Bangpo Beach, which is characterized by its macro tide and composite gravel beach (CGB). In this study, we carried out a radio frequency identifier (RFID) tracer movement monitoring experiment. Four hundred tracers, similar in size and shape to beach sediment, were inserted into the beach in February and December 2015. From the results, it was confirmed that generally, gravel moved southward in the winter and northward in the summer. It was also confirmed that the gravel moved long distances in the summer and winter, but much shorter distances in the spring. At the end of the results, it is confirmed that the tracer recovery rate in summer is lower than in winter. Bangpo Beach was influenced by strong wind and wave energy driven by the East Asian winter monsoon, and by normal tidal energy during the other seasons. It means that seasonal variation of gravel movement in the beach is attributed to the difference of seasonal energy conditions. In addition, it is interpreted that the sand at the intertidal zone cannot be removed in the summer when the wave energy is weak, causing the tracer to be buried. This study is expected to contribute to the study of composite gravel beach and coastal coarse sediment movement which have been lacking in research.

  19. Mining royalties

    Jelenković Rade J.

    2014-01-01

    Full Text Available Mineral resources are finite and nonrenewable in the sense that their extraction permanently depletes a country's resource inventory. The role of governments should be to manage the exploitation of these resources to maximize the economic benefits to their community, consistent with the need to attract and retain the exploration and development capital necessary to continue to realize these benefits for as long as possible. In designing mineral sector taxation systems, policy makers must carefully seek to balance tax types, rates, and incentives that satisfy the needs of both the nation and the mining investor.

  20. Greenstone: uso actual en Argentina

    Marcela Fushimi

    2018-04-01

    Full Text Available Este trabajo presenta las características e historia del software para crear y gestionar bibliotecas digitales Greenstone, desarrollado inicialmente por la Universidad de Waikato, Nueva Zelandia en 1997. En primer lugar, se describe la comunidad de usuarios a nivel global, focalizando en el uso actual que el software ha alcanzado en Argentina: la cantidad de implementaciones disponibles, su evolución, el tipo, tamaño y variedad de los desarrollos existentes, así como su aplicación a la gestión de repositorios digitales de ciencia y tecnología en el ámbito de las instituciones científicas, tecnológicas y de educación superior en Argentina. En segundo lugar, se detallan las acciones llevadas a cabo a partir de la creación del Centro Nacional de Promoción de Greenstone en Argentina en 2009. Datos recabados en encuestas realizadas permitieron observar que las razones predominantes para elegir esta plataforma fueron, entre otras, su facilidad de instalación y configuración, su bajo nivel de requerimiento tecnológico, la generalizada escasez de recursos humanos dedicados a esta actividad, y la complejidad que presentaban los softwares alternativos existentes en ese momento. A lo largo de estos 8 años, tanto los repositorios digitales como los sistemas que los soportan evolucionaron drásticamente, modificando el escenario actual. Paralelamente, en 2016 la nueva versión mayor de Greenstone implementó una reingeniería completa del software para su adaptación a las tecnologías en uso: XML, XSLT, Web-services y Java. Como consecuencia de esto, la comunidad de desarrollo local se plantea nuevos desafíos para la migración de las bibliotecas digitales y repositorios implementados con versiones anteriores.

  1. Bioceres: AG Biotechnology from Argentina

    Roberto Feeney

    2016-04-01

    Full Text Available In this case we present a business decision-making situation in which the CEO of an Argentine Ag Biotech company, Bioceres, has to decide the best way to commercialize a new drought-tolerant transgenic technology. The company was founded by twenty three farmers, who shared a common dream that Argentina could become a benchmark in the development of Ag biotechnology. The case has strategic and financial implications, as well as decision-making situation involving a joint venture with an American biotechnology company. It also introduces to discussion the business models of Ag biotechnology companies in developing countries.

  2. Soybean biomass produced in Argentina

    Semino, Stella Maris; Paul, Helena; Tomei, Julia

    2009-01-01

    Soybean biomass for biodiesel, produced in Argentina amongst other places, is considered by some to reduce greenhouse gas emissions and mitigate climate change when compared with fossil fuel. To ensure that the production of biofuels is ‘sustainable', EU institutions and national governments...... are currently designing certification schemes for the sustainable production of biomass. This paper questions the validity of proposed environmental standards, using the production of Argentine soybean as a case study. The production of soybean production is associated with profound environmental impacts...

  3. Achieving the projected capacity of the Stanyantsi mine

    Dragiev, D

    1979-07-01

    Equipment includes 2 Skoda excavators, one Skoda E-25 power shovel, KraZ dump trucks, graders and S-100 bulldozers. The annual production of 700,000 tons is consumed by the Maritsa-Iztok 2 power plant. To increase production and eventually achieve the originally projected output of 1,400,000 tons annually it is necessary to procure an ESh-10/70 power shovel for surface work, employ all available excavating equipment in surface mining and complete an estimate of all needed mining equipment. The new exploitation plan calls for a reorganization of surface levels, realignment of surface drainage, arrangements for employment of two conveyor belts, construction of a service base for the ESh-10/70 power shovel, training of operators and maintenance crews for the ESh-10/70 power shovel, installation of new electric lines and substations and resurfacing access roads with gravel.

  4. Ecofriendly bricks elaborated from coal waste of Moroccan Jerrada Mining

    Ez-zaki H.

    2018-01-01

    Full Text Available Solid waste generated during mining is one of the major environmental problems associated with this industrial activity. The best solution to overcome the environmental impact of this waste is to find recycling facilities in mass-produced products that can absorb the large quantities of these available byproducts. The present study shows the feasibility of using the coal waste of Moroccan Jerrada mining in the production of ecological brick. The first step consists of consecutive stages of crushing, grinding and heating at 650°C of the coal waste with a small amount of lime in order to promote the reactive products of elaborated binders. The second step of the process consists of mixing treated coal waste with a small amount of marble dust, sand, gravel, and water, then pressed and dried at room temperature to manufacture a laboratory ecofriendly bricks. The mechanical strength and thermal conductivity are investigated.

  5. Vascular riffle flora of Appalachian streams: the ecology and effects of acid mine drainage on Justificia americana (L. ) Vahl

    Koryak, M.; Reilly, R.J.

    1984-06-01

    Justicia americana is a stout-based colonial plant, abundant in most of the larger, low to moderate gradient streams of the upper Ohio River basin. The distribution of J. americana is related to acid drainage from bituminous coal mining operations in the upper Ohio River drainage basin. Possible fluvial and biological consequences of the colonization or absence of Justicia are considered. Luxuriant growths were noted on gravel bars and riffles of larger, unpolluted streams in the basin. Acid mine drainage severely depresses the growth of the plant, leaving gravel shoals and riffles in the acid streams either barren or dominated by other emergent species. Particular among these new species is Elecocharis acicularis. The elimination of J. americana from suitable habitat adversely affects channel morphology, substrate composition, general aesthetic quality and aquatic stream life in the region. 16 references, 2 figures, 3 tables.

  6. Education in acoustics in Argentina

    Miyara, Federico

    2002-11-01

    Over the last decades, education in acoustics (EA) in Argentina has experienced ups and downs due to economic and political issues interfering with long term projects. Unlike other countries, like Chile, where EA has reached maturity in spite of the acoustical industry having shown little development, Argentina has several well-established manufacturers of acoustic materials and equipment but no specific career with a major in acoustics. At the university level, acoustics is taught as a complementary--often elective--course for careers such as architecture, communication engineering, or music. In spite of this there are several research centers with programs covering environmental and community noise, effects of noise on man, acoustic signal processing, musical acoustics and acoustic emission, and several national and international meetings are held each year in which results are communicated and discussed. Several books on a variety of topics such as sound system, architectural acoustics, and noise control have been published as well. Another chapter in EA is technical and vocational education, ranging between secondary and postsecondary levels, with technical training on sound system operation or design. Over the last years there have been several attempts to implement master degrees in acoustics or audio engineering, with little or no success.

  7. Gravel bar thermal variability and its potential consequences for CO2 evasion from Alpine coldwater streams

    Boodoo, Kyle; Battin, Tom; Schelker, Jakob

    2017-04-01

    Gravel bars (GB) are ubiquitous in-stream structures with relatively large exposed surfaces, capable of absorbing heat and possibly acting as a heat source to the underlying hyporheic zone (HZ). The distinctive mixing of groundwater and surface water within their HZ largely determines its characteristic physical and biogeochemical properties, including temperature distribution. To study thermal variability within GBs and its possible consequences for CO2 evasion fluxes we analysed high frequency spatio-temporal data for a range of stream and atmospheric physical parameters including the vertical GB temperature, in an Alpine cold water stream (Oberer Seebach, Austria) over the course of a year. We found the vertical temperature profiles within the GB to vary seasonally and with discharge. We extended our study to 13 other gravel bars of varying physical characteristics within the surrounding Ybbs and Erlauf catchments, conducting diurnal spot samplings in summer 2016. Temperatures within the observed permanently wetted hyporheic zone (-56 to -100cm depth below GB surface) of the OSB, were warmer than both end members, surface water and groundwater >18% of the year, particularly during summer. There was a general increase in exceedance within the periodically wetted gravel bar sediment toward the gravel bar surface, further evidencing downward heat transfer to the wetted HZ. Average CO2 flux from the GB was significantly higher than that of streamwater during summer and winter, with significantly higher temperatures and CO2 outgassing rates occurring at the GB tail as compared to streamwater and the head and mid of the GB throughout the year. Higher cumulative (over 6 h) GB seasonal temperatures were associated with increased CO2 evasion fluxes within the OSB, particularly during summer. This enhanced CO2 flux may result from the input of warmer CO2-rich groundwater into the HZ in autumn, while downward heat transfer in summer may enhance GB metabolism and therefore

  8. Experience with two pipeline river crossings in Argentina

    Yaremko, Eugene [Northwest Hydraulic Consultants (NHC), Edmonton (Canada); D' Agnillo, Pablo; Diaz, Jose A. [Minera Alumbrera XTRADA Copper S.A., Buenos Aires (Argentina); Bravo, Claudio

    2009-12-19

    The Alumbrera copper-gold mine located in the Province of Catamarca, northwest region of Argentina, commenced operation in October, 1997. Mine development included a 316 km long, 175 mm diameter slurry pipeline that conveys copper concentrate to a dewatering facility near the city of Tucuman, Province of Tucuman. It became apparent during the first few years of operation that, given the many potential risks of pipeline exposure associated with stream crossings, Minera Alumbrera would have to undertake an aggressive, formal program of risk management of crossings and risk mitigation. In this paper, the experience associated with two crossings is addressed: Rio Villavil; and, Rio Gastona. The original pipeline route through the 10 km length of pipeline connecting Pump Station (PS) 2 to PS 3 was directed along the bottom of the Rio Villavil valley, with most of it located within the flood way of the stream. The exposure of the pipeline at some locations and high risk of further pipeline exposures led to initiation of risk mitigation planning. Remediation work was completed by 2008. Rio Gastona, during the summer of 2001, experienced rapid shifting of the left bank at the crossing resulting in an undermined and unsupported length of pipeline. The subsequent risk mitigation method adopted in 2001 involved the planning and construction of groyne fields along both banks. (author)

  9. Treatment of heavy metals by iron oxide coated and natural gravel media in Sustainable urban Drainage Systems.

    Norris, M J; Pulford, I D; Haynes, H; Dorea, C C; Phoenix, V R

    2013-01-01

    Sustainable urban Drainage Systems (SuDS) filter drains are simple, low-cost systems utilized as a first defence to treat road runoff by employing biogeochemical processes to reduce pollutants. However, the mechanisms involved in pollution attenuation are poorly understood. This work aims to develop a better understanding of these mechanisms to facilitate improved SuDS design. Since heavy metals are a large fraction of pollution in road runoff, this study aimed to enhance heavy metal removal of filter drain gravel with an iron oxide mineral amendment to increase surface area for heavy metal scavenging. Experiments showed that amendment-coated and uncoated (control) gravel removed similar quantities of heavy metals. Moreover, when normalized to surface area, iron oxide coated gravels (IOCGs) showed poorer metal removal capacities than uncoated gravel. Inspection of the uncoated microgabbro gravel indicated that clay particulates on the surface (a natural product of weathering of this material) augmented heavy metal removal, generating metal sequestration capacities that were competitive compared with IOCGs. Furthermore, when the weathered surface was scrubbed and removed, metal removal capacities were reduced by 20%. When compared with other lithologies, adsorption of heavy metals by microgabbro was 10-70% higher, indicating that both the lithology of the gravel, and the presence of a weathered surface, considerably influence its ability to immobilize heavy metals. These results contradict previous assumptions which suggest that gravel lithology is not a significant factor in SuDS design. Based upon these results, weathered microgabbro is suggested to be an ideal lithology for use in SuDS.

  10. Sistema de salud de Argentina The health system of Argentina

    Mariana Belló

    2011-01-01

    Full Text Available En este artículo se describe el sistema de salud de Argentina, que está compuesto por tres sectores: público, de seguridad social y privado. El sector público está integrado por los ministerios nacional y provincial, y la red de hospitales y centros de salud públicos que prestan atención gratuita a toda persona que lo demande, fundamentalmente a personas sin seguridad social y sin capacidad de pago. Se financia con recursos fiscales y recibe pagos ocasionales de parte del sistema de seguridad social cuando atiende a sus afiliados. El sector del seguro social obligatorio está organizado en torno a las Obras Sociales (OS, que aseguran y prestan servicios a los trabajadores y sus familias. La mayoría de las OS operan a través de contratos con prestadores privados y se financian con contribuciones de los trabajadores y patronales. El sector privado está conformado por profesionales de la salud y establecimientos que atienden a demandantes individuales, a los beneficiarios de las OS y de los seguros privados. Este sector también incluye entidades de seguro voluntario llamadas Empresas de Medicina Prepaga que se financian sobre todo con primas que pagan las familias y/o las empresas. En este trabajo también se describen las innovaciones recientes en el sistema de salud, incluyendo el Programa Remediar.This paper describes the health system of Argentina.This system has three sectors: public, social security and private.The public sector includes the national and provincial ministries as well as the network of public hospitals and primary health care units which provide care to the poor and uninsured population. This sector is financed with taxes and payments made by social security beneficiaries that use public health care facilities. The social security sector or Obras Sociales (OS covers all workers of the formal economy and their families. Most OS operate through contracts with private providers and are financed with payroll

  11. The morphodynamics and internal structure of intertidal fine-gravel dunes: Hills Flats, Severn Estuary, UK

    Carling, P. A.; Radecki-Pawlik, A.; Williams, J. J.; Rumble, B.; Meshkova, L.; Bell, P.; Breakspear, R.

    2006-01-01

    In the macrotidal Severn estuary, UK, the dynamics of intertidal fine-gravel dunes were investigated. These dunes are migrating across a bedrock platform. Systematic observations were made of hydraulic climate, geometry, migration rates and internal sedimentary structures of the dunes. During spring tides, the ebb flow is dominant, dunes grow in height and have ebb orientated geometry with bedrock floors in the troughs. During neap tides, a weak flood flow may dominate. Dunes then are flood orientated or symmetrical. Neap dune heights decrease and the eroded sediment is stored in the dune troughs where the bedrock becomes blanketed by muddy gravel. During spring tides, instantaneous bed shear stresses reach 8 N m - 2 , sufficient to disrupt a 9 mm-gravel armour layer. However, a sustained bed shear stress of 4 N m - 2 is required to initiate dune migration at which time the critical depth-mean velocity is 1 m s - 1 . Ebb and flood inequalities in the bed shear stress explain the changes in dune asymmetry and internal structures. During flood tides, the crests of the dunes reverse such that very mobile sedimentary 'caps' overlie a more stable dune 'core'. Because ebb tides dominate, internal structures of the caps often are characterised by ebb orientated steep open-work foresets developed by strong tidal currents and some lower angle crossbeds deposited as weaker currents degrade foresets. The foresets forming the caps may be grouped into cosets (tidal bundles) and are separated from mud-infused cores of crossbeds that lie below, by reactivation and erosion surfaces blanketed by discontinuous mud drapes. The cores often exhibit distinctive muddy toe sets that define the spacing of tidal cosets.

  12. Sorption of activation products on London clay and Dungeness aquifer gravel

    Baston, G.M.N.; Berry, J.A.; Littleboy, A.K.; Pilkington, N.J. (AEA Decommissioning and Radwaste, Harwell Lab. (United Kingdom))

    1992-01-01

    The sortpion of a series of activation-product radionuclides onto London clay and Dungeness aquifer gravel from the nuclear reactor sites at Bradwell and Dungeness, has been examined. Batch sorption and through-diffusion experiments with clay determined chlorine as the chloride ion to be effectively non-sorbing; calcium to be weakly sorbing, whereas cobalt, nickel, niobium and samarium were moderately to strongly sorbing and silver was strongly sorbing. Distribution ratios (R[sub D] values) for Nb, Sm and Ag were found to have a strong dependence on the liquid-solid separation technique employed. The presence of high concentrations of calcium hydroxide led to lower values of R[sub D] for radioactive Ca but higher R[sub D] values for Sm and Ag. The sorption of Ni showed no apparent dependence on groundwater composition at low levels of dissolved organic carbon (DOC). The values of R[sub D] for Co decreased as the DOC content was increased by addition of humic materials. Batch sorption studies with aquifer gravel demonstrated that Ca is weakly sorbing whereas Nb, Ag and Eu are moderately to strongly sorbing. R[sub D] values for Ca and for Ag under neutral pH conditions show little sensitivity to the liquid/solid separation technique used. However, R[sub D] values for Nb and Eu under neutral pH conditions and for Ag in alkaline solution (pH = 11 - 12) show a marked effect. The aquifer gravel was found to be highly inhomogeneous unlike the clay and sorption was greatest on samples with a high proportion of sand, reflecting the clay mineral content. (orig.).

  13. Sorption of activation products on London clay and Dungeness aquifer gravel

    Baston, G.M.N.; Berry, J.A.; Littleboy, A.K.; Pilkington, N.J.

    1992-01-01

    The sortpion of a series of activation-product radionuclides onto London clay and Dungeness aquifer gravel from the nuclear reactor sites at Bradwell and Dungeness, has been examined. Batch sorption and through-diffusion experiments with clay determined chlorine as the chloride ion to be effectively non-sorbing; calcium to be weakly sorbing, whereas cobalt, nickel, niobium and samarium were moderately to strongly sorbing and silver was strongly sorbing. Distribution ratios (R D values) for Nb, Sm and Ag were found to have a strong dependence on the liquid-solid separation technique employed. The presence of high concentrations of calcium hydroxide led to lower values of R D for radioactive Ca but higher R D values for Sm and Ag. The sorption of Ni showed no apparent dependence on groundwater composition at low levels of dissolved organic carbon (DOC). The values of R D for Co decreased as the DOC content was increased by addition of humic materials. Batch sorption studies with aquifer gravel demonstrated that Ca is weakly sorbing whereas Nb, Ag and Eu are moderately to strongly sorbing. R D values for Ca and for Ag under neutral pH conditions show little sensitivity to the liquid/solid separation technique used. However, R D values for Nb and Eu under neutral pH conditions and for Ag in alkaline solution (pH = 11 - 12) show a marked effect. The aquifer gravel was found to be highly inhomogeneous unlike the clay and sorption was greatest on samples with a high proportion of sand, reflecting the clay mineral content. (orig.)

  14. Uranium mining

    Cheeseman, E.W.

    1980-01-01

    The international uranium market appears to be currently over-supplied with a resultant softening in prices. Buyers on the international market are unhappy about some of the restrictions placed on sales by the government, and Canadian sales may suffer as a result. About 64 percent of Canada's shipments come from five operating Ontario mines, with the balance from Saskatchewan. Several other properties will be producing within the next few years. In spite of the adverse effects of the Three Mile Island incident and the default by the T.V.A. of their contract, some 3 600 tonnes of new uranium sales were completed during the year. The price for uranium had stabilized at US $42 - $44 by mid 1979, but by early 1980 had softened somewhat. The year 1979 saw the completion of major environmental hearings in Ontario and Newfoundland and the start of the B.C. inquiry. Two more hearings are scheduled for Saskatchewan in 1980. The Elliot Lake uranium mining expansion hearings are reviewed, as are other recent hearings. In the production of uranium for nuclear fuel cycle, environmental matters are of major concern to the industry, the public and to governments. Research is being conducted to determine the most effective method for removing radium from tailings area effluents. Very stringent criteria are being drawn up by the regulatory agencies that must be met by the industry in order to obtain an operating licence from the AECB. These criteria cover seepages from the tailings basin and through the tailings retention dam, seismic stability, and both short and long term management of the tailings waste management area. (auth)

  15. Argentina to fully privatize state owned YPF

    Anon.

    1992-01-01

    Argentina's Congress has voted to fully privatize state petroleum company Yacimientos Petroliferos Fiscales (YPF), a move the government expects to net at least $8 billion. Despite some political opposition, the vote was 119-10 in favor, with one abstention and opposition party members refusing to participate in the vote. Argentina's President Carlos Menem had threatened to authorize YPF privatization by decree if there was no quorum for a vote. YPF is responsible for 40% of Argentina's oil production. The country h as been self-sufficient in crude since 1982. Current production is 563,472 b/d, and proved reserves of oil and gas are valued at $7 billion

  16. Alternatives to conventional gravel wearing courses on low volume rural roads: Phase 1

    Paige-Green, P

    2003-01-01

    Full Text Available Adviser Abstract Gundo Lashu, the ‘Labour Intensive Rural Roads Maintenance Programme’ that is currently being implemented in Limpopo Province, South Africa has set out to train 24 emerging contractors in rehabilitation of rural gravel roads. All.... The proposal is to treat the in situ materials and sand with a diluted emulsion and a nominal cement application (to assist with breaking of the emulsion) and surface the road with an Otta seal. The aggregate for the Otta seal can be obtained form...

  17. Fluvial sediment inputs to upland gravel bed rivers draining forested catchments: potential ecological impacts

    S. D. Marks

    1997-01-01

    Full Text Available As identified by the detailed long-term monitoring networks at Plynlimon, increased sediment supply to upland fluvial systems is often associated with forestry land-use and practice. Literature is reviewed, in the light of recent results from Plynlimon sediment studies, to enable identification of the potential ecological impacts of fluvial particulate inputs to upland gravel bed rivers draining forested catchments similar to the headwaters of the River Severn. Both sediment transport and deposition can have significant impacts upon aquatic vertebrates, invertebrates and plants.

  18. Sodium fire aerosol loading capacity of several sand and gravel filters

    Barreca, J.R.; McCormack, J.D.

    1980-04-01

    Improved specific loading capacity for sodium fire aerosols was the objective of a sand and gravel test series. The aerosol capacity and related differential pressure of eight aggregate filters is presented. A maximum specific aerosol capacity, for dry aerosol, of 2.4 kg (Na) m -2 was obtained. This filter was loaded to a final differential pressure of 2.6 kPa. The average superficial face velocity was 0.5 cm/s and the average efficiency was 99.8%. The test results indicate that filter capacity increases with aerosol moisture content and with decreasing superficial velocity

  19. The diagnosis of old gravel aspiration in adults by MDCT: a case report

    Kim, Mi Young; Lee, Ki Yeol; Seo, Bo Kyoung; Kim, Je Hyeong; Jung, Ki Hwan [Ansan Hospital, Korea University Medical Center, Ansan (Korea, Republic of)

    2008-03-15

    We report a case of old gravel aspiration in a 57-year-old man who had been accidentally buried in a field of construction for ten hours, three years prior. A chest radiograph showed peribronchial pneumonic infiltrates in the right lower lobe, with a proximal ovoid radiopaque endobronchial density at the trunchus basalis. These findings were more clearly visualized on the 64-channel multidetector CT (MDCT). Moreover, the patient recovered from his condition, following a bronchoscopic retrieval. However, the patient had persistent bronchiectasis of the right lower lobe on a subsequent follow-up chest radiograph, one month later.

  20. Strategies for the implementation of an environmental mining plan of the construction materials in Bogota. Phase 1 Diagnostic

    Gonzalez Oviedo, Leopoldo; Parrado L, Guillermo; Cardenas, John Fernan

    1995-01-01

    The study contains the geologic aspects, miners and environmental of 10 areas selected in Bogota where construction materials exist, like they are sands, clays, and gravels, in each area a definition is made, the productive units are described, reserves, mining production and environmental impacts are given generated by the material exploitation; a prioritizing of potential areas is included to implement a miner-environmental plan of this industry in Bogota

  1. Kiruna research mine

    Oestensen, A

    1983-12-01

    The research mine at Kiruna is the first large-scale mining research project sponsored by the Swedish government. Under the leadership of the Swedish Mining Research Foundation, a five-year project involving development of new mining systems and machinery will be carried out in cooperation with the Lulea Institute of Technology and a number of Swedish industrial companies.

  2. Application for trackless mining technique in Benxi uranium mine

    Chen Bingguo

    1998-01-01

    The author narrates the circumstances achieving constructional target in Benxi Uranium Mine under relying on advance of science and technology and adopting small trackless mining equipment, presents the application of trackless mining equipment at mining small mine and complex mineral deposit and discusses the unique superiority of trackless mining technique in development work, mining preparation work and backstoping

  3. Soft Asphalt and Double Otta Seal—Self-Healing Sustainable Techniques for Low-Volume Gravel Road Rehabilitation

    Audrius Vaitkus

    2018-01-01

    Full Text Available Increased traffic flow on low-volume gravel roads and deficiencies of national road infrastructure, are increasingly apparent in Lithuania. Gravel roads do not comply with requirements, resulting in low driving comfort, longer travelling time, faster vehicle amortization, and dustiness. The control of dustiness is one of the most important road maintenance activities on gravel roads. Another important issue is the assurance of required driving comfort and safety. Soft asphalt and Otta Seal technologies were proposed as a sustainable solution for the improvement of low-volume roads in Lithuania. Five gravel roads were constructed with soft asphalt, and 13 gravel roads were sealed with double Otta Seal, in 2012. The main aim of this research was to check soft asphalt and double Otta Seal’s ability to self-heal, on the basis of the results of the qualitative visual assessment of pavement defects and distress. The qualitative visual assessment was carried out twice a year following the opening of the rehabilitated road sections. The results confirmed soft asphalt and double Otta Seal’s ability to self-heal. The healing effect was more than 13% and 19% on roads with soft asphalt and double Otta Seal, respectively. In addition, on some roads, all cracks observed in spring self-healed during summer.

  4. Environmental geologic analysis of Rio de las Taguas basin Departmento Iglesia San Juan Argentina

    Arroqui Langer, A.; Cardus, A.; Sindern, S.; Nozica, G.

    2007-01-01

    A mineral environmental research project results where it has been located in Rio de las Taguas basin, Departamento Iglesia, Provincia de San Juan, Argentina. It has been placed in frontal Andean mountain in San Juan. In this geographic framework has been developed Au and Ag mineral project in order the world scale. The aim of this article is has been related the mineral and geological units bet wen the basin chemistry as well as to carry out future measurements mines impacts in this area. (author)

  5. Measured radon inside housings the Republic Argentina

    Canoba, A.; Arnaud, M.; Lopez, F.; Oliveira, A.A.

    1998-01-01

    They have been measured the radon concentration in houses in different city's in Argentina Republic. For they were used it as method mensuration detectors appearances nuclear detecting electrets and detectors based on the adsorption radon in activated carbon

  6. Nuclear Data in Argentina (1992 -1993)

    Ricabarra, G. H.

    1993-03-01

    A progress report of nuclear data research in Argentina is given for the years 1992/1993, including the WIMS nuclear data library update project, and measurements and evaluations of selected neutron induced nuclear reactions. (author)

  7. The timing of scour and fill in a gravel-bedded river measured with buried accelerometers

    Gendaszek, Andrew S.; Magirl, Christopher S.; Czuba, Christiana R.; Konrad, Christopher P.

    2013-01-01

    A device that measures the timing of streambed scour and the duration of sediment mobilization at specific depths of a streambed was developed using data-logging accelerometers placed within the gravel substrate of the Cedar River, Washington, USA. Each accelerometer recorded its orientation every 20 min and remained stable until the surrounding gravel matrix mobilized as sediment was transported downstream and scour reached the level of the accelerometer. The accelerometer scour monitors were deployed at 26 locations in salmon-spawning habitat during the 2010–2011 flood season to record when the streambed was scoured to the depth of typical egg-pocket deposition. Scour was recorded at one location during a moderate high-flow event (65 m3/s; 1.25–1.5-year recurrence interval) and at 17 locations during a larger high-flow event (159 m3/s; 7-year recurrence interval). Accelerometer scour monitors recorded periods of intermittent sediment mobilization and stability within a high-flow event providing insight into the duration of scour. Most scour was recorded during the rising limb and at the peak of a flood hydrograph, though some scour occurred during sustained high flows following the peak of the flood hydrograph.

  8. Large submarine sand waves and gravel lag substrates on Georges Bank off Atlantic Canada

    Todd, B.J.; Valentine, Page C.; Harris, Peter T; Baker, E.K.

    2012-01-01

    Georges Bank is a large, shallow, continental shelf feature offshore of New England and Atlantic Canada. The bank is mantled with a veneer of glacial debris transported during the late Pleistocene from continental areas lying to the north. These sediments were reworked by marine processes during postglacial sea-level transgression and continue to be modified by the modern oceanic regime. The surficial geology of the Canadian portion of the bank is a widespread gravel lag overlain in places by well sorted sand occurring as bedforms. The most widespread bedforms are large, mobile, asymmetrical sand waves up to 19 m in height formed through sediment transport by strong tidal-driven and possibly storm-driven currents. Well-defined curvilinear bedform crests up to 15 km long form a complex bifurcating pattern having an overall southwest–northeast strike, which is normal to the direction of the major axis of the semidiurnal tidal current ellipse. Minor fields of immobile, symmetrical sand waves are situated in bathymetric lows. Rare mobile, asymmetrical barchan dunes are lying on the gravel lag in areas of low sand supply. On Georges Bank, the management of resources and habitats requires an understanding of the distribution of substrate types, their surface dynamics and susceptibility to movement, and their associated fauna.

  9. Soil erosion rates from mixed soil and gravel surfaces in a wind tunnel: A preliminary report

    Ligotke, M.W.

    1988-12-01

    Tests of wind erosion were performed in a controlled-environment wind tunnel to support the development of natural-material protective barriers for long-term isolation of radioactive waste. Barrier performance standards currently being developed for internal and external barrier performance are expected to mandate a surface layer that is resistant to wind erosion. The purpose of this study was to initiate a series of tests to determine suitable soil and gravel mixtures for such a barrier and to test worst-case surface layer conditions under the influence of high wind speeds. Six mixed soil and gravel surfaces were prepared, weathered to represent natural wind-blown desert areas, and subjected to controlled wind erosion forces in a wind tunnel. The applied erosive forces, including surface shear forces, were characterized to provide a means of relating wind tunnel results with actual field conditions. Soil particle losses from the surfaces caused by suspension, saltation, and surface creep were monitored by aerosol sample probes and mass balance measurements. 23 refs., 22 figs., 3 tabs

  10. The possibility of using materials based on secondary gravel in civil construction

    Galitskova Yulia

    2017-01-01

    Full Text Available By now, the wear and tear of housing stock is more than 50%. Each year the number of old and dilapidated housing is growing, but it is gradually replaced by modern buildings. However, wastes accumulated from dismantling of buildings and constructions, are underutilized and, usually are just stored at landfills, or used for temporary roads construction. The purpose of this research is to define construction wastes characteristics and to explore possibilities for recycling of wastes from construction materials production. The paper also analyzes housing stock condition and basic requirements to building materials used in construction; and demonstrates results building materials based on secondary gravel investigation. While working with materials based on waste requirements the authors conducted laboratory research. Thus, the paper presents the analysis of laboratory tests results that made it possible to draw conclusions about the possible use of building materials based on secondary gravel and about their conformity to specified requirements. The researchers also developed proposals and recommendations to improve the competitiveness of such materials.

  11. Application of ELJ to create and maintain side channels in a dynamic gravel bed river

    Crabbe, E.; Crowe Curran, J.; Ockelford, A.

    2017-12-01

    Braided and anastomosing rivers create and maintain a large amount of side channel habitat. Unfortunately, many rivers that were once multi-channel rivers have been constrained to single thread channels as a consequence of land use changes that occurred in the 19th and 20th centuries or earlier. An increasingly common management goal today is the re-creation of self-maintaining side and tributary habitat through as natural means as possible. This work examines the geomorphic history of one such channel and the success of recent rehabilitation efforts. Our case study comes from the South Fork Nooksack River in the Cascades Range in Washington State. The Nooksack River is a gravel and sand bed channel with a snowmelt dominated hydrograph. Engineered log jams (ELJ) have been employed to direct flow into side and chute channels with the larger goals of increasing overall channel complexity and salmon spawning opportunities. ELJs have been constructed on the channel since the 2000s, and the ELJs in the study reaches range in age up to 10 years. The size and design of individual jams within the reach vary, enabling a comparison between jam types. ELJs are evaluated for their ability to maintain gravel bar locations and open tributary channels through the snowmelt season over the reach scale. Additional goals of trapping wood onto the jams and existing bars, stabilizing channel banks, and allowing for the growth of bar vegetation are also examined.

  12. Transnational Crime Fictions and Argentina's Criminal State

    Caballero, Juan

    2013-01-01

    My dissertation, titled "Transnational Crime Fictions and Argentina's Criminal State," proposes a new understanding of the dictatorship novels of Ricardo Piglia, Juan José Saer, and Manuel Puig grounded in their shared appropriation from popular crime fiction. Across the 1940's, 50's, and 60's, a wide range of popular crime fiction was translated, written, theorized, printed and reprinted in Argentina, and these popular genres grew steadily in readership, visibility, and cultural legitimacy....

  13. Update on women in physics in Argentina

    Brudny, Vera; Lagorio, Cecilia; Frechero, Marisa; Tamarit, Francisco

    2013-03-01

    Data collected 10 years ago in Argentina concluded that women in physics were underrepresented in many instances and that a "crystal ceiling" was firmly in place. We have collected updated data for several indicators and compared them with those obtained 10 years ago. Although there is not a clear conclusion to be drawn from this comparison, we try to explain the results within the framework of the changes in scientific policies in Argentina.

  14. Update on women in physics in Argentina

    Brudny, Vera Leonor; Lagorio, Cecilia; Frechero, Marisa Alejandra; Tamarit, Francisco

    2016-01-01

    Data collected 10 years ago in Argentina concluded that women in physics were underrepresented in many instances and that a “crystal ceiling” was firmly in place. We have collected updated data for several indicators and compared them with those obtained 10 years ago. Although there is not a clear conclusion to be drawn from this comparison, we try to explain the results within the framework of the changes in scientific policies in Argentina. Fil: Brudny, Vera Leonor. Universidad de Buenos...

  15. China, Argentina agree to further strategic ties

    2011-01-01

    According to Xinhua,China and Argentina have agreed to further enhance mutual trust and their strategic partnership as the two emerging economies are playing an increasingly important role in the world arena.“China will work with Argentina to strengthen strategic mutual trust,expand cooperation and coordination within multilateral frameworks in order to promote bilateral ties and benefit the two peoples,” Vice President Xi Jinping told Argentine Foreign Minister Hector Timerman on September 9.

  16. Poverty and Health in Argentina

    Maria Alejandra Silva

    2009-06-01

    Full Text Available This article examines health conditions in the rural areas of Central Argentina, the country’s main region for soy-bean production and export. Health conditions are analyzed through the concepts of emerging and re-emerging diseases in a context of increasing poverty. Data on poverty and health was obtained from both primary sources (trade union, government officials, rural doctors and the South Watch/FA/FODEPAL/UNR working group and secondary sources (IPEC/INDEC, IDESA, Consultora Equis, the Argentine Ministry of Employment, ILO, the Ministry of Health, the Ministry of the Environment, toxicology centers and rural doctors. Analysis of rural health conditions gives cause for concern. There is evidence of deterioration in the social determinants of health such as an increase in rural and urban poverty associated with informal employment and child labor. At the same time lack of government epidemiological and toxicological data appears to hide or distort the reality of health conditions.

  17. An Energy Overview of Argentina

    2003-01-01

    The DOE Office of Fossil Energy is maintaining a web site that is meant to provide useful business- and energy-related information about countries and regions of the world for exporters, project developers, and researchers. The site consists of more than 130 country pages (organized into seven different world regions), with each country page having its own set of links to information sources about that country. There are also more than 30 Country Energy Overviews at the web site -- each of these is a comprehensive review of a specific country's entire energy situation, including sections on Energy Policy, Oil, Natural Gas, Coal, Hydroelectric/Renewables, Nuclear Power, Energy Transmission Infrastructure, Electricity, Electric Industry Overview, Environmental Activities, Privatization, Trade, and Economic Situation. The specific country highlighted in this Country Energy Overview is Argentina. The site is designed to be dynamic. Updates to the overviews will be made as need and resources permit

  18. Nuclear security standard: Argentina approach

    Bonet Duran, Stella M.; Rodriguez, Carlos E.; Menossi, Sergio A.; Serdeiro, Nelida H.

    2007-01-01

    Argentina has a comprehensive regulatory system designed to assure the security and safety of radioactive sources, which has been in place for more than fifty years. In 1989 the Radiation Protection and Nuclear Safety branch of the National Atomic Energy Commission created the 'Council of Physical Protection of Nuclear Materials and Installations' (CAPFMIN). This Council published in 1992 a Physical Protection Standard based on a deep and careful analysis of INFCIRC 225/Rev.2 including topics like 'sabotage scenario'. Since then, the world's scenario has changed, and some concepts like 'design basis threat', 'detection, delay and response', 'performance approach and prescriptive approach', have been applied to the design of physical protection systems in facilities other than nuclear installations. In Argentina, radioactive sources are widely used in medical and industrial applications with more than 1,600 facilities controlled by the Nuclear Regulatory Authority (in spanish ARN). During 2005, measures like 'access control', 'timely detection of intruder', 'background checks', and 'security plan', were required by ARN for implementation in facilities with radioactive sources. To 'close the cycle' the next step is to produce a regulatory standard based on the operational experience acquired during 2005. ARN has developed a set of criteria for including them in a new standard on security of radioactive materials. Besides, a specific Regulatory Guide is being prepared to help licensees of facilities in design a security system and to fulfill the 'Design of Security System Questionnaire'. The present paper describes the proposed Standard on Security of Radioactive Sources and the draft of the Nuclear Security Regulatory Guidance, based on our regulatory experience and the latest international recommendations. (author)

  19. Argentina

    Guillermina Fernández Zambón

    2005-01-01

    Full Text Available La actividad industrial, de cualquier época, tiene una gran importancia para el hombre, pues al igual que el resto de los procesos económicos, es el reflejo del accionar cotidiano de la sociedad sobre el espacio. Considerando esto, el presente articulo tiene como objetivo presentar al patrimonio industrial como recurso para organizar rutas turísticas que permitan en algunos casos recuperar espacios industriales abandonados o usar establecimientos industriales en funcionamiento pero que pueden incorporarse a este tipo de desarrollo turístico. La creación de rutas turísticas puede permitir la reactivación de las economías locales, por constituirse en definitiva en una nueva actividad económica. Para lograr esto es necesario articular el sector público y el privado. De esta forma es posible, a través de la creación de rutas turísticas del patrimonio industrial, generar un desarrollo turístico local sustentable.

  20. Optimizing the use of natural gravel Brantas river as normal concrete mixed with quality fc = 19.3 Mpa

    Limantara, A. D.; Widodo, A.; Winarto, S.; Krisnawati, L. D.; Mudjanarko, S. W.

    2018-04-01

    The use of natural gravel (rivers) as concrete mixtures is rarely encountered after days of demands for a higher strength of concrete. Moreover, today people have found High-Performance Concrete which, when viewed from the rough aggregate consisted mostly of broken stone, although the fine grain material still used natural sand. Is it possible that a mixture of concrete using natural gravel as a coarse aggregate is capable of producing concrete with compressive strength equivalent to a concrete mixture using crushed stone? To obtain information on this, a series of tests on concrete mixes with crude aggregates of Kalitelu Crusher, Gondang, Tulungagung and natural stone (river gravel) from the Brantas River, Ngujang, Tulungagung in the Materials Testing Laboratory Tugu Dam Construction Project, Kab. Trenggalek. From concrete strength test results using coarse material obtained value 19.47 Mpa, while the compressive strength of concrete with a mixture of crushed stone obtained the value of 21.12 Mpa.

  1. Mining with communities

    Veiga, Marcello M.; Scoble, Malcolm; McAllister, Mary Louise

    2001-01-01

    To be considered as sustainable, a mining community needs to adhere to the principles of ecological sustainability, economic vitality and social equity. These principles apply over a long time span, covering both the life of the mine and post-mining closure. The legacy left by a mine to the community after its closure is emerging as a significant aspect of its planning. Progress towards sustainability is made when value is added to a community with respect to these principles by the mining operation during its life cycle. This article presents a series of cases to demonstrate the diverse potential challenges to achieving a sustainable mining community. These case studies of both new and old mining communities are drawn mainly from Canada and from locations abroad where Canadian companies are now building mines. The article concludes by considering various approaches that can foster sustainable mining communities and the role of community consultation and capacity building. (author)

  2. Deposition of Suspended Clay to Open and Sand-Filled Framework Gravel Beds in a Laboratory Flume

    Mooneyham, Christian; Strom, Kyle

    2018-01-01

    Pulses of fine sediment composed of sand, silt, and clay can be introduced to gravel bed rivers through runoff from burn-impacted hillslopes, landslides, bank failure, or the introduction of reservoir sediment as a result of sluicing or dam decommissioning. Here we present a study aimed at quantifying exchange between suspensions of clay and gravel beds. The questions that motivate the work are: how do bed roughness and pore space characteristics, shear velocity (u∗), and initial concentration (C0) affect clay deposition on or within gravel beds? Where does deposition within these beds occur, and can deposited clay be resuspended while the gravel is immobile? We examine these questions in a laboratory flume using acrylic, open-framework gravel, and armored sand-gravel beds under conditions of varying u∗ and C0. Deposition of clay occurred to all beds (even with Rouse numbers ˜ 0.01). We attribute deposition under full suspension conditions to be an outcome of localized protected zones where clay can settle and available pore space in the bed. For smooth wall cases, protection came from the viscous wall region and the development of bed forms; for the rough beds, protection came from separation zones and low-velocity pore spaces. Bed porosity was the strongest influencer of nondimensional deposition rate; deposition increased with porosity. Deposition was inversely related to u∗ for the acrylic bed runs; no influence of u∗ was found for the porous bed runs. Increases in discharge resulted in resuspension of clay from acrylic beds; no resuspension was observed in the porous bed runs.

  3. McGET: A rapid image-based method to determine the morphological characteristics of gravels on the Gobi desert surface

    Mu, Yue; Wang, Feng; Zheng, Bangyou; Guo, Wei; Feng, Yiming

    2018-03-01

    The relationship between morphological characteristics (e.g. gravel size, coverage, angularity and orientation) and local geomorphic features (e.g. slope gradient and aspect) of desert has been used to explore the evolution process of Gobi desert. Conventional quantification methods are time-consuming, inefficient and even prove impossible to determine the characteristics of large numbers of gravels. We propose a rapid image-based method to obtain the morphological characteristics of gravels on the Gobi desert surface, which is called the "morphological characteristics gained effectively technique" (McGET). The image of the Gobi desert surface was classified into gravel clusters and background by a machine-learning "classification and regression tree" (CART) algorithm. Then gravel clusters were segmented into individual gravel clasts by separating objects in images using a "watershed segmentation" algorithm. Thirdly, gravel coverage, diameter, aspect ratio and orientation were calculated based on the basic principles of 2D computer graphics. We validated this method with two independent datasets in which the gravel morphological characteristics were obtained from 2728 gravels measured in the field and 7422 gravels measured by manual digitization. Finally, we applied McGET to derive the spatial variation of gravel morphology on the Gobi desert along an alluvial-proluvial fan located in Hami, Xinjiang, China. The validated results show that the mean gravel diameter measured in the field agreed well with that calculated by McGET for large gravels (R2 = 0.89, P < 0.001). Compared to manual digitization, the McGET accuracies for gravel coverage, gravel diameter and aspect ratio were 97%, 83% and 96%, respectively. The orientation distributions calculated were consistent across two different methods. More importantly, McGET significantly shortens the time cost in obtaining gravel morphological characteristics in the field and laboratory. The spatial variation results

  4. Radon exposure in abandoned metalliferous mines of South America

    Silva, A.A.R. da; Umisedo, N.; Yoshimura, E.M.; Anjos, R.M.; Valladares, D.L.; Velasco, H.; Rizzotto, M.

    2011-01-01

    Since the days of the Spanish and Portuguese conquerors, South America has been closely associated with the metalliferous ore mining. Gold, silver, tin, lead, tungsten, nickel, copper, and palladium ores have been explored over the last centuries. In addition, there has also been the development and promotion of other economic activities related to mining, as the underground mine tourism. A few works have been published on radon levels in the South American mining. In this study, we investigated the radon transport process and its health hazard in two exhausted and abandoned mines in San Luis Province, Argentina. These mines were chosen because they have different physical configurations in their cavities, features which can affect the air flow patterns and radon concentrations. La Carolina gold mine (32 deg 48' 0'' S, 66 deg 60' 0'' W) is currently a blind end system, corresponding to a horizontal excavation into the side of a mountain, with only a main adit. Los Condores wolfram mine (32 deg 33' 25'' S, 65 deg 15' 20'' W) is also a horizontal excavation into the side of a mountain, but has a vertical output (a shaft) at the end of the main gallery. Three different experimental methodologies were used. Radon concentration measurements were performed by CR-39 nuclear track detectors. The distribution of natural radionuclide activities ( 40 K, 232 Th and 238 U) was determined from rock samples collected along their main adits, using in laboratory gamma-ray spectrometry. The external gamma dose rate was evaluated using thermoluminescent dosimeters and a portable survey meter. The values for the 222 Rn concentration ranged from 0.43 ± 0.04 to 1.48 ± 0.12 kBq/m 3 in the Los Condores wolfram mine and from 1.8 ± 0.1 to 6.0±0.5 kBq/m 3 in the La Carolina gold mine, indicating that, in this mine, the radon levels exceed up to four times the action level of 1.5 kBq/m 3 recommended by the ICRP. The patterns of the radon transport process revealed that the La Carolina

  5. Wetland and waterbody restoration and creation associated with mining

    Brooks, R.P.

    1990-01-01

    Published and unpublished reports are reviewed and the strategies and techniques used to facilitate the establishment of wetlands and waterbodies during mine reclamation are summarized. Although the emphasis is on coal, phosphate, and sand and gravel operations, the methods are relevant to other types of mining and mitigation activities. The following key points should receive attention during planning and mitigation processes: (1) development of site-specific objectives that are related to regional wetland trends; (2) integration of wetland mitigation plans with mining operations and reclamation at the beginning of any project; (3) wetland designs that mimic natural systems and provide flexibility for unforeseen events; (4) assurance that basin morphometry and control of the hydrologic regime are properly addressed before considering other aspects of a project; and (5) identification of mandatory monitoring as a known cost. Well-designed studies that use comparative approaches are needed to increase the database on wetland restoration technology. Meanwhile, regional success criteria for different classes of wetlands need to be developed by consensus agreement among professionals. The rationale for a particular mitigation strategy must have a sound, scientific basis if the needs of mining industries are to be balanced against the necessity of wetland operation. 93 refs., 3 figs

  6. South African mine valuation

    Storrar, C D

    1977-01-01

    This article sets out the basic concepts of mine valuation, with gold mining receiving more space than base minerals and coal. Sampling practice is given special attention. Chapter headings are methods of investigation, sampling, underground sampling, averaging of underground sampling, diamond-drill sampling, mass and mineral content of ore, organization of a sample office, working costs, mining pay limits, ore reserves, ore accounting, maintenance of grade, forecasting operations and life of mine, statistical mine valuation, state's share of profits and taxation, and financial valuation of mining ventures.

  7. Technological highwall mining

    Davison, I. [Highwall Systems (United States)

    2006-09-15

    The paper explores the issues facing highwall mining. Based in Chilhowie, Virginia, American Highwall Systems has developed a highwall mining system that will allow the mining of coal seams from 26 in to 10 ft in thickness. The first production model, AH51, began mining in August 2006. Technologies incorporated into the company's mining machines to improve the performance, enhance the efficiency, and improve the reliability of the highwall mining equipment incorporate technologies from many disciplines. Technology as applied to design engineering, manufacturing and fabrication engineering, control and monitoring computer hardware and software has played an important role in the evolution of the American Highwall Systems design concept. 5 photos.

  8. Numerical simulation of the free surface and water inflow of a slope, considering the nonlinear flow properties of gravel layers: a case study

    Yang, Bin; Yang, Tianhong; Xu, Zenghe; Liu, Honglei; Shi, Wenhao; Yang, Xin

    2018-02-01

    Groundwater is an important factor of slope stability, and 90% of slope failures are related to the influence of groundwater. In the past, free surface calculations and the prediction of water inflow were based on Darcy's law. However, Darcy's law for steady fluid flow is a special case of non-Darcy flow, and many types of non-Darcy flows occur in practical engineering applications. In this paper, based on the experimental results of laboratory water seepage tests, the seepage state of each soil layer in the open-pit slope of the Yanshan Iron Mine, China, were determined, and the seepage parameters were obtained. The seepage behaviour in the silt layer, fine sand layer, silty clay layer and gravelly clay layer followed the traditional Darcy law, while the gravel layers showed clear nonlinear characteristics. The permeability increases exponentially and the non-Darcy coefficient decreases exponentially with an increase in porosity, and the relation among the permeability, the porosity and the non-Darcy coefficient is investigated. A coupled mathematical model is established for two flow fields, on the basis of Darcy flow in the low-permeability layers and Forchheimer flow in the high-permeability layers. In addition, the effect of the seepage in the slope on the transition from Darcy flow to Forchheimer flow was considered. Then, a numerical simulation was conducted by using finite-element software (FELAC 2.2). The results indicate that the free surface calculated by the Darcy-Forchheimer model is in good agreement with the in situ measurements; however, there is an evident deviation of the simulation results from the measured data when the Darcy model is used. Through a parameter sensitivity analysis of the gravel layers, it can be found that the height of the overflow point and the water inflow calculated by the Darcy-Forchheimer model are consistently less than those of the Darcy model, and the discrepancy between these two models increases as the permeability

  9. The influence of sediment transport rate on the development of structure in gravel bed rivers

    Ockelford, Annie; Rice, Steve; Powell, Mark; Reid, Ian; Nguyen, Thao; Tate, Nick; Wood, Jo

    2013-04-01

    Although adjustments of surface grain size are known to be strongly influenced by sediment transport rate little work has systematically explored how different transport rates can affect the development of surface structure in gravel bed rivers. Specifically, it has been well established that the transport of mixed sized sediments leads to the development of a coarser surface or armour layer which occurs over larger areas of the gravel bed. Armour layer development is known to moderate overall sediment transport rate as well as being extremely sensitive to changes in applied shear stress. However, during this armouring process a bed is created where, smaller gain scale changes, to the bed surface are also apparent such as the development of pebble clusters and imbricate structures. Although these smaller scale changes affect the overall surface grain size distribution very little their presence has the ability to significantly increase the surface stability and hence alter overall sediment transport rates. Consequently, the interplay between the moderation of transport rate as a function of surface coarsening at a larger scale and moderation of transport rate as a function of the development of structure on the bed surface at the smaller scale is complicated and warrants further investigation. During experiments a unimodal grain size distribution (σg = 1.30, D50 = 8.8mm) was exposed to 3 different levels of constant discharge that produced sediment transport conditions ranging from marginal transport to conditions approaching full mobility of all size fractions. Sediment was re-circulated during the experiments surface grain size distribution bed load and fractional transport rates were measured at a high temporal resolution such that the time evolution of the beds could be fully described. Discussion concentrates on analysing the effects of the evolving bed condition sediment transport rate (capacity) and transported grain size (competence). The outcome of this

  10. 32 CFR 644.505 - Disposal plan for embedded gravel, sand or stone.

    2010-07-01

    ... or level to which the material may be removed, and any restoration of the site after removal. (d... familiar with the material involved and the operations for mining, quarrying or otherwise removing it...

  11. Contract Mining versus Owner Mining – The Way Forward | Suglo ...

    Ghana Mining Journal ... By contracting out one or more of their mining operations, the mining companies can concentrate on their core businesses. This paper reviews ... The general trends in the mining industry show that contract mining will be the way forward for most mines under various circumstances in the future.

  12. Optimization of mining design of Hongwei uranium mine

    Wu Sanmao; Yuan Baixiang

    2012-01-01

    Combined with the mining conditions of Hongwei uranium mine, optimization schemes for hoisting cage, mine drainge,ore transport, mine wastewater treatment, power-supply system,etc are put forward in the mining design of the mine. Optimized effects are analyzed from the aspects of technique, economy, and energy saving and reducing emissions. (authors)

  13. Uranium evaluation and mining techniques

    1980-01-01

    Full text: Report on an IAEA/NEA/IANEC international symposium, Buenos Aires, Argentina, 1-5 October 1979. The symposium was attended by 162 participants from 35 countries and five international organizations, with 35 observers also registered. Twenty-nine papers and two informal discussions were presented in seven sessions. Planning nuclear power programmes is fraught with a very wide range of uncertainties, some of which are the uncertainties associated with rising costs and ever-lengthening lead times, the uncertainties of the rate of growth of nuclear energy, the uncertainties caused by anti-nuclear activities, and the uncertainties of uranium resources and availability of uranium supplies. Present known resources, not all of which may actually become uranium supply before the year 2025, are slightly less than 5 million tonnes uranium. Even if all these resources could be produced, production rates from them would drop seriously in the mid-1990s. It is, therefore, most important that the uncertainty of uranium resources and availability of supply be dealt with promptly. In this respect many countries of the world have begun national programmes either to determine their uranium potential, or to explore for uranium deposits. The symposium held in Buenos Aires at the invitation of the Government of Argentina sought to provide these countries with a state-of-the-art report on the various methods of uranium resource evaluation. Developments and improvements in both new and old techniques of mineral assessment proliferate. Notable among the 'newer' methods are geostatistical estimation of ore reserves, a sophisticated method which, although still under development, has gained wide recognition. In the domain of objective measurements and sample-based estimation procedures, the older classical methods also yield acceptable estimates when properly used. But uranium ore reserves are always inadequate for long-range planning, seldom exceeding a few years' demand. An

  14. Control of nuclear materials and materials in Argentina

    Arbor G, A.; Fernandes M, S.

    1988-01-01

    A general view about the safeguards activities in Argentina is presented. The national system of accounting for and control of nuclear materials is described. The safeguards agreement signed by Argentina are presented. (E.G.) [pt

  15. Reuse of mining dams waste for the processing of interlocking blocks for paving

    Machado, Raissa Ribeiro Lima; Ribeiro, Guilherme Borges; Silva, Sidney Nicodemos da

    2014-01-01

    The environmental impact of mining dam residues can be mitigated by their reuse in the production of interlocking blocks for pavements with a mechanical strength greater than 50 MPa. From the mixture of cement CPV-ARI, sand and gravel, the characterization of the mechanical and physicochemical properties was performed by the following procedures: SEM, FRX, XRD, compression tests and thermal analysis (DSC). These blocks produced from these residues can be considered an economical alternative for the mining depletion cycle in the State of Minas Gerais. This work sought to improve the traces with the replacement the sand of the rivers bed by residues of mining dams that can represent an opportunity for generation of employment and income

  16. Uranium mining in Australia

    Anon.

    1980-01-01

    Known uranium deposits and the companies involved in uranium mining and exploration in Australia are listed. The status of the development of the deposits is outlined and reasons for delays to mining are given

  17. Mines and Mineral Resources

    Department of Homeland Security — Mines in the United States According to the Homeland Security Infrastructure Program Tiger Team Report Table E-2.V.1 Sub-Layer Geographic Names, a mine is defined as...

  18. Performance of a half-saturated vertical flow wetland packed with volcanic gravel in stormwater treatment.

    Chen, Yaoping; Park, Kisoo; Niu, Siping; Kim, Youngchul

    2014-01-01

    A half-saturated pilot-scale wetland planted with Acorus calamus was built to treat urban stormwater. The design comprises a sedimentation tank for pretreatment, and a vertical flow volcanic gravel wetland bed equipped with a recirculation device. Eighteen rainfall events were monitored in 2012. The treatment system achieved total removal efficiencies of 99.4, 81, 50, and 86% for suspended solids, organic matter, nitrogen and phosphorus, respectively, and 29, 68, and 25% for copper, zinc, and lead, respectively, at a 3-day hydraulic residence time. In the wetland bed, the removal of ammonia, total nitrogen, and zinc were improved by recirculation. Plant uptake provided 18% of nitrogen removal and 39% of phosphorus removal. During the experimental stage, only 1.4% of the pore volume in substrate was reduced due to clogging, implying that the wetland can operate without clogging for a relatively long period.

  19. Sampling surface and subsurface particle-size distributions in wadable gravel-and cobble-bed streams for analyses in sediment transport, hydraulics, and streambed monitoring

    Kristin Bunte; Steven R. Abt

    2001-01-01

    This document provides guidance for sampling surface and subsurface sediment from wadable gravel-and cobble-bed streams. After a short introduction to streams types and classifications in gravel-bed rivers, the document explains the field and laboratory measurement of particle sizes and the statistical analysis of particle-size distributions. Analysis of particle...

  20. Mining Views : database views for data mining

    Blockeel, H.; Calders, T.; Fromont, É.; Goethals, B.; Prado, A.

    2008-01-01

    We present a system towards the integration of data mining into relational databases. To this end, a relational database model is proposed, based on the so called virtual mining views. We show that several types of patterns and models over the data, such as itemsets, association rules and decision

  1. Mining Views : database views for data mining

    Blockeel, H.; Calders, T.; Fromont, É.; Goethals, B.; Prado, A.; Nijssen, S.; De Raedt, L.

    2007-01-01

    We propose a relational database model towards the integration of data mining into relational database systems, based on the so called virtual mining views. We show that several types of patterns and models over the data, such as itemsets, association rules, decision trees and clusterings, can be

  2. Unintended consequences of restoration: loss of riffles and gravel substrates following weir installation.

    Salant, Nira L; Schmidt, John C; Budy, Phaedra; Wilcock, Peter R

    2012-10-30

    We used pre- and post-restoration channel surveys of the Donner und Blitzen River, Oregon, to evaluate the effects of grade-control structures on channel morphology and baseflow habitat conditions for native redband trout and other aquatic biota. Six years after installation, we found that the channel had a smaller proportion of riffles and pools and less gravel substrate, combined with an increase in the proportion of flat waters and consolidated clay on the bed surface. Both local scour downstream from weirs and backwater effects upstream from weirs appear to have caused the general flattening and fining of the channel. A direct-step backwater calculation indicates that backwaters extended to the upstream weir at both low and high flows, creating long sections of flat water separated by short, steep drops. Despite backwater effects, a comparison of longitudinal profiles before and six years after weir installation showed bed erosion downstream of nearly all weirs, likely a consequence of the cohesive clay material that dominates the channel bed and banks. A deep inner channel reflects the cohesive nature of the clay and the mechanisms of abrasion, and indicates that sediment load is low relative to the transport capacity of the flow. Unfortunately, weirs were problematic in this system because of the cohesive clay substrate, limited sediment supply, and low channel gradient. Although deeper flows due to backwaters might be more favorable for resident trout, less gravel and fewer riffles are likely to negatively impact trout spawning habitat, macroinvertebrate communities, and biofilm productivity. Our results demonstrate the potential limitations of a single-feature approach to restoration that may be ineffective for a given geomorphic context and may overlook other aspects of the ecosystem. We highlight the need to incorporate geomorphic characteristics of a system into project design and predictions of system response. Copyright © 2012 Elsevier Ltd. All rights

  3. Temporal and spatial variability in thalweg profiles of a gravel-bed river

    Madej, Mary Ann

    1999-01-01

    This study used successive longitudinal thalweg profiles in gravel-bed rivers to monitor changes in bed topography following floods and associated large sediment inputs. Variations in channel bed elevations, distributions of residual water depths, percentage of channel length occupied by riffles, and a spatial autocorrelation coefficient (Moran's I) were used to quantify changes in morphological diversity and spatial structure in Redwood Creek basin, northwestern California. Bed topography in Redwood Creek and its major tributaries consists primarily of a series of pools and riffles. The size, frequency and spatial distribution of the pools and riffles have changed significantly during the past 20 years. Following large floods and high sediment input in Redwood Creek and its tributaries in 1975, variation in channel bed elevations was low and the percentage of the channel length occupied by riffles was high. Over the next 20 years, variation in bed elevations increased while the length of channel occupied by riffles decreased. An index [(standard deviation of residual water depth/bankfull depth) × 100] was developed to compare variations in bed elevation over a range of stream sizes, with a higher index being indicative of greater morphological diversity. Spatial autocorrelation in the bed elevation data was apparent at both fine and coarse scales in many of the thalweg profiles and the observed spatial pattern of bed elevations was found to be related to the dominant channel material and the time since disturbance. River reaches in which forced pools dominated, and in which large woody debris and bed particles could not be easily mobilized, exhibited a random distribution of bed elevations. In contrast, in reaches where alternate bars dominated, and both wood and gravel were readily transported, regularly spaced bed topography developed at a spacing that increased with time since disturbance. This pattern of regularly spaced bed features was reversed

  4. Comparison of Machine Learning methods for incipient motion in gravel bed rivers

    Valyrakis, Manousos

    2013-04-01

    Soil erosion and sediment transport of natural gravel bed streams are important processes which affect both the morphology as well as the ecology of earth's surface. For gravel bed rivers at near incipient flow conditions, particle entrainment dynamics are highly intermittent. This contribution reviews the use of modern Machine Learning (ML) methods implemented for short term prediction of entrainment instances of individual grains exposed in fully developed near boundary turbulent flows. Results obtained by network architectures of variable complexity based on two different ML methods namely the Artificial Neural Network (ANN) and the Adaptive Neuro-Fuzzy Inference System (ANFIS) are compared in terms of different error and performance indices, computational efficiency and complexity as well as predictive accuracy and forecast ability. Different model architectures are trained and tested with experimental time series obtained from mobile particle flume experiments. The experimental setup consists of a Laser Doppler Velocimeter (LDV) and a laser optics system, which acquire data for the instantaneous flow and particle response respectively, synchronously. The first is used to record the flow velocity components directly upstream of the test particle, while the later tracks the particle's displacements. The lengthy experimental data sets (millions of data points) are split into the training and validation subsets used to perform the corresponding learning and testing of the models. It is demonstrated that the ANFIS hybrid model, which is based on neural learning and fuzzy inference principles, better predicts the critical flow conditions above which sediment transport is initiated. In addition, it is illustrated that empirical knowledge can be extracted, validating the theoretical assumption that particle ejections occur due to energetic turbulent flow events. Such a tool may find application in management and regulation of stream flows downstream of dams for stream

  5. Uranium mine ventilation

    Katam, K.; Sudarsono

    1982-01-01

    Uranium mine ventilation system aimed basically to control and decreasing the air radioactivity in mine caused by the radon emanating from uranium ore. The control and decreasing the air ''age'' in mine, with adding the air consumption volume, increasing the air rate consumption, closing the mine-out area; using closed drainage system. Air consumption should be 60m 3 /minute for each 9m 2 uranium ore surfaces with ventilation rate of 15m/minute. (author)

  6. MONITORING OF MINING

    Berislav Šebečić

    1996-12-01

    Full Text Available The way mining was monitored in the past depended on knowledge, interest and the existing legal regulations. Documentary evidence about this work can be found in archives, libraries and museums. In particular, there is the rich archival material (papers and books concerning the work of the one-time Imperial and Royal Mining Captaincies in Zagreb, Zadar, Klagenfurt and Split, A minor part of the documentation has not yet been transferred to Croatia. From mining handbooks and books we can also find out about mining in Croatia. In the context of Austro-Hungary. For example, we can find out that the first governorships in Zagreb and Zadar headed the Ban, Count Jelacic and Baron Mamula were also the top mining authorities, though this, probably from political motives, was suppressed in the guides and inventories or the Mining Captaincies. At the end of the 1850s, Croatia produced 92-94% of sea salt, up to 8.5% of sulphur, 19.5% of asphalt and 100% of oil for the Austro-Hungarian empire. From data about mining in the Split Mining Captaincy, prepared for the Philadephia Exhibition, it can be seen that in the exploratory mining operations in which there were 33,372 independent mines declared in 1925 they were looking mainly for bauxite (60,0%, then dark coal (19,0%, asphalts (10.3% and lignites (62%. In 1931, within the area covered by the same captaincy, of 74 declared mines, only 9 were working. There were five coal mines, three bauxite mines and one for asphalt. I suggest that within state institution, the Mining Captaincy or Authority be renewed, or that a Mining and Geological Authority be set ap, which would lead to the more complete affirmation of Croatian mining (the paper is published in Croatian.

  7. Mine drainage treatment

    Golomeova, Mirjana; Zendelska, Afrodita; Krstev, Boris; Golomeov, Blagoj; Krstev, Aleksandar

    2012-01-01

    Water flowing from underground and surface mines and contains high concentrations of dissolved metals is called mine drainage. Mine drainage can be categorized into several basic types by their alkalinity or acidity. Sulfide rich and carbonate poor materials are expected to produce acidic drainage, and alkaline rich materials, even with significant sulfide concentrations, often produce net alkaline water. Mine drainages are dangerous because pollutants may decompose in the environment. In...

  8. Mining in El Salvador

    Pacheco Cueva, Vladimir

    2014-01-01

    In this guest article, Vladimir Pacheco, a social scientist who has worked on mining and human rights shares his perspectives on a current campaign against mining in El Salvador – Central America’s smallest but most densely populated country.......In this guest article, Vladimir Pacheco, a social scientist who has worked on mining and human rights shares his perspectives on a current campaign against mining in El Salvador – Central America’s smallest but most densely populated country....

  9. The mining methods at the Fraisse mine

    Heurley, P.; Vervialle, J.P.

    1985-01-01

    The Fraisse mine is one of the four underground mines of the La Crouzille mining divisions of Cogema. Faced with the necessity to mechanize its workings, this mine also had to satisfy a certain number of stringent demands. This has led to concept of four different mining methods for the four workings at present in active operation at this pit, which nevertheless preserve the basic ideas of the methods of top slicing under concrete slabs (TSS) or horizontal cut-and-fill stopes (CFS). An electric scooptram is utilized. With this type of vehicle the stringent demands for the introduction of means for fire fighting and prevention are reduced to a minimum. Finally, the dimensions of the vehicles and the operation of these methods result in a net-to-gross tonnages of close to 1, i.e. a maximum output, combined with a minimum of contamination [fr

  10. Data Mining for CRM

    Thearling, Kurt

    Data Mining technology allows marketing organizations to better understand their customers and respond to their needs. This chapter describes how Data Mining can be combined with customer relationship management to help drive improved interactions with customers. An example showing how to use Data Mining to drive customer acquisition activities is presented.

  11. Colombian mining legislation

    Mendoza Delgado, Eva Isolina

    2004-01-01

    The paper makes a historical recount of the mining legislation in Colombia, it is about the more relevant aspects of the Code of Mines, like they are the title miner, obligations, economic aspects, integration of mining areas and of the benefits contemplated in the law 685 of 2001

  12. Mine waste management

    Hutchinson, I.P.G.; Ellison, R.D.

    1992-01-01

    This book reports on mine waste management. Topics covered include: Performance review of modern mine waste management units; Mine waste management requirements; Prediction of acid generation potential; Attenuation of chemical constituents; Climatic considerations; Liner system design; Closure requirements; Heap leaching; Ground water monitoring; and Economic impact evaluation

  13. Mining compressing sequential problems

    Hoang, T.L.; Mörchen, F.; Fradkin, D.; Calders, T.G.K.

    2012-01-01

    Compression based pattern mining has been successfully applied to many data mining tasks. We propose an approach based on the minimum description length principle to extract sequential patterns that compress a database of sequences well. We show that mining compressing patterns is NP-Hard and

  14. Mine water treatment

    Komissarov, S V

    1980-10-01

    This article discusses composition of chemical compounds dissolved or suspended in mine waters in various coal basins of the USSR: Moscow basin, Kuzbass, Pechora, Kizelovsk, Karaganda, Donetsk and Chelyabinsk basins. Percentage of suspended materials in water depending on water source (water from water drainage system of dust suppression system) is evaluated. Pollution of mine waters with oils and coli bacteria is also described. Recommendations on construction, capacity of water settling tanks, and methods of mine water treatment are presented. In mines where coal seams 2 m or thicker are mined a system of two settling tanks should be used: in the upper one large grains are settled, in the lower one finer grains. The upper tank should be large enough to store mine water discharged during one month, and the lower one to store water discharged over two months. Salty waters from coal mines mining thin coal seams should be treated in a system of water reservoirs from which water evaporates (if climatic conditions permit). Mine waters from mines with thin coal seams but without high salt content can be treated in a system of long channels with water plants, which increase amount of oxygen in treated water. System of biological treatment of waste waters from mine wash-houses and baths is also described. Influence of temperature, sunshine and season of the year on efficiency of mine water treatment is also assessed. (In Russian)

  15. Mountaintop mining consequences

    M.A. Palmer; E.S. Bernhardt; W.H. Schlesinger; K.N. Eshleman; E. Foufoula-Georgiou; M.S. Hendryx; A.D. Lemly; G.E. Likens; O.L. Loucks; M.E. Power; P.S. White; P.R. Wilcock

    2010-01-01

    There has been a global, 30-year increase in surface mining (1), which is now the dominant driver of land-use change in the central Appalachian ecoregion of the United States (2). One major form of such mining, mountaintop mining with valley fills (MTM/VF) (3), is widespread throughout eastern Kentucky, West Virginia (WV), and southwestern Virginia. Upper elevation...

  16. Ghana Mining Journal: Contact

    Principal Contact. Professor Daniel Mireku-Gyimah Editor-in-Chief University of Mines & Technology Ghana Mining Journal University of Mines & Technology P. O. BOX 237 Tarkwa Ghana Phone: +233 362 20280/20324. Fax: +233 362 20306. Email: dm.gyimah@umat.edu.gh ...

  17. Psychiatry and humanism in Argentina.

    Niño Amieva, Alejandra

    2016-04-01

    The authors of the present selection of Latin American Psychiatry texts were characterized by a common deep humanistic attitude. These prolific writers were able to establish or extend the scope of the discipline in which they chose to act, questioning the establishment of rigid boundaries within the framework of a rigorous epistemological reflection. Thus the systematizing spirit of Jose Ingenieros' in the context of positivist evolutionism, resulted in the act of founding a discipline that integrated the biological and the social. In the case of Guillermo Vidal his conception of mental health went beyond the biomedical to consider psychotherapies as an emotional commitment, continence and empathic understanding; with regard to César Cabral his formation and extensive clinical practice resulted in a work defined by the inquiring into the theoretical concepts underlying Psychiatry and Clinical Psychology. This brief selection does not exhaust the issues or the level of ideas and discussions of Psychiatry in Argentina, but constitutes a textual corpus representative of a disciplinary conception understood as scientific and humanistic endeavor.

  18. Argentina chiama Italia: Friuli risponde

    Silvana Serafin

    2010-03-01

    Full Text Available The study analyzes the migratory waves from Friuli which, from the 1870s up to the post-World War II years, extensively moved towards Argentina, settling in the areas around the cities of Santa Fe, Cordoba, Entre Ríos, Chaco and Buenos Aires, but reaching also regions as far away as Patagonia. The accurate and well diffused net of the Fogolār Furlan, besides its function as friendly society, also provides to the promulgation of ancient traditions and mores among the new generations, transmitting on to them the cultural, linguistic and ethnic memory of the motherland. Epistles, tales, novels and poems form a paideia which is thus constantly being enlivened, eveng among those who assumed Argentinian nationality or were born in the country. Of utmost interest is, therefore, the resulting literary corpus, representing as it does a renewed search for identity in the form of a dialogue with the world, extending itself well beyond the contingency of boundaries and transmitting the universal essence of logos.

  19. Flow structure through pool-riffle sequences and a conceptual model for their sustainability in gravel-bed rivers

    D. Caamano; P. Goodwin; J. M. Buffington

    2010-01-01

    Detailed field measurements and simulations of three-dimensional flow structure were used to develop a conceptual model to explain the sustainability of self-formed pool-riffle sequences in gravel-bed rivers. The analysis was conducted at the Red River Wildlife Management Area in Idaho, USA, and enabled characterization of the flow structure through two consecutive...

  20. Bed stability in unconfined gravel bed mountain streams: With implications for salmon spawning viability in future climates

    Jim McKean; Daniele Tonina

    2013-01-01

    Incubating eggs of autumn-spawning Chinook salmon (Oncorhynchus tshawytscha) could be at risk of midwinter high flows and substrate scour in a changing climate. A high-spatial-resolution multidimensional hydrodynamics model was used to assess the degree of scour risk in low-gradient unconfined gravel bed channels that are the favored environment for autumn-spawning...

  1. Removal of Zn(II) from electroplating effluent using yeast biofilm formed on gravels: batch and column studies

    2014-01-01

    Background Present study deals with the removal of Zn(II) ions from effluent using yeast biofilm formed on gravels. Methods The biofilm forming ability of Candida rugosa and Cryptococcus laurentii was evaluated using XTT (2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide) reduction assay and monitored by scanning electron microscopy (SEM), and Confocal laser scanning microscopy (CLSM). Copious amount of extracellular polymeric substances (EPS) produced by yeast species was quantified and characterized by Fourier transform infrared spectroscopy (FT-IR). Results Yeast biofilm formed on gravels by C. rugosa and C. laurentii showed 88% and 74.2% removal of Zn(II) ions respectively in batch mode. In column mode, removal of Zn(II) ions from real effluent was found to be 95.29% by C. rugosa biofilm formed on gravels. Conclusion The results of the present study showed that there is a scope to develop a cost effective method for the efficient removal of Zn(II) from effluent using gravels coated with yeast biofilm. PMID:24397917

  2. Occurrence, distribution, and volume of metals-contaminated sediment of selected streams draining the Tri-State Mining District, Missouri, Oklahoma, and Kansas, 2011–12

    Smith, D. Charlie

    2016-12-14

    Lead and zinc were mined in the Tri-State Mining District (TSMD) of southwest Missouri, northeast Oklahoma, and southeast Kansas for more than 100 years. The effects of mining on the landscape are still evident, nearly 50 years after the last mine ceased operation. The legacies of mining are the mine waste and discharge of groundwater from underground mines. The mine-waste piles and underground mines are continuous sources of trace metals (primarily lead, zinc, and cadmium) to the streams that drain the TSMD. Many previous studies characterized the horizontal extent of mine-waste contamination in streams but little information exists on the depth of mine-waste contamination in these streams. Characterizing the vertical extent of contamination is difficult because of the large amount of coarse-grained material, ranging from coarse gravel to boulders, within channel sediment. The U.S. Geological Survey, in cooperation with U.S. Fish and Wildlife service, collected channel-sediment samples at depth for subsequent analyses that would allow attainment of the following goals: (1) determination of the relation between concentration and depth for lead, zinc and cadmium in channel sediments and flood-plain sediments, and (2) determination of the volume of gravel-bar sediment from the surface to the maximum depth with concentrations of these metals that exceeded sediment-quality guidelines. For the purpose of this report, volume of gravel-bar sediment is considered to be distributed in two forms, gravel bars and the wetted channel, and this study focused on gravel bars. Concentrations of lead, zinc, and cadmium in samples were compared to the consensus probable effects concentration (CPEC) and Tri-State Mining District specific probable effects concentration (TPEC) sediment-quality guidelines.During the study, more than 700 sediment samples were collected from borings at multiple sites, including gravel bars and flood plains, along Center Creek, Turkey Creek, Shoal Creek

  3. The nuclear research centre at Bariloche, Argentina

    Abriata, J.P.

    2001-01-01

    The nuclear research centre at Bariloche (CAB) is one of the four centres under the Atomic Energy Commission of Argentina (CNEA). The research programme of CAB addresses various issues like nuclear reactor development, nuclear fuel and fuel cycle, applications of radioisotopes and radiation, and waste management. There is also a basic nuclear science component. The human resource development in the areas of physics and nuclear engineering is done in an associated Balseiro Institute which has undergraduate and graduate programmes as well as doctoral and postdoctoral research. The Centre interacts well with the society and provides services in the nuclear area. It has a close interaction with the nuclear sector of Argentina as also with many international organisations. Regulatory control over the Centre is carried out by the Nuclear Regulatory Authority of Argentina. (author)

  4. Mining planing introduction

    Toledo, R.D.

    1985-01-01

    Basic concepts concerning mining parameters, plan establishment and typical procedure methods applied throughout the physical execution of mining operations are here determined, analyzed and discussed. Technological and economic aspects of the exploration phase are presented as well as general mathematical and statistical methods for estimating, analyzing and representing mineral deposits which are virtually essential for good mining project execution. The characterization of important mineral substances and the basic parameters of mining works are emphasized in conjunction with long, medium and short term mining planning. Finally, geological modelling, ore reserves calculations and final economic evaluations are considered using a hypothetical example in order to consolidate the main elaborated ideas. (D.J.M.) [pt

  5. Gold-Mining

    Raaballe, J.; Grundy, B.D.

    2002-01-01

      Based on standard option pricing arguments and assumptions (including no convenience yield and sustainable property rights), we will not observe operating gold mines. We find that asymmetric information on the reserves in the gold mine is a necessary and sufficient condition for the existence...... of operating gold mines. Asymmetric information on the reserves in the mine implies that, at a high enough price of gold, the manager of high type finds the extraction value of the company to be higher than the current market value of the non-operating gold mine. Due to this under valuation the maxim of market...

  6. Improving safety in mining

    NONE

    2007-08-15

    AcuMine is a spin-out company from CRC Mining Australia and the University of Sydney's Australian Centre for Field Robotics (ACFR). Its focus is to provide safety and fatigue management in mining environments. The AcuLine Haul Check system was its first development. Of greater benefit to safety in mines will be the AcuMine Proximity System (APPS) developed to reliably detect and warn drivers when in proximity to other trucks and utility vehicles and to detect personnel near to those heavy vehicles. 6 figs.

  7. Analysis for the siting of a repository in Argentina

    Palacios, E.; Ciallella, N.; Matar, J.; Perucca, J.C.

    1984-02-01

    The first step in the selection of suitable geological formation for disposal of highly radioactive waste in Argentina was to analyse all the country's known occurrences of granite rock, on the basis of bibliographic material. For each occurrence, a determination was made of its petrographic and structural characteristics, the dimensions and specifications of the rock bodies, the seismic and hydrogeological characteristics of the region, its mining and oil-bearing potential, and the demographic, agricultural, cattle-breeding and industrial features of the areas under study. In this way, it was possible to identify something like 200 granite occurrences. In the second stage the following elimination criteria having been applied: (a) bodies located within seismic zones or areas in which mining or oil-drilling operations are carried on; (b) petrographic characteristics of rock indicating significant alterations, such as an advanced state of erosion or decomposition; and (c) bodies located in areas whose hydrogeological characteristics are known to be unfavourable. As a further selection criterion, account was taken of certain unfavourable characteristics from the point of view of the construction and operation of the storage facility. Sites within zones of dense population, tourism or difficult access were considered to be unfavourable. As a result of this second stage, seven formations were identified. A third stage, based on a survey of the preselected granite bodies led to the identificaton of the massifs of La Esperanza and Chasico in Rio Negro province and the Calcatapul and Medio ranges in Chubut province as the most suitable sites for continuing the detailed studies

  8. Data mining in radiology

    Kharat, Amit T; Singh, Amarjit; Kulkarni, Vilas M; Shah, Digish

    2014-01-01

    Data mining facilitates the study of radiology data in various dimensions. It converts large patient image and text datasets into useful information that helps in improving patient care and provides informative reports. Data mining technology analyzes data within the Radiology Information System and Hospital Information System using specialized software which assesses relationships and agreement in available information. By using similar data analysis tools, radiologists can make informed decisions and predict the future outcome of a particular imaging finding. Data, information and knowledge are the components of data mining. Classes, Clusters, Associations, Sequential patterns, Classification, Prediction and Decision tree are the various types of data mining. Data mining has the potential to make delivery of health care affordable and ensure that the best imaging practices are followed. It is a tool for academic research. Data mining is considered to be ethically neutral, however concerns regarding privacy and legality exists which need to be addressed to ensure success of data mining

  9. Argentina's YPF hones in on privatization

    Anon.

    1991-01-01

    This paper reports on Argentina's push to privatize and attract more foreign investment to its petroleum sector which continues to gather momentum. The Argentine government plans by year end 1992 to sell unprofitable assets of Yacimientos Petroliferos Fiscales, then sell as much as 50% of the state oil company through an international stock offering. If privatization proceeds as expected, YPF Pres. Jose Estenssoro the, the company's stock will be offered to private investors early in 1993. The company was founded in 1922. By March 1992, Argentina also will begin selling all assets of state owned Gas del Estado (GDE) through an international bidding process expected to take about 18 months

  10. Communications received from Argentina and Brazil

    1988-05-01

    The document reproduces the Joint Declaration on Nuclear Policy signed by the Presidents of Argentina and Brazil on 30 November 1985, the Protocol on Nuclear Co-operation between Argentina and Brazil signed on 10 December 1986, the Joint Declaration on Nuclear Policy signed by the two Presidents on 10 December 1986, the Joint Declaration on Nuclear Policy signed by the two Presidents on 17 July 1987 and the Joint Declaration on Nuclear Policy (IPERO Declaration) signed by the two Presidents on 8 April 1988

  11. Characterization of agua de Ramon marbles, Cordoba Province, Argentina

    Tourn, S.; Castro, L. . E mail: selvia@fcen.uba.ar, lilianacastro@fibertel.com.ar

    2004-01-01

    Agua de Ramon district is located in the NW of Cordoba, Argentina, between 3 49' and 30 0 52' S and 65 0 21' and 65 0 24' W, in the Eastern Pampean Range setting. It was a very important tungsten district until the end of 1950'decade when tungsten mining became of no economic interest. The objective is to report for the first time the petrological, mineralogical and geochemical characteristics of several marble lenses located in the sourthern of the area. Marble outcrops are lenticular ranging from 1 m to 80 m in length and 0.50 m to 20 m width. They appear massive, fine-grained and in light colors (white, pale green, very light brown and pale gray). These last varieties show a distinct banded structure due to little differences in color. These marbles are mainly composed of magnesian calcite accompanied by minor amounts of dolomite, forsterite, humite group minerals, tremolite, talc, serpentine and clinochlore, and scheelite, sphene, apatite and opaque minerals like hematite, magnetite, illmenite, pirrothite and pyrite as accessory minerals. Major chemical analyses indicate a relatively high SiO2 and MgO content, and minor CaO, in comparison with marbles of this type. Mineral paragenesis was useful to evaluate metamorphism conditions in this area [es

  12. Design bases for the construction of a repository in Argentina

    Palacios, E.; Mattar, J.; Perucca, C.; Preisz, G.E.

    1984-01-01

    The Argentine nuclear programme provides for the reprocessing of spent fuel elements and the recycling of plutonium produced for the generation of electricity. As a result, high-level radioactive waste will initially arise in liquid form and will than have to be disposed of by appropriate treatment. The basic protection criteria applied for this purpose are: to avoid non-stochastic radiation hazards, to limit the risk to the individual and to reduce the collective radiological impact as far as is reasonably achievable. On the basis of these criteria, the selection of a site and a basic engineering project for the construction of a repository to meet the country's needs have been undertaken. In the first stage, some 200 potentially suitable granite occurrences distributed throughout the country were identified. A preselection was then made of granite formations which lie outside seismic areas, which are parts of stable and scarcely altered geological formations, and which also lie outside potential mining areas. Four granite outcrops were identified in this preselection as being the most promising for further study. Detailed investigations were subsequently taken up in one of the preselected granite formations which is located in the province of Chubut in southern Argentina. (author)

  13. Economics of mine water treatment

    Dvořáček, Jaroslav; Vidlář, Jiří; Štěrba, Jiří; Heviánková, Silvie; Vaněk, Michal; Barták, Pavel

    2012-01-01

    Mine water poses a significant problem in lignite coal mining. The drainage of mine water is the fundamental prerequisite of mining operations. Under the legislation of the Czech Republic, mine water that discharges into surface watercourse is subject to the permission of the state administration body in the water management sector. The permission also stipulates the limits for mine water pollution. Therefore, mine water has to be purified prior to discharge. Although all...

  14. Phytostabilization of Mine Tailings Using Compost-Assisted Direct Planting: Translating Greenhouse Results to the Field

    Gil-Loaiza, Juliana; White, Scott A.; Root, Robert A.; Solís-Dominguez, Fernando A.; Hammond, Corin M.; Chorover, Jon; Maier, Raina M.

    2016-01-01

    Standard practice in reclamation of mine tailings is the emplacement of a 15 to 90 cm soil/gravel/rock cap which is then hydro-seeded. In this study we investigate compost-assisted direct planting phytostabilization technology as an alternative to standard cap and plant practices. In phytostabilization the goal is to establish a vegetative cap using native plants that stabilize metals in the root zone with little to no shoot accumulation. The study site is a barren 62-hectare tailings pile ch...

  15. Using Pneumatics to Perform Laboratory Hydraulic Conductivity Tests on Gravel with Underdamped Responses

    Judge, A. I.

    2011-12-01

    A permeameter has been designed and built to perform laboratory hydraulic conductivity tests on various kinds of gravel samples with hydraulic conductivity values ranging from 0.1 to 1 m/s. The tests are commenced by applying 200 Pa of pneumatic pressure to the free surface of the water column in a riser connected above a cylinder that holds large gravel specimens. This setup forms a permeameter specially designed for these tests which is placed in a barrel filled with water, which acts as a reservoir. The applied pressure depresses the free surface in the riser 2 cm until it is instantly released by opening a ball valve. The water then flows through the base of the cylinder and the specimen like a falling head test, but the water level oscillates about the static value. The water pressure and the applied air pressure in the riser are measured with vented pressure transducers at 100 Hz. The change in diameter lowers the damping frequency of the fluctuations of the water level in the riser, which allows for underdamped responses to be observed for all tests. The results of tests without this diameter change would otherwise be a series of critically damped responses with only one or two oscillations that dampen within seconds and cannot be evaluated with equations for the falling head test. The underdamped responses oscillate about the static value at about 1 Hz and are very sensitive to the hydraulic conductivity of all the soils tested. These fluctuations are also very sensitive to the inertia and friction in the permeameter that are calculated considering the geometry of the permeameter and verified experimentally. Several gravel specimens of various shapes and sizes are tested that show distinct differences in water level fluctuations. The friction of the system is determined by calibrating the model with the results of tests performed where the cylinder had no soil in it. The calculation of the inertia in the response of the water column for the typical testing

  16. Operating practical experience at Argentina; Experiencia practica operativa en la Argentina

    Quihillalt, Oscar [Nucleoelectria Argentina S.A., Buenos Aires (Argentina)

    1998-12-31

    Operating experiences of Atucha-1 and Embalse Nuclear Power Plants were discussed in this work. The technical and economic aspects, such as reliability, availability, personnel training, operating costs, prices and market, which exercise influence upon Argentina nuclear energy policy, mainly on the power electric generation by nuclear power plants were considered. Finally the current status of the nucleoelectric sector in Argentina and forecasting were analysed. 3 figs., 5 tabs.

  17. Uranium mining in Sierra Pintada: knowledge, epistemic communities and development

    Martinez Demarco, S. R.

    2011-01-01

    This paper analyses the conflict triggered by the National Atomic Energy Commission of Argentina (CNEA) proposing to re-open the Mining Complex of Sierra Pintada, in San Rafael, Province of Mendoza. Since 2004 when the Commission submitted the first report to the Ministry of Public Works and Environment of Mendoza to obtain the necessary permission to restart the works in the mine, several protests have taken place and many legal measures were taken in order to stop any resuming attempts. This study argues that, although CNEA has been an epistemic community capable of applying their policy proposals in the nuclear field, their technical knowledge is currently not sufficient to design a policy, and moreover, to hold that they are working for local and sustainable development. Only 'puzzling' 'with actors' paradigms and knowledge is possible to fit together their demands and achieve a public policy, or solution, for this problem. (author) [es

  18. The spatial distribution of microfabric around gravel grains: indicator of till formation processes

    KalväNs, Andis; Saks, Tomas

    2010-05-01

    Till micromorphology studies in thin sections is an established tool in the field of glacial geology. Often the thin sections are inspected only visually with help of mineralogical microscope. This can lead to subjective interpretation of observed structures. More objective method used in till micromorphology is measurement of apparent microfabric, usually seen as preferred orientation of elongated sand grains. In theses studies only small fraction of elongated sand grains often confined to small area of thin section usually are measured. We present a method for automated measurement of almost all elongated sand grains across the full area of the thin section. Apparently elongated sand grains are measured using simple image analysis tools, the data are processed in a way similar to regular till fabric data and visualised as a grid of rose diagrams. The method allows to draw statistical information about spatial variation of microfabric preferred orientation and fabric strength with resolution as fine as 1 mm. Late Weichselian tills from several sites in Western Latvia were studied and large variations in fabric strength and spatial distribution were observed in macroscopically similar till units. The observed types of microfabric spatial distributions include strong, monomodal and uniform distribution; weak and highly variable in small distances distribution; consistently bimodal distribution and domain-like pattern of preferred sand grain orientation. We suggest that the method can be readily used to identify the basic deformation and sedimentation processes active during the final stages of till formation. It is understood that the microfabric orientation will be significant affected by nearby large particles. The till is highly heterogonous sediment and the source of microfabric perturbations observed in thin section might lie outside the section plane. Therefore we suggest that microfabric distribution around visible sources of perturbation - gravel grains cut

  19. Spatial patterns in gravel habitats and communities in the central and eastern English Channel

    Coggan, Roger; Barrio Froján, Christopher R. S.; Diesing, Markus; Aldridge, John

    2012-10-01

    The distribution of sediment type and benthic communities in the central and eastern English Channel is shown to be polarised around a distinctive local hydrodynamic feature. The seabed in the region includes an extensive area of gravel substrate which is both an important habitat for benthic marine fauna and a valuable source of material for the marine aggregate industry. Effective management of the area is predicated on an understanding of whether it represents a single homogeneous unit, or several different units that may need to be managed in different ways. The aim of this study was to provide information that would inform such management decisions. Spatial patterns in gravel habitats and communities were studied by investigating the physical environment through modelled and empirical data, and the distribution of infauna and epifauna along an east-west trending transect. A common spatial pattern was observed in both physical and biological parameters, but rather than indicating a simple longitudinal gradient, there was a distinct polarisation around a central feature, a bedload parting (BLP) zone situated between the Isle of Wight and Cotentin peninsula. Sediments and communities at the eastern and western ends of the transect were more similar to each other than to those in the middle. The strong hydrodynamic regime in the BLP area controls sediment distribution, transporting finer material, mainly sand, away from the mid transect area. The pattern in sand content of the substrate mirrors the magnitude of the potential bedload transport, which is complex in this region due to the interplay between the M2 and M4 tidal constituents and produced a series of erosional and depositional zones. The structure of benthic communities reflected the local substrate and hydrodynamic conditions, with sponges observed among the stable substrates and stronger currents that characterised the mid transect area, while infauna became more diverse towards the ends of the

  20. The morphology and morphodynamics of sand-gravel subaquatic dunes: the Raba River estuary, Poland

    Artur RADECKI-PAWLIK

    2012-08-01

    Full Text Available In the outlet of the Raba River to the Vistula, the biggest river in Poland, the morphology and morphodynamics of sand and fine-gravel subaquatic dunes were investigated. The site is situated in highland region just about the entrance to Polish Carpathians. The dunes formed on the Raba River bed estuary are composed of sand and fine gravel (d50 up to 11 mm. Systematic observation (within the 2000-2005 were made of geometry, sediment composition and hydraulic climate under which the dunes grew and decomposed. The investigation focuses here mostly on the geometrical parameters of these bed forms such as height, length, as well as granulometric characteristics of the sediment. Based on in-site measurements different hydraulic parameters were calculated such as shear stresses, resistant coefficient, Froude and Reynolds numbers and roughness coefficient. It was found that the relation between height (H and length (L of the Raba estuary dunes describes the formula: H = 0.05L0.35. Also these dunes are steeper and flatter then classical H/L index is: H/L = 0.0518L0.622. During the field campaign, when the foot access to the estuary was possible and dunes were spotted on the river bed the range of measured water velocity was from v = 0.39 m∙s-1 to v = 0.81 m∙s-1 with the highest velocity over the dune crest. At the same time the measured range of shear stresses within the dune field formation were from t = 0.115 N×m-2 to t = 1.59 N×m-2. On the field investigations the CCHE2D - two-dimensional unsteady flow and sediment transport model for non-equilibrium transport of non-uniform sediment mixtures – was applied. The model was used to simulate the morphodynamic changes along the outlet of the Raba River basing on field observations of the 2005 summer flood as well as calculate hydraulics parameters. It was also used to test and confirm the range of morphodynamic changes, which take place along the research reach where the dunes are being developed

  1. Data mining, mining data : energy consumption modelling

    Dessureault, S. [Arizona Univ., Tucson, AZ (United States)

    2007-09-15

    Most modern mining operations are accumulating large amounts of data on production and business processes. Data, however, provides value only if it can be translated into information that appropriate users can utilize. This paper emphasized that a new technological focus should emerge, notably how to concentrate data into information; analyze information sufficiently to become knowledge; and, act on that knowledge. Researchers at the Mining Information Systems and Operations Management (MISOM) laboratory at the University of Arizona have created a method to transform data into action. The data-to-action approach was exercised in the development of an energy consumption model (ECM), in partnership with a major US-based copper mining company, 2 software companies, and the MISOM laboratory. The approach begins by integrating several key data sources using data warehousing techniques, and increasing the existing level of integration and data cleaning. An online analytical processing (OLAP) cube was also created to investigate the data and identify a subset of several million records. Data mining algorithms were applied using the information that was isolated by the OLAP cube. The data mining results showed that traditional cost drivers of energy consumption are poor predictors. A comparison was made between traditional methods of predicting energy consumption and the prediction formed using data mining. Traditionally, in the mines for which data were available, monthly averages of tons and distance are used to predict diesel fuel consumption. However, this article showed that new information technology can be used to incorporate many more variables into the budgeting process, resulting in more accurate predictions. The ECM helped mine planners improve the prediction of energy use through more data integration, measure development, and workflow analysis. 5 refs., 11 figs.

  2. Material flow-based economic assessment of landfill mining processes.

    Kieckhäfer, Karsten; Breitenstein, Anna; Spengler, Thomas S

    2017-02-01

    This paper provides an economic assessment of alternative processes for landfill mining compared to landfill aftercare with the goal of assisting landfill operators with the decision to choose between the two alternatives. A material flow-based assessment approach is developed and applied to a landfill in Germany. In addition to landfill aftercare, six alternative landfill mining processes are considered. These range from simple approaches where most of the material is incinerated or landfilled again to sophisticated technology combinations that allow for recovering highly differentiated products such as metals, plastics, glass, recycling sand, and gravel. For the alternatives, the net present value of all relevant cash flows associated with plant installation and operation, supply, recycling, and disposal of material flows, recovery of land and landfill airspace, as well as landfill closure and aftercare is computed with an extensive sensitivity analyses. The economic performance of landfill mining processes is found to be significantly influenced by the prices of thermal treatment (waste incineration as well as refuse-derived fuels incineration plant) and recovered land or airspace. The results indicate that the simple process alternatives have the highest economic potential, which contradicts the aim of recovering most of the resources. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Underground coal mine subsidence impacts on surface water

    Stump, D.E. Jr.

    1992-01-01

    This paper reports that subsidence from underground coal mining alters surface water discharge and availability. The magnitude and areal extent of these impacts are dependent on many factors, including the amount of subsidence, topography, geology, climate, surface water - ground water interactions, and fractures in the overburden. There alterations may have positive and/or negative impacts. One of the most significant surface water impacts occurred in July 1957 near West Pittston, Pennsylvania. Subsidence in the Knox Mine under the Coxton Yards of the Lehigh Valley Railroad allowed part of the discharge in the Susquehanna River to flow into the mine and create a crater 200 feet in diameter and 300 feet deep. Fourteen railroad gondola cars fell into the hole which was eventually filled with rock, sand, and gravel. Other surface water impacts from subsidence may include the loss of water to the ground water system, the gaining of water from the ground water system, the creation of flooded subsidence troughs, the increasing of impoundment storage capacity, the relocation of water sources (springs), and the alteration of surface drainage patterns

  4. First symposium on mining in Latin America. Work carried out and conclusions. I. Jornadas de la mineria Iberoamericana. Desarrollo de los trabajos y conclusiones

    1983-01-01

    Aspects of the mining industry in Latin America discussed include the coal industries of Ecuador and Argentina; energy policies for Latin America; coal exploration and production of inventories of coal deposits. The coal industry and plans for coal development in Spain are also covered. Individual papers have been abstracted separately. (In Spanish)

  5. The Politics of Human Rights in Argentina

    Brysk, Alison

    2013-01-01

    Revised edition of 1994 out-of-print Stanford University Press study of human rights protest, social change, and democratization in Argentina.  A symbolic politics analysis of the truth commission, trials, and policy reform in Latin America's most sweeping transition of the 1980's.

  6. Argentina - Women Weaving Equitable Gender Relations

    Stubbs, Josefina

    2008-01-01

    In 2001, after a long period of recession, Argentina faced the greatest economic, political, and institutional crisis in its history. Unemployment reached levels nearing 18 percent and the poverty rate reached a peak of 58 percent in 2002, increasing twofold the number of people living the poverty line and impacting in a disproportionate manner the most vulnerable and poverty stricken fami...

  7. Agua potable y saneamiento en la Argentina

    Auge, Miguel

    2007-01-01

    Este trabajo fue presentado originalmente en el Foro Regional del Agua, con el título “Problemática del Acceso al Agua Potable y al Saneamiento en Argentina”. Dicho foro, organizado por la Defensoría del Pueblo de la Nación Argentina, se desarrolló en Córdoba, en mayo del 2007.

  8. Argentina and Brazil's Relations to the EU

    Christensen, Steen Fryba

    Analysen diskuterer Argentina og Brasiliens relationer til EU i nyere tid med udgangspunkt i forhandlingerne om en associeringsaftale mellem EU og Mercosur, der igangsattes efter underskrivelsen af en bi-regional rammeaftale i 1995. Fokus er i særlig grad på, hvordan disse relationer bedst forstås...

  9. Sudden death syndrome of soybean in Argentina

    Sudden death syndrome (SDS) is one of the most common and widely spread root disease affecting soybean [Glycine max (L.) Merr.] in Argentina where it is an economically important crop. This disease was first discovered in this country in 1992 in the Pampas Region, and the following year in Northwest...

  10. Payenia volcanic province, southern Mendoza, Argentina

    Søager, Nina; Holm, Paul Martin; Llambias, Eduardo Jorge

    2013-01-01

    The Pleistocene to Holocene Payenia volcanic province is a backarc region of 60,000 km2 in Mendoza, Argentina, which is dominated by transitional to alkaline basalts and trachybasalts. We present major and trace element compositions of 139 rocks from this area of which the majority are basaltic...

  11. Argentina : Gender Equity in the Private Sector

    World Bank

    2010-01-01

    First tested in Mexico in 2003, and most recently applied in 2009 in Argentina, the World Bank has developed a model to incorporate gender equity into private sector organizations while simultaneously enhancing their business. Under the model, participating organizations conduct a self-diagnosis to identify gender biases and gaps in the operations. This baseline is then used to create and ...

  12. SRTM Anaglyph: Las Bayas, Argentina

    2001-01-01

    The interplay of volcanism, stream erosion and landslides is evident in this Shuttle Radar Topography Mission view of the eastern flank of the Andes Mountains, southeast of San Carlos de Bariloche, Argentina. Older lava flows emanating from the Andes once covered much of this area. Younger, local volcanoes (seen here as small peaks) then covered parts of the area with fresh, erosion resistant flows (seen here as very smooth surfaces). Subsequent erosion has created fine patterns on the older surfaces (bottom of the image) and bolder, irregular patterns through and around the younger surfaces (upper center and right center). Meanwhile, where a large stream immediately borders the resistant plateau (center of the image), lateral erosion has undercut the resistant plateau causing slivers of it to fall into the stream channel. This scene well illustrate show topographic data alone can reveal some aspects of recent geologic history.This anaglyph was produced by first shading a preliminary elevation model from data acquired by the Shuttle Radar Topography Mission. The stereoscopic effect was then created by generating two differing perspectives, one for each eye. When viewed through special glasses, the result is a vertically exaggerated view of the Earth's surface in its full three dimensions. Anaglyph glasses cover the left eye with a red filter and cover the right eye with a blue filter.Elevation data used in this image were acquired by the Shuttle Radar Topography Mission aboard the Space Shuttle Endeavour, launched on February 11, 2000. The mission used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar that flew twice on the Space Shuttle Endeavour in 1994. The Shuttle Radar Topography Mission was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking

  13. [Adult mortality differentials in Argentina].

    Rofman, R

    1994-06-01

    Adult mortality differentials in Argentina are estimated and analyzed using data from the National Social Security Administration. The study of adult mortality has attracted little attention in developing countries because of the scarcity of reliable statistics and the greater importance assigned to demographic phenomena traditionally associated with development, such as infant mortality and fertility. A sample of 39,421 records of retired persons surviving as of June 30, 1988, was analyzed by age, sex, region of residence, relative amount of pension, and social security fund of membership prior to the consolidation of the system in 1967. The thirteen former funds were grouped into the five categories of government, commerce, industry, self-employed, and other, which were assumed to be proxies for the activity sector in which the individual spent his active life. The sample is not representative of the Argentine population, since it excludes the lowest and highest socioeconomic strata and overrepresents men and urban residents. It is, however, believed to be adequate for explaining mortality differentials for most of the population covered by the social security system. The study methodology was based on the technique of logistic analysis and on the use of regional model life tables developed by Coale and others. To evaluate the effect of the study variables on the probability of dying, a regression model of maximal verisimilitude was estimated. The model relates the logit of the probability of death between ages 65 and 95 to the available explanatory variables, including their possible interactions. Life tables were constructed by sex, region of residence, previous pension fund, and income. As a test of external consistency, a model including only age and sex as explanatory variables was constructed using the methodology. The results confirmed consistency between the estimated values and other published estimates. A significant conclusion of the study was that

  14. Collaborative Data Mining

    Moyle, Steve

    Collaborative Data Mining is a setting where the Data Mining effort is distributed to multiple collaborating agents - human or software. The objective of the collaborative Data Mining effort is to produce solutions to the tackled Data Mining problem which are considered better by some metric, with respect to those solutions that would have been achieved by individual, non-collaborating agents. The solutions require evaluation, comparison, and approaches for combination. Collaboration requires communication, and implies some form of community. The human form of collaboration is a social task. Organizing communities in an effective manner is non-trivial and often requires well defined roles and processes. Data Mining, too, benefits from a standard process. This chapter explores the standard Data Mining process CRISP-DM utilized in a collaborative setting.

  15. Coal mine site reclamation

    NONE

    2013-02-15

    Coal mine sites can have significant effects on local environments. In addition to the physical disruption of land forms and ecosystems, mining can also leave behind a legacy of secondary detrimental effects due to leaching of acid and trace elements from discarded materials. This report looks at the remediation of both deep mine and opencast mine sites, covering reclamation methods, back-filling issues, drainage and restoration. Examples of national variations in the applicable legislation and in the definition of rehabilitation are compared. Ultimately, mine site rehabilitation should return sites to conditions where land forms, soils, hydrology, and flora and fauna are self-sustaining and compatible with surrounding land uses. Case studies are given to show what can be achieved and how some landscapes can actually be improved as a result of mining activity.

  16. Treating mine water

    Matlak, E S; Kochegarova, L V; Zaslavskaya, I Yu

    1980-10-01

    Taking into account the negative influence of mine waters with suspended matter on the natural environment on the surface, the maximum treatment of mine water underground, is proposed. It is noted that full treatment of mine water, using conventional filtration methods, would be rather expensive, but a limited treatment of mine water is possible. Such treated mine water can be used in dust suppression and fire fighting systems. Mine water treated underground should be free of any odor, with pH level ranging from 6 to 9.5, with suspended matter content not exceeding 50 mg/l and coli-titre not less than 300 cm$SUP$3. It is suggested that water treatment to produce water characterized by these parameters is possible and economical. Recommendations on construction of underground sedimentation tanks and channels, and a hydraulic system of cleaning sedimentation tanks are proposed. The settling would be stored underground in abandoned workings. (2 refs.) (In Russian)

  17. Low-cost multi-stage filtration enhanced by coagulation-flocculation in upflow gravel filtration

    L. D. Sánchez

    2012-12-01

    Full Text Available This paper assesses the operational and design aspects of coagulation and flocculation in upflow gravel filters (CF-UGF in a multi-stage filtration (MSF plant. This study shows that CF-UGF units improve the performance of MSF considerably, when the system operates with turbidity above 30 NTU. It strongly reduces the load of particulate material before the water enters in the slow sand filters (SSF and therewith avoids short filter runs and prevents early interruption in SSF operations. The removal efficiency of turbidity in the CF-UGF with coagulant was between 85 and 96%, whereas the average efficiency without coagulant dosing was 46% (range: 21–76%. Operating with coagulant also improves the removal efficiency for total coliforms, E-coli and HPC. No reduction was observed in the microbial activity of the SSF, no obstruction of the SSF bed was demonstrated and SSF runs were maintained between 50 and 70 days for a maximum head loss of 0.70 m. The most important advantage is the flexibility of the system to operate with and without coagulant according to the influent turbidity. It was only necessary for 20% of the time to operate with the coagulant. The CF-UGF unit represented 7% of total construction costs and the O&M cost for the use of coagulant represented only 0.3%.

  18. Performance of a forced convection solar drier integrated with gravel as heat storage material

    Mohanraj, M. [Dr Mahalingam College of Engineering and Technology, Pollachi (India). Dept. of Mechanical Engineering; Chandrasekar, P. [Swinburne Univ. of Technology, Sarawak (Malaysia). School of Engineering Sciences

    2009-07-01

    Sun drying is the most common method used in India to dry agricultural products such as grains, fruits and vegetables. The rate of drying depends on solar radiation, ambient temperature, wind velocity, relative humidity, initial moisture content, type of crops, crop absorptivity and mass product per unit exposed area. However, this method of spreading the crop in a thin layer on the ground has several disadvantages. This paper reported on a study that focused on developing a forced convection solar drier integrated with heat storage materials for drying various agricultural crops. The indirect forced convection solar drier, integrated with gravel as a sensible heat material, was used to dry pineapple slices under conditions similar to those found in Pollachi, India. The performance of the system was discussed along with the drying characteristics, drying rate, and specific moisture extraction rate. The results showed that the moisture content (wet basis) of pineapple was reduced from about 87.5 to 14.5 per cent (equilibrium moisture content) in about 29 hours in the bottom tray and 32 hours in the top tray. The thermal efficiency of the solar air heater was also reviewed. 9 refs., 5 figs.

  19. Engineered channel controls limiting spawning habitat rehabilitation success on regulated gravel-bed rivers

    Brown, Rocko A.; Pasternack, Gregory B.

    2008-05-01

    In efforts to rehabilitate regulated rivers for ecological benefits, the flow regime has been one of the primary focal points of management strategies. However, channel engineering can impact channel geometry such that hydraulic and geomorphic responses to flow reregulation do not yield the sought for benefits. To illustrate and assess the impacts of structural channel controls and flow reregulation on channel processes and fish habitat quality in multiple life stages, a highly detailed digital elevation model was collected and analyzed for a river reach right below a dam using a suite of hydrologic, hydraulic, geomorphic, and ecological methods. Results showed that, despite flow reregulation to produce a scaled-down natural hydrograph, anthropogenic boundary controls have severely altered geomorphic processes associated with geomorphic self-sustainability and instream habitat availability in the case study. Given the similarity of this stream to many others, we concluded that the potential utility of natural flow regime reinstatement in regulated gravel-bed rivers is conditional on concomitant channel rehabilitation.

  20. Performance evaluation and modelling studies of gravel--coir fibre--sand multimedia stormwater filter.

    Samuel, Manoj P; Senthilvel, S; Tamilmani, D; Mathew, A C

    2012-09-01

    A horizontal flow multimedia stormwater filter was developed and tested for hydraulic efficiency and pollutant removal efficiency. Gravel, coconut (Cocos nucifera) fibre and sand were selected as the media and filled in 1:1:1 proportion. A fabric screen made up of woven sisal hemp was used to separate the media. The adsorption behaviour of coir fibre was determined in a series of column and batch studies and the corresponding isotherms were developed. The hydraulic efficiency of the filter showed a diminishing trend as the sediment level in inflow increased. The filter exhibited 100% sediment removal at lower sediment concentrations in inflow water (>6 g L(-1)). The filter could remove NO3(-), SO4(2-) and total solids (TS) effectively. Removal percentages of Mg(2+) and Na(+) were also found to be good. Similar results were obtained from a field evaluation study. Studies were also conducted to determine the pattern of silt and sediment deposition inside the filter body. The effects of residence time and rate of flow on removal percentages of NO3(-) and TS were also investigated out. In addition, a multiple regression equation that mathematically represents the filtration process was developed. Based on estimated annual costs and returns, all financial viability criteria (internal rate of return, net present value and benefit-cost ratio) were found favourable and affordable to farmers for investment in the developed filtration system. The model MUSIC was calibrated and validated for field conditions with respect to the developed stormwater filter.

  1. Measuring gravel transport and dispersion in a mountain river using passive radio tracers

    Bradley, D. N.; Tucker, G. E.

    2012-01-01

    Random walk models of fluvial sediment transport recognize that grains move intermittently, with short duration steps separated by rests that are comparatively long. These models are built upon the probability distributions of the step length and the resting time. Motivated by these models, tracer experiments have attempted to measure directly the steps and rests of sediment grains in natural streams. This paper describes results from a large tracer experiment designed to test stochastic transport models. We used passive integrated transponder (PIT) tags to label 893 coarse gravel clasts and placed them in Halfmoon Creek, a small alpine stream near Leadville, Colorado, USA. The PIT tags allow us to locate and identify tracers without picking them up or digging them out of the streambed. They also enable us to find a very high percentage of our rocks, 98% after three years and 96% after the fourth year. We use the annual tracer displacement to test two stochastic transport models, the Einstein–Hubbell–Sayre (EHS) model and the Yang–Sayre gamma-exponential model (GEM). We find that the GEM is a better fit to the observations, particularly for slower moving tracers and suggest that the strength of the GEM is that the gamma distribution of step lengths approximates a compound Poisson distribution. Published in 2012. This article is a US Government work and is in the public domain in the USA.

  2. A new approach to define surface/sub-surface transition in gravel beds

    Haynes, Heather; Ockelford, Anne-Marie; Vignaga, Elisa; Holmes, William

    2012-12-01

    The vertical structure of river beds varies temporally and spatially in response to hydraulic regime, sediment mobility, grain size distribution and faunal interaction. Implicit are changes to the active layer depth and bed porosity, both critical in describing processes such as armour layer development, surface-subsurface exchange processes and siltation/ sealing. Whilst measurements of the bed surface are increasingly informed by quantitative and spatial measurement techniques (e.g., laser displacement scanning), material opacity has precluded the full 3D bed structure analysis required to accurately define the surface-subsurface transition. To overcome this problem, this paper provides magnetic resonance imaging (MRI) data of vertical bed porosity profiles. Uniform and bimodal (σ g = 2.1) sand-gravel beds are considered following restructuring under sub-threshold flow durations of 60 and 960 minutes. MRI data are compared to traditional 2.5D laser displacement scans and six robust definitions of the surface-subsurface transition are provided; these form the focus of discussion.

  3. Migration rates of volatile organic compounds in an unconsolidated sand and gravel aquifer system

    Naidu, J.R.; Paquette, D.E.; Porcelli, D.R.

    1993-01-01

    The movement of volatile organic compounds (VOCs) in an aquifer is dictated by its solubility, attenuation characteristics, recharge volume, and ground-water movement (velocity and direction). At Brookhaven National Laboratory, past handling and disposal practices at the Hazardous Waste Management Facility and current landfill have resulted in the release of VOCs and the radioisotope tritium to the underlying upper glacial aquifer which characterized by unconsolidated sands and gravel. The rate of VOC migration from these source areas was examined using the following parameters: (1) distribution of VOCs and tritium; (2) tritium/helium ratios, which provide an estimate of the age of the water, and hence the rate of ground-water movement; (3) ground-water flow velocities within the upper glacial aquifer utilizing conductivity, porosity, and gradient data. Preliminary results indicate that whereas the comparison of the calculated ground-water flow gradient to tritium/helium age determinations are fairly consistent, application to VOC movement is inconclusive, and will require additional monitoring which would also focus on the vertical component as well

  4. PGDP Trichloroethene Biodegradation Investigation Summary Report: Regional Gravel Aquifer & Northwest Plume

    Hampson, Steve [Univ. of Kentucky, Lexington, KY (United States). Kentucky Research Consortium for Energy and Environment

    2008-09-01

    The evaluation of biological degradation processes addressed by this report are part of a broad trichloroethene (TCE) Fate and Transport Investigation that includes four (4) topics of phased investigation (Table ES1) relative to degradation and/or attenuation of TCE in the Regional Gravel Aquifer (RGA) underlying the United States Department of Energy Paducah Gaseous Diffusion Plant (PGDP). In order of implementation the project phases are: (1) derivation of a TCE first-order rate constant by normalization of TCE values against technetium-99 (99Tc) and chloride. 2) identification of the presence of microbes capable of aerobic co-metabolic TCE biodegradation using enzyme activity probes (this report); 3) Compound-specific isotope analysis (CSIA) to support prevalence of biotic and/or abiotic degradation processes; and 4) evaluation of potential abiotic RGA-TCE attenuation mechanisms including sorption. This report summarizes the Phase II activities related to the identification and evaluation of biological degradation processes that may be actively influencing TCE fate and transport in the RGA contaminant plumes at the United States Department of Energy (DOE) PGDP and its environs (Figure ES1). The goals of these activities were to identify active biological degradation mechanisms in the RGA through multiple lines of evidence and to provide DOE with recommendations for future TCE biological degradation investigations.

  5. Computational fluid dynamics and experimental tests helping to understand the gravel pack displacement in petroleum wells; Fluidodinamica computacional (CFD) e testes experimentais ajudam a compreender o fenomeno do deslocamento do gravel pack em pocos de petroleo

    Magalhaes, Joao Vicente Martins de; Leal, Rafael Amorim Ferreira; Martins, Andre Leibsohn; Calderon, Agostinho; Ferreira, Marcus Vinicius Duarte [Petrobras S.A., Rio de Janeiro, RJ (Brazil)], E-mails: ivmm@petrobras.com.br, rafaelleal@petrobras.com.br, aleibsohn@petrobras.com.br, agoscal@petrobras.com.br, mvdferreira@petrobras.com.br; Simoes, Bruno; Barbosa, Diego [Halliburton, Novo Cavaleiros, Macae, RJ (Brazil)], E-mails: bruno.simoes@halliburton.com.br, diego.barbosa@halliburton.com.br

    2010-07-01

    In the petroleum exploitation and production in deep water, at the fields operated by PETROBRAS, Brazil, one of the problems frequently found is the need of elimination of sand production, having in mind that the most of those fields produce from the non consolidated sandstones. The opened well Gravel Packing is the technique most used for that task. Due to the fact of Gravel Packing operations occurs at thousand of meters below the surface, it is necessary the computational simulation for forecasting how particle deposition (Gravel) in the well occurs. So, it was used the commercial pack of fluid dynamics FLUENT 12, which calculates the fluid velocity field, coupled to another commercial pack, the EDEM, based on discrete elements that treat of particle mechanics. The coupling of the two software has shown adequate the comparison of the computational results with the experimental data shows a good adjustment. Besides, it was possible to simulate problems of well early clogging, showing that the computational simulation is strong and capable of captivating such a phenomena.

  6. Experimental tests and computational fluid dynamics (CFD) helps in determination the new operational limits for gravel packing; Testes experimentais e simulacoes em fluidodinamica computacional (CFD) auxiliam na determinacao de novos limites operacionais para o gravel packing

    Magalhaes, Joao Vicente Martins de [PETROBRAS, Santos, SP (Brazil). E e P Construcao de Pocos Maritimos. Construcao e Manutencao de Pocos], e-mail: jvmm@petrobras.com.br; Calderon, Agostinho [PETROBRAS, rj (bRAZIL). E e P Construcao de Pocos Maritimos. Construcao e Manutencao de Pocos], e-mail: agoscal@petrobras.com.br; Leal, Rafael Amorim Ferreira [Centro de Pesquisas da Petrobras (CENPES), RJ (Brazil). P e D em Geoengenharia e Engenharia de Poco. Gerencia de Perfuracao e Completacao de Pocos], e-mail: rafaelleal@petrobras.com.br; Miranda, Daniel Bonavides [Halliburton Energy Services (Brazil)], e-mail: daniel.miranda@halliburton.com; Simoes, Bruno Campos; Nunes, Mauro Jose de Souza Custodio [Halliburton Brasil. Setor de Estimulacao e Controle de Areia (Brazil)], e-mails: bruno.simoes@halliburton.com, mauro.nunes@halliburton.com; Barbosa, Diego Paiva [Halliburton Brasil. Coordenador de Servicos de Campo (Brazil)], e-mail: diego.barbosa@halliburton.com; Souza, Jairo Zago de [Engineering Simulation and Scientific Software - ESSS (Brazil)], e-mail: jairo@esss.com.br

    2010-06-15

    Open hole Gravel Packing was the sand control strategy adopted by PETROBRAS while developing Campos Basin fields. One of the big problems in the oil industry is based on stems from the fact of that all the whole operations are carried out many thousands of feet in the underground, without direct visualization supervision. All the controls used in the operations are based upon direct and/or indirect measurements, but without, however, the necessary visual aid. This was the motivator for the construction of an experimental device that could simulate both the open well and the rat-hole allowing the study of how the deposition of Gravel occurs around the screens. Such experimental apparatus was built with casing pipes it which common rat-hole/open-hole inside diameters (12 1/'' and 8 1/2''). For the tests representativeness the simulator was equipped with real screens and wash pipes, reproducing the real operation dynamics. In the apparatus it was possible: to see Gravel settling through acrylic windows, to test new low-cost proppants and new concentrations, to define new minimal pump operational rates, as well as to record by filming the turbulent structures that occurs at the rat-hole/open-hole contraction zone. This paper treats of these results release and show CFD results used to enlarge test matrix. (author)

  7. Treatment of mine-water from decommissioning uranium mines

    Fan Quanhui

    2002-01-01

    Treatment methods for mine-water from decommissioning uranium mines are introduced and classified. The suggestions on optimal treatment methods are presented as a matter of experience with decommissioned Chenzhou Uranium Mine

  8. Implementation of Paste Backfill Mining Technology in Chinese Coal Mines

    Chang, Qingliang; Zhou, Huaqiang; Bai, Jianbiao

    2014-01-01

    Implementation of clean mining technology at coal mines is crucial to protect the environment and maintain balance among energy resources, consumption, and ecology. After reviewing present coal clean mining technology, we introduce the technology principles and technological process of paste backfill mining in coal mines and discuss the components and features of backfill materials, the constitution of the backfill system, and the backfill process. Specific implementation of this technology and its application are analyzed for paste backfill mining in Daizhuang Coal Mine; a practical implementation shows that paste backfill mining can improve the safety and excavation rate of coal mining, which can effectively resolve surface subsidence problems caused by underground mining activities, by utilizing solid waste such as coal gangues as a resource. Therefore, paste backfill mining is an effective clean coal mining technology, which has widespread application. PMID:25258737

  9. A mine of energy

    Fallon, M.

    1982-01-01

    In July 1978 the then Union Corporation (which is a wholly-owned Subsidiary of the larger Gencor Group) announced its intention to develop Beisa mine in the Orange Free State. They started up a medium sized uranium mine with gold as a by-product. The main idea was for the processing of uranium. The planning of the uranium recovery plant, the actual mining, and the recovery and extraction of uranium are discussed

  10. Uranium mining in Saskatchewan

    Scales, M.

    2006-01-01

    The mines of northern Saskatchewan make Canada the worlds leading uranium producer in Canada supplied 29% of global demand, or 11.60 million tonnes of the metal in 2004. Here are two bright ideas - how to mine an orebody by neither pit nor underground method, and how to mine high-grade ore without miners - that Cogema and Cameco are pursuing in the Athabasca Basin

  11. Towards Rare Itemset Mining

    Szathmary , Laszlo; Napoli , Amedeo; Valtchev , Petko

    2007-01-01

    site de la conférence : http://ictai07.ceid.upatras.gr/; International audience; We describe here a general approach for rare itemset mining. While mining literature has been almost exclusively focused on frequent itemsets, in many practical situations rare ones are of higher interest (e.g., in medical databases, rare combinations of symptoms might provide useful insights for the physicians). Based on an examination of the relevant substructures of the mining space, our approach splits the ra...

  12. Partnership in mining

    Haslam, R

    1988-04-01

    This paper discusses the benefits resulting from mutual cooperation and information exchange between the UK and USA coal industries. The aim of this cooperation is to promote safe and efficient extraction and profitable use of coal. Advanced mining technologies and mechanisation of the coal mines are some of the results of research cooperation between British Coal and the US Bureau of Mines. In addition, Britain has studied and put into good use the management styles, working practices and pay structure, and mining engineering adopted in the USA.

  13. Solution mining economics

    Hunkin, G.G.

    1980-01-01

    The field of application of in-situ solution mining of uranium is described and areas of competition with open pit and underground mining identified. The influence of high interest rates and dollar inflation on present values and rate of return is shown to be minimized by low capitalization and short construction lead times typical of in-situ leaching ventures. A scheme of three major project account divisions is presented and basic parameters necessary for mine planning are listed. 1979 cost ranges and useful methods of estimation of capital and operating costs are given for the in-situ uranium mining method

  14. Mining face equipment

    G, Litvinskiy G; Babyuk, G V; Yakovenko, V A

    1981-01-07

    Mining face equipment includes drilling advance wells, drilling using explosives on the contour bore holes, loading and transporting the crushed mass, drilling reinforcement shafts, injecting reinforcement compounds and moving the timber. Camouflet explosives are used to form relaxed rock stress beyond the mining area to decrease costs of reinforcing the mining area by using nonstressed rock in the advance well as support. The strengthening solution is injected through advanced cementing wells before drilling the contour bores as well as through radial cementing wells beyond the timbers following loading and transport of the mining debris. The advance well is 50-80 m.

  15. The mines of Jackymov

    Ramsey, L.J.

    1985-01-01

    The history of the mines in the vicinity of Jackymov, a small town in Central Europe is given. These mines have been worked for several hundred years and from them has been brought forth a variety of products including silver, uranium and radium, the latter being isolated from Jackymov pitch-blende and identified by Marie Curie. The health effects of the miners mining radioactive ores are briefly discussed. The development of Jackymov as a spa resort using the mine water containing radium is also described. (U.K.)

  16. Uranium mining and milling

    Floeter, W.

    1976-01-01

    In this report uranium mining and milling are reviewed. The fuel cycle, different types of uranium geological deposits, blending of ores, open cast and underground mining, the mining cost and radiation protection in mines are treated in the first part of this report. In the second part, the milling of uranium ores is treated, including process technology, acid and alkaline leaching, process design for physical and chemical treatment of the ores, and the cost. Each chapter is clarified by added figures, diagrams, tables, and flowsheets. (HK) [de

  17. Mine ventilation engineering

    Hall, C.J.

    1981-01-01

    This book on mine ventilation covers psychometrics, airflow through roadways and ducts, natural ventilation, fans, instruments, ventilation surveys, auxiliary ventilation, air quality, and planning and economics.

  18. Responsible Mining: A Human Resources Strategy for Mine Development Project

    Sampathkumar, Sriram (Ram)

    2012-01-01

    Mining is a global industry. Most mining companies operate internationally, often in remote, challenging environments and consequently frequently have respond to unusual and demanding Human Resource (HR) requirements. It is my opinion that the strategic imperative behind success in mining industry is responsible mining. The purpose of this paper is to examine how an effective HR strategy can be a competitive advantage that contributes to the success of a mining project in the global mining in...

  19. Mining engineer requirements in a German coal mine

    Rauhut, F J

    1985-10-01

    Basic developments in German coal mines, new definitions of working areas of mining engineers, and groups of requirements in education are discussed. These groups include: requirements of hard-coal mining at great depth and in extended collieries; application of process technology and information systems in semi-automated mines; thinking in processes and systems; organizational changes; future requirements of mining engineers; responsibility of the mining engineer for employees and society.

  20. A Laboratory Experiment on the Evolution of a Sand Gravel Reach Under a Lack of Sediment Supply

    Orru, C.; Chavarrias, V.; Ferrara, V.; Blom, A.

    2014-12-01

    A flume experiment was conducted to examine the evolution of a sand-gravel reach under a lack of sediment supply. The experimental data are used to validate a numerical sand-gravel model. A bed composed of a bi-modal sediment mixture is installed with a uniform slope and an imposed gradual fining pattern. Initially, the sand fraction gradually increases in streamwise direction until the bed is fully composed of sand. The water discharge and downstream water level were constant, and the sediment feed rate was equal to zero. The experiment was dominated by bed load, partial transport, and a subcritical flow regime was imposed. The flow rate was such that only sand was mobile (partial transport), which led to a coarsening over the upstream reach and a gradual reduction of the sediment transport rate during the experiment. New equipment was used to measure the evolution of the grain size distribution of the bed surface during the experiment over the entire flume using image analysis. In the upstream reach we observed a gradual coarsening over time and the formation of an armour layer, which resulted in a more abrupt transition in grain size of the bed surface. Bed degradation increased in streamwise direction. This is due to the initial streamwise increase in the availability of sand in the bed. The different volume fraction content of sand in the bed allowed for the gravel to sink more in the downstream part of the upstream reach. The sand reach suffered from a larger degradation. Finally, we see one reach dominated by sand, small bedforms, and a small bed slope, and a gravel reach dominated by a larger bed slope.

  1. The effects of flooding disturbance on the distribution and behaviour of riparian arthropods along a lowland gravel river

    Lambeets, Kevin

    2009-01-01

    This Ph.D.-thesis aimed to address which environmental factors influence the assemblage structure of mobile, riparian arthropods along spatially structured river banks of a rain-fed, lowland gravel river, the Common Meuse. As riverine ecosystems are basically non-equilibrium, dynamic ecosystems, mainly flow regimes and flood pulse characteristics are expected to shape both the distribution and behaviour of its inhabitants. The river banks along the Common Meuse are (in)frequently disturbed by...

  2. A New Method for Tracking Individual Particles During Bed Load Transport in a Gravel-Bed River

    Tremblay, M.; Marquis, G. A.; Roy, A. G.; Chaire de Recherche Du Canada En Dynamique Fluviale

    2010-12-01

    Many particle tracers (passive or active) have been developed to study gravel movement in rivers. It remains difficult, however, to document resting and moving periods and to know how particles travel from one deposition site to another. Our new tracking method uses the Hobo Pendant G acceleration Data Logger to quantitatively describe the motion of individual particles from the initiation of movement, through the displacement and to the rest, in a natural gravel river. The Hobo measures the acceleration in three dimensions at a chosen temporal frequency. The Hobo was inserted into 11 artificial rocks. The rocks were seeded in Ruisseau Béard, a small gravel-bed river in the Yamaska drainage basin (Québec) where the hydraulics, particle sizes and bed characteristics are well known. The signals recorded during eight floods (Summer and Fall 2008-2009) allowed us to develop an algorithm which classifies the periods of rest and motion. We can differentiate two types of motion: sliding and rolling. The particles can also vibrate while remaining in the same position. The examination of the movement and vibration periods with respect to the hydraulic conditions (discharge, shear stress, stream power) showed that vibration occurred mostly before the rise of hydrograph and allowed us to establish movement threshold and response times. In all cases, particle movements occurred during floods but not always in direct response to increased bed shear stress and stream power. This method offers great potential to track individual particles and to establish a spatiotemporal sequence of the intermittent transport of the particle during a flood and to test theories concerning the resting periods of particles on a gravel bed.

  3. Hydraulic characterisation of iron-oxide-coated sand and gravel based on nuclear magnetic resonance relaxation mode analyses

    S. Costabel

    2018-03-01

    Full Text Available The capability of nuclear magnetic resonance (NMR relaxometry to characterise hydraulic properties of iron-oxide-coated sand and gravel was evaluated in a laboratory study. Past studies have shown that the presence of paramagnetic iron oxides and large pores in coarse sand and gravel disturbs the otherwise linear relationship between relaxation time and pore size. Consequently, the commonly applied empirical approaches fail when deriving hydraulic quantities from NMR parameters. Recent research demonstrates that higher relaxation modes must be taken into account to relate the size of a large pore to its NMR relaxation behaviour in the presence of significant paramagnetic impurities at its pore wall. We performed NMR relaxation experiments with water-saturated natural and reworked sands and gravels, coated with natural and synthetic ferric oxides (goethite, ferrihydrite, and show that the impact of the higher relaxation modes increases significantly with increasing iron content. Since the investigated materials exhibit narrow pore size distributions, and can thus be described by a virtual bundle of capillaries with identical apparent pore radius, recently presented inversion approaches allow for estimation of a unique solution yielding the apparent capillary radius from the NMR data. We found the NMR-based apparent radii to correspond well to the effective hydraulic radii estimated from the grain size distributions of the samples for the entire range of observed iron contents. Consequently, they can be used to estimate the hydraulic conductivity using the well-known Kozeny–Carman equation without any calibration that is otherwise necessary when predicting hydraulic conductivities from NMR data. Our future research will focus on the development of relaxation time models that consider pore size distributions. Furthermore, we plan to establish a measurement system based on borehole NMR for localising iron clogging and controlling its remediation

  4. Efficiency of phenol biodegradation by planktonic Pseudomonas pseudoalcaligenes (a constructed wetland isolate) vs. root and gravel biofilm.

    Kurzbaum, Eyal; Kirzhner, Felix; Sela, Shlomo; Zimmels, Yoram; Armon, Robert

    2010-09-01

    In the last two decades, constructed wetland systems gained increasing interest in wastewater treatment and as such have been intensively studied around the world. While most of the studies showed excellent removal of various pollutants, the exact contribution, in kinetic terms, of its particular components (such as: root, gravel and water) combined with bacteria is almost nonexistent. In the present study, a phenol degrader bacterium identified as Pseudomonas pseudoalcaligenes was isolated from a constructed wetland, and used in an experimental set-up containing: plants and gravel. Phenol removal rate by planktonic and biofilm bacteria (on sterile Zea mays roots and gravel surfaces) was studied. Specific phenol removal rates revealed significant advantage of planktonic cells (1.04 × 10(-9) mg phenol/CFU/h) compared to root and gravel biofilms: 4.59 × 10(-11)-2.04 × 10(-10) and 8.04 × 10(-11)-4.39 × 10(-10) (mg phenol/CFU/h), respectively. In batch cultures, phenol biodegradation kinetic parameters were determined by biomass growth rates and phenol removal as a function of time. Based on Haldane equation, kinetic constants such as μ(max) = 1.15/h, K(s) = 35.4 mg/L and K(i) = 198.6 mg/L fit well phenol removal by P. pseudoalcaligenes. Although P. pseudoalcaligenes planktonic cells showed the highest phenol removal rate, in constructed wetland systems and especially in those with sub-surface flow, it is expected that surface associated microorganisms (biofilms) will provide a much higher contribution in phenol and other organics removal, due to greater bacterial biomass. Factors affecting the performance of planktonic vs. biofilm bacteria in sub-surface flow constructed wetlands are further discussed. Copyright © 2010 Elsevier Ltd. All rights reserved.

  5. Hydraulic characterisation of iron-oxide-coated sand and gravel based on nuclear magnetic resonance relaxation mode analyses

    Costabel, Stephan; Weidner, Christoph; Müller-Petke, Mike; Houben, Georg

    2018-03-01

    The capability of nuclear magnetic resonance (NMR) relaxometry to characterise hydraulic properties of iron-oxide-coated sand and gravel was evaluated in a laboratory study. Past studies have shown that the presence of paramagnetic iron oxides and large pores in coarse sand and gravel disturbs the otherwise linear relationship between relaxation time and pore size. Consequently, the commonly applied empirical approaches fail when deriving hydraulic quantities from NMR parameters. Recent research demonstrates that higher relaxation modes must be taken into account to relate the size of a large pore to its NMR relaxation behaviour in the presence of significant paramagnetic impurities at its pore wall. We performed NMR relaxation experiments with water-saturated natural and reworked sands and gravels, coated with natural and synthetic ferric oxides (goethite, ferrihydrite), and show that the impact of the higher relaxation modes increases significantly with increasing iron content. Since the investigated materials exhibit narrow pore size distributions, and can thus be described by a virtual bundle of capillaries with identical apparent pore radius, recently presented inversion approaches allow for estimation of a unique solution yielding the apparent capillary radius from the NMR data. We found the NMR-based apparent radii to correspond well to the effective hydraulic radii estimated from the grain size distributions of the samples for the entire range of observed iron contents. Consequently, they can be used to estimate the hydraulic conductivity using the well-known Kozeny-Carman equation without any calibration that is otherwise necessary when predicting hydraulic conductivities from NMR data. Our future research will focus on the development of relaxation time models that consider pore size distributions. Furthermore, we plan to establish a measurement system based on borehole NMR for localising iron clogging and controlling its remediation in the gravel pack of

  6. Sustainable Mining Environment: Technical Review of Post-mining Plans

    Restu Juniah

    2017-12-01

    Full Text Available The mining industry exists because humans need mining commodities to meet their daily needs such as motor vehicles, mobile phones, electronic equipment and others. Mining commodities as mentioned in Government Regulation No. 23 of 2010 on Implementation of Mineral and Coal Mining Business Activities are radioactive minerals, metal minerals, nonmetallic minerals, rocks and coal. Mineral and coal mining is conducted to obtain the mining commodities through production operations. Mining and coal mining companies have an obligation to ensure that the mining environment in particular after the post production operation or post mining continues. The survey research aims to examine technically the post-mining plan in coal mining of PT Samantaka Batubara in Indragiri Hulu Regency of Riau Province towards the sustainability of the mining environment. The results indicate that the post-mining plan of PT Samantaka Batubara has met the technical aspects required in post mining planning for a sustainable mining environment. Postponement of post-mining land of PT Samantaka Batubara for garden and forest zone. The results of this study are expected to be useful and can be used by stakeholders, academics, researchers, practitioners and associations of mining, and the environment.

  7. The Grain-size Patchiness of Braided Gravel-Bed Streams - example of the Urumqi River (northeast Tian Shan, China)

    Guerit, L.; Barrier, L.; Narteau, C.; Métivier, F.; Liu, Y.; Lajeunesse, E.; Gayer, E.; Meunier, P.; Malverti, L.; Ye, B.

    2014-02-01

    In gravel-bed rivers, sediments are often sorted into patches of different grain-sizes, but in braided streams, the link between this sorting and the channel morpho-sedimentary elements is still unclear. In this study, the size of the bed sediment in the shallow braided gravel-bed Urumqi River is characterized by surface-count and volumetric sampling methods. Three morpho-sedimentary elements are identified in the active threads of the river: chutes at flow constrictions, which pass downstream to anabranches and bars at flow expansions. The surface and surface-layer grain-size distributions of these three elements show that they correspond to only two kinds of grain-size patches: (1) coarse-grained chutes, coarser than the bulk river bed, and (2) finer-grained anabranches and bars, consistent with the bulk river bed. In cross-section, the chute patches are composed of one coarse-grained top layer, which can be interpreted as a local armour layer overlying finer deposits. In contrast, the grain size of the bar-anabranch patches is finer and much more homogeneous in depth than the chute patches. Those patches, which are features of lateral and vertical sorting associated to the transport dynamics that build braided patterns, may be typical of active threads in shallow gravel-bed rivers and should be considered in future works on sorting processes and their geomorphologic and stratigraphic results.

  8. A study of the influence of a gravel subslab layer on radon entry rate using two basement structures

    Robinson, A.L.; Sextro, R.G.; Fisk, W.J.; Garbesi, K.; Wooley, J.; Wollenberg, H.A.

    1993-01-01

    In buildings with elevated radon concentrations, the dominant transport mechanism of radon is advective flow of soil gas into the building substructure. However, the building-soil system is often complex, making detailed studies of the radon source term difficult. In order to examine radon entry into buildings, the authors have constructed two room-size, precisely-fabricated basement structures at a site with relatively homogeneous, moderately permeable soil. The basements are identical except that one lies directly on native soil whereas the other lies on a high permeability aggregate layer. The soil pressure field and radon entry rate have been measured for different basement pressures and environmental conditions. The subslab gravel layer greatly enhances the advective entry of radon into the structure; when the structures are depressurized, the radon entry rate into the structure with the subslab gravel layer is more than a factor of 3 times the radon entry rate into the other structure for the same depressurization. The gravel subslab layer also spreads the pressure field around the structure, extending the field of influence of the structure and the region from which it draws radon

  9. The relative contribution of near-bed vs. intragravel horizontal transport to fine sediment accumulation processes in river gravel beds

    Casas-Mulet, Roser; Lakhanpal, Garima; Stewardson, Michael J.

    2018-02-01

    Understanding flow-sediment interactions is important for comprehending river functioning. Fine sediment accumulation processes, in particular, have key implications for ecosystem health. However, the amount of fines generated by intragravel flows and later accumulated in gravel streambeds may have been underestimated, as the hydraulic-related driving transport mechanisms in play are not clearly identified. Specifically, the relative contribution of fines from upper vs. lower sediment layers in gravel beds is not well understood. By recreating flooded and dewatered conditions in an experimental flume filled with natural sediment, we estimated such contributions by observing and collecting intragravel transported fines that were later accumulated into a void in the middle of the sediment matrix. Near-bed transport in the upper sediment layers (named Brinkman load) during flooded conditions accounted for most (90%) of the accumulated fines. Intragravel transport in the lower sediment layers (named Interstitial load) was the sole source of transport and accumulation during dewatered conditions with steeper hydraulic gradients. Interstitial load accounted for 10% of the total transport during flooded conditions. Although small, such estimations demonstrate that hydraulic-gradient transport in the lower sediment layers occurs in spite of the contradicting analytical assessments. We provide a case study to challenge the traditional approaches of assessing intragravel transport, and a useful framework to understand the origin and relative contribution of fine sediment accumulation in gravel beds. Such knowledge will be highly useful for the design of monitoring programs aiding river management, particularly in regulated rivers.

  10. A study of the influence of a gravel subslab layer on radon entry rate using two basement structures

    Robinson, A.L.; Sextro, R.G.; Fisk, W.J.; Garbesi, K.; Wooley, J.; Wollenberg, H.A.

    1993-01-01

    In buildings with elevated radon concentrations, the dominant transport mechanism of radon is advective flow of soil gas into the building substructure. However, the building-soil system is often complex, making detailed studies of the radon source term difficult. In order-to examine radon entry into buildings, we have constructed two room-size, precisely-fabricated basement structures at a site with relatively homogeneous, moderately permeable soil. The basements are identical except that one lies directly on native soil whereas the other lies on a high permeability aggregate layer. The soil pressure field and radon entry rate have been measured for different basement pressures and environmental conditions. The subslab gravel layer greatly enhances the advective entry of radon into the structure; when the structures are depressurized, the radon entry rate into the structure with the subslab gravel layer is more than a factor of 3 times the radon entry rate into the other structure for the same depressurization. The gravel subslab layer also spreads the pressure field around the structure, extending the field of influence of the structure and the region from which it draws radon. (orig.). (7 refs., 3 figs.)

  11. Mining robotics sensors

    Green, JJ

    2012-04-01

    Full Text Available of threedimensional cameras (SR 4000 and XBOX Kinect) and a thermal imaging sensor (FLIR A300) in order to create 3d thermal models of narrow mining stopes. This information can be used in determining the risk of rockfall in an underground mine, which is a major...

  12. Cementitious backfill in mining

    Taute, A; Spice, J; Wingrove, A C [Van Niekerk, Kleyn Edwards (South Africa)

    1993-03-01

    This article describes the need for increased usage of backfill material in mining and presents some of the considerations for use of cemented materials. Laboratory test results obtained using a variety of cementitious binders and mine tailings are presented. 3 figs., 1 tab.

  13. Mining Department computer systems

    1979-09-01

    Describes the main computer systems currently available, or being developed by the Mining Department of the UK National Coal Board. They are primarily for the use of mining and specialist engineers, but some of them have wider applications, particularly in the research and development and management statistics fields.

  14. Genetic process mining

    Aalst, van der W.M.P.; Alves De Medeiros, A.K.; Weijters, A.J.M.M.; Ciardo, G.; Darondeau, P.

    2005-01-01

    The topic of process mining has attracted the attention of both researchers and tool vendors in the Business Process Management (BPM) space. The goal of process mining is to discover process models from event logs, i.e., events logged by some information system are used to extract information about

  15. Ghana - Mining and Development

    Mohan, P.C.

    2004-01-01

    The objectives of the project ($9.37 million, 1996-2001) were to (a) enhance the capacity of the mining sector institutions to carry out their functions of encouraging and regulating investments in the mining sector in an environmentally sound manner and (b) support the use of techniques and mechanisms that will improve productivity, financial viability and reduce the environmental impact of ...

  16. Northeast Church Rock Mine

    Northeast Church Rock Mine, a former uranium mine 17 miles northeast of Gallup, NM in the Pinedale Chapter of the Navajo Nation. EPA is working with NNEPA to oversee cleanup work by United Nuclear Corporation, a company owned by General Electric (GE).

  17. Distributed genetic process mining

    Bratosin, C.C.; Sidorova, N.; Aalst, van der W.M.P.

    2010-01-01

    Process mining aims at discovering process models from data logs in order to offer insight into the real use of information systems. Most of the existing process mining algorithms fail to discover complex constructs or have problems dealing with noise and infrequent behavior. The genetic process

  18. Biodiversity information system of the national parks administration of Argentina

    Leonidas Lizarraga

    2014-06-01

    Full Text Available Introduction The Biodiversity Information System (BIS of the National Parks Administration of Argentina (NPA was launched in 2002, with the support of the Global Environmental Fund (GEF through the Biodiversity Conservation Project in Argentina. The BIS consists of a set of thematic databases and Geographic Information System (GIS set to support management decisions, and to provide information to the general public on the national protected areas of Argentina. Currently, the BIS-NPA progr...

  19. Assessment of Large Wood budget in the gravel-bed Piave River: first attempt

    Tonon, Alessia; Picco, Lorenzo; Ravazzolo, Diego; Aristide Lenzi, Mario

    2015-04-01

    During the last decades, the dynamics of large wood (LW) in rivers were analyzed to consider and define the LW budget. The space-time variations of LW amount results from the differences among input (e.g. fluvial transport, lateral recruitment) and output (e.g. fluvial transport, overbank deposition, natural chronic dead) of LW along a riverine environment. Different methodologies were applied in several fluvial environments, however in large river systems characterized by complex LW dynamics, the processes are still poor quantified. Aim of this contribution is to perform a LW budget estimation over the short period, assessing the effect of an over bankfull flood (Q=1039 m3 s-1; R.I=3.5 years). The research was carried out along a 1 km-long reach (around 15 ha) located into the middle course of the large gravel-bed Piave River (North East of Italy). The LW budget has been defined considering the recruitment through bank erosion and the fluvial transport of LW into and out of the study reach. The former factor was achieved integrating field data on riparian vegetation with the monitoring of riverbanks with a Differential Global Positioning System (DGPS). The latter was obtained detecting all LW elements (diameter ≥ 0.10 m and/or length ≥ 1 m) stored along the study reach, before and after the flood. For each LW the GPS position was recorded and a numbered tag was installed with the addition of colored paint to permit a rapid post-event recovery. Preliminary results indicate that, along the study area, the floating transport of LW is one of the most significant processes able to modify the amount of LW deposited along a riverine system. In fact, considering the input of LW, the 99.4 % (102 m3 km-1) comes from upstream due to floating, whereas the 0.6% (0.17 m3 km-1) was recruited through bank erosion. Analyzing the output, 94.3% (40.26 m3 km-1) of LW was transported downstream of the study area, whereas only the 5.7 % (2.43 m3 km-1) of LW was involved in the

  20. Evolution of the landscape along the Clear Creek Corridor, Colorado; urbanization, aggregate mining and reclamation

    Arbogast, Belinda; Knepper, Daniel H.; Melick, Roger A.; Hickman, John

    2002-01-01

    Prime agricultural land along the Clear Creek floodplain, Colorado, attracted settlement in the 1850's but the demand for sand and gravel for 1900's construction initiated a sequence of events that exceeded previous interests and created the modified landscape and urban ecosystem that exists today. The Clear Creek valley corridor offers a landscape filled with a persistent visible and hidden reminder of it's past use. The map sheets illustrate the Clear Creek landscape as a series of compositions, both at the macro view (in the spatial context of urban structure and highways from aerial photographs) and micro view (from the civic scale where landscape features like trees, buildings, and sidewalks are included). The large-scale topographic features, such as mountains and terraces, appear 'changeless' (they do change over geologic time), while Clear Creek has changed from a wide braided stream to a narrow confined stream. Transportation networks (streets and highways) and spiraling population growth in adjacent cities (from approximately 38,000 people in 1880 to over a million in 1999) form two dominant landscape patterns. Mining and wetland/riparian occupy the smallest amount of land use acres compared to urban, transportation, or water reservoir activities in the Clear Creek aggregate reserve study area. Four types of reclaimed pits along Clear Creek were determined: water storage facilities, wildlife/greenbelt space, multiple-purpose reservoirs, and 'hidden scenery.' The latter involves infilling gravel pits (with earth backfill, concrete rubble, or sanitary landfill) and covering the site with light industry or residential housing making the landform hard to detect as a past mine site. Easier to recognize are the strong-edged, rectilinear water reservoirs, reclaimed from off-channel sand and gravel pits that reflect the land survey grid and property boundaries. The general public may not realize softly contoured linear wildlife corridors connecting urban

  1. Geomorphic changes resulting from floods in reconfigured gravel-bed river channels in Colorado, USA

    Elliott, J.G.; Capesius, J.P.

    2009-01-01

    Geomorphic changes in reconfi gured reaches of three Colorado rivers in response to floods in 2005 provide a benchmark for "restoration" assessment. Sedimententrainment potential is expressed as the ratio of the shear stress from the 2 yr, 5 yr, 10 yr, and 2005 floods to the critical shear stress for sediment. Some observed response was explained by the excess of flood shear stress relative to the resisting force of the sediment. Bed-load entrainment in the Uncompahgre River and the North Fork Gunnison River, during 4 and 6 yr floods respectively, resulted in streambed scour, streambed deposition, lateral-bar accretion, and channel migration at various locations. Some constructed boulder and log structures failed because of high rates of bank erosion or bed-material deposition. The Lake Fork showed little or no net change after the 2005 flood; however, this channel had not conveyed floods greater than the 2.5 yr flood since reconfi guration. Channel slope and the 2 yr flood, a surrogate for bankfull discharge, from all three reconfi gured reaches plotted above the Leopold and Wolman channel-pattern threshold in the "braided channel" region, indicating that braiding, rather than a single-thread meandering channel, and midchannel bar formation may be the natural tendency of these gravel-bed reaches. When plotted against a total stream-power and median-sediment-size threshold for the 2 yr flood, however, the Lake Fork plotted in the "single-thread channel" region, the North Fork Gunnison plotted in the " multiplethread" region, and the Uncompahgre River plotted on the threshold. All three rivers plotted in the multiple-thread region for floods of 5 yr recurrence or greater. ?? 2009 Geological Society of America.

  2. The influence of topology on hydraulic conductivity in a sand-and-gravel aquifer

    Morin, Roger H.; LeBlanc, Denis R.; Troutman, Brent M.

    2010-01-01

    A field experiment consisting of geophysical logging and tracer testing was conducted in a single well that penetrated a sand-and-gravel aquifer at the U.S. Geological Survey Toxic Substances Hydrology research site on Cape Cod, Massachusetts. Geophysical logs and flowmeter/pumping measurements were obtained to estimate vertical profiles of porosity ϕ, hydraulic conductivity K, temperature, and bulk electrical conductivity under background, freshwater conditions. Saline-tracer fluid was then injected into the well for 2 h and its radial migration into the surrounding deposits was monitored by recording an electromagnetic-induction log every 10 min. The field data are analyzed and interpreted primarily through the use of Archie's (1942) law to investigate the role of topological factors such as pore geometry and connectivity, and grain size and packing configuration in regulating fluid flow through these coarse-grained materials. The logs reveal no significant correlation between K and ϕ, and imply that groundwater models that link these two properties may not be useful at this site. Rather, it is the distribution and connectivity of the fluid phase as defined by formation factor F, cementation index m, and tortuosity α that primarily control the hydraulic conductivity. Results show that F correlates well with K, thereby indicating that induction logs provide qualitative information on the distribution of hydraulic conductivity. A comparison of α, which incorporates porosity data, with K produces only a slightly better correlation and further emphasizes the weak influence of the bulk value of ϕ on K.

  3. Bedform morphology of salmon spawning areas in a large gravel-bed river

    Hanrahan, Timothy P.

    2007-05-01

    While the importance of river channel morphology to salmon spawning habitat is increasingly recognized, quantitative measures of the relationships between channel morphology and habitat use are lacking. Such quantitative measures are necessary as management and regulatory agencies within the Pacific Northwestern region of the USA, and elsewhere, seek to quantify potential spawning habitat and develop recovery goals for declining salmon populations. The objective of this study was to determine if fall Chinook salmon (Oncorhynchus tshawytscha) spawning areas in the Snake River, Idaho, USA, were correlated with specific bed form types at the pool-riffle scale. A bed form differencing technique was used to objectively quantify the longitudinal riverbed profile into four distinct pool-riffle units that were independent of discharge. The vertical location of thalweg points within these units was quantified with a riffle proximity index. Chinook salmon spawning areas were mapped and correlated with the pool-riffle units through the use of cross-tabulation tables. The results indicate that 84% of fall Chinook salmon spawning areas were correlated with riffles (Chi-square=152.1, df=3, p<0.001), with 53% of those areas located on the upstream side of riffle crests. The majority of Snake River fall Chinook salmon spawning occurred at a vertical location within 80% of the nearest riffle crest elevation. The analyses of bed form morphology will assist regional fish mangers in quantifying existing and potential fall Chinook salmon spawning habitat, and will provide a quantitative framework for evaluating general ecological implications of channel morphology in large gravel-bed rivers.

  4. More than ten million years of hyper-aridity recorded in the Atacama Gravels

    Sun, Tao; Bao, Huiming; Reich, Martin; Hemming, Sidney R.

    2018-04-01

    The Atacama Desert's hyper-aridity is closely linked to the development of world-class copper and nitrate/iodine ores and to regional tectonics and global paleoclimate changes in the Cenozoic era. The timing when the hyper-aridity commenced remains controversial, with proposed ages ranging from Late Oligocene to Pleistocene. In this study, we provide an independent constraint on the initiation of Atacama hyper-aridity utilizing a 100-m deep profile within the Atacama Gravels and underneath porphyry copper deposit in Spence, northern Chile. The overall high concentration of sulfate (up to 10 wt%) and a multimodal distribution of water soluble salt (sulfates, chlorides and nitrates) indicate multiple generations of sedimentation and salt accumulation events under semi-arid to hyper-arid climate conditions. The multiple sulfate isotope compositions (Δ17O, δ18O, δ34S) of the upper section (-15.0 to -34.5 m) are close to those of modern hyperarid surface sulfates, while the lower section (-34.5 to -65 m) displays a depth dependent isotope trend that is best interpreted as marking a period of climate change from semi-arid to hyper-arid. When these data are combined with new chronological 40Ar/39Ar dates obtained from a volcanic ash layer at depth of -28.0 m, our results show that hyper-arid condition in the Atacama Desert was prevailing at least prior to 9.47 Ma and may go back as old as the middle Miocene.

  5. Analytical study on the suitability of using bentonite coated gravel as a landfill liner material

    Roberts, Anel A.; Shimaoka, Takayuki

    2008-01-01

    This study investigates the feasibility of using bentonite coated gravel (BCG) as a liner material for waste landfills. BCG has proven to be a very effective capping material/method for the remediation of contaminated sediments in aquatic environments. The concept of BCG is similar to that of peanuts/almonds covered with chocolate; each aggregate particle has been covered with the clayey material. Laboratory tests were aimed at evaluating regulated and non-regulated factors for liner materials, i.e., permeability and strength. Tests included X-ray diffraction, methylene blue absorption, compaction, free swelling, permeability, 1D consolidation, triaxial compression and cone penetration. The compactive efforts used for this study were the reduced Proctor, standard Proctor, intermediate Proctor, modified Proctor and super modified Proctor. The compactive energy corresponding to each effort, respectively, is as follows: 355.5, 592.3, 1196.3, 2693.3, and 5386.4 kJ/m 3 . Results revealed that even though aggregate content represents 70% of the weight of the material, hydraulic conductivities as low as 6 x 10 -10 cm/s can be achieved when proper compactive efforts are used. Compressibility is very low for this material even at low (or no) compactive efforts. Results also demonstrated how higher compactive efforts can lower the permeability of BCG; however, over-compaction creates fractures in the aggregate core of BCG that could increase permeability. Moreover, higher compactive efforts create higher swelling pressures that could compromise the performance of a barrier constructed using BCG. As a result of this study, moderate compactive efforts, i.e., intermediate Proctor or modified Proctor, are recommended for constructing a BCG barrier. Using moderate compactive efforts, very low hydraulic conductivities, good workability and good trafficability are easily attainable

  6. Data mining for service

    2014-01-01

    Virtually all nontrivial and modern service related problems and systems involve data volumes and types that clearly fall into what is presently meant as "big data", that is, are huge, heterogeneous, complex, distributed, etc. Data mining is a series of processes which include collecting and accumulating data, modeling phenomena, and discovering new information, and it is one of the most important steps to scientific analysis of the processes of services.  Data mining application in services requires a thorough understanding of the characteristics of each service and knowledge of the compatibility of data mining technology within each particular service, rather than knowledge only in calculation speed and prediction accuracy. Varied examples of services provided in this book will help readers understand the relation between services and data mining technology. This book is intended to stimulate interest among researchers and practitioners in the relation between data mining technology and its application to ...

  7. African mining '91

    1991-01-01

    The second 'African Mining' conference was held in June 1991, and followed the first event held in May 1987. That full four-year period was characterized by substantial changes in the political and economic climate of many countries in both hemispheres. The results of many of these changing facets of our industry are described in the papers in African Mining'91. Many of the papers deal with advances in technology, which is the main reason for the meeting. There are 37 papers under the headings general, mining, metallurgy and geology and exploration. Most papers are concerned with gold, copper and mineral mining. One paper concerning uranium mining operations in Namibia is indexed separately. (author)

  8. Argentina : tous les projets | Page 4 | CRDI - Centre de recherches ...

    Région: Argentina, South America, Brazil, Chile, Mexico, North and Central America ... Sujet: WOMEN'S PARTICIPATION, POLITICS, POLITICAL LEADERSHIP, WOMEN'S RIGHTS, GENDER ... Sujet: BIOLOGY, BIODIVERSITY, ECOLOGY.

  9. Argentina : tous les projets | Page 7 | CRDI - Centre de recherches ...

    Sujet: INTERNATIONAL AGREEMENTS, WOMEN'S RIGHTS, LEGISLATION, ACCESS TO ... SERVICES, GENDER DISCRIMINATION, GENDER EQUALITY, Gender ... Région: Argentina, Bangladesh, Brazil, India, Lebanon, Malawi, Viet Nam.

  10. Argentina : tous les projets | Page 8 | CRDI - Centre de recherches ...

    ... INNOVATIONS, INFORMATION TECHNOLOGY, Internet, TEACHING AIDS, ... Région: Argentina, South America, Brazil, Chile, Colombia, Mexico, North and ... Sujet: SOCIAL PARTICIPATION, Civil society, HEALTH SYSTEM, Evaluation.

  11. Mining-induced earthquakes monitored during pit closure in the Midlothian Coalfield

    Redmayne, D.W.; Richards, J.A.; Wild, P.W. [British Geological Survey, Edinburgh (United Kingdom). Global Seismology and Geomagnetism Group

    1998-06-01

    The British Geological Survey installed a seismometer network to monitor earthquakes around Rosslyn Chapel in the Midlothian Coalfield from November 1987 until January 1990. Accurate locations were obtained for 247 events and a close spatial and temporal association with concurrent coal mining, with a rapid decay of earthquake activity following pit closure, was demonstrated, indicating a mining-induced cause. Residual stress from past mining appears to have been an important factor in generating seismicity, and observations indicate that limiting the width of the workings or rate of extraction may significantly reduce or eliminate mining-induced earthquake activity. A frequency-magnitude analysis indicates a relatively high abundance of small events in this coalfield area. The maximum magnitude of a mining-induced earthquake likely to have been experienced during the life of the coalfield (maximum credible magnitude) was 3.0 M-L, although an extreme event (maximum possible magnitude) as large as 3.4 M-L was remotely possible. Significant seismic amplification was observed at Rosslyn Chapel, which is founded on sand and gravel, compared with a nearby bedrock site. As a consequence, relatively small magnitude events caused high, and occasionally damaging, seismic intensities at the chapel.

  12. LAS ESPECIES ARGENTINAS DEL GENERO SICYOS (CUCURBITACEAE.

    Raúl Martínez Crovetto

    1964-01-01

    Full Text Available El autor estudia las especies del género Sicyos que viven dentro del territorio de la República Argentina; señalando que hasta el presente se han hallado seis. Luego de una diagnosis del género, suministra una clave, descripciones y figuras de cada una de ellas, a fin de facilitar su reconocimiento. Las especies estudiadas son S. malvifolius Griseb., S. polyacanthus Cogn., S. Odanellii Mart.-Crov., S. Kunthii Cogn. (nuevo habitante para la flora argentina, S. Warmingii Cogn, S. Warmingii Cogn. var. longispina Mart.-Crov. (nueva variedad y S. ignarus Mart.-Crov. (especie nueva para la ciencia.

  13. La migracion internacional en Argentina hacia 2010

    Laura Calvelo

    Full Text Available El artículo presenta los principales lineamientos de la migración internacional en Argentina hacia el año 2010, con detenimiento en el período 2000-2010. En el caso de la inmigración no nativa se basa en información de los censos nacionales de población 2001 y 2010. En el caso de la migración internacional de la población nativa de Argentina el análisis se sustenta en información de censos extranjeros hasta la ronda 2000 y en otras fuentes de datos de los principales países de destino hasta 2010 (Estados Unidos y España.

  14. Measurements of atmospheric fallout in Argentina

    Canoba, A.C.; Lopez, F.O.; Bruno, H.A.

    1998-01-01

    With the purpose of studying the radioactive fallout present in Argentina from atmospheric nuclear explosions tests that have been conducted recently, an environmental monitoring program, outside the influence of nuclear facilities of Argentina, was undertaken during 1996 and 1997. The levels of Cs-137 and Sr-90 were analysed in samples of air, deposited material (rainwater), milk, an average meal of a standard man and food. During this period, a total of 630 radiochemical analysis were performed on 325 samples of the different matrices described. The concentration levels of the radionuclides analysed in the different environmental matrices are presented and are compared with the values obtained in the environmental monitoring program done during the period 1960-1981. (author) [es

  15. Spent fuel management of NPPs in Argentina

    Alvarez, D.E.; Lee Gonzalez, H.M.

    2010-01-01

    There are two Nuclear Power Plants in operation in Argentina: 'Atucha I' (unique PHWR design) in operation since 1974, and 'Embalse' (typical Candu reactor) which started operation in 1984. Both NPPs are operated by 'Nucleoelectrica Argentina S.A' which is responsible for the management and interim storage of spent fuel till the end of the operative life of the plants. A third NPP, 'Atucha II' is under construction, with a similar design of Atucha I. The legislative framework establishes that after final shutdown of a NPP the spent fuel will be transferred to the 'National Atomic Energy Commission', which is also responsible for the decommissioning of the Plants. In Atucha I, the spent fuel is stored underwater, until another option is implemented meanwhile in Embalse the spent fuel is stored during six years in pools and then it is moved to a dry storage. A decision about the fuel cycle back-end strategy will be taken before year 2030. (authors)

  16. Cultural Diversity: "Reports from Brazil and Argentina"

    Célia Regina Rossi

    2007-06-01

    Full Text Available This article tells two experiences of projects carried through in schools of basic education whose thematic it was the work with the cultural diversity, the valuation of other cultures and reflections on the proper culture The work was carried through in two schools: one in the state of São Paulo, the city of Rio Claro where as the thematic one worked was the Hip-Hop and cultural manifestations local Brazilians the second in the capital of a Argentina province, in the city of Paraná where it worked the contact and the relation enter the cultural manifestations of Brazil and Argentina The central objective of this work was to think ways that could lead to the construction of a school that it considered the differences and the learning that happens when these (the differences they are in relation.

  17. Argentina and Brazil: an evolving nuclear relationship

    Redick, J.R.

    1990-01-01

    Argentina and Brazil have Latin America's most advanced nuclear research and power programs. Both nations reject the Non-Proliferation Treaty (NPT), and have not formally embraced the Tlatelolco Treaty creating a regional nuclear-weapon-free zone. Disturbing ambiguities persist regarding certain indigenous nuclear facilities and growing nuclear submarine and missile capabilities. For these, and other reasons, the two nations are widely considered potential nuclear weapon states. However both nations have been active supporters of the International Atomic Energy Agency (IAEA) and have, in recent years, assumed a generally responsible position in regard to their own nuclear export activities (requiring IAEA safeguards). Most important, however, has been the advent of bilateral nuclear cooperation. This paper considers the evolving nuclear relationship in the context of recent and dramatic political change in Argentina and Brazil. It discusses current political and nuclear developments and the prospects for maintaining and expanding present bilateral cooperation into an effective non-proliferation arrangement. (author)

  18. Rocky Mountain spotted fever in Argentina.

    Paddock, Christopher D; Fernandez, Susana; Echenique, Gustavo A; Sumner, John W; Reeves, Will K; Zaki, Sherif R; Remondegui, Carlos E

    2008-04-01

    We describe the first molecular confirmation of Rickettsia rickettsii, the cause of Rocky Mountain spotted fever (RMSF), from a tick vector, Amblyomma cajennense, and from a cluster of fatal spotted fever cases in Argentina. Questing A. cajennense ticks were collected at or near sites of presumed or confirmed cases of spotted fever rickettsiosis in Jujuy Province and evaluated by polymerase chain reaction assays for spotted fever group rickettsiae. DNA of R. rickettsii was amplified from a pool of A. cajennense ticks and from tissues of one of four patients who died during 2003-2004 after illnesses characterized by high fever, severe headache, myalgias, and petechial rash. The diagnosis of spotted fever rickettsiosis was confirmed in the other patients by indirect immunofluorescence antibody and immunohistochemical staining techniques. These findings show the existence of RMSF in Argentina and emphasize the need for clinicians throughout the Americas to consider RMSF in patients with febrile rash illnesses.

  19. Investment in Renewable Energies in Argentina

    Marina Recalde

    2017-01-01

    This article analyzes how the enabling conditions of the energy policy of a developing country such as Argentina, are crucial for the deployment of renewable energy investments. The conclusions highlights that the low institutional quality of the country shapes enabling conditions and reduce effect of the instruments of the energy policy, dropping incentives for investment in renewable technologies in the country. Therefore, in order to promote renewable technologies investments efficiently, ...

  20. Investment in Renewable Energies in Argentina

    Marina Recalde

    2017-05-01

    Full Text Available This article analyzes how the enabling conditions of the energy policy of a developing country such as Argentina, are crucial for the deployment of renewable energy investments. The conclusions highlights that the low institutional quality of the country shapes enabling conditions and reduce effect of the instruments of the energy policy, dropping incentives for investment in renewable technologies in the country. Therefore, in order to promote renewable technologies investments efficiently, the institutional framework of countries must be seriously improved.

  1. Area Handbook Series: Argentina: A Country Study

    1985-08-01

    votes after a campaign that emphasized firm opposition to the military government and verbal attacks on the trade union leadership of the PJ...legal pro- cedures that were designed especially for these cases. The trials were open to the public, evidence would be taken verbal - ly instead of...1981,144-45. Terrera, Guillermo Alfredo. Geopolitica Argentina: Poblacion, fronteras, comunicaciones , antropologia. Buenos Aires: Edi- torial Plus

  2. Memories of the armed struggle in Argentina

    Laura Margarita Pasquali

    2013-06-01

    Full Text Available This article presents and develops some of the edges on working of the guerrilla that emerge in the memories of the former militants of the armed organizations in Argentina. Beginig from this journey we will have access to the registration that one has presently on it, which will allows us to establish part of the subjective environment of the moment, the main characters consideration of the activism and their significance in the general context of the militancy.

  3. Burden of Serious Fungal Infections in Argentina

    Fernando O. Riera

    2018-04-01

    Full Text Available The number of fungal infections at any given time in Argentina is not known. Here we estimate the burden of serious fungal infections in Argentina for the first time. Specific population statistics were searched from multiple sources, local literature was identified, and estimates made. Some additional data were sourced from the Ministry of Health, the Global Initiative for Asthma (GINA program, and national haematology and transplant societies. Argentina has a population of 43.8 million, with 25% of this total being children under 15 years. The predicted candidemia annual incidence is 2193 cases, with 50% occurring in the ICU. At a 6% prevalence rate, an estimated 593,695 women suffer from recurrent vulvovaginal candidiasis. Invasive aspergillosis is relatively common because of high smoking and chronic obstructive pulmonary disease (COPD rates, with 268 cases in immunocompromised patients and another 1938 in the 168,000 COPD patients admitted to hospital. Asthma is also common, affecting 14% of adults, and so allergic bronchopulmonary aspergillosis (ABPA and severe asthma with fungal sensitization (SAFS are major problems. An estimated 432 cases of cryptococcal meningitis (CM—90% of them in AIDS patients—and 1177 cases of Pneumocystis pneumonia (PCP occur each year. The estimated annual case number of disseminated histoplasmosis is 404 in AIDS patients, almost as frequent as CM. Paracoccidioidomycosis annual incidence is estimated at 219, and coccidioidomycosis at 16 cases. At least 881,023 people (>2.01% in Argentina are affected by a serious fungal disease annually, with considerable morbidity and mortality.

  4. The "Private School Advantage" in Argentina

    Gustavo E. Fischman

    2001-08-01

    Full Text Available Local actors' perceptions of curricular and management changes in two private schools and one neighboring public secondary school in the city of Buenos Aires, Argentina, are analyzed. An exploration was conducted of how, within an ideologically and politically pro-reform context and a widespread acceptance of the "private school advantage," principals, teachers, and students in these schools evaluated the changes (or lack of them in management, teaching, and curriculum orientations of the secondary education sector.

  5. Where is Argentina going in geothermal energy

    Mange, J

    1977-01-01

    A brief review is given of geothermal exploration and development in Argentina. Methodical efforts to inventory the geothermal resources of the country were begun in 1974. The Commission set itself the task of locating the geothermal anomalies and then selecting particular anomalies for intensive exploration in order to confirm or discard the possibilities of exploiting the resource. The known principal anomalies are listed and the two selected for intensive exploration are indicated. (JSR)

  6. The Andean Swallow (Orochelidon andecola) in Argentina

    Mazar Barnett, Juan; Pugnali, Germán D.; Pearman Morrison, Mark; Bodrati, Alejandro; Moschione, Flavio; Clark, Ricardo; Roesler, Carlos Ignacio; Monteleone, Diego; Casañas, Hernán; Burgos Gallardo, Freddy; Segovia, José; Pagano, Luis; Povedano, Hernán; Areta, Juan Ignacio

    2016-01-01

    During ornithological studies in the provinces of Jujuy, Salta, and San Juan, we recorded the Andean Swallow Orochelidon andecola at 40 localities. These are the first records in Argentina, and also represent the southernmost for the species. Some of these localities are up to 1500 m lower than the previously known elevational limit (now 800 masl), and up to 1100 km southwards. This is a relatively poorly known swallow, and we present novel natural history data. We found evidence of breeding ...

  7. The "Private School Advantage" in Argentina

    Gustavo E. Fischman

    2001-01-01

    Local actors' perceptions of curricular and management changes in two private schools and one neighboring public secondary school in the city of Buenos Aires, Argentina, are analyzed. An exploration was conducted of how, within an ideologically and politically pro-reform context and a widespread acceptance of the "private school advantage," principals, teachers, and students in these schools evaluated the changes (or lack of them) in management, teaching, and curriculum orientations of the se...

  8. About the Triple A. Argentina 1973 - 1976

    Rostica, Julieta

    2011-01-01

    On May 25, 1973, Peronism returned to govern Argentina after about two decades of prohibition and political persecution. After its establishment, certain crimes began to be signed with “AAA”. The Triple A adopted the particularity of disappearing with the coup on March 24 1976. Why could this organization only exist in a democracy erected in the middle of two military dictatorships? Why did it exist during the very wished Peronist government? The article offers an approach to the Triple A, th...

  9. Radioecological challenges for mining

    Vesterbacka, P.; Ikaeheimonen, T.K.; Solatie, D. [Radiation and Nuclear Safety Authority (Finland)

    2014-07-01

    In Finland, mining became popular in the mid-1990's when the mining amendments to the law made the mining activities easier for foreign companies. Also the price of the minerals rose and mining in Finland became economically profitable. Expanding mining industry brought new challenges to radiation safety aspect since radioactive substances occur in nearly all minerals. In Finnish soil and bedrock the average crystal abundance of uranium and thorium are 2.8 ppm and 10 ppm, respectively. It cannot be predicted beforehand how radionuclides behave in the mining processes which why they need to be taken into account in mining activities. Radiation and Nuclear Safety Authority (STUK) has given a national guide ST 12.1 based on the Finnish Radiation Act. The guide sets the limits for radiation doses to the public also from mining activities. In general, no measures to limit the radiation exposure are needed, if the dose from the operation liable to cause exposure to natural radiation is no greater than 0.1 mSv per year above the natural background radiation dose. If the exposure of the public may be higher than 0.1 mSv per year, the responsible party must provide STUK a plan describing the measures by which the radiation exposure is to be kept as low as is reasonably achievable. In that case the mining company responsible company has to make a radiological baseline study. The baseline study must focus on the environment that the mining activities may impact. The study describes the occurrence of natural radioactivity in the environment before any mining activities are started. The baseline study lasts usually for two to three years in natural circumstances. Based on the baseline study measurements, detailed information of the existing levels of radioactivity in the environment can be attained. Once the mining activities begin, it is important that the limits are set for the wastewater discharges to the environment and environmental surveillance in the vicinity of

  10. Acute intermittent porphyria in Argentina: an update.

    Cerbino, Gabriela Nora; Gerez, Esther Noemí; Varela, Laura Sabina; Melito, Viviana Alicia; Parera, Victoria Estela; Batlle, Alcira; Rossetti, María Victoria

    2015-01-01

    Porphyrias are a group of metabolic diseases that arise from deficiencies in the heme biosynthetic pathway. A partial deficiency in hydroxymethylbilane synthase (HMBS) produces a hepatic disorder named Acute Intermittent Porphyria (AIP); the acute porphyria is more frequent in Argentina. In this paper we review the results obtained for 101 Argentinean AIP families and 6 AIP families from foreign neighbour countries studied at molecular level at Centro de Investigaciones sobre Porfirinas y Porfirias (CIPYP). Thirty-five different mutations were found, of which 14 were described for the first time in our population. The most prevalent type of mutations was the missense mutations (43%) followed by splice defects (26%) and small deletions (20%). An odd case of a double heterozygous presentation of AIP in a foreign family from Paraguay is discussed. Moreover, it can be noted that 38 new families were found carrying the most frequent mutation in Argentina (p.G111R), increasing to 55.66% the prevalence of this genetic change in our population and adding further support to our previous hypothesis of a founder effect for this mutation in Argentina. Identification of patients with an overt AIP is important because treatment depends on an accurate diagnosis, but more critical is the identification of asymptomatic relatives to avoid acute attacks which may progress to death.

  11. La letteratura italiana tradotta in Argentina

    Silvia Cattoni

    2017-11-01

    Full Text Available In due secoli di storia della letteratura argentina, lo sviluppo della letteratura italiana tradotta è in stretto rapporto con i propositi pedagogici o estetici determinati dal contesto culturale dei diversi momenti storici. In linea di massima, è possibile affermare che, dalla conformazione dello Stato nazionale e durante i primi decenni del XX secolo, la traduzione letteraria mirava ad ampliare l’orizzonte culturale di un lettore che si consolidava al ritmo della fiammante nazione. Nelle fasi successive e in stretto rapporto con la politica culturale portata avanti da Victoria Ocampo a partire dal 1931 tramite la rivista Sur e il suo posteriore progetto editoriale, la traduzione è stata soprattutto una pratica di scrittura che ebbe un’influenza decisiva nell’ordito della letteratura nazionale favorendo il suo rinnovo e incentivando le versioni di traduttori argentini. Fu questa un’apertura che favorì, durante la seconda metà del secolo, nel contesto della ricezione della letteratura universale, l’ingresso della letteratura italiana in Argentina. Il presente lavoro tratta in maniera sistematica, ma provvisoria, il panorama della letteratura italiana tradotta in Argentina. Lo scopo principale comporta il registro dei momenti più fecondi e l’interpretazione degli esiti ottenuti nei confronti della traduzione nel sistema letterario nazionale.

  12. Ideate about building green mine of uranium mining and metallurgy

    Shi Zuyuan

    2012-01-01

    Analysing the current situation of uranium mining and metallurgy; Setting up goals for green uranium mining and metallurgy, its fundamental conditions, Contents and measures. Putting forward an idea to combine green uranium mining and metallurgy with the state target for green mining, and keeping its own characteristics. (author)

  13. Mining and mining authorities in Saarland 2016. Mining economy, mining technology, occupational safety, environmental protection, statistics, mining authority activities. Annual report

    2016-01-01

    The annual report of the Saarland Upper Mining Authority provides an insight into the activities of mining authorities. Especially, the development of the black coal mining, safety and technology of mining as well as the correlation between mining and environment are stressed.

  14. The last twenty years of the IAEA technical cooperation on the uranium production cycle in Argentina

    Lopez, L.

    2014-01-01

    Since 1993, the National Atomic Energy Commission (Argentina) has been involved in several IAEA Technical Cooperation Projects at interregional, regional and national levels, covering different aspects of the uranium production cycle. The TC referred projects can be listed as follows: - INT 2/015 “Supporting Uranium Exploration Resource Augmentation and Production Using Advanced Techniques” (2012 – Present). - RLA 3/006 - 010 “Upgrading of Uranium Exploration, Exploitation and Yellowcake Production Techniques taking Environmental Problems into Account” (2007 - Present). - ARG 2/014 “Development and Strengthening of the Uranium Mining Cycle Human Resources” (2012 – Present). - ARG 3/012 - 014 "Geology favourability, production feasibility and environmental impact assessment of uranium deposits exploitable by the in situ leaching technology (ISL)'' (2007 - Present). - ARG 3/009 “Development and use of biological techniques for uranium production (ARG 3/009)” (2003 - 2006). - ARG 3/008 “Prospection of uranium and other elements using gamma-ray spectrometry surveys” (2001 – 2005). - ARG 3/007 “Uranium Favorability and Exploration in Argentina” (1993 - 1997). It can be considered that the role of the technological transfer by the IAEA has been highly relevant for increasing the capability of strategically plan and more efficiently carry out the uranium production cycle projects in Argentina. (author)

  15. Environmental monitoring data review of a uranium ore processing facility in Argentina

    Bonetto, J.

    2014-01-01

    An uranium ore processing facility in the province of Mendoza (Argentina) that has produced uranium concentrate from 1954 to 1986 is currently undergoing the last steps of environmental restoration. The operator has been performing post-closure environmental monitoring since 1986, while the Nuclear Regulatory Authority (ARN) has been carrying out its own independent radiological environmental monitoring for verification purposes since its creation, in 1995. A detailed revision of ARN´s monitoring plan for uranium mining and milling facilities has been undergoing since 2013, starting with this particular site. Results obtained from long-time sampling locations (some of them currently unused) have been analyzed and potentially new sampling points have been studied and proposed. In this paper, some statistical analysis and comparison of sampling-points’ datasets are presented (specifically uranium and radium concentration in groundwater, surface water and sediments) with conclusions pertaining to their keeping or discarding as sampling points in future monitoring plans. (author)

  16. Applying a small NPP in the Argentine mining industry

    Barrientos, C.J.; Masriera, N.A.

    1998-01-01

    The CAREM 25 reactor project is a small PWR nuclear power plant of 27 MWe, based on advanced concepts: a self-pressurized integral primary with natural convection of the coolant and a more simple and reliable general design. The CAREM concept has many advantages as a power generator in small electrical grids. Besides, there are some non-electrical applications under consideration, since a co-generation scheme seems very interesting from the economical point of view. In this category two alternatives have been considered: a standard desalination facility and a process plant in the mining industry. In this paper, a conceptual analysis of the second alternative is presented. Mining is a branch of the domestic industry that has shown a remarkable growth in the past three years mainly due to a steady inflow of foreign investments (about two billion dollars for that period). And one of the most attractive markets is in the extraction and manufacturing of non-ferrous minerals, coming from deposits in the northwest of Argentina: sodium sulfate, lithium salts, and boron compounds. Nevertheless it faces an unsolved problem in the energy high prices due to the fact that the production sites are located in remote areas where the only achievable energy source is the transportation of fuel oil. In this scenario, a small NPP may be a competitive source of process heat and electricity, with enough autonomy to uncouple fuel requirements from production strategies. The present study analyses the possible application of the CAREM concept in the non-ferrous mining industry of the Northwest of Argentina, considering a co-generation scheme. The main results of this analysis and the inherent advantages of the approach, show that the alternative may be feasible both from the technical and the economical points of view. (author)

  17. Mining toward the year 2000

    Anon.

    1981-01-01

    Mining in South Africa to this present day has not been a case of dramatic development, rather a steady technical progress, assisted by a rising product market price. Prominent men in the mining industry look at the future in terms of that logical development. Coverage is given to gold, mine unionization, coal, rock bursts, ventilation, uranium and ocean mining

  18. Open pit mining of uranium

    Wood, J.T.

    1977-01-01

    The Jackpile--Paquate Mines of the Anaconda Company are on the Laguna Indian Reservation midway between Grants and Albuquerque, New Mexico. The open pit mining of uranium ore at those mines is conducted in three separate operations (stripping, mining, and ore haul)

  19. Australian uranium mining policy

    Fisk, B.

    1985-01-01

    Australian government policy is explained in terms of adherence to the Non-Proliferation Treaty. Two alleged uncertainties are discussed: the future of Australian mining industry as a whole -on which it is said that Australian uranium mines will continue to be developed; and detailed commercial policy of the Australian government - on which it is suggested that the three-mines policy of limited expansion of the industry would continue. Various aspects of policy, applying the principles of the NPT, are listed. (U.K.)

  20. Mining on the Mesa

    Sprouls, M.W.

    1994-10-01

    Peabody Western Coal Co. is the owner of Black Mesa and Kayenta coal opencast mines, both sited on Hopi and Navajo lands. 93% of the employees are native American, mostly Navajo. Kayenta is the larger and extracts coal with draglines. Sulphur content is high so the coal has to be analyzed and carefully blended before use. Black Mesa also uses draglines, here quality control is not as important as it is at Kayenta. Coal is transported to power stations using slurry pipelines. Both mines are heavily involved in land reclamation, leaving a landscape that makes better grazing than it did before mining. 2 figs.

  1. A Water Resources Management Model to Evaluate Climate Change Impacts in North-Patagonia, Argentina

    Bucciarelli, L. F.; Losano, F. T.; Marizza, M.; Cello, P.; Forni, L.; Young, C. A.; Girardin, L. O.; Nadal, G.; Lallana, F.; Godoy, S.; Vallejos, R.

    2014-12-01

    Most recently developed climate scenarios indicate a potential future increase in water stress in the region of Comahue, located in the North-Patagonia, Argentina. This region covers about 140,000 km2 where the Limay River and the Neuquén River converge into the Negro River, constituting the largest integrated basins in Argentina providing various uses of water resources: a) hydropower generation, contributing 15% of the national electricity market; b) fruit-horticultural products for local markets and export; c) human and industrial water supply; d) mining and oil exploitation, including Vaca Muerta, second world largest reserves of shale gas and fourth world largest reserves of shale-oil. The span of multiple jurisdictions and the convergence of various uses of water resources are a challenge for integrated understanding of economically and politically driven resource use activities on the natural system. The impacts of climate change on the system could lead to water resource conflicts between the different political actors and stakeholders. This paper presents the results of a hydrological simulation of the Limay river and Neuquén river basins using WEAP (Water Evaluation and Planning) considering the operation of artificial reservoirs located downstream at a monthly time step. This study aims to support policy makers via integrated tools for water-energy planning under climate uncertainties, and to facilitate the formulation of water policy-related actions for future water stress adaptation. The value of the integrated resource use model is that it can support local policy makers understand the implications of resource use trade-offs under a changing climate: 1) water availability to meet future growing demand for irrigated areas; 2) water supply for hydropower production; 3) increasing demand of water for mining and extraction of unconventional oil; 4) potential resource use conflicts and impacts on vulnerable populations.

  2. Microbial community variation and functions to excess sludge reduction in a novel gravel contact oxidation reactor

    Lin Shanshan; Jin, Y.; Fu, L. [School of Urban and Environmental Science, Northeast Normal University, Changchun (China); Quan, C. [Jilin University, College of medicine, Changchun (China); Yang, Y.S., E-mail: yangy6@cf.ac.uk [Cardiff University, School of Earth and Ocean Sciences, Cardiff CF10 3YE (United Kingdom)

    2009-06-15

    Excess biomass produced within the degradation processes of organic pollutants is creating environmental challenges. The gravel contact oxidation reactor (GCOR) filled with crushed stone globular aggregates as carriers, has been demonstrated capable of reducing the excess sludge effectively in some pilot and small-scale engineering studies. In order to evaluate the variation and structure of the microbial community and their functions to excess sludge reduction in GCOR, a conventional activated sludge reactor (ASR) was studied as a comparison. The 16S rDNA library of the universal bacteria was constructed, Shannon's diversity index (H) and Species evenness (E) were calculated with distance-based operational taxonomic unit and richness (DOTUR) for microbial diversity. Real-time quantity PCR and optical microscope were used for absolute bacterial DNA concentration and eukarya identification, respectively. Meanwhile, the suspended solid index in GCOR and ASR was detected for assessing the excess sludge production. The results indicated that the most abundant bacteria in GCOR were those related to the {beta}-Proteobacteria group, then {gamma}-Proteobacteria and to Cytophaga-Flexibacter-Bacteriode (CFB). In the ASR samples major bacteria were in the closest match with {gamma}-Proteobacteria, then {beta}-Proteobacteria and CFB. Shannon's index (H) was higher (3.41) for diversity of bacteria extracted from the carrier samples in GCOR than that (2.71) from the sludge sample in ASR. Species evenness (E) for the isolates from GCOR and ASR samples was 0.97 and 0.96, respectively. Comparison of the universal bacteria population in GCOR and ASR shows that the total bacterial DNA concentration on the GCOR carriers were 8.98 x 10{sup 5} {mu}g/{mu}l, twice that in ASR of 4.67 x 10{sup 5} {mu}g/{mu}l under normal operation of two reactors. But the MLSS in GCOR was only 4.5 mg/L, 25 times less than that in ASR of 115.4 mg/L. The most representative eukarya were protozoa

  3. Modeling wood dynamics, jam formation, and sediment storage in a gravel-bed stream

    Eaton, B. C.; Hassan, M. A.; Davidson, S. L.

    2012-12-01

    In small and intermediate sized streams, the interaction between wood and bed material transport often determines the nature of the physical habitat, which in turn influences the health of the stream's ecosystem. We present a stochastic model that can be used to simulate the effects on physical habitat of forest fires, climate change, and other environmental disturbances that alter wood recruitment. The model predicts large wood (LW) loads in a stream as well as the volume of sediment stored by the wood; while it is parameterized to describe gravel bed streams similar to a well-studied field prototype, Fishtrap Creek, British Columbia, it can be calibrated to other systems as well. In the model, LW pieces are produced and modified over time as a result of random tree-fall, LW breakage, LW movement, and piece interaction to form LW jams. Each LW piece traps a portion of the annual bed material transport entering the reach and releases the stored sediment when the LW piece is entrained and moved. The equations governing sediment storage are based on a set of flume experiments also scaled to the field prototype. The model predicts wood loads ranging from 70 m3/ha to more than 300 m3/ha, with a mean value of 178 m3/ha: both the range and the mean value are consistent with field data from streams with similar riparian forest types and climate. The model also predicts an LW jam spacing that is consistent with field data. Furthermore, our modeling results demonstrate that the high spatial and temporal variability in sediment storage, sediment transport, and channel morphology associated with LW-dominated streams occurs only when LW pieces interact and form jams. Model runs that do not include jam formation are much less variable. These results suggest that river restoration efforts using engineered LW pieces that are fixed in place and not permitted to interact will be less successful at restoring the geomorphic processes responsible for producing diverse, productive

  4. Microbial community variation and functions to excess sludge reduction in a novel gravel contact oxidation reactor

    Lin Shanshan; Jin, Y.; Fu, L.; Quan, C.; Yang, Y.S.

    2009-01-01

    Excess biomass produced within the degradation processes of organic pollutants is creating environmental challenges. The gravel contact oxidation reactor (GCOR) filled with crushed stone globular aggregates as carriers, has been demonstrated capable of reducing the excess sludge effectively in some pilot and small-scale engineering studies. In order to evaluate the variation and structure of the microbial community and their functions to excess sludge reduction in GCOR, a conventional activated sludge reactor (ASR) was studied as a comparison. The 16S rDNA library of the universal bacteria was constructed, Shannon's diversity index (H) and Species evenness (E) were calculated with distance-based operational taxonomic unit and richness (DOTUR) for microbial diversity. Real-time quantity PCR and optical microscope were used for absolute bacterial DNA concentration and eukarya identification, respectively. Meanwhile, the suspended solid index in GCOR and ASR was detected for assessing the excess sludge production. The results indicated that the most abundant bacteria in GCOR were those related to the β-Proteobacteria group, then γ-Proteobacteria and to Cytophaga-Flexibacter-Bacteriode (CFB). In the ASR samples major bacteria were in the closest match with γ-Proteobacteria, then β-Proteobacteria and CFB. Shannon's index (H) was higher (3.41) for diversity of bacteria extracted from the carrier samples in GCOR than that (2.71) from the sludge sample in ASR. Species evenness (E) for the isolates from GCOR and ASR samples was 0.97 and 0.96, respectively. Comparison of the universal bacteria population in GCOR and ASR shows that the total bacterial DNA concentration on the GCOR carriers were 8.98 x 10 5 μg/μl, twice that in ASR of 4.67 x 10 5 μg/μl under normal operation of two reactors. But the MLSS in GCOR was only 4.5 mg/L, 25 times less than that in ASR of 115.4 mg/L. The most representative eukarya were protozoa both in GCOR (15 no. per 20 ml) and in ASR (15

  5. Total Dissolved Gas Monitoring in Chum Salmon Spawning Gravels Below Bonneville Dam

    Arntzen, Evan V.; Geist, David R.; Panther, Jennifer L.; Dawley, Earl

    2007-01-30

    At the request of the U.S. Army Corps of Engineers (Portland District), Pacific Northwest National Laboratory (PNNL) conducted research to determine whether total dissolved gas concentrations are elevated in chum salmon redds during spring spill operations at Bonneville Dam. The study involved monitoring the total dissolved gas levels at egg pocket depth and in the river at two chum salmon spawning locations downstream from Bonneville Dam. Dissolved atmospheric gas supersaturation generated by spill from Bonneville Dam may diminish survival of chum (Oncorhynchus keta) salmon when sac fry are still present in the gravel downstream from Bonneville Dam. However, no previous work has been conducted to determine whether total dissolved gas (TDG) levels are elevated during spring spill operations within incubation habitats. The guidance used by hydropower system managers to provide protection for pre-emergent chum salmon fry has been to limit TDG to 105% after allowing for depth compensation. A previous literature review completed in early 2006 shows that TDG levels as low as 103% have been documented to cause mortality in sac fry. Our study measured TDG in the incubation environment to evaluate whether these levels were exceeded during spring spill operations. Total dissolved gas levels were measured within chum salmon spawning areas near Ives Island and Multnomah Falls on the Columbia River. Water quality sensors screened at egg pocket depth and to the river were installed at both sites. At each location, we also measured dissolved oxygen, temperature, specific conductance, and water depth to assist with the interpretation of TDG results. Total dissolved gas was depth-compensated to determine when levels were high enough to potentially affect sac fry. This report provides detailed descriptions of the two study sites downstream of Bonneville Dam, as well as the equipment and procedures employed to monitor the TDG levels at the study sites. Results of the monitoring at

  6. Suitability of parametric models to describe the hydraulic properties of an unsaturated coarse sand and gravel

    Mace, Andy; Rudolph, David L.; Kachanoski , R. Gary

    1998-01-01

    The performance of parametric models used to describe soil water retention (SWR) properties and predict unsaturated hydraulic conductivity (K) as a function of volumetric water content (θ) is examined using SWR and K(θ) data for coarse sand and gravel sediments. Six 70 cm long, 10 cm diameter cores of glacial outwash were instrumented at eight depths with porous cup ten-siometers and time domain reflectometry probes to measure soil water pressure head (h) and θ, respectively, for seven unsaturated and one saturated steady-state flow conditions. Forty-two θ(h) and K(θ) relationships were measured from the infiltration tests on the cores. Of the four SWR models compared in the analysis, the van Genuchten (1980) equation with parameters m and n restricted according to the Mualem (m = 1 - 1/n) criterion is best suited to describe the θ(h) relationships. The accuracy of two models that predict K(θ) using parameter values derived from the SWR models was also evaluated. The model developed by van Genuchten (1980) based on the theoretical expression of Mualem (1976) predicted K(θ) more accurately than the van Genuchten (1980) model based on the theory of Burdine (1953). A sensitivity analysis shows that more accurate predictions of K(θ) are achieved using SWR model parameters derived with residual water content (θr) specified according to independent measurements of θ at values of h where θ/h ∼ 0 rather than model-fit θr values. The accuracy of the model K(θ) function improves markedly when at least one value of unsaturated K is used to scale the K(θ) function predicted using the saturated K. The results of this investigation indicate that the hydraulic properties of coarse-grained sediments can be accurately described using the parametric models. In addition, data collection efforts should focus on measuring at least one value of unsaturated hydraulic conductivity and as complete a set of SWR data as possible, particularly in the dry range.

  7. Historical coseismic surface deformation of fluvial gravel deposits, Schafberg fault, Lower Rhine Graben, Germany

    Kübler, Simon; Friedrich, Anke M.; Gold, Ryan D.; Strecker, Manfred R.

    2018-03-01

    Intraplate earthquakes pose a significant seismic hazard in densely populated rift systems like the Lower Rhine Graben in Central Europe. While the locations of most faults in this region are well known, constraints on their seismogenic potential and earthquake recurrence are limited. In particular, the Holocene deformation history of active faults remains enigmatic. In an exposure excavated across the Schafberg fault in the southwestern Lower Rhine Graben, south of Untermaubach, in the epicentral region of the 1756 Düren earthquake ( M L 6.2), we mapped a complex deformation zone in Holocene fluvial sediments. We document evidence for at least one paleoearthquake that resulted in vertical surface displacement of 1.2 ± 0.2 m. The most recent earthquake is constrained to have occurred after 815 AD, and we have modeled three possible earthquake scenarios constraining the timing of the latest event. Coseismic deformation is characterized by vertical offset of sedimentary contacts distributed over a 10-m-wide central damage zone. Faults were identified where they fracture and offset pebbles in the vertically displaced gravel layers and fracture orientation is consistent with the orientation of the Schafberg fault. This study provides the first constraint on the most recent surface-rupturing earthquake on the Schafberg fault. We cannot rule out that this fault acted as the source of the 1756 Düren earthquake. Our study emphasizes the importance of, and the need for, paleoseismic studies in this and other intracontinental regions, in particular on faults with subtle geomorphic expression that would not typically be recognized as being potentially seismically active. Our study documents textural features in unconsolidated sediment that formed in response to coseismic rupturing of the underlying bedrock fault. We suggest that these features, e.g., abundant oriented transgranular fractures in their context, should be added to the list of criteria used to identify a fault

  8. An outline of the application of an environmental management system to the PRAMU (Uranium Mining Environmental Restitution Project)

    Smetniansky de De Grande, Nelida; Avila Cadena, Guadalberto; Cardozo, Damian

    2000-01-01

    In Argentina the National Atomic Energy Commission (CNEA) has the responsibility to restore uranium mining facilities, when milling operations have been shut down. To carry out this clean up actions CNEA created the Project for Uranium Mining Environmental Restoration (PRAMU in Spanish). To take into account the environmental aspects of the restoration activities, the PRAMU includes in its management an Environmental Management System (SGA in Spanish), which is of central importance in determining the environmental policy, objectives and targets. In this work a general view of the Environmental Management System is presented and an example of one of the environmental programs to be implemented is detailed. (author)

  9. Selection of mining method for No.3 uranium ore body in the independent mining area at a uranium mine

    Ding Fulong; Ding Dexin; Ye Yongjun

    2010-01-01

    Mining operation in the existed mining area at a uranium mine is near completion and it is necessary to mine the No.3 uranium ore body in another mining area at the mine. This paper, based on the geological conditions, used analogical method for analyzing the feasible methods and the low cost and high efficiency mining method was suggested for the No.3 ore body in the independent mining area at the uranium mine. (authors)

  10. Evaluation and design of the uranium project “Tigre I – La Terraza”, Sierra Pintada, Mendoza, Argentina

    Mansilla, M.; Dieguez, S.

    2014-01-01

    The Sierra Pintada uranium district in Mendoza Province, Argentina, was discovered by airborne survey. This deposit is associated with a volcanic caldera and occurs in the Lower Permian volcaniclastic sediments of the Cochico Group, in which aeolian and fluvial sandstones, inter-bedded with ignimbrites, were reworked by pyroclastic flows. The origin of the mineralization is interpreted as a product of the leaching of the inter-bedded rhyolitic tuff. The mineralization is lenticular and nearly concordant with the bedding. The deposit has been affected by a complex fault system, which is responsible for mineralization and disposition via spatial displacement. The primary uranium minerals are uraninite, brannerite and coffinite. Uranophane and low liebigite uranium are the products of the oxidative alteration of primary minerals. This study involves the technical and economical evaluation of the open pit uranium mining project Tigre I – La Terraza in Mendoza, Argentina, at prefeasibility level. Its development includes geological modeling through economic evaluation, and the incorporation of different mining-specific software.

  11. Water and soil loss from landslide deposits as a function of gravel content in the Wenchuan earthquake area, China, revealed by artificial rainfall simulations.

    Gan, Fengling; He, Binghui; Wang, Tao

    2018-01-01

    A large number of landslides were triggered by the Mw7.9 Wenchuan earthquake which occurred on 12th May 2008. Landslides impacted extensive areas along the Mingjiang River and its tributaries. In the landslide deposits, soil and gravel fragments generally co-exist and their proportions may influence the hydrological and erosion processes on the steep slopes of the deposit surface. Understanding the effects of the mixtures of soil and gravels in landslide deposits on erosion processes is relevant for ecological reconstruction and water and soil conservation in Wenchuan earthquake area. Based on field surveys, indoor artificial rainfall simulation experiments with three rainfall intensities (1.0, 1.5 and 2.0 mm·min-1) and three proportions of gravel (50%, 66.7% and 80%) were conducted to measure how the proportion of gravel affected soil erosion and sediment yield in landslide sediments and deposits. Where the proportion of gravel was 80%, no surface runoff was produced during the 90 minute experiment under all rainfall intensities. For the 66.7% proportion, no runoff was generated at the lowest rainfall intensity (1.0 mm·min-1). As a result of these interactions, the average sediment yield ranked as 50> 66.6> 80% with different proportions of gravel. In addition, there was a positive correlation between runoff generation and sediment yield, and the sediment yield lagging the runoff generation. Together, the results demonstrate an important role of gravel in moderating the mobilization of landslide sediment produced by large earthquakes, and could lay the foundation for erosion models which provide scientific guidance for the control of landslide sediment in the Wenchuan earthquake zone, China.

  12. Fish and wildlife evaluation of wetlands created by mining activities

    Kepler, S.R.; Sabolcik, T.M.

    1994-01-01

    Four lacustrine wetland systems in Pennsylvania created by mining activities, either by sand and gravel or bituminous coal removal, were samples to determine the functional values of the fish and wildlife habitat. Most of the sampled sites were remnants of pre-act (1977) mining where minimal, if any, reclamation techniques were used. Natural succession within these impoundments have created ecosystems different in quality based on the availability of suitable habitat. Sampling techniques used to evaluate the wetland systems included initial water quality analyses, and aquatic habitat mapping using visual observations, LCD recorder, and computerized chart recorder. Fish populations were sampled using a boat mounted D.C. electrofishing unit with game fish being collected, weighted and measured and population estimates calculated as catch per unit effort (CPUE). Wildlife utilization of each site was conducted during the spring nesting season. Each site was surveyed for species utilization, nest searches determined whether nesting occurred and nesting success was noted. Wildlife utilization was determined by observation, tracks, calls, scat, etc. Whenever possible sites were monitored during the fall migration period to determine whether the sites were being utilized by migratory waterfowl. Wetland vegetative studies were also conducted at each site. Wetland species were identified and concentrations and dispersion of each wetland species were noted. Each sampled wetland data set is presented separately because of the variabilities between sampled sites based on the geology, reclamation status, and habitat

  13. Security Measures in Data Mining

    Anish Gupta; Vimal Bibhu; Rashid Hussain

    2012-01-01

    Data mining is a technique to dig the data from the large databases for analysis and executive decision making. Security aspect is one of the measure requirement for data mining applications. In this paper we present security requirement measures for the data mining. We summarize the requirements of security for data mining in tabular format. The summarization is performed by the requirements with different aspects of security measure of data mining. The performances and outcomes are determin...

  14. Floods, Droughts and Farming on the Plains of Argentina and ...

    2015-04-01

    Floods, Droughts and Farming on the Plains of Argentina and Paraguay, Pampas and Chaco Regions ... End Date. April 1, 2015 ... Argentina, South America, Paraguay, North and Central America ... IDRC is now accepting applications for this year's IDRC Doctoral Research Awards (IDRA). ... Careers · Contact Us · Site map.

  15. Argentina v globalizačních procesech

    Chervets, Tamara

    2009-01-01

    The process of globalization is a very important issue these days. This work will describe the process of globalization in Argentina, especially its economic aspect (foreign direct investments, export and import of goods and services, migration of labor force). I will also mention the history of its development and Argentina's membership in most important international and regional organizations.

  16. Computing and Education in Argentina, Uruguay and Paraguay.

    Sadowsky, Manuel

    Although the report is specifically about Argentina, Uruguay and Paraguay, the considerations presented are valid for all of Latin America. In September, 1969, Argentina had approximately 200 electronic computers. The annual growth is estimated at 15-20% and the implementation of teleprocessing and time-sharing systems have made evident the…

  17. All projects related to Argentina | Page 7 | IDRC - International ...

    Region: Americas, Argentina, South America. Program: Climate Change. Total Funding: CA$ 995,000.00. Youth Smoking in Stressed Environments : Determinants and Resiliency (Argentina, Colombia, Palestine). Project. Numerous studies have shown that the earlier an individual starts smoking, the harder it is to give it up.

  18. Unemployment Assistance and Transition to Employment in Argentina

    A. Iturriza (Ana); A.S. Bedi (Arjun Singh); R.A. Sparrow (Robert)

    2007-01-01

    textabstractIn 2001-02, Argentina experienced a wrenching economic crisis. Plan Jefes, implemented in May 2002, was Argentina's institutional response to the increases in unemployment and poverty triggered by the crisis. The program provided a social safety net and appears to have successfully

  19. Argentina: Social Sectors in Crisis. A World Bank Country Study.

    World Bank, Washington, DC.

    Based on the findings of a two month visit to Argentina by a World Bank Mission in November/December of 1988, this report summarizes current economic, education, and social policies in Argentina. The four major areas targeted are the social sectors, education, health care, and housing. The analysis identifies critical problems in the organization…

  20. Prospect for Development of Open Access in Argentina

    Miguel, Sandra; Bongiovani, Paola C.; Gomez, Nancy D.; Bueno-de-la-Fuente, Gema

    2013-01-01

    This perspective article presents an overview of the Open Access movement in Argentina, from a global and regional (Latin American) context. The article describes the evolution and current state of initiatives by examining two principal approaches to Open Access in Argentina: "golden" and "green roads". The article will then…

  1. Diccionario del español de Argentina

    Haensch, Günther

    2000-01-01

    Diccionario del español de Argentina : español de Argentina - español de España / Günther Haensch ; Reinhold Werner. Madrid : Gredos, 2000. - LI, 729 S. - (Diccionarios contrastivos del español de América)

  2. Pro-Market Educational Governance: Is Argentina a Black Swan?

    Beech, Jason; Barrenechea, Ignacio

    2011-01-01

    In this article we explore ways in which pro-market discourses have been interpreted in policy initiatives in Argentina since the 1970s. Our argument is that even though pro-market discourses have guided reforms in many aspects of public policies in Argentina, the arena of education has overall been resistant to taking them up. The first part of…

  3. 1 Estudio Sectorial Sector lácteo de Argentina

    Resumen: La producción de leche y productos lácteos conforma en Argentina un importante complejo productivo, de larga trayectoria histórica y gran impacto económico y social. En Argentina, esta industria conforma un oligopolio diferenciado en el que coexisten unas pocas grandes empresas nacionales y ...

  4. 78 FR 46610 - Lemon Juice From Argentina and Mexico

    2013-08-01

    ... Argentina and Mexico Determination On the basis of the record \\1\\ developed in the subject five-year reviews... determines that termination of the suspended antidumping duty investigation on lemon juice from Mexico would...), entitled Lemon Juice from Argentina and Mexico: Investigation Nos. 731-TA-1105-1106 (Review). By order of...

  5. 78 FR 47006 - Lemon Juice From Argentina and Mexico

    2013-08-02

    ... Argentina and Mexico Determination On the basis of the record \\1\\ developed in the subject five-year reviews... determines that termination of the suspended antidumping duty investigation on lemon juice from Mexico would...), entitled Lemon Juice from Argentina and Mexico: Investigation Nos. 731-TA-1105-1106 (Review). By order of...

  6. CALYPTRANTHES TRICONA (MYRTACEAE, NUEVA CITA PARA LA FLORA ARGENTINA

    Sara G. Tressens

    1996-01-01

    Full Text Available Calyptranthes tricona D. Legrand (Myrtaceae es reportada por primera vez para la Argentina.  Se incluyen una descripción y una ilustración. Se presenta un clave para la identificación de las especies argentinas de Calyptranthes se da. Se discuten algunas observaciones sobre la nomenclatura C.concinna DC.

  7. Effects of near-bed turbulence and micro-topography on macroinvertebrate movements across contrasting gravel-bed surfaces (Invited)

    Buffin-Belanger, T. K.; Rice, S. P.; Reid, I.; Lancaster, J.

    2009-12-01

    Fluvial habitats can be described from a series of physical variables but to adequately address the habitat quality it becomes necessary to develop an understanding that combines the physical variables with the behaviour of the inhabitating organisms. The hypothesis of flow refugia provide a rational that can explain the persistence of macroinvertebrate communities in gravel-bed rivers when spates occur. The movement behaviour of macroinvertebrates is a key element to the flow refugia hypothesis, but little is known about how local near-bed turbulence and bed microtopography may affect macroinvertebrate movements. We reproduced natural gravel-bed substrates with contrasting gravel bed textures in a large flume where we were able to document the movement behaviour of the cased caddisfly Potamophylax latipennis for a specific discharge. The crawling paths and drift events of animals were analysed from video recordings. Characteristics of movements differ from one substrate to another. The crawling speed is higher for the small grain-size substrates but the mean travel distance remains approximately the same between substrates. For each substrate, the animals tended to follow consistent paths across the surface. The number of drift events and mean distance drifted is higher for the small grain-size substrate. ADV measurements close to the boundary allow detailed characterisation of near-bed hydraulic variables, including : skewness coefficients, TKE, UV correlation coefficients and integral time scales from autocorrelation analysis. For these variables, the vertical patterns of turbulence parameters are similar between the substrates but the amplitude of the average values and standard errors vary significantly. The spatial distribution of this variability is considered in relation to the crawling paths. It appears that the animals tend to crawl within areas of the substrate where low flow velocities and low turbulent kinetic energies are found, while sites that

  8. Using multiple bed load measurements: Toward the identification of bed dilation and contraction in gravel-bed rivers

    Marquis, G. A.; Roy, A. G.

    2012-02-01

    This study examines bed load transport processes in a small gravel-bed river (Béard Creek, Québec) using three complementary methods: bed elevation changes between successive floods, bed activity surveys using tags inserted into the bed, and bed load transport rates from bed load traps. The analysis of 20 flood events capable of mobilizing bed material led to the identification of divergent results among the methods. In particular, bed elevation changes were not consistent with the bed activity surveys. In many cases, bed elevation changes were significant (1 to 2 times the D50) even if the bed surface had not been activated during the flood, leading to the identification of processes of bed dilation and contraction that occurred over 10% to 40% of the bed surface. These dynamics of the river bed prevent accurate derivation of bed load transport rates from topographic changes, especially for low magnitude floods. This paper discusses the mechanisms that could explain the dilation and contraction of particles within the bed and their implications in fluvial dynamics. Bed contraction seems to be the result of the winnowing of the fine sediments under very low gravel transport. Bed dilation seems to occur on patches of the bed at the threshold of motion where various processes such as fine sediment infiltration lead to the maintenance of a larger sediment framework volume. Both processes are also influenced by flood history and the initial local bed state and in turn may have a significant impact on sediment transport and morphological changes in gravel-bed rivers.

  9. Mining activities at Neyveli

    Boopathy, P.V.; Rathinavel, R.

    1993-01-01

    Mining activities at lignite areas around Neyveli are described. Measures taken to safeguard the environment from despoliation of land, air pollution, noise pollution and effluents are described. (M.G.B.)

  10. Radiation in mines

    Rose, H.J.M.

    1982-01-01

    Radiation in mines is primarily associated with, but not restricted to, the exploitation of uranium bearing orebodies. The intent of this chapter is to convey some aspects of radiation control in the mining industry, the behaviour of the parent radon and its daughter products. An attempt was made to demonstrate that anything less than complete diligence by the ventilation personnel could result in rapid deterioration of the mine environment, and consequently high exposure rates. When the maximum annual exposure limit is 4,0 WLM (Working level month exposure) the ventilation official is not allowed the privilege of making an error. Ventilation planning in uranium mines is of prime importance and is very much a group involvement

  11. Pumps in mining

    1979-01-01

    This article looks at the pump industry as a whole, its historical links with the mining industry, their parallel develop ment, and at the individual manufacturers and pumps, services and auxillary products they have to offer.

  12. Data mining in agriculture

    Mucherino, Antonio; Pardalos, Panos M

    2009-01-01

    Data Mining in Agriculture represents a comprehensive effort to provide graduate students and researchers with an analytical text on data mining techniques applied to agriculture and environmental related fields. This book presents both theoretical and practical insights with a focus on presenting the context of each data mining technique rather intuitively with ample concrete examples represented graphically and with algorithms written in MATLAB®. Examples and exercises with solutions are provided at the end of each chapter to facilitate the comprehension of the material. For each data mining technique described in the book variants and improvements of the basic algorithm are also given. Also by P.J. Papajorgji and P.M. Pardalos: Advances in Modeling Agricultural Systems, 'Springer Optimization and its Applications' vol. 25, ©2009.

  13. Acid Mine Drainage Treatment

    Fripp, Jon

    2000-01-01

    .... Acid mine drainage (AMD) can have severe impacts to aquatic resources, can stunt terrestrial plant growth and harm wetlands, contaminate groundwater, raise water treatment costs, and damage concrete and metal structures...

  14. Automatic identification in mining

    Puckett, D; Patrick, C [Mine Computers and Electronics Inc., Morehead, KY (United States)

    1998-06-01

    The feasibility of monitoring the locations and vital statistics of equipment and personnel in surface and underground mining operations has increased with advancements in radio frequency identification (RFID) technology. This paper addresses the use of RFID technology, which is relatively new to the mining industry, to track surface equipment in mine pits, loading points and processing facilities. Specific applications are discussed, including both simplified and complex truck tracking systems and an automatic pit ticket system. This paper concludes with a discussion of the future possibilities of using RFID technology in mining including monitoring heart and respiration rates, body temperatures and exertion levels; monitoring repetitious movements for the study of work habits; and logging air quality via personnel sensors. 10 refs., 5 figs.

  15. Uranium mines of Tajikistan

    Razykov, Z.A; Gusakov, E.G.; Marushenko, A.A.; Botov, A.Yu.; Yunusov, M.M.

    2002-12-01

    The book describes location laws, the main properties of geological structure and industrial perspectives for known uranium mines of the Republic of Tajikistan. Used methods of industrial processing of uranium mines are described. The results of investigations of technological properties of main types of uranium ores and methods of industrial processing of some of them are shown. Main properties of uranium are shortly described as well as problems, connected with it, which arise during exploitation, mining and processing of uranium ores. The main methods of solution of these problems are shown. The book has interest for specialists of mining, geological, chemical, and technological fields as well as for students of appropriate universities. This book will be interested for usual reader, too, if they are interested in mineral resources of their country [ru

  16. Acid mine drainage

    Bigham, Jerry M.; Cravotta, Charles A.

    2016-01-01

    Acid mine drainage (AMD) consists of metal-laden solutions produced by the oxidative dissolution of iron sulfide minerals exposed to air, moisture, and acidophilic microbes during the mining of coal and metal deposits. The pH of AMD is usually in the range of 2–6, but mine-impacted waters at circumneutral pH (5–8) are also common. Mine drainage usually contains elevated concentrations of sulfate, iron, aluminum, and other potentially toxic metals leached from rock that hydrolyze and coprecipitate to form rust-colored encrustations or sediments. When AMD is discharged into surface waters or groundwaters, degradation of water quality, injury to aquatic life, and corrosion or encrustation of engineered structures can occur for substantial distances. Prevention and remediation strategies should consider the biogeochemical complexity of the system, the longevity of AMD pollution, the predictive power of geochemical modeling, and the full range of available field technologies for problem mitigation.

  17. Scalable Frequent Subgraph Mining

    Abdelhamid, Ehab

    2017-01-01

    Given an input graph, the Frequent Subgraph Mining (FSM) task finds all subgraphs with frequencies exceeding a given threshold. FSM is crucial for graph analysis, and it is an essential building block in a variety

  18. Ensemble Data Mining Methods

    National Aeronautics and Space Administration — Ensemble Data Mining Methods, also known as Committee Methods or Model Combiners, are machine learning methods that leverage the power of multiple models to achieve...

  19. Coal mine subsidence

    Rahall, N.J.

    1991-05-01

    This paper examines the efficacy of the Department of the Interior's Office of Surface Mining Reclamation and Enforcement's (OSMRE) efforts to implement the federally assisted coal mine subsidence insurance program. Coal mine subsidence, a gradual settling of the earth's surface above an underground mine, can damage nearby land and property. To help protect property owners from subsidence-related damage, the Congress passed legislation in 1984 authorizing OSMRE to make grants of up to $3 million to each state to help the states establish self-sustaining, state-administered insurance programs. Of the 21 eligible states, six Colorado, Indiana, Kentucky, Ohio, West Virginia, and Wyoming applied for grants. This paper reviews the efforts of these six states to develop self-sustaining insurance programs and assessed OSMRE's oversight of those efforts

  20. Application of surface-geophysical methods to investigations of sand and gravel aquifers in the glaciated Northeastern United States

    Haeni, F.P.

    1995-01-01

    Combined use of seismic-refraction, direct-current resistivity, very-low-frequency terrain-resistivity, and inductive terrain-conductivity methods were demonstrated at sites in Connecticut, New York, and Maine. Although no single method can define both the hydrogeologic boundaries and general grain-size characteristics of sand and gravel aquifers, a combination of these methods can. Comparisons of measured electrical properties of aquifers with logs of test holes and wells indicate that, for a given conductivity of ground water, the bulk electrical resistivity of aquifers in the glaciated Northeast increases with grain size.