WorldWideScience

Sample records for surface mining simulator

  1. Visual simulation: a planning and design tool for surface mining

    International Nuclear Information System (INIS)

    Scott, R.D.

    1984-01-01

    Due to the controversial nature of the high level nuclear waste repository project proposed near Canyonlands National Park, public reaction has been considerable, particularly on visual impacts. Canyonlands is a primitive park; its appeal is solitude and pristine landscape. The Bureau of Land Management (BLM), the lead review agency, strongly recommended that the DOE employ visual simulation for displaying effects of visual change for the exploratory shaft, railroad access routes, and repository. As a result this study was conducted to address the concern for scenic values and the potential visual change within and surrounding the lands of Canyonlands National Park

  2. Simulated effects of surface coal mining and agriculture on dissolved solids in the Redwater River, east-central Montana

    Science.gov (United States)

    Ferreira, R.F.; Lambing, J.H.

    1985-01-01

    Dissolved solids concentrations in five reaches of the Redwater River in east-central Montana were simulated to evaluate the effects of surface coal mining and agriculture. A mass-balance model of streamflow and dissolved solids load developed for the Tongue River in southeastern Montana was modified and applied to the Redwater River. Mined acreages, dissolved solids concentrations in mined spoils, and irrigated acreage can be varied in the model to study relative changes in the dissolved solids concentration in consecutive reaches of the river. Because of extreme variability and a limited amount of data, the model was not consecutively validated. Simulated mean and median monthly mean streamflows and consistently larger than those calculated from streamflow records. Simulated mean and median monthly mean dissolved solids loads also are consistently larger than regression-derived values. These discrepancies probably result from extremely variable streamflow, overestimates of streamflow from ungaged tributaries, and weak correlations between streamflow and dissolved solids concentrations. The largest increases in simulated dissolved solids concentrations from mining and agriculture occur from September through January because of smaller streamflows and dissolved solids loads. Different combinations of agriculture and mining under mean flow conditions resulted in cumulative percentage increases of dissolved solids concentrations of less than 5% for mining and less than 2% for agriculture. (USGS)

  3. Effects of wearing gumboots and leather lace-up boots on lower limb muscle activity when walking on simulated underground coal mine surfaces.

    Science.gov (United States)

    Dobson, Jessica A; Riddiford-Harland, Diane L; Steele, Julie R

    2015-07-01

    This study aimed to investigate the effects of wearing two standard underground coal mining work boots (a gumboot and a leather lace-up boot) on lower limb muscle activity when participants walked across simulated underground coal mining surfaces. Quadriceps (rectus femoris, vastus medialis, vastus lateralis) and hamstring (biceps femoris, semitendinosus) muscle activity were recorded as twenty male participants walked at a self-selected pace around a circuit while wearing each boot type. The circuit consisted of level, inclined and declined surfaces composed of rocky gravel and hard dirt. Walking in a leather lace-up boot, compared to a gumboot, resulted in increased vastus lateralis and increased biceps femoris muscle activity when walking on sloped surfaces. Increased muscle activity appears to be acting as a slip and/or trip prevention strategy in response to challenging surfaces and changing boot features. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  4. Surface Mines, Other - Longwall Mining Panels

    Data.gov (United States)

    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...

  5. Potential utility of the thematic mapper for surface mine monitoring

    International Nuclear Information System (INIS)

    Irons, J.R.; Lachowski, H.M.

    1981-01-01

    One of many potential applications of the thematic mapper (TM) is surface mine monitoring. To assess this potential, data acquired by an aircraft multispectral scanner over Pennsylvania surface mines were preprocessed to simulate the anticipated spectral, spatial, and radiometric characteristics of TM data. False color imagery and thematic maps were derived from the simulated data and compared to imagery and maps derived from LANDSAT multispectral scanner subsystems data. On the basis of this comparison, TM data should definitely increase the detail and accuracy of remotely acquired surface mine information and may enable the remote determination of compliance with reclamation regulations

  6. Applying WEPP technologies to western alkaline surface coal mines

    Science.gov (United States)

    J. Q. Wu; S. Dun; H. Rhee; X. Liu; W. J. Elliot; T. Golnar; J. R. Frankenberger; D. C. Flanagan; P. W. Conrad; R. L. McNearny

    2011-01-01

    One aspect of planning surface mining operations, regulated by the National Pollutant Discharge Elimination System (NPDES), is estimating potential environmental impacts during mining operations and the reclamation period that follows. Practical computer simulation tools are effective for evaluating site-specific sediment control and reclamation plans for the NPDES....

  7. Applications of Geomatics in Surface Mining

    Science.gov (United States)

    Blachowski, Jan; Górniak-Zimroz, Justyna; Milczarek, Wojciech; Pactwa, Katarzyna

    2017-12-01

    In terms of method of extracting mineral from deposit, mining can be classified into: surface, underground, and borehole mining. Surface mining is a form of mining, in which the soil and the rock covering the mineral deposits are removed. Types of surface mining include mainly strip and open-cast methods, as well as quarrying. Tasks associated with surface mining of minerals include: resource estimation and deposit documentation, mine planning and deposit access, mine plant development, extraction of minerals from deposits, mineral and waste processing, reclamation and reclamation of former mining grounds. At each stage of mining, geodata describing changes occurring in space during the entire life cycle of surface mining project should be taken into consideration, i.e. collected, analysed, processed, examined, distributed. These data result from direct (e.g. geodetic) and indirect (i.e. remote or relative) measurements and observations including airborne and satellite methods, geotechnical, geological and hydrogeological data, and data from other types of sensors, e.g. located on mining equipment and infrastructure, mine plans and maps. Management of such vast sources and sets of geodata, as well as information resulting from processing, integrated analysis and examining such data can be facilitated with geomatic solutions. Geomatics is a discipline of gathering, processing, interpreting, storing and delivering spatially referenced information. Thus, geomatics integrates methods and technologies used for collecting, management, processing, visualizing and distributing spatial data. In other words, its meaning covers practically every method and tool from spatial data acquisition to distribution. In this work examples of application of geomatic solutions in surface mining on representative case studies in various stages of mine operation have been presented. These applications include: prospecting and documenting mineral deposits, assessment of land accessibility

  8. 12th International Symposium Continuous Surface Mining

    CERN Document Server

    2015-01-01

    This edited volume contains research results presented at the 12th International Symposium Continuous Surface Mining, ISCSM Aachen 2014. The target audience primarily comprises researchers in the lignite mining industry and practitioners in this field but the book may also be beneficial for graduate students.

  9. 30 CFR 780.27 - Reclamation plan: Surface mining near underground mining.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Reclamation plan: Surface mining near underground mining. 780.27 Section 780.27 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR SURFACE COAL MINING AND RECLAMATION OPERATIONS PERMITS AND COAL...

  10. Wide Strip Backfill Mining for Surface Subsidence Control and Its Application in Critical Mining Conditions of a Coal Mine

    Directory of Open Access Journals (Sweden)

    Wenhao Cao

    2018-03-01

    Full Text Available Critical mining under buildings, railways, and water bodies (BRW brings the contradiction between high recovery rate and minor environmental hazards. To lessen this contradiction, an innovative mining method referred to as “wide strip backfill mining” (WSBM was proposed in this study. A Winkler beam model is applied to the primary key strata (PKS, and the study revealed a surface subsidence control mechanism and designed the technical parameters of the method. The respective numerical simulations suggested the feasibility of the proposed method and the main influencing factors on surface subsidence can be ranked in descending order as wide filling strip width (WFSW, filling ratio, and pillar width. Meanwhile, a drop in the WFSW from 96 m to 72 m brought out the surface subsidence reduction by 44.5%. By using the super-high water content filling material, the proposed method was applied in the Taoyi coal mine under critical mining conditions. The resulting surface subsidence and deformations met the safety requirements for building protection level 1, and the recovery rate reached 75.9%. Moreover, the application of the method achieved significant technical and economic benefits. The research can provide a theoretical and experimental substantiation for critical mining under BRW.

  11. Surface mining and land reclamation in Germany

    Energy Technology Data Exchange (ETDEWEB)

    Nephew, E.A.

    1972-05-01

    Mining and land restoration methods as well as planning and regulatory procedures employed in West Germany to ameliorate environmental impacts from large-scale surface mining are described. The Rhineland coalfield in North Rhine Westphalia contains some 55 billion tons of brown-coal (or lignite), making the region one of Europe's most important energy centers. The lignite is extracted from huge, open-pit mines, resulting in large areas of disturbed land. The German reclamation approach is characterized by planning and carrying out the mining process as one continuum from early planning to final restoration of land and its succeeding use. Since the coalfield is located in a populated region with settlements dating back to Roman times, whole villages lying in the path of the mining operations sometimes have to be evacuated and relocated. Even before mining begins, detailed concepts must be worked out for the new landscape which will follow: the topography, the water drainage system, lakes and forests, and the intended land-use pattern are designed and specified in advance. Early, detailed planning makes it possible to coordinate mining and concurrent land reclamation activities. The comprehensive approach permits treating the overall problem as a whole rather than dealing with its separate aspects on a piecemeal basis.

  12. Range of drainage effect of surface mines

    Energy Technology Data Exchange (ETDEWEB)

    Sozanski, J.

    1978-03-01

    This paper discusses methods of calculating the range of effects of water drainage from surface coal mines and other surface mines. It is suggested that methods based on test pumping (water drainage) are time consuming, and the results can be distorted by atmospheric factors such as rain fall or dry period. So-called empirical formulae produce results which are often incorrect. The size of a cone shaped depression calculated on the basis of empirical formulae can be ten times smaller than the size of the real depression. It is suggested that using a formula based on the Dupuit formula is superior to other methods of depression calculation. According to the derived formulae the radius of the depresion cone is a function of parameters of the water bearing horizons, size of surface mine working and of water depression. The proposed formula also takes into account the influence of atmospheric factors (water influx caused by precipitation, etc.). (1 ref.) (In Polish)

  13. Carbon Sequestration on Surface Mine Lands

    Energy Technology Data Exchange (ETDEWEB)

    Donald Graves; Christopher Barton; Richard Sweigard; Richard Warner; Carmen Agouridis

    2006-03-31

    Since the implementation of the federal Surface Mining Control and Reclamation Act of 1977 (SMCRA) in May of 1978, many opportunities have been lost for the reforestation of surface mines in the eastern United States. Research has shown that excessive compaction of spoil material in the backfilling and grading process is the biggest impediment to the establishment of productive forests as a post-mining land use (Ashby, 1998, Burger et al., 1994, Graves et al., 2000). Stability of mine sites was a prominent concern among regulators and mine operators in the years immediately following the implementation of SMCRA. These concerns resulted in the highly compacted, flatly graded, and consequently unproductive spoils of the early post-SMCRA era. However, there is nothing in the regulations that requires mine sites to be overly compacted as long as stability is achieved. It has been cultural barriers and not regulatory barriers that have contributed to the failure of reforestation efforts under the federal law over the past 27 years. Efforts to change the perception that the federal law and regulations impede effective reforestation techniques and interfere with bond release must be implemented. Demonstration of techniques that lead to the successful reforestation of surface mines is one such method that can be used to change perceptions and protect the forest ecosystems that were indigenous to these areas prior to mining. The University of Kentucky initiated a large-scale reforestation effort to address regulatory and cultural impediments to forest reclamation in 2003. During the three years of this project 383,000 trees were planted on over 556 acres in different physiographic areas of Kentucky (Table 1, Figure 1). Species used for the project were similar to those that existed on the sites before mining was initiated (Table 2). A monitoring program was undertaken to evaluate growth and survival of the planted species as a function of spoil characteristics and

  14. Using simulated wetlands to assess acid mine drainage treatment efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Karathanasis, A.D. (Kentucky University, Lexington, KY (USA). Dept. of Agronomy)

    1992-01-01

    The elevated acidity and increased solubility of toxic metals such as Al, Fe, Mn, Cu, and Zn associated with acid mine drainage (AMD) is causing increasing concern about possible toxic effects to plants, aquatic life, animals, and even humans in the coal regions of the Appalachian states. During the last few years, a new technology for treatment of acid mine discharges has emerged. The technology involves the construction of artificial wetlands with dominant vegetation [ital Typha] (cattails), [ital Sphagnum] (moss), certain algae, and other plant species which have the potential to treat small flows of acid mine water moving through them. Greenhouse experiments at the University of Kentucky involving AMD treatment by surface and subsurface flow simulated wetlands with [ital Typha] plants (cattails) grown in six different substrates showed significant differences among substrates in their ability to buffer mine drainage acidity and in metal removal efficiency. Of the six substrates tested, the pine-needle-and-hay mixtures were the most efficient over the peat, sphagnum moss and mine spoil mixtures in reducing acidity and Al, Cu and Zn concentrations in surface effluents. The majority of the substrates (except the mine spoil surface soil) showed similar efficiencies for Fe removal, but all substrates were a source rather than a sink for Mn in surface and subsurface flows. The results of this study suggest that short-term screenings of various substrate materials under greenhouse conditions such as those used in this investigation may provide useful information on the selection of the most efficient substrate for the metal(s) of interest and thus, help improve the performance of the wetland under construction. 2 figs.

  15. Survey of nine surface mines in North America. [Nine different mines in USA and Canada

    Energy Technology Data Exchange (ETDEWEB)

    Hayes, L.G.; Brackett, R.D.; Floyd, F.D.

    1981-01-01

    This report presents the information gathered by three mining engineers in a 1980 survey of nine surface mines in the United States and Canada. The mines visited included seven coal mines, one copper mine, and one tar sands mine selected as representative of present state of the art in open pit, strip, and terrace pit mining. The purpose of the survey was to investigate mining methods, equipment requirements, operating costs, reclamation procedures and costs, and other aspects of current surface mining practices in order to acquire basic data for a study comparing conventional and terrace pit mining methods, particularly in deeper overburdens. The survey was conducted as part of a project under DOE Contract No. DE-AC01-79ET10023 titled The Development of Optimal Terrace Pit Coal Mining Systems.

  16. Overcoming soil compaction in surface mine reclamation

    International Nuclear Information System (INIS)

    Sweigard, R.J.

    1991-01-01

    Rubber-tyred soil reconstruction equipment causes compaction of soil and means surface mine operators cannot satisfy crop yield standards defined by the Surface Mining Control and Reclamation Act. Soil compaction can be overcome by either modifying the reconstruction process or alleviating the problem, for example by deep tillage, once it occurs. The Dept. of Mining Engineering at the Institute of Mining and Minerals Research is conducting a laboratory investigation into a method of injecting low density porous organic material into a bin containing soil at the same time as the soil is ripped. This should prevent voids collapsing when subjected to forces from farm equipment and natural sources. Soil analyses are performed before and after the injection. Ripping and injection with ground pecan shells had a residual effect on nuclear bulk density compared to the initially compacted case and also showed an improvement in hydraulic conductivity. Work is in progress on modifying the system to handle other injection material and should lead on to field tests on a prototype involving both soil analysis and crop yield determination. 1 fig

  17. "easyMine" – realistic and systematic mine detection simulation tooltion

    Directory of Open Access Journals (Sweden)

    U. Böttger

    2004-01-01

    Full Text Available Mine detection is to date mainly performed with metal detectors, although new methods for UXO detection are explored worldwide. The main problem for the mine detection to date is, that there exist some ideas of which sensor combinations could yield a high score, but until now there is no systematic analysis of mine detection methods together with realistic environmental conditions to conclude on a physically and technically optimized sensor combination. This gap will be removed by a project “easyMine" (Realistic and systematic Mine Detection Simulation Tool which will result in a simulation tool for optimizing land mine detection in a realistic mine field. The project idea for this software tool is presented, that will simulate the closed chain of mine detection, including the mine in its natural environment, the sensor, the evaluation and application of the measurements by an user. The tool will be modularly designed. Each chain link will be an independent, exchangeable sub- module and will describe a stand alone part of the whole mine detection procedure. The advantage of the tool will be the evaluation of very different kinds of sensor combinations in relation of their real potential for mine detection. Three detection methods (metal detector, GPR and imaging IR-radiometry will be explained to be introduced into the easyMine software tool in a first step. An actual example for land mine detection problem will be presented and approaches for solutions with easyMine will be shown.

  18. NOVEL EXCAVATION TECHNOLOGIES FOR EFFICIENT AND ECONOMIC SURFACE MINING

    Energy Technology Data Exchange (ETDEWEB)

    Vladislav Kecojevic; Samuel Frimpong

    2005-05-01

    Ground excavation constitutes a significant component of production costs in any surface mining operation. The excavation process entails material digging and removal in which the equipment motion is constrained by the workspace geometry. A major excavation problem is the variability of material properties, resulting in varying mechanical energy input and stress loading of shovel dipper-and-tooth assembly across the working bench. This variability has a huge impact on the shovel dipper and tooth assembly in hard formations. With this in mind, the primary objectives of the project were to (i) provide the theoretical basis to develop the Intelligent Shovel Excavation (ISE) technology to solve the problems associated with excavation in material formations; (ii) advance knowledge and frontiers in shovel excavation through intelligent navigation; and (iii) submit proposal for the design, development and implementation of the ISE technology for shovel excavation at experimental surface mining sites. The mathematical methods were used to (i) develop shovel's kinematics and dynamics, and (ii) establish the relationship between shovel parameters and the resistive forces from the material formation during excavation process. The ADAMS simulation environment was used to develop the hydraulic and cable shovel virtual prototypes. Two numerical examples are included to test the theoretical hypotheses and the obtained results are discussed. The area of sensor technology was studied. Application of specific wrist-mounted sensors to characterize the material, bucket and frame assembly was determined. Data acquisition, display and control system for shovel loading technology was adopted. The concept of data acquisition and control system was designed and a shovel boom stresses were simulated. A multi-partner collaboration between research organizations, shovel manufacturer, hardware and sensor technology companies, and surface mining companies is proposed to test design

  19. Surface mine impoundments as wildlife and fish habitat

    Science.gov (United States)

    Mark A. Rumble

    1989-01-01

    Unreclaimed surface mine impoundments provide poor fish and wildlife habitat. Recommendations given here for reclaiming "prelaw" impoundments and creating new impoundments could provide valuable fish and wildlife habitat if incorporated into existing laws and mine plans.

  20. 30 CFR 912.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 912.764 Section 912.764 Mineral Resources OFFICE OF SURFACE MINING... WITHIN EACH STATE IDAHO § 912.764 Process for designating areas unsuitable for surface coal mining... coal mining and reclamation operations. ...

  1. Impact of surface coal mining on soil hydraulic properties

    Science.gov (United States)

    X. Liu; J. Q. Wu; P. W. Conrad; S. Dun; C. S. Todd; R. L. McNearny; William Elliot; H. Rhee; P. Clark

    2016-01-01

    Soil erosion is strongly related to soil hydraulic properties. Understanding how surface coal mining affects these properties is therefore important in developing effective management practices to control erosion during reclamation. To determine the impact of mining activities on soil hydraulic properties, soils from undisturbed areas, areas of roughly graded mine...

  2. Mining-induced surface damage and the study of countermeasures

    International Nuclear Information System (INIS)

    Cui Jixian

    1994-01-01

    Coal constitutes China's major energy resource. The majority of the coal is produced from underground mining operations. Surface subsidence may amount to 80% of the thickness of the seam mined, while the subsided volume is around 60% of the mined volume underground. An area of 20 hectares of land will be affected with each 1 million tons of coal mined, thereby causing severe surface damage. Following a description of the characteristics of surface damages due to underground mining disturbance, this paper elaborates on the damage prediction method, standards applied for evaluating the damages experienced by surface buildings, land reclamation methods in subsided area, measures for reinforcing and protecting buildings in mining-affected areas, and performance of antideformation buildings

  3. Surface deformation of the secondary former mining areas

    Directory of Open Access Journals (Sweden)

    Tadeusz Głowacki

    2013-09-01

    Full Text Available The paper discuss the problem of secondary deformation observed on the surface of the land in the area of the old, non-existent copper and coal mines. The authors discuss the formation of the deformation in the final period of the mine, and after his arrest, after the close of any work of protecting the surface area of influence of mining activities. Discusses the reduction of the surface of the example of two disused mines: mining copper “Konrad” in Iwiny and “Thorez” in Walbrzych, an old coal mine. In the first part of the paper discusses a brief history of the creation of old copper basin and the Lower Silesian coal basin. It then discusses the formation of deformation processes in mining areas. Conducting continuous surveying allows you to monitor changes in the formation of land, in the paper indicate the source of the vertical displacements after ending of operation, the closure of the mine and stopped all work safety. In the area of Lower Silesia there are many remnants of disused mines, surface geodetic measurements show a constant activity in post-mining areas and the need to control the formation of the surface.

  4. Surface Mining: Soil, Coal, and Society

    Science.gov (United States)

    Singer, S. Fred

    Soil is a resource that is for all practical purposes nonrenewable. Natural soils have been formed over periods of thousands of years, although with intensive management and with inputs of nutrients and conditioners this time could be reduced.Coal is another precious resource, of critical importance as an interim fuel for perhaps the next hundred years or so, until renewable energy resources based on nuclear fusion or solar energy can become economic and widespread. Surface mining is the most efficient method for obtaining coal at lowest cost. But it disturbs the soil and takes it out of agricultural production for many years or decades, and sometimes forever, unless the land is properly restored at considerable cost.

  5. Reforesting unused surface mined lands by replanting with native trees

    Science.gov (United States)

    Patrick N. Angel; James A. Burger; Carl E. Zipper; Scott Eggerud

    2012-01-01

    More than 600,000 ha (1.5 million ac) of mostly forested land in the Appalachian region were surface mined for coal under the Surface Mining Control and Reclamation Act. Today, these lands are largely unmanaged and covered with persistent herbaceous species, such as fescue (Festuca spp.) and sericea lespedeza (Lespedeza cuneata [Dum. Cours.] G. Don,) and a mix of...

  6. Numerical Simulation of Squeezing Failure in a Coal Mine Roadway due to Mining-Induced Stresses

    Science.gov (United States)

    Gao, Fuqiang; Stead, Doug; Kang, Hongpu

    2015-07-01

    Squeezing failure is a common failure mechanism experienced in underground coal mine roadways due mainly to mining-induced stresses, which are much higher than the strength of rock mass surrounding an entry. In this study, numerical simulation was carried out to investigate the mechanisms of roadway squeezing using a novel UDEC Trigon approach. A numerical roadway model was created based on a case study at the Zhangcun coal mine in China. Coal extraction using the longwall mining method was simulated in the model with calculation of the mining-induced stresses. The process of roadway squeezing under severe mining-induced stresses was realistically captured in the model. Deformation phenomena observed in field, including roof sag, wall convexity and failed rock bolts are realistically produced in the UDEC Trigon model.

  7. 30 CFR 947.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 947.762 Section 947.762 Mineral Resources OFFICE OF SURFACE MINING... mining operations. Part 762 of this chapter, Criteria for Designating Areas Unsuitable for Surface Coal Mining Operations, shall apply to surface coal mining and reclamation operations. ...

  8. 30 CFR 921.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 921.762 Section 921.762 Mineral Resources OFFICE OF SURFACE MINING... mining operations. Part 762 of this chapter, Criteria for Designating Areas Unsuitable for Surface Coal Mining Operations, shall apply to surface coal mine operations. ...

  9. 30 CFR 942.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 942.764 Section 942.764 Mineral Resources OFFICE OF SURFACE MINING... WITHIN EACH STATE TENNESSEE § 942.764 Process for designating areas unsuitable for surface coal mining... Mining Operations, shall apply to surface coal mining and reclamation operations. (b) The Secretary shall...

  10. 30 CFR 941.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 941.762 Section 941.762 Mineral Resources OFFICE OF SURFACE MINING... mining operations. Part 762 of this chapter, Criteria for Designating Areas Unsuitable for Surface Coal Mining Operations, shall apply to surface coal mine operations. ...

  11. 30 CFR 933.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 933.762 Section 933.762 Mineral Resources OFFICE OF SURFACE MINING... mining operations. Part 762 of this chapter, Criteria for Designation Areas Unsuitable for Surface Coal Mining Operations, shall apply to surface coal mining and reclamation operations. ...

  12. 30 CFR 939.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 939.762 Section 939.762 Mineral Resources OFFICE OF SURFACE MINING... mining operations. Part 762 of this chapter, Criteria for Designating Areas Unsuitable for Surface Coal Mining Operations, shall apply to surface coal mining and reclamation operations. ...

  13. 30 CFR 905.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 905.762 Section 905.762 Mineral Resources OFFICE OF SURFACE MINING... mining operations. Part 762 of this chapter, Criteria for Designating Areas Unsuitable for Surface Coal Mining Operations, shall apply to surface coal mining operations. ...

  14. Simulating the Various Subsystems of a Coal Mine

    Directory of Open Access Journals (Sweden)

    V. Okolnishnikov

    2016-06-01

    Full Text Available A set of simulation models of various subsystems of a coal mine was developed with the help of a new visual interactive simulation system of technological processes. This paper contains a brief description of this simulation system and its possibilities. The main possibilities provided by the simulation system are: the quick construction of models from library elements, 3D representation, and the communication of models with actual control systems. These simulation models were developed for the simulation of various subsystems of a coal mine: underground conveyor network subsystems, pumping subsystems and coal face subsystems. These simulation models were developed with the goal to be used as a quality and reliability assurance tool for new process control systems in coal mining.

  15. An intelligent hybrid system for surface coal mine safety analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lilic, N.; Obradovic, I.; Cvjetic, A. [University of Belgrade, Belgrade (Serbia)

    2010-06-15

    Analysis of safety in surface coal mines represents a very complex process. Published studies on mine safety analysis are usually based on research related to accidents statistics and hazard identification with risk assessment within the mining industry. Discussion in this paper is focused on the application of AI methods in the analysis of safety in mining environment. Complexity of the subject matter requires a high level of expert knowledge and great experience. The solution was found in the creation of a hybrid system PROTECTOR, whose knowledge base represents a formalization of the expert knowledge in the mine safety field. The main goal of the system is the estimation of mining environment as one of the significant components of general safety state in a mine. This global goal is subdivided into a hierarchical structure of subgoals where each subgoal can be viewed as the estimation of a set of parameters (gas, dust, climate, noise, vibration, illumination, geotechnical hazard) which determine the general mine safety state and category of hazard in mining environment. Both the hybrid nature of the system and the possibilities it offers are illustrated through a case study using field data related to an existing Serbian surface coal mine.

  16. Surface Mining and Reclamation Effects on Flood Response of Watersheds in the Central Appalachian Plateau Region

    Science.gov (United States)

    Ferrari, J. R.; Lookingbill, T. R.; McCormick, B.; Townsend, P. A.; Eshleman, K. N.

    2009-01-01

    Surface mining of coal and subsequent reclamation represent the dominant land use change in the central Appalachian Plateau (CAP) region of the United States. Hydrologic impacts of surface mining have been studied at the plot scale, but effects at broader scales have not been explored adequately. Broad-scale classification of reclaimed sites is difficult because standing vegetation makes them nearly indistinguishable from alternate land uses. We used a land cover data set that accurately maps surface mines for a 187-km2 watershed within the CAP. These land cover data, as well as plot-level data from within the watershed, are used with HSPF (Hydrologic Simulation Program-Fortran) to estimate changes in flood response as a function of increased mining. Results show that the rate at which flood magnitude increases due to increased mining is linear, with greater rates observed for less frequent return intervals. These findings indicate that mine reclamation leaves the landscape in a condition more similar to urban areas rather than does simple deforestation, and call into question the effectiveness of reclamation in terms of returning mined areas to the hydrological state that existed before mining.

  17. Environmental impact assessment for surface coal mine - a case study

    International Nuclear Information System (INIS)

    Sen, P.; Chakraborty, K.

    1994-01-01

    Surface coal mines being the largest contributor to the national coal production, the study of environmental impacts due to this becomes mandatory as it will help in proper planning and safe operations of the mine in an environmentally compatible manner. Within the scope of this paper, a model for preparation of comprehensive environmental impact assessment (EIA) by utilising a new evaluation methodology leading to determination of Environmental Quality Designation an index has been developed and this model has been validated by using data from a running surface coal mine in Wardha Valley Coalfield. Based on this exercise, the overall impact of the surface coal mine under consideration on environment indicates a medium level and accordingly the control measures have to be planned. Thus repair to the environment has to be made a concurrent activity with mining i.e. to say we have to design with nature not against it

  18. Loosewall stability in United Kingdom surface coal mines

    Energy Technology Data Exchange (ETDEWEB)

    Stead, D.; Singh, R. (University of Saskatchewan, Saskatoon (Canada). Department of Geological Sciences)

    1989-05-01

    In order to successfully exploit surface coal mine reserves, a database was compiled over the last 10 years containing information on loosewall slope failures such as mine locality information, failure date, failure height, failure slope angle, failure depth, failure length, failure volume, assumed failure mechanism, pavement dip, failure surface type, water data, curvature of slope in plan and section, and mining method. Both the Bishop's simplified and the biplanar wedge methods were used to conduct a detailed two-dimensional limit equilibrium back. 11 figs., 31 refs.,

  19. The Effect of Mining Activity on the Surface in the Safety Shaft Pillar Area of Mayrau Mine

    Czech Academy of Sciences Publication Activity Database

    Živor, Roman; Klos, Pavel; Pechoč, Jiří; Brož, Milan

    M-24(340) (2002), s. 227-235 ISSN 0138-015X. [Polish-Czech-Slovakian Symposium on Mining Geophysics /28./. Niedzica, 11.06.2001-13.06.2001] R&D Projects: GA AV ČR IBS3086005 Institutional research plan: CEZ:AV0Z3046908 Keywords : shaft pillar * mining * surface subsidence Subject RIV: DH - Mining, incl. Coal Mining

  20. 30 CFR 910.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 910.764 Section 910.764 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE GEORGIA § 910.764 Process for designating areas unsuitable for surface coal mining...

  1. 30 CFR 903.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 903.762 Section 903.762 Mineral Resources OFFICE OF SURFACE MINING... WITHIN EACH STATE ARIZONA § 903.762 Criteria for designating areas as unsuitable for surface coal mining operations. Part 762 of this chapter, Criteria for Designating Areas Unsuitable for Surface Coal Mining...

  2. 30 CFR 922.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 922.762 Section 922.762 Mineral Resources OFFICE OF SURFACE MINING... WITHIN EACH STATE MICHIGAN § 922.762 Criteria for designating areas as unsuitable for surface coal mining operations. Part 762 of this chapter, Criteria for Designating Areas Unsuitable for Surface Coal Mining...

  3. 30 CFR 937.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 937.764 Section 937.764 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE OREGON § 937.764 Process for designating areas unsuitable for surface coal mining...

  4. 30 CFR 762.13 - Land exempt from designation as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 762.13 Section 762.13 Mineral Resources OFFICE OF SURFACE MINING... AREAS AS UNSUITABLE FOR SURFACE COAL MINING OPERATIONS § 762.13 Land exempt from designation as unsuitable for surface coal mining operations. The requirements of this part do not apply to— (a) Lands on...

  5. 30 CFR 762.15 - Exploration on land designated as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 762.15 Section 762.15 Mineral Resources OFFICE OF SURFACE MINING... AREAS AS UNSUITABLE FOR SURFACE COAL MINING OPERATIONS § 762.15 Exploration on land designated as unsuitable for surface coal mining operations. Designation of any area as unsuitable for all or certain types...

  6. 30 CFR 937.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 937.762 Section 937.762 Mineral Resources OFFICE OF SURFACE MINING... WITHIN EACH STATE OREGON § 937.762 Criteria for designating areas as unsuitable for surface coal mining operations. Part 762 of this chapter, Criteria for Designating Areas Unsuitable for Surface Coal Mining...

  7. 30 CFR 922.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 922.764 Section 922.764 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE MICHIGAN § 922.764 Process for designating areas unsuitable for surface coal mining...

  8. 30 CFR 912.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 912.762 Section 912.762 Mineral Resources OFFICE OF SURFACE MINING... WITHIN EACH STATE IDAHO § 912.762 Criteria for designating areas as unsuitable for surface coal mining operations. Part 762 of this chapter, Criteria for Designating Areas Unsuitable for Surface Coal Mining...

  9. 30 CFR 910.762 - Criteria for designating areas as unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... for surface coal mining operations. 910.762 Section 910.762 Mineral Resources OFFICE OF SURFACE MINING... WITHIN EACH STATE GEORGIA § 910.762 Criteria for designating areas as unsuitable for surface coal mining operations. Part 762 of this chapter, Criteria for Designating Areas Unsuitable for Surface Coal Mining...

  10. 30 CFR 941.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 941.764 Section 941.764 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE SOUTH DAKOTA § 941.764 Process for designating areas unsuitable for surface coal mining...

  11. 30 CFR 939.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 939.764 Section 939.764 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS WITHIN EACH STATE RHODE ISLAND § 939.764 Process for designating areas unsuitable for surface coal mining...

  12. Simulations of Muon Flux in Slanic Salt Mine

    Directory of Open Access Journals (Sweden)

    Mehmet Bektasoglu

    2012-01-01

    Full Text Available Geant4 simulation package was used to simulate muon fluxes at different locations, the floor of UNIREA mine and two levels of CANTACUZINO mine, of Slanic Prahova site in Romania. This site is specially important since it is one of the seven sites in Europe that are under consideration of housing large detector components of Large Apparatus studying Grand Unification and Neutrino Astrophysics (LAGUNA project. Simulations were performed for vertical muons and for muons with a zenith angle θ≤60°. Primary muon flux and energies at ground level were obtained from previous measurements. Results of the simulations are in general agreement with previous simulations made using MUSIC simulation program and with the measurements made using a mobile detector.

  13. Economic Impacts of Surface Mining on Household Drinking Water Supplies

    Science.gov (United States)

    This report provides information on the economic and social impacts of contaminated surface and ground water supplies on residents and households near surface mining operations. The focus is on coal slurry contamination of water supplies in Mingo County, West Virginia, and descr...

  14. 30 CFR 905.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 905.764 Section 905.764 Mineral Resources OFFICE OF SURFACE MINING... WITHIN EACH STATE CALIFORNIA § 905.764 Process for designating areas unsuitable for surface coal mining... coal mining operations beginning one year after the effective date of this program. ...

  15. 30 CFR 921.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 921.764 Section 921.764 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PROGRAMS FOR THE CONDUCT OF SURFACE MINING OPERATIONS... Coal Mining Operations, pertaining to petitioning, initial processing, hearing requirements, decisions...

  16. 30 CFR 947.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 947.764 Section 947.764 Mineral Resources OFFICE OF SURFACE MINING... WITHIN EACH STATE WASHINGTON § 947.764 Process for designating areas unsuitable for surface coal mining... coal mining and reclamation operations. (b) The Secretary shall notify the Washington Department of...

  17. 30 CFR 933.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 933.764 Section 933.764 Mineral Resources OFFICE OF SURFACE MINING... Coal Mining Operations, pertaining to petitioning, initial processing, hearing requirements, decisions... surface coal mining and reclamation operations beginning one year after the effective date of this program. ...

  18. 30 CFR 903.764 - Process for designating areas unsuitable for surface coal mining operations.

    Science.gov (United States)

    2010-07-01

    ... surface coal mining operations. 903.764 Section 903.764 Mineral Resources OFFICE OF SURFACE MINING... WITHIN EACH STATE ARIZONA § 903.764 Process for designating areas unsuitable for surface coal mining... coal mining operations beginning June 24, 1996, one year after the effective date of this program. ...

  19. Landfill mining: Development of a cost simulation model.

    Science.gov (United States)

    Wolfsberger, Tanja; Pinkel, Michael; Polansek, Stephanie; Sarc, Renato; Hermann, Robert; Pomberger, Roland

    2016-04-01

    Landfill mining permits recovering secondary raw materials from landfills. Whether this purpose is economically feasible, however, is a matter of various aspects. One is the amount of recoverable secondary raw material (like metals) that can be exploited with a profit. Other influences are the costs for excavation, for processing the waste at the landfill site and for paying charges on the secondary disposal of waste. Depending on the objectives of a landfill mining project (like the recovery of a ferrous and/or a calorific fraction) these expenses and revenues are difficult to assess in advance. This situation complicates any previous assessment of the economic feasibility and is the reason why many landfills that might be suitable for landfill mining are continuingly operated as active landfills, generating aftercare costs and leaving potential hazards to later generations. This article presents a newly developed simulation model for landfill mining projects. It permits identifying the quantities and qualities of output flows that can be recovered by mining and by mobile on-site processing of the waste based on treatment equipment selected by the landfill operator. Thus, charges for disposal and expected revenues from secondary raw materials can be assessed. Furthermore, investment, personnel, operation, servicing and insurance costs are assessed and displayed, based on the selected mobile processing procedure and its throughput, among other things. For clarity, the simulation model is described in this article using the example of a real Austrian sanitary landfill. © The Author(s) 2016.

  20. Carbon Sequestration on Surface Mine Lands

    Energy Technology Data Exchange (ETDEWEB)

    Donald H. Graves; Christopher Barton; Bon Jun Koo; Richard Sweigard; Richard Warner

    2004-11-30

    The first quarter of 2004 was dedicated to tree planting activities in two locations in Kentucky. During the first year of this project there was not available mine land to plant in the Hazard area, so 107 acres were planted in the Martin County mine location. This year 120 acres were planted in the Hazard area to compensate for the prior year and an additional 57 acres were planted on Peabody properties in western Kentucky. Additional sets of special plots were established on each of these areas that contained 4800 seedlings each for carbon sequestration demonstrations. Plantings were also conducted to continue compaction and water quality studies on the newly established areas as well as continual measurements of the first year's plantings. Total plantings on this project now amount to 357 acres containing 245,960 seedlings. During the second quarter of this year monitoring systems were established for all the new research areas. Weather data pertinent to the research as well as hydrology and water quality monitoring continues to be conducted on all areas. Studies established to assess specific questions pertaining to carbon flux and the invasion of the vegetation by small mammals are being quantified. Experimental practices initiated with this research project will eventually allow for the planting on long steep slopes with loose grading systems and allow mountain top removal areas to be constructed with loose spoil with no grading of the final layers of rooting material when establishing trees for the final land use designation. Monitoring systems have been installed to measure treatment effects on both above and below ground carbon and nitrogen pools in the planting areas. Soil and tissue samples were collected from both years planting and analyses were conducted in the laboratory. Examination of decomposition and heterotropic respiration on carbon cycling in the reforestation plots continued during the reporting period. Entire planted trees were

  1. Multiphase simulation of mine waters and aqueous leaching processes

    Directory of Open Access Journals (Sweden)

    Pajarre Risto

    2016-01-01

    Full Text Available Managing of large amounts of water in mining and mineral processing sites remains a concern in both actively operated and closed mining areas. When the mining site with its metal or concentrate producing units is operational, the challenge is to find either ways for economical processing with maximum yields, while minimizing the environmental impact of the water usage and waste salt treatments. For safe closure of the site, the environmental control of possible drainage will be needed. For both challenges, the present-day multiphase process simulations tools can be used to provide improved accuracy and better economy in controlling the smooth and environmentally sound operation of the plant. One of the pioneering studies in using the multiphase thermodynamic software in simulation of hydrometallurgical processes was that of Koukkari et al. [1]. The study covered the use of Solgasmix equilibrium software for a number of practical acid digesters. The models were made for sulfuric acid treatments in titania pigment production and in NPK fertilizer manufacturing. During the past two decades the extensive data assessment has taken place particularly in geochemistry and a new versions of geochemical multiphase equilibrium software has been developed. On the other hand, there has been some progress in development of the process simulation software in all the aforementioned fields. Thus, the thermodynamic simulation has become a tool of great importance in development of hydrometallurgical processes. The presentation will cover three example cases of either true pilot or industrial systems including a South African acid mine water drainage treatment, hydrometallurgical extraction of rare earths from uranium leachate in Russia and a multistage process simulation of a Finnish heap leaching mine with its subsequent water treatment system.

  2. CARBON SEQUESTRATION ON SURFACE MINE LANDS

    Energy Technology Data Exchange (ETDEWEB)

    Donald H. Graves; Christopher Barton; Richard Sweigard; Richard Warner

    2004-11-30

    A monitoring program to measure treatment effects on above ground, and below ground carbon and nitrogen pools for the planting areas is being conducted. The collection of soil and tissue samples from both the 2003 and 2004 plantings is complete and are currently being processed in the laboratory. Detailed studies have been initiated to address specific questions pertaining to carbon cycling. Examinations of decomposition and heterotropic respiration on carbon cycling in the reforestation plots were continued during this reporting period. A whole-tree harvesting method was employed to evaluate carbon accumulation as a function of time on the mined site. The trees were extracted from the sites and separated into the following components: foliage, stems, branches, and roots.

  3. An FMM-FFT Accelerated SIE Simulator for Analyzing EM Wave Propagation in Mine Environments Loaded with Conductors

    KAUST Repository

    Yucel, Abdulkadir C.

    2018-02-05

    A fast and memory efficient 3D full wave simulator for analyzing electromagnetic (EM) wave propagation in electrically large and realistic mine tunnels/galleries loaded with conductors is proposed. The simulator relies on Muller and combined field surface integral equations (SIEs) to account for scattering from mine walls and conductors, respectively. During the iterative solution of the system of SIEs, the simulator uses a fast multipole method - fast Fourier transform (FMM-FFT) scheme to reduce CPU and memory requirements. The memory requirement is further reduced by compressing large data structures via singular value and Tucker decompositions. The efficiency, accuracy, and real-world applicability of the simulator are demonstrated through characterization of EM wave propagation in electrically large mine tunnels/galleries loaded with conducting cables and mine carts.

  4. Analysis of Occupational Accidents in Underground and Surface Mining in Spain Using Data-Mining Techniques.

    Science.gov (United States)

    Sanmiquel, Lluís; Bascompta, Marc; Rossell, Josep M; Anticoi, Hernán Francisco; Guash, Eduard

    2018-03-07

    An analysis of occupational accidents in the mining sector was conducted using the data from the Spanish Ministry of Employment and Social Safety between 2005 and 2015, and data-mining techniques were applied. Data was processed with the software Weka. Two scenarios were chosen from the accidents database: surface and underground mining. The most important variables involved in occupational accidents and their association rules were determined. These rules are composed of several predictor variables that cause accidents, defining its characteristics and context. This study exposes the 20 most important association rules in the sector-either surface or underground mining-based on the statistical confidence levels of each rule as obtained by Weka. The outcomes display the most typical immediate causes, along with the percentage of accidents with a basis in each association rule. The most important immediate cause is body movement with physical effort or overexertion, and the type of accident is physical effort or overexertion. On the other hand, the second most important immediate cause and type of accident are different between the two scenarios. Data-mining techniques were chosen as a useful tool to find out the root cause of the accidents.

  5. Effect of arsenic on nitrification of simulated mining water.

    Science.gov (United States)

    Papirio, S; Zou, G; Ylinen, A; Di Capua, F; Pirozzi, F; Puhakka, J A

    2014-07-01

    Mining and mineral processing of gold-bearing ores often release arsenic to the environment. Ammonium is released when N-based explosives or cyanide are used. Nitrification of simulated As-rich mining waters was investigated in batch bioassays using nitrifying cultures enriched in a fluidized-bed reactor (FBR). Nitrification was maintained at 100mg AsTOT/L. In batch assays, ammonium was totally oxidized by the FBR enrichment in 48 h. As(III) oxidation to As(V) occurred during the first 3h attenuating arsenic toxicity to nitrification. At 150 and 200mg AsTOT/L, nitrification was inhibited by 25%. Candidatus Nitrospira defluvii and other nitrifying species mainly colonized the FBR. In conclusion, the FBR enriched cultures of municipal activated sludge origins tolerated high As concentrations making nitrification a potent process for mining water treatment. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Infiltration of surface mined land reclaimed by deep tillage treatments

    International Nuclear Information System (INIS)

    Chong, S.K.; Cowsert, P.

    1994-01-01

    Surface mining of coal leads to the drastic disturbance of soils. Compaction of replaced subsoil and topsoil resulting from hauling, grading, and leveling procedures produces a poor rooting medium for crop growth. Soil compaction results in high bulk density, low macroporosity, poor water infiltration capacity, and reduced elongation of plant roots. In the United States, Public Law 95-87 mandates that the rooting medium of mined soils have specific textural characteristics and be graded and shaped to a topography similar to premining conditions. Also, crop productivity levels equivalent to those prior to mining must be achieved, especially for prime farmland. Alleviation of compaction has been the major focus of reclamation, and recently new techniques to augment the rooting zone with deep-ripping and loosening equipment have come to the forefront. Several surface mine operators in the Illinois coal basin are using deep tillage equipment that is capable of loosening soils to greater depths than is possible with conventional farm tillage equipment. Information on the beneficial effects of these loosening procedures on soil hydrological properties, such as infiltration, runoff potential, erosion, and water retention, is extremely important for future mined land management. However, such information is lacking. In view of the current yield demonstration regulation for prime farmland and other unmined soils, it is important that as much information as possible be obtained concerning the effect of deep tillage on soil hydrologic properties. The objectives of this study are: (1) to compare infiltration rates and related soil physical properties of mined soils reclaimed by various deep tillage treatments and (2) to study the temporal variability of infiltration and related physical properties of the reclaimed mined soil after deep tillage treatment

  7. Reforestation of surface mines on lands of VICC Land Company

    Science.gov (United States)

    Thomas F. Evans

    1980-01-01

    This Virginia coal company's surface mined lands show an adequate stocking of tree seedlings in terms of number per acre, but the distribution of seedlings has been affected by past reclamation practices. Natural reseeding has been an important contributor to the present seedling stock.

  8. Hearing-impairment among workers in a surface gold mining ...

    African Journals Online (AJOL)

    A study to determine the impact of hazardous noise on workers was conducted in a surface gold mining company in Ghana. The procedure adopted included noise survey, case history, otoscopy and conventional pure-tone audiometry. Five main areas were surveyed for hazardous noise namely, Pit, Processing, Ana ...

  9. Chapter 10: Establishing native trees on legacy surface mines

    Science.gov (United States)

    J.A. Burger; C.E. Zipper; P.N. Angel; N. Hall; J.G. Skousen; C.D. Barton; S. Eggerud

    2017-01-01

    More than 1 million acres have been surface mined for coal in the Appalachian region. Today, much of this land is unmanaged, unproductive, and covered with nonnative plants. Establishing productive forests on such lands will aid restoration of ecosystem services provided by forests—services such as watershed protection, water quality enhancement, carbon storage, and...

  10. Solution of underground mine gas emissions on surface of abandoned mining sites where steep deposited coal seams have been exploited

    Energy Technology Data Exchange (ETDEWEB)

    Takla, G.; Froml, K. [OKD, DPB, Paskov (Czech Republic)

    2005-07-01

    The solution of uncontrolled gas emissions from abandoned underground coal mine sites in Ostrava-Karvina coal-field to surface ground in connection with old mine shafts and drifts and with old mining workings in horizontal and inclined coal seams has many forms. It varies according to geological and mining conditions and the disposition of the site surface. Since four years the gas emission risk has appeared in the area of former exploited vertical coal seams within the historical centre of Orlova town, which is protected by State Monument Protection office. A project based on such special nature of mining-geological and urban conditions was elaborated and already implemented. (authors)

  11. Solution of underground mine gas emissions on surface of abandoned mining sites where steep deposited coal seams have been exploited

    International Nuclear Information System (INIS)

    Takla, G.; Froml, K.

    2005-01-01

    The solution of uncontrolled gas emissions from abandoned underground coal mine sites in Ostrava-Karvina coal-field to surface ground in connection with old mine shafts and drifts and with old mining workings in horizontal and inclined coal seams has many forms. It varies according to geological and mining conditions and the disposition of the site surface. Since four years the gas emission risk has appeared in the area of former exploited vertical coal seams within the historical centre of Orlova town, which is protected by State Monument Protection office. A project based on such special nature of mining-geological and urban conditions was elaborated and already implemented. (authors)

  12. The spatiotempora variations rules of Songzao coal mining subsidence based on numerical simulation

    Directory of Open Access Journals (Sweden)

    J. Lu

    2015-11-01

    Full Text Available With the increasing demand of coal, coal mining at Songzao makes the area of land subsidence growing larger. Land subsidence in coal mining area not only made large subsided farmland out of production and caused the enormous loss to local agricultural production, but also brought a number of serious problems to the local social economy and ecology Environment. To use Probability-integral Method based on numerical simulation of Songzao Mine, its subsidence simulation data from 1999 to 2009 was obtained. Hence, overlay analysis between Goaf data and the simulation data in 2009, and between field investigation and the simulation data in 2009 were carried out. After the coal mining underground was identified as the crucial cause of surface subsidence. Therefore, the accuracy and feasibility of the simulation data had been verified, and the spatial pattern and spatiotemporal variations conforming to the actual values have been obtained. The results show five main findings. The first indicated that the surface subsidence is mostly located at the top of the Goaf, where the overlap areas between Goaf data and subsidence simulation data have accounted for 93.05 % of Goaf and 65.19 % of subsidence simulation data respectively. The second finding indicated that by end of 2009, the mining subsidence extent had reached about 5087.50 hm2. This area accounts for about 40 % of total of the mining area. The third finding indicated that within 10 years from 1999 to 2009, the influence range of subsidence has expanded about 2340.54 hm2, and the coal mining subsidence rate in Songzao Mine has increased gradually with time. Moreover, average increasing speed of the extent area in the second five years was larger than the first five years (about 75.08 hm2 yr−1 more. The fourth finding indicated that maximum subsidence has increased from 2.0 m in 1999 to 2.5 m in 2004, and then 3.0m in 2009 with subsidence rate of about 0.1 m yr−1. At the same time, the area

  13. Surface movement above an underground coal longwall mine after closure

    Science.gov (United States)

    Vervoort, André

    2016-09-01

    The surface movement in an area of about 22 km2 above the underground coal mine of Houthalen was analyzed based on Interferometry with Synthetic Aperture Radar (InSAR) measurements. After its closure in 1992, a residual subsidence was observed over a period of several years, followed by an uplift of the surface above and around the past longwall panels, whereby the rate of movement was, in absolute terms, of the same order for the two types of movements. The processes behind these movements are different. The process of subsidence is caused by the caving of the roof above the mined-out area and is mainly a mechanical stress-deformation process, including time-dependent aspects. However, the process of uplift is most probably caused by the swelling of the clay minerals in the argillaceous rocks in the coal strata after the flooding of the underground workings. Hence, the areas in which there is the greatest risk of damage to the surface infrastructure are not the same for the hazards linked to subsidence and uplift. For example, the zone in which the maximum uplift occurs clearly is at a different location from that of the zone with the maximum residual subsidence. There is no clear sign that the amount of mining underneath affects the residual subsidence, and there is no indication that the process of uplift is linked directly to the mining characteristics. It is more likely that uplift as the result of flooding is initiated at, or close to, the vertical shafts.

  14. Simultaneous caving and surface restoration system for oil shale mining

    Energy Technology Data Exchange (ETDEWEB)

    Allsman, P.T.

    1968-10-01

    A modified caving method is introduced for mining oil shale and simultaneous restoration of the land surface by return of spent shale onto the subsided area. Other methods have been designed to mine the relatively thin richer beds occurring near outcrops in the Piceance Creek Basin of NW. Colorado. Since the discovery of the much thicker beds in the N.-central part of the basin, some attention has focused on in situ and open-pit methods of recovery. Although caving has been recognized as a possible means of mining shale, most people have been skeptical of its success. This stems from the unknown and salient factors of cavability and size of broken rock with caving. Wisdom would seem to dictate that serious evaluation of the caving method be made along with the other methods.

  15. Underground coal mine subsidence impacts on surface water

    International Nuclear Information System (INIS)

    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

  16. Analysis of Occupational Accidents in Underground and Surface Mining in Spain Using Data-Mining Techniques

    Directory of Open Access Journals (Sweden)

    Lluís Sanmiquel

    2018-03-01

    Full Text Available An analysis of occupational accidents in the mining sector was conducted using the data from the Spanish Ministry of Employment and Social Safety between 2005 and 2015, and data-mining techniques were applied. Data was processed with the software Weka. Two scenarios were chosen from the accidents database: surface and underground mining. The most important variables involved in occupational accidents and their association rules were determined. These rules are composed of several predictor variables that cause accidents, defining its characteristics and context. This study exposes the 20 most important association rules in the sector—either surface or underground mining—based on the statistical confidence levels of each rule as obtained by Weka. The outcomes display the most typical immediate causes, along with the percentage of accidents with a basis in each association rule. The most important immediate cause is body movement with physical effort or overexertion, and the type of accident is physical effort or overexertion. On the other hand, the second most important immediate cause and type of accident are different between the two scenarios. Data-mining techniques were chosen as a useful tool to find out the root cause of the accidents.

  17. Analysis of Occupational Accidents in Underground and Surface Mining in Spain Using Data-Mining Techniques

    Science.gov (United States)

    Sanmiquel, Lluís; Bascompta, Marc; Rossell, Josep M.; Anticoi, Hernán Francisco; Guash, Eduard

    2018-01-01

    An analysis of occupational accidents in the mining sector was conducted using the data from the Spanish Ministry of Employment and Social Safety between 2005 and 2015, and data-mining techniques were applied. Data was processed with the software Weka. Two scenarios were chosen from the accidents database: surface and underground mining. The most important variables involved in occupational accidents and their association rules were determined. These rules are composed of several predictor variables that cause accidents, defining its characteristics and context. This study exposes the 20 most important association rules in the sector—either surface or underground mining—based on the statistical confidence levels of each rule as obtained by Weka. The outcomes display the most typical immediate causes, along with the percentage of accidents with a basis in each association rule. The most important immediate cause is body movement with physical effort or overexertion, and the type of accident is physical effort or overexertion. On the other hand, the second most important immediate cause and type of accident are different between the two scenarios. Data-mining techniques were chosen as a useful tool to find out the root cause of the accidents. PMID:29518921

  18. Private and social costs of surface mine reforestation performance criteria.

    Science.gov (United States)

    Sullivan, Jay; Amacher, Gregory S

    2010-02-01

    We study the potentially unnecessary costs imposed by strict performance standards for forest restoration of surface coal mines in the Appalachian region under the Surface Mining Control and Reclamation Act of 1977 (SMCRA) that can vary widely across states. Both the unnecessary private costs to the mine operator and costs to society (social costs) are reported for two performance standards, a ground cover requirement, and a seedling survival target. These standards are examined using numerical analyses under a range of site productivity class and market conditions. We show that a strict (90%) ground cover standard may produce an unnecessary private cost of more than $700/ha and a social cost ranging from $428/ha to $710/ha, as compared with a 70% standard. A strict tree survival standard of 1235 trees/ha, as compared with the more typical 1087 trees/ha standard, may produce an unnecessary private cost of approximately $200/ha, and a social cost in the range of $120 to $208/ha. We conclude that strict performance standards may impose substantial unnecessary private costs and social costs, that strict performance standards may be discouraging the choice of forestry as a post-mining land use, and that opportunities exist for reform of reforestation performance standards. Our study provides a basis for evaluating tradeoffs between regulatory efficiency and optimal reforestation effort.

  19. Achieving revegetation standards on surface mined lands. [Montana

    Energy Technology Data Exchange (ETDEWEB)

    Sindelar, B. W.

    1980-01-01

    Standards for revegetation success on surface mined lands have been developed by federal and state regulatory authorities. Because reclamation science is young, its potential for meeting revegetation standards is untested. This paper reviews the Montana revegetation standards which require establishment of a diverse, effective, and permanent vegetational cover. In addition, productivity, cover, and diversity must be comparable to that of reference areas. Fifty-one percent of the cover must be of native species. A plant succession study at Colstrip, MT, has been directed toward documenting establishment, succession, and stability of vegetation on surface mined land. Data from the study were used to discuss success of reclamation seedings since 1969. Major problem areas identified include achieving: comparable life form composition, cover of perennial vegetation, species diversity, and seasonality of forage and browse. Achieving erosion control, comparable production, and native species dominance did not appear to be major problems. Achieving revegetation standards on mined lands in the future will require very specialized reclamation procedures and continued research. Naturally revegetated mined lands at Colstrip indicate good potential for reclamation success.

  20. Assessment of the impact of underground mining on ground surface

    International Nuclear Information System (INIS)

    Toomik, Arvi

    1999-01-01

    The mine able oil shale bed is located in horizontally lying Ordovician limestones at a depth of 10-60 meters from the ground surface. Limestones are covered with Quaternary sediments, mainly till and loam, sporadically seams of clay occur. The overburden rocks of oil shale bed are jointed limestones with weak contacts between layers. The upper part of limestones is weakened additionally due to weathering to depths of 10-20 metres. Ground movements caused by mining reach the ground surface easily due to the shallow location of workings. The size and nature of these movements depend on mining and roof control methods used. In this study the impact of geotechnical processes on the ground surface caused by four different mining methods is analysed. A new, artificial micro relief is formed on undermined areas, where the ground surface depressions are alternating with rising grounds. When the Quaternary cover contains loamy sediments, the surface (rain) water will accumulate in the depressions. The response of usable lands on undermined areas depends on the degree of changes in the relief and water regime. There exists a maximum degree (limit) of changes of ground movements in case of which the changes in land use are not yet considerable. The factor of land deterioration was developed for arable and forest lands taking into account the character and degree of negative impacts. When no one deterioration factor exceeds the limit, the value of arable land will be 1.0 (100%). When some factor exceeds the limit, then water logging in subsidence troughs will diminish the value to 0.7, slopes to 0.8 and the area of weathered basic rocks to 0.9. In case of a combined effect of all these factors the value of arable land will fall to 0.5. As the long-term character of ground movement after room and pillar mining is not yet established, the factor for quasi stable areas is taken preliminarily as 0.9. Using detailed plans of mined out areas and the proposed factors, it is possible

  1. Damage to underground coal mines caused by surface blasting

    International Nuclear Information System (INIS)

    Fourie, A.B.; Green, R.W.

    1993-01-01

    An investigation of the potential damage to underground coal workings as a result of surface blasting at an opencast coal mine is described. Seismometers were installed in a worked out area of an underground mine, in the eastern Transvaal region of South Africa, and the vibration caused by nearby surface blasting recorded. These measurements were used to derive peak particle velocities. These velocities were correlated with observed damage underground in order to establish the allowable combination of the two blasting parameters of charge mass per relay, and blast-to-gage point distance. An upper limit of 110mm/sec peak particle velocity was found to be sufficient to ensure that the damage to the particular workings under consideration was minimal. It was further found that a cube-root scaling law provided a better fit to the field data than the common square-root law. 11 refs., 6 figs., 5 tabs

  2. Possibilities of surface waters monitoring at mining areas using UAV

    Science.gov (United States)

    Lisiecka, Ewa; Motyka, Barbara; Motyka, Zbigniew; Pierzchała, Łukasz; Szade, Adam

    2018-04-01

    The selected, remote measurement methods are discussed, useful for determining surface water properties using mobile unmanned aerial platforms (UAV). The possibilities of using this type of solutions in the scope of measuring spatial, physicochemical and biological parameters of both natural and anthropogenic water reservoirs, including flood polders, water-filled pits, settling tanks and mining sinks were analyzed. Methods of remote identification of the process of overgrowing this type of ecosystems with water and coastal plant formations have also been proposed.

  3. 3D modeling of surface quarries and deposits of mined materials and the monitoring of slopes

    OpenAIRE

    Ivan Maňas

    2007-01-01

    The application of computer technology by simulating opencast mining and deposits of raw materials. The mathematic principles of three-dimensional probabilistic models of raw materials deposits and a familiarization with the user interface software GEOLOGICKY MODEL. The principles of the simulation of opencast mines, generation intersections with models of raw materials deposits, computation of mining materials with the quality scaling,and the design of advanced mining with the software BANSK...

  4. 30 CFR 933.761 - Areas designated unsuitable for surface coal mining by Act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE NORTH CAROLINA § 933.761 Areas designated unsuitable for surface coal mining by Act of Congress. Part 761 of this chapter, Areas Designated Unsuitable for Coal Mining by Act of Congress, with the exception of §§ 761.11(c) and 761.12(f)(1), shall apply to surface coal mining and reclamation...

  5. 30 CFR 942.800 - Bond and insurance requirements for surface coal mining and reclamation operations.

    Science.gov (United States)

    2010-07-01

    ... required for postmining water treatment must remain bonded. However, the trust fund or annuity may serve as... coal mining and reclamation operations. 942.800 Section 942.800 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PROGRAMS FOR THE CONDUCT OF SURFACE MINING...

  6. Three-dimensional hydrogeologic modelling to simulate groundwater inflow at an abandoned underground coal mine in Korea

    Science.gov (United States)

    Baek, Hwanjo; Kim, Donghui; Kim, Gyoungman; Kim, Daehoon; Kim, Eunsoo; Kim, Dukmin

    2017-04-01

    The safety and environmental concerns should be addressed for sustainable mining operations, and one of the key issues is the prediction of the groundwater flow into underground mine workings. Prediction of the groundwater inflow requires a detailed knowledge of the geologic conditions, including the presence of major faults and other geologic structures at the mine site. The hydrologic boundaries and depth of the phreatic surface of the mine area, as well as other properties of the rockmass, are also provided. Various numerical models have been applied to develop hydrogeologic models at mine sites, and the MINEDW by Itasca is one of those groundwater flow model codes developed to simulate the groundwater flow related to mining. Mine sealing is one of the usual methods to control mine water at abandoned mines. An experimental program has been undertaken to provide a practical procedure for sealing abandoned coal mines in Korea. Two abandoned coal mines were selected, and extensive geological and geophysical surveys were performed. Field hydraulic tests, such as pumping tests and packer tests, had also been conducted to measure the hydraulic conductivities of the rock mass. In this study, constructing three-dimensional hydrogeologic models of the study area are essential for design and installation of the stable adit-plug system. With the complete 3D model constructed, the rate of mine water rebound after the installation of the adit-plug system can be hypothesized. The maximum water pressure affecting the stability of the plug, and the long-term seepage problems, can also be estimated.

  7. Surface mining machines problems of maintenance and modernization

    CERN Document Server

    Rusiński, Eugeniusz; Moczko, Przemysław; Pietrusiak, Damian

    2017-01-01

    This unique volume imparts practical information on the operation, maintenance, and modernization of heavy performance machines such as lignite mine machines, bucket wheel excavators, and spreaders. Problems of large scale machines (mega machines) are highly specific and not well recognized in the common mechanical engineering environment. Prof. Rusiński and his co-authors identify solutions that increase the durability of these machines as well as discuss methods of failure analysis and technical condition assessment procedures. "Surface Mining Machines: Problems in Maintenance and Modernization" stands as a much-needed guidebook for engineers facing the particular challenges of heavy performance machines and offers a distinct and interesting demonstration of scale-up issues for researchers and scientists from across the fields of machine design and mechanical engineering.

  8. Effect of Traditional Gold Mining to Surface Water Quality in Murung Raya District, Central Kalimantan Province

    OpenAIRE

    Wilopo, W; Resili, R; Putra, D P E

    2013-01-01

    There are many locations for traditional gold mining in Indonesia. One of these is in Murung Raya District, Central Kalimantan Province. Mining activities involving the application of traditional gold processing technology have a high potential to pollute the environment, especially surface water. Therefore, this study aims to determine the impact of gold mining and processing on surface water quality around the mine site. Based on the results of field surveys and laboratory analysis, our dat...

  9. Changes in nutrient, dissolved oxygen and total suspended matter during simulated placer mining

    Digital Repository Service at National Institute of Oceanography (India)

    Sijinkumar, A.V.; Naik, T.; Nath, B.N.; Sharma, R.

    In order to study the impact of placer mining on shallow coastal waters, a simulated sand mining experiment was carried out in Kalbadevi, Ratnagiri, west coast of India, which is recognized as one of the future sand mining sites. Water column...

  10. Gamma-ray spectroscopy measurements and simulations for uranium mining

    Directory of Open Access Journals (Sweden)

    Marchais T.

    2018-01-01

    Full Text Available AREVA Mines and the Nuclear Measurement Laboratory of CEA Cadarache are collaborating to improve the sensitivity and precision of uranium concentration evaluation by means of gamma measurements. This paper reports gamma-ray spectra, recorded with a high-purity coaxial germanium detector, on standard cement blocks with increasing uranium content, and the corresponding MCNP simulations. The detailed MCNP model of the detector and experimental setup has been validated by calculation vs. experiment comparisons. An optimization of the detector MCNP model is presented in this paper, as well as a comparison of different nuclear data libraries to explain missing or exceeding peaks in the simulation. Energy shifts observed between the fluorescence X-rays produced by MCNP and atomic data are also investigated. The qualified numerical model will be used in further studies to develop new gamma spectroscopy approaches aiming at reducing acquisition times, especially for ore samples with low uranium content.

  11. Gamma-ray spectroscopy measurements and simulations for uranium mining

    Science.gov (United States)

    Marchais, T.; Pérot, B.; Carasco, C.; Allinei, P.-G.; Chaussonnet, P.; Ma, J.-L.; Toubon, H.

    2018-01-01

    AREVA Mines and the Nuclear Measurement Laboratory of CEA Cadarache are collaborating to improve the sensitivity and precision of uranium concentration evaluation by means of gamma measurements. This paper reports gamma-ray spectra, recorded with a high-purity coaxial germanium detector, on standard cement blocks with increasing uranium content, and the corresponding MCNP simulations. The detailed MCNP model of the detector and experimental setup has been validated by calculation vs. experiment comparisons. An optimization of the detector MCNP model is presented in this paper, as well as a comparison of different nuclear data libraries to explain missing or exceeding peaks in the simulation. Energy shifts observed between the fluorescence X-rays produced by MCNP and atomic data are also investigated. The qualified numerical model will be used in further studies to develop new gamma spectroscopy approaches aiming at reducing acquisition times, especially for ore samples with low uranium content.

  12. Application of Discrete Event Simulation in Mine Production Forecast

    African Journals Online (AJOL)

    Mine production forecast is pertinent to mining as it serves production goals for a production period. Perseus Mining Ghana Limited (PMGL), Ayanfuri, deterministically forecasts mine production which sometimes result in significant variation from the actual production. This paper developed an innovative stochastic discrete ...

  13. Northern bobwhite breeding season ecology on a reclaimed surface mine

    Science.gov (United States)

    Brooke, Jarred M.; Tanner, Evan P.; Peters, David C.; Tanner, Ashley M.; Harper, Craig A.; Keyser, Patrick D.; Clark, Joseph D.; Morgan, John J.

    2017-01-01

    Surface coal mining and subsequent reclamation of surface mines have converted large forest areas into early successional vegetative communities in the eastern United States. This reclamation can provide a novel opportunity to conserve northern bobwhite (Colinus virginianus). We evaluated the influence of habitat management activities on nest survival, nest-site selection, and brood resource selection on managed and unmanaged units of a reclaimed surface mine, Peabody Wildlife Management Area (Peabody), in west-central Kentucky, USA, from 2010 to 2013. We compared resource selection, using discrete-choice analysis, and nest survival, using the nest survival model in Program MARK, between managed and unmanaged units of Peabody at 2 spatial scales: the composition and configuration of vegetation types (i.e., macrohabitat) and vegetation characteristics at nest sites and brood locations (i.e., microhabitat). On managed sites, we also investigated resource selection relative to a number of different treatments (e.g., herbicide, disking, prescribed fire). We found no evidence that nest-site selection was influenced by macrohabitat variables, but bobwhite selected nest sites in areas with greater litter depth than was available at random sites. On managed units, bobwhite were more likely to nest where herbicide was applied to reduce sericea lespedeza (Lespedeza cuneata) compared with areas untreated with herbicide. Daily nest survival was not influenced by habitat characteristics or by habitat management but was influenced by nest age and the interaction of nest initiation date and nest age. Daily nest survival was greater for older nests occurring early in the breeding season (0.99, SE < 0.01) but was lower for older nests occurring later in the season (0.08, SE = 0.13). Brood resource selection was not influenced by macrohabitat or microhabitat variables we measured, but broods on managed units selected areas treated with herbicide to control sericea lespedeza

  14. Preliminary analysis of surface mining options for Naval Oil Shale Reserve 1

    Energy Technology Data Exchange (ETDEWEB)

    1981-07-20

    The study was undertaken to determine the economic viability of surface mining to exploit the reserves. It is based on resource information already developed for NOSR 1 and conceptual designs of mining systems compatible with this resource. Environmental considerations as they relate to surface mining have been addressed qualitatively. The conclusions on economic viability were based primarily on mining costs projected from other industries using surface mining. An analysis of surface mining for the NOSR 1 resource was performed based on its particular overburden thickness, oil shale thickness, oil shale grade, and topography. This evaluation considered reclamation of the surface as part of its design and cost estimate. The capital costs for mining 25 GPT and 30 GPT shale and the operating costs for mining 25 GPT, 30 GPT, and 35 GPT shale are presented. The relationship between operating cost and stripping ratio, and the break-even stripping ratio (BESR) for surface mining to be competitive with room-and-pillar mining, are shown. Identification of potential environmental impacts shows that environmental control procedures for surface mining are more difficult to implement than those for underground mining. The following three areas are of prime concern: maintenance of air quality standards by disruption, movement, and placement of large quantities of overburden; disruption or cutting of aquifers during the mining process which affect area water supplies; and potential mineral leaching from spent shales into the aquifers. Although it is an operational benefit to place spent shale in the open pit, leaching of the spent shales and contamination of the water is detrimental. It is therefore concluded that surface mining on NOSR 1 currently is neither economically desirable nor environmentally safe. Stringent mitigation measures would have to be implemented to overcome some of the potential environmental hazards.

  15. Response of transplanted aspen to irrigation and weeding on a Colorado reclaimed surface coal mine

    Science.gov (United States)

    Robert C. Musselman; Wayne D. Shepperd; Frederick W. Smith; Lance A. Asherin; Brian W. Gee

    2012-01-01

    Successful re-establishment of aspen (Populus tremuloides Michx.) on surface-mined lands in the western United States is problematic because the species generally regenerates vegetatively by sprouting from parent roots in the soil; however, topsoil is removed in the mining process. Previous attempts to plant aspen on reclaimed mine sites have failed because...

  16. Uranium-production forecasting: the simulation of a South African gold mine

    International Nuclear Information System (INIS)

    Boydell, D.W.

    1979-01-01

    A computer program is described that estimates the amount of uranium that will be produced from a mine as a co-product of gold subject to a changing economic environment. The program makes use of two models. The first simulates activities underground, whereas the second simulates the performance of processing plant on the surface. The combination of these models generates a description of the flow of ore from stopes and from development, through hoisting, sorting, and the metallurgical plant to the despatch of saleable product. The total production of uranium to the end of the life of the mine constitutes the uranium reserve. The effects on production forecasts and reserve estimates of future trends in cost and price factors are illustrated by results generated from the application of the program to a typical South African mine producing gold and uranium. The graphs presented show that South Africa's future uranium production from underground sources is critically dependent on the gold price in the years ahead. (author)

  17. Gas migration from closed coal mines to the surface. Risk assessment methodology and prevention means

    International Nuclear Information System (INIS)

    Pokryszka, Z.; Tauziede, Ch.; Lagny, C.; Guise, Y.; Gobillot, R.; Planchenault, J.M.; Lagarde, R.

    2005-01-01

    French law as regards renunciation to mining concessions calls for the mining operator to first undertake analyses of the risks represented by their underground mining works. The problem of gas migration to the surface is especially significant in the context of coal mines. This is because mine gas can migrate to the earth's surface, then present significant risks: explosion, suffocation or gas poisoning risks. As part of the scheduled closure of all coal mining operations in France, INERIS has drawn up, at the request of national mining operator Charbonnages de France, a general methodology for assessing the risk linked to gas in the context of closed coal mines. This article presents the principles of this methodology. An application example based on a true case study is then described. This is completed by a presentation of the preventive and monitoring resources recommended and usually applied in order to manage the risk linked to gaseous emissions. (authors)

  18. Mining data from hemodynamic simulations via Bayesian emulation

    Directory of Open Access Journals (Sweden)

    Nair Prasanth B

    2007-12-01

    Full Text Available Abstract Background: Arterial geometry variability is inevitable both within and across individuals. To ensure realistic prediction of cardiovascular flows, there is a need for efficient numerical methods that can systematically account for geometric uncertainty. Methods and results: A statistical framework based on Bayesian Gaussian process modeling was proposed for mining data generated from computer simulations. The proposed approach was applied to analyze the influence of geometric parameters on hemodynamics in the human carotid artery bifurcation. A parametric model in conjunction with a design of computer experiments strategy was used for generating a set of observational data that contains the maximum wall shear stress values for a range of probable arterial geometries. The dataset was mined via a Bayesian Gaussian process emulator to estimate: (a the influence of key parameters on the output via sensitivity analysis, (b uncertainty in output as a function of uncertainty in input, and (c which settings of the input parameters result in maximum and minimum values of the output. Finally, potential diagnostic indicators were proposed that can be used to aid the assessment of stroke risk for a given patient's geometry.

  19. Soil macropores: Control on infiltration, hillslope and surface hydrology on a reclaimed surface-mined watershed

    International Nuclear Information System (INIS)

    Guebert, M.D.; Gardner, T.W.

    1992-01-01

    The hydrologic response of a surface-mined watershed in central Pennsylvania is controlled by rapid macropore flow within the unsaturated man-made topsoil. Newly reclaimed surface-mined watersheds in central Pennsylvania exhibit low steady-state infiltration rates (1--2 cm/hr) and produce runoff dominated by infiltration-excess overland flow. However, within four years after reclamation, infiltration rates on some mine surfaces approach premined rates (8 cm/hr). As infiltration rate increases, the volume of infiltrated water increases, but the total porosity of minesoil matrix remains constant. There is little change in the surface discharge volume, indicating that infiltrated water continues to contribute to the basin surface discharge by the processes of throughflow and return flow. Throughflow in the topsoil horizon occurs in rapid response to rainfall input, producing large volumes of water with throughflow rates closely related to rainfall rates and with throughflow peaks following rainfall peaks by only minutes. Increased return flow alters the shape of the surface runoff hydrograph by slightly lagging behind infiltration excess overland flow. These changes in the shape of the surface runoff hydrograph reduce the potential for severe gully erosion on the reclaimed site. In addition, throughflow water remains predominantly in the topsoil horizon, and therefore has limited contact with potentially acid-producing backfill. Better understanding of macropore flow processes in reclaimed minesoils will help investigators evaluate past strategies and develop new reclamation techniques that will minimize the short-term surface erosional effects of mining and reclamation, while optimizing the long-term effluent and groundwater quality

  20. 30 CFR 941.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE SOUTH DAKOTA § 941.761 Areas designated unsuitable for surface coal mining by act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  1. 30 CFR 937.761 - Areas designated unsuitable for surface coal mining by Act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE OREGON § 937.761 Areas designated unsuitable for surface coal mining by Act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining and... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  2. 30 CFR 905.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE CALIFORNIA § 905.761 Areas designated unsuitable for surface coal mining by act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  3. 30 CFR 910.761 - Areas designated unsuitable for surface coal mining by Act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE GEORGIA § 910.761 Areas designated unsuitable for surface coal mining by Act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  4. 30 CFR 903.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE ARIZONA § 903.761 Areas designated unsuitable for surface coal mining by act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, applies to surface coal mining... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  5. 30 CFR 939.761 - Areas designated unsuitable for surface coal mining by Act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE RHODE ISLAND § 939.761 Areas designated unsuitable for surface coal mining by Act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  6. 30 CFR 922.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE MICHIGAN § 922.761 Areas designated unsuitable for surface coal mining by act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  7. 30 CFR 921.761 - Areas designated unsuitable for surface coal mining by Act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE MASSACHUSETTS § 921.761 Areas designated unsuitable for surface coal mining by Act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  8. 30 CFR 912.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE IDAHO § 912.761 Areas designated unsuitable for surface coal mining by act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining and... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  9. 30 CFR 947.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE WASHINGTON § 947.761 Areas designated unsuitable for surface coal mining by act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  10. 30 CFR 942.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... WITHIN EACH STATE TENNESSEE § 942.761 Areas designated unsuitable for surface coal mining by act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal...

  11. 43 CFR 20.402 - Interests in underground or surface coal mining operations.

    Science.gov (United States)

    2010-10-01

    ... Certain Employees of the Department § 20.402 Interests in underground or surface coal mining operations...) Indirect financial interest in underground or surface coal mining operations means the same financial... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Interests in underground or surface coal...

  12. Impacts of surface gold mining on land use systems in Western Ghana.

    Science.gov (United States)

    Schueler, Vivian; Kuemmerle, Tobias; Schröder, Hilmar

    2011-07-01

    Land use conflicts are becoming increasingly apparent from local to global scales. Surface gold mining is an extreme source of such a conflict, but mining impacts on local livelihoods often remain unclear. Our goal here was to assess land cover change due to gold surface mining in Western Ghana, one of the world's leading gold mining regions, and to study how these changes affected land use systems. We used Landsat satellite images from 1986-2002 to map land cover change and field interviews with farmers to understand the livelihood implications of mining-related land cover change. Our results showed that surface mining resulted in deforestation (58%), a substantial loss of farmland (45%) within mining concessions, and widespread spill-over effects as relocated farmers expand farmland into forests. This points to rapidly eroding livelihood foundations, suggesting that the environmental and social costs of Ghana's gold boom may be much higher than previously thought.

  13. Numerical simulation of a multi-reef tabular mining layout in a South African platinum mine

    CSIR Research Space (South Africa)

    Napier, JAL

    2008-09-01

    Full Text Available Some of the key problems facing rock engineers on mines in the Bushveld Complex are design of stable panel spans, optimum pillar dimensions and assessing hangingwall stability. A particularly difficult problem is encountered in some mines where...

  14. Hydrochemical characteristics of mine waters from abandoned mining sites in Serbia and their impact on surface water quality.

    Science.gov (United States)

    Atanacković, Nebojša; Dragišić, Veselin; Stojković, Jana; Papić, Petar; Zivanović, Vladimir

    2013-11-01

    Upon completion of exploration and extraction of mineral resources, many mining sites have been abandoned without previously putting environmental protection measures in place. As a consequence, mine waters originating from such sites are discharged freely into surface water. Regional scale analyses were conducted to determine the hydrochemical characteristics of mine waters from abandoned sites featuring metal (Cu, Pb-Zn, Au, Fe, Sb, Mo, Bi, Hg) deposits, non-metallic minerals (coal, Mg, F, B) and uranium. The study included 80 mine water samples from 59 abandoned mining sites. Their cation composition was dominated by Ca2+, while the most common anions were found to be SO4(2-) and HCO3-. Strong correlations were established between the pH level and metal (Fe, Mn, Zn, Cu) concentrations in the mine waters. Hierarchical cluster analysis was applied to parameters generally indicative of pollution, such as pH, TDS, SO4(2-), Fe total, and As total. Following this approach, mine water samples were grouped into three main clusters and six subclusters, depending on their potential environmental impact. Principal component analysis was used to group together variables that share the same variance. The extracted principal components indicated that sulfide oxidation and weathering of silicate and carbonate rocks were the primary processes, while pH buffering, adsorption and ion exchange were secondary drivers of the chemical composition of the analyzed mine waters. Surface waters, which received the mine waters, were examined. Analysis showed increases of sulfate and metal concentrations and general degradation of surface water quality.

  15. Assessing Surface Hydrological Processes on a Rehabilitated Mine Landform in Northern Australia

    Science.gov (United States)

    Shao, Qi; Saynor, Mike; Lowry, John; Lu, Ping; Baumgartl, Thomas

    2015-04-01

    To assist with the evaluation of the proposed rehabilitation designs for the mine closure at a Uranium Mine, Northern Territory, Australia, a trial landform (200 m × 400 m) was constructed using waste rocks, with its surface ripped along the contour. The surface hydrological performance of this landform was investigated in this study. Field infiltration measurements were conducted using both large and regular ring infiltrometers to investigate the surface hydraulic properties, and water contents and surface runoff were monitored continuously in two 30 m × 30 m runoff plots for four years. A Cellular Automata based runoff model (RunCA) was also used to simulate the runoff behaviors under different rainfall conditions. Results showed a higher infiltration capacity in the areas of rip lines than the non-ripped areas due to the disturbance to the surface. Runoff coefficient was less than 6% and 10% for 80% of the 304 observed rainfall events on plot 1 and plot 2, respectively. The low levels of runoff were well explained by the simulated flow maps of RunCA, which demonstrated the roles of the rip lines in storing flow water and discontinuing the runoff paths. However, when the maximum storage capacity of these rip lines was exceeded during several large rainfall events, the runoff became much more significant and led to high potentials for erosion and landform instability. RunCA simulations on the virtual landforms with higher rip lines indicated dramatically reduced runoff rates. Therefore, it is suggested here that the current landform may be subjected to great runoff and erosion risks under extreme rainfall events, and raising the rip line height may potentially solve this problem.

  16. Project proposal for surface-mined land enhancement (SMILE)

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, A.M.

    1975-01-29

    Reclaiming strip-mined land is a program ideally suited to meet the requirements of the Job Opportunities Program. It will provide healthy and vigorous outdoor activity involving surveying, earth-moving, revegetation, tree planting, construction of roads, paths, lakes, and park facilities. It is work which states and communities are anxious to have started. It can be done with relatively small capital expenditure. Technical expertise is available in the various states concerned. FEA is the ideal agency to initiate such a project. It has regional offices throughout the country with close contacts with states and local communities. It is a temporary emergency agency with considerable experience in initiating and carrying out crash programs. It is not tied down to the procedures and bureaucratic problems which burden an old-line agency attempting to take on new work. Finally, FEA has a vital interest in energy and surface mining in particular. It played a major role in drafting the new legislation. The initial program development is described, including the technical aspects, economic aspects and administration, cost, budget, cooperation with state agencies, etc.

  17. Finite element modeling of surface subsidence induced by underground coal mining

    International Nuclear Information System (INIS)

    Su, D.W.H.

    1992-01-01

    The ability to predict the effects of longwall mining on topography and surface structures is important for any coal company in making permit applications and anticipating potential mining problems. The sophisticated finite element model described and evaluated in this paper is based upon five years of underground and surface observations and evolutionary development of modeling techniques and attributes. The model provides a very powerful tool to address subsidence and other ground control questions. The model can be used to calculate postmining stress and strain conditions at any horizon between the mine and the ground surface. This holds the promise of assisting in the prediction of mining-related hydrological effects

  18. Microarray data and gene expression statistics for Saccharomyces cerevisiae exposed to simulated asbestos mine drainage

    Directory of Open Access Journals (Sweden)

    Heather E. Driscoll

    2017-08-01

    Full Text Available Here we describe microarray expression data (raw and normalized, experimental metadata, and gene-level data with expression statistics from Saccharomyces cerevisiae exposed to simulated asbestos mine drainage from the Vermont Asbestos Group (VAG Mine on Belvidere Mountain in northern Vermont, USA. For nearly 100 years (between the late 1890s and 1993, chrysotile asbestos fibers were extracted from serpentinized ultramafic rock at the VAG Mine for use in construction and manufacturing industries. Studies have shown that water courses and streambeds nearby have become contaminated with asbestos mine tailings runoff, including elevated levels of magnesium, nickel, chromium, and arsenic, elevated pH, and chrysotile asbestos-laden mine tailings, due to leaching and gradual erosion of massive piles of mine waste covering approximately 9 km2. We exposed yeast to simulated VAG Mine tailings leachate to help gain insight on how eukaryotic cells exposed to VAG Mine drainage may respond in the mine environment. Affymetrix GeneChip® Yeast Genome 2.0 Arrays were utilized to assess gene expression after 24-h exposure to simulated VAG Mine tailings runoff. The chemistry of mine-tailings leachate, mine-tailings leachate plus yeast extract peptone dextrose media, and control yeast extract peptone dextrose media is also reported. To our knowledge this is the first dataset to assess global gene expression patterns in a eukaryotic model system simulating asbestos mine tailings runoff exposure. Raw and normalized gene expression data are accessible through the National Center for Biotechnology Information Gene Expression Omnibus (NCBI GEO Database Series GSE89875 (https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE89875.

  19. Simulation of California's Major Reservoirs Outflow Using Data Mining Technique

    Science.gov (United States)

    Yang, T.; Gao, X.; Sorooshian, S.

    2014-12-01

    The reservoir's outflow is controlled by reservoir operators, which is different from the upstream inflow. The outflow is more important than the reservoir's inflow for the downstream water users. In order to simulate the complicated reservoir operation and extract the outflow decision making patterns for California's 12 major reservoirs, we build a data-driven, computer-based ("artificial intelligent") reservoir decision making tool, using decision regression and classification tree approach. This is a well-developed statistical and graphical modeling methodology in the field of data mining. A shuffled cross validation approach is also employed to extract the outflow decision making patterns and rules based on the selected decision variables (inflow amount, precipitation, timing, water type year etc.). To show the accuracy of the model, a verification study is carried out comparing the model-generated outflow decisions ("artificial intelligent" decisions) with that made by reservoir operators (human decisions). The simulation results show that the machine-generated outflow decisions are very similar to the real reservoir operators' decisions. This conclusion is based on statistical evaluations using the Nash-Sutcliffe test. The proposed model is able to detect the most influential variables and their weights when the reservoir operators make an outflow decision. While the proposed approach was firstly applied and tested on California's 12 major reservoirs, the method is universally adaptable to other reservoir systems.

  20. 3D modeling of surface quarries and deposits of mined materials and the monitoring of slopes

    Directory of Open Access Journals (Sweden)

    Ivan Maňas

    2007-06-01

    Full Text Available The application of computer technology by simulating opencast mining and deposits of raw materials. The mathematic principles of three-dimensional probabilistic models of raw materials deposits and a familiarization with the user interface software GEOLOGICKY MODEL. The principles of the simulation of opencast mines, generation intersections with models of raw materials deposits, computation of mining materials with the quality scaling,and the design of advanced mining with the software BANSKY MODEL.The monitoring the potential of dynamic movements’ of unstable slopes with the automatic total station and a following interpretation in general time intervals by means of the software MONITORING.

  1. Usage of emulsion explosives on surface open pit mine “Zelenikovec” - Skopje

    OpenAIRE

    Dambov, Risto; Bosevski, Trajce

    2013-01-01

    This paper describes the advantages of using emulsion explosives on the surface mine ”Zelenikovec”. A comparison has been made with the other types of explosives regarding the cost of drilling, blasting, environmental protection and the safety while using them. In the estimates, the criteria for using this type of emulsion explosives on the surface mine “Zelenikovec” have been met.

  2. 30 CFR 57.4131 - Surface fan installations and mine openings.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Surface fan installations and mine openings. 57... Fire Prevention and Control Prohibitions/precautions/housekeeping § 57.4131 Surface fan installations... stored within 100 feet of mine openings or within 100 feet of fan installations used for underground...

  3. Quartz exposure levels in the underground and surface coal mining industry

    Energy Technology Data Exchange (ETDEWEB)

    Ainsworth, S.M.; Gero, A.J.; Parobeck, P.S; Tomb, T.F. [US Mine Safety and Health Administration, Pittsburgh, PA (United States)

    1995-10-01

    Occupational quartz exposure data gathered from the Mine Safety and Health Adminsitration`s respirable dust enforcement program and a program to monitor quartz exposure in several mining occupations were compiled and analyzed to assess the status of quartz exposures in the coal mining industry. The analysis showed that, in underground mines, a substantial number of samples contained greater than 5% quartz. Occupations that showed a high frequency of excessive quartz exposure included the roof bolter, continuous miner operator, and continuous miner operator helper. In surface coal mines the highwall drill operator and helper, bulldozer operator, scraper operator, and truck driver were frequently exposed to high quartz concentrations.

  4. LANDSAT remote sensing: observations of an Appalachian mountaintop surface coal mining and reclamation operation

    International Nuclear Information System (INIS)

    1979-10-01

    The potential benefits of using LANDSAT remote sensing data by state agencies as an aide in monitoring surface coal mining operations are reviewed. A mountaintop surface mine in eastern Kentucky was surveyed over a 5 year period using satellite multispectral scanner data that were classified by computer analyses. The analyses were guided by aerial photography and by ground surveys of the surface mines procured in 1976. The application of the LANDSAT data indicates that: (1) computer classification of the various landcover categories provides information for monitoring the progress of surface mining and reclamation operations, (2) successive yearly changes in barren and revegetated areas can be qualitatively assessed for surface mines of 100 acres or more of disrupted area, (3) barren areas consisting of limestone and shale mixtures may be recognized, and revegetated areas in various stages of growth may be identified against the hilly forest background

  5. Use of modflow drain package for simulating inter-basin transfer in abandoned coal mines

    Science.gov (United States)

    Kozar, Mark D.; McCoy, Kurt J.

    2017-01-01

    Simulation of groundwater flow in abandoned mines is difficult, especially where flux to and from mines is unknown or poorly quantified, and inter-basin transfer of groundwater occurs. A 3-year study was conducted in the Elkhorn area, West Virginia to better understand groundwater-flow processes and inter-basin transfer in above drainage abandoned coal mines. The study area was specifically selected, as all mines are located above the elevation of tributary receiving streams, to allow accurate measurements of discharge from mine portals and tributaries for groundwater model calibration. Abandoned mine workings were simulated in several ways, initially as a layer of high hydraulic conductivity bounded by lower permeability rock in adjacent strata, and secondly as rows of higher hydraulic conductivity embedded within a lower hydraulic conductivity coal aquifer matrix. Regardless of the hydraulic conductivity assigned to mine workings, neither approach to simulate mine workings could accurately reproduce the inter-basin transfer of groundwater from adjacent watersheds. To resolve the problem, a third approach was developed. The MODFLOW DRAIN package was used to simulate seepage into and through mine workings discharging water under unconfined conditions to Elkhorn Creek, North Fork, and tributaries of the Bluestone River. Drain nodes were embedded in a matrix of uniform hydraulic conductivity cells that represented the coal mine aquifer. Drain heads were empirically defined from well observations, and elevations were based on structure contours for the Pocahontas No. 3 mine workings. Use of the DRAIN package to simulate mine workings as an internal boundary condition resolved the inter-basin transfer problem, and effectively simulated a shift from a topographic- dominated to a dip-dominated flow system, by dewatering overlying unmined strata and shifting the groundwater drainage divide up dip within the Pocahontas No. 3 coal seam several kilometers into the adjacent

  6. In Vitro Studies Evaluating Leaching of Mercury from Mine Waste Calcine Using Simulated Human Body Fluids

    OpenAIRE

    Gray, John E.; Plumlee, Geoffrey S.; Morman, Suzette A.; Higueras, Pablo L.; Crock, James G.; Lowers, Heather A.; Witten, Mark L.

    2010-01-01

    In vitro bioaccessibility (IVBA) studies were carried out on samples of mercury (Hg) mine-waste calcine (roasted Hg ore) by leaching with simulated human body fluids. The objective was to estimate potential human exposure to Hg due to inhalation of airborne calcine particulates and hand-to-mouth ingestion of Hg-bearing calcines. Mine waste calcines collected from Hg mines at Almad?n, Spain, and Terlingua, Texas, contain Hg sulfide, elemental Hg, and soluble Hg compounds, which constitute prim...

  7. Simulation of land mine detection processes using nuclear techniques

    International Nuclear Information System (INIS)

    Aziz, M.

    2005-01-01

    A computer models were designed to study the processes of land mine detection using nuclear technique. Parameters that affect the detection were analyzed . Mines of different masses at different depths in the soil are considered using two types of sources , 252 C f and 14 MeV neutron source. The capability to differentiate between mines and other objects such as concrete , iron , wood , Aluminum ,water and polyethylene were analyzed and studied

  8. Woody vegetation and succession on the Fonde surface mine demonstration area, Bell County, Kentucky

    International Nuclear Information System (INIS)

    Wade, G.L.; Thompson, R.L.

    1999-01-01

    The long term impact of surface mining on vegetation and plant succession has always been of concern to environmentalists and residents of Appalachia. The Fonde Surface Mine Demonstration Area is a 7.3-ha, NE-NW-aspect contour coal mine at an elevation of 562 m. It was reclaimed in 1965 to show state-of-the-art surface mine reclamation techniques consistent with then-current law and regulations after coal mining in 1959 and 1963. The mine spoils were lightly graded to control erosion and crates a bench with water control and two sediment ponds. Soil pH ranged from 2.8 to 5.9. About 80 percent of the mine was planted with 18 tree and shrub species including plantations of mixed pine, mixed hardwoods, black locust, and shrubs for wildlife. In a complete floristic inventory conducted 25 years later, the authors found the woody flora consisted of 34 families, 53 genera, and 70 species including 7 exotics. This inventory of the Fonde mine shows that a diverse forest vegetation can be reestablished after extreme disturbances in Appalachia. Black locust, yellow poplar, and Virginia pine reproduction varied significantly among plantation types. Canopy tree species significantly affected ground layer cover, total species richness, number of tree seedling species, and total number of tree seedlings present. Mine soil type affected ground layer percent cover and total species richness. Pre-SMCRA (Surface Mining Control and Reclamation Act of 1977) reclaimed and inventoried mines can be used to evaluate biodiversity on post-SMCRA mines

  9. Restoring forests and associated ecosystem services on appalachian coal surface mines.

    Science.gov (United States)

    Zipper, Carl E; Burger, James A; Skousen, Jeffrey G; Angel, Patrick N; Barton, Christopher D; Davis, Victor; Franklin, Jennifer A

    2011-05-01

    Surface coal mining in Appalachia has caused extensive replacement of forest with non-forested land cover, much of which is unmanaged and unproductive. Although forested ecosystems are valued by society for both marketable products and ecosystem services, forests have not been restored on most Appalachian mined lands because traditional reclamation practices, encouraged by regulatory policies, created conditions poorly suited for reforestation. Reclamation scientists have studied productive forests growing on older mine sites, established forest vegetation experimentally on recent mines, and identified mine reclamation practices that encourage forest vegetation re-establishment. Based on these findings, they developed a Forestry Reclamation Approach (FRA) that can be employed by coal mining firms to restore forest vegetation. Scientists and mine regulators, working collaboratively, have communicated the FRA to the coal industry and to regulatory enforcement personnel. Today, the FRA is used routinely by many coal mining firms, and thousands of mined hectares have been reclaimed to restore productive mine soils and planted with native forest trees. Reclamation of coal mines using the FRA is expected to restore these lands' capabilities to provide forest-based ecosystem services, such as wood production, atmospheric carbon sequestration, wildlife habitat, watershed protection, and water quality protection to a greater extent than conventional reclamation practices.

  10. Restoring Forests and Associated Ecosystem Services on Appalachian Coal Surface Mines

    Science.gov (United States)

    Zipper, Carl E.; Burger, James A.; Skousen, Jeffrey G.; Angel, Patrick N.; Barton, Christopher D.; Davis, Victor; Franklin, Jennifer A.

    2011-05-01

    Surface coal mining in Appalachia has caused extensive replacement of forest with non-forested land cover, much of which is unmanaged and unproductive. Although forested ecosystems are valued by society for both marketable products and ecosystem services, forests have not been restored on most Appalachian mined lands because traditional reclamation practices, encouraged by regulatory policies, created conditions poorly suited for reforestation. Reclamation scientists have studied productive forests growing on older mine sites, established forest vegetation experimentally on recent mines, and identified mine reclamation practices that encourage forest vegetation re-establishment. Based on these findings, they developed a Forestry Reclamation Approach (FRA) that can be employed by coal mining firms to restore forest vegetation. Scientists and mine regulators, working collaboratively, have communicated the FRA to the coal industry and to regulatory enforcement personnel. Today, the FRA is used routinely by many coal mining firms, and thousands of mined hectares have been reclaimed to restore productive mine soils and planted with native forest trees. Reclamation of coal mines using the FRA is expected to restore these lands' capabilities to provide forest-based ecosystem services, such as wood production, atmospheric carbon sequestration, wildlife habitat, watershed protection, and water quality protection to a greater extent than conventional reclamation practices.

  11. Simulation of Gas-Surface Dynamical Interactions

    Science.gov (United States)

    2007-07-01

    surface. The substrate with lattice constant a is represented in a simple ball and spring picture. on the particular problem. Time-independent...παvwell , (26) Simulation of Gas-Surface Dynamical Interactions 4 - 10 RTO-EN-AVT-142 g E ad v mvc ∆ v’well vc cM Figure 4

  12. Modelling and simulation of surface water waves

    NARCIS (Netherlands)

    van Groesen, Embrecht W.C.; Westhuis, J.H.

    2002-01-01

    The evolution of waves on the surface of a layer of fluid is governed by non-linear effects from surface deformations and dispersive effects from the interaction with the interior fluid motion. Several simulation tools are described in this paper and compared with real life experiments in large

  13. Simulation Tool for GNSS Ocean Surface Reflections

    DEFF Research Database (Denmark)

    Høeg, Per; von Benzon, Hans-Henrik; Durgonics, Tibor

    2015-01-01

    . This impedance concept gives an accurate lower boundary condition in the determination of the electromagnetic field, and makes itpossible to simulate reflections and the effects of transitions between different mediums. A semi-isotropic Philipsspectrum is used to represent the air-sea interaction.Simulated GPS...... on the solution of the parabolic equation. The parabolic equation in our simulator is solvedusing the split-step sine transformation. The Earth’s surface is modeled with the use of an impedance model. The value of the Earth impedance is given as a function of the range along the surface of the Earth...

  14. Building Airport Surface HITL Simulation Capability

    Science.gov (United States)

    Chinn, Fay Cherie

    2016-01-01

    FutureFlight Central is a high fidelity, real-time simulator designed to study surface operations and automation. As an air traffic control tower simulator, FFC allows stakeholders such as the FAA, controllers, pilots, airports, and airlines to develop and test advanced surface and terminal area concepts and automation including NextGen and beyond automation concepts and tools. These technologies will improve the safety, capacity and environmental issues facing the National Airspace system. FFC also has extensive video streaming capabilities, which combined with the 3-D database capability makes the facility ideal for any research needing an immersive virtual and or video environment. FutureFlight Central allows human in the loop testing which accommodates human interactions and errors giving a more complete picture than fast time simulations. This presentation describes FFCs capabilities and the components necessary to build an airport surface human in the loop simulation capability.

  15. Atlas of western surface-mined lands: coal, uranium, and phosphate

    International Nuclear Information System (INIS)

    Evans, A.K.; Uhleman, E.W.; Eby, P.A.

    1978-01-01

    The atlas contains available information on all coal, uranium, and phosphate surface mines in excess of 10 acres that were in operation prior to 1976 in the western 11 contiguous states plus North Dakota and South Dakota. It is assembled in a format that allows a systematic and comprehensive review of surface-mined lands so that appropriate areas can be selected for intensive biological assessment of natural and man-induced revegetation and refaunation. For each identified mine, the following information has been obtained wherever possible: geographic location and locating instructions, operator and surface and subsurface ownership, summary of the mining plan and methods, summary of the reclamation plan and methods, dates of operation, area affected by mining activities, reclamation history, where applicable, and current land use and vegetation conditions

  16. Large Omnivore Movements in Response to Surface Mining and Mine Reclamation.

    Science.gov (United States)

    Cristescu, Bogdan; Stenhouse, Gordon B; Boyce, Mark S

    2016-01-11

    Increasing global demands have resulted in widespread proliferation of resource extraction. Scientists are challenged to develop environmental mitigation strategies that meet societal expectations of resource supply, while achieving minimal disruption to sensitive "wilderness" species. We used GPS collar data from a 9-year study on grizzly bears (Ursus arctos) (n = 18) in Alberta, Canada to assess movements and associated space use during versus after mining. Grizzly bear home range overlap with mined areas was lower during active mining except for females with cubs, that also had shortest movements on active mines. However, both females with cubs and males made shorter steps when on/close to mines following mine closure and reclamation. Our results show differences in bear movement and space-use strategies, with individuals from a key population segment (females with cubs) appearing most adaptable to mining disturbance. Preserving patches of original habitat, reclaiming the landscape and minimizing the risk of direct human-induced mortality during and after development can help conserve bears and other wildlife on industrially modified landscapes.

  17. Numerical simulation of phenomenon on zonal disintegration in deep underground mining in case of unsupported roadway

    Science.gov (United States)

    Han, Fengshan; Wu, Xinli; Li, Xia; Zhu, Dekang

    2018-02-01

    Zonal disintegration phenomenon was found in deep mining roadway surrounding rock. It seriously affects the safety of mining and underground engineering and it may lead to the occurrence of natural disasters. in deep mining roadway surrounding rock, tectonic stress in deep mining roadway rock mass, horizontal stress is much greater than the vertical stress, When the direction of maximum principal stress is parallel to the axis of the roadway in deep mining, this is the main reasons for Zonal disintegration phenomenon. Using ABAQUS software to numerical simulation of the three-dimensional model of roadway rupture formation process systematically, and the study shows that when The Direction of maximum main stress in deep underground mining is along the roadway axial direction, Zonal disintegration phenomenon in deep underground mining is successfully reproduced by our numerical simulation..numerical simulation shows that using ABAQUA simulation can reproduce Zonal disintegration phenomenon and the formation process of damage of surrounding rock can be reproduced. which have important engineering practical significance.

  18. IDENTIFYING RECENT SURFACE MINING ACTIVITIES USING A NORMALIZED DIFFERENCE VEGETATION INDEX (NDVI) CHANGE DETECTION METHOD

    Science.gov (United States)

    Coal mining is a major resource extraction activity on the Appalachian Mountains. The increased size and frequency of a specific type of surface mining, known as mountain top removal-valley fill, has in recent years raised various environmental concerns. During mountainto...

  19. Biological responses to disturbance from simulated deep-sea polymetallic nodule mining.

    Directory of Open Access Journals (Sweden)

    Daniel O B Jones

    Full Text Available Commercial-scale mining for polymetallic nodules could have a major impact on the deep-sea environment, but the effects of these mining activities on deep-sea ecosystems are very poorly known. The first commercial test mining for polymetallic nodules was carried out in 1970. Since then a number of small-scale commercial test mining or scientific disturbance studies have been carried out. Here we evaluate changes in faunal densities and diversity of benthic communities measured in response to these 11 simulated or test nodule mining disturbances using meta-analysis techniques. We find that impacts are often severe immediately after mining, with major negative changes in density and diversity of most groups occurring. However, in some cases, the mobile fauna and small-sized fauna experienced less negative impacts over the longer term. At seven sites in the Pacific, multiple surveys assessed recovery in fauna over periods of up to 26 years. Almost all studies show some recovery in faunal density and diversity for meiofauna and mobile megafauna, often within one year. However, very few faunal groups return to baseline or control conditions after two decades. The effects of polymetallic nodule mining are likely to be long term. Our analyses show considerable negative biological effects of seafloor nodule mining, even at the small scale of test mining experiments, although there is variation in sensitivity amongst organisms of different sizes and functional groups, which have important implications for ecosystem responses. Unfortunately, many past studies have limitations that reduce their effectiveness in determining responses. We provide recommendations to improve future mining impact test studies. Further research to assess the effects of test-mining activities will inform ways to improve mining practices and guide effective environmental management of mining activities.

  20. Recent developments in the reclamation of surface mined lands

    Science.gov (United States)

    Sharma, K.D.; Gough, L.P.; Kumar, S.; Sharma, B.K.; Saxena, S.K.

    1997-01-01

    A broad review of mine land reclamation problems and challenges in arid lands is presented with special emphasis on work recently completed in India. The economics of mining in the Indian Desert is second only to agriculture in importance. Lands disturbed by mining, however, have only recently been the focus of reclamation attempts. Studies were made and results compiled of problems associated with germplasm selection, soil, plant and overburden characterization and manipulation, plant establishment methods utilized, soil amendment needs, use and conservation of available water and the evaluation of ecosystem sustainability. Emphasis is made of the need for multi-disciplinary approaches to mine land reclamation research and for the long-term monitoring of reclamation success.

  1. Effect of high-extraction coal mining on surface and ground waters

    International Nuclear Information System (INIS)

    Kendorski, F.S.

    1993-01-01

    Since first quantified around 1979, much new data have become available. In examining the sources of data and the methods and intents of the researchers of over 65 case histories, it became apparent that the strata behaviors were being confused with overlapping vertical extents reported for the fractured zones and aquiclude zones depending on whether the researcher was interested in water intrusion into the mine or in water loss from surface or ground waters. These more recent data, and critical examination of existing data, have led to the realization that the former Aquiclude Zone defined for its ability to prevent or minimize the intrusion of ground or surface waters into mines has another important character in increasing storage of surface and shallow ground waters in response to mining with no permanent loss of waters. This zone is here named the Dilated Zone. Surface and ground waters can drain into this zone, but seldom into the mine, and can eventually be recovered through closing of dilations by mine subsidence progression away from the area, or filling of the additional void space created, or both. A revised model has been developed which accommodates the available data, by modifying the zones as follows: collapse and disaggregation extending 6 to 10 times the mined thickness above the panel; continuous fracturing extending approximately 24 times the mined thickness above the panel, allowing temporary drainage of intersected surface and ground waters; development of a zone of dilated, increased storativity, and leaky strata with little enhanced vertical permeability from 24 to 60 times the mined thickness above the panel above the continuous fracturing zone, and below the constrained or surface effects zones; maintenance of a constrained but leaky zone above the dilated zone and below the surface effects zone; and limited surface fracturing in areas of extension extending up to 50 ft or so beneath the ground surface. 119 ref., 5 figs., 2 tabs

  2. NEWS RELEASE - Agencies Agree to Joint Regulatory Framework for Processing Applications for Surface Coal Mining Operations

    Science.gov (United States)

    News release from February 10, 2005 announcing a memorandum of understanding (MOU) that offers a joint framework to improve permit application procedures for surface coal mining operations that place dredged or fill material in waters of the United States.

  3. Rehabilitation materials from surface- coal mines in western U.S.A. III. Relations between elements in mine soil and uptake by plants.

    Science.gov (United States)

    Severson, R.C.; Gough, L.P.

    1984-01-01

    Plant uptake of Cd, Co, Cu, Fe, Mn, Ni, Pb and Zn from mine soils was assessed using alfalfa Medicago sativa, sainfoin Onobrychis viciaefolia, smooth brome Bromus inermis, crested wheatgrass Agropyron cristatum, slender wheatgrass A. trachycaulum and intermediate wheatgrass A. intermedium; mine soil (cover-soil and spoil material) samples were collected from rehabilitated areas of 11 western US surface-coal mines in North Dakota, Montana, Wyoming and Colorado. Correlations between metals in plants and DTPA-extractable metals from mine soils were generally not statistically significant and showed no consistent patterns for a single metal or for a single plant species. Metal uptake by plants, relative to amounts in DTPA extracts of mine soil, was positively related to mine soil organic matter content or negatively related to mine soil pH. DTPA-extractable metal levels were significantly correlated with mine soil pH and organic-matter content.-from Authors

  4. Molecular Dynamics Simulations for Predicting Surface Wetting

    Directory of Open Access Journals (Sweden)

    Jing Chen

    2014-06-01

    Full Text Available The investigation of wetting of a solid surface by a liquid provides important insights; the contact angle of a liquid droplet on a surface provides a quantitative measurement of this interaction and the degree of attraction or repulsion of that liquid type by the solid surface. Molecular dynamics (MD simulations are a useful way to examine the behavior of liquids on solid surfaces on a nanometer scale. Thus, we surveyed the state of this field, beginning with the fundamentals of wetting calculations to an examination of the different MD methodologies used. We highlighted some of the advantages and disadvantages of the simulations, and look to the future of computer modeling to understand wetting and other liquid-solid interaction phenomena.

  5. 78 FR 63463 - Intent To Prepare a Regional Environmental Impact Statement for Surface Coal and Lignite Mining...

    Science.gov (United States)

    2013-10-24

    ... Environmental Impact Statement for Surface Coal and Lignite Mining in the State of Texas AGENCY: Department of... responsibility. These coal and lignite mining activities may eventually require authorization from the USACE... by mail. Surface coal and lignite mining projects in the USACE Fort Worth's area of responsibility...

  6. 75 FR 18500 - Guidance on Improving EPA Review of Appalachian Surface Coal Mining Operations under the Clean...

    Science.gov (United States)

    2010-04-12

    ... in terms of mine design, site and materials management, or water treatment systems, consistent with... of Appalachian Surface Coal Mining Operations under the Clean Water Act, National Environmental... Appalachian Surface Coal Mining Operations under the Clean Water Act, National Environmental Policy Act, and...

  7. Development of a tree classifier for discrimination of surface mine activity from Landsat digital data

    Science.gov (United States)

    Solomon, J. L.; Miller, W. F.; Quattrochi, D. A.

    1979-01-01

    In a cooperative project with the Geological Survey of Alabama, the Mississippi State Remote Sensing Applications Program has developed a single purpose, decision-tree classifier using band-ratioing techniques to discriminate various stages of surface mining activity. The tree classifier has four levels and employs only two channels in classification at each level. An accurate computation of the amount of disturbed land resulting from the mining activity can be made as a product of the classification output. The utilization of Landsat data provides a cost-efficient, rapid, and accurate means of monitoring surface mining activities.

  8. The politics of space mining - An account of a simulation game

    Science.gov (United States)

    Paikowsky, Deganit; Tzezana, Roey

    2018-01-01

    Celestial bodies like the Moon and asteroids contain materials and precious metals, which are valuable for human activity on Earth and beyond. Space mining has been mainly relegated to the realm of science fiction, and was not treated seriously by the international community. The private industry is starting to assemble towards space mining, and success on this front would have major impact on all nations. We present in this paper a review of current space mining ventures, and the international legislation, which could stand in their way - or aid them in their mission. Following that, we present the results of a role-playing simulation in which the role of several important nations was played by students of international relations. The results of the simulation are used as a basis for forecasting the potential initial responses of the nations of the world to a successful space mining operation in the future.

  9. Airborne Lidar Surface Topography (LIST) Simulator

    Science.gov (United States)

    Yu, Anthony W.; Krainak, Michael A.; Harding, David J.; Abshire, James B.; Sun, Xiaoli; Cavanaugh, John; Valett, Susan; Ramos-Izquierdo, Luis; Winkert, Tom; Plants, Michael; hide

    2011-01-01

    In this paper we will discuss our development effort of an airborne instrument as a pathfinder for the Lidar Surface Technology (LIST) mission. This paper will discuss the system approach, enabling technologies, instrument concept and performance of the Airborne LIST Simulator (A-LISTS).

  10. Application of Discrete EventSimulation in Mine Production Forecast*

    African Journals Online (AJOL)

    Michael

    2016-06-01

    Jun 1, 2016 ... animation of the system in Arena®. The various activities of the shovel-truck system were animated to ensure the visualisation of the whole operations of the mine with respect to the AG pit. A digital terrain model (DTM) representing AG pit was imported into Arena® for further drawings of haul roads, dumps ...

  11. A Simulator to Enhance Teaching and Learning of Mining Methods ...

    African Journals Online (AJOL)

    Audio visual education that incorporates devices and materials which involve sight, sound, or both has become a sine qua non in recent times in the teaching and learning process. An automated physical model of mining methods aided with video instructions was designed and constructed by harnessing locally available ...

  12. Nuclear waste repository simulation experiments, Asse Salt Mine, Federal Republic of Germany. Annual report, 1983

    International Nuclear Information System (INIS)

    Rothfuchs, T.; Luebker, D.; Coyle, A.; Kalia, H.

    1984-10-01

    This is the First Annual report (1983) which describes experiments simulating a nuclear waste respository at the 800-meter level of the Asse Salt Mine in the Federal Republic of Germany. The report describes the test equipment, the Asse Salt Mine, the pretest properties of the salt in the test gallery, and the mine proper. Also included are test data for the first six months of operations on brine migration rates, room closure rates, extensometer readings, stress measurements, and thermal mechanical behavior of the salt. The duration of the experiments will be two years, ending in December 1985. 3 references, 34 figures, 13 tables

  13. Effect of traditional gold mining to surface water quality in Murung Raya District, Central Kalimantan Province

    Directory of Open Access Journals (Sweden)

    W.Wilopo

    2013-10-01

    Full Text Available There are many locations for traditional gold mining in Indonesia. One of these is in Murung Raya District, Central Kalimantan Province. Mining activities involving the application of traditional gold processing technology have a high potential to pollute the environment, especially surface water. Therefore, this study aims to determine the impact of gold mining and processing on surface water quality around the mine site. Based on the results of field surveys and laboratory analysis, our data shows that the concentration of mercury (Hg and Cyanide (CN has reached 0.3 mg/L and 1.9 mg/L, respectively, in surface water. These values exceed the drinking water quality standards of Indonesia and WHO. Many people who live in the mining area use surface water for daily purposes including drinking, cooking, bathing and washing. This scenario is very dangerous because the effect of surface water contamination on human health cannot be immediately recognized or diagnosed. In our opinion the dissemination of knowledge regarding the treatment of gold mining wastewater is urgently required so that the quality of wastewater can be improved before it is discharged into the environment

  14. Medium-term erosion simulation of an abandoned mine site using the SIBERIA landscape evolution model

    International Nuclear Information System (INIS)

    Hancock, G.R.; Willgoose, G.R.

    2000-01-01

    This study forms part of a collaborative project designed to validate the long-term erosion predictions of the SIBERIA landform evolution model on rehabilitated mine sites. The SIBERIA catchment evolution model can simulate the evolution of landforms resulting from runoff and erosion over many years. SIBERIA needs to be calibrated before evaluating whether it correctly models the observed evolution of rehabilitated mine landforms. A field study to collect data to calibrate SIBERIA was conducted at the abandoned Scinto 6 uranium mine located in the Kakadu Region, Northern Territory, Australia. The data were used to fit parameter values to a sediment loss model and a rainfall-runoff model. The derived runoff and erosion model parameter values were used in SIBERIA to simulate 50 years of erosion by concentrated flow on the batters of the abandoned site. The SIBERIA runs correctly simulated the geomorphic development of the gullies on the man-made batters of the waste rock dump. The observed gully position, depth, volume, and morphology on the waste rock dump were quantitatively compared with the SIBERIA simulations. The close similarities between the observed and simulated gully features indicate that SIBERIA can accurately predict the rate of gully development on a man-made post-mining landscape over periods of up to 50 years. SIBERIA is an appropriate model for assessment of erosional stability of rehabilitated mine sites over time spans of around 50 years. Copyright (2000) CSIRO Australia

  15. Surface-water and groundwater interactions in an extensively mined watershed, upper Schuylkill River, Pennsylvania, USA

    Science.gov (United States)

    Cravotta,, Charles A.; Goode, Daniel J.; Bartles, Michael D.; Risser, Dennis W.; Galeone, Daniel G.

    2014-01-01

    Streams crossing underground coal mines may lose flow, while abandoned mine drainage (AMD) restores flow downstream. During 2005-12, discharge from the Pine Knot Mine Tunnel, the largest AMD source in the upper Schuylkill River Basin, had near-neutral pH and elevated concentrations of iron, manganese, and sulfate. Discharge from the tunnel responded rapidly to recharge but exhibited a prolonged recession compared to nearby streams, consistent with rapid infiltration and slow release of groundwater from the mine. Downstream of the AMD, dissolved iron was attenuated by oxidation and precipitation while dissolved CO2 degassed and pH increased. During high-flow conditions, the AMD and downstream waters exhibited decreased pH, iron, and sulfate with increased acidity that were modeled by mixing net-alkaline AMD with recharge or runoff having low ionic strength and low pH. Attenuation of dissolved iron within the river was least effective during high-flow conditions because of decreased transport time coupled with inhibitory effects of low pH on oxidation kinetics. A numerical model of groundwater flow was calibrated using groundwater levels in the Pine Knot Mine and discharge data for the Pine Knot Mine Tunnel and the West Branch Schuylkill River during a snowmelt event in January 2012. Although the calibrated model indicated substantial recharge to the mine complex took place away from streams, simulation of rapid changes in mine pool level and tunnel discharge during a high flow event in May 2012 required a source of direct recharge to the Pine Knot Mine. Such recharge produced small changes in mine pool level and rapid changes in tunnel flow rate because of extensive unsaturated storage capacity and high transmissivity within the mine complex. Thus, elimination of stream leakage could have a small effect on the annual discharge from the tunnel, but a large effect on peak discharge and associated water quality in streams.

  16. Role of mycorrhizae in forestation of surface mines

    Science.gov (United States)

    Donald H. Marx

    1980-01-01

    A brief introduction to ecto- and endomycorrhizae and their importance to plants is presented. Recent findings confirm the significance of ectomycorrhizae, particularly those formed by Pisolithus tinctorius in nurseries, to survival and growth of pine seedlings on strip-mined lands. Commercial inoculum of this fungus may be available in 1981. Recent...

  17. Mining

    Directory of Open Access Journals (Sweden)

    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.

  18. Impact of rent-seeking on productivity in Chinese coal mine safety supervision: A simulation study

    International Nuclear Information System (INIS)

    Chen, Hong; Feng, Qun; Zhu, Dandan; Han, Shuai; Long, Ruyin

    2016-01-01

    During the “golden decade” (2001–2011) of the coal industry in China, rent-seeking increased in coal mine safety supervision alongside significant improvements in coal mine safety status and increased economic benefits in the coal industry. To explore this internal relationship, we developed a Matlab simulation system and simulated the impact of rent-seeking from each level of the supervision department on coal mine productivity in different scenarios. The results showed the following. (1) Rent-seeking had no significant influence on the average level of material productivity but it had an adverse effect on the average level of mental productivity. Due to the effects of rent-seeking, productivity tended to exhibit unstable and destructive fluctuations, and rent-seeking had the dual effect of promoting and restraining productivity in a wide range with a high frequency. (2) In the supervision scenario, supervision by the high-level department was efficient, and productivity was promoted more by the national and provincial supervision department. (3) In the rent-seeking scenario, each level of the department had an intensity threshold above which coal mine accidents occurred. We also propose suggestions that focuses on the improved supervision of Chinese coal mine safety in three areas based on the “new normal” safety concept. - Highlights: •We discussed rent-seeking behavior in Chinese coal mine safety supervision. •We explored the characteristics of coal mine productivity. •We investigated the impact of rent-seeking on coal mine productivity in three scenarios. •We found rent-seeking led to great fluctuations in productivity with a dual effect. •We proposed a model strategy for Chinese coal mine safety supervision in three areas.

  19. Selected problems of the influence of underground mining on ground surface

    Energy Technology Data Exchange (ETDEWEB)

    Gren, K.; Popiolek, E.; Janusz, W.; Bartosik-Sroka, T.; Ostrowski, J.

    1980-01-01

    Problems associated with forecasting ground deformation caused by underground mining are discussed. Irregularities in surface deformations are described. Two cases of irregularities which occur in the Lower Silesian coal basin are presented. In the Nowa Ruda coal mine, irregularities accompany mining of coal seams located at a depth of about 400 m using pneumatic stowing. Mining geological conditions of working fronts are discussed. The mined coal seams are located in the protective pillar under Nowa Ruda. Zone of increased deformation is characterized by horizontal deformations 2.5 times higher than the maximum average deformation. The second case is associated with coal mining in the safety coal pillar of Nowe Miasto (a section of the town of Walbrzych). Irregularities in ground deformations occur on the rise side of mined coal seams: compression deformations are two times higher than the maximum compression beyond the zone and the three times higher than the maximum tension deformations. Ground deformations and the irregularities are shown in four diagrams. It is suggested that the described cases of deformation irregularities point out the need for individual analysis of geological and mining conditions of coal seams. (9 refs.) (In Polish)

  20. Regional scale selenium loading associated with surface coal mining, Elk Valley, British Columbia, Canada.

    Science.gov (United States)

    Wellen, Christopher C; Shatilla, Nadine J; Carey, Sean K

    2015-11-01

    Selenium (Se) concentrations in surface water downstream of surface mining operations have been reported at levels in excess of water quality guidelines for the protection of wildlife. Previous research in surface mining environments has focused on downstream water quality impacts, yet little is known about the fundamental controls on Se loading. This study investigated the relationship between mining practices, stream flows and Se concentrations using a SPAtially Referenced Regression On Watershed attributes (SPARROW) model. This work is part of a R&D program examining the influence of surface coal mining on hydrological and water quality responses in the Elk Valley, British Columbia, Canada, aimed at informing effective management responses. Results indicate that waste rock volume, a product of mining activity, accounted for roughly 80% of the Se load from the Elk Valley, while background sources accounted for roughly 13%. Wet years were characterized by more than twice the Se load of dry years. A number of variables regarding placement of waste rock within the catchments, length of buried streams, and the construction of rock drains did not significantly influence the Se load. The age of the waste rock, the proportion of waste rock surface reclaimed, and the ratio of waste rock pile side area to top area all varied inversely with the Se load from watersheds containing waste rock. These results suggest operational practices that are likely to reduce the release of Se to surface waters. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Residence time of contaminants released in surface coal mines: A wind-tunnel study

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, R.S.

    1993-08-01

    The 1990 Clean Air Act Amendments direct the U.S. Environmental Protection Agency to evaluate and modify, as required, existing dispersion models for the prediction of dispersion of dust from surface coal mines. The application of mathematical air pollution dispersion models to the dispersion of dust from surface coal mines requires knowledge of not only the amount of dust generated in the mine, but the fraction of that generated that actually escapes from the mine. The escape fraction can be related to the residence time that released material will remain, on average, within the mine. The concentration in the mine was found to follow an exponential decay function from which an exponential decay time constant (or residence time) was computed for each case. A semi-empirical formula was found that related the residence time to the mine geometry and wind direction quite well. This formula can be used to estimate escape fraction in determining the source strength for the application of mathematical dispersion models.

  2. On-Site Radon Detection of Mining-induced Fractures from Overlying Strata to the Surface: A Case Study of the Baoshan Coal Mine in China

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    2014-12-01

    Full Text Available Large-scale longwall mining of shallow coal seams may cause mining-induced fractures that can project completely through to the surface. This could lead to a series of mine safety and environmental issues, further deteriorating the already fragile ecological environment in the Western mining areas in China. Therefore, an accurate and effective understanding of the spatiotemporal evolution law of mining-induced fractures in overlying strata and its relationship to upper aquifers is critical. In this paper, the application of the geophysical-chemical properties of radon in mining engineering is explored as a potential solution to the shortcomings of existing surveying methods. A radioactive measurement method is proposed for the detection of the development of mining-induced fractures from overlying strata to the surface in the Baoshan Coal Mine (BCM. The on-site test indicated that the first weighting step is approximately 60 m, the average periodic weighting step is approximately 20 m, and the influence coverage of the advanced abutment pressure is approximately 30 m. The presented method could be used as an indirect technical support to increase the safety of coal mining by acting as a simple, fast, and reliable method of detecting mining-induced fractures in overlying strata.

  3. Evaluation of gas emission from closed mines surface to atmosphere

    OpenAIRE

    Pokryszka, Zbigniew; Tauziède, Christian

    2000-01-01

    International audience; The closed mines are likely to release into atmosphere polluting or/and dangerous gases. The detection and hazard evaluation of those emissions are a complex problem. In order to quantify and qualify these gas emissions and check gas migrations special measuring methods are required. The research done at INERIS resulted in a reliable and appropriate methodology using a flux chamber. This methodology is intended for detecting, quantifying and qualifying gas discharges, ...

  4. Simulation and optimization of evacuation routes in case of fire in underground mines

    Directory of Open Access Journals (Sweden)

    Vancho Adjiski

    2015-01-01

    Full Text Available Risks of fire occurrence in underground mines are known for a long time. Evacuation and rescue plans allow to each underground mine to respond and establish control in case of emergency. The primary goal of this paper is to determine the optimal system for evacuation in case of fire in underground mines and through a process of computer simulation to be presented to all workers that are affected by this issue. In this study is developed a system that allows by using available software to work out the complete evacuation plans that include analysis of fire scenarios and optimal routes for evacuation. With development of database of fire scenarios, it is possible to plan routes for evacuation in all situations. This presented methodology can serve to make effective system for evacuation and rescue in case of fire and to help save lives and protect the financial investment in the mine. This methodology represents the most economical option of making an effective system for evacuation and also can serve as an idea of making a software package that includes all the steps of making a system for evacuation and rescue in case of fire in underground mines. This presented model will have increased accuracy compared to other models presented so far, because of the prepared 3D model of the underground mine which includes the actual dimensions of the mine along with its associated elements from which the fire dynamics and system for evacuation depends.

  5. Ensuring the Environmental and Industrial Safety in Solid Mineral Deposit Surface Mining

    Science.gov (United States)

    Trubetskoy, Kliment; Rylnikova, Marina; Esina, Ekaterina

    2017-11-01

    The growing environmental pressure of mineral deposit surface mining and severization of industrial safety requirements dictate the necessity of refining the regulatory framework governing safe and efficient development of underground resources. The applicable regulatory documentation governing the procedure of ore open-pit wall and bench stability design for the stage of pit reaching its final boundary was issued several decades ago. Over recent decades, mining and geomechanical conditions have changed significantly in surface mining operations, numerous new software packages and computer developments have appeared, opportunities of experimental methods of source data collection and processing, grounding of the permissible parameters of open pit walls have changed dramatically, and, thus, methods of risk assessment have been perfected [10-13]. IPKON RAS, with the support of the Federal Service for Environmental Supervision, assumed the role of the initiator of the project for the development of Federal norms and regulations of industrial safety "Rules for ensuring the stability of walls and benches of open pits, open-cast mines and spoil banks", which contribute to the improvement of economic efficiency and safety of mineral deposit surface mining and enhancement of the competitiveness of Russian mines at the international level that is very important in the current situation.

  6. 77 FR 26046 - Proposed Extension of Existing Information Collection; Ground Control for Surface Coal Mines and...

    Science.gov (United States)

    2012-05-02

    ... provided in the desired format, reporting burden (time and financial resources) is minimized, collection... Extension of Existing Information Collection; Ground Control for Surface Coal Mines and Surface Work Areas... Federal agencies with an opportunity to comment on proposed and continuing collections of information in...

  7. Chapter 4: Low compaction grading to enhance reforestation success on coal surface mines

    Science.gov (United States)

    R. Sweigard; J. Burger; C. Zipper; J. Skousen; C. Barton; P. Angel

    2017-01-01

    This Forest Reclamation Advisory describes final-grading techniques for reclaiming coal surface mines to forest postmining land uses. Final grading that leaves a loose soil and a rough surface increases survival of planted seedlings and forest productivity. Such practices are often less costly than traditional "smooth grading" while meeting the requirements...

  8. Development and Application of Blast Casting Technique in Large-Scale Surface Mines: A Case Study of Heidaigou Surface Coal Mine in China

    Directory of Open Access Journals (Sweden)

    Li Ma

    2016-01-01

    Full Text Available Blast casting is a high-efficiency technique applied in surface mines for overburden removal and results in stripping cost savings. According to ballistic theory and center-of-mass frame basic movement principles, key factors influencing blast casting effect were analyzed, which include bench height and mining panel width, inclined angle of blast holes, explosive unit consumption (EUC, delay-time interval, presplitting, and blast hole pattern parameters. An intelligent design software was developed for obtaining better breaking and casting effect, and the error rates predicted with actual result can be controlled with 10%. Blast casting technique was successfully applied in Heidaigou Surface Coal Mine (HSCM with more than 34% of material casted into the inner dump. A ramp ditch was set within the middle inner dump for coal transportation. The procedure of stripping and excavating was implemented separately and alternately in the two sections around the middle ramp ditch. An unconstrained-nonlinear model was deduced for optimizing the shift distance of the middle ramp. The calculation results show that optimum shift distance of HSCM is 480 m, and the middle ditch should be shifted after 6 blast casting mining panels being stripped.

  9. Mine safety sensors: Test results in a simulated test stope

    CSIR Research Space (South Africa)

    Dickens, J

    2013-10-01

    Full Text Available of the field of view of a thermal camera for identifying the entire extent of a loose rock in a narrow mine stope. Due to the field of view limitations of even wide-angle thermal cameras it is necessary to stitch together multiple image to get a full view... that are colder due to a fracture. To do this we compute: (1) a measure of flatness within a fixed radius, and (2) the coefficient of variation of temperature (CVT) within the same neighbourhood. The Fig. 5. The un-mounted 3D-thermal scanner flatness and the CVT...

  10. Deep Impact: Effects of Mountaintop Mining on Surface Topography, Bedrock Structure, and Downstream Waters.

    Science.gov (United States)

    Ross, Matthew R V; McGlynn, Brian L; Bernhardt, Emily S

    2016-02-16

    Land use impacts are commonly quantified and compared using 2D maps, limiting the scale of their reported impacts to surface area estimates. Yet, nearly all land use involves disturbances below the land surface. Incorporating this third dimension into our estimates of land use impact is especially important when examining the impacts of mining. Mountaintop mining is the most common form of coal mining in the Central Appalachian ecoregion. Previous estimates suggest that active, reclaimed, or abandoned mountaintop mines cover ∼7% of Central Appalachia. While this is double the areal extent of development in the ecoregion (estimated to occupy impacts are far more extensive than areal estimates alone can convey as the impacts of mines extend 10s to 100s of meters below the current land surface. Here, we provide the first estimates for the total volumetric and topographic disturbance associated with mining in an 11 500 km(2) region of southern West Virginia. We find that the cutting of ridges and filling of valleys has lowered the median slope of mined landscapes in the region by nearly 10 degrees while increasing their average elevation by 3 m as a result of expansive valley filling. We estimate that in southern West Virginia, more than 6.4km(3) of bedrock has been broken apart and deposited into 1544 headwater valley fills. We used NPDES monitoring datatsets available for 91 of these valley fills to explore whether fill characteristics could explain variation in the pH or selenium concentrations reported for streams draining these fills. We found that the volume of overburden in individual valley fills correlates with stream pH and selenium concentration, and suggest that a three-dimensional assessment of mountaintop mining impacts is necessary to predict both the severity and the longevity of the resulting environmental impacts.

  11. Restoration of surface-mined lands with rainfall harvesting

    Energy Technology Data Exchange (ETDEWEB)

    Sauer, R.H.; Rickard, W.H.

    1982-12-01

    Strip mining for coal in the arid western US will remove grazing land as energy demands are met. Conventional resotration usually includes leveling the spoil banks and covering them with top soil, fertilizing, seeding and irrigation with well or river water. An overview of research on an alternate method of restoring this land is reported. From 1976 through 1981 studies were conducted on the use of water harvesting, the collection and use of rainfall runoff, to restore the vegetative productivity of strip mined lands in arid regions. These studies tested the technical and economic feasibility of using partially leveled spoil banks at strip mines as catchment areas to collect and direct runoff to the topsoiled valley floor where crops were cultivated. Information was collected on the efficiency of seven treatments to increase runoff from the catchment areas and on the productivity of seven crops. The experiments were conducted in arid areas of Washington, Arizona, and Colorado. It was concluded that water harvesting can replace or augment expensive and inadequate supplies of well and river water in arid regions with a suitable climate. These studies showed that some treatments provided adequate runoff to produce a useful crop in the valleys, thus making this alternative approach to restoration technically feasible. This approach was also potentially economically feasible where the treatment costs of the catchment areas were low, the treatment was effective, the crop was productive and valuable, and earthmoving costs were lower than with conventional restoration involving complete leveling of spoil banks. It was also concluded that water harvesting can be made more effective with further information on catchment area treatments, which crops are most adaptable to water harvesting, the optimum incline of the catchment areas and climatic influences on water harvesting.

  12. Assessment of surface and subsurface ground disturbance due to underground mining

    International Nuclear Information System (INIS)

    Khair, A.W.

    1994-01-01

    This paper presents highlights of the research carried out at West Virginia University in order to assess surface and subsurface ground disturbance due to longwall mining. Extensive instrumentation and measurements have been made over three longwall mines in northern West Virginia during a three-year period. Various monitoring techniques including full profile borehole extensometer, full profile borehole inclinometers, time domain reflectometry, sonic reflection technique, a unique mechanical grouting method, photographic and visual observations, standard surveying, and water-level measurements were utilized. The paper's emphasis is first on surface ground movement and its impact on integrity of surface ground and structures and second on type and magnitude of subsurface ground movements associated with mine geometry and geology. A subsidence prediction model based on implementation of both mechanisms of ground movement around the excavation and the geologic and geotechnical properties of the rock/coal surrounding the excavation has been developed. 8 refs., 14 figs., 1 tab

  13. Simulation of high resolution mine hunting sonar measurements

    NARCIS (Netherlands)

    Hansen, R.E.; Callow, H.J.; Saebo, T.O.; Groen, J.; Quesson, B.A.J.; Sabel, J.C.

    2005-01-01

    An acoustic simulator is vital for the development of sonar data processing. The most important features in the TNO 3D simulator SIMONA are detailed target response including shadow, reverberation modelling, sonar properties and multipath. The verification and development of SIMONA was realized

  14. Disposing of coal combustion residues in inactive surface mines: Effects on water quality

    International Nuclear Information System (INIS)

    Kim, A.G.; Ackman, T.E.

    1994-01-01

    The disposal of coal combustion residues (CCR) in surface and underground coal mines can provide a stable, low-maintenance alternative to landfills, benefiting the mining and electric power industries. The material may be able to improve water quality at acid generating abandoned or reclaimed coal mine sites. Most combustion residues are alkaline, and their addition to the subsurface environment could raise the pH, limiting the propagation of pyrite oxidizing bacteria and reducing the rate of acid generation. Many of these CCR are also pozzolanic, capable of forming cementitious grouts. Grouts injected into the buried spoil may decrease its permeability and porosity, diverting water away from the pyritic material. Both mechanisms, alkaline addition and water diversion, are capable of reducing the amount of acid produced at the disposal site. The US Bureau of Mines is cooperating in a test of subsurface injection of CCR into a reclaimed surface mine. Initially, a mixture of fly ash, lime, and acid mine drainage (AMD) sludge was injected. Lime was the source of calcium for the formation of the pozzolanic grout. Changes in water quality parameters (pH, acidity, anions, and trace metals) in water samples from wells and seeps indicate a small but significant improvement after CCR injection. Changes in the concentration of heavy metals in the water flowing across the site were apparently influenced by the presence of flyash

  15. Surface structural damage associated with longwall mining near Tuscaloosa, Alabama: a case history

    International Nuclear Information System (INIS)

    Isphording, W.C.

    1992-01-01

    Initially the paper examines the frequency of coal mine subsidence and the influence on surface subsidence of subsurface mining methods, i.e. room and pillar and longwall mining. A case study of the subsidence damage caused to a log house near Tuscaloosa, Alabama (USA), when a longwall panel passed beneath it is presented. The damage resulted in the homeowners suing the mining company for negligence. The article discusses information provided to the plaintiffs attorneys by the author. Aspects covered are: the subsidence and damage to the property; prediction of subsidence; the monitoring of subsidence; and the prevention of subsidence. An out-of-court settlement was agreed by the two parties. 15 refs., 5 figs

  16. Fifth symposium on surface mining and reclamation. NCA/BCR coal conference and Expo IV

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-01-01

    The Fifth Symposium on Surface Mining and Reclamation, sponsored by the National Coal Association and Bituminous Coal Research, Inc., was held at the Kentucky Fair and Exposition Center, Louisville, Kentucky, October 18-20, 1977. Twenty-six papers from the proceedings have been entered individually into EDB and ERA. Topics covered include spoil bank revegetation, use of aerial photography, reclamation for row crop production, hydrology, computer programs related to this work, subirrigated alluvial valley floors, reclamation on steep slopes, mountain top removal, surface mine road design, successional processes involved in reclamation, land use planning, etc. (LTN)

  17. Autumn olive (Elaeagnus umbellata) presence and proliferation on former surface coal mines in Eastern USA

    Science.gov (United States)

    Oliphant, Adam J.; Wynne, R.H.; Zipper, Carl E.; Ford, W. Mark; Donovan, P. F.; Li, Jing

    2017-01-01

    Invasive plants threaten native plant communities. Surface coal mines in the Appalachian Mountains are among the most disturbed landscapes in North America, but information about land cover characteristics of Appalachian mined lands is lacking. The invasive shrub autumn olive (Elaeagnus umbellata) occurs on these sites and interferes with ecosystem recovery by outcompeting native trees, thus inhibiting re-establishment of the native woody-plant community. We analyzed Landsat 8 satellite imagery to describe autumn olive’s distribution on post-mined lands in southwestern Virginia within the Appalachian coalfield. Eight images from April 2013 through January 2015 served as input data. Calibration and validation data obtained from high-resolution aerial imagery were used to develop a land cover classification model that identified areas where autumn olive was a primary component of land cover. Results indicate that autumn olive cover was sufficiently dense to enable detection on approximately 12.6 % of post-mined lands within the study area. The classified map had user’s and producer’s accuracies of 85.3 and 78.6 %, respectively, for the autumn olive coverage class. Overall accuracy was assessed in reference to an independent validation dataset at 96.8 %. Autumn olive was detected more frequently on mines disturbed prior to 2003, the last year of known plantings, than on lands disturbed by more recent mining. These results indicate that autumn olive growing on reclaimed coal mines in Virginia and elsewhere in eastern USA can be mapped using Landsat 8 Operational Land Imager imagery; and that autumn olive occurrence is a significant landscape vegetation feature on former surface coal mines in the southwestern Virginia segment of the Appalachian coalfield.

  18. Utilization of InSAR differential interferometry for surface deformation detection caused by mining

    Energy Technology Data Exchange (ETDEWEB)

    Yang, F. [Liaoning Technical Univ., Fuxin (China). School of Geomatics; Shao, Y. [Liaoning Technical Univ., Fuxin (China). Dept. of Foreign Language; Guichen, M. [Gifu Univ., Yanagido, Gifu (Japan). Dept. of Civil Engineering

    2010-07-01

    In China, the surface deformation of ground has been a significant geotechnical problem as a result of cracks in the ground surface, collapsing of house, and subsidence of roads. A powerful technology for detecting surface deformation in the ground is differential interferometry using synthetic aperture radar (INSAR). The technology enables the analysis from different phase of micro-wave between two observed data by synthetic aperture radar (SAR) of surface deformation of ground such as ground subsidence, land slide, and slope failure. In January 2006, the advanced land observing satellite was launched by the Japan Aerospace Exploration Agency. This paper presented an analytical investigation to detect ground subsidence or change caused by mining, overuse of ground water, and disaster. Specifically, the paper discussed the INSAR monitoring technology of the mine slope, including INSAR data sources and processing software; the principle of synthetic aperture radar interferometry; principles of differential SAR interferometry; and INSAR technology to slope monitoring of the Haizhou open pit mine. The paper also discussed the Haizhou strip mine side slope INSAR monitoring results and tests. It was concluded that the use of synthetic aperture radar interferometer technique was the optimal technique to provide three-dimensional spatial information and minimal change from ground surface by spatial remote sensing device. 18 refs., 5 figs.

  19. Simulation of windblown dust transport from a mine tailings impoundment using a computational fluid dynamics model

    Science.gov (United States)

    Stovern, Michael; Felix, Omar; Csavina, Janae; Rine, Kyle P.; Russell, MacKenzie R.; Jones, Robert M.; King, Matt; Betterton, Eric A.; Sáez, A. Eduardo

    2014-09-01

    Mining operations are potential sources of airborne particulate metal and metalloid contaminants through both direct smelter emissions and wind erosion of mine tailings. The warmer, drier conditions predicted for the Southwestern US by climate models may make contaminated atmospheric dust and aerosols increasingly important, due to potential deleterious effects on human health and ecology. Dust emissions and dispersion of dust and aerosol from the Iron King Mine tailings in Dewey-Humboldt, Arizona, a Superfund site, are currently being investigated through in situ field measurements and computational fluid dynamics modeling. These tailings are heavily contaminated with lead and arsenic. Using a computational fluid dynamics model, we model dust transport from the mine tailings to the surrounding region. The model includes gaseous plume dispersion to simulate the transport of the fine aerosols, while individual particle transport is used to track the trajectories of larger particles and to monitor their deposition locations. In order to improve the accuracy of the dust transport simulations, both regional topographical features and local weather patterns have been incorporated into the model simulations. Results show that local topography and wind velocity profiles are the major factors that control deposition.

  20. In vitro studies evaluating leaching of mercury from mine waste calcine using simulated human body fluids

    Science.gov (United States)

    Gray, John E.; Plumlee, Geoffrey S.; Morman, Suzette A.; Higueras, Pablo L.; Crock, James G.; Lowers, Heather A.; Witten, Mark L.

    2010-01-01

    In vitro bioaccessibility (IVBA) studies were carried out on samples of mercury (Hg) mine-waste calcine (roasted Hg ore) by leaching with simulated human body fluids. The objective was to estimate potential human exposure to Hg due to inhalation of airborne calcine particulates and hand-to-mouth ingestion of Hg-bearing calcines. Mine waste calcines collected from Hg mines at Almadén, Spain, and Terlingua, Texas, contain Hg sulfide, elemental Hg, and soluble Hg compounds, which constitute primary ore or compounds formed during Hg retorting. Elevated leachate Hg concentrations were found during calcine leaching using a simulated gastric fluid (as much as 6200 μg of Hg leached/g sample). Elevated Hg concentrations were also found in calcine leachates using a simulated lung fluid (as much as 9200 μg of Hg leached/g), serum-based fluid (as much as 1600 μg of Hg leached/g), and water of pH 5 (as much as 880 μg of Hg leached/g). The leaching capacity of Hg is controlled by calcine mineralogy; thus, calcines containing soluble Hg compounds contain higher leachate Hg concentrations. Results indicate that ingestion or inhalation of Hg mine-waste calcine may lead to increased Hg concentrations in the human body, especially through the ingestion pathway.

  1. New simulated gas detector offers realistic training for mine rescue teams

    Energy Technology Data Exchange (ETDEWEB)

    Bealko, S.B.; Alexander, D.; Chasko, L.L. [National Inst. for Occupational Safety and Health, Pittsburgh, PA (United States). Office of Mine Safety and Health Research; Holtan, J. [LightsOn Safety Solutions, Spring, TX (United States)

    2010-07-01

    The National Institute for Occupational Safety and Health, together with LightsOn Safety Solutions, evaluated 2 versions of a multi-gas simulated gas monitor system (GMS) in separate field trials with mine rescue teams. This paper described the GMS wireless simulation tool along with its development and testing. It also described the GMS functions for the initial phase of testing as well as plans for the next phase of research which may introduce tracking and automation features. The GMS requires a personal computer and uses a wireless local area network. The GMS teaches mine rescue members about gas detection and helps them understand the importance of gas concentrations. In addition, it promotes decision-making actions by team members and offers a more realistic method of receiving gas concentration readings using a simulated hand-held gas detector. The purpose of the evaluation was to determine if the electronic placard in the GMS could be used by mine rescue teams instead of the currently used cardboard placards, and if the functionality of the device was suitable, reliable and practical. Results from the second field trial demonstrated improvements with the GMS over the original prototype technology, particularly with regards to wireless and connectivity issues. The GMS was successfully incorporated into the mine rescue exercises as planned, with very few problems encountered. 4 refs., 2 figs.

  2. Numerical simulation of electromagnetic surface treatment

    Science.gov (United States)

    Sonde, Emmanuel; Chaise, Thibaut; Nelias, Daniel; Robin, Vincent

    2018-01-01

    Surface treatment methods, such as shot peening or laser shock peening, are generally used to introduce superficial compressive residual stresses in mechanical parts. These processes are carried out during the manufacturing steps or for the purpose of repairing. The compressive residual stresses prevent the initiation and growth of cracks and thus improve the fatigue life of mechanical components. Electromagnetic pulse peening (EMP) is an innovative process that could be used to introduce compressive residual stresses in conductive materials. It acts by generating a high transient electromagnetic field near the working surface. In this paper, the EMP process is presented and a sequentially coupled electromagnetic and mechanical model is developed for its simulation. This 2D axisymmetric model is set up with the commercial finite element software SYSWELD. After description and validation, the numerical model is used to simulate a case of introducing residual stresses of compression in a nickel-based alloy 690 thick sample, by the means of electromagnetic pulses. The results are presented in terms of effective plastic strain and residual mean stress. The influence of the process parameters, such as current intensity and frequency, on the results is analyzed. Finally, the predictability of the process is shown by several correlation studies.

  3. Utilising Monte Carlo Simulation for the Valuation of Mining Concessions

    Directory of Open Access Journals (Sweden)

    Rosli Said

    2005-12-01

    Full Text Available Valuation involves the analyses of various input data to produce an estimated value. Since each input is itself often an estimate, there is an element of uncertainty in the input. This leads to uncertainty in the resultant output value. It is argued that a valuation must also convey information on the uncertainty, so as to be more meaningful and informative to the user. The Monte Carlo simulation technique can generate the information on uncertainty and is therefore potentially useful to valuation. This paper reports on the investigation that has been conducted to apply Monte Carlo simulation technique in mineral valuation, more specifically, in the valuation of a quarry concession.

  4. Seismic scanning tunneling macroscope - Elastic simulations and Arizona mine test

    KAUST Repository

    Hanafy, Sherif M.

    2012-01-01

    Elastic seismic simulations and field data tests are used to validate the theory of a seismic scanning tunneling macroscope (SSTM). For nearfield elastic simulation, the SSTM results show superresolution to be better than λ/8 if the only scattered data are used as input data. If the direct P and S waves are muted then the resolution of the scatterer locations are within about λ/5. Seismic data collected in an Arizona tunnel showed a superresolution limit of at least λ/19. These test results are consistent with the theory of the SSTM and suggest that the SSTM can be a tool used by geophysicists as a probe for near-field scatterers.

  5. Physical simulation and theoretical evolution for ground fissures triggered by underground coal mining.

    Science.gov (United States)

    Yang, Jing-Hu; Yu, Xiang; Yang, Yi; Yang, Zeng-Qiang

    2018-01-01

    Underground coal mining activities are prone to cause movement and breakage in geological strata and also lead to mining subsidence and even ground fissures. Along the direction working panel advancing, ground fissures may occur in roof in front and/or behind working panel. However, the investigations of previous similarity tests in lab only emphasize on the region behind working panel. By improving strata material property in construction and mounting artificial pressure devices, two physical simulation tests were conducted and successfully investigated the simulated results. Then, the mechanical model of "cantilever beam and elastic foundation beam" was proposed to calculate the stress distribution and the crack initiation angle in overlying strata and it well explains the mechanisms of ground fissures generation and propagation. Results show that, the maximum internal force in roof always occurred in front of working panel. However, because the void space in gob due to excavation is large enough to cause the bend and rotation of roof strata, compare to the triaxially compressed region in front of working panel, the roof always broke off at some positions above gob since the stress concentration resulting from such bend and rotation of strata could easily reach the limit strength of strata rocks. Also, the length of cantilever beam changed dynamically as respect to the panel advancing and the breakage intervals. Thus, the breakage position where the internal force first reached the limit tensile strength is not fixed and there will be two different kinds of relative positions between the crack initiation point and the working panel. The crack initiation direction is always perpendicular to the internal force, and the crack propagation direction is affected by the initiation angle, overburden-separation degree and the position of the hydraulic shields. If there is no overburden-separation or less, the roofs will break off as a composite beam and the propagation

  6. Physical simulation and theoretical evolution for ground fissures triggered by underground coal mining

    Science.gov (United States)

    Yu, Xiang; Yang, Yi; Yang, Zeng-Qiang

    2018-01-01

    Underground coal mining activities are prone to cause movement and breakage in geological strata and also lead to mining subsidence and even ground fissures. Along the direction working panel advancing, ground fissures may occur in roof in front and/or behind working panel. However, the investigations of previous similarity tests in lab only emphasize on the region behind working panel. By improving strata material property in construction and mounting artificial pressure devices, two physical simulation tests were conducted and successfully investigated the simulated results. Then, the mechanical model of “cantilever beam and elastic foundation beam” was proposed to calculate the stress distribution and the crack initiation angle in overlying strata and it well explains the mechanisms of ground fissures generation and propagation. Results show that, the maximum internal force in roof always occurred in front of working panel. However, because the void space in gob due to excavation is large enough to cause the bend and rotation of roof strata, compare to the triaxially compressed region in front of working panel, the roof always broke off at some positions above gob since the stress concentration resulting from such bend and rotation of strata could easily reach the limit strength of strata rocks. Also, the length of cantilever beam changed dynamically as respect to the panel advancing and the breakage intervals. Thus, the breakage position where the internal force first reached the limit tensile strength is not fixed and there will be two different kinds of relative positions between the crack initiation point and the working panel. The crack initiation direction is always perpendicular to the internal force, and the crack propagation direction is affected by the initiation angle, overburden-separation degree and the position of the hydraulic shields. If there is no overburden-separation or less, the roofs will break off as a composite beam and the

  7. Computer simulation of surface and film processes

    Science.gov (United States)

    Tiller, W. A.; Halicioglu, M. T.

    1984-01-01

    All the investigations which were performed employed in one way or another a computer simulation technique based on atomistic level considerations. In general, three types of simulation methods were used for modeling systems with discrete particles that interact via well defined potential functions: molecular dynamics (a general method for solving the classical equations of motion of a model system); Monte Carlo (the use of Markov chain ensemble averaging technique to model equilibrium properties of a system); and molecular statics (provides properties of a system at T = 0 K). The effects of three-body forces on the vibrational frequencies of triatomic cluster were investigated. The multilayer relaxation phenomena for low index planes of an fcc crystal was analyzed also as a function of the three-body interactions. Various surface properties for Si and SiC system were calculated. Results obtained from static simulation calculations for slip formation were presented. The more elaborate molecular dynamics calculations on the propagation of cracks in two-dimensional systems were outlined.

  8. 30 CFR 761.15 - Procedures for waiving the prohibition on surface coal mining operations within the buffer zone...

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Procedures for waiving the prohibition on surface coal mining operations within the buffer zone of an occupied dwelling. 761.15 Section 761.15... surface coal mining operations within the buffer zone of an occupied dwelling. (a) This section does not...

  9. 77 FR 62266 - Proposed Extension of Existing Information Collection; Daily Inspection of Surface Coal Mines...

    Science.gov (United States)

    2012-10-12

    ... collections of information in accordance with the Paperwork Reduction Act of 1995. This program helps to assure that requested data can be provided in the desired format, reporting burden (time and financial... Extension of Existing Information Collection; Daily Inspection of Surface Coal Mines; Certified Person...

  10. Baseline studies and evaluation of effects of surface discharge of deep-sea mining - INDEX area

    Digital Repository Service at National Institute of Oceanography (India)

    DeSousa, S.N.; Sardessai, S.

    . An evaluation of possible effects of surface discharge of mining fines - a slurry consisting of fine nodule fragments, bottom water and sediments - suggests that the discharge, with an expected solid content of 50 g/l, will induce increased primary production...

  11. Reforestation species study on a reclaimed surface mine in western Maryland

    Science.gov (United States)

    Jay A. Engle

    1980-01-01

    Westvaco Forest Research established a species comparison test including eighteen species of trees in the spring of 1978 on a recently reclaimed surface mine in Garrett County, Maryland. After two growing seasons height growth of all species has not been impressive. Seven species have better than 75 percent survival with pitch pine being best. Seven other species have...

  12. Reforestation Efforts in Indiana Following the Surface Mining Control and Reclamation Act of 1977

    Science.gov (United States)

    Stephen D. Fillmore; John W. Groninger

    2004-01-01

    During the summer of 2002, data were collected from 22 post-Surface Mining Control and Reclamation Act sites in southwestern Indiana. Tree growth across these sites was generally poor, with site index values typically less than 40 feet (base age 50) for upland oaks. Robinina pseudoacacia (black locust) was observed to be the primary overstory tree...

  13. The design procedures on brick building against surface ground deformations due to mining and earthquake

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, J.; Yang, S. (China University of Mining and Technology (China))

    1992-05-01

    By analysing the effects of ground motion and deformation on surface buildings, and drawing on the experience of damages caused by the Tangshan and Chenhai earthquakes, the authors discuss the design of brick and concrete buildings which are protected against the damaging effects of both earthquakes and mining activities. 5 figs.

  14. Blasting injuries in surface mining with emphasis on flyrock and blast area security

    Energy Technology Data Exchange (ETDEWEB)

    Bajpayee, T.S.; Rehak, T.R.; Mowrey, G.L.; Ingram, D.K. [NIOSH, Pittsburgh, PA (USA). Pittsburgh Research Lab.

    2004-07-01

    Blasting is a hazardous component of surface mining. Serious injuries and fatalities result from improper judgment or practice during rock blasting. This paper describes several fatal injury case studies, analyzes causative factors, and emphasizes preventive measures. During the 21-year period from 1978 to 1998, the mean yearly explosive-related injuries (fatal and nonfatal) for surface coal mines was 8.86 (95% CI: 6.38-11.33), and for surface metal/nonmetal mines 10.76 (95% CI: 8.39-13.14). Flyrock and lack of blast area security accounted for 68.2% of these injuries. Case studies indicate that the causative factors for fatal injuries are primarily personal and task-related and to some extent environmental. A reduction in the annual injuries in surface coal mines was observed during the 10-year period of 1989-1998 (5.80 (95% CI: 2.71-8.89)) compared to the previous 10-year period of 1979-1988 (10.90 (95% CI: 7.77-14.14)). However, such reduction was not noticed in the metal/nometal sector (i.e., 9.30 (95% CI: 6.84-11.76) for the period 1989-1998 compared with 11.00 (95% CI: 7.11-14.89) for the period 1979-1988). Discussion of case studies during safety meetings will help to mitigate fatal injuries and derive important payoffs in terms of lower risks and costs of injuries.

  15. Modeling forest ecosystem changes resulting from surface coal mining in West Virginia

    Science.gov (United States)

    John Brown; Andrew J. Lister; Mary Ann Fajvan; Bonnie Ruefenacht; Christine Mazzarella

    2012-01-01

    The objective of this project is to assess the effects of surface coal mining on forest ecosystem disturbance and restoration in the Coal River Subbasin in southern West Virginia. Our approach is to develop disturbance impact models for this subbasin that will serve as a case study for testing the feasibility of integrating currently available GIS data layers, remote...

  16. Selective bibliography of surface coal mining and reclamation literature. Volume 2. Interior Coal Province

    Energy Technology Data Exchange (ETDEWEB)

    Patricoski, M. L.; Daniels, L. K.; Sobek, A. A.

    1979-08-01

    This bibliography has been compiled for use by researchers, students, and other groups who need a reference source of published literature related to surface coal mining and reclamation in the Interior Coal Province. This bibliography contains more than 1300 references, including government reports, journal articles, symposium proceedings, industrial reports, workshop proceedings, theses, and bibliographies. A simple format was used to categorize citations.

  17. Characteristics of hazardous airborne dust around an Indian surface coal mining area.

    Science.gov (United States)

    Ghose, Mrinal K; Majee, S R

    2007-07-01

    Surface coal mining creates more air pollution problems with respect to dust than underground mining . An investigation was conducted to evaluate the characteristics of the airborne dust created by surface coal mining in the Jharia Coalfield. Work zone air quality monitoring was conducted at six locations, and ambient air quality monitoring was conducted at five locations, for a period of 1 year. Total suspended particulate matter (TSP) concentration was found to be as high as 3,723 microg/m(3), respirable particulate matter (PM10) 780 microg/m(3), and benzene soluble matter was up to 32% in TSP in work zone air. In ambient air, the average maximum level of TSP was 837 microg/m(3), PM10 170 microg/m(3) and benzene soluble matter was up to 30%. Particle size analysis of TSP revealed that they were more respirable in nature and the median diameter was around 20 microm. Work zone air was found to have higher levels of TSP, PM10 and benzene soluble materials than ambient air. Variations in weight percentages for different size particles are discussed on the basis of mining activities. Anionic concentration in TSP was also determined. This paper concludes that more stringent air quality standards should be adopted for coal mining areas and due consideration should be given on particle size distribution of the air-borne dust while designing control equipment.

  18. Conformational dynamics of ATP/Mg:ATP in motor proteins via data mining and molecular simulation

    Science.gov (United States)

    Bojovschi, A.; Liu, Ming S.; Sadus, Richard J.

    2012-08-01

    The conformational diversity of ATP/Mg:ATP in motor proteins was investigated using molecular dynamics and data mining. Adenosine triphosphate (ATP) conformations were found to be constrained mostly by inter cavity motifs in the motor proteins. It is demonstrated that ATP favors extended conformations in the tight pockets of motor proteins such as F1-ATPase and actin whereas compact structures are favored in motor proteins such as RNA polymerase and DNA helicase. The incorporation of Mg2+ leads to increased flexibility of ATP molecules. The differences in the conformational dynamics of ATP/Mg:ATP in various motor proteins was quantified by the radius of gyration. The relationship between the simulation results and those obtained by data mining of motor proteins available in the protein data bank is analyzed. The data mining analysis of motor proteins supports the conformational diversity of the phosphate group of ATP obtained computationally.

  19. Nuclear waste repository simulation experiments. Asse salt mine: Annual report 1984

    International Nuclear Information System (INIS)

    Rothfuchs, T.; Feddersen, H.K.; Schwarzianeck, P.; Staupendahl, G.; Coyle, A.J.; Kalia, H.; Eckert, J.

    1985-01-01

    This is the Second Annual Report (1984) which describes experiments simulating a nuclear waste repository at the 800 meter-level of the Asse Salt Mine in the Federal Republic of Germany. The report describes the Asse Salt Mine, the test equipment, and the pretest properties of the salt in the mine and in the vicinity of the test area. Also included are test data for the first sixteen months of operation on the following: brine migration rates, thermal mechanical behavior of the salt (including room closure, stress readings and thermal profiles) and borehole gas pressures. In addition to field data laboratory analyses of results are also included in this report. The duration of the experiment will be two years, ending in December 1985. (orig.)

  20. Nuclear waste repository simulation experiments, Asse salt mine, Federal Republic of Germany. Annual report 1984

    International Nuclear Information System (INIS)

    Rothfuchs, T.; Feddersen, H.K.; Schwarzianeck, P.; Staupendahl, G.; Coyle, A.J.; Eckert, J.; Kalia, H.

    1986-07-01

    This is the second joint annual report (1984) on experiments simulating a nuclear waste repository at the 800-m (2624-ft) level of the Asse salt mine in the Federal Republic of Germany. This report describes the Asse salt mine, the test equipment, and the pretest properties of the salt in the mine and in the vicinity of the test area. Also included are test data for the first 19 months of operation on the following: brine migration rates, thermal mechanical behavior of the salt (including room closure, stress reading, and thermal profiles), and borehole gas pressures. In addition to field data, laboratory analyses of results are included in this report. The duration of the experiment will be 2 years, ending in December 1985

  1. Numerical Simulation of Flow and Pollution Dispersion in the Area of Opencast Coal Mine

    Science.gov (United States)

    Bodnár, T.; Beneš, L.; Kozel, K.

    2008-09-01

    This paper presents some of the results of numerical simulation of flow and pollution dispersion in the proximity of coal deposit placed in the area of opencast coal mine. The mathematical model is based on Reynolds averaged Navier-Stokes equations for incompressible flows. Turbulent closure of the model is obtained by simple algebraic turbulence model. The numerical solution is carried out by the semi-implicit finite-difference scheme. The 3D results are presented for the flow in real terrain including simulated obstacles. Model sensitivity is studied with respect to simulated obstacle size and shape.

  2. Numerical simulation of roadway support in a sandstone-type uranium mine

    International Nuclear Information System (INIS)

    Liu Huipeng; Li Yu; Song Lixia

    2009-01-01

    At present, the most surrounding rocks of sandstone-type uranium mines in China are mudstone, sandstone, pelitic siltstone, and so on. They show the characteristics of soft rock. Such uranium deposit is not fit for in-situ leaching. If the uranium ores are mined by conventional mining method, one of the problems to be solved is the support technique in the soft rock roadway. So, taking a uranium mine in Inner Mongolia as the research object, the support technique in the soft rock roadway of the sandstone-type uranium deposits is studied. Through on-site engineering geological investigation and laboratory test, the main reasons for roadway damage are analyzed. A technique of support in the soft rock roadway of sandstone-type uranium deposits is put forward by drawing on the expericnce of soft rock roadway support in coal mines. The roadway shape and support parameters are optimized by using a numerical simulation method. The results verified the feasibility of the supporting technique. (authors)

  3. Contamination in surface waters around uranium mines in the Guadiana Basin

    Energy Technology Data Exchange (ETDEWEB)

    Bejarano, J.D.; Tome, F.V.; Sanchez, A.M.; Sanchez, A.R.

    1988-01-01

    In a study of the contamination by uranium mines in the River Guadiana basin, we have found the natural higher concentration of uranium in samples collected near the mines and the expected decrease with distance in samples farther away. In spite of this expected result, there is another interesting fact: a natural isotopic separation is observed. Measurements were by alpha spectrometry with a silicon surface barrier detector. The study was completed with total gamma activity at the same sites as for alphas, using an Nal(Tl) detector. (author).

  4. Three-Dimensional Computer Simulation as an Important Competence Based Aspect of a Modern Mining Professional

    Science.gov (United States)

    Aksenova, Olesya; Pachkina, Anna

    2017-11-01

    The article deals with the problem of necessity of educational process transformation to meet the requirements of modern miming industry; cooperative developing of new educational programs and implementation of educational process taking into account modern manufacturability. The paper proves the idea of introduction into mining professionals learning process studying of three-dimensional models of surface technological complex, ore reserves and underground digging complex as well as creating these models in different graphic editors and working with the information analysis model obtained on the basis of these three-dimensional models. The technological process of manless coal mining at the premises of the mine Polysaevskaya controlled by the information analysis models built on the basis of three-dimensional models of individual objects and technological process as a whole, and at the same time requiring the staff able to use the programs of three-dimensional positioning in the miners and equipment global frame of reference is covered.

  5. Three-Dimensional Computer Simulation as an Important Competence Based Aspect of a Modern Mining Professional

    Directory of Open Access Journals (Sweden)

    Aksenova Olesya

    2017-01-01

    Full Text Available The article deals with the problem of necessity of educational process transformation to meet the requirements of modern miming industry; cooperative developing of new educational programs and implementation of educational process taking into account modern manufacturability. The paper proves the idea of introduction into mining professionals learning process studying of three-dimensional models of surface technological complex, ore reserves and underground digging complex as well as creating these models in different graphic editors and working with the information analysis model obtained on the basis of these three-dimensional models. The technological process of manless coal mining at the premises of the mine Polysaevskaya controlled by the information analysis models built on the basis of three-dimensional models of individual objects and technological process as a whole, and at the same time requiring the staff able to use the programs of three-dimensional positioning in the miners and equipment global frame of reference is covered.

  6. Computer simulation, nuclear techniques and surface analysis

    Directory of Open Access Journals (Sweden)

    Reis, A. D.

    2010-02-01

    Full Text Available This article is about computer simulation and surface analysis by nuclear techniques, which are non-destructive. The “energy method of analysis” for nuclear reactions is used. Energy spectra are computer simulated and compared with experimental data, giving target composition and concentration profile information. Details of prediction stages are given for thick flat target yields. Predictions are made for non-flat targets having asymmetric triangular surface contours. The method is successfully applied to depth profiling of 12C and 18O nuclei in thick targets, by deuteron (d,p and proton (p,α induced reactions, respectively.

    Este artículo trata de simulación por ordenador y del análisis de superficies mediante técnicas nucleares, que son no destructivas. Se usa el “método de análisis en energía” para reacciones nucleares. Se simulan en ordenador espectros en energía que se comparan con datos experimentales, de lo que resulta la obtención de información sobre la composición y los perfiles de concentración de la muestra. Se dan detalles de las etapas de las predicciones de espectros para muestras espesas y planas. Se hacen predicciones para muestras no planas que tienen contornos superficiales triangulares asimétricos. Este método se aplica con éxito en el cálculo de perfiles en profundidad de núcleos de 12C y de 18O en muestras espesas a través de reacciones (d,p y (p,α inducidas por deuterones y protones, respectivamente.

  7. Combining a Spatial Model and Demand Forecasts to Map Future Surface Coal Mining in Appalachia.

    Science.gov (United States)

    Strager, Michael P; Strager, Jacquelyn M; Evans, Jeffrey S; Dunscomb, Judy K; Kreps, Brad J; Maxwell, Aaron E

    2015-01-01

    Predicting the locations of future surface coal mining in Appalachia is challenging for a number of reasons. Economic and regulatory factors impact the coal mining industry and forecasts of future coal production do not specifically predict changes in location of future coal production. With the potential environmental impacts from surface coal mining, prediction of the location of future activity would be valuable to decision makers. The goal of this study was to provide a method for predicting future surface coal mining extents under changing economic and regulatory forecasts through the year 2035. This was accomplished by integrating a spatial model with production demand forecasts to predict (1 km2) gridded cell size land cover change. Combining these two inputs was possible with a ratio which linked coal extraction quantities to a unit area extent. The result was a spatial distribution of probabilities allocated over forecasted demand for the Appalachian region including northern, central, southern, and eastern Illinois coal regions. The results can be used to better plan for land use alterations and potential cumulative impacts.

  8. Combining a Spatial Model and Demand Forecasts to Map Future Surface Coal Mining in Appalachia.

    Directory of Open Access Journals (Sweden)

    Michael P Strager

    Full Text Available Predicting the locations of future surface coal mining in Appalachia is challenging for a number of reasons. Economic and regulatory factors impact the coal mining industry and forecasts of future coal production do not specifically predict changes in location of future coal production. With the potential environmental impacts from surface coal mining, prediction of the location of future activity would be valuable to decision makers. The goal of this study was to provide a method for predicting future surface coal mining extents under changing economic and regulatory forecasts through the year 2035. This was accomplished by integrating a spatial model with production demand forecasts to predict (1 km2 gridded cell size land cover change. Combining these two inputs was possible with a ratio which linked coal extraction quantities to a unit area extent. The result was a spatial distribution of probabilities allocated over forecasted demand for the Appalachian region including northern, central, southern, and eastern Illinois coal regions. The results can be used to better plan for land use alterations and potential cumulative impacts.

  9. Memorandum of Understanding on Surface Coal Mining Operations Resulting in Placement of Excess Spoil Fills in the Waters of the United States

    Science.gov (United States)

    MOU on Surface Coal Mining Operations establishes a process for improving coordination in the review of permit applications required for surface coal mining and reclamation in waters of the United States

  10. Coal and Open-pit surface mining impacts on American Lands (COAL)

    Science.gov (United States)

    Brown, T. A.; McGibbney, L. J.

    2017-12-01

    Mining is known to cause environmental degradation, but software tools to identify its impacts are lacking. However, remote sensing, spectral reflectance, and geographic data are readily available, and high-performance cloud computing resources exist for scientific research. Coal and Open-pit surface mining impacts on American Lands (COAL) provides a suite of algorithms and documentation to leverage these data and resources to identify evidence of mining and correlate it with environmental impacts over time.COAL was originally developed as a 2016 - 2017 senior capstone collaboration between scientists at the NASA Jet Propulsion Laboratory (JPL) and computer science students at Oregon State University (OSU). The COAL team implemented a free and open-source software library called "pycoal" in the Python programming language which facilitated a case study of the effects of coal mining on water resources. Evidence of acid mine drainage associated with an open-pit coal mine in New Mexico was derived by correlating imaging spectrometer data from the JPL Airborne Visible/InfraRed Imaging Spectrometer - Next Generation (AVIRIS-NG), spectral reflectance data published by the USGS Spectroscopy Laboratory in the USGS Digital Spectral Library 06, and GIS hydrography data published by the USGS National Geospatial Program in The National Map. This case study indicated that the spectral and geospatial algorithms developed by COAL can be used successfully to analyze the environmental impacts of mining activities.Continued development of COAL has been promoted by a Startup allocation award of high-performance computing resources from the Extreme Science and Engineering Discovery Environment (XSEDE). These resources allow the team to undertake further benchmarking, evaluation, and experimentation using multiple XSEDE resources. The opportunity to use computational infrastructure of this caliber will further enable the development of a science gateway to continue foundational COAL

  11. Weathering behavior of mine tailings and waste rock: A surface investigation

    International Nuclear Information System (INIS)

    Domvile, S.J.; Li, M.G.; Sollner, D.D.; Nesbitt, W.

    1994-01-01

    A study focusing on the ion movement in the near surface of sulfide minerals was conducted to better understand the weathering mechanisms of mine waste materials. Tailings and waste rock samples from Canadian mines were subjected to controlled weathering studies using various chemical leachants. Leachates were analyzed for various parameters, and petrographic analyses were conducted on the solid residues. Laboratory oxidation studies of pure pyrrhotite and arsenopyrite were carried out using the surface techniques X-ray photoelectron spectroscopy (XPS) and auger electron spectroscopy (AES). The data derived from the weathering study and the surface techniques were correlated to determine mechanisms of oxidation. Several results were observed during the project: ferric iron constitutes one third of the iron present in pyrrhotite, sulfide oxidation is initiated when rock is blasted, sulfide sulfur is oxidized to di- and poly-sulfides prior to forming sulfates, and significantly more sulfate is produced upon exposure to aqueous environments than to air alone

  12. Preferential flow characteristics of reclaimed mine soils in a surface coal mine dump.

    Science.gov (United States)

    Gang, Lv; Jun, Li; Yexin, Li; Ting, Wang; Yazhuo, Liu; Xinyang, Fu

    2017-06-01

    % of the total soil profile (0∼60 cm). Moreover, a Pearson correlation was used to analyze the relationship between environmental factors (soil, water, and plant factors) and the dye coverage ratio. The dye coverage ratio of soil preferential flow under different reclamation vegetations was very significantly or significantly positively correlated with the gravel content, mean radius of soil macropores, soil saturated hydraulic conductivity, root weight density, and root length density, which promoted the formation and development of soil preferential flow. This study will provide a scientific basis for understanding the formation mechanism and perfecting the research system of soil preferential flow, vegetation restoration, and reconstruction in a dump; furthermore, this research offers significance guidance in the construction of green mines and the development of regional economics.

  13. Simulating the hydrologic cycle in coal mining subsidence areas with a distributed hydrologic model

    OpenAIRE

    Jianhua Wang; Chuiyu Lu; Qingyan Sun; Weihua Xiao; Guoliang Cao; Hui Li; Lingjia Yan; Bo Zhang

    2017-01-01

    Large-scale ground subsidence caused by coal mining and subsequent water-filling leads to serious environmental problems and economic losses, especially in plains with a high phreatic water level. Clarifying the hydrologic cycle in subsidence areas has important practical value for environmental remediation, and provides a scientific basis for water resource development and utilisation of the subsidence areas. Here we present a simulation approach to describe interactions between subsidence a...

  14. Computational Fluid Dynamics Simulation of Oxygen Seepage in Coal Mine Goaf with Gas Drainage

    Directory of Open Access Journals (Sweden)

    Guo-Qing Shi

    2015-01-01

    Full Text Available Mine fires mainly arise from spontaneous combustion of coal seams and are a global issue that has attracted increasing public attention. Particularly in china, the closure of coal workfaces because of spontaneous combustion has contributed to substantial economic loss. To reduce the occurrence of mine fires, the spontaneous coal combustion underground needs to be studied. In this paper, a computational fluid dynamics (CFD model was developed for coal spontaneous combustion under goaf gas drainage conditions. The CFD model was used to simulate the distribution of oxygen in the goaf at the workface in a fully mechanized cave mine. The goaf was treated as an anisotropic medium, and the effects of methane drainage and oxygen consumption on spontaneous combustion were considered. The simulation results matched observational data from a field study, which indicates CFD simulation is suitable for research on the distribution of oxygen in coalmines. The results also indicated that near the workface spontaneous combustion was more likely to take place in the upper part of the goaf than near the bottom, while further from workface the risk of spontaneous combustion was greater in the lower part of the goaf. These results can be used to develop firefighting approaches for coalmines.

  15. Surface water quality associated with the surface mining of Iowa coal

    Energy Technology Data Exchange (ETDEWEB)

    Gulliford, J.B.; Wildman, R.B.; Payne, L.K.

    1977-11-07

    The findings of an exhaustive study of coal mining and coal preparation industries are reviewed for the purpose of developing limitation guidelines and performance standards. Successful technologies are discussed for treatment of acid mine water collected in settling ponds. A combination of limestone (less expensive, safer to handle, most effective at low pH levels) and lime (more effective in neutralizing at higher pH's) is recommended when cost is an important consideration, as in Iowa mining. We recommend two ponds, with raw water entering the second pond after treatment with limestone/lime on a regulated dose/flow rate with thorough mixing. The second pond would serve a clarifying purpose for settling of the floc of insoluble sulfates and hydroxides. Adequate retention time is important before discharge of the effluent to the receiving stream. We are confident that the effluent from this secondary pond could be expected to meet EPA and DEQ standards if the pH of the treated water were raised to 7 to 9. EPA has documented these performance standards at the mining operations included in their study. The engineering and application costs of this treatment method should be well within reach of Iowa mining companies.

  16. Immediate effect of simulated sand mining on the variation of bacterial parameters in coastal waters of Kalbadevi Bay, Ratnagiri

    Digital Repository Service at National Institute of Oceanography (India)

    Fernandes, C.E.G.; Das, A.; Naik, S.S.; Sharma, R.; LokaBharathi, P.A.

    The variation in bacterial parameters of coastal waters and sediments of Kalbadevi Bay, Ratnagiri, Maharashtra, India was examined for immediate response after simulated mining. Sampling was carried out at suction and disturbance points in the water...

  17. Intervention strategies to eliminate truck-related fatalities in surface coal mining in West Virginia.

    Science.gov (United States)

    Zhang, Meng; Kecojevic, Vladislav

    2016-01-01

    The main objective of this review was to build upon a previous study on the root causes of truck-related fatalities in surface coal mining operations in West Virginia, and to develop intervention strategies to eliminate these fatalities. This review considers a two-pronged approach to accident prevention: one that is fundamental and traditional (safety regulations, training and education, and engineering of the work environment); and one that is innovative and creative (e.g., applying technological advances to better control and eliminate the root causes of accidents). Suggestions for improving current training and education system are proposed, and recommendations are provided on improving the safety of mine working conditions, specifically safety conditions on haul roads, dump sites, and loading areas. We also discuss various currently available technologies that can help prevent haul truck-related fatal accidents. The results of this review should be used by mine personnel to help create safer working conditions and decrease truck-related fatalities in surface coal mining.

  18. Radiological impact of surface water and sediment near uranium mining sites.

    Science.gov (United States)

    Ivanova, K; Stojanovska, Z; Badulin, V; Kunovska, B; Yovcheva, M

    2015-12-01

    The aim of this study is to assess the radiological impact of surface water and sediment around uranium mining sites 20 years after their closing. The areas under observations are 31 former classical underground uranium mining and exploratory sites in Bulgaria, named as objects. The extraction and processing of uranium ores in the Republic of Bulgaria were ended in 1992. To assess the radiological impact of radionuclides field expeditions were performed to sample water and bottom sediment. The migration of uranium through surface water was examined as one of the major pathways for contamination spread. The range of uranium concentration in water flowing from the mining sites was from 0.012 to 6.8 mgU l(-1) with a geometric mean of 0.192 mgU l(-1). The uranium concentrations in water downstream the mining sites were approximately 3 times higher than the background value (upstream). The concentrations of Unat, (226)Ra, (210)Pb, and (232)Th in the sediment of downstream river were higher than those upstream by 3.4, 2.6, 2, and 1.7 times, respectively. The distribution coefficient of uranium reflects its high mobility in most of the sites. In order to evaluate the impact on people as well as site prioritization for more detailed assessment and water management, screening dose assessments were done.

  19. Effects of lignite surface mining on local communities: controversies and areas of negotiation

    Directory of Open Access Journals (Sweden)

    Badera Jarosław

    2017-09-01

    Full Text Available Selecting locations for lignite mining and power generation complexes has been the subject of intense controversy. As a result, there have been many conflicts in society due to environmental and economic concerns. This paper poses the question of how lignite surface mining affects local communities. These effects may be both negative and positive and some of them are intangible. It is very difficult to balance the pros and cons objectively as it depends on the assumed objectives and criteria of the analysis. Different social and economic structures in different communities, and various additional factors, are just some of the reasons why this balance may significantly differ around a country. The authors hold opposing views on the role of lignite in the energy mix and the balance of negative and positive effects that surface mining exerts on local communities. They agree, however, that the most important elements of the societal debate on lignite mining have not yet been adequately studied or presented in public discourse. The authors propose to introduce the procedure of Social Impact Assessment to the Polish legal system. This could be effective as a means to prevent many conflicts in the energy sector and be the best way to reach a compromise.

  20. Suitability of dredged material for reclamation of surface-mined land. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, W.; Van Luik, A.

    1979-12-01

    Eroding ridges of acidic coal-mine spoil in La Salle County, Illinois, were leveled to form a gently-sloped raised plateau. Four test plots were constructed: a control plot and three treatment plots that received a 0.9-m-thick cover of dredged material obtained from the Metropolitan Sanitary District of Greater Chicago. Two treatment plots received lime applications and all plots were seeded with a mixture of grasses. Pressure-vacuum soil water samplers were installed, in duplicate, at two levels in the control plot and at three levels in each treatment plot. The three levels in the treatment plots coincided with dredged material, the dredged-material mine-spoil interface, and the underlying mine spoil. Surface water, soil water, and groundwater were monitored for 29 water-quality parameters for one year. Rainfall, air temperature, runoff, and water-level elevation data were collected also. Detailed analysis of the data indicates that the dredged material used in this study does not adversely affect water quality; it supports abundant plant growth, lessens groundwater contamination, and controls acid runoff. The dredged material is judged to be a suitable material for use in reclamation of surface-mined land.

  1. Hydrogeologic setting and simulation of groundwater flow near the Canterbury and Leadville Mine Drainage Tunnels, Leadville, Colorado

    Science.gov (United States)

    Wellman, Tristan P.; Paschke, Suzanne S.; Minsley, Burke; Dupree, Jean A.

    2011-01-01

    63 percent of the total water budget, respectively). The largest contributions to the water budget were groundwater entering from the upper reaches of the watershed and the hydrologic interaction of the groundwater with the East Fork Arkansas River. Potentiometric surface maps of the simulated model results were generated for depths of 50, 100, and 250 m. The surfaces revealed a positive trend in hydraulic head with land-surface altitude and evidence of increased control on fluid movement by the fault network structure at progressively greater depths in the aquifer. Results of advective particle-tracking simulations indicate that the sets of simulated flow paths for the Canterbury Tunnel and the Leadville Mine Drainage Tunnel were mutually exclusive of one another, which also suggested that no major hydraulic connection was present between the tunnels. Particle-tracking simulations also revealed that although the fault network generally restricted groundwater movement locally, hydrologic conditions were such that groundwater did cross the fault network at many locations. This cross-fault movement indicates that the fault network controls regional groundwater flow to some degree but is not a complete barrier to flow. The cumulative distributions of adjusted age results for the watershed indicate that approximately 30 percent of the flow pathways transmit groundwater that was younger than 68 years old (post-1941) and that about 70 percent of the flow pathways transmit old groundwater. The particle-tracking results are consistent with the apparent ages and mixing ratios developed from the chlorofluorocarbon and tritium results. The model simulations also indicate that approximately 50 percent of the groundwater flowing through the study area was less than 200 years old and about 50 percent of the groundwater flowing through the study area is old water stored in low-permeability geologic units and fault blocks. As a final examination of model response, the conductance

  2. Development of a new mathematical model for prediction of surface subsidence due to inclined coal-seam mining

    Energy Technology Data Exchange (ETDEWEB)

    Asadi, A.; Shahriar, K.; Goshtasbi, K.; Najm, K. [Islam Azad University, Tehran (Iran). Dept. of Mining Engineering

    2005-01-01

    Subsidence phenomenon as an unwanted consequence of underground mining can cause problems for environment and surface structures in mine area. Surface subsidence prediction for inclined and steep seams has been given less attention than horizontal seams due to the difficulties involved in the extraction of such coal-seams. This paper introduces a new profile function method for prediction of surface subsidence due to inclined coal-seam mining. The results of calculation with the new function indicate that the predicted value has good agreement with the measured data.

  3. Localization of Surface or Near-surface Drifting Mines for Unmanned Systems in the Persian Gulf

    Science.gov (United States)

    2012-06-01

    many cases of interdiction mining, the minefields are covertly laid off enemy ports or assets. Once such a minefield is discovered , the port in...few days, and density-driven currents or thermohaline circulation varies over a period of weeks. The strong tidal currents create a bottom, mechanical

  4. Astronaut Neil Armstrong participates in simulation of moon's surface

    Science.gov (United States)

    1969-01-01

    Astronaut Neil A. Armstrong, wearing an Extravehicular Mobility Unit, deploys a lunar surface television camera during lunar surface simulation training in bldg 9, Manned Spacecraft Center. Armstrong is the prime crew commander of the Apollo 11 lunar landing mission.

  5. Geomorphic evaluation of erosional stability at reclaimed surface mines in northwestern Colorado. Water Resources Investigation

    International Nuclear Information System (INIS)

    Elliott, J.G.

    1990-01-01

    The report identifies geomorphic, pedologic, vegetation, and hydrologic conditions that are associated with erosion of reclaimed surface-mined lands in northwestern Colorado. The report also presents methods for determining the appropriate values of geomorphic variables that can be manipulated during reclamation to increase erosional stability. A section on geomorphic principles associated with erosion of reclaimed land surfaces is designed for use as a primer by mine personnel and reclamation planners. The areas of interest in the study were those that were reclaimed under jurisdiction of current (1988) SMCRA reclamation regulations, yet were still affected by relatively rapid erosion rates several years after reclamation activities were completed. Geomorphic, pedologic, vegetation, and hydrologic data were collected onsite and from topographic maps. Data from reclaimed areas undergoing accelerated erosion were compared with data from reclaimed areas undergoing minimal erosion to identify conditions that controlled erosion on reclaimed surface-mined lands and to identify some postmining equilibrium landform characteristics. These data also were used to develop threshold relations

  6. Developments in the analysis of footwall slopes in surface coal mining

    Energy Technology Data Exchange (ETDEWEB)

    Stead, D.; Eberhardt, E. [University of Saskatchewan, Saskatoon, SK (Canada). Dept. of Geological Sciences

    1997-03-01

    Surface mining of coal, particularly in areas of mountainous topography, often involves the formation of extensive footwall slopes parallel to the strata dip. Due to structural deformation steep dips on the limbs of folds may be encountered in association with thrust faults, jointing and residual shear strength conditions. Such an environment necessitates a rigorous assessment of footwall stability in order to ensure safe and economic exploitation of the coal. This paper provides a detailed review of the factors influencing footwall slope instability in surface coal mining and the major instability mechanisms. The analysis of footwalls in the design stage and the back analysis of footwall slope failures has in general been undertaken using predominantly two-dimensional limit equilibrium techniques often incorporating a simplistic elastic column analysis. The application of numerical modelling techniques to surface coal mine footwalls has received little attention. Here the authors illustrate the potential for investigating footwall failure mechanisms and stability using the distinct element method and other modelling techniques. 44 refs., 21 figs., 2 tabs.

  7. Similar simulation study on the characteristics of the electric potential response to coal mining

    Science.gov (United States)

    Niu, Yue; Li, Zhonghui; Kong, Biao; Wang, Enyuan; Lou, Quan; Qiu, Liming; Kong, Xiangguo; Wang, Jiali; Dong, Mingfu; Li, Baolin

    2018-02-01

    An electric potential (EP) can be generated during the failure process of coal and rock. In this article, a similar physical model of coal rock was built and the characteristics of the EP responding to the process of coal mining were studied. The results showed that, at the early mining stage, the structure of coal rock strata were stable in the simulation model, the support stress of overlying coal rock strata was low and the maximum subsidence was little, while the EP change was less. With the advancement of the working face, the support stress of the overlying coal rock strata in the mined-out area changed dramatically, the maximum subsidence increased constantly, the deformation and destruction were aggravated, and cracks expanded continuously. Meanwhile, the EP response was significant with fluctuation. When significant macro damage appeared in coal rock strata, the EP signal fluctuation was violent. The overlying coal rock strata were influenced by gravity and mining activity. During the mining process, the crack growth and the friction, together with slip between coal and rock particles, resulted in the response of EP. The change in EP was closely related to the damage state and stress distribution of the coal rock strata. EP monitoring has the advantages of accurate reflection and strong anti-interference in the field. Therefore, with further study, an EP monitoring method could be applied for monitoring and early warning of coal and rock dynamic disaster, and risk evaluation in the future. The strength of the EP and its fluctuation degree could serve as the key discrimination indexes.

  8. New model for mines and transportation tunnels external dose calculation using Monte Carlo simulation

    International Nuclear Information System (INIS)

    Allam, Kh. A.

    2017-01-01

    In this work, a new methodology is developed based on Monte Carlo simulation for tunnels and mines external dose calculation. Tunnels external dose evaluation model of a cylindrical shape of finite thickness with an entrance and with or without exit. A photon transportation model was applied for exposure dose calculations. A new software based on Monte Carlo solution was designed and programmed using Delphi programming language. The variation of external dose due to radioactive nuclei in a mine tunnel and the corresponding experimental data lies in the range 7.3 19.9%. The variation of specific external dose rate with position in, tunnel building material density and composition were studied. The given new model has more flexible for real external dose in any cylindrical tunnel structure calculations. (authors)

  9. Simulation modeling and tracing optimal trajectory of robotic mining machine effector

    Science.gov (United States)

    Fryanov, VN; Pavlova, LD

    2017-02-01

    Within the framework of the robotic coal mine design for deep-level coal beds with the high gas content in the seismically active areas in the southern Kuzbass, the motion path parameters for an effector of a robotic mining machine are evaluated. The simulation model is meant for selection of minimum energy-based optimum trajectory for the robot effector, calculation of stresses and strains in a coal bed in a variable perimeter shortwall in the course of coal extraction, determination of coordinates of a coal bed edge area with the maximum disintegration of coal, and for choice of direction of the robot effector to get in contact with the mentioned area and to break coal at the minimum energy input. It is suggested to use the model in the engineering of the robot intelligence.

  10. Monte Carlo Simulation of Protein Adsorption on Energetically Heterogeneous Surfaces

    OpenAIRE

    Danwanichakul, Panu

    2014-01-01

    The modified triangular-well potential model was applied to incorporate the effect of surface energy on the adsorption of particles or proteins on energetically heterogeneous surfaces. The method is convenient in simulating the adsorption on heterogeneous surface of which different region possesses different free energy. Spherical particles with attractive forces were added on the surface and underwent surface diffusion before they were quenched in place. It was seen that the ratio of surface...

  11. Factors affecting the development of a surface coal mine safety and training program in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Huber, D.W.; Gilliss, A.M.

    1982-09-01

    During the past decade, a general awareness of the need for and subsequent development of increased safety in United States coal mines has taken place. Government and industry alike were stimulated into accelerating their actions through unacceptable accident statistics and costs (in terms of human misery and dollar values). Those of us who work in the United States coal industry are aware of the development of governmental controls on mine safety. Both Federal and State regulations have placed increased responsibility upon mine owners and operators to insure a safe working environment and to provide training for miners. No other industrial group of workers has received such attention or, in our opinion, deserves it more. It should be pointed out that surface coal mines are safe places to work, considering the size of equipment, depths of excavation, use of high voltage electricity, explosives, and other hazards associated with continuous operations in all weather conditions. United States surface miners are, we believe, in a far safer environment while working at the mine than they are while driving to and from the mine, or performing a host of other non-mine related activities. While it is not the purpose of this paper to argue the effectiveness of governmental regulations, a brief review of the Federal control of mine safety will be made. Along with regulations, management expertise has also been developed. Since coal mining is an expensive, complex business, management sophistication has increased and with this enlightened viewpoint, all aspects of the business have been and are being analyzed. The impact management has on mine safety will also be discussed. Finally, and as the main function of this paper, we will describe management's use of principles and courses of action used to develop the safety function at a large volume surface lignite coal mine in the United States.

  12. Rock mass response to strong ground motion generated by mining induced seismic events and blasting observed at the surface of the excavations in deep level gold mines in South Africa

    Science.gov (United States)

    Milev, Alexander; Durrheim, Ray; Ogasawara, Hiroshi

    2014-05-01

    The strong ground motion generated by mining induced seismic events was studied to characterize the rock mass response and to estimate the site effect on the surface of the underground excavations. A stand-alone instruments, especially designed for recording strong ground motions, were installed underground at a number of deep level gold mines in South Africa. The instruments were recording data at the surface of the stope hangingwalls. A maximum value of 3 m/s was measured. Therefore data were compared to the data recorded in the solid rock by the mine seismic networks to determine the site response. The site response was defined as the ratio of the peak ground velocity measured at the surface of the excavations to the peak ground velocity inferred from the mine seismic data measured in the solid rocks. The site response measured at all mines studied was found to be 9 ± 3 times larger on average. A number of simulated rockbursts were conducted underground in order to estimate the rock mass response when subjected to extreme ground motion and derive the attenuation factors in near field. The rockbursts were simulated by means of large blasts detonated in solid rock close to the sidewall of a tunnel. The numerical models used in the design of the simulated rockbursts were calibrated by small blasts taking place at each experimental site. A dense array of shock type accelerometers was installed along the blasting wall to monitor the attenuation of the strong ground motion as a function of the distance from the source. The attenuation of the ground motion was found to be proportional to the distance from the source following R^-1.1 & R^-1.7 for compact rock and R^-3.1 & R^-3.4 for more fractured rock close to the surface of the tunnel. In addition the ground motion was compared to the quasi-static deformations taking place around the underground excavations. The quasi-static deformations were measured by means of strain, tilt and closure. A good correspondence

  13. Emission factors for wind erosion of exposed aggregates at surface coal mines

    Energy Technology Data Exchange (ETDEWEB)

    Cowherd, C.

    1982-06-01

    The information presented in this paper is directed to those interested in inventorying dust emissions generated by wind erosion of exposed aggregates at surface coal mines. A testing program is described which entailed the use of a portable wind tunnel and an isokinetic sampling system to measure windblown dust emissions from coal and overburden materials at three western mine sites. Test measurements consisted of particle mass emission rates and size distributions for various control wind speeds and times after the initiation of wind erosion. The results indicate that natural surface crusts are very effective in mitigating suspended dust emissions and that a given surface has a finite potential for wind erosion subsequent to mechanical disturbance. Test data are used to develop a predictive emission factor equation which relates emission rate (per unit surface area) to the frequency of disturbance and the erosion potential corresponding to the fastest mile of wind for the period between disturbances. This equation can be used directly for flat surfaces or it can be coupled with an analysis of wind flow patterns around elevated storage piles to develop dust emission estimates for overall pile erosion.

  14. 30 CFR 800.17 - Bonding requirements for underground coal mines and long-term coal-related surface facilities and...

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Bonding requirements for underground coal mines... REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS BOND AND INSURANCE REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS UNDER REGULATORY PROGRAMS § 800.17 Bonding requirements for...

  15. Possible use of wetlands in ecological restoration of surface mined lands

    International Nuclear Information System (INIS)

    Atkinson, R.B.; Cairns, J. Jr.

    1994-01-01

    Surface mining for coal has dramatically altered millions of hectares throughout the Appalachian region of eastern North America. Flat benches and vertical high walls have replaced well-drained slopes, and wetlands have developed 'accidentally' on abandoned benches. Surface mining is continuing in this region, but new regulations do not include specifications for wetland construction in the reclamation process. Recent research has suggested that many ecosystem services appropriate for the Appalachian landscape could be performed by constructed wetlands. Inclusion of wetland construction in a reclamation plan could lead to a net increase in wetland acreage locally, as well as offset the loss of natural and/or accidental wetlands that are constructed to enhance nontreatment goals in reclamation. Study sites included 14 emergent wetlands in Wise County, Virginia. Sampling in June and August detected a total of 94 species in 36 vascular plant facilities. Obligate wetlands species, species that occur in wetlands over 99% of the time, were found in all 14 sites and included 26 species. The presence of so many wetland species without intentional management efforts suggests that wetland establishment could become a common component of mine reclamation. 18 refs., 2 tabs

  16. An inexpensive underwater mine countermeasures simulator with real-time 3D after action review

    Directory of Open Access Journals (Sweden)

    Robert Stone

    2016-10-01

    Full Text Available This paper presents the results of a concept capability demonstration pilot study, the aim of which was to investigate how inexpensive gaming software and hardware technologies could be exploited in the development and evaluation of a simulator prototype for training Royal Navy mine clearance divers, specifically focusing on the detection and accurate reporting of the location and condition of underwater ordnance. The simulator was constructed using the Blender open source 3D modelling toolkit and game engine, and featured not only an interactive 3D editor for underwater scenario generation by instructors, but also a real-time, 3D After Action Review (AAR system for formative assessment and feedback. The simulated scenarios and AAR architecture were based on early human factors observations and briefings conducted at the UK's Defence Diving School (DDS, an organisation that provides basic military diving training for all Royal Navy and Army (Royal Engineers divers. An experimental pilot study was undertaken to determine whether or not basic navigational and mine detection components of diver performance could be improved as a result of exposing participants to the AAR system, delivered between simulated diving scenarios. The results suggest that the provision of AAR was accompanied by significant performance improvements in the positive identification of simulated underwater ordnance (in contrast to non-ordnance objects and on participants' description of their location, their immediate in-water or seabed context and their structural condition. Only marginal improvements were found with participants' navigational performance in terms of their deviation accuracies from a pre-programmed expert search path. Overall, this project contributes to the growing corpus of evidence supporting the development of simulators that demonstrate the value of exploiting open source gaming software and the significance of adopting established games design

  17. Ra-226 collective dosimetry for surface waters in the uranium mining region of Pocos de Caldas

    International Nuclear Information System (INIS)

    Paschoa, A.S.; Sigaud, G.M.; Montenegro, E.C.; Baptista, G.B.

    1980-01-01

    Graphs of the collective dose equivalent for the whole body, bone, gastro-intestinal tract (lower large intestine), kidneys, and liver, via the pathways of drinking water and ingestion of food grown in irrigated fields are presented as a function of the 226 Ra concentrations in the surface waters of the Pocos de Caldas region. The collective dose equivalent calculated from the 226 Ra concentrations measured in the baseline studies are compared with those collective dose equivalent estimated from the projected higher 226 Ra concentrations in the river waters. The 226 Ra concentrations in river waters of the region are expected to be enhanced due to 226 Ra releases from uranium mining and milling operations. The dose equivalent commitment for the exposed population for the referred pathways is also estimated for the contribution of the mine during its predicted time of operation. The assumptions for the dose calculations are presented and the results obtained are discussed. (H.K.)

  18. Treatment of sulphated water of surface origin produced by an open pit coal mine

    Directory of Open Access Journals (Sweden)

    Alan Campos-Sánchez

    2016-12-01

    Full Text Available The purpose of this study was to select the most suitable method of treatment of sulfated water produced by an open pit coal mine in Venezuela. Samples of water taken on surface, middle and bottom of water bodies in three areas were subjected to basic, gravimetric, volumetric and colorimetric analysis. The results indicated that the pH is within limits permitted by current environmental regulations, while total suspended solids, total dissolved solids, and sulfates exceed the normed values. The aerobic wetland method was selected as the most efficient for the removal of sulfates, depending on the physicochemical characteristics of the sulphated waters from the mine and because they are systems that use natural energy to purify water, its construction and maintenance costs Is significantly inferior to the conventional treatments and because, being replicas of natural ecosystems, they are integrated to the environment.

  19. An novel frequent probability pattern mining algorithm based on circuit simulation method in uncertain biological networks

    Science.gov (United States)

    2014-01-01

    Background Motif mining has always been a hot research topic in bioinformatics. Most of current research on biological networks focuses on exact motif mining. However, due to the inevitable experimental error and noisy data, biological network data represented as the probability model could better reflect the authenticity and biological significance, therefore, it is more biological meaningful to discover probability motif in uncertain biological networks. One of the key steps in probability motif mining is frequent pattern discovery which is usually based on the possible world model having a relatively high computational complexity. Methods In this paper, we present a novel method for detecting frequent probability patterns based on circuit simulation in the uncertain biological networks. First, the partition based efficient search is applied to the non-tree like subgraph mining where the probability of occurrence in random networks is small. Then, an algorithm of probability isomorphic based on circuit simulation is proposed. The probability isomorphic combines the analysis of circuit topology structure with related physical properties of voltage in order to evaluate the probability isomorphism between probability subgraphs. The circuit simulation based probability isomorphic can avoid using traditional possible world model. Finally, based on the algorithm of probability subgraph isomorphism, two-step hierarchical clustering method is used to cluster subgraphs, and discover frequent probability patterns from the clusters. Results The experiment results on data sets of the Protein-Protein Interaction (PPI) networks and the transcriptional regulatory networks of E. coli and S. cerevisiae show that the proposed method can efficiently discover the frequent probability subgraphs. The discovered subgraphs in our study contain all probability motifs reported in the experiments published in other related papers. Conclusions The algorithm of probability graph isomorphism

  20. Laboratory rainfall simulator studies of selected open-cut coal mine overburden spoils from Central Queensland

    Energy Technology Data Exchange (ETDEWEB)

    Evans, K.G.; Loch, R.J.; Aspinall, T.O.; Bell, L.C. [Eros and Hydrology Group, Jabiru, NT (Australia)

    1997-05-01

    Data on the erodibility of overburden spoils resulting from open-cut coal mining are limited. These data are required to derive parameters for erosion prediction models which can be used in the design of re-formed landscapes after mining. In this study, laboratory rainfall simulation data were used to derive CREAMS (Chemicals, Runoff and Erosion from Agricultural Management Systems) interfill erodibility parameters K and n{sub bov} for Central Queensland coal mine overburden spoils. For the spoils studied, K values ranged from 0.0111 to 0.1398 Mg ha h/(ha MJ mm) and n{sub bov} values ranged from 0.0004 to 0.0081. Sediment yield was transport controlled. Results for 1 spoil, South Blackwater Terang, showed that total soil loss increased linearly with slope, and both K and n{sub bov} varied non-linearly with slope. If a constant set of K and n{sub bov} values is used in modelling, CREAMS over-predicts spoil loss for slopes greater than that for which the parameter values were determined, and under-predicts spoil loss for slopes less than that for which the parameter values were determined.

  1. Simulation of surface evolution during ion bombardment

    International Nuclear Information System (INIS)

    Katardjiev, I.V.

    1988-01-01

    Some theoretical aspects of surface topography evolution during ion beam erosion are discussed. In particular, the theory of characteristics is considered in some detail and its limitations pointed out. Further theoretical development based on the Huygens principle of wave propagation is discussed also with respect to numerical evaluation of surface evolution. A new numerical algorithm based on the contemporary theoretical concepts of surface and edge propagation is proposed and compared with existing numerical models and theoretical expectations

  2. Modeling and Simulating Airport Surface Operations with Gate Conflicts

    Science.gov (United States)

    Zelinski, Shannon; Windhorst, Robert

    2017-01-01

    The Surface Operations Simulator and Scheduler (SOSS) is a fast-time simulation platform used to develop and test future surface scheduling concepts such as NASAs Air Traffic Demonstration 2 of time-based surface metering at Charlotte Douglas International Airport (CLT). Challenges associated with CLT surface operations have driven much of SOSS development. Recently, SOSS functionality for modeling hardstand operations was developed to address gate conflicts, which occur when an arrival and departure wish to occupy the same gate at the same time. Because surface metering concepts such as ATD2 have the potential to increase gates conflicts as departure are held at their gates, it is important to study the interaction between surface metering and gate conflict management. Several approaches to managing gate conflicts with and without the use of hardstands were simulated and their effects on surface operations and scheduler performance compared.

  3. Windborne transport and surface enrichment of arsenic in semi-arid mining regions: Examples from the Mojave Desert, California

    Science.gov (United States)

    Kim, Christopher S.; Anthony, Tyler L.; Goldstein, Daniel; Rytuba, James J.

    2014-09-01

    Gold and silver mining conducted throughout the state of California has left an environmental legacy of exposed mine wastes containing elevated levels of toxic metals and metalloids including arsenic (As), a known carcinogen. These mine tailings, particularly the fine-grained size fractions, are susceptible to weathering and windborne transport, significantly increasing the spatial extent of contamination in topsoils and potential exposure of humans to toxic metal(loid)s. Depth-based field sampling of soils surrounding several abandoned mines in the Mojave Desert (Southern CA) have identified an exponential decline in As soil enrichment with both depth and increasing distance from tailings piles to the east, consistent with prevailing west-to-east wind directions. In vitro extraction studies using a phagolysosomal simulant fluid (PSF), mimicking the inhalation of the most finely sieved size fraction of selected samples (⩽20 μm), indicate that initial solid As concentration is the strongest indicator in predicting the concentration of As released in the lung. When extraction data are incorporated into exposure risk assessment calculations, the majority of samples investigated exceed both cancer risk thresholds and non-cancer-related minimal risk levels (MRLs) based on long-term chronic exposure to airborne mine tailings dusts. This suggests that long-term residents of communities located close to these abandoned mine sites, especially those who reside downwind (i.e. east) of mine tailings piles, face possible health effects due to the inhalation of fine-grained mine tailings mobilized through aeolian processes.

  4. Habitat manipulation influences northern bobwhite resource selection on a reclaimed surface mine

    Science.gov (United States)

    Brooke, Jarred M.; Peters, David C.; Unger, Ashley M.; Tanner, Evan P.; Harper, Craig A.; Keyser, Patrick D.; Clark, Joseph D.; Morgan, John J.

    2015-01-01

    More than 600,000 ha of mine land have been reclaimed in the eastern United States, providing large contiguous tracts of early successional vegetation that can be managed for northern bobwhite (Colinus virginianus). However, habitat quality on reclaimed mine land can be limited by extensive coverage of non-native invasive species, which are commonly planted during reclamation. We used discrete-choice analysis to investigate bobwhite resource selection throughout the year on Peabody Wildlife Management Area, a 3,330-ha reclaimed surface mine in western Kentucky. We used a treatment-control design to study resource selection at 2 spatial scales to identify important aspects of mine land vegetation and whether resource selection differed between areas with habitat management (i.e., burning, disking, herbicide; treatment) and unmanaged units (control). Our objectives were to estimate bobwhite resource selection on reclaimed mine land and to estimate the influence of habitat management practices on resource selection. We used locations from 283 individuals during the breeding season (1 Apr–30 Sep) and 136 coveys during the non-breeding season (1 Oct–Mar 31) from August 2009 to March 2014. Individuals were located closer to shrub cover than would be expected at random throughout the year. During the breeding season, individuals on treatment units used areas with smaller contagion index values (i.e., greater interspersion) compared with individuals on control units. During the non-breeding season, birds selected areas with greater shrub-open edge density compared with random. At the microhabitat scale, individuals selected areas with increased visual obstruction >1 m aboveground. During the breeding season, birds were closer to disked areas (linear and non-linear) than would be expected at random. Individuals selected non-linear disked areas during winter but did not select linear disked areas (firebreaks) because they were planted to winter wheat each fall and

  5. Numerical simulation of creep closure of deep potash mines (with application to waste isolation)

    Energy Technology Data Exchange (ETDEWEB)

    Munson, D.E.; Dawson, P.R.

    1980-07-01

    In this work, numerical simulation of the mechanical response of a deep mine opening in potash is shown to match measured room closures to within a factor of two. In this case, the calculated closure rates after eight years are within 25 to 75 percent of those measured. In making the calculations, a constitutive model for creep, as determined from laboratory triaxial tests of salt and short cylinder compressive tests of potash, was incorporated into a coupled thermal-mechanical fluid flow code, COUPLEFLO. The model is a multimechanism formulation of thermally activated processes acting in parallel. Because the field tests were well-documented, two-dimensional configurations and because the constitutive model was uniquely determined by laboratory data, the agreement between calculations and field data for these significant time durations is a first step in verification of the simulation technique. Application of the model and numerical methods presented here can be used to understand deformation in deep potash mines and, very importantly, to aid also in design of the waste isolation and petroleum storage facilities.

  6. Numerical simulation of creep closure of deep potash mines (with application to waste isolation)

    International Nuclear Information System (INIS)

    Munson, D.E.; Dawson, P.R.

    1980-07-01

    In this work, numerical simulation of the mechanical response of a deep mine opening in potash is shown to match measured room closures to within a factor of two. In this case, the calculated closure rates after eight years are within 25 to 75 percent of those measured. In making the calculations, a constitutive model for creep, as determined from laboratory triaxial tests of salt and short cylinder compressive tests of potash, was incorporated into a coupled thermal-mechanical fluid flow code, COUPLEFLO. The model is a multimechanism formulation of thermally activated processes acting in parallel. Because the field tests were well-documented, two-dimensional configurations and because the constitutive model was uniquely determined by laboratory data, the agreement between calculations and field data for these significant time durations is a first step in verification of the simulation technique. Application of the model and numerical methods presented here can be used to understand deformation in deep potash mines and, very importantly, to aid also in design of the waste isolation and petroleum storage facilities

  7. Hydrology and geochemistry of a surface coal mine in northwestern Colorado

    Science.gov (United States)

    Williams, R.S.; Clark, G.M.

    1994-01-01

    The hydrology and geochemistry of a reclaimed coal mine in northwestern Colorado were monitored during water years 1988 and 1989. Some data also were collected in water years 1987 and 1990. This report describes (1) the sources of hydrologic recharge to and discharge from reclaimed spoil, (2) the relative contributions of recharge to the reclaimed spoil aquifer from identified source waters and the rate of water movement from those sources to the reclaimed spoil, and (3) the geochemical reactions that control water quality in reclaimed spoil. The study area was at a dip-slope coal mine encompassing about 7 square miles with land slopes of varying aspect. The area was instrumented and monitored at five sites; two sites had unmined and reclaimed- spoil areas adjacent to each other and three sites were unmined. The mined areas had been reclaimed. Instrumentation at the study sites included 1 climate station, 3 rain gages, 19 soil-water access tubes, 2 lysimeters, 18 wells completed in bedrock, 7 wells completed in reclaimed spoil, and 2 surface- water gaging stations. The results of the study indicate that the reclaimed spoil is recharged from surface recharge and underburden aquifers. Discharge, as measured by lysimeters, was about 3 inches per year and occurred during and after snowmelt. Hydraulic-head measurements indicated a potential for ground-water movement from deeper to shallower aquifers. Water levels rose in the reclaimed-spoil aquifer and spring discharge at the toe of the spoil slopes increased rapidly in response to snowmelt. Water chemistry, stable isotopes, geochemical models, and mass-balance calculations indicate that surface recharge and the underburden aquifers each contribute about 50 percent of the water to the reclaimed-spoil aquifers. Geochemical information indicates that pyrite oxidation and dissolution of carbonate and efflorescent sulfate minerals control the water chemistry of the reclaimed-spoil aquifer.

  8. Simulation Tool for GNSS Ocean Surface Reflections

    OpenAIRE

    Høeg, Per; von Benzon, Hans-Henrik; Durgonics, Tibor

    2015-01-01

    GNSS coherent and incoherent reflected signals have the potential of deriving large scale parameters of ocean surfaces, as barotropic variability, eddy currents and fronts, Rossby waves, coastal upwelling, mean ocean surfaceheights, and patterns of the general ocean circulation. In the reflection zone the measurements may deriveparameters as sea surface roughness, winds, waves, heights and tilts from the spectral measurements. Previous measurements from the top of mountains and airplanes have...

  9. Prime farmland disturbance from coal surface mining in the corn belt, 1980-2000

    Energy Technology Data Exchange (ETDEWEB)

    Bernard, D.P.

    1979-09-01

    The five midwestern states that make up the Corn Belt farm production region - Illinois, Indiana, Iowa, Missouri, and Ohio - contain about 110 billion tons of coal reserves (19% of which are surface mineable) and 110 million acres of arable land (69% of which are prime farmlands). In 1975, this region was the site of 21% of the nation's total coal production and 50% of the nation's corn and soybean harvest. Because corn and soybeans are key elements in US foreign trade and because nearly two-thirds of the regional coal production is from surface coal mines, it is important to understand the potential conflicts that may arise between the coal and agricultural industries in the Corn Belt. This report presents background data on the coal and agricultural industries in the Corn Belt states, along with the results of a quantitative analysis of the potential disruption of land and associated prime farmland due to future coal surface mining activity in the region. Estimates of potential land dusruptions indicate that 452,000 acres of land, including 127,000 acres of prime farmland, could be disturbed in the period 1980-2000. Additionally, the data indicate that certain counties in the Corn Belt states may experience impacts significantly greater than the regional average would suggest.

  10. Derived surface contamination limits for the uranium mining and milling industry

    International Nuclear Information System (INIS)

    Ching, S.H.

    1984-10-01

    Derived Surface Contamination Limits (DSCL) are proposed for the control of surface contamination at the work place for the uranium mining and milling industry. They have been derived by a method incorporating recent ICRP recommendations and consideration of the radiation exposure pathways of ingestion, inhalation and external irradiation of the basal layer of skin. A generalized DSCL of 10 5 Bq/m 2 of beta activity is recommended for all contaminants likely to be found in uranium mine and mill workplaces except for fresh uranium concentrates. In the latter case, the DSCL is expressed in terms of alpha activity because the ratio of beta to alpha activities for fresh uranium concentrates is variable; the beta activity increases with the ingrowth of U-238 daughter products (Th-234 and Pa-234m) until secular equilibrium is re-established in about six months. A surface contamination limit of 10 4 Bq/m 2 of beta activity is proposed for the release of non-porous materials and equipment with no detectable loose contamination to the public domain

  11. Effect of coal mine dust and clay extracts on the biological activity of the quartz surface

    Energy Technology Data Exchange (ETDEWEB)

    Stone, V.; Jones, R.; Rollo, K.; Duffin, R.; Donaldson, K.; Brown, D.M. [Napier University, Edinburgh (United Kingdom). School of Life Science

    2004-04-01

    Modification of the quartz surface by aluminum salts and metallic iron have been shown to reduce the biological activity of quartz. This study aimed to investigate the ability of water soluble extracts of coal mine dust (CMD), low aluminum clays (hectorite and montmorillonite) and high aluminum clays (attapulgite and kaolin) to inhibit the reactivity of the quartz surface. DQ12 induced significant haemolysis of sheep erythrocytes in vitro and inflammation in vivo as indicated by increases in the total cell numbers, neutrophil cell numbers, MIP-2 protein and albumin content of bronchoalveolar lavage (BAL) fluid. Treatment of DQ12 with CMD extract prevented both haemolysis and inflammation. Extracts of the high aluminum clays (kaolin and attapulgite) prevented inhibition of DQ12 induced haemolysis, and the kaolin extract inhibited quartz driven inflammation. DQ12 induced haemolysis by coal mine dust and kaolin extract could be prevented by pre-treatment of the extracts with a cation chellator. Extracts of the low aluminum clays (montmorillonite and hectorite) did not prevent DQ12 induced haemolysis, although the hectorite extract did prevent inflammation. These results suggest that CMD, and clays both low and rich in aluminum, all contain soluble components (possibly cations) capable of masking the reactivity of the quartz surface.

  12. Arsenic Concentration in the Surface Water of a Former Mining Area: The La Junta Creek, Baja California Sur, Mexico

    Science.gov (United States)

    Imaz Lamadrid, Miguel; Acosta Vargas, Baudilio

    2018-01-01

    The mining activity in the San Antonio-El Triunfo district, located in a mountainous region at 60 km southeast of La Paz, occured for more than 250 years and left behind severe contamination of soils and riverbed sediments which led to elevated concentrations of arsenic and other trace elements in the surface- and groundwater of the region. Although the main mining activity ended around 1911, contamination is still beeing distributed, especially from left behind tailings and mine waste piles. The contamination levels in the groundwater have been reported in several studies, but there is little information available on the surface water quality, and especially the temporal variation. In this study, we analyzed the surface water of the La Junta creek, in the southern part of the San Antonio-El Triunfo mining district. The working hypothesis was that by means of a spatial analysis of surface water and shallow groundwater, in combination with the temporal observation of the concentrations in runoff water, the effects of different sources of arsenic (natural geogene anomalies, due to historic mining activity, and hydrothermal related impact) in the La Junta creek can be recognized. This present study revealed that historic mining activity caused a mojor impact of arsenic but less contamination was observed than in the northern part of the district and elevated arsenic concentrations in stream water generally occurred during times of low streamflow. PMID:29498700

  13. Diagnostic measurements on the great machines conditions of lignite surface mines

    Energy Technology Data Exchange (ETDEWEB)

    Helebrant, F.; Jurman, J.; Fries, J. [Technical University of Ostrava, Ostrava-Poruba (Czech Republic)

    2005-07-01

    An analysis of the diagnosis of loading and service dependability of a rail-mounted excavator used in surface lignite mining is described. Wheel power vibrations in electric motor bearings and electric motor input bearings to the gearbox were measured in situ, in horizontal, vertical, and axial directions. The data were analyzed using a mathematical relationship. The results are presented in a loading diagram that shows the deterioration and the acceptable lower bound of machine conditions over time. Work is continuing. 5 refs., 1 fig.

  14. Numerical modelling of buckling and ploughing slope instability in surface coal mining

    Energy Technology Data Exchange (ETDEWEB)

    Eberhardt, E.; Stead, D. (University of Saskatchewan, Saskatoon, SK (Canada). Dept. of Geological Sciences)

    1993-01-01

    Buckling and ploughing are characteristic failure mechanisms affecting the footwall slopes of surface coal mines. These failures may cause large losses in production, pose serious safety hazards and necessitate extensive deformation monitoring schemes. A brief survey of the factors influencing buckling and ploughing failures is presented based on a detailed examination of the published literature. A critical review of conventional methods of analysis: two-dimensional limit equilibrium, Euler theory, three-hinge buckling and physical modelling, is undertaken. Preliminary results of numerical modelling using finite difference and distinct element techniques are presented using a typical footwall slope and a selected case history. 16 refs., 5 figs., 1 tab.

  15. The development of WIPPVENT, a windows based interactive mine ventilation simulation software program at the Waste Isolation Pilot Plant

    International Nuclear Information System (INIS)

    McDaniel, K.H.

    1995-01-01

    An interactive mine ventilation simulation software program (WIPPVENT) was developed at the Waste Isolation Pilot Plant (WIPP). The WIPP is a US Department of Energy (DOE) research and development project located near Carlsbad, New Mexico. The facility is designed to provide a permanent, safe underground disposal of US defense generated transuranic waste in bedded salt. In addition to it's regular functions, the underground ventilation system is engineered to prevent the uncontrolled spread of radioactive materials in the unlikely event of a release. To enhance the operability system, Westinghouse Electric Corporation has developed an interactive mine ventilation simulation software program (WIPPVENT). While WIPPVENT includes most of the functions of the commercially available simulation program VNETPC (copyright 1991 Mine Ventilation Services, Inc.), the user interface has been completely rewritten as a Windows reg-sign application and screen graphics have been added. WIPPVENT is designed to interact with the WIPP ventilation monitoring systems through the site wide Central Monitoring System

  16. Development of thermodynamically-based models for simulation of hydrogeochemical processes coupled to channel flow processes in abandoned underground mines

    Energy Technology Data Exchange (ETDEWEB)

    Kruse, N.A., E-mail: natalie.kruse@ncl.ac.uk [Sir Joseph Swan Institute for Energy Research, Newcastle University, Newcastle upon Tyne NE1 7RU (United Kingdom); Younger, P.L. [Sir Joseph Swan Institute for Energy Research, Newcastle University, Newcastle upon Tyne NE1 7RU (United Kingdom)

    2009-07-15

    Accurate modeling of changing geochemistry in mine water can be an important tool in post-mining site management. The Pollutant Sources and Sinks in Underground Mines (POSSUM) model and Pollutant Loadings Above Average Pyrite Influenced Geochemistry POSSUM (PLAYING POSSUM) model were developed using object-oriented programming techniques to simulate changing geochemistry in abandoned underground mines over time. The conceptual model was created to avoid significant simplifying assumptions that decrease the accuracy and defensibility of model solutions. POSSUM and PLAYING POSSUM solve for changes in flow rate and depth of flow using a finite difference hydrodynamics model then, subsequently, solve for geochemical changes at distinct points along the flow path. Geochemical changes are modeled based on a suite of 28 kinetically controlled mineral weathering reactions. Additional geochemical transformations due to reversible sorption, dissolution and precipitation of acid generating salts and mineral precipitation are also simulated using simplified expressions. Contaminant transport is simulated using a novel application of the Random-Walk method. By simulating hydrogeochemical changes with a physically and thermodynamically controlled model, the 'state of the art' in post-mining management can be advanced.

  17. Feasibility of a continuous surface mining machine using impact breakers. First quarterly report, October 1-December 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, A. T.

    1980-01-01

    This is the first quarterly report on the efforts to evaluate the feasibility of excavating coal and overburden from surface mines using impact breakers. The initial stages of the project are devoted to a literature search, equipment selection, test site selection, and conceptual test system design. Hence, this report details the progress made in these areas; the next quarter will see the finalization of Phase I. Included as appendices to this report are FMA internal reports on the individual mines visited. These reports are the basis of the test site selection, and have been censored here to remove data the mine operators deemed as confidential.

  18. Soil-characterization and soil-amendment use on coal surface mine lands: An annotated bibliography. Information Circular/1991

    International Nuclear Information System (INIS)

    Norland, M.R.; Veith, D.L.

    1991-01-01

    The U.S. Bureau of Mines Report on United States and Canadian Literature pertaining to soil characterization and the use of soil amendments as a part of the reclamation process of coal surface-mined lands contains 1,280 references. The references were published during the 1977 to 1988 period. Each reference is evaluated by keywords, providing the reader with a means of rapidly sorting through the references to locate those articles with the coal mining regions and subjects of interest. All references are annotated

  19. Operational Decision Support for Material Management in Continuous Mining Systems: From Simulation Concept to Practical Full-Scale Implementations

    Directory of Open Access Journals (Sweden)

    Masoud Soleymani Shishvan

    2017-07-01

    Full Text Available Material management in opencast mines is concerned with planning, organizing, and control of the flow of materials from their extraction points to destinations. It can be strongly affected by operational decisions that have to be made during the production process. To date, little research has focused on the application of simulation modeling as a powerful supportive tool for decision making in such systems. Practical experiences from implementing a simulation model of a mine for the operational support on an industrial scale are not known to the authors. This paper presents the extension of a developed stochastic simulation model by the authors from a conceptual stage (TRL4 to a new Technology Readiness Level (TRL 6 by implementing it in an industrially relevant environment. A framework for modeling, simulation, and validation of the simulation model applied to two large opencast lignite mines is presented in detail. Operational implementation issues, experiences, and challenges in practical applications are discussed. Furthermore, the strength of applying the simulation modeling as an operational decision support for material management in coal mining is demonstrated. Results of the case studies are used to describe the details of the framework, and to illustrate the strength and limitations of its application.

  20. Field Trial of Resin-Based Composite Materials for the Treatment of Surface Collapses Associated with Former Shallow Coal Mining

    OpenAIRE

    Philip T. Broughton; Mark P. Bettney; Isla L. Smail

    2016-01-01

    Effective treatment of ground instability is essential when managing the impacts associated with historic mining. A field trial was undertaken by the Coal Authority to investigate the geotechnical performance and potential use of composite materials comprising resin and fill or stone to safely treat surface collapses, such as crown-holes, associated with shallow mining. Test pits were loosely filled with various granular fill materials. The fill material was injected with commercially availab...

  1. Chemical properties and particle-size distribution of 39 surface-mine spoils in southern West Virginia

    Science.gov (United States)

    William T. Plass; Willis G. Vogel

    1973-01-01

    A survey of 39 surface-mine sites in southern West Virginia showed that most of the spoils from current mining operations had a pH of 5.0 or higher. Soil-size material averaged 37 percent of the weight of the spoils sampled. A major problem for the establishment of vegetation was a deficiency of nitrogen and phosphorus. This can be corrected with additions of...

  2. Changes in the Extent of Surface Mining and Reclamation in the Central Appalachians Detected Using a 1976-2006 Landsat Time Series

    Science.gov (United States)

    Townsend, Philip A.; Helmers, David P.; Kingdon, Clayton C.; McNeil, Brenden E.; de Beurs, Kirsten M.; Eshleman, Keith N.

    2009-01-01

    Surface mining and reclamation is the dominant driver of land cover land use change (LCLUC) in the Central Appalachian Mountain region of the Eastern U.S. Accurate quantification of the extent of mining activities is important for assessing how this LCLUC affects ecosystem services such as aesthetics, biodiversity, and mitigation of flooding.We used Landsat imagery from 1976, 1987, 1999 and 2006 to map the extent of surface mines and mine reclamation for eight large watersheds in the Central Appalachian region of West Virginia, Maryland and Pennsylvania. We employed standard image processing techniques in conjunction with a temporal decision tree and GIS maps of mine permits and wetlands to map active and reclaimed mines and track changes through time. For the entire study area, active surface mine extent was highest in 1976, prior to implementation of the Surface Mine Control and Reclamation Act in 1977, with 1.76% of the study area in active mines, declining to 0.44% in 2006. The most extensively mined watershed, Georges Creek in Maryland, was 5.45% active mines in 1976, declining to 1.83% in 2006. For the entire study area, the area of reclaimed mines increased from 1.35% to 4.99% from 1976 to 2006, and from 4.71% to 15.42% in Georges Creek. Land cover conversion to mines and then reclaimed mines after 1976 was almost exclusively from forest. Accuracy levels for mined and reclaimed cover was above 85% for all time periods, and was generally above 80% for mapping active and reclaimed mines separately, especially for the later time periods in which good accuracy assessment data were available. Among other implications, the mapped patterns of LCLUC are likely to significantly affect watershed hydrology, as mined and reclaimed areas have lower infiltration capacity and thus more rapid runoff than unmined forest watersheds, leading to greater potential for extreme flooding during heavy rainfall events.

  3. Thirteen-year hardwood tree performance on a Midwest surface mine

    International Nuclear Information System (INIS)

    Ashby, W.C.; Kolar, C.A.

    1998-01-01

    Black walnut (Juglans nigra L.), sweetgum (Liquidambar styraciflua L.), tuliptree (Liriodendron tulipifera L.), white oak (Quercus alba L.), bur oak (Q. macrocarpa Michx.), and pin oak (Q. palustris Muenchh.) seedlings were planted both fall 1980 and spring 1981 on mixed overburden strip-mining banks (ungraded), mixed overburden graded to approximate original contour (AOC) (graded), mixed overburden graded to AOC wit h 60 cm of replaced pre-mining surface soil materials (topsoil), and on old fields near the strip-mine (unmined). Black walnut and pin oak were also planted as seed, with a total of 6000 seedlings/seed spots in the study. Initial species field viability ranged from 86 to 100%. With one exception, after 3 growing seasons oak seedlings had 50% or greater survival. Survival was mostly lower after 3 years with some additional mortality by years 8 and 13. Height and diameter breast height were measured after 13 years. Survival and growth of trees planted fall or spring was similar overall with variable performance by species. Seedlings of several species on the ungraded site had over 50% survival after 13 years, with fewer trees where planted as seed. Mean height of all species combined was significantly greater on the ungraded than on any other site and was lowest on the topsoil site. The unmined sites had high variability in species survival and height. Better reclamation with trees resulted from a deep, well-drained rooting medium with minimal compaction and a mineral-rich surface soil including coarse fragments over 2 mm in size for long-term productivity

  4. Thirteen-year hardwood tree performance on a Midwest surface mine

    Energy Technology Data Exchange (ETDEWEB)

    Ashby, W.C.; Kolar, C.A. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Plant Biology

    1998-12-31

    Black walnut (Juglans nigra L.), sweetgum (Liquidambar styraciflua L.), tuliptree (Liriodendron tulipifera L.), white oak (Quercus alba L.), bur oak (Q. macrocarpa Michx.), and pin oak (Q. palustris Muenchh.) seedlings were planted both fall 1980 and spring 1981 on mixed overburden strip-mining banks (ungraded), mixed overburden graded to approximate original contour (AOC) (graded), mixed overburden graded to AOC wit h 60 cm of replaced pre-mining surface soil materials (topsoil), and on old fields near the strip-mine (unmined). Black walnut and pin oak were also planted as seed, with a total of 6000 seedlings/seed spots in the study. Initial species field viability ranged from 86 to 100%. With one exception, after 3 growing seasons oak seedlings had 50% or greater survival. Survival was mostly lower after 3 years with some additional mortality by years 8 and 13. Height and diameter breast height were measured after 13 years. Survival and growth of trees planted fall or spring was similar overall with variable performance by species. Seedlings of several species on the ungraded site had over 50% survival after 13 years, with fewer trees where planted as seed. Mean height of all species combined was significantly greater on the ungraded than on any other site and was lowest on the topsoil site. The unmined sites had high variability in species survival and height. Better reclamation with trees resulted from a deep, well-drained rooting medium with minimal compaction and a mineral-rich surface soil including coarse fragments over 2 mm in size for long-term productivity.

  5. Assessment of mercury erosion by surface water in Wanshan mercury mining area.

    Science.gov (United States)

    Dai, ZhiHui; Feng, Xinbin; Zhang, Chao; Shang, Lihai; Qiu, Guangle

    2013-08-01

    Soil erosion is a main cause of land degradation, and in its accelerated form is also one of the most serious ecological environmental problems. Moreover, there are few studies on migration of mercury (Hg) induced by soil erosion in seriously Hg-polluted districts. This paper selected Wanshan Hg mining area, SW China as the study area. Revised universal soil loss equation (RUSLE) and Geographic information system (GIS) methods were applied to calculate soil and Hg erosion and to classify soil erosion intensity. Our results show that the soil erosion rate can reach up to 600,884tkm(-2)yr(-1). Surfaces associated with very slight and extremely severe erosion include 76.6% of the entire land in Wanshan. Furthermore, the cumulative erosion rates in the area impacted by extremely severe erosion make up 90.5% of the total. On an annual basis, Hg surface erosion load was predicted to be 505kgyr(-1) and the corresponding mean migration flux of Hg was estimated to be 3.02kgkm(-2)yr(-1). The erosion loads of Hg resulting from farmland and meadow soil were 175 and 319kgyr(-1) respectively, which were enhanced compared to other landscape types due to the fact that they are generally located in the steep zones associated with significant reclamation. Contributing to establish a mass balance of Hg in Wanshan Hg mining area, this study supplies a dependable scientific basis for controlling soil and water erosion in the local ecosystems. Land use change is the most effective way for reducing Hg erosion load in Wanshan mining area. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. Mining soil phosphorus by zero P-application: an effective method to reduce the risk of P loading to surface water

    NARCIS (Netherlands)

    Salm, van der C.; Chardon, W.J.; Koopmans, G.F.

    2007-01-01

    This study aims to find field evidence for the effectiveness of P-mining to reduce the risk of P leaching to surface water. In 2002, a P-mining was conducted on four grassland sites in the Netherlands on sand (two sites), peat and clay soils. The mining plots received no P and an annual N surplus of

  7. Local community opinions regarding the socio-environmental aspects of lignite surface mining: Experiences from central Poland

    International Nuclear Information System (INIS)

    Badera, Jarosław; Kocoń, Paweł

    2014-01-01

    Surface lignite mining covers large areas and usually generates social conflicts which pose one of several energy security threats to certain states. Therefore, defining the social conditions determines the success of a mining project. Two communes were chosen for a public opinion study: Kleszczów, where the Bełchatów mine is located, and Złoczew, where a lignite deposit will soon be developed. The analysis shows, as opposed to other areas in Poland that have been projected for development, that both local communities are characterised by a high level of acceptance for lignite mining. In both cases, awareness about the profits was stronger than anxiety about the investment's negative effects. However, most inhabitants could not assess the mining company's diligence concerning its responsibility for mining damages as well as the diligence of external experts assessing the environmental impacts of excavation. Most respondents also could not assess if the legal regulations of public participation in the decision process were sufficient, but the negative opinions outweighed the positive ones. From the perspective of the energy policy, dialogue-type social communication is needed for every case of a new energy-mining project. Research on local public opinion should be the first step to opening up a social debate. - Highlights: • Lignite mining can generate social conflicts, which may threaten energy security. • Examined communes are characterised by a high level of acceptance for lignite mining. • Inhabitants cannot assess if the legal regulations of mining activity are sufficient. • From the perspective of the energy policy, broader social communication is needed. • Research on the public opinion should be the first step to open up a social debate

  8. Debilitating lung disease among surface coal miners with no underground mining tenure.

    Science.gov (United States)

    Halldin, Cara N; Reed, William R; Joy, Gerald J; Colinet, Jay F; Rider, James P; Petsonk, Edward L; Abraham, Jerrold L; Wolfe, Anita L; Storey, Eileen; Laney, A Scott

    2015-01-01

    To characterize exposure histories and respiratory disease among surface coal miners identified with progressive massive fibrosis from a 2010 to 2011 pneumoconiosis survey. Job history, tenure, and radiograph interpretations were verified. Previous radiographs were reviewed when available. Telephone follow-up sought additional work and medical history information. Among eight miners who worked as drill operators or blasters for most of their tenure (median, 35.5 years), two reported poor dust control practices, working in visible dust clouds as recently as 2012. Chest radiographs progressed to progressive massive fibrosis in as few as 11 years. One miner's lung biopsy demonstrated fibrosis and interstitial accumulation of macrophages containing abundant silica, aluminum silicate, and titanium dust particles. Overexposure to respirable silica resulted in progressive massive fibrosis among current surface coal miners with no underground mining tenure. Inadequate dust control during drilling/blasting is likely an important etiologic factor.

  9. The Influence of Surface Coal Mining on Runoff Processes and Stream Chemistry in the Elk Valley, British Colubmbia, Canada

    Science.gov (United States)

    Carey, S. K.; Wellen, C. C.; Shatilla, N. J.

    2015-12-01

    Surface mining is a common method of accessing coal. In high-elevation environments, vegetation and soils are typically removed prior to the blasting of overburden rock, thereby allowing access to mineable ore. Following this, the removed overburden rock is deposited in adjacent valleys as waste rock spoils. Previous research has identified that areas downstream of surface coal mining have impaired water quality, yet there is limited information about the interaction of hydrology and geochemistry across a range of mining conditions, particularly at the headwater scale. Here, we provide an analysis of an extensive long-term data set of geochemistry and flows across a gradient of coal mining in the Elk Valley, British Columbia, Canada. This work is part of a broader R&D program examining the influence of surface coal mining on hydrological and water quality responses in the Elk Valley aimed at informing effective management responses. Results indicate that water from waste rock piles has an ionic profile distinct from unimpacted catchments. While the concentration of geochemicals increased with the degree of mine impact, the control of hydrological transport capacity over geochemical export did not vary with degree of mine impact. Geochemical export in mine-influenced catchments was limited more strongly by transport capacity than supply, implying that more water moving through the waste rock mobilized more geochemicals. Placement of waste rock within the catchment (headwaters or outlet) did not affect chemical concentrations but did alter the timing with which chemically distinct water mixed. This work advances on results reported earlier using empirical models of selenium loading and further highlights the importance of limiting water inputs into waste rock piles.

  10. Analysis of Maintenance Service Contracts for Dump Trucks Used in Mining Industry with Simulation Approach

    Science.gov (United States)

    Dymasius, A.; Wangsaputra, R.; Iskandar, B. P.

    2016-02-01

    A mining company needs high availability of dump trucks used to haul mining materials. As a result, an effective maintenance action is required to keep the dump trucks in a good condition and hence reducing failure and downtime of the dump trucks. To carry out maintenance in-house requires a high intensive maintenance facility and high skilled maintenance specialists. Often, outsourcing maintenance is an economic option for the company. An external agent takes a proactive action with offering some maintenance contract options to the owner. The decision problem for the owner is to decide the best option and for the agent is to determine the optimal price for each option offered. A non-cooperative game-theory is used to formulate the decision problems for the owner and the agent. We consider that failure pattern of each truck follows a non-homogeneous Poisson process (NHPP) and a queueing theory with multiple servers is used to estimate the downtime. As it involves high complexity to model downtime using a queueing theory, then in this paper we use a simulation method. Furthermore, we conduct experiment to seek for the best number of maintenance facilities (servers) which minimises maintenance and penalty costs incurred to the agent.

  11. Simulating the hydrologic cycle in coal mining subsidence areas with a distributed hydrologic model.

    Science.gov (United States)

    Wang, Jianhua; Lu, Chuiyu; Sun, Qingyan; Xiao, Weihua; Cao, Guoliang; Li, Hui; Yan, Lingjia; Zhang, Bo

    2017-01-20

    Large-scale ground subsidence caused by coal mining and subsequent water-filling leads to serious environmental problems and economic losses, especially in plains with a high phreatic water level. Clarifying the hydrologic cycle in subsidence areas has important practical value for environmental remediation, and provides a scientific basis for water resource development and utilisation of the subsidence areas. Here we present a simulation approach to describe interactions between subsidence area water (SW) and several hydrologic factors from the River-Subsidence-Groundwater Model (RSGM), which is developed based on the distributed hydrologic model. Analysis of water balance shows that the recharge of SW from groundwater only accounts for a small fraction of the total water source, due to weak groundwater flow in the plain. The interaction between SW and groundwater has an obvious annual cycle. The SW basically performs as a net source of groundwater in the wet season, and a net sink for groundwater in the dry season. The results show there is an average 905.34 million m 3 per year of water available through the Huainan coal mining subsidence areas (HCMSs). If these subsidence areas can be integrated into water resource planning, the increasingly precarious water supply infrastructure will be strengthened.

  12. July 2011 Memorandum: Improving EPA Review of Appalachian Surface Coal Mining Operations Under the Clean Water Act, National Environmental Policy Act, and the Environmental Justice Executive Order

    Science.gov (United States)

    Memorandum: Improving EPA Review of Appalachian Surface Coal Mining Operations Under the Clean Water Act, National Environmental Policy Act, and the Environmental Justice Executive Order, July 21, 2011

  13. Local grid refinement for free-surface flow simulations

    NARCIS (Netherlands)

    van der Plas, Peter

    2017-01-01

    The principal goal of the current study is to explore and investigate the potential of local grid refinement for increasing the numerical efficiency of free-surface flow simulations in a practical context. In this thesis we propose a method for local grid refinement in the free-surface flow model

  14. Vertical Displacement of the Surface Area over the Leakage to the Transverse salt Mine in 1992-2012

    Science.gov (United States)

    Lipecki, Tomasz

    2018-03-01

    The leakage of water in the salt mine caused considerable deformation of the surface. This article shows the vertical displacement in the area of leakage to the mine excavation, measured by precision leveling, carried out from the first days of leakage in 1992 until 2012. The geological and hydrogeological conditions of the mine, as well as the associated water hazards were described, which in conjunction with the inconvenient location of the excavation site in the northern frontage of the Carpathians and also inadequately conducted mining operations, contributed to the risk of flooding mine. The analysis of the vertical movements of the surface - subsidence and uplift - were present as well as the process of formation of the depression trough in the form of maps and graphs. The analyzes were based on 49 measurement series, starting from the first days of the disaster within the next 20 years. The course of development of the depression trough and the condition of the surface after stopping the water from the rock mass has been shown, which caused the surface to uplift.

  15. Simulation of Solar Radiation Incident on Horizontal and Inclined Surfaces

    Directory of Open Access Journals (Sweden)

    MA Basunia

    2012-12-01

    Full Text Available A computer model was developed to simulate the hourly, daily and monthly average of daily solar radiation on horizontal and inclined surfaces. The measured hourly and daily solar radiation was compared with simulated radiation, and favourable agreement was observed for the measured and predicted values on clear days. The measured and simulated monthly averages of total (diffuse and beam daily solar radiation were compared and a reasonable agreement was observed for a number of stations in Japan. The simulation showed that during the rice harvesting season, September to October, there is a daily average of 14.7 MJ/m2 of solar irradiation on a horizontal surface in Matsuyama, Japan. There is a similar amount of solar radiation on a horizontal surface during the major rice harvesting season, November to December, in Bangladesh. This radiation can be effectively utilized for drying rough rice and other farm crops.

  16. Mining for diagnostic information in body surface potential maps: A comparison of feature selection techniques

    Directory of Open Access Journals (Sweden)

    McCullagh Paul J

    2005-09-01

    Full Text Available Abstract Background In body surface potential mapping, increased spatial sampling is used to allow more accurate detection of a cardiac abnormality. Although diagnostically superior to more conventional electrocardiographic techniques, the perceived complexity of the Body Surface Potential Map (BSPM acquisition process has prohibited its acceptance in clinical practice. For this reason there is an interest in striking a compromise between the minimum number of electrocardiographic recording sites required to sample the maximum electrocardiographic information. Methods In the current study, several techniques widely used in the domains of data mining and knowledge discovery have been employed to mine for diagnostic information in 192 lead BSPMs. In particular, the Single Variable Classifier (SVC based filter and Sequential Forward Selection (SFS based wrapper approaches to feature selection have been implemented and evaluated. Using a set of recordings from 116 subjects, the diagnostic ability of subsets of 3, 6, 9, 12, 24 and 32 electrocardiographic recording sites have been evaluated based on their ability to correctly asses the presence or absence of Myocardial Infarction (MI. Results It was observed that the wrapper approach, using sequential forward selection and a 5 nearest neighbour classifier, was capable of choosing a set of 24 recording sites that could correctly classify 82.8% of BSPMs. Although the filter method performed slightly less favourably, the performance was comparable with a classification accuracy of 79.3%. In addition, experiments were conducted to show how (a features chosen using the wrapper approach were specific to the classifier used in the selection model, and (b lead subsets chosen were not necessarily unique. Conclusion It was concluded that both the filter and wrapper approaches adopted were suitable for guiding the choice of recording sites useful for determining the presence of MI. It should be noted however

  17. Utilization of textile surface covers for stabilizing slopes in brown coal surface mines

    Energy Technology Data Exchange (ETDEWEB)

    Rathmann, K.; Ganz, R.; Taubert, E.; Scheler, D.

    1980-01-01

    Results are presented of tests on preventing slope erosion at a spoil bank by covering inclined surfaces with textile. Three polyethylene and one polyamide cloth types with varying mesh size and material elasticity were attached to the ground after seeding of grass plants. Slope erosion and grass growth were evaluated at three-week intervals. Best results were achieved with polyethylene cloth with a 10/20 mm mesh to facilitate grass growth and with low elasticity, which showed the best adaption to the slope of the ground and prevented washout from below. Economic advantages of using surface covers are described as reducing expenditures in labor employed in slope maintenance. A 50% cost saving is estimated, which depends on the availability of low cost ground covers, preferably from waste products. The suitability of textile from magnetic tape scrap will be tested.

  18. Water resources and effects of potential surface coal mining on dissolved solids in Hanging Woman Creek basin, southeastern Montana

    Science.gov (United States)

    Cannon, M.R.

    1989-01-01

    Groundwater resources of the Hanging Woman Creek basin, Montana include Holocene and Pleistocene alluvial aquifers and sandstone , coal, and clinker aquifers in the Paleocene Fort Union Formation. Surface water resources are composed of Hanging Woman Creek, its tributaries, and small stock ponds. Dissolved-solids concentrations in groundwater ranged from 200 to 11,00 mg/L. Generally, concentrations were largest in alluvial aquifers and smallest in clinker aquifers. Near its mouth, Hanging Woman Creek had a median concentration of about 1,800 mg/L. Mining of the 20-foot to 35-foot-thick Anderson coal bed and 3-foot to 16-foot thick Dietz coal bed could increase dissolved-solids concentrations in shallow aquifers and in Hanging Woman Creek because of leaching of soluble minerals from mine spoils. Analysis of saturated-paste extracts from 158 overburden samples indicated that water moving through mine spoils would have a median increase in dissolved-solids concentration of about 3,700 mg/L, resulting in an additional dissolved-solids load to Hanging Woman Creek of about 3.0 tons/day. Hanging Woman Creek near Birney could have an annual post-mining dissolved-solids load of 3,415 tons at median discharge, a 47% increase from pre-mining conditions load. Post-mining concentrations of dissolved solids, at median discharge, could range from 2,380 mg/L in March to 3,940 mg/L in August, compared to mean pre-mining concentrations that ranged from 1,700 mg/L in July, November, and December to 2,060 mg/L in May. Post-mining concentrations and loads in Hanging Woman Creek would be smaller if a smaller area were mined. (USGS)

  19. Role of soil health in maintaining environmental sustainability of surface coal mining.

    Science.gov (United States)

    Acton, Peter M; Fox, James F; Campbell, J Elliott; Jones, Alice L; Rowe, Harold; Martin, Darren; Bryson, Sebastian

    2011-12-01

    Mountaintop coal mining (MCM) in the Southern Appalachian forest region greatly impacts both soil and aquatic ecosystems. Policy and practice currently in place emphasize water quality and soil stability but do not consider upland soil health. Here we report soil organic carbon (SOC) measurements and other soil quality indicators for reclaimed soils in the Southern Appalachian forest region to quantify the health of the soil ecosystem. The SOC sequestration rate of the MCM soils was 1.3 MgC ha(-1) yr(-1) and stocks ranged from 1.3 ± 0.9 to 20.9 ± 5.9 Mg ha(-1) and contained only 11% of the SOC of surrounding forest soils. Comparable reclaimed mining soils reported in the literature that are supportive of soil ecosystem health had SOC stocks 2.5-5 times greater than the MCM soils and sequestration rates were also 1.6-3 times greater. The high compaction associated with reclamation in this region greatly reduces both the vegetative rooting depth and infiltration of the soil and increases surface runoff, thus bypassing the ability of soil to naturally filter groundwater. In the context of environmental sustainability of MCM, it is proposed that the entire watershed ecosystem be assessed and that a revision of current policy be conducted to reflect the health of both water and soil.

  20. Measurement of sub-surface strata behaviour in bord and pillar mining: a case study

    International Nuclear Information System (INIS)

    Krishna, R.

    1991-01-01

    Ranigunj coalfield (India) has been facing significant problems due to subsidence as a result of underground mining of coal seams. The occurrence of the thick seams in close proximity, shallow depth, great variation in the nature of superincumbent strata from site to site, followed by the slow rate of extraction, has aggravated subsidence problems. In the recent past, many such workings have collapsed, damaging a large number of surface structures. In view of the aforesaid need, a comprehensive project financed by the Ministry of Energy (Coal), was undertaken by the Department of Mining Engineering, Indian Institute of Technology, Kharagpur, at a Colliery in Ranigunj Coalfield. This investigation revealed that the caving horizon occurred at 4 times the extracted seam height, which differs from the findings in the UK, USA, and Australia. Also, it appears possible to estimate strata displacements from geological and physicomechanical information from the overlying rocks using the bending moment principle. Further, it was observed that the shallow workings could give rise to a sink hole type of subsidence, which is dangerous and could adversely affect the environment, safety of the public and properties. 11 refs., 13 figs., 1 tab

  1. Mathematic simulation of mining company’s power demand forecast (by example of “Neryungri” coal strip mine)

    Science.gov (United States)

    Antonenkov, D. V.; Solovev, D. B.

    2017-10-01

    The article covers the aspects of forecasting and consideration of the wholesale market environment in generating the power demand forecast. Major mining companies that operate in conditions of the present day power market have to provide a reliable energy demand request for a certain time period ahead, thus ensuring sufficient reduction of financial losses associated with deviations of the actual power demand from the expected figures. Normally, under the power supply agreement, the consumer is bound to provide a per-month and per-hour request annually. It means that the consumer has to generate one-month-ahead short-term and medium-term hourly forecasts. The authors discovered that empiric distributions of “Yakutugol”, Holding Joint Stock Company, power demand belong to the sustainable rank parameter H-distribution type used for generating forecasts based on extrapolation of such distribution parameters. For this reason they justify the need to apply the mathematic rank analysis in short-term forecasting of the contracted power demand of “Neryungri” coil strip mine being a component of the technocenosis-type system of the mining company “Yakutugol”, Holding JSC.

  2. Surface Soil Preparetion for Leguminous Plants Growing in Degraded Areas by Mining Located in Amazon Forest-Brazil

    Science.gov (United States)

    Irio Ribeiro, Admilson; Hashimoto Fengler, Felipe; Araújo de Medeiros, Gerson; Márcia Longo, Regina; Frederici de Mello, Giovanna; José de Melo, Wanderley

    2015-04-01

    The revegetation of areas degraded by mining usually requires adequate mobilization of surface soil for the development of the species to be implemented. Unlike the traditional tillage, which has periodicity, the mobilization of degraded areas for revegetation can only occur at the beginning of the recovery stage. In this sense, the process of revegetation has as purpose the establishment of local native vegetation with least possible use of inputs and superficial tillage in order to catalyze the process of natural ecological succession, promoting the reintegration of areas and minimizing the negative impacts of mining activities in environmental. In this context, this work describes part of a study of land reclamation by tin exploitation in the Amazon ecosystem in the National Forest Jamari- Rondonia Brazil. So, studied the influence of surface soil mobilization in pit mine areas and tailings a view to the implementation of legumes. The results show that the surface has areas of mobilizing a significant effect on the growth of leguminous plants, areas for both mining and to tailings and pit mine areas.

  3. Simple model of surface roughness for binary collision sputtering simulations

    International Nuclear Information System (INIS)

    Lindsey, Sloan J.; Hobler, Gerhard; Maciążek, Dawid; Postawa, Zbigniew

    2017-01-01

    Highlights: • A simple model of surface roughness is proposed. • Its key feature is a linearly varying target density at the surface. • The model can be used in 1D/2D/3D Monte Carlo binary collision simulations. • The model fits well experimental glancing incidence sputtering yield data. - Abstract: It has been shown that surface roughness can strongly influence the sputtering yield – especially at glancing incidence angles where the inclusion of surface roughness leads to an increase in sputtering yields. In this work, we propose a simple one-parameter model (the “density gradient model”) which imitates surface roughness effects. In the model, the target’s atomic density is assumed to vary linearly between the actual material density and zero. The layer width is the sole model parameter. The model has been implemented in the binary collision simulator IMSIL and has been evaluated against various geometric surface models for 5 keV Ga ions impinging an amorphous Si target. To aid the construction of a realistic rough surface topography, we have performed MD simulations of sequential 5 keV Ga impacts on an initially crystalline Si target. We show that our new model effectively reproduces the sputtering yield, with only minor variations in the energy and angular distributions of sputtered particles. The success of the density gradient model is attributed to a reduction of the reflection coefficient – leading to increased sputtering yields, similar in effect to surface roughness.

  4. Coal Mine Permit Boundaries

    Data.gov (United States)

    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...

  5. Abandoned Uranium Mine (AUM) Surface Areas, Navajo Nation, 2016, US EPA Region 9

    Data.gov (United States)

    U.S. Environmental Protection Agency — This GIS dataset contains polygon features that represent all Abandoned Uranium Mines (AUMs) on or within one mile of the Navajo Nation. Attributes include mine...

  6. Molecular dynamics simulation of annealed ZnO surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Min, Tjun Kit; Yoon, Tiem Leong [School of Physics, Universiti Sains Malaysia, 11800 USM, Penang (Malaysia); Lim, Thong Leng [Faculty of Engineering and Technology, Multimedia University, Melaka Campus, 75450 Melaka (Malaysia)

    2015-04-24

    The effect of thermally annealing a slab of wurtzite ZnO, terminated by two surfaces, (0001) (which is oxygen-terminated) and (0001{sup ¯}) (which is Zn-terminated), is investigated via molecular dynamics simulation by using reactive force field (ReaxFF). We found that upon heating beyond a threshold temperature of ∼700 K, surface oxygen atoms begin to sublimate from the (0001) surface. The ratio of oxygen leaving the surface at a given temperature increases as the heating temperature increases. A range of phenomena occurring at the atomic level on the (0001) surface has also been explored, such as formation of oxygen dimers on the surface and evolution of partial charge distribution in the slab during the annealing process. It was found that the partial charge distribution as a function of the depth from the surface undergoes a qualitative change when the annealing temperature is above the threshold temperature.

  7. Superhydrophobic surfaces: From nature to biomimetic through VOF simulation.

    Science.gov (United States)

    Liu, Chunbao; Zhu, Ling; Bu, Weiyang; Liang, Yunhong

    2018-04-01

    The contact angle, surface structure and chemical compositions of Canna leaves were investigated. According to the surface structure of Canna leaves which observed by Scanning Electron Microscopy(SEM), the CFD (Computational Fluid Dynamics)model was established and the method of volume of fluid (VOF) was used to simulate the process of droplet impacting on the surface and established a smooth surface for comparison to verify that the surface structure was an important factor of the superhydrophobic properties. Based on the study of Canna leaf and VOF simulation of its surface structure, the superhydrophobic samples were processed successfully and showed a good superhydrophobic property with a contact angle of 156 ± 1 degrees. A high-speed camera (5000 frames per second) was used to assess droplet movement and determine the contact time of the samples. The contact time for the sample was 13.1 ms. The results displayed that the artificial superhydrophobic surface is perfect for the performance of superhydrophobic properties. The VOF simulation method was efficient, accurate and low cost before machining artificial superhydrophobic samples. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. Distributions and concentrations of thallium in surface waters of a region impacted by historical metal mining (Cornwall, UK).

    Science.gov (United States)

    Tatsi, Kristi; Turner, Andrew

    2014-03-01

    Thallium is a highly toxic heavy metal whose concentrations and distributions in the aquatic environment are poorly defined. In this study, concentrations of aqueous and total Tl have been measured in water samples from a variety of rivers and effluents (the latter related to historical metal mining) in the county of Cornwall, SW England. Aqueous concentrations ranged from about 13 ng L(-1) in a river whose catchment contained no metal mines to 2,640 ng L(-1) in water abstracted directly from an abandoned mine shaft. Concentrations of Tl in rivers were greatest in the vicinity of mine-related effluents, with a maximum value measured of about 770 ng L(-1). Thallium was not efficiently removed by the conventional, active treatment of mine water, and displayed little interaction with suspended particles. Its mobility in surface waters, coupled with concentrations that are close to a quality guideline of 800 ng L(-1), is cause for concern. Accordingly, we recommend that the metal is more closely monitored in this and other regions impacted by mining activities. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Radiological assessment of surface water quality around proposed uranium mining site in India.

    Science.gov (United States)

    Jha, S K; Lenka, P; Gothankar, S; Tripathi, R M; Puranik, V D; Khating, D T

    2009-06-01

    The gross alpha and gross beta activities were estimated for radiological assessment of surface water quality around the proposed uranium mining site Kylleng Pyndengsohiong Mawthabah (Domiasiat), West Khasi Hills District, Meghalaya situated in a high rainfall area (12,000mm) in India. 189 Surface water samples were collected over different seasons of the year from nine different locations covering around 100km(2). Gross beta activities were found to vary from 144 to 361mBq/L which is much below the prescribed WHO limit of 1000mBq/L for drinking water. Gross alpha activities varied from 61 to 127mBq/L. These values are much below the reported gross alpha values by other countries. In about 7% of the samples the alpha activities remain exceeded the WHO guideline limit of 100mBq/L. Surface water samples collected during the summer season of the year show higher activity whereas low activity was found from samples collected during monsoon season. Results show that all water sources are acceptable as drinking water for human consumption from the radiological point of view, the higher gross alpha concentrations in a few locations remains so only for short duration during the summer season.

  10. Radiological assessment of surface water quality around proposed uranium mining site in India

    International Nuclear Information System (INIS)

    Jha, S.K.; Lenka, P.; Gothankar, S.; Tripathi, R.M.; Puranik, V.D.; Khating, D.T.

    2009-01-01

    The gross alpha and gross beta activities were estimated for radiological assessment of surface water quality around the proposed uranium mining site Kylleng Pyndengsohiong Mawthabah (Domiasiat), West Khasi Hills District, Meghalaya situated in a high rainfall area (12,000 mm) in India. 189 Surface water samples were collected over different seasons of the year from nine different locations covering around 100 km 2 . Gross beta activities were found to vary from 144 to 361 mBq/L which is much below the prescribed WHO limit of 1000 mBq/L for drinking water. Gross alpha activities varied from 61 to 127 mBq/L. These values are much below the reported gross alpha values by other countries. In about 7% of the samples the alpha activities remain exceeded the WHO guideline limit of 100 mBq/L. Surface water samples collected during the summer season of the year show higher activity whereas low activity was found from samples collected during monsoon season. Results show that all water sources are acceptable as drinking water for human consumption from the radiological point of view, the higher gross alpha concentrations in a few locations remains so only for short duration during the summer season.

  11. Microprocessor-based simulator of surface ECG signals

    International Nuclear Information System (INIS)

    MartInez, A E; Rossi, E; Siri, L Nicola

    2007-01-01

    In this work, a simulator of surface electrocardiogram recorded signals (ECG) is presented. The device, based on a microcontroller and commanded by a personal computer, produces an analog signal resembling actual ECGs, not only in time course and voltage levels, but also in source impedance. The simulator is a useful tool for electrocardiograph calibration and monitoring, to incorporate as well in educational tasks and in clinical environments for early detection of faulty behaviour

  12. Multiscale simulation of ion beam impacts on a graphene surface

    International Nuclear Information System (INIS)

    Dybyspayeva, K B; Zhuldassov, A; Ainabayev, A; Insepov, Z; Vyatkin, A F; Alekseev, K

    2016-01-01

    Multiscale study of single and multilayer graphene irradiation is presented in this paper. Ab-initio density-functional theory (DFT) was used to study point defects, and a large scale parallel molecular-dynamics (MD) simulations were used for studying formation of gas cluster ion impacts. Moreover, Raman spectra of pure and defect graphene samples were studied from DFT calculations. Threshold energies for creating craters on the surface of graphene were obtained from MD and compared with published papers. The results of simulations were also compared with experimental craters and surface shape. (paper)

  13. Numerical simulations of viscoelastic flows with free surfaces

    DEFF Research Database (Denmark)

    Comminal, Raphaël; Spangenberg, Jon; Hattel, Jesper Henri

    2013-01-01

    We present a new methodology to simulate viscoelastic flows with free-surfaces. These simulations are motivated by the modelling of polymers manufacturing techniques, such as extrusion and injection moulding. One of the consequences of viscoelasticity is that polymeric materials have a “memory......” of their past deformations. This generates some numerical difficulties which are addressed with the log-conformation transformation. The main novelty of this work lies on the use of the volume-of-fluid method to track the free surfaces of the viscoelastic flows. We present some preliminary results of test case...

  14. Selective bibliography of surface coal mining and reclamation literature. Volume 1. Eastern coal province. [More than 1300 references

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, N. E.; Sobek, A. A.; Streib, D. L.

    1977-11-01

    This bibliography has been compiled for use by researchers, students, and other groups who need a reference source of published literature related to surface coal mining and reclamation in the Eastern Coal Province. This bibliography contains more than 1300 references including government reports, journal articles, symposium proceedings, industrial reports, workshop proceedings, theses, and bibliographices. A simple format was used to categorize citations.

  15. Nesting success of grassland and savanna birds on reclaimed surface coal mines of the midwestern United States

    Energy Technology Data Exchange (ETDEWEB)

    Galligan, E.W.; DeVault, T.L.; Lima, S.L. [Indiana State University, Terre Haute, IN (United States)

    2006-12-15

    Reclaimed surface coal mines in southwestern Indiana support many grassland and shrub/savanna bird species of conservation concern. We examined the nesting success of birds on these reclaimed mines to assess whether such 'unnatural' places represent productive breeding habitats for such species. We established eight study sites on two large, grassland-dominated mines in southwestern Indiana and classified them into three categories (open grassland, shrub/savanna, and a mixture of grassland and shrub/savanna) based on broad vegetation and landscape characteristics. During the 1999 and 2000 breeding seasons, we found and monitored 911 nests of 31 species. Daily nest survival for the most commonly monitored grassland species ranged from 0.903 (Dickcissel, Spiza americana) to 0.961 (Grasshopper Sparrow, Ammodramus savannarum). Daily survival estimates for the dominant shrub/savanna nesting species ranged from 0.932 (Brown Thrasher, Toxostoma rufum) to 0.982 (Willow Flycatcher, Empidonax traillii). Vegetation and landscape effects on nesting success were minimal, and only Eastern Meadowlarks (Sturnella magna) showed a clear time-of-season effect, with greater nesting success in the first half of the breeding season. Rates of Brown-headed Cowbird (Molothrus ater) parasitism were only 2.1% for grassland species and 12.0% for shrub/savanna species. The nesting success of birds on reclaimed mine sites was comparable to that in other habitats, indicating that reclaimed habitats on surface mines do not necessarily represent reproductive traps for birds.

  16. Simulation of Langmuir-Blodgett film surface STM images

    International Nuclear Information System (INIS)

    Agabekov, V.E.; Zhavnerko, G.K.; Bar, G.; Cantov, H.J.

    1998-01-01

    The simulation of the STM image of a hydrocarbon tail of the fatty acid was carried out and compared to the experimental results. The simulation procedure includes calculations of the distribution of an isolated molecule electronic density by the extended Huckel-Hoffman method. An agreement between the calculated and experimental STM images of closely packed Langmuir-Blodgett film of cobalt behenate on the graphite surface and the adsorbed molecules constituting bi- and multilayer Langmuir-Blodgett films can be neglected in simulations of STM images. (author)

  17. Simulation of secondary electron emission from rough surfaces

    International Nuclear Information System (INIS)

    Kawata, J.; Ohya, K.; Nishimura, K.

    1995-01-01

    The effect of surface roughness on the secondary electron emission from a beryllium surface under low-energy (≤1 keV) electron bombardment is investigated using a Monte Carlo simulation combined with the model of bowl-structured surface. With increasing aspect ratio H/W of the bowl structure, the secondary electron yield becomes greater than that for a flat surface, whereas for large H/W the yield is smaller; where H and W are the depth and width of the bowl structure, respectively. The former is due to emission of electrons, which cannot escape from the flat surface, from an inclined plane; it increases the low-energy component in the energy distribution. The latter is due to re-entrance of once-emitted electrons into the next part of the topographic surface; it decreases the number of electrons emitted with oblique angles. ((orig.))

  18. Simulations of surface stress effects in nanoscale single crystals

    Science.gov (United States)

    Zadin, V.; Veske, M.; Vigonski, S.; Jansson, V.; Muszinsky, J.; Parviainen, S.; Aabloo, A.; Djurabekova, F.

    2018-04-01

    Onset of vacuum arcing near a metal surface is often associated with nanoscale asperities, which may dynamically appear due to different processes ongoing in the surface and subsurface layers in the presence of high electric fields. Thermally activated processes, as well as plastic deformation caused by tensile stress due to an applied electric field, are usually not accessible by atomistic simulations because of the long time needed for these processes to occur. On the other hand, finite element methods, able to describe the process of plastic deformations in materials at realistic stresses, do not include surface properties. The latter are particularly important for the problems where the surface plays crucial role in the studied process, as for instance, in the case of plastic deformations at a nanovoid. In the current study by means of molecular dynamics (MD) and finite element simulations we analyse the stress distribution in single crystal copper containing a nanovoid buried deep under the surface. We have developed a methodology to incorporate the surface effects into the solid mechanics framework by utilizing elastic properties of crystals, pre-calculated using MD simulations. The method leads to computationally efficient stress calculations and can be easily implemented in commercially available finite element software, making it an attractive analysis tool.

  19. Development of near surface seismic methods for urban and mining applications

    Science.gov (United States)

    Malehmir, Alireza; Brodic, Bojan; Place, Joachim; Juhlin, Christopher; Bastani, Mehrdad

    2014-05-01

    There is a great need to improve our understanding of the geological conditions in the shallow subsurface. Direct observations of the subsurface are cumbersome and expensive, and sometimes impossible. Urban and mining areas are especially challenging due to various sources of noise such as from traffic, buildings, cars, city trains, trams, bridges and high-voltage power-lines. Access is also restricted both in time and space, which requires the equipment to be versatile, fast to set up and pack, and produces the least disruptions. However, if properly designed and implemented, geophysical methods are capable of imaging detailed subsurface structures and can successfully be used to provide crucial information for site characterizations, infrastructure planning, brown- and near-field exploration, and mine planning. To address some of these issues Uppsala University, in collaboration with a number of public authorities, research organizations and industry partners, has recently developed a prototype broadband (0-800 Hz based on digital sensors) multi-component seismic landstreamer system. The current configuration consists of three segments with twenty 3C-sensors each 2 m apart and an additional segment with twenty 3C-sensors each 4 m apart, giving a total streamer length of 200 m. These four segments can be towed in parallel or in series, which in combination with synchronized wireless and cabled sensors can address a variety of complex near surface problems. The system is especially geared for noisy environments and areas where high-resolution images of the subsurface are needed. The system has little sensitivity to electrical noise and measures sensor tilt, important in rough terrains, so it can immediately be corrected for during the acquisition. Thanks to the digital sensors, the system can also be used for waveform tomography and multi-channel analysis of surface waves (MASW). Both these methods require low frequencies and these are often sacrificed in

  20. Derived limits for occupational exposure to uranium mine and mill dusts in the air and on surfaces

    International Nuclear Information System (INIS)

    Carter, M.W.

    1983-01-01

    Limits are derived for the concentration of uranium mine and mill dusts in the air based on ICRP30 and assumptions regarding the isotopic make up of the dusts. From these limits using a resuspension factor, limits for surface contamination are derived. Calculations are presented of the dose to the basal layer of the skin from mine and mill dusts on the skin. From these calculations limits for skin contamination are derived. A calculation of a limit based on direct ingestion is also presented. Exposure limits for the public are not considered

  1. Moving least squares simulation of free surface flows

    DEFF Research Database (Denmark)

    Felter, C. L.; Walther, Jens Honore; Henriksen, Christian

    2014-01-01

    In this paper a Moving Least Squares method (MLS) for the simulation of 2D free surface flows is presented. The emphasis is on the governing equations, the boundary conditions, and the numerical implementation. The compressible viscous isothermal Navier–Stokes equations are taken as the starting ...

  2. Astronaut Neil Armstrong participates in lunar surface simulation training

    Science.gov (United States)

    1969-01-01

    Astronaut Neil A. Armstrong, wearing an Extravehicular Mobility Unit (EMU), participates in lunar surface simulation training on April 18, 1969 in bldg 9, Manned Spacecraft Center. Armstrong is the prime crew commander of the Apollo 11 lunar landing mission. Here, he is standing on Lunar Module mockup foot pad preparing to ascend steps.

  3. Simulation of long-term erosion on an abandoned mine site using the SIBERIA landscape evolution model

    International Nuclear Information System (INIS)

    Hancock, G.; Willgoose, G.; Evans, K.

    1999-01-01

    The SIBERIA catchment evolution model can simulate the evolution of landforms over many years as a result of runoff and erosion. This study discusses testing of the reliability of the erosion predictions of the model in a field study. Using erosion parameters calibrated from field studies of rainfall and runoff from the waste rock dump batters, the SIBERIA landscape evolution model was calibrated and then used to simulate erosion over 50 years on the abandoned Scinto 6 mine site. Scinto 6 is a former uranium mine located in the Kakadu Region, Northern Territory, Australia. The SIBERIA runs simulated the geomorphic development of the gullies on the man-made batters of the waste rock dump. The waste rock of the mine had been dumped in the characteristic pattern of a flat top and steep sided batters typical of many former and current dumps and there had been significant degradation from both sheet and gully erosion. Traditional erosion models cannot model this type of degradation because their erosion model cannot change the landform, while SIBERIA does change the landform. The gully position, depth volume and morphology on the waste rock dump were compared with that of SIBERIA simulations. The geomorphic development of the waste rock dump indicated that SIBERIA can simulate features that arise from the long-term effect of erosion and also their rate of development on a man-made post-mining landscape over periods of up to 50 years. The detailed results of this specific study will be discussed with specific discussion of the type of data required and the implications of the uncertain erosion physics on the reliability of the predictions

  4. Modeling and Simulation of the Economics of Mining in the Bitcoin Market

    OpenAIRE

    Cocco, Luisanna; Marchesi, Michele

    2016-01-01

    In January 3, 2009, Satoshi Nakamoto gave rise to the "Bitcoin Block Chain" creating the first block of the chain hashing on his computers central processing unit (CPU). Since then, the hash calculations to mine Bitcoin have been getting more and more complex, and consequently the mining hardware evolved to adapt to this increasing difficulty. Three generations of mining hardware have followed the CPU's generation. They are GPU's, FPGA's and ASIC's generations. This work presents an agent bas...

  5. Hydrogeochemical features of surface water and groundwater contaminated with acid mine drainage (AMD) in coal mining areas: a case study in southern Brazil.

    Science.gov (United States)

    Galhardi, Juliana Aparecida; Bonotto, Daniel Marcos

    2016-09-01

    Effects of acid mine drainage (AMD) were investigated in surface waters (Laranjinha River and Ribeirão das Pedras stream) and groundwaters from a coal mining area sampled in two different seasons at Figueira city, Paraná State, Brazil. The spatial data distribution indicated that the acid effluents favor the chemical elements leaching and transport from the tailings pile into the superficial water bodies or aquifers, modifying their quality. The acid groundwaters in both sampling periods (dry: pH 2.94-6.04; rainy: pH 3.25-6.63) were probably due to the AMD generation and infiltration, after the oxidation of sulfide minerals. Such acid effluents cause an increase of the solubilization rate of metals, mainly iron and aluminum, contributing to both groundwater and surface water contamination. Sulfate in high levels is a result of waters' pollution due to AMD. In some cases, high sulfate and low iron contents, associated with less acidic pH values, could indicate that AMD, previously generated, is nowadays being neutralized. The chemistry of the waters affected by AMD is controlled by the pH, sulfide minerals' oxidation, oxygen, iron content, and microbial activity. It is also influenced by seasonal variations that allow the occurrence of dissolution processes and the concentration of some chemical elements. Under the perspective of the waters' quality evaluation, the parameters such as conductivity, dissolved sodium, and sulfate concentrations acted as AMD indicators of groundwaters and surface waters affected by acid effluents.

  6. Manufacture of Cryoshroud Surfaces for Space Simulation Chambers

    Science.gov (United States)

    Ash, Gary S.

    2008-01-01

    Environmental test chambers for space applications use internal shrouds to simulate temperature conditions encountered in space. Shroud temperatures may range from +150 C to -253 C (20 K), and internal surfaces are coated with special high emissivity/absorptivity paints. To obtain temperature uniformity over large areas, detailed thermal design is required for placement of tubing for gaseous or liquid nitrogen and helium and other exotic heat exchange fluids. The recent increase in space simulation activity related to the James Webb Space Telescope has led to the design of new cryogenic shrouds to meet critical needs in instrument package testing. This paper will review the design and manufacturing of shroud surfaces for several of these programs, including fabrication methods and the selection and application of paints for simulation chambers.

  7. Mercury distribution in coals influenced by magmatic intrusions, and surface waters from the Huaibei Coal Mining District, Anhui, China

    International Nuclear Information System (INIS)

    Yan, Zhicao; Liu, Guijian; Sun, Ruoyu; Wu, Dun; Wu, Bin; Zhou, Chuncai

    2013-01-01

    Highlights: • Hg concentrations in coal and surface water samples were determined. • Hg is enriched in the Huaibei coals. • Magmatic activities imparted influences on Hg content and distribution. • Hg contents in surface waters are relative low at the present status. - Abstract: The Hg concentrations in 108 samples, comprising 81 coal samples, 1 igneous rock, 2 parting rock samples and 24 water samples from the Huaibei Coal Mining District, China, were determined by cold-vapor atomic fluorescence spectrometry. The abundance and distribution of Hg in different coal mines and coal seams were studied. The weighted average Hg concentration for all coal samples in the Huaibei Coalfield is 0.42 mg/kg, which is about twice that of average Chinese coals. From southwestern to northeastern coalfield, Hg concentration shows a decreasing trend, which is presumably related to magmatic activity and fault structures. The relatively high Hg levels are observed in coal seams Nos. 6, 7 and 10 in the southwestern coal mines. Correlation analysis indicates that Hg in the southwestern and southernmost coals with high Hg concentrations is associated with pyrite. The Hg concentrations in surface waters in the Huaibei Coal Mining District range from 10 to 60 ng/L, and display a decreasing trend with distance from a coal waste pile but are lower than the regulated levels for Hg in drinking water

  8. Simulating condensation on microstructured surfaces using Lattice Boltzmann Method

    Science.gov (United States)

    Alexeev, Alexander; Vasyliv, Yaroslav

    2017-11-01

    We simulate a single component fluid condensing on 2D structured surfaces with different wettability. To simulate the two phase fluid, we use the athermal Lattice Boltzmann Method (LBM) driven by a pseudopotential force. The pseudopotential force results in a non-ideal equation of state (EOS) which permits liquid-vapor phase change. To account for thermal effects, the athermal LBM is coupled to a finite volume discretization of the temperature evolution equation obtained using a thermal energy rate balance for the specific internal energy. We use the developed model to probe the effect of surface structure and surface wettability on the condensation rate in order to identify microstructure topographies promoting condensation. Financial support is acknowledged from Kimberly-Clark.

  9. Long-term effects of surface coal mining on ground-water levels and quality in two small watersheds in eastern Ohio

    International Nuclear Information System (INIS)

    Cunningham, W.L.; Jones, R.L.

    1990-01-01

    Two small eastern Ohio watersheds surface mined for coal and reclaimed were studied during 1986-89. Water level and water quality data were compared with data from investigations conducted during 1976-83 to determine long-term effects of surface mining on the hydrologic system. Before mining, the watersheds were characterized by flatlying sedimentary rocks above clay beds underlying two major coal seams. Two aquifers overlay each under clay. Surface mining removed the upper aquifer, stripped the coal seam, and replaced the spoil, creating a new aquifer with hydraulic and chemical characteristics different from those of the original upper aquifer. Water levels were measured continuously in one well in each aquifer and every 2 months in other wells. Water levels in upper aquifers reached hydraulic equilibrium from 2 to 5 years after mining and, in middle aquifers, water levels increased more than 5 ft during mining; equilibrium occurred almost immediately thereafter. Water samples were collected from three upper aquifer wells, one middle-aquifer well, a seep from the upper aquifer, and the stream in each watershed. Samples were collected in 1986, 1987, 1988, and 1989. In both watersheds, sulfate replaced bicarbonate as the dominant anion in the upper aquifer after mining. In general, significant increases in concentrations of dissolved constituents in groundwater resulted from surface mining. The continued decrease in pH indicates that groundwater had not reached complete geochemical equilibrium in either watershed more than 8 years after mining ended

  10. Finite element simulations of surface effect on Rayleigh waves

    Science.gov (United States)

    He, Jin; Zhao, Jinling

    2018-03-01

    Rayleigh waves influenced by surface effect are investigated by using finite element methods, in which eigenfrequency analysis are performed on a model composed of a half-space covered by the surface effect dominated domain. For a given wavelength, the frequency of the Rayleigh wave is obtained as the eigenfrequency of the model satisfying Floquet periodic boundary conditions. The thickness of the surface effect can be set to be infinitely small or a finite value in the finite element methods. The curvature-dependent out-of-plane force induced by surface tension as described by the generalized Young-Laplace equation is realized through geometric nonlinear analysis. The finite element simulations show that the assumptions of small curvature and infinitely small thickness of the surface effect widely used in theoretical approaches become invalid when Rayleigh waves are highly influenced by the surface effect. This work gives a more accurate insight into the surface effect on Rayleigh waves and provides a potential method for measuring the thickness of the surface effect from the dispersion curves of surface effect influenced Rayleigh wave velocities.

  11. Feasibility of a continuous surface mining machine using impact breakers. Phase I report, 1 October 1979-31 March 1980

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, A. T.; Simpson, R. J.

    1980-04-01

    This is the first phase report of the efforts to evaluate the feasibility of excavating coal and overburden from surface mines using impact breakers. Phase I is divided into four task groups. Those tasks are as follows: Selection of Field Sites for Parametric, Selection of Impact Hammers for Field, Design Test System, and Prepare Parametric Test Plan. A detailed description and accounting of each task is given in the body of this report. Included as appendices are the FMA internal reports on the individual mines visited. These reports are the basis of test site selection. The basic finding of this phase are that industry interest in the concept of impact mining tends toward the removal of multiple thin seams of coal and parting rather than deep coal or overburden and, while the intent of this contract is to explore the feasibility of impactors in a vertical array for use in a terraced mine plan, future design of a continuous mining machine should take industry acceptance into account.

  12. Research on the surface water quality in mining influenced area in north-western part of Romania

    Directory of Open Access Journals (Sweden)

    Smical Irina

    2015-01-01

    Full Text Available The paper highlights the current situation of the quality of surface water in the areas influenced by mining activities in the north-western part of Romania. In this respect a series of investigations have been conducted regarding the contamination with heavy metals of the water of the Someş and Tisa hydro- graphic Basins, which cover the northern part of Maramures County and the south-western area of Maramures County, respectively. The results of the comparative research refer to the period between 1999 and 2011 and reveal the specific heavy metal ions of mining activity: Fe, Mn, Zn, Cu, Pb Cd and Ni, as well as the water pH. The presented values as annual average values reveal an increase in several heavy metals after the closure of mines, which is due to the lack of effectiveness of the closure and of the conservation of the mine galleries, as well as of the impaired functioning of the mining wastewater treatment plants.

  13. Geochemical evolution of acidic ground water at a reclaimed surface coal mine in western Pennsylvania

    Science.gov (United States)

    Cravotta,, Charles A.

    1991-01-01

    Concentrations of dissolved sulfate and acidity in ground water increase downflow in mine spoil and underlying bedrock at a reclaimed surface coal mine in the bituminous field of western Pennsylvania. Elevated dissolved sulfate and negligible oxygen in ground water from bedrock about 100 feet below the water table suggest that pyritic sulfur is oxidized below the water table, in a system closed to oxygen. Geochemical models for the oxidation of pyrite (FeS2) and production of sulfate (SO42-) and acid (H+) are presented to explain the potential role of oxygen (O2) and ferric iron (Fe3+) as oxidants. Oxidation of pyrite by O2 and Fe3+ can occur under oxic conditions above the water table, whereas oxidation by Fe3+ also can occur under anoxic conditions below the water table. The hydrated ferric-sulfate minerals roemerite [Fe2+Fe43+(SO4)4·14H2O], copiapite [Fe2+Fe43+(SO4)6(OH)2·20H20], and coquimbite [Fe2(SO4)3·9H2O] were identified with FeS2 in coal samples, and form on the oxidizing surface of pyrite in an oxic system above the water table. These soluble ferric-sulfate 11 salts11 can dissolve with recharge waters or a rising water table releasing Fe3+, SO42-. and H+, which can be transported along closed-system ground-water flow paths to pyrite reaction sites where O2 may be absent. The Fe3+ transported to these sites can oxidize pyritic sulfur. The computer programs WATEQ4F and NEWBAL were used to compute chemical speciation and mass transfer, respectively, considering mineral dissolution and precipitation reactions plus mixing of waters from different upflow zones. Alternative mass-balance models indicate that (a) extremely large quantities of O2, over 100 times its aqueous solubility, can generate the observed concentrations of dissolved SO42- from FeS2, or (b) under anoxic conditions, Fe3+ from dissolved ferric-sulfate minerals can oxidize FeS2 along closed-system ground-water flow paths. In a system open to O2, such as in the unsaturated zone, the aqueous

  14. Simple model of surface roughness for binary collision sputtering simulations

    Science.gov (United States)

    Lindsey, Sloan J.; Hobler, Gerhard; Maciążek, Dawid; Postawa, Zbigniew

    2017-02-01

    It has been shown that surface roughness can strongly influence the sputtering yield - especially at glancing incidence angles where the inclusion of surface roughness leads to an increase in sputtering yields. In this work, we propose a simple one-parameter model (the "density gradient model") which imitates surface roughness effects. In the model, the target's atomic density is assumed to vary linearly between the actual material density and zero. The layer width is the sole model parameter. The model has been implemented in the binary collision simulator IMSIL and has been evaluated against various geometric surface models for 5 keV Ga ions impinging an amorphous Si target. To aid the construction of a realistic rough surface topography, we have performed MD simulations of sequential 5 keV Ga impacts on an initially crystalline Si target. We show that our new model effectively reproduces the sputtering yield, with only minor variations in the energy and angular distributions of sputtered particles. The success of the density gradient model is attributed to a reduction of the reflection coefficient - leading to increased sputtering yields, similar in effect to surface roughness.

  15. Simulating the Fate and Transport of an Acid Mine Drainage Release

    Science.gov (United States)

    On August 5, 2015, approximately 3 million gallons of acid mine drainage were released from the Gold King Mine into Cement Creek in the San Juan River watershed (CO, NM, UT). The release further mobilized additional metals, which resulted in a large mass of solids and dissolved m...

  16. Brine Migration from a Flooded Salt Mine in the Genesee Valley, Livingston County, New York: Geochemical Modeling and Simulation of Variable-Density Flow

    Science.gov (United States)

    Yager, Richard M.; Misut, Paul E.; Langevin, Christian D.; Parkhurst, David L.

    2009-01-01

    migrated beyond the collapse area, while simulations of pumping indicate that further upward migration of brine and saline water is now prevented by groundwater withdrawals under the brine-mitigation project. Geochemical modeling indicates that additional land subsidence as a result of anhydrite dissolution in the collapse area is not a concern, as long as the rate of brine pumping is less than the rate of upward flow of brine from the flooded mine. The collapse area above the flooded salt mine is within a glacially scoured bedrock valley that is filled with more than 150 meters of glacial drift. A confined aquifer at the bottom of the glacial sediments (referred to as the lower confined aquifer, or LCA) was the source of most of the water that flooded the mine. Two rubble chimneys that formed above the roof collapses in 1994 hydraulically connect the flooded mine to the LCA through 180 meters of sedimentary rock. From 1996 through 2006, water levels in the aquifer system recovered and the brine-displacement rate ranged from 4.4 to 1.6 liters per second, as estimated from land-surface subsidence above the mine. A zone of fracturing within the bedrock (the deformation zone) formed around the rubble chimneys as rock layers sagged toward the mine cavity after the roof collapses. Borehole geophysical surveys have identified three saline-water-bearing fracture zones in the bedrock: at stratigraphic contacts between the Onondaga and Bertie Limestones (O/B-FZ) and the Bertie Limestone and the Camillus Shale (B/C-FZ), and in the Syracuse Formation (Syr-FZ). The only outlets for brine displaced from the mine are through the rubble chimneys, but some of the brine could be diverted laterally into fracture zones in the rocks that lie between the mine and the LCA. Inverse geochemical models developed using PHREEQC indicate that halite brine in the flooded mine is derived from a mixture of freshwater from the LCA (81 percent), saline water from bedrock fracture zones (16 per

  17. Molecular Dynamics Simulations of Slip on Curved Surfaces

    Directory of Open Access Journals (Sweden)

    Ross D.A.

    2016-07-01

    Full Text Available We present Molecular Dynamics (MD simulations of liquid water confined within nanoscale geometries, including slit-like and cylindrical graphitic pores. These equilibrium results are used for calculating friction coefficients, which in turn can be used to calculate slip lengths. The slip length is a material property independent of the fluid flow rate. It is therefore a better quantity for study than the fluid velocity at the wall, also known as the slip velocity. Once the slip length has been found as a function of surface curvature, it can be used to parameterise Lattice Boltzmann (LB simulations. These larger scale simulations are able to tell us about how fluid transport is affected by slip in complex geometries; not just limited to single pores. Applications include flow and transport in nano-porous engine valve deposits and gas shales. The friction coefficient is found to be a function of curvature and is higher for fluid on convex surfaces and lower for concave surfaces. Both concave and convex surfaces approach the same value of the friction coefficient, which is constant above some critical radius of curvature, here found to be 7.4 ± 2.9 nm. The constant value of the friction coefficient is 10,000 ± 600 kg m−2 s−1, which is equivalent to a slip length of approximately 67 ± 4 nm.

  18. Real-time High-fidelity Surface Flow Simulation.

    Science.gov (United States)

    Ren, Bo; Yuan, Tailing; Li, Chenfeng; Xu, Kun; Hu, Shi-Min

    2017-06-30

    Surface flow phenomena, such as rain water flowing down a tree trunk and progressive water front in a shower room, are common in real life. However, compared with the 3D spatial fluid flow, these surface flow problems have been much less studied in the graphics community. To tackle this research gap, we present an efficient, robust and high-fidelity simulation approach based on the shallow-water equations. Specifically, the standard shallow-water flow model is extended to general triangle meshes with a feature-based bottom friction model, and a series of coherent mathematical formulations are derived to represent the full range of physical effects that are important for real-world surface flow phenomena. In addition, by achieving compatibility with existing 3D fluid simulators and by supporting physically realistic interactions with multiple fluids and solid surfaces, the new model is flexible and readily extensible for coupled phenomena. A wide range of simulation examples are presented to demonstrate the performance of the new approach.

  19. Modelling and simulation of surface morphology driven by ion bombardment

    Energy Technology Data Exchange (ETDEWEB)

    Yewande, E.O.

    2006-05-02

    Non-equilibrium surfaces, at nanometer length scales, externally driven via bombardment with energetic particles are known to exhibit well ordered patterns with a variety of applications in nano-technology. These patterns emerge at time scales on the order of minutes. Continuum theory has been quite successful in giving a general picture of the processes that interplay to give the observed patterns, as well as how such competition might determine the properties of the nanostructures. However, continuum theoretical descriptions are ideal only in the asymptotic limit. The only other theoretical alternative, which happens to be more suitable for the characteristic length-and time-scales of pattern formation, is Monte Carlo simulation. In this thesis, surface morphology is studied using discrete solid-on-solid Monte Carlo models of sputtering and surface diffusion. The simulations are performed in the context of the continuum theories and experiments. In agreement with the experiments, the ripples coarsen with time and the ripple velocity exhibits a power-law behaviour with the ripple wavelength, in addition, the exponent was found to depend on the simulation temperature, which suggests future experimental studies of flux dependence. Moreover, a detailed exploration of possible topographies, for different sputtering conditions, corresponding to different materials, was performed. And different surface topographies e.g. holes, ripples, and dots, were found at oblique incidence, without sample rotation. With sample rotation no new topography was found, its only role being to destroy any inherent anisotropy in the system. (orig.)

  20. Modelling and simulation of surface morphology driven by ion bombardment

    International Nuclear Information System (INIS)

    Yewande, E.O.

    2006-01-01

    Non-equilibrium surfaces, at nanometer length scales, externally driven via bombardment with energetic particles are known to exhibit well ordered patterns with a variety of applications in nano-technology. These patterns emerge at time scales on the order of minutes. Continuum theory has been quite successful in giving a general picture of the processes that interplay to give the observed patterns, as well as how such competition might determine the properties of the nanostructures. However, continuum theoretical descriptions are ideal only in the asymptotic limit. The only other theoretical alternative, which happens to be more suitable for the characteristic length-and time-scales of pattern formation, is Monte Carlo simulation. In this thesis, surface morphology is studied using discrete solid-on-solid Monte Carlo models of sputtering and surface diffusion. The simulations are performed in the context of the continuum theories and experiments. In agreement with the experiments, the ripples coarsen with time and the ripple velocity exhibits a power-law behaviour with the ripple wavelength, in addition, the exponent was found to depend on the simulation temperature, which suggests future experimental studies of flux dependence. Moreover, a detailed exploration of possible topographies, for different sputtering conditions, corresponding to different materials, was performed. And different surface topographies e.g. holes, ripples, and dots, were found at oblique incidence, without sample rotation. With sample rotation no new topography was found, its only role being to destroy any inherent anisotropy in the system. (orig.)

  1. Hydrologic assessment and numerical simulation of groundwater flow, San Juan Mine, San Juan County, New Mexico, 2010–13

    Science.gov (United States)

    Stewart, Anne M.

    2018-04-03

    Coal combustion byproducts (CCBs), which are composed of fly ash, bottom ash, and flue gas desulfurization material, produced at the coal-fired San Juan Generating Station (SJGS), located in San Juan County, New Mexico, have been buried in former surface-mine pits at the San Juan Mine, also referred to as the San Juan Coal Mine, since operations began in the early 1970s. This report, prepared by the U.S. Geological Survey in cooperation with the Mining and Minerals Division of the New Mexico Energy, Minerals and Natural Resources Department, describes results of a hydrogeologic assessment, including numerical groundwater modeling, to identify the timing of groundwater recovery and potential pathways for groundwater transport of metals that may be leached from stored CCBs and reach hydrologic receptors after operations cease. Data collected for the hydrologic assessment indicate that groundwater in at least one centrally located reclaimed surface-mining pit has already begun to recover.The U.S. Geological Survey numerical modeling package MODFLOW–NWT was used with MODPATH particle-tracking software to identify advective flow paths from CCB storage areas toward potential hydrologic receptors. Results indicate that groundwater at CCB storage areas will recover to the former steady state, or in some locations, groundwater may recover to a new steady state in 6,600 to 10,600 years at variable rates depending on the proximity to a residual cone-of-groundwater depression caused by mine dewatering and regional oil and gas pumping as well as on actual, rather than estimated, groundwater recharge and evapotranspirational losses. Advective particle-track modeling indicates that the number of particles and rates of advective transport will vary depending on hydraulic properties of the mine spoil, particularly hydraulic conductivity and porosity. Modeling results from the most conservative scenario indicate that particles can migrate from CCB repositories to either the

  2. Field and LiDAR observations of the Hector Mine California 1999 surface rupture

    Science.gov (United States)

    Sousa, F.; Akciz, S. O.; Harvey, J. C.; Hudnut, K. W.; Lynch, D. K.; Scharer, K. M.; Stock, J. M.; Witkosky, R.; Kendrick, K. J.; Wespestad, C.

    2014-12-01

    We report new field- and computer-based investigations of the surface rupture of the October 16, 1999 Hector Mine Earthquake. Since May 2012, in cooperation with the United States Marine Corps Air Ground Combat Center (MCAGCC) at Twentynine Palms, CA, our team has been allowed ground and aerial access to the entire surface rupture. We have focused our new field-based research and imagery analysis along the ~10 kilometer-long maximum slip zone (MSZ) which roughly corresponds to the zone of >4 meter dextral horizontal offset. New data include: 1) a 1 km wide aerial LiDAR survey along the entire surface rupture (@ 10 shots/m2, May 2012, www.opentopography.org); 2) terrestrial LiDAR surveys at 5 sites within the MSZ (@ >1000 shots/m2, April 2014); 3) low altitude aerial photography and ground based photography of the entire MSZ; 4) a ground-truthed database of 87 out of the 94 imagery-based offset measurements made within the MSZ; and 5) a database of 50 new field-based offset measurements made within the MSZ by our team on the ground, 31 of which have also been made on the computer (Ladicaoz) with both the 2000 LiDAR data (@ 0.5 m DEM resolution; Chen et al, in review) and 2012 LiDAR data (@ 35 cm DEM resolution; our team). New results to date include 1) significant variability (> 2 m) in horizontal offsets measured along short distances of the surface rupture (~100 m) within segments of the surface rupture that are localized to a single fault strand; 2) strong dependence of decadal scale fault scarp preservation on local lithology (bedrock vs. alluvial fan vs. fine sediment) and geomorphology (uphill vs. downhill facing scarp); 3) newly observed offset features which were never measured during the post-event field response; 4) newly observed offset features too small to be resolved in airborne LiDAR data (judged by our team to warrant removal from the database due to incorrect feature reconstruction; and 6) significant variability in both accuracy of LiDAR offset

  3. Sputtering of rough surfaces: a 3D simulation study

    Science.gov (United States)

    von Toussaint, U.; Mutzke, A.; Manhard, A.

    2017-12-01

    The lifetime of plasma-facing components is critical for future magnetic confinement fusion power plants. A key process limiting the lifetime of the first-wall is sputtering by energetic ions. To provide a consistent modeling of the sputtering process of realistic geometries, the SDTrimSP-code has been extended to enable the processing of analytic as well as measured arbitrary 3D surface morphologies. The code has been applied to study the effect of varying the impact angle of ions on rough surfaces on the sputter yield as well as the influence of the aspect ratio of surface structures on the 2D distribution of the local sputtering yields. Depending on the surface morphologies reductions of the effective sputter yields to less than 25% have been observed in the simulation results.

  4. Surface Ship Shock Modeling and Simulation: Two-Dimensional Analysis

    Directory of Open Access Journals (Sweden)

    Young S. Shin

    1998-01-01

    Full Text Available The modeling and simulation of the response of a surface ship system to underwater explosion requires an understanding of many different subject areas. These include the process of underwater explosion events, shock wave propagation, explosion gas bubble behavior and bubble-pulse loading, bulk and local cavitation, free surface effect, fluid-structure interaction, and structural dynamics. This paper investigates the effects of fluid-structure interaction and cavitation on the response of a surface ship using USA-NASTRAN-CFA code. First, the one-dimensional Bleich-Sandler model is used to validate the approach, and second, the underwater shock response of a two-dimensional mid-section model of a surface ship is predicted with a surrounding fluid model using a constitutive equation of a bilinear fluid which does not allow transmission of negative pressures.

  5. Scattering from objects and surfaces in room acoustical simulations

    DEFF Research Database (Denmark)

    Marbjerg, Gerd Høy; Brunskog, Jonas; Jeong, Cheol-Ho

    2016-01-01

    In room acoustical simulations, scattering objects are often modeled as impenetrable boxes with high scattering coefficients assigned to the surfaces. In some cases, a cluster of objects is modeled as a virtual impenetrable box, such that no sound propagation can take place between the objects....... Thus, the scattering only takes place on the boundary surfaces of the box and the acoustic volume of the room is reduced. Another challenge with representing scattering objects by reflecting surfaces is that it increases the number of surfaces, which greatly increases the calculation complexity...... for methods such as the image source method. In this paper a modeling method where the scattering from objects takes place in certain parts of the room volume is proposed. In this method, sound can still travel through scattering objects, but be partly scattered. This volume scattering method has at present...

  6. Thermal infrared remote sensing in assessing groundwater and surface-water resources related to Hannukainen mining development site, northern Finland

    Science.gov (United States)

    Rautio, Anne B.; Korkka-Niemi, Kirsti I.; Salonen, Veli-Pekka

    2018-02-01

    Mining development sites occasionally host complicated aquifer systems with notable connections to natural surface water (SW) bodies. A low-altitude thermal infrared (TIR) imaging survey was conducted to identify hydraulic connections between aquifers and rivers and to map spatial surface temperature patterns along the subarctic rivers in the proximity of the Hannukainen mining development area, northern Finland. In addition to TIR data, stable isotopic compositions ( δ 18O, δD) and dissolved silica concentrations were used as tracers to verify the observed groundwater (GW) discharge into the river system. Based on the TIR survey, notable GW discharge into the main river channel and its tributaries (61 km altogether) was observed and over 500 GW discharge sites were located. On the basis of the survey, the longitudinal temperature patterns of the studied rivers were found to be highly variable. Hydrological and hydrogeological information is crucial in planning and siting essential mining operations, such as tailing areas, in order to prevent any undesirable environmental impacts. The observed notable GW discharge was taken into consideration in the planning of the Hannukainen mining development area. The results of this study support the use of TIR imagery in GW-SW interaction and environmental studies in extensive and remote areas with special concerns for water-related issues but lacking the baseline research.

  7. Effects of Small-Scale Gold Mining on Surface and Ground Water ...

    African Journals Online (AJOL)

    / Prestea mining area in the Western Region of Ghana were conducted with the aim of assessing the possible effects of mining on water quality. Water samples were collected for 6 consecutive months at ten sampling sites within the study area ...

  8. Predicting events in the development of a coal surface mine in the west

    Science.gov (United States)

    Lynn M. Ferrante; Edward C. Thor

    1980-01-01

    Sudden changes in the level of coal mining activity in an area can cause immediate and profound changes in every facet of life in a rural community. Local officials and administrators of Federal and State governments often bear the brunt of responding to the disruptions that result from these changes. The nature of coal mining in the West is such that the community in...

  9. Use of barium-strontium carbonatite for flux welding and surfacing of mining machines

    Science.gov (United States)

    Kryukov, R. E.; Kozyrev, N. A.; Usoltsev, A. A.

    2017-09-01

    The results of application of barium-strontium carbonatite for modifying and refining iron-carbon alloys, used for welding and surfacing in ore mining and smelting industry, are generalized. The technology of manufacturing a flux additive containing 70 % of barium-strontium carbonatite and 30 % of liquid glass is proposed. Several compositions of welding fluxes based on silicomanganese slag were tested. The flux additive was introduced in an amount of 1, 3, 5 %. Technological features of welding with the application of the examined fluxes are determined. X-ray spectral analysis of the chemical composition of examined fluxes, slag crusts and weld metal was carried out, as well as metallographic investigations of welded joints. The principal possibility of applying barium-strontium carbonatite as a refining and gas-protective additive for welding fluxes is shown. The use of barium-strontium carbonatite reduces the contamination of the weld seam with nonmetallic inclusions: non-deforming silicates, spot oxides and brittle silicates, and increases the desulfurizing capacity of welding fluxes.

  10. Hydraulic Conductivity Modeling of Fractured Rock at Grasberg Surface Mine, Papua-Indonesia

    Directory of Open Access Journals (Sweden)

    Tedy Agung Cahyadi

    2017-04-01

    Full Text Available Packer tests and slug tests were conducted at 49 points at the Grasberg surface mine, Indonesia to obtain hydraulic conductivity data. The HC-system approach, which relies on rock quality designation, lithology permeability index, depth index, and gouge content designation, was applied. Geotechnical drill holes in 441 locations, consisting of 4,850 points of information, were used to determine the K values using the equation K = 2x10-6x HC0.5571. The K values, which were within the range of 10-8 and 10-5 m/s, were distributed into five alternative 3D distributions using Ordinary Kriging (OK and Artificial Neural Network (ANN. The result of the ANN modeling showed that some of the K values, with log K varying from -10.51 m/s to -3.09 m/s, were outside the range of the observed K values. The OK modeling results of K values, with log K varying from -8.12 m/s to -5.75 m/s, were within the range of the observed K values. The ANN modeled K values were slightly more varied than the OK modeled values. The result of an alternative OK modeling was chosen to represent the existing data population of flow media because it fits well to the geological conditions.

  11. Uranium in Surface Waters and Sediments Affected by Historical Mining in the Denver West 1:100,000 Quadrangle, Colorado

    Science.gov (United States)

    Zielinski, Robert A.; Otton, James K.; Schumann, R. Randall; Wirt, Laurie

    2008-01-01

    Geochemical sampling of 82 stream waters and 87 stream sediments within mountainous areas immediately west of Denver, Colorado, was conducted by the U.S. Geological Survey in October 1994. The primary purpose was to evaluate regionally the effects of geology and past mining on the concentration and distribution of uranium. The study area contains uranium- and thorium-rich bedrock, numerous noneconomic occurrences of uranium minerals, and several uranium deposits of variable size and production history. During the sampling period, local streams had low discharge and were more susceptible to uranium-bearing acid drainage originating from historical mines of base- and precious-metal sulfides. Results indicated that the spatial distribution of Precambrian granites and metamorphic rocks strongly influences the concentration of uranium in stream sediments. Within-stream transport increases the dispersion of uranium- and thorium rich mineral grains derived primarily from granitic source rocks. Dissolved uranium occurs predominantly as uranyl carbonate complexes, and concentrations ranged from less than 1 to 65 micrograms per liter. Most values were less than 5 micrograms per liter, which is less than the current drinking water standard of 30 micrograms per liter and much less than locally applied aquatic-life toxicity standards of several hundred micrograms per liter. In local streams that are affected by uranium-bearing acid mine drainage, dissolved uranium is moderated by dilution and sorptive uptake by stream sediments. Sorbents include mineral alteration products and chemical precipitates of iron- and aluminum-oxyhydroxides, which form where acid drainage enters streams and is neutralized. Suspended uranium is relatively abundant in some stream segments affected by nearby acid drainage, which likely represents mobilization of these chemical precipitates. The 234U/238U activity ratio of acid drainage (0.95-1.0) is distinct from that of local surface waters (more than 1

  12. A simulation of laser energy absorption by nanowired surface

    International Nuclear Information System (INIS)

    Vasconcelos, Miguel F.S.; Ramos, Alexandre F.

    2017-01-01

    Despite recent advances on research about laser inertial fusion energy, to increase the portion of energy absorbed by the target's surface from lasers remains as an important challenge. The plasma formed during the initial instants of laser arrival shields the target and prevents the absorption of laser energy by the deeper layers of the material. One strategy to circumvent that effect is the construction of targets whose surfaces are populated with nanowires. The nanowired surfaces have increased absorption of laser energy and constitutes a promising pathway for enhancing laser-matter coupling. In our work we present the results of simulations aiming to investigate how target's geometrical properties might contribute for maximizing laser energy absorption by material. Simulations have been carried out using the software FLASH, a multi-physics platform developed by researchers from the University of Chicago, written in FORTRAN 90 and Python. Different tools for generating target's geometry and analysis of results were developed using Python. Our results show that a nanowired surfaces has an increased energy absorption when compared with non wired surface. The software for visualization developed in this work also allowed an analysis of the spatial dynamics of the target's temperature, electron density, ionization levels and temperature of the radiation emitted by it. (author)

  13. Simulations of atomic trajectories near a dielectric surface

    Energy Technology Data Exchange (ETDEWEB)

    Stern, N P; Alton, D J; Kimble, H J, E-mail: hjkimble@caltech.edu [Norman Bridge Laboratory of Physics 12-33, California Institute of Technology, Pasadena, CA 91125 (United States)

    2011-08-15

    We present a semiclassical model of an atom moving in the evanescent field of a microtoroidal resonator. Atoms falling through whispering-gallery modes can achieve strong, coherent coupling with the cavity at distances of approximately 100 nm from the surface; in this regime, surface-induced Casmir-Polder level shifts become significant for atomic motion and detection. Atomic transit events detected in recent experiments are analyzed with our simulation, which is extended to consider atom trapping in the evanescent field of a microtoroid.

  14. Modeling and Simulation of the Economics of Mining in the Bitcoin Market.

    Directory of Open Access Journals (Sweden)

    Luisanna Cocco

    Full Text Available In January 3, 2009, Satoshi Nakamoto gave rise to the "Bitcoin Blockchain", creating the first block of the chain hashing on his computer's central processing unit (CPU. Since then, the hash calculations to mine Bitcoin have been getting more and more complex, and consequently the mining hardware evolved to adapt to this increasing difficulty. Three generations of mining hardware have followed the CPU's generation. They are GPU's, FPGA's and ASIC's generations. This work presents an agent-based artificial market model of the Bitcoin mining process and of the Bitcoin transactions. The goal of this work is to model the economy of the mining process, starting from GPU's generation, the first with economic significance. The model reproduces some "stylized facts" found in real-time price series and some core aspects of the mining business. In particular, the computational experiments performed can reproduce the unit root property, the fat tail phenomenon and the volatility clustering of Bitcoin price series. In addition, under proper assumptions, they can reproduce the generation of Bitcoins, the hashing capability, the power consumption, and the mining hardware and electrical energy expenditures of the Bitcoin network.

  15. Modeling and Simulation of the Economics of Mining in the Bitcoin Market.

    Science.gov (United States)

    Cocco, Luisanna; Marchesi, Michele

    2016-01-01

    In January 3, 2009, Satoshi Nakamoto gave rise to the "Bitcoin Blockchain", creating the first block of the chain hashing on his computer's central processing unit (CPU). Since then, the hash calculations to mine Bitcoin have been getting more and more complex, and consequently the mining hardware evolved to adapt to this increasing difficulty. Three generations of mining hardware have followed the CPU's generation. They are GPU's, FPGA's and ASIC's generations. This work presents an agent-based artificial market model of the Bitcoin mining process and of the Bitcoin transactions. The goal of this work is to model the economy of the mining process, starting from GPU's generation, the first with economic significance. The model reproduces some "stylized facts" found in real-time price series and some core aspects of the mining business. In particular, the computational experiments performed can reproduce the unit root property, the fat tail phenomenon and the volatility clustering of Bitcoin price series. In addition, under proper assumptions, they can reproduce the generation of Bitcoins, the hashing capability, the power consumption, and the mining hardware and electrical energy expenditures of the Bitcoin network.

  16. Modeling and Simulation of the Economics of Mining in the Bitcoin Market

    Science.gov (United States)

    Marchesi, Michele

    2016-01-01

    In January 3, 2009, Satoshi Nakamoto gave rise to the “Bitcoin Blockchain”, creating the first block of the chain hashing on his computer’s central processing unit (CPU). Since then, the hash calculations to mine Bitcoin have been getting more and more complex, and consequently the mining hardware evolved to adapt to this increasing difficulty. Three generations of mining hardware have followed the CPU’s generation. They are GPU’s, FPGA’s and ASIC’s generations. This work presents an agent-based artificial market model of the Bitcoin mining process and of the Bitcoin transactions. The goal of this work is to model the economy of the mining process, starting from GPU’s generation, the first with economic significance. The model reproduces some “stylized facts” found in real-time price series and some core aspects of the mining business. In particular, the computational experiments performed can reproduce the unit root property, the fat tail phenomenon and the volatility clustering of Bitcoin price series. In addition, under proper assumptions, they can reproduce the generation of Bitcoins, the hashing capability, the power consumption, and the mining hardware and electrical energy expenditures of the Bitcoin network. PMID:27768691

  17. Computer simulation of RBS spectra from samples with surface roughness

    Czech Academy of Sciences Publication Activity Database

    Malinský, Petr; Hnatowicz, Vladimír; Macková, Anna

    2016-01-01

    Roč. 371, MAR (2016), s. 101-105 ISSN 0168-583X. [22nd International conference on Ion Beam Analysis (IBA). Opatija, 14.06.2015-19.06.2015] R&D Projects: GA MŠk(CZ) LM2011019; GA ČR GA15-01602S Institutional support: RVO:61389005 Keywords : computer simulation * Rutherford backscattering * surface roughness Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.109, year: 2016

  18. Simulated flow of groundwater and brine from a flooded salt mine in Livingston County, New York, and effects of remedial pumping on an overlying aquifer

    Science.gov (United States)

    Yager, Richard M.; Miller, Todd S.; Kappel, William M.; Misut, Paul E.; Langevin, Christian D.; Parkhurst, David L.; deVries, M. Peter

    2012-01-01

    Two ceiling collapses in the Retsof salt mine near Geneseo in upstate New York in spring 1994 resulted in the upward propagation of two columns of rubble through 600 feet of overlying shale and carbonate bedrock. This upward propagation formed a hydraulic connection between the lower confined aquifer (LCA) and the mine and allowed water from the aquifer and bedrock fracture zones that intersected the rubble columns to flow into the mine at a rate of 18,000 gallons per minute (gal/min) . All salt mining ceased in September 1995, and the mine was completely flooded by January 1996. The flow of water from the lower confined aquifer into the mine caused widespread drawdowns, and water levels in the aquifer declined by as much as 400 feet near the collapse area and by more than 50 feet at wells 7 miles to the north and south. Within 3 to 4 weeks of the collapses, water levels in about a dozen domestic and industrial wells had declined severely, and some wells went dry. Water levels in at least 58 wells in the lower and middle confined aquifers were affected by mine flooding. Groundwater in the upper unconfined aquifer and surface water in streams were unaffected by water-level drawdown, but channels of the Genesee River and Beards Creek were altered by land subsidence related to the mine collapse. Water levels recovered from 1996 through 2006, but the mine is now filled with about 15 billion gallons of saturated halite brine. The weight of the overlying rock and sediment is expected to cause the salt beds to deform and fill the mine cavity during the next several hundred years; this in turn could displace as much as 80 percent of the brine and cause it to move upward through the rubble chimneys, rendering the LCA unusable as a source of water supply. Saline water was detected in the LCA in 2002 but was found to be derived primarily from fractures in the limestone and shale units between the mine and the LCA, rather than from the mine. In September 2006, the mine company

  19. Min(d)ing the land: The relationship between artisanal and small-scale mining and surface land arrangements in the southern Philippines, eastern DRC and Liberia

    NARCIS (Netherlands)

    Verbrugge, B.L.P.; Cuvelier, J.; Bockstael, S. van

    2015-01-01

    This article examines the relationship between artisanal and small-scale mining (ASM) and surface land tenure arrangements, through a comparison of mining areas in the southern Philippines, the eastern DRC and Liberia. In all three cases, ASM takes place in peripheral regions outside central state

  20. Restoration of intact ground waters and surface waters in the post-mining landscape; Wiederherstellung intakter Grund- und Oberflaechengewaesser nach dem Braunkohlenbergbau

    Energy Technology Data Exchange (ETDEWEB)

    Merkel, Broder; Schipek, Mandy [Technische Univ. Bergakademie Freiberg (Germany); Scholz, Guenter; Rabe, Wolfgang; Clauss, Denny [MOVAB-D GmbH, Lauta (Germany)

    2011-12-15

    The restoration of the territories of former brown coal mining increasingly requires special efforts for the protection of affected ground waters and surface waters. With newly developed methods (the so-called inlake technology), recently various solutions to neutralize acidic mining lakes could be created. Simultaneously, this improves the water quality of adjacent aquifers at reasonable financial cost.

  1. Two dimensional simulation of high power laser-surface interaction

    International Nuclear Information System (INIS)

    Goldman, S.R.; Wilke, M.D.; Green, R.E.L.; Johnson, R.P.; Busch, G.E.

    1998-01-01

    For laser intensities in the range of 10 8 --10 9 W/cm 2 , and pulse lengths of order 10 microsec or longer, the authors have modified the inertial confinement fusion code Lasnex to simulate gaseous and some dense material aspects of the laser-matter interaction. The unique aspect of their treatment consists of an ablation model which defines a dense material-vapor interface and then calculates the mass flow across this interface. The model treats the dense material as a rigid two-dimensional mass and heat reservoir suppressing all hydrodynamic motion in the dense material. The computer simulations and additional post-processors provide predictions for measurements including impulse given to the target, pressures at the target interface, electron temperatures and densities in the vapor-plasma plume region, and emission of radiation from the target. The authors will present an analysis of some relatively well diagnosed experiments which have been useful in developing their modeling. The simulations match experimentally obtained target impulses, pressures at the target surface inside the laser spot, and radiation emission from the target to within about 20%. Hence their simulational technique appears to form a useful basis for further investigation of laser-surface interaction in this intensity, pulse-width range. This work is useful in many technical areas such as materials processing

  2. Simulating Sediment Sorting of Streambed Surfaces - It's the Supply, Stupid

    Science.gov (United States)

    Wilcock, P. R.

    2014-12-01

    The grain size of the streambed surface is an integral part of the transport system because it represents the grains immediately available for transport. If the rate and size of grains entrained from the bed surface differ from that delivered to the bed surface, the bed surface grain size will change. Although this balance is intuitively clear, its implications can surprise. The relative mobility of different sizes in a mixture change as transport rates increase. At small transport rates, smaller sizes are more mobile. As transport rate increases, the transport grain size approaches that of the bed. This presents a dilemma when using flumes to simulate surface sorting and transport. When sediment is fed into a flume, the same sediment is typically used regardless of feed rate. The transport grain size remains constant at all rates, which does not match the pattern observed in the field. This operational constraint means that sediment supply is coarser than transport capacity in feed flumes, increasingly so as transport rates diminish. This imbalance drives a coarsening of the stream bed as less mobile coarse grains concentrate on the surface as the system approaches steady-state. If sediment is recirculated in a flume, sediment supply and entrainment are perfectly matched. Surface coarsening is not imposed, but does occur via kinematic sieving. The coarsening of the transport (and supply) accommodates the rate-dependent change in mobility such that the bed surface grain size does not change with transport rate. Streambed armoring depends on both the rate and grain size of sediment supply - their implications do not seem to be fully appreciated. A coarsened bed surface does not indicate sorting of the bed surface during waning flows - it can persist with active sediment supply and transport. Neither sediment feed nor sediment recirculating flumes accurately mimic natural conditions but instead represent end members that bracket the dynamics of natural streams

  3. Solutions Network Formulation Report. Landsat Data Continuity Mission Simulated Data Products for Bureau of Land Management and Environmental Protection Agency Abandoned Mine Lands Decision Support

    Science.gov (United States)

    Estep, Leland

    2007-01-01

    Presently, the BLM (Bureau of Land Management) has identified a multitude of abandoned mine sites in primarily Western states for cleanup. These sites are prioritized and appropriate cleanup has been called in to reclaim the sites. The task is great in needing considerable amounts of agency resources. For instance, in Colorado alone there exists an estimated 23,000 abandoned mines. The problem is not limited to Colorado or to the United States. Cooperation for reclamation is sought at local, state, and federal agency level to aid in identification, inventory, and cleanup efforts. Dangers posed by abandoned mines are recognized widely and will tend to increase with time because some of these areas are increasingly used for recreation and, in some cases, have been or are in the process of development. In some cases, mines are often vandalized once they are closed. The perpetrators leave them open, so others can then access the mines without realizing the danger posed. Abandoned mine workings often fill with water or oxygen-deficient air and dangerous gases following mining. If the workings are accidentally entered into, water or bad air can prove fatal to those underground. Moreover, mine residue drainage negatively impacts the local watershed ecology. Some of the major hazards that might be monitored by higher-resolution satellites include acid mine drainage, clogged streams, impoundments, slides, piles, embankments, hazardous equipment or facilities, surface burning, smoke from underground fires, and mine openings.

  4. Predictive modelling of the mine water rebound in an old abandoned Dongwon mine in Korea

    Science.gov (United States)

    Baek, Hwanjo; Kim, Daehoon; Park, Seunghwan; Kim, Gyoungman

    2014-05-01

    The closure of over three-hundred deep coal mines in Korea since the late-1980s, primarily due to the energy and environmental concerns, has produced significant side effects. One of the major challenges is to assess the risk from mine water rebound to overlying aquifers and surface waters, which can produce significant environmental hazards. Some numerical models such as VSS-NET, GRAM and MODFLOW have been developed to predict the quantity, timing and location of discharges resulting from mine water rebound. In this study, we developed a GRAM-based windows program for mine water rebound modelling in abandoned deep mine systems. The program consists of the simulation engine and the GUI modules, each has several subroutines. Changes in mine water level of the Dongwon coal mine, presumably hydrogeologically connected to nearby old abandoned mines, has been monitored after the mine was finally closed in 2005. The water level in the vertical shaft rised up to 420m during the period of 3 years. The system was modelled as two ponds connected by a pipe. Input data include the areas of each pond, catchment areas, the storage coefficient, etc. The predicted changes in the mine water level was very similar to the observed data in the field. For this modelling, in fact, some of the input variable were roughly assumed to match the field data. Nevertheless, this program can be effectively applied to predict the rising of the mine water after the mine closure.

  5. Improved simulation of groundwater - surface water interaction in catchment models

    Science.gov (United States)

    teklesadik, aklilu; van Griensven, Ann; Anibas, Christian; Huysmans, Marijke

    2016-04-01

    Groundwater storage can have a significant contribution to stream flow, therefore a thorough understanding of the groundwater surface water interaction is of prime important when doing catchment modeling. The aim of this study is to improve the simulation of groundwater - surface water interaction in a catchment model of the upper Zenne River basin located in Belgium. To achieve this objective we used the "Groundwater-Surface water Flow" (GSFLOW) modeling software, which is an integration of the surface water modeling tool "Precipitation and Runoff Modeling system" (PRMS) and the groundwater modeling tool MODFLOW. For this case study, the PRMS model and MODFLOW model were built and calibrated independently. The PRMS upper Zenne River basin model is divided into 84 hydrological response units (HRUs) and is calibrated with flow data at the Tubize gauging station. The spatial discretization of the MODFLOW upper Zenne groundwater flow model consists of 100m grids. Natural groundwater divides and the Brussels-Charleroi canal are used as boundary conditions for the MODFLOW model. The model is calibrated using piezometric data. The GSFLOW results were evaluated against a SWAT model application and field observations of groundwater-surface water interactions along a cross section of the Zenne River and riparian zone. The field observations confirm that there is no exchange of groundwater beyond the Brussel-Charleroi canal and that the interaction at the river bed is relatively low. The results show that there is a significant difference in the groundwater simulations when using GSFLOW versus SWAT. This indicates that the groundwater component representation in the SWAT model could be improved and that a more realistic implementation of the interactions between groundwater and surface water is advisable. This could be achieved by integrating SWAT and MODFLOW.

  6. Exposing earth surface process model simulations to a large audience

    Science.gov (United States)

    Overeem, I.; Kettner, A. J.; Borkowski, L.; Russell, E. L.; Peddicord, H.

    2015-12-01

    The Community Surface Dynamics Modeling System (CSDMS) represents a diverse group of >1300 scientists who develop and apply numerical models to better understand the Earth's surface. CSDMS has a mandate to make the public more aware of model capabilities and therefore started sharing state-of-the-art surface process modeling results with large audiences. One platform to reach audiences outside the science community is through museum displays on 'Science on a Sphere' (SOS). Developed by NOAA, SOS is a giant globe, linked with computers and multiple projectors and can display data and animations on a sphere. CSDMS has developed and contributed model simulation datasets for the SOS system since 2014, including hydrological processes, coastal processes, and human interactions with the environment. Model simulations of a hydrological and sediment transport model (WBM-SED) illustrate global river discharge patterns. WAVEWATCH III simulations have been specifically processed to show the impacts of hurricanes on ocean waves, with focus on hurricane Katrina and super storm Sandy. A large world dataset of dams built over the last two centuries gives an impression of the profound influence of humans on water management. Given the exposure of SOS, CSDMS aims to contribute at least 2 model datasets a year, and will soon provide displays of global river sediment fluxes and changes of the sea ice free season along the Arctic coast. Over 100 facilities worldwide show these numerical model displays to an estimated 33 million people every year. Datasets storyboards, and teacher follow-up materials associated with the simulations, are developed to address common core science K-12 standards. CSDMS dataset documentation aims to make people aware of the fact that they look at numerical model results, that underlying models have inherent assumptions and simplifications, and that limitations are known. CSDMS contributions aim to familiarize large audiences with the use of numerical

  7. Longwall mining and surface deformation – lessons learned from dInSAR measurements

    CSIR Research Space (South Africa)

    Engelbrecht, Jeanine

    2016-08-01

    Full Text Available including 1) subsidence related to mining and groundwater abstraction, 2) deformation following earthquake events, 3) monitoring of landslides and slope stability, 4) monitoring the stability of infrastructure and large engineering works, and 5) monitoring...

  8. Noble Gas Surface Flux Simulations And Atmospheric Transport

    Energy Technology Data Exchange (ETDEWEB)

    Carrigan, Charles R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sun, Yunwei [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Simpson, Matthew D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-09-30

    Signatures from underground nuclear explosions or UNEs are strongly influenced by the containment regime surrounding them. The degree of gas leakage from the detonation cavity to the surface obviously affects the magnitude of surface fluxes of radioxenon that might be detected during the course of a Comprehensive Test Ban Treaty On-Site Inspection. In turn, the magnitude of surface fluxes will influence the downwind detectability of the radioxenon atmospheric signature from the event. Less obvious is the influence that leakage rates have on the evolution of radioxenon isotopes in the cavity or the downwind radioisotopic measurements that might be made. The objective of this letter report is to summarize our attempt to better understand how containment conditions affect both the detection and interpretation of radioxenon signatures obtained from sampling at the ground surface near an event as well as at greater distances in the atmosphere. In the discussion that follows, we make no attempt to consider other sources of radioactive noble gases such as natural backgrounds or atmospheric contamination and, for simplicity, only focus on detonation-produced radioxenon gases. Summarizing our simulations, they show that the decay of radioxenon isotopes (e.g., Xe-133, Xe-131m, Xe-133m and Xe-135) and their migration to the surface following a UNE means that the possibility of detecting these gases exists within a window of opportunity. In some cases, seeps or venting of detonation gases may allow significant quantities to reach the surface and be released into the atmosphere immediately following a UNE. In other release scenarios – the ones we consider here – hours to days may be required for gases to reach the surface at detectable levels. These release models are most likely more characteristic of “fully contained” events that lack prompt venting, but which still leak gas slowly across the surface for periods of months.

  9. Spatial variation in spoil and vegetative characteristics of pastures on reclaimed surface mined land

    International Nuclear Information System (INIS)

    Teutsch, C.D.; Collins, M.; Ditsch, D.C.

    1999-01-01

    Kentucky has large areas of reclaimed surface mined land that could provide grazing for livestock. Research is needed to determine optimal stocking densities and to evaluate the sustainability of such grazing systems for this region. A long-term grazing study was initiated in 1997 on 151 ha of reclaimed land near Chavies, KY to determine spatial and temporal variation with stocking densities of 0, 0.28, 0.42, or 0.83 beef cow-calf units/ha. Global Positioning System and GIS technologies were used to establish pasture boundaries, locate permanent sampling markers at a density of 1 per 0.4 ha, and interpolate maps of physical, spoil, and vegetable pasture characteristics. Herbage and spoil samples were collected around the permanent markers in May of 1997. Stepwise regression was used to determine factors affecting the vegetative characteristics of the sites. Biomass density ranged from 0 to 2500 kg/ha with a mean of 570 kg/ha. Factors affecting biomass included legume and weed proportions in the sward, grazing activity, soil potassium, elevation, and potential acidity, cumulatively accounting for 32% of the variation. Ground cover ranged from 10 to 100% with an average of 74%. Soil pH, potassium, and grass in the sward accounted for 14% of the variation in ground cover. Legumes made up 0 to 61% of the sward with a mean of 13% over the pasture area. Variables affecting the amount of legume in the sward included biomass density, slope, elevation, pH, and stocking density, together accounting for 21% of the variation. Spatial variation in the physical, spoil, and vegetative characteristics of the pastures was large. Overall, regression accounted for a limited amount of the variation in the vegetative characteristics of the site indicating that other important variables exist

  10. Environmental impact of coal mining and coal seam gas production on surface water quality in the Sydney basin, Australia.

    Science.gov (United States)

    Ali, A; Strezov, V; Davies, P; Wright, I

    2017-08-01

    The extraction of coal and coal seam gas (CSG) will generate produced water that, if not adequately treated, will pollute surface and groundwater systems. In Australia, the discharge of produced water from coal mining and related activities is regulated by the state environment agency through a pollution licence. This licence sets the discharge limits for a range of analytes to protect the environment into which the produced water is discharged. This study reports on the impact of produced water from coal mine activities located within or discharging into high conservation environments, such as National Parks, in the outer region of Sydney, Australia. The water samples upstream and downstream from the discharge points from six mines were taken, and 110 parameters were tested. The results were assessed against a water quality index (WQI) which accounts for pH, turbidity, dissolved oxygen, biochemical oxygen demand, total dissolved solids, total phosphorus, nitrate nitrogen and E .coli. The water quality assessment based on the trace metal contents against various national maximum admissible concentration (MAC) and their corresponding environmental impacts was also included in the study which also established a base value of water quality for further study. The study revealed that impacted water downstream of the mine discharge points contained higher metal content than the upstream reference locations. In many cases, the downstream water was above the Australia and New Zealand Environment Conservation Council and international water quality guidelines for freshwater stream. The major outliers to the guidelines were aluminium (Al), iron (Fe), manganese (Mn), nickel (Ni) and zinc (Zn). The WQI of surface water at and downstream of the discharge point was lower when compared to upstream or reference conditions in the majority of cases. Toxicology indices of metals present in industrial discharges were used as an additional tool to assess water quality, and the newly

  11. Molecular dynamics simulation of uranium compound adsorption on solid surface

    International Nuclear Information System (INIS)

    Omori, Yuki; Takizawa, Yuji; Okamoto, Tsuyoshi

    2010-01-01

    Particles mixed in the UF6 gas have the property of accumulating on the inside of piping or units. This type of accumulation will cause material unaccounted for (MUF) in the UF6 gas processing facilities. Development of a calculation model for estimating the accumulation rate of uranium compounds has been expected. And predicting possible part of the units where uranium compounds adsorb will contribute to design an effective detection system. The purpose of this study is to take the basic knowledge of the particle's adsorption mechanism from the microscopic point of view. In simulation analysis, UF5 model particle is produced, then two types of solid surfaces are prepared; one is a solid surface at rest and the other is a moving solid surface. The result obtained by the code 'PABS' showed that when the solid surface moves at a lower velocity, the particle's adsorption process dominates over the particle's breakup one. Besides the velocity of the solid surface, other principal factors affecting an adsorption ratio were also discussed. (author)

  12. Statistical Characterization of Electromagnetic Wave Propagation in Mine Environments

    KAUST Repository

    Yucel, Abdulkadir C.

    2013-01-01

    A computational framework for statistically characterizing electromagnetic (EM) wave propagation through mine tunnels and galleries is presented. The framework combines a multi-element probabilistic collocation method with a full-wave fast Fourier transform and fast multipole method accelerated surface integral equation-based EM simulator to statistically characterize fields from wireless transmitters in complex mine environments. 1536-1225 © 2013 IEEE.

  13. Groundwater Surface Water Interactions in a Gold-Mined Dredged Floodplain of the Merced River

    Science.gov (United States)

    Sullivan, L.; Conklin, M. H.; Ghezzehei, T. A.

    2012-12-01

    The Merced River, originating in the Sierra Nevada, California, drains a watershed with an area of ~3,305 km2. Merced River has been highly altered due to diversions, mechanically dredged mining, and damming. A year of groundwater-surface water interactions were studied to elucidate the hydrological connection between the Main Canal, an unlined canal that contains Merced River water flows parallel to the river with an average elevation of 89m, the highly conductive previously dredged floodplain, and the Merced River with an average elevation of 84m. Upstream of the study reach, located in an undredged portion, of the floodplain are two fish farms that have been operating for approximately 40 years. This study reach has been historically important for salmon spawning and rearing, where more than 50% of the Chinook salmon of the Merced River spawn. Currently salmon restoration is focusing gravel augmentation and adding side channel and ignoring groundwater influences. Exchanges between the hyporheic and surrounding surface, groundwater, riparian, and alluvial floodplain habitats occur over a wide range of spatial and temporal scales. Pressure transducers were installed in seven wells and four ponds located in the dredged floodplain. All wells were drilled to the Mehrten Formation, a confining layer, and screened for last 3m. These groundwater well water levels as well as the surface water elevations of the Main Canal and the Merced River were used to determine the direction of sublateral surface flows using Groundwater Vistas as a user interface for MODFLOW. The well and pond waters and seepage from the river banks were sampled for anion/cation, dissolved organic carbon, total nitrogen, total iron, and total dissolved iron concentrations to determine water sources and the possibility of suboxic water. Field analysis indicated that water in all wells and ponds exhibit low dissolved oxygen, high conductivity rates, and oxidation/reduction potentials that switched from

  14. Methodology of simulation of underground working in metal mines. Application to a uranium deposit in Australia

    International Nuclear Information System (INIS)

    Deraisme, J.; de Fouquet, C.; Fraisse, H.

    1983-01-01

    For the Ben Lomond (Northern Queensland Australia) underground uranium mining project, studies were carried out to compare the feasibility of different mining methods according to their cost per ton and selectivity, i.e. cut and fill, sublevel stopping and both mixed. First, a geostatistical orebody model was built. The ore grade variability of this model results from the drillhole structural analysis. Working on two dimensional vertical cross sections, the usual hand drawing stope reserve estimate obtained with computer assisted design for each of the three different mining methods is compared with the results obtained with automatic algorithms allocated to the characteristics of each mining method. These algorithms use mathematical morphology to reproduce the geometrical constraints connected with each mining method and/or dynamic programmation. These techniques lead to fully automatic of optimal economical stope design. Comparison is positive: automatic stopes designs are in agreement with hand made drawings, but they can be defined faster through interactive questionning of the computer, and the total maximum profit obtained is a least as high as the best profit found through hand designed projects [fr

  15. Solvent accessible surface area (ASA) of simulated phospholipid membranes

    DEFF Research Database (Denmark)

    Tuchsen, E.; Jensen, Morten Østergaard; Westh, P.

    2003-01-01

    The membrane-solvent interface has been investigated through calculations of the solvent accessible surface area (ASA) for simulated membranes of DPPC and POPE. For DPPC at 52 degreesC we found an ASA of 126 +/- 8 Angstrom(2) per lipid molecule, equivalent to twice the projected lateral area......, even the most exposed parts of the PC head-group show average ASAs of less than half of its maximal or 'fully hydrated' value. The average ASA of a simulated POPE membrane was 96 +/- 7 Angstrom(2) per lipid. The smaller value than for DPPC reflects much lower ASA of the ammonium ion, which is partially...... compensated by increased exposure of the ethylene and phosphate moieties. The ASA of the polar moieties Of (PO4, NH3 and COO) constitutes 65% of the total accessible area for POPE, making this interface more polar than that of DPPC. It is suggested that ASA information can be valuable in attempts...

  16. View-Dependent Tessellation and Simulation of Ocean Surfaces

    Directory of Open Access Journals (Sweden)

    Anna Puig-Centelles

    2014-01-01

    Full Text Available Modeling and rendering realistic ocean scenes have been thoroughly investigated for many years. Its appearance has been studied and it is possible to find very detailed simulations where a high degree of realism is achieved. Nevertheless, among the solutions to ocean rendering, real-time management of the huge heightmaps that are necessary for rendering an ocean scene is still not solved. We propose a new technique for simulating the ocean surface on GPU. This technique is capable of offering view-dependent approximations of the mesh while maintaining coherence among the extracted approximations. This feature is very important as most solutions previously presented must retessellate from the initial mesh. Our solution is able to use the latest extracted approximation when refining or coarsening the mesh.

  17. Evaluating the Use of Tree Shelters for Direct Seeding of Castanea on a Surface Mine in Appalachia

    Directory of Open Access Journals (Sweden)

    Christopher Barton

    2015-10-01

    Full Text Available American chestnut (Castanea dentata, once a primary constituent of the eastern hardwood forest ecosystem, was nearly extirpated from the forest canopy by the accidental introduction of chestnut blight (Cryphonectria parasitica. An intensive breeding program has sought to breed blight resistance from Chinese chestnut into American chestnuts, while maintaining as much of the desirable American chestnut phenotypes as possible. Previous studies suggest that these blight resistant American chestnuts, termed “restoration chestnuts”, are capable of thriving on reclaimed surface mines. We direct seeded pure Chinese, pure American, and three backcross lines into brown sandstone minesoil on a mine site in Pike County, KY. To investigate the effects of tree sheltering on survival and growth, we installed tree shelters on half the plots, and left the rest of the plots unsheltered. Results indicated that shelters were highly effective at reducing initial mortality. In addition, while pure Chinese chestnut survival was highest, the three backcross lines have also survived well on this site. Our study demonstrates that American, Chinese, and backcrossed chestnuts can survive through five growing seasons on reclaimed surface mines with the use of tree shelters.

  18. Effects of surface coal mining and reclamation on the geohydrology of six small watersheds in west-central Indiana. Chapter B

    International Nuclear Information System (INIS)

    Martin, J.D.; Duwelius, R.F.; Crawford, C.G.

    1990-01-01

    Coal has been and will continue to be a major source of energy in the United States for the foreseeable future. Surface mining is presently the most efficient method of extracting coal. The mining practice, however, usually has a detrimental effect on the environment by altering topography and ecologic systems. Surface coal mining also can degrade surface- and ground-water quality and quantity. The U.S. Geological Survey began a study in 1979 to identify changes in the quantity of surface- and ground-water resources caused by surface coal mining in Indiana. As part of the study, six small watersheds in west-central Indiana were instrumented for the collection of hydrologic and meteorologic data. The Water-Supply Paper comprises two reports resulting from the investigation. The physical environment and coal mining history of west-central Indiana and the six small watersheds selected for intensive study are described in chapter A. The surface- and ground-water systems of each of the small watersheds and the hydrologic effects of coal mining and reclamation are described in chapter B

  19. Simulation of gas compressible flow by free surface water flow

    International Nuclear Information System (INIS)

    Altafini, C.R.; Silva Ferreira, R.T. da

    1981-01-01

    The analogy between the water flow with a free surface and the compressible fluid flow, commonly called hydraulic analogy, is analyzed and its limitations are identified. The water table is the equipment used for this simulation, which allows the quatitative analysis of subsonic and supersonic flow with a low cost apparatus. The hydraulic analogy is applied to subsonic flow around circular cylinders and supersonic flow around cones. The results are compared with available theoretical and experimental data and a good agreement is achieved. (Author) [pt

  20. Ergonomics - Using Ergonomics to Enhance Safe Production at a Surface Coal Mine - A Case Study with Powder Crews

    Energy Technology Data Exchange (ETDEWEB)

    Torma-Krajewski, J.; Wiehagen, W.; Etcheverry, A.; Turin, F.; Unger, R. [Colorado School of Mines, Golden, CO (United States)

    2009-07-01

    Job tasks that involve exposure to work-related musculoskeletal disorder (WMSD) risk factors may impact both the risk of injury and production downtime. Common WMSD risks factors associated with mining tasks include forceful exertions, awkward postures, repetitive motion, jolting and jarring, forceful gripping, contact stress, and whole body and segmental vibration. Mining environments that expose workers to temperature/humidity extremes, windy conditions, and slippery and uneven walking surfaces also contribute to injury risk. National Institute for Occupational Safety and Health (NIOSH) researchers worked with powder crew members from the Bridger Coal Company to identify and rank routine work tasks based on perceived exposure to WMSD risk factors. This article presents the process followed to identify tasks that workers believed involved the greatest exposure to risk factors and discusses risk reduction strategies. Specifically, the proposed prill truck design changes addressed cab ingress/egress, loading blast holes, and access to the upper deck of the prill truck.

  1. Unexpected hydrologic perturbation in an abandoned underground coal mine: Response to surface reclamation?

    Science.gov (United States)

    Harper, D.; Olyphant, G.A.; Hartke, E.J.

    1990-01-01

    A reclamation project at the abandoned Blackhawk Mine site near Terre Haute, Indiana, lasted about four months and involved the burial of coarse mine refuse in shallow (less than 9 m) pits excavated into loess and till in an area of about 16 ha. An abandoned flooded underground coal mine underlies the reclamation site at a depth of about 38 m; the total area underlain by the mine is about 10 km2. The potentiometric levels associated with the mine indicate a significant (2.7 m) and prolonged perturbation of the deeper confined groundwater system; 14 months after completing reclamation, the levels began to rise linearly (at an average rate of 0.85 cm/d) for 11 months, then fell exponentially for 25 months, and are now nearly stable. Prominent subsidence features exist near the reclamation site. Subsidence-related fractures were observed in cores from the site, and such fractures may have provided a connection between the shallower and deeper groundwater systems. ?? 1990 Springer-Verlag New York Inc.

  2. Effects of potential surface coal mining on dissolved solids in Otter Creek and in the Otter Creek alluvial aquifer, southeastern Montana

    Science.gov (United States)

    Cannon, M.R.

    1985-01-01

    Otter Creek drains an area of 709 square miles in the coal-rich Powder River structural basin of southeastern Montana. The Knobloch coal beds in the Tongue River Member of the Paleocene Fort Union Formation is a shallow aquifer and a target for future surface mining in the downstream part of the Otter Creek basin. A mass-balance model was used to estimate the effects of potential mining on the dissolved solids concentration in Otter Creek and in the alluvial aquifer in the Otter Creek valley. With extensive mining of the Knobloch coal beds, the annual load of dissolved solids to Otter Creek at Ashland at median streamflow could increase by 2,873 tons, or a 32-percent increase compared to the annual pre-mining load. Increased monthly loads of Otter Creek, at the median streamflow, could range from 15 percent in February to 208 percent in August. The post-mining dissolved solids load to the subirrigated part of the alluvial valley could increase by 71 percent. The median dissolved solids concentration in the subirrigated part of the valley could be 4,430 milligrams per liter, compared to the pre-mining median concentration of 2,590 milligrams per liter. Post-mining loads from the potentially mined landscape were calculated using saturated-paste-extract data from 506 overburdened samples collected from 26 wells and test holes. Post-mining loads to the Otter Creek valley likely would continue at increased rates for hundreds of years after mining. If the actual area of Knobloch coal disturbed by mining were less than that used in the model, post-mining loads to the Otter Creek valley would be proportionally smaller. (USGS)

  3. Investigating uranium distribution in surface sediments and waters: a case study of contamination from the Juniper Uranium Mine, Stanislaus National Forest, CA.

    Science.gov (United States)

    Kayzar, Theresa M; Villa, Adam C; Lobaugh, Megan L; Gaffney, Amy M; Williams, Ross W

    2014-10-01

    The uranium concentrations and isotopic compositions of waters, sediment leachates and sediments from Red Rock Creek in the Stanislaus National Forest of California were measured to investigate the transport of uranium from a point source (the Juniper Uranium Mine) to a natural surface stream environment. The ((234)U)/((238)U) composition of Red Rock Creek is altered downstream of the Juniper Mine. As a result of mine-derived contamination, water ((234)U)/((238)U) ratios are 67% lower than in water upstream of the mine (1.114-1.127 ± 0.009 in the contaminated waters versus 1.676 in the clean branch of the stream), and sediment samples have activity ratios in equilibrium in the clean creek and out of equilibrium in the contaminated creek (1.041-1.102 ± 0.007). Uranium concentrations in water, sediment and sediment leachates are highest downstream of the mine, but decrease rapidly after mixing with the clean branch of the stream. Uranium content and compositions of the contaminated creek headwaters relative to the mine tailings of the Juniper Mine suggest that uranium has been weathered from the mine and deposited in the creek. The distribution of uranium between sediment surfaces (leachable fraction) and bulk sediment suggests that adsorption is a key element of transfer along the creek. In clean creek samples, uranium is concentrated in the sediment residues, whereas in the contaminated creek, uranium is concentrated on the sediment surfaces (∼70-80% of uranium in leachable fraction). Contamination only exceeds the EPA maximum contaminant level (MCL) for drinking water in the sample with the closest proximity to the mine. Isotopic characterization of the uranium in this system coupled with concentration measurements suggest that the current state of contamination in Red Rock Creek is best described by mixing between the clean creek and contaminated upper branch of Red Rock Creek rather than mixing directly with mine sediment. Published by Elsevier Ltd.

  4. 30 CFR 77.1200 - Mine map.

    Science.gov (United States)

    2010-07-01

    ... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Maps § 77.1200 Mine... boundary lines of the active areas of the mine; (c) Contour lines passing through whole number elevations...

  5. Economics of mine water treatment

    OpenAIRE

    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...

  6. CSIR Center for Mining Innovation and the simulated test stope: Paper

    CSIR Research Space (South Africa)

    Teleka, R

    2013-01-01

    Full Text Available The South African mining industry is plagued by accidents ranging from vehicle incidents to roof/rock falls. In the attempt to carry out its mandate of improving the quality of life of South African citizens, the Council for Scientific...

  7. The use of geographical information system (GIS) technology in surface mine reclamation monitoring

    International Nuclear Information System (INIS)

    Dixon, C.

    1999-01-01

    The use of a Geographic Information System (GIS) and related technologies (e.g., Digital cartographic tools, satellite image processing systems) can benefit the planning and monitoring of open-pit mine reclamation activities. PCI Geomatics, in conjunction with Luscar Limited's Line Creek Mine, has developed a GIS-based system designed to store information relevant to planning and assessing reclamation progress. Data that existed in various formats throughout the company, and which had been collected since the mine-planning phase, was integrated into the GIS. The system is used to summarize current reclamation activities and is linked to corporate costing procedures. Monitoring of reclamation activities and quantifying change in the mine area is easily done using the spatial analysis capabilities of the GIS. Assessments of the change in reclamation areas are enhanced by using satellite image data to produce inexpensive and timely information on the land base, and allow the comparison of the health of the vegetation to reclamation areas from year to year. The implemented system substantially reduces the time needed to generate statistics and produce maps for government or internal reports. Also, there are benefits in terms of both cost and effectiveness of reclamation planning

  8. Simulation of actuated synthetic cilia expelling microorganisms from a surface

    Science.gov (United States)

    Shum, Henry; Tripathi, Anurag; Yeomans, Julia; Balazs, Anna

    2013-11-01

    The continual motion of cilia provides a defense against biofouling for a variety of marine organisms. Inspired by this natural solution, we perform numerical simulations to study the interactions between actuated, biomimetic cilia and model microswimmers that are hydrodynamically attracted to bare surfaces and therefore behave similarly to fouling organisms. The 3-dimensional fluid flow is coupled to the motion of the cilia and swimmers using an integrated lattice Boltzmann and immersed boundary method. We show that a sparse array of actuated cilia, through which the organisms are able to swim, is able to robustly expel swimmers. The average residence time of the swimmers in the ciliary layer is reduced if the motion of the cilia generates a net fluid flow, but for relatively fast swimmers, the steric interaction with the moving cilia alone is sufficient to ``knock'' the organisms away from the surface. As the demonstrated mechanisms for antifouling do not rely on specific chemical or physical properties of the surface or swimmer, actuated cilia can potentially protect microfluidic devices, filtration membranes or ship hulls from a wide range of fouling species.

  9. Bioassessment of heavy metals in the surface soil layer of an opencast mine aimed for its rehabilitation.

    Science.gov (United States)

    Ličina, Vlado; Akšić, Milica Fotirić; Tomić, Zorica; Trajković, Ivana; Antić Mladenović, Svetlana; Marjanović, Milena; Rinklebe, Jörg

    2017-01-15

    The contemporary reclamation method in an opencast coal mine closure comprises the use of the preserved surface soil layer (SSL) before mining, and can be directly returned to the areas being rehabilitated. The present study emphasizes a risk in the use of such a SSL in mine rehabilitation due to the possible excessive amount of heavy metals which usually derives from a metal-rich sediment or fluvial character of overburden material. This indication was approved by the bioassessment of cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), lead (Pb), nickel (Ni), and zinc (Zn) in root and aerial parts of maize (Zea mays), alfalfa (Medicago sativa), sweet clover (Melilotus officinalis), wheat (Triticum aestivum), barley (Hordeum sativum), white clover (Trifolium repens), pasture (Poales sp.), tomato (Solanum lycopersicum), potato (Solanum tuberosum) and carrot (Daucus carota) grown on SSL in the opencast mine area. The fluvial layers of the investigated mine SSL revealed the excessive existence of Ni and Cr, probably of geogenic origin, according to the X-ray diffraction (XRD) which detected Ni- and Cr-bearing minerals in soil fractions. In addition, the highest residual fraction of these two heavy metals, obtained by sequential extraction analyses, together with all other tested soil parameters, supported this assumption. Nevertheless, the accumulations of Cr in tomato fruit (2.93 mg kg -1 ), potato tuber (5.89 mg kg -1 ) and carrot root (7.35 mg kg -1 ) grown on the investigated SSL were found to exceed a critical level of this element for human nutrition. However, despite the evident excess of Ni in the investigated SSL, a similar trend was not found in edible part of plants. The transfer and mobility of the investigated metals was evaluated using the accumulation factor (AF < 1.0) where the root were the preferential organ for the storage of heavy metals. This investigation could bring an important input for its acceptability of use in soil restoration

  10. Simulation of the hydrogeologic effects of oil-shale mining on the neighbouring wetland water balance: case study in north-eastern Estonia

    Science.gov (United States)

    Marandi, Andres; Karro, Enn; Polikarpus, Maile; Jõeleht, Argo; Kohv, Marko; Hang, Tiit; Hiiemaa, Helen

    2013-11-01

    The water balance of wetlands plays an integral role in their function. Developments adjacent to wetlands can affect their water balance through impacts on groundwater flow and increased discharge in the area, and they can cause lowering of the wetland water table. A 430 km2 area was selected for groundwater modelling to asses the effect of underground mining on the water balance of wetlands in north-eastern Estonia. A nature conservation area (encompassing Selisoo bog) is within 3 km of an underground oil-shale mine. Two future mining scenarios with different areal extents of mining were modeled and compared to the present situation. Results show that the vertical hydraulic conductivity of the subsurface is of critical importance to potential wetland dewatering as a result of mining. Significant impact on the Selisoo bog water balance will be caused by the approaching mine but there will be only minor additional impacts from mining directly below the bog. The major impact will arise before that stage, when the underground mine extension reaches the border of the nature conservation area; since the restriction of activities in this area relates to the ground surface, the conservation area’s border is not sufficiently protective in relation to underground development.

  11. Determination of granite rock massif weathering and cracking of surface layers in the oldest parts of medieval mine depending on used mining method

    Czech Academy of Sciences Publication Activity Database

    Lednická, Markéta; Kaláb, Zdeněk

    2016-01-01

    Roč. 61, č. 2 (2016), s. 381-395 ISSN 0860-7001 R&D Projects: GA MŠk(CZ) LO1406; GA MŠk ED2.1.00/03.0082 Institutional support: RVO:68145535 Keywords : Jeroným Mine * non-destructive testing * granite Subject RIV: DH - Mining, incl. Coal Mining Impact factor: 0.550, year: 2016 http://archiwum.img-pan.krakow.pl/index.php/AMS/article/view/785/692

  12. Sampling and sample handling procedures for priority pollutants in surface coal mining wastewaters. [Detailed list to be analyzed for

    Energy Technology Data Exchange (ETDEWEB)

    Hayden, R. S.; Johnson, D. O.; Henricks, J. D.

    1979-03-01

    The report describes the procedures used by Argonne National Laboratory to sample surface coal mine effluents in order to obtain field and laboratory data on 110 organic compounds or classes of compounds and 14 metals and minerals that are known as priority pollutants, plus 5-day biochemical oxygen demand (BOD/sub 5/), total organic carbon (TOC), chemical oxygen demand (COD), total dissolved solids (TDS), and total suspended solids (TSS). Included are directions for preparation of sampling containers and equipment, methods of sampling and sample preservation, and field and laboratory protocols, including chain-of-custody procedures. Actual analytical procedures are not described, but their sources are referenced.

  13. Natural radionuclides in fish species from surface water of Bagjata and Banduhurang uranium mining areas, East Singhbhum, Jharkhand, India.

    Science.gov (United States)

    Giri, Soma; Singh, Gurdeep; Jha, V N; Tripathi, R M

    2010-11-01

    To study the natural radionuclides in the freshwater fish samples around the uranium mining areas of Bagjata and Banduhurang, East Singhbhum, Jharkhand, India. The naturally occurring radioisotopes of uranium, U(nat), consisting of (234)U, (235)U and (238)U; (226)Ra, (230)Th and (210)Po were analysed in the fish samples from the surface water of Bagjata and Banduhurang mining areas after acid digestion. The ingestion dose, concentration factor and excess lifetime cancer risk of the radionuclides were estimated. The geometric mean activity of U(nat), (226)Ra, (230)Th and (210)Po in the fish samples was found to be 0.05, 0.19, 0.29 and 0.95 Bq kg(-1)(fresh) (Becquerel per kilogram fresh fish), respectively, in the Bagjata mining area, while for Banduhurang mining area it was estimated to be 0.08, 0.41, 0.22 and 2.48 Bq kg(-1)(fresh), respectively. The ingestion dose was computed to be 1.88 and 4.16 μSvY(-1), respectively, for both the areas which is much below the 1 mSv limit set in the new International Commission on Radiological Protection (ICRP) recommendations. The estimation of the Concentration Factors (CF) reveal that the CF from water is greater than 1 l/kg(-1)in most of the cases while from sediment CF is less than 1. The excess individual lifetime cancer risk due to the consumption of fish was calculated to be 2.53 × 10(-5) and 6.48 × 10(-5), respectively, for Bagjata and Banduhurang areas, which is within the acceptable excess individual lifetime cancer risk value of 1 × 10(-4). The study confirms that current levels of radioactivity do not pose a significant radiological risk to freshwater fish consumers.

  14. Applications of granular-dynamics numerical simulations to asteroid surfaces

    Science.gov (United States)

    Richardson, D. C.; Michel, P.; Schwartz, S. R.; Yu, Y.; Ballouz, R.-L.; Matsumura, S.

    2014-07-01

    Spacecraft images and indirect observations including thermal inertia measurements indicate most small bodies have surface regolith. Evidence of granular flow is also apparent in the images. This material motion occurs in very low gravity, therefore in a totally different gravitational environment than on the Earth. Upcoming sample-return missions to small bodies, and possible future manned missions, will involve interaction with the surface regolith, so it is important to develop tools to predict the surface response. We have added new capabilities to the N-body gravity tree code pkdgrav [1,2] that permit the simulation of granular dynamics, including multi-contact physics and friction forces, using the soft-sphere discrete-element method [3]. The numerical approach has been validated through comparison with laboratory experiments (e.g., [3,4]). (1) We carried out impacts into granular materials using different projectile shapes under Earth's gravity [5] and compared the results to laboratory experiments [6] in support of JAXA's Hayabusa 2 asteroid sample-return mission. We tested different projectile shapes and confirmed that the 90-degree cone was the most efficient at excavating mass when impacting 5-mm-diameter glass beads. Results are sensitive to the normal coefficient of restitution and the coefficient of static friction. Preliminary experiments in micro-gravity for similar impact conditions show both the amount of ejected mass and the timescale of the impact process increase, as expected. (2) It has been found (e.g., [7,8]) that ''fresh'' (unreddened) Q-class asteroids have a high probability of recent planetary encounters (˜1 Myr; also see [9]), suggesting that surface refreshening may have occurred due to tidal effects. As an application of the potential effect of tidal interactions, we carried out simulations of Apophis' predicted 2029 encounter with the Earth to see whether regolith motion might occur, using a range of plausible material parameters

  15. Hydrogeochemical processes governing the origin, transport and fate of major and trace elements from mine wastes and mineralized rock to surface waters

    Science.gov (United States)

    Nordstrom, D. Kirk

    2011-01-01

    The formation of acid mine drainage from metals extraction or natural acid rock drainage and its mixing with surface waters is a complex process that depends on petrology and mineralogy, structural geology, geomorphology, surface-water hydrology, hydrogeology, climatology, microbiology, chemistry, and mining and mineral processing history. The concentrations of metals, metalloids, acidity, alkalinity, Cl-, F- and SO42- found in receiving streams, rivers, and lakes are affected by all of these factors and their interactions. Remediation of mine sites is an engineering concern but to design a remediation plan without understanding the hydrogeochemical processes of contaminant mobilization can lead to ineffective and excessively costly remediation. Furthermore, remediation needs a goal commensurate with natural background conditions rather than water-quality standards that might bear little relation to conditions of a highly mineralized terrain. This paper reviews hydrogeochemical generalizations, primarily from US Geological Survey research, that enhance our understanding of the origin, transport, and fate of contaminants released from mined and mineralized areas.

  16. Application of MIKE SHE to study the impact of coal mining on river runoff in Gujiao mining area, Shanxi, China.

    Science.gov (United States)

    Ping, Jianhua; Yan, Shiyan; Gu, Pan; Wu, Zening; Hu, Caihong

    2017-01-01

    Coal mining is one of the core industries that contribute to the economic development of a country but deteriorate the environment. Being the primary source of energy, coal has become essential to meet the energy demand of a country. It is excavated by both opencast and underground mining methods and affects the environment, especially hydrological cycle, by discharging huge amounts of mine water. Natural hydrological processes have been well known to be vulnerable to human activities, especially large scale mining activities, which inevitably generate surface cracks and subsidence. It is therefore valuable to assess the impact of mining on river runoff for the sustainable development of regional economy. In this paper, the impact of coal mining on river runoff is assessed in one of the national key coal mining sites, Gujiao mining area, Shanxi Province, China. The characteristics of water cycle are described, the similarities and differences of runoff formation are analyzed in both coal mining and pre-mining periods. The integrated distributed hydrological model named MIKE SHE is employed to simulate and evaluate the influence of coal mining on river runoff. The study shows that mining one ton of raw coal leads to the reduction of river runoff by 2.87 m3 between 1981 and 2008, of which the surface runoff decreases by 0.24 m3 and the baseflow by 2.63 m3. The reduction degree of river runoff for mining one ton of raw coal shows an increasing trend over years. The current study also reveals that large scale coal mining initiates the formation of surface cracks and subsidence, which intercepts overland flow and enhances precipitation infiltration. Together with mine drainage, the natural hydrological processes and the stream flows have been altered and the river run off has been greatly reduced.

  17. Application of MIKE SHE to study the impact of coal mining on river runoff in Gujiao mining area, Shanxi, China.

    Directory of Open Access Journals (Sweden)

    Jianhua Ping

    Full Text Available Coal mining is one of the core industries that contribute to the economic development of a country but deteriorate the environment. Being the primary source of energy, coal has become essential to meet the energy demand of a country. It is excavated by both opencast and underground mining methods and affects the environment, especially hydrological cycle, by discharging huge amounts of mine water. Natural hydrological processes have been well known to be vulnerable to human activities, especially large scale mining activities, which inevitably generate surface cracks and subsidence. It is therefore valuable to assess the impact of mining on river runoff for the sustainable development of regional economy. In this paper, the impact of coal mining on river runoff is assessed in one of the national key coal mining sites, Gujiao mining area, Shanxi Province, China. The characteristics of water cycle are described, the similarities and differences of runoff formation are analyzed in both coal mining and pre-mining periods. The integrated distributed hydrological model named MIKE SHE is employed to simulate and evaluate the influence of coal mining on river runoff. The study shows that mining one ton of raw coal leads to the reduction of river runoff by 2.87 m3 between 1981 and 2008, of which the surface runoff decreases by 0.24 m3 and the baseflow by 2.63 m3. The reduction degree of river runoff for mining one ton of raw coal shows an increasing trend over years. The current study also reveals that large scale coal mining initiates the formation of surface cracks and subsidence, which intercepts overland flow and enhances precipitation infiltration. Together with mine drainage, the natural hydrological processes and the stream flows have been altered and the river run off has been greatly reduced.

  18. Application of MIKE SHE to study the impact of coal mining on river runoff in Gujiao mining area, Shanxi, China

    Science.gov (United States)

    Ping, Jianhua; Yan, Shiyan; Gu, Pan; Wu, Zening; Hu, Caihong

    2017-01-01

    Coal mining is one of the core industries that contribute to the economic development of a country but deteriorate the environment. Being the primary source of energy, coal has become essential to meet the energy demand of a country. It is excavated by both opencast and underground mining methods and affects the environment, especially hydrological cycle, by discharging huge amounts of mine water. Natural hydrological processes have been well known to be vulnerable to human activities, especially large scale mining activities, which inevitably generate surface cracks and subsidence. It is therefore valuable to assess the impact of mining on river runoff for the sustainable development of regional economy. In this paper, the impact of coal mining on river runoff is assessed in one of the national key coal mining sites, Gujiao mining area, Shanxi Province, China. The characteristics of water cycle are described, the similarities and differences of runoff formation are analyzed in both coal mining and pre-mining periods. The integrated distributed hydrological model named MIKE SHE is employed to simulate and evaluate the influence of coal mining on river runoff. The study shows that mining one ton of raw coal leads to the reduction of river runoff by 2.87 m3 between 1981 and 2008, of which the surface runoff decreases by 0.24 m3 and the baseflow by 2.63 m3. The reduction degree of river runoff for mining one ton of raw coal shows an increasing trend over years. The current study also reveals that large scale coal mining initiates the formation of surface cracks and subsidence, which intercepts overland flow and enhances precipitation infiltration. Together with mine drainage, the natural hydrological processes and the stream flows have been altered and the river run off has been greatly reduced. PMID:29267313

  19. Assessment of Radioactive Materials and Heavy Metals in the Surface Soil around the Bayanwula Prospective Uranium Mining Area in China.

    Science.gov (United States)

    Bai, Haribala; Hu, Bitao; Wang, Chengguo; Bao, Shanhu; Sai, Gerilemandahu; Xu, Xiao; Zhang, Shuai; Li, Yuhong

    2017-03-14

    The present work is the first systematic and large scale study on radioactive materials and heavy metals in surface soil around the Bayanwula prospective uranium mining area in China. In this work, both natural and anthropogenic radionuclides and heavy metals in 48 surface soil samples were analyzed using High Purity Germanium (HPGe) γ spectrometry and inductively coupled plasma-mass spectrometry (ICP-MS). The obtained mean activity concentrations of 238 U, 226 Ra, 232 Th, 40 K, and 137 Cs were 25.81 ± 9.58, 24.85 ± 2.77, 29.40 ± 3.14, 923.0 ± 47.2, and 5.64 ± 4.56 Bq/kg, respectively. The estimated average absorbed dose rate and annual effective dose rate were 76.7 ± 3.1 nGy/h and 83.1 ± 3.8 μ Sv, respectively. The radium equivalent activity, external hazard index, and internal hazard index were also calculated, and their mean values were within the acceptable limits. The estimated lifetime cancer risk was 3.2 × 10 -4 /Sv. The heavy metal contents of Cr, Ni, Cu, Zn, As, Cd, and Pb from the surface soil samples were measured and their health risks were then assessed. The concentrations of all heavy metals were much lower than the average backgrounds in China except for lead which was about three times higher than that of China's mean. The non-cancer and cancer risks from the heavy metals were estimated, which are all within the acceptable ranges. In addition, the correlations between the radionuclides and the heavy metals in surface soil samples were determined by the Pearson linear coefficient. Strong positive correlations between radionuclides and the heavy metals at the 0.01 significance level were found. In conclusion, the contents of radionuclides and heavy metals in surface soil around the Bayanwula prospective uranium mining area are at a normal level.

  20. Adhesion characterization of tungsten mine waste geopolymeric binder. Influence of OPC concrete substance surface treatment

    OpenAIRE

    Torgal, Fernando Pacheco; Gomes, J. P. Castro; Jalali, Said

    2008-01-01

    Tungsten mine waste mud (TMWM) was investigated for its potential use as repair material of ordinary portland cement (OPC) concrete. Bond strength between OPC concrete substrate and three repair materials was analysed. TMWM geopolymeric binder and two commercial repair products were used as repair materials. Bond strength behaviour was assessed from slant shear tests. A total of 128 slant shear specimens were made in order to evaluate bond strength at 1, 3, 7 and 28 days curing. Four ki...

  1. Distribution of natural radionuclides in surface soils in the vicinity of abandoned uranium mines in Serbia.

    Science.gov (United States)

    Momčilović, Milan; Kovačević, Jovan; Tanić, Milan; Dorđević, Milan; Bačić, Goran; Dragović, Snežana

    2013-02-01

    The activity concentrations of natural radionuclides in soils from the area affected by uranium mining at Stara Planina Mountain in Serbia were studied and compared with the results obtained from an area with no mining activities (background area). In the affected area, the activity concentrations ranged from 1.75 to 19.2 mg kg(-1) for uranium and from 1.57 to 26.9 mg kg(-1) for thorium which is several-fold higher than those in the background area. The Th/U, K/U, and K/Th activity ratios were also determined and compared with data from similar studies worldwide. External gamma dose rate in the air due to uranium, thorium, and potassium at 1 m above ground level in the area affected by uranium mining was found to be 91.3 nGy h(-1), i.e., about two-fold higher than that in background area. The results of this preliminary study indicate the importance of radiological evaluation of the area and implementation of remedial measures in order to prevent further dispersion of radionuclides in the environment.

  2. Grasshopper sparrow reproductive success and habitat use on reclaimed surface mines varies by age of reclamation

    Science.gov (United States)

    Wood, Petra; Ammer, Frank K.

    2015-01-01

    We studied 3 mountaintop mining–valley fill (MTMVF) complexes in southern West Virginia, USA to examine grasshopper sparrow (Ammodramus savannarum pratensis) demographic response to different age classes of mine land reclamation. For 71 nests monitored during the 2001–2002 breeding seasons, overall nest success (36%) was within the range of nest success rates previously reported for this species, but it was highest on more recently reclaimed sites (56%). Nest density and clutch size did not differ (P > 0.30) among reclamation age classes, whereas number of fledglings was greater (P = 0.01) on more recently reclaimed sites. We measured vegetation variables at 70 nest subplots and at 96 systematic subplots to compare nest vegetation with vegetation available on the plots. We found that nests occurred in areas with more bare ground near the nest, greater vegetation height–density surrounding the nest site, lower grass height, and fewer woody stems, similar to previous studies. As postreclamation age increased, vegetation height–density and maximum grass height increased, and sericea (Lespedeza cuneata) became more dominant. Nest success declined with increasing vegetation height–density at the nest. The grasslands available on these reclaimed mine complexes are of sufficient quality to support breeding populations of grasshopper sparrows, but nest success decreased on the older reclaimed areas. Without active management, grasslands on reclaimed MTMVF mines become less suitable for nesting grasshopper sparrows about 10 years after reclamation.

  3. First-Year Vitality of Reforestation Plantings in Response to Herbivore Exclusion on Reclaimed Appalachian Surface-Mined Land

    Directory of Open Access Journals (Sweden)

    Zachary J. Hackworth

    2018-04-01

    Full Text Available Conventional Appalachian surface-mine reclamation techniques repress natural forest regeneration, and tree plantings are often necessary for reforestation. Reclaimed Appalachian surface mines harbor a suite of mammal herbivores that forage on recently planted seedlings. Anecdotal reports across Appalachia have implicated herbivory in the hindrance and failure of reforestation efforts, yet empirical evaluation of herbivory impacts on planted seedling vitality in this region remains relatively uninitiated. First growing-season survival, height growth, and mammal herbivory damage of black locust (Robinia pseudoacacia L., shortleaf pine (Pinus echinata Mill., and white oak (Quercus alba L. are presented in response to varying intensities of herbivore exclusion. Seedling survival was generally high, and height growth was positive for all species. The highest herbivory incidence of all tree species was observed in treatments offering no herbivore exclusion. While seedling protectors lowered herbivory incidence compared with no exclusion, full exclusion treatments resulted in the greatest reduction of herbivore damage. Although herbivory from rabbits, small mammals, and domestic animals was observed, cervids (deer and elk were responsible for 95.8% of all damaged seedlings. This study indicates that cervids forage heavily on planted seedlings during the first growing-season, but exclusion is effective at reducing herbivory.

  4. Surface deformation in areas of abandoned mining: a case study of InSAR applied in the Northumberland region of the UK

    Science.gov (United States)

    Mccormack, Harry; Bateson, Luke; Banton, Carl; Holley, Rachel; Lawrence, David; Cigna, Francesca; Watson, Ian; Burren, Richard

    2013-04-01

    The United Kingdom has a rich history of coal mining probably dating back to Roman times, and this was a driving force behind the industrial revolution. Although the amount of mining has decreased significantly in recent years, the effects of mining on ground stability are widespread, complex and under-monitored. The Coal Authority is responsible for protecting the public and environment in coal mining areas. Particularly they are responsible for administering coal mining subsidence damage claims and preventing problems due to rising groundwater in old mining areas. Drawing on the expertise of Fugro NPA (FNPA) and the British Geological Survey (BGS), the aim of this project was to show how a wide-area ground stability dataset with associated geological interpretation could help the Coal Authority better administer their subsidence claims and groundwater management. This work was performed within the Terrafirma project. The study area chosen was the Northumberland and Durham coalfield where the last active mine closed in 2005. More than 20 seams have been mined and as depths increased this led to the need to pump water to prevent the mines from flooding. As the mines shut down the pumping stopped, causing the water level to rise and recover. Using interferometric synthetic aperture radar (InSAR) techniques FNPA produced a surface deformation dataset which was interpreted by BGS to add value in the form of geological interpretation. The dataset covers two epochs; 1995-2000 and 2002-2008. During the earlier epoch eight to nine 'hotspots' of subsidence were identified, mainly in the south of the study area. All but one of the subsidence areas shows a strong spatial correlation with areas of past mining. However there is a discrepancy in the timing of InSAR deformations and the timing of subsidence that would be expected given the type of workings. It is suspected that the spatial and temporal pattern of deformation relates not only to material extraction but also to

  5. Water-quality data for two surface coal mines reclaimed with alkaline waste or urban sewage sludge, Clarion County, Pennsylvania, May 1983 through November 1989

    Science.gov (United States)

    Dugas, D.L.; Cravotta, C.A.; Saad, D.A.

    1993-01-01

    Water-quality and other hydrologic data for two surface coal mines in Clarion County, Pa., were collected during 1983-89 as part of studies conducted by the U.S. Geological Survey in cooperation with the Pennsylvania Department of Environmental Resources. Water samples were collected from streams, seeps, monitor wells, and lysimeters on a monthly basis to evaluate changes in water quality resulting from the addition of alkaline waste or urban sewage sludge to the reclaimed mine-spoil surface. The mines are about 3.5 miles apart and were mined for bituminous coal of the upper and lower Clarion seams of the Allegheny Group of Pennsylvanian age. The coal had high sulfur (greater than 2 weight percent) concentrations. Acidic mine drainage is present at both mines. At one mine, about 8 years after mining was completed, large quantities (greater than 400 tons per acre) of alkaline waste consisting of limestone and lime-kiln flue dust were applied on two 2.5-acre plots within the 65-acre mine area. Water-quality data for the alkaline-addition plots and surrounding area were collected for 1 year before and 3 years after application of the alkaline additives (May 1983-July 1987). Data collected for the alkaline-addition study include ground-water level, surface-water discharge rate, temperature, specific conductance, pH, and concentrations of alkalinity, acidity, sulfate, iron (total and ferrous), manganese, aluminum, calcium, and magnesium. At the other mine, about 3.5 years after mining was completed, urban sewage sludge was applied over 60 acres within the 150-acre mine area. Waterquality data for the sludge-addition study were collected for 3.5 years after the application of the sludge (June 1986-December 1989). Data collected for the sludge-addition study include the above constituents plus dissolved oxygen, redox potential (Eh), and concentrations of dissolved solids, phosphorus, nitrogen species, sulfide, chloride, silica, sodium, potassium, cyanide, arsenic, barium

  6. Wideband Detection and Classification of Mines in a Simulated ship Hull Scenario

    Science.gov (United States)

    2007-12-01

    caoutchouc et de billes d’acier, sur une feuille de fibre de verre, par la suite suspendue dans le bassin d’étalonnage acoustique de RDDC Atlantique...contenues dans une bande large — possiblement de concert avec un sonar imageant — comme outil acoustique pour découvrir des mines sur la coque d’un navire...d’acier, sur une feuille de fibre de verre, par la suite suspendue dans le bassin d’étalonnage acoustique de RDDC Atlantique. Ce montage a été ensuite

  7. Monitoring the impact of simulated deep-sea mining in Central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Sharma, R.; Nath, B.N.; Jaisankar, S.

    Ocean (Foell et al. 1990; Trueblood 1993; Fukushima 1995; Tkatchenko et al. 1996). Sediment transport during deep-sea disturbances, natural or artificial, not only has immediate effects, but also long term impacts, and the restoration is a very com- plex... for designing and undertaking a deep-sea mining operation. This study gives an overview on the immediate effects and long-term (44 months later) restoration of the deep-sea floor environment at the INDEX site in the Central Indian Basin. Work Done Under...

  8. Evaluation of surface water quality in aquatic bodies under the influence of uranium mining (MG, Brazil).

    Science.gov (United States)

    Rodgher, Suzelei; de Azevedo, Heliana; Ferrari, Carla Rolim; Roque, Cláudio Vítor; Ronqui, Leilane Barbosa; de Campos, Michelle Burato; Nascimento, Marcos Roberto Lopes

    2013-03-01

    The quality of the water in a uranium-ore-mining area located in Caldas (Minas Gerais State, Brazil) and in a reservoir (Antas reservoir) that receives the neutralized acid solution leaching from the waste heaps generated by uranium mining was investigated. The samples were collected during four periods (October 2008, January, April and July 2009) from six sampling stations. Physical and chemical analyses were performed on the water samples, and the data obtained were compared with those of the Brazilian Environmental Standards and WHO standard. The water samples obtained from waste rock piles showed high uranium concentrations (5.62 mg L(-1)), high manganese values (75 mg L(-1)) and low average pH values (3.4). The evaluation of the water quality at the point considered the limit between the Ore Treatment Unit of the Brazilian Nuclear Industries and the environment (Consulta Creek) indicated contamination by fluoride, manganese, uranium and zinc. The Antas reservoir showed seasonal variations in water quality, with mean concentrations for fluoride (0.50 mg L(-1)), sulfate (16 mg L(-1)) and hardness (20 mg L(-1)) which were low in January, evidencing the effect of rainwater flowing into the system. The concentrations for fluoride, sulfate and manganese were close or above to the limits established by current legislation at the point where the treated mining effluent was discharged and downstream from this point. This study demonstrated that the effluent discharged by the UTM affected the quality of the water in the Antas reservoir, and thus the treatments currently used for effluent need to be reviewed.

  9. Landscape management in an area affected by surface brown coal mining

    Science.gov (United States)

    Vráblíková, J.; Wildová, E.; Vráblík, P.; Blažková, M.

    2017-10-01

    The contribution summarizes results of a project concentrated on landscape management of an area affected by brown coal mining located in northern Bohemia (The Most basin) focusing on restoration and reclamation processes. It describes in particular the shares of individual types of reclamations in the area of interest. A strategic document that also supports landscape restoration in anthropogenically burdened regions was written within the project called “Restart” and the second part of the contribution is focused on its chapters which address this issue.

  10. Assessment of the Pollutants in Soils and Surface Waters Around Gümüşköy Silver Mine (Kütahya, Turkey).

    Science.gov (United States)

    Arslan, Şebnem; Çelik, Mehmet

    2015-10-01

    Heavy metal concentrations in surface water and soil samples around Gümüşköy Silver Mine, located in Köprüören Basin, were determined to evaluate the anthropogenic level of contamination due to mining activities. The mean concentrations of As, Pb, Sb and Cd in 12 soil samples came out to be 1193, 844, 66 and 19 ppm, respectively. Soil pollution assessment was carried out by using geoaccumulation index (Igeo), enrichment factor (EF) and pollution index (PI). Igeo, EF and PI suggest anthropogenic pollution of As, Pb, Sb and Zn in the areas where there is leakage of these heavy metals from the waste pools of the silver mine facility. Water samples collected from the surface waters also have elevated concentrations of these heavy metals. The contaminants are most probably transported by surface waters in the rainy season.

  11. Simulation and Optimization of Silicon Solar Cell Back Surface Field

    Directory of Open Access Journals (Sweden)

    Souad TOBBECHE

    2015-11-01

    Full Text Available In this paper, TCAD Silvaco (Technology Computer Aided Design software has been used to study the Back Surface Field (BSF effect of a p+ silicon layer for a n+pp+ silicon solar cell. To study this effect, the J-V characteristics and the external quantum efficiency (EQE are simulated under AM 1.5 illumination for two types of cells. The first solar cell is without BSF (n+p structure while the second one is with BSF (n+pp+ structure. The creation of the BSF on the rear face of the cell results in efficiency h of up to 16.06% with a short-circuit current density Jsc = 30.54 mA/cm2, an open-circuit voltage Voc = 0.631 V, a fill factor FF = 0.832 and a clear improvement of the spectral response obtained in the long wavelengths range. An electric field and a barrier of potential are created by the BSF and located at the junction p+/p with a maximum of 5800 V/cm and 0.15 V, respectively. The optimization of the BSF layer shows that the cell performance improves with the p+ thickness between 0.35 – 0.39 µm, the p+ doping dose is about 2 × 1014 cm-2, the maximum efficiency up to 16.19 %. The cell efficiency is more sensitive to the value of the back surface recombination velocity above a value of 103 cm/s in n+p than n+pp+ solar cell.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.9565

  12. Barium concentrations and speciation in surface waters collected from an active barium mining area in Guizhou Province, southwestern China.

    Science.gov (United States)

    Lu, Qinhui; Xu, Xiaohang; Xu, Zhidong; Liang, Longchao; Shang, Lihai; Xiao, Dean; Zhang, Sensen; Jiang, Yuping; Qiu, Guangle

    2018-03-01

    Barium (Ba) is a toxic element and can cause serious health effects. Humans have experienced increased exposure to Ba due to its intensive usage in industrial areas and daily life. Anthropogenic activities of Ba mining and the manufacture of Ba containing products introduce the element into surrounding areas, posing environmental concerns. Concentrations of total Ba (TBa) and dissolved Ba (DBa) in water samples collected from active Ba mines in Tianzhu, east Guizhou Province, southwestern China were measured to show the regional dispersion of Ba contamination. Aqueous Ba species in water were calculated using the PHREEQC program. The results showed that TBa and DBa concentrations ranged from 6.7 to 483.1 μg/L and from 7.5 to 222.7 μg/L, respectively. TBa concentrations presented a high average value of 126.6 μg/L and greatly exceeded the reported common value of 10 μg/L Ba in surface water set by the Ministry of Environment Protection of China. PHREEQC results indicated that Ba species in water were present as Ba 2+ , BaSO 4 , BaHCO 3 , BaCO 3 , and BaOH + . The distribution of Ba species in water is controlled by pH and total organic carbon (TOC), and the lower pH (pH < 7) the higher the dissolved fractions. The log K d values (K d , dissolved-particulate distribution coefficients) varied from 2.41 to 6.32. Significant correlations were observed among Ba 2+ and K + , Na + , Cl - , NO 3 - , with Pearson correlation coefficients of 0.425, 0.531, 0.853, 0.612, and 0.329, respectively (p < 0.01). Elevated Ba concentrations in water indicated that the Ba contamination and its distribution pattern in local aquatic ecosystems are derived from Ba mining sites in the Tianzhu area.

  13. A facile method for simulating randomly rough membrane surface associated with interface behaviors

    Science.gov (United States)

    Qu, Xiaolu; Cai, Xiang; Zhang, Meijia; Lin, Hongjun; Leihong, Zhao; Liao, Bao-Qiang

    2018-01-01

    Modeling rough surfaces has emerged as a distinct discipline of considerable research interest in interface behaviors including membrane fouling. In this paper, a facile method was proposed to simulate rough membrane surface morphology. Natural membrane surface was found to be randomly rough, and its height distribution obeys Gaussian distribution. A new method which combines spectrum method, Gaussian distribution and Fourier transform technique was deduced. Simulation of the rough membrane surface showed high similarity in terms of statistical roughness and height distribution between the simulated surface and the real membrane surface, indicating feasibility of the new method. It was found that, correlation length (l) and the number of superposed ridges (N) are key parameters affecting the simulated membrane surface morphology. This new method has evident advantages over conventional modeling methods The proposed method for randomly rough membrane surface modeling could be potentially used to quantify the interfacial interactions between two rough surfaces, giving implications for membrane fouling mitigation.

  14. MoleculaRnetworks: an integrated graph theoretic and data mining tool to explore solvent organization in molecular simulation.

    Science.gov (United States)

    Mooney, Barbara Logan; Corrales, L René; Clark, Aurora E

    2012-03-30

    This work discusses scripts for processing molecular simulations data written using the software package R: A Language and Environment for Statistical Computing. These scripts, named moleculaRnetworks, are intended for the geometric and solvent network analysis of aqueous solutes and can be extended to other H-bonded solvents. New algorithms, several of which are based on graph theory, that interrogate the solvent environment about a solute are presented and described. This includes a novel method for identifying the geometric shape adopted by the solvent in the immediate vicinity of the solute and an exploratory approach for describing H-bonding, both based on the PageRank algorithm of Google search fame. The moleculaRnetworks codes include a preprocessor, which distills simulation trajectories into physicochemical data arrays, and an interactive analysis script that enables statistical, trend, and correlation analysis, and other data mining. The goal of these scripts is to increase access to the wealth of structural and dynamical information that can be obtained from molecular simulations. Copyright © 2012 Wiley Periodicals, Inc.

  15. Three-Dimensional Model of a Muscle and Simulation of its Surface EMG

    National Research Council Canada - National Science Library

    Schnetzer, M

    2001-01-01

    ...) and a simulation of its surface EMG. The simulations are part of a larger model including in addition the input system to the motoneuronal pool, the motoneuronal pool itself and the force generating mechanism...

  16. Acid mine drainage simulated leaching behavior of goethite and cobalt substituted goethite

    Science.gov (United States)

    Penprase, S. B.; Kimball, B. E.

    2015-12-01

    Though most modern day mining aims to eliminate the seepage of acid mine drainage (AMD) to the local watershed, historical mines regularly receive little to no remediation, and often release acidic, metal-rich drainage and particles to the environment. Treatment of AMD often includes neutralizing pH to facilitate the precipitation of Fe-oxides and dissolved trace metals, thereby forming Trace Metal Substituted (TMS) forms of known minerals, such as goethite (α-FeOOH). The stability of TMS precipitates is not fully understood. As a result, we conducted a 20 day leach experiment using laboratory synthesized pure (Gt) and cobalt-substituted (CoGt) goethites with a dilute ultrapure HCl solution (pH = 3.61) at T = 23.3±2.5ºC. Leached solids were characterized using X-ray diffraction (XRD) and scanning electron microscopy paired with energy dispersive spectroscopy (SEM-EDS). Leach solutions were sampled for pH and conductivity, and dissolved chemistry was determined with Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). Preliminary results indicate Gt and CoGt filtered leach solutions experienced constant pH (Gt = 3.9 ± 0.1, CoGt = 6.8 ± 0.2) and conductivity (Gt = 69 ± 6.6 μS/cm, CoGt = 81 ± 16 μS/cm) for t = 0-20 days. Micro-focused XRD results indicate that leached solids did not change in mineralogy throughout the experiment, and SEM images show minor disintegration along mineral grain edges, but little overall change in shape. Preliminary ICP-MS results show lower dissolved Fe concentrations for CoGt (1.1 ± 1.1 ppb) compared to Gt (17 ± 8.9 ppb) over time. Dissolved Co concentrations ranged from 560 - 830 ppb and increased over time. Compared to leaching of pure Gt, leaching of CoGt generated significantly higher pH, slightly higher conductivity, and significantly less dissolved Fe. During the CoGt leach, Co was preferentially leached over Fe. The differences in leaching behavior between pure and TMS goethite in the laboratory have implications for

  17. Reliable low precision simulations in land surface models

    Science.gov (United States)

    Dawson, Andrew; Düben, Peter D.; MacLeod, David A.; Palmer, Tim N.

    2017-12-01

    Weather and climate models must continue to increase in both resolution and complexity in order that forecasts become more accurate and reliable. Moving to lower numerical precision may be an essential tool for coping with the demand for ever increasing model complexity in addition to increasing computing resources. However, there have been some concerns in the weather and climate modelling community over the suitability of lower precision for climate models, particularly for representing processes that change very slowly over long time-scales. These processes are difficult to represent using low precision due to time increments being systematically rounded to zero. Idealised simulations are used to demonstrate that a model of deep soil heat diffusion that fails when run in single precision can be modified to work correctly using low precision, by splitting up the model into a small higher precision part and a low precision part. This strategy retains the computational benefits of reduced precision whilst preserving accuracy. This same technique is also applied to a full complexity land surface model, resulting in rounding errors that are significantly smaller than initial condition and parameter uncertainties. Although lower precision will present some problems for the weather and climate modelling community, many of the problems can likely be overcome using a straightforward and physically motivated application of reduced precision.

  18. Mountaintop mining consequences

    Science.gov (United States)

    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...

  19. Modeling and simulation as a tool to support decision making and change of scenery for improved productivity: the case of mining

    Directory of Open Access Journals (Sweden)

    Jackson Kêntelly Marculino de Souza

    2017-09-01

    Full Text Available Computer modeling and discrete event simulation of industrial processes have gained a prominent role for the analysis of capacity and management improvement, which generate competitive advantages for organizations. Although some studies involving simulation in the mining area were found, countless application opportunities in mining subareas to assist managers in decision-making were encountered. This work shows the process of loading and transport of minerals in an open pit mine in order to generate a simulation model that best represents the system to propose improvements in the composition of the load and transport equipment employed in the mine. The model was developed inthe discrete event simulation software, Arena, and validated to allow for the creation of alternative scenarios to achieve operational improvements. The best alternative that resulted from the scenario stipulated the replacement of a hired vehicle with its own fleet. This generated an annual gain of R $ 3.8 million, through the expressive gains in production and the reduction in the cost of hiring services, which have offset the increase in costs of having its own fleet. The computational model, with its many peculiarities, has been reproduced successfully, allowing for work solutions at low cost and without interference in the real system, distinguishing itself as a fundamental tool to solidify the company’s competitiveness.

  20. Simulation on Temperature and Ampacity of Mining Flame-proof High Voltage Cable Connector

    Directory of Open Access Journals (Sweden)

    Li Haiying

    2017-01-01

    Full Text Available To investigate the accident causes of mining flame-proof high voltage (F-HV cable connector, the temperature and ampacity of LBG1-200/6 high voltage cable connector are analyzed. At first, the material properties and structure of connector are introduced from the aspects of electrical, insulation and thermal. Then the electromagnetic field and thermal field coupling model of cable connector are established by the finite element method. Finally, in the numerical examples, temperature distribution and ampacity change caused by power harmonics, dielectric loss and slight structure change are quantitatively plotted and analyzed. The paper provides great insight into the security operation of F-HV cable connector.

  1. Detecting surface coal mining areas from remote sensing imagery: an approach based on object-oriented decision trees

    Science.gov (United States)

    Zeng, Xiaoji; Liu, Zhifeng; He, Chunyang; Ma, Qun; Wu, Jianguo

    2017-01-01

    Detecting surface coal mining areas (SCMAs) using remote sensing data in a timely and an accurate manner is necessary for coal industry management and environmental assessment. We developed an approach to effectively extract SCMAs from remote sensing imagery based on object-oriented decision trees (OODT). This OODT approach involves three main steps: object-oriented segmentation, calculation of spectral characteristics, and extraction of SCMAs. The advantage of this approach lies in its effective integration of the spectral and spatial characteristics of SCMAs so as to distinguish the mining areas (i.e., the extracting areas, stripped areas, and dumping areas) from other areas that exhibit similar spectral features (e.g., bare soils and built-up areas). We implemented this method to extract SCMAs in the eastern part of Ordos City in Inner Mongolia, China. Our results had an overall accuracy of 97.07% and a kappa coefficient of 0.80. As compared with three other spectral information-based methods, our OODT approach is more accurate in quantifying the amount and spatial pattern of SCMAs in dryland regions.

  2. Establishing Pine Monocultures and Mixed Pine-Hardwood Stands on Reclaimed Surface Mined Land in Eastern Kentucky: Implications for Forest Resilience in a Changing Climate

    Directory of Open Access Journals (Sweden)

    Geoffrey Bell

    2017-10-01

    Full Text Available Surface mining and mine reclamation practices have caused significant forest loss and forest fragmentation in Appalachia. Shortleaf pine (Pinus echinata is threatened by a variety of stresses, including diseases, pests, poor management, altered fire regimes, and climate change, and the species is the subject of a widescale restoration effort. Surface mines may present opportunity for shortleaf pine restoration; however, the survival and growth of shortleaf pine on these harsh sites has not been critically evaluated. This paper presents first-year survival and growth of native shortleaf pine planted on a reclaimed surface mine, compared to non-native loblolly pine (Pinus taeda, which has been highly successful in previous mined land reclamation plantings. Pine monoculture plots are also compared to pine-hardwood polyculture plots to evaluate effects of planting mix on tree growth and survival, as well as soil health. Initial survival of shortleaf pine is low (42%, but height growth is similar to that of loblolly pine. No differences in survival or growth were observed between monoculture and polyculture treatments. Additional surveys in coming years will address longer-term growth and survival patterns of these species, as well as changes to relevant soil health endpoints, such as soil carbon.

  3. Potential effects of surface coal mining on the hydrology of the Corral Creek area, Hanging Woman Creek coal field, southeastern Montana

    Science.gov (United States)

    McClymonds, N.E.

    1984-01-01

    The Corral Creek area of the Hanging Woman Creek coal field, 9 miles east of the Decker coal mines near the Tongue River, contains large reserves of Federal coal that have been identified for potential lease sale. A hydrologic study was conducted in the area to describe existing hydrologic systems and to study assess potential impacts of surface coal mining on local water resources. Hydrogeologic data collected indicate that aquifers are coal and sandstone beds within the Tongue River Member of the Fort Union Formation (Paleocene age) and sand and gravel in valley alluvium (Pleistocene and Holocene age). Surface-water resources are limited to a few spring-fed stock ponds in the higher parts of the area and the intermittent flow of Corral Creek near the mouth. Most of the stock ponds in the area become dry by midsummer. Mining of the Anderson coal bed would remove three stock wells and would lower the potentiometric surface within the coal and sandstone aquifers. The alluvial aquifer beneath Corral Creek and South Fork would be removed. Although mining would alter the existing hydrologic systems and remove several shallow wells, alternative ground-water supplies are available that could be developed to replace those lost by mining. (USGS)

  4. Mine drainage treatment

    OpenAIRE

    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...

  5. Failure of man-made cavities in salt and surface subsidence due to sulfur mining

    Energy Technology Data Exchange (ETDEWEB)

    Coates, G.K.; Lee, C.A.; McClain, W.C.; Senseny, P.E.

    1981-01-01

    An engineering data base relevant to subsidence due to sulfur mining and to structural failure of cavities in salt is established, evaluated and documented. Nineteen failure events are discussed. Based on these documented failure events, capabilities of and inputs to a mathematical model of cavity failure are determined. Two failure events are adequately documented for use in model verification studies. A conclusion of this study that is pertinent to the Strategic Petroleum Reserve is that cavity failures in dome salt are fairly rare, but that as the number of large cavities (especially those having large roof spans) increases, failures will probably be more common unless stability and failure mechanisms of cavities are better understood.

  6. Numerical Simulation of Floating Bodies in Extreme Free Surface Waves

    Science.gov (United States)

    Hu, Zheng Zheng; Causon, Derek; Mingham, Clive; Qiang, Ling

    2010-05-01

    and efficient. Firstly, extreme design wave conditions are generated in an empty NWT and compared with physical experiments as a precursor to calculations to investigate the survivability of the Bobber device operating in a challenging wave climate. Secondly, we consider a bench-mark test case involving in a first order regular wave maker acting on a fixed cylinder and Pelamis. Finally, a floating Bobber has been simulated under extreme wave conditions. These results will be reported at the meeting. Causon D.M., Ingram D.M., Mingham C.G., Yang G. Pearson R.V. (2000). Calculation of shallow water flows using a Cartesian cut cell approach. Advances in Water resources, 23: 545-562. Causon D.M., Ingram D.M., Mingham C.G. (2000). A Cartesian cut cell method for shallow water flows with moving boundaries. Advances in Water resources, 24: 899-911. Dalzell J.F. 1999 A note on finite depth second-order wave-wave interactions. Appl. Ocean Res. 21, 105-111. Ning D.Z., Zang J., Liu S.X. Eatock Taylor R. Teng B. & Taylor P.H. 2009 Free surface and wave kinematics for nonlinear focused wave groups. J. Ocean Engineering. Accepted. Hu Z.Z., Causon D.M., Mingham C.M. and Qian L.(2009). Numerical wave tank study of a wave energy converter in heave. Proceedlings 19th ISOPE conference, Osaka, Japan Qian L., Causon D.M. & Mingham C.G., Ingram D.M. 2006 A free-surface capturing method for two fluid flows with moving bodies. Proc. Roy. Soc. London, Vol. A 462 21-42.

  7. Implementation of paste backfill mining technology in Chinese coal mines.

    Science.gov (United States)

    Chang, Qingliang; Chen, Jianhang; 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.

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

    Directory of Open Access Journals (Sweden)

    Qingliang Chang

    2014-01-01

    Full Text Available 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.

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

    Science.gov (United States)

    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

  10. The political economy of regulation: Investigation of the relationship between design and performance standards in surface coal mining

    International Nuclear Information System (INIS)

    Walker, K.R.

    1991-01-01

    Research concerning political and economic regulatory policy was conducted on 15 randomly selected surface coal mines in Tennessee. Data on violations were collected over a 6-year period from 1979 through 1984. The primary purpose of this study was to investigate the approaches of the Carter and Reagan administrations concerning the implementation of design and performance regulations of Public Law 95-87. The study concluded that: (1) A change in political administration affects regulatory policy concerning enforcement practices. (2) Regulatory policy is altered in the direction of economic activity believed by an administration to be desirable to society and its constituents. (3) Elaborate rule making activity constrains market activity. (4) The coupling of design and performance standards should be retained. No difference was found in the number of violations for design and associated performance standards. Findings support the theory that it is the administration that affects change in regulatory policy, and not the regulatory construct for compliance with a mandate

  11. Human attitudes in environmental management: Fuzzy Cognitive Maps and policy option simulations analysis for a coal-mine ecosystem in China.

    Science.gov (United States)

    Zhang, Hong; Song, Jie; Su, Chao; He, Mengying

    2013-01-30

    Ecosystem management is a complex process, and every stakeholder's cognition plays a crucial role in it. In order to manage the ecosystem better, it is significant for the coal-mining environmental managers to choose appropriate measures, in accord with the stakeholders' interests. Hence, the purpose of this study is to assess knowledge of and attitudes towards coal-mine ecosystems among stakeholders and then simulate policy options in a typical coal-mine region in China. The Fuzzy Cognitive Mapping (FCM) method was used to develop a participatory ecosystem management model in research area. Combining the initial state of variables and the adjacency matrix getting from FCM, Artificial Neural Network (ANN) was used to conduct simulations. The results found that among stakeholder groups' FCM model, 'air pollution' and 'water pollution' are the most frequently mentioned variables, while 'health effects' and 'expansion of related industries' are the core variables. However, different stakeholders expressed diverse perceptions on coal-mine ecosystem management. Mine workers paid more attention to occupational safety and their health impacts inducted by air and water pollution during coal-mine process. Local residents were concerned with local economic development and welfare facilities improvement; they also concerned their health impacts raised by coal-mine related problems such as air and water pollution, traffic and noises. Managers emphasized economic interests and environmental projects with immediate environmental effects other than long-term ecosystem improvement. Engineers mentioned more variables than other groups; they believed that air pollution, water pollution, soil erosion and biodiversity loss were important. Scenario analysis for policy simulation based on ANN suggested that the local governments and enterprises should place an emphasis on protecting farmland, increasing vegetation coverage, reducing solid contamination and improving energy efficiency to

  12. Assessment of Radioactive Materials and Heavy Metals in the Surface Soil around the Bayanwula Prospective Uranium Mining Area in China

    Directory of Open Access Journals (Sweden)

    Haribala Bai

    2017-03-01

    Full Text Available The present work is the first systematic and large scale study on radioactive materials and heavy metals in surface soil around the Bayanwula prospective uranium mining area in China. In this work, both natural and anthropogenic radionuclides and heavy metals in 48 surface soil samples were analyzed using High Purity Germanium (HPGe γ spectrometry and inductively coupled plasma-mass spectrometry (ICP-MS. The obtained mean activity concentrations of 238U, 226Ra, 232Th, 40K, and 137Cs were 25.81 ± 9.58, 24.85 ± 2.77, 29.40 ± 3.14, 923.0 ± 47.2, and 5.64 ± 4.56 Bq/kg, respectively. The estimated average absorbed dose rate and annual effective dose rate were 76.7 ± 3.1 nGy/h and 83.1 ± 3.8 μSv, respectively. The radium equivalent activity, external hazard index, and internal hazard index were also calculated, and their mean values were within the acceptable limits. The estimated lifetime cancer risk was 3.2 × 10−4/Sv. The heavy metal contents of Cr, Ni, Cu, Zn, As, Cd, and Pb from the surface soil samples were measured and their health risks were then assessed. The concentrations of all heavy metals were much lower than the average backgrounds in China except for lead which was about three times higher than that of China’s mean. The non-cancer and cancer risks from the heavy metals were estimated, which are all within the acceptable ranges. In addition, the correlations between the radionuclides and the heavy metals in surface soil samples were determined by the Pearson linear coefficient. Strong positive correlations between radionuclides and the heavy metals at the 0.01 significance level were found. In conclusion, the contents of radionuclides and heavy metals in surface soil around the Bayanwula prospective uranium mining area are at a normal level.

  13. A multi-surface plasticity model for ductile fracture simulations

    Science.gov (United States)

    Keralavarma, Shyam M.

    2017-06-01

    The growth and coalescence of micro-voids in a material undergoing ductile fracture depends strongly on the loading path. Void growth occurs by diffuse plasticity in the material and is sensitive to the hydrostatic stress, while void coalescence occurs by the localization of plastic deformation in the inter-void ligaments under a combination of normal and shear stresses on the localization plane. In this paper, a micromechanics-based plasticity model is developed for an isotropic porous material, accounting for both diffuse and localized modes of plasticity at the micro-scale. A multi-surface approach is adopted, and two existing plasticity models that separately account for the two modes of yielding, above, are synthesized to propose an effective isotropic yield criterion and associated state evolution equations. The yield criterion is validated by comparison with quasi-exact numerical yield loci computed using a finite elements based limit analysis procedure. It is shown that the new criterion is in better agreement with the numerical loci than the Gurson model, particularly for large values of the porosity for which the loading path dependence of the yield stress is well predicted by the new model. Even at small porosities, it is shown that the new model predicts marginally lower yield stresses under low triaxiality shear dominated loadings compared to the Gurson model, in agreement with the numerical limit analysis data. Predictions for the strains to the onset of coalescence under proportional loading, obtained by numerically integrating the model, indicate that void coalescence tends to occur at relatively small plastic strain and porosity levels under shear dominated loadings. Implications on the prediction of ductility using the new model in fracture simulations are discussed.

  14. A plot tree structure to represent surface flow connectivity in rural catchments: definition and application for mining critical source areas and temporal conditions

    Science.gov (United States)

    Gascuel-Odoux, Chantal; Cordier, Marie-Odile; Grimaldi, Catherine; Salmon-Monviola, Jordy; Masson, Veronique; Squividant, Herve; Trepos, Ronan

    2013-04-01

    ., Tortrat F., Cordier M.O., 2009. A plot drainage network as a conceptual tool for the spatial representation of surface flow pathways in agricultural catchments. Computer and Geosciences, 35, 276-288. Gascuel-Odoux C., Aurousseau P., Cordier M.O., Durand P., Garcia F., Masson, V., Salmon-Monviola J., Tortrat F., Trepos, R. 2009. A decision-oriented model to evaluate the effect of land use and management on herbicide contamination in stream water. Environmental modelling and software, 24, 1433-1446. Gascuel-Odoux C., Aurousseau, P., Doray, T., Squividant, H., Macary, F., Uny, D., Grimaldi, C., 2011. Incorporating landscape features in a plot tree structure to represent surface flow connectivity in rural catchments. Hydrological Processes, 25, 3625-3636. Salmon-Monviola J., Gascuel-Odoux C., Garcia F., Tortrat F., Cordier M.O., Masson V., Trepos R., 2011. Simulating the effect of technical and environmental constraints on the spatio-temporal distribution of herbicide applications and stream losses. Agriculture, Environment and Ecosystems, 140, 382-394. Trepos, R., Masson V., Cordier, M.O., Gascuel-Odoux, C., Salmon-Monviola J., 2012. Mining simulation data by rule induction to determine critical source areas of stream water pollution by herbicides. Computers and Electronics in Agriculture 86: 75-88.

  15. Simulation of surface dynamics during dissolution as a function of the surface orientation: Implications for non-constant dissolution rates

    Science.gov (United States)

    Godinho, J. R. A.; Piazolo, S.; Evans, L.

    2014-12-01

    An important problem in geochemistry is the understanding of how changes occurring on a surface during dissolution affect the variability of measured dissolution rates. In this study a new approach to study the effect of surface dynamics on dissolution rates is tested by coupling experimental data with a numerical model that simulates the retreat of surface profiles during dissolution. We present specific results from the simulation of dissolution of fluorite surfaces. The equations that determine the retreat of a surface are based on experimentally obtained equations that relate the retreat rate of a surface to a single variable, the crystallographic orientation of the surface. Our results show that depending on the starting orientation, different types of topography are developed, similar to those observed experimentally. During the initial dissolution phase, changes of topography are rapid and associated with fast dissolution rates. The progressively slower dissolution rates are coupled with the development of surface segments with orientations that dissolve at a slower rate. Consequently, the overall retreat rate of a profile decreases during the simulation, and tends to a near-constant value. The results show a close relationship between dissolution rates, surface orientation and surface dynamics, which suggests that the dissolution rate of a specific mineral phase is not constant but varies with dissolution time and surface structure. This variability needs to be considered in the evaluation of experimentally derived dissolution rates, future dissolution experiments, and predictive kinetic models of dissolution.

  16. Nuclear waste repository simulation experiments (brine migration), Asse Mine of the Federal Republic of Germany: Quarterly brine migration data report, October--December 1985

    International Nuclear Information System (INIS)

    Eckert, J.L.; Kalia, H.N.; Coyle, A.J.

    1988-03-01

    The tenth brine migration data report describes experiments simulating a nuclear waste repository at the 800-m (2624-ft) level of the Asse Salt Mine in the Federal Republic of Germany from May 1983 through December 1985. This report describes the test equipment, the Asse Salt Mine, and the pretest properties of the salt in the test gallery. This report includes test data for 31 months of operations on brine migration rates, borehole pressure, salt temperatures and thermomechanical behavior of the salt. 3 refs., 118 figs., 93 tabs

  17. Quarterly brine migration data report, May-September 1983: Nuclear Waste Repository simulation experiments (brine migration), Asse Mine of the Federal Republic of Germany

    International Nuclear Information System (INIS)

    Coyle, A.J.; Kalia, H.N.; Eckert, J.L.

    1987-04-01

    The first quarterly brine migration data report describes experiments simulating a nuclear waste repository at the 800-m (2624-ft) level of the Asse Salt Mine in the Federal Republic of Germany from May 1983 through September 1983. This report describes the test equipment, the Asse Salt Mine, and the pretest properties of the salt in the test gallery. This report also includes test data for the first 4 months of operations on brine migration rates, borehole pressure, salt temperatures, and thermomechanical behavior of the salt. The duration of the experiments will be approximately 2 years, ending in December 1985. 83 figs., 55 tabs

  18. Mining for osteogenic surface topographies: In silico design to in vivo osseo-integration.

    Science.gov (United States)

    Hulshof, Frits F B; Papenburg, Bernke; Vasilevich, Aliaksei; Hulsman, Marc; Zhao, Yiping; Levers, Marloes; Fekete, Natalie; de Boer, Meint; Yuan, Huipin; Singh, Shantanu; Beijer, Nick; Bray, Mark-Anthony; Logan, David J; Reinders, Marcel; Carpenter, Anne E; van Blitterswijk, Clemens; Stamatialis, Dimitrios; de Boer, Jan

    2017-08-01

    Stem cells respond to the physicochemical parameters of the substrate on which they grow. Quantitative material activity relationships - the relationships between substrate parameters and the phenotypes they induce - have so far poorly predicted the success of bioactive implant surfaces. In this report, we screened a library of randomly selected designed surface topographies for those inducing osteogenic differentiation of bone marrow-derived mesenchymal stem cells. Cell shape features, surface design parameters, and osteogenic marker expression were strongly correlated in vitro. Furthermore, the surfaces with the highest osteogenic potential in vitro also demonstrated their osteogenic effect in vivo: these indeed strongly enhanced bone bonding in a rabbit femur model. Our work shows that by giving stem cells specific physicochemical parameters through designed surface topographies, differentiation of these cells can be dictated. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Doomed reservoirs in Kansas, USA? Climate change and groundwater mining on the Great Plains lead to unsustainable surface water storage

    Science.gov (United States)

    Brikowski, T. H.

    2008-06-01

    SummaryStreamflow declines on the Great Plains of the US are causing many Federal reservoirs to become profoundly inefficient, and will eventually drive them into unsustainability as negative annual reservoir water budgets become more common. The streamflow declines are historically related to groundwater mining, but since the mid-1980s correlate increasingly with climate. This study highlights that progression toward unsustainability, and shows that future climate change will continue streamflow declines at historical rates, with severe consequences for surface water supply. An object lesson is Optima Lake in the Oklahoma Panhandle, where streamflows have declined 99% since the 1960s and the reservoir has never been more than 5% full. Water balances for the four westernmost Federal reservoirs in Kansas (Cedar Bluff, Keith Sebelius, Webster and Kirwin) show similar tendencies. For these four, reservoir inflow has declined by 92%, 73%, 81% and 64% respectively since the 1950s. Since 1990 total evaporated volumes relative to total inflows amounted to 68%, 83%, 24% and 44% respectively. Predictions of streamflow and reservoir performance based on climate change models indicate 70% chance of steady decline after 2007, with a ˜50% chance of failure (releases by gravity flow impossible) of Cedar Bluff Reservoir between 2007 and 2050. Paradoxically, a 30% chance of storage increase prior 2020 is indicated, followed by steady declines through 2100. Within 95% confidence the models predict >50% decline in surface water resources between 2007 and 2050. Ultimately, surface storage of water resources may prove unsustainable in this region, forcing conversion to subsurface storage.

  20. Knowledge Mining Based on Environmental Simulation Applied to Wind Farm Power Forecasting

    Directory of Open Access Journals (Sweden)

    Dongxiao Niu

    2013-01-01

    Full Text Available Considering the inherent variability and uncertainty of wind power generation, in this study, a self-organizing map (SOM combined with rough set theory clustering technique (RST is proposed to extract the relative knowledge and to choose the most similar history situation and efficient data for wind power forecasting with numerical weather prediction (NWP. Through integrating the SOM and RST methods to cluster the historical data into several classes, the approach could find the similar days and excavate the hidden rules. According to the data reprocessing, the selected samples will improve the forecast accuracy echo state network (ESN trained by the class of the forecasting day that is adopted to forecast the wind power output accordingly. The developed methods are applied to a case of power forecasting in a wind farm located in northwest of China with wind power data from April 1, 2008, to May 6, 2009. In order to verify its effectiveness, the performance of the proposed method is compared with the traditional backpropagation neural network (BP. The results demonstrated that knowledge mining led to a promising improvement in the performance for wind farm power forecasting.

  1. Simulation of a Lunar Surface Base Power Distribution Network for the Constellation Lunar Surface Systems

    Science.gov (United States)

    Mintz, Toby; Maslowski, Edward A.; Colozza, Anthony; McFarland, Willard; Prokopius, Kevin P.; George, Patrick J.; Hussey, Sam W.

    2010-01-01

    The Lunar Surface Power Distribution Network Study team worked to define, breadboard, build and test an electrical power distribution system consistent with NASA's goal of providing electrical power to sustain life and power equipment used to explore the lunar surface. A testbed was set up to simulate the connection of different power sources and loads together to form a mini-grid and gain an understanding of how the power systems would interact. Within the power distribution scheme, each power source contributes to the grid in an independent manner without communication among the power sources and without a master-slave scenario. The grid consisted of four separate power sources and the accompanying power conditioning equipment. Overall system design and testing was performed. The tests were performed to observe the output and interaction of the different power sources as some sources are added and others are removed from the grid connection. The loads on the system were also varied from no load to maximum load to observe the power source interactions.

  2. Effects of mine strata thermal behavior and mine initial temperatures on mobile refuge alternative temperature.

    Science.gov (United States)

    Yantek, D S; Yan, L; Bissert, P T; Klein, M D

    2017-04-01

    Federal regulations require the installation of refuge alternatives (RAs) in underground coal mines. Mobile RAs have a limited ability to dissipate heat, and heat buildup can lead to a life-threatening condition as the RA internal air temperature and relative humidity increase. The U.S. National Institute for Occupational Safety and Health (NIOSH) performed heat testing on a 10-person tent-type training RA and contracted ThermoAnalytics Inc. to develop a validated thermal simulation model of the tested RA. The model was used to examine the effects of the constant mine strata temperature assumption, initial mine air temperature, initial mine strata surface temperature (MSST), initial mine strata temperature at depth (MSTD) and mine strata thermal behavior on RA internal air temperature using 117 W (400 Btu/h) of sensible heat input per simulated miner. For the studied RA, when the mine strata temperature was treated as a constant, the final predicted RA internal air temperature was 7.1°C (12.8°F) lower than it was when the mine strata thermal behavior was included in the model. A 5.6°C (10.0°F) increase in the initial MSST resulted in a 3.9°C (7.1°F) increase in the final RA internal air temperature, whereas a 5.6°C (10°F) increase in the initial MSTD yielded a 1.4°C (2.5°F) increase in the final RA internal air temperature. The results indicate that mine strata temperature increases and mine strata initial temperatures must be accounted for in the physical testing or thermal simulations of RAs.

  3. Wintertime land surface characteristics in climatic simulations over ...

    Indian Academy of Sciences (India)

    eastward moving low-pressure synoptic weather systems, called Western Disturbances (WDs). (Pisharoty and Desai .... Land surface processes are controlled by surface roughness and albedo. Different land surfaces will have different roughness length and albedo. Table 1 illustrates vegetation types and their correspond-.

  4. The use of landscape fabric and supplemental irrigation to enhance survival and growth of woody perennials planted on reclaimed surface mine lands

    Science.gov (United States)

    R .C. Musselman; F. W. Smith; W. D. Shepperd; L. A. Asherin; B. W. Gee

    2009-01-01

    A study was initiated to determine the effectiveness of landscape fabric and supplemental irrigation in survival and growth of woody perennials planted on reclaimed surface coal mine lands. The study compared growth and survival of nursery grown potted aspen and serviceberry planted with or without landscape fabric, and with or without biweekly supplemental irrigation...

  5. One-year response of American sycamore (Platanus occidentalis L.) and black locust (Robinia pseudoacacia L.) to granular fertilizer applications on a reclaimed surface mine in eastern Kentucky

    Science.gov (United States)

    Josh Brinks; John Lhotka; Chris. Barton

    2011-01-01

    The establishment of intensively managed woody energy crops on reclaimed surface mine lands provides an opportunity to diversify domestic biomass sources, while increasing the productivity and economic value of underutilized land. Our objective is to test the effect of fertilization on the growth and biomass accumulation of American sycamore (Platanus...

  6. Evaluation of water quality in surface water and shallow groundwater: a case study of a rare earth mining area in southern Jiangxi Province, China.

    Science.gov (United States)

    Hao, Xiuzhen; Wang, Dengjun; Wang, Peiran; Wang, Yuxia; Zhou, Dongmei

    2016-01-01

    This study was conducted to evaluate the quality of surface water and shallow groundwater near a rare earth mining area in southern Jiangxi Province, China. Water samples from paddy fields, ponds, streams, wells, and springs were collected and analyzed. The results showed that water bodies were characterized by low pH and high concentrations of total nitrogen (total N), ammonium nitrogen (NH4 (+)-N), manganese (Mn), and rare earth elements (REEs), which was likely due to residual chemicals in the soil after mining activity. A comparison with the surface water standard (State Environmental Protection Administration & General Administration of Quality Supervision, Inspection and Quarantine of China GB3838, 2002) and drinking water sanitary standard (Ministry of Health & National Standardization Management Committee of China GB5749, 2006) of China revealed that 88 % of pond and stream water samples investigated were unsuitable for agricultural use and aquaculture water supply, and 50 % of well and spring water samples were unsuitable for drinking water. Moreover, significant cerium (Ce) negative and heavy REEs enrichment was observed after the data were normalized to the Post-Archean Australian Shales (PAAS). Principal component analysis indicated that the mining activity had a more significant impact on local water quality than terrace field farming and poultry breeding activities. Moreover, greater risk of water pollution and adverse effects on local residents' health was observed with closer proximity to mining sites. Overall, these findings indicate that effective measures to prevent contamination of surrounding water bodies from the effects of mining activity are needed.

  7. Effect of Simulant Type on the Absorptance and Emittance of Dusted Thermal Control Surfaces in a Simulated Lunar Environment

    Science.gov (United States)

    Gaier, James R.

    2010-01-01

    During the Apollo program the effects of lunar dust on thermal control surfaces was found to be more significant than anticipated, with several systems overheating due to deposition of dust on them. In an effort to reduce risk to future missions, a series of tests has been initiated to characterize the effects of dust on these surfaces, and then to develop technologies to mitigate that risk. Given the variations in albedo across the lunar surface, one variable that may be important is the darkness of the lunar dust, and this study was undertaken to address that concern. Three thermal control surfaces, AZ-93 white paint and AgFEP and AlFEP second surface mirrors were dusted with three different lunar dust simulants in a simulated lunar environment, and their integrated solar absorptance ( ) and thermal emittance ( ) values determined experimentally. The three simulants included JSC-1AF, a darker mare simulant, NU-LHT-1D, a light highlands simulant, and 1:1 mixture of the two. The response of AZ-93 was found to be slightly more pronounced than that of AgFEP. The increased with fractional dust coverage in both types of samples by a factor of 1.7 to 3.3, depending on the type of thermal control surface and the type of dust. The of the AZ-93 decreased by about 10 percent when fully covered by dust, while that of AgFEP increased by about 10 percent. It was found that / varied by more than a factor of two depending on the thermal control surface and the darkness of the dust. Given that the darkest simulant used in this study may be lighter than the darkest dust that could be encountered on the lunar surface, it becomes apparent that the performance degradation of thermal control surfaces due to dust on the Moon will be strongly dependent on the and of the dust in the specific locality

  8. Optimisation of reclamation approaches to land affected by surface coal mining

    Energy Technology Data Exchange (ETDEWEB)

    Kabrna, M.; Hendrychova, M. [Vyzkumny ustav pro hnede uhli a.s. (Czech Republic); Czech Univ. of Life Sciences, Prague (Czech Republic). Faculty of Environmental Science; Salek, M. [Czech Univ. of Life Sciences, Prague (Czech Republic). Faculty of Environmental Science; Rehor, M. [Vyzkumny ustav pro hnede uhli a.s. (Czech Republic)

    2009-07-01

    Since the 1950s, reclamation of land affected by brown coal mining in the Czech Republic has been conducted. Since this time, there has been significant improvement in quality development of reclamation measures. This paper discussed the results of different studies where technically reclaimed sites as well as naturally developed sites were investigated. The paper discussed the methodology of the study as well as results of succession versus reclamation and next preferences. One of the studies that was examined involved four groups of animals that have a close relation to soil and plant vegetation. These included ground beetles, bugs, molluscs, and birds. This study found that the spontaneously developed sites could be characterized by the same or a higher biodiversity than those technically reclaimed. The second study examined bird nest preferences either to domestic or to exotic trees. The results showed that although exotic trees dominate on reclaimed sites, the birds preferred the domestic trees for nesting. It was concluded that the natural succession could play a significant role within reclamation practices, particularly on those sites where higher species diversity is desirable. 10 refs., 2 figs.

  9. 30 CFR 77.1712 - Reopening mines; notification; inspection prior to mining.

    Science.gov (United States)

    2010-07-01

    ... to mining. 77.1712 Section 77.1712 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... prior to mining. Prior to reopening any surface coal mine after it has been abandoned or declared... an authorized representative of the Secretary before any mining operations in such mine are...

  10. 30 CFR 819.21 - Auger mining: Protection of underground mining.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Auger mining: Protection of underground mining. 819.21 Section 819.21 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT... STANDARDS-AUGER MINING § 819.21 Auger mining: Protection of underground mining. Auger holes shall not extend...

  11. Simulation model of pollution spreading in the water bodies affected by mining mill

    OpenAIRE

    Kalinkina Natalia Mikhailovna; Korosov Andrey Viktorovich

    2015-01-01

    Water bodies of the northern Karelia are polluted by liquid wastes of Kostomukshsky iron ore-dressing mill. The main components of these wastes are potassium ions. The processes of the potassium spreading in lake-river system of the River Kenty were studied using simulation modeling. For water bodies, where chemical observations were not carried out, the reconstruction of data was realized. The parameters of the model (constants of potassium transfer for seven lakes) were calculated. These co...

  12. PedMine – A simulated annealing algorithm to identify maximally unrelated individuals in population isolates

    OpenAIRE

    Douglas, Julie A.; Sandefur, Conner I.

    2008-01-01

    In family-based genetic studies, it is often useful to identify a subset of unrelated individuals. When such studies are conducted in population isolates, however, most if not all individuals are often detectably related to each other. To identify a set of maximally unrelated (or equivalently, minimally related) individuals, we have implemented simulated annealing, a general-purpose algorithm for solving difficult combinatorial optimization problems. We illustrate our method on data from a ge...

  13. Mined-out land

    International Nuclear Information System (INIS)

    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

  14. Identification of linkages between potential Environmental and Social Impacts of Surface Mining and Ecosystem Services in Thar Coal field, Pakistan

    Science.gov (United States)

    Hina, A.

    2017-12-01

    Although Thar coal is recognized to be one of the most abundant fossil fuel that could meet the need to combat energy crisis of Pakistan, but there still remains a challenge to tackle the associated environmental and socio-ecological changes and its linkage to the provision of ecosystem services of the region. The study highlights the importance of considering Ecosystem service assessment to be undertaken in all strategic Environmental and Social Assessments of Thar coal field projects. The three-step approach has been formulated to link the project impacts to the provision of important ecosystem services; 1) Identification of impact indicators and parameters by analyzing the environmental and social impacts of surface mining in Thar Coal field through field investigation, literature review and stakeholder consultations; 2) Ranking of parameters and criteria alternatives using Multi-criteria Decision Analysis(MCDA) tool: (AHP method); 3) Using ranked parameters as a proxy to prioritize important ecosystem services of the region; The ecosystem services that were prioritized because of both high significance of project impact and high project dependence are highlighted as: Water is a key ecosystem service to be addressed and valued due to its high dependency in the area for livestock, human wellbeing, agriculture and other purposes. Crop production related to agricultural services, in association with supply services such as soil quality, fertility, and nutrient recycling and water retention need to be valued. Cultural services affected in terms of land use change and resettlement and rehabilitation factors are recommended to be addressed. The results of the analysis outline a framework of identifying these linkages as key constraints to foster the emergence of green growth and development in Pakistan. The practicality of implementing these assessments requires policy instruments and strategies to support human well-being and social inclusion while minimizing

  15. Virtual simulation of maneuvering captive tests for a surface vessel

    Directory of Open Access Journals (Sweden)

    Ahmad Hajivand

    2015-09-01

    Full Text Available Hydrodynamic derivatives or coefficients are required to predict the maneuvering characteristics of a marine vehicle. These derivatives are obtained numerically for a DTMB 5512 model ship by virtual simulating of captive model tests in a CFD environment. The computed coefficients are applied to predict the turning circle and zigzag maneuvers of the model ship. The comparison of the simulated results with the available experimental data shows a very good agreement among them. The simulations show that the CFD is precise and affordable tool at the preliminary design stage to obtain maneuverability performance of a marine vehicles.

  16. Protection and restoration of soil in mining operations which disrupt the surface of the earth, with the open pit method of working minerals (problems, obtained data and recommendations)

    Energy Technology Data Exchange (ETDEWEB)

    Debelak, M.

    1981-01-01

    A critical analysis is made of the current state and the ways to solve the problem of protection and restoration of the sections of the earth's surface and sources of drinking water which can be disrupted with the open pit method of working minerals. The need is advanced for creating a system of coordination and planning of the activity of all the organizations associated with working minerals, restoration operations and inspection of them. The order of preparation for recultivation during mining operations (in particular, storage of the fertile ground) and conducting them after the end of mining are described.

  17. Polar Organic Compounds in Surface Waters Collected Near Lead-Zinc Mine and Milling Operations in Missouri

    Science.gov (United States)

    Rostad, C. E.; Schmitt, C. J.; Schumacher, J. G.; Leiker, T. J.

    2007-12-01

    Surface-water samples were collected near a lead mine and mill tailings about 70 miles southwest of St. Louis, Missouri, during the summer of 2006. The purpose of this sampling was to determine if polar organic compounds were present that could be a cause of documented negative impacts to biota downstream. Water samples contained relatively high concentrations of dissolved organic carbon for surface waters (greater than 20 mg/L), but were colorless, which precluded naturally occurring aquatic humic or fulvic acids. Previous analysis indicated that samples were devoid of pesticides and acid/base/neutral extractable semi-volatile organic compounds, such as polycyclic aromatic hydrocarbons. After isolation by three different types of solid phase extraction, samples were analyzed by electrospray ionization/mass spectrometry. Polar organic compounds commonly used in the milling process, such as alkyl xanthates, were not found; however, xanthate degradation products were detected. Most of the polar organic compounds identified contained sulfonate groups, which are characteristic of some of the reagents used in the milling process. Sulfonate compounds may have low sorption onto soil or sediments and be mobile in the aqueous environment.

  18. Simulation techniques of medium or small sized coal mining; Sistema de simulacion de labores de minas subterraneas de carbon de tamano mediano o pequeno

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-01

    Usually an underground mining company designs new production systems in order to reach higher productivity levels, but there is always some uncertainty about reaching the planned figures. This research project, so called Project SimCAR, applies to medium or small sized coal mining companies and tries to become a powerful tool in helping technical staff to answer questions about how future systems will behave. The project`s paradigm is to use computer simulation techniques in order to diminish the implicit uncertainty associated to coal mining activities. As a result, this implies to obtain the best possible scenarios for real economic investments in mine planning. The final programs we have built help technical staff to: 1. Study existing systems in depth. The precision of the resulting model exclusively depends on the correctness of input data and a perfect understanding of the system`s logic processes. 2. Perform several changes on the input system variables over the simulated models in order to allow the technical staff to know the system will react under several conditions. 3. Introduce new strategies on the model construction in order to get a complete optimization under productive and economic viewpoints. (Author)

  19. Mining Hidden Gems Beneath the Surface: A Look At the Invisible Web.

    Science.gov (United States)

    Carlson, Randal D.; Repman, Judi

    2002-01-01

    Describes resources for researchers called the Invisible Web that are hidden from the usual search engines and other tools and contrasts them with those resources available on the surface Web. Identifies specialized search tools, databases, and strategies that can be used to locate credible in-depth information. (Author/LRW)

  20. Reduction of surface subsidence risk by fly ash exploitation as filling material in deep mining areas

    Czech Academy of Sciences Publication Activity Database

    Trčková, Jiřina; Šperl, Jan

    2010-01-01

    Roč. 53, č. 2 (2010), s. 251-258 ISSN 0921-030X Institutional research plan: CEZ:AV0Z30460519 Keywords : undermining * subsidence of the surface * impact reduction Subject RIV: DO - Wilderness Conservation Impact factor: 1.398, year: 2010 www.springerlink.com/content/y8257893528lp56w/

  1. Experimental 3-D modelling of surface subsidence affected by underground mining activities

    Czech Academy of Sciences Publication Activity Database

    Trčková, Jiřina

    2009-01-01

    Roč. 109, č. 12 (2009), s. 739-744 ISSN 0038-223X R&D Projects: GA AV ČR IAA2119402 Institutional research plan: CEZ:AV0Z30460519 Keywords : undermining * subsidence of surface * 3-D experimental model Subject RIV: DO - Wilderness Conservation Impact factor: 0.216, year: 2009

  2. Integrated mined-area reclamation and land use planning. Volume 3F. A case study of surface mining and reclamation planning: Cannelton Mine No. 9-S, Cannelton, West Virginia

    Energy Technology Data Exchange (ETDEWEB)

    Bogner, J E; Perry, A O

    1977-02-01

    A mountain-top removal coal mining operation in south-central West Virginia is examined in this case study. A 2010 acre tract that is partly owned and partly leased by Cannelton Industries, Inc., has been about half stripped of the 5 Block and 6 Block Coals. The surrounding land area is characterized by steep-sided hills and generally lacks extensive tracts of level land suitable for agricultural or residential/commercial development. The Cannelton operation, which has already leveled several ridges, is creating areas which may be considered to have a higher land use potential than before mining. Although this site is generally isolated from urbanized areas and thus from structured regional planning efforts, it merits study as an excellent example of an innovating mining technique and integrated site-specific mining and reclamation planning.

  3. Generic framework for mining cellular automata models on protein-folding simulations.

    Science.gov (United States)

    Diaz, N; Tischer, I

    2016-05-13

    Cellular automata model identification is an important way of building simplified simulation models. In this study, we describe a generic architectural framework to ease the development process of new metaheuristic-based algorithms for cellular automata model identification in protein-folding trajectories. Our framework was developed by a methodology based on design patterns that allow an improved experience for new algorithms development. The usefulness of the proposed framework is demonstrated by the implementation of four algorithms, able to obtain extremely precise cellular automata models of the protein-folding process with a protein contact map representation. Dynamic rules obtained by the proposed approach are discussed, and future use for the new tool is outlined.

  4. Simulation model of pollution spreading in the water bodies affected by mining mill

    Directory of Open Access Journals (Sweden)

    Kalinkina Natalia Mikhailovna

    2015-09-01

    Full Text Available Water bodies of the northern Karelia are polluted by liquid wastes of Kostomukshsky iron ore-dressing mill. The main components of these wastes are potassium ions. The processes of the potassium spreading in lake-river system of the River Kenty were studied using simulation modeling. For water bodies, where chemical observations were not carried out, the reconstruction of data was realized. The parameters of the model (constants of potassium transfer for seven lakes were calculated. These constants reflect the hydrological regime of water bodies and characterize high-speed transfer of potassium in the upstream and downstream, and low transfer rate - in the middle stream. It is shown that the vast majority of potassium (70% is carried out of the system Kenty and enters the lake Srednee Kuito

  5. Surface coal mine land reclamation using a dry flue gas desulfurization product: Short-term and long-term water responses.

    Science.gov (United States)

    Chen, Liming; Stehouwer, Richard; Tong, Xiaogang; Kost, Dave; Bigham, Jerry M; Dick, Warren A

    2015-09-01

    Abandoned coal-mined lands are a worldwide concern due to their potential negative environmental impacts, including erosion and development of acid mine drainage. A field study investigated the use of a dry flue gas desulfurization product for reclamation of abandoned coal mined land in USA. Treatments included flue gas desulfurization product at a rate of 280 Mg ha(-1) (FGD), FGD at the same rate plus 112 Mg ha(-1) yard waste compost (FGD/C), and conventional reclamation that included 20 cm of re-soil material plus 157 Mg ha(-1) of agricultural limestone (SOIL). A grass-legume sward was planted after treatment applications. Chemical properties of surface runoff and tile water (collected from a depth of 1.2m below the ground surface) were measured over both short-term (1-4 yr) and long-term (14-20 yr) periods following reclamation. The pH of surface runoff water was increased from approximately 3, and then sustained at 7 or higher by all treatments for up to 20 yr, and the pH of tile flow water was also increased and sustained above 5 for 20 yr. Compared with SOIL, concentrations of Ca, S and B in surface runoff and tile flow water were generally increased by the treatments with FGD product in both short- and long-term measurements and concentrations of the trace elements were generally not statistically increased in surface runoff and tile flow water over the 20-yr period. However, concentrations of As, Ba, Cr and Hg were occasionally elevated. These results suggest the use of FGD product for remediating acidic surface coal mined sites can provide effective, long-term reclamation. Copyright © 2015. Published by Elsevier Ltd.

  6. Indian deep-sea environment experiment (INDEX): Monitoring the restoration of marine enviroment after artificial disturbance to simulate deep-sea mining in central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Sharma, R.

    Erratum Marine Georesources and Geotechnology vol. 23, no. 4 (September–December 2005) was a special issue, but this was not indicated. The correct special issue information is below. Indian Deep-Sea Environment Experiment (INDEX): Monitoring... the restoration of marine environment after artificial disturbance to simulate deep-sea mining in Central Indian Basin Guest Editor Rahul Sharma Note from guest editor A special issue on Indian Deep-sea Environment Experiment (INDEX) conducted by the scientists...

  7. Simulations for Surface Evolvement and Footing Effect in ICP DRIE Fabrications

    International Nuclear Information System (INIS)

    Zhang Jian; Huang Qingan; Li Weihua

    2006-01-01

    Simulations of surface evolvement are performed using an ICP DRIE model, in which a new method is adopted for the material identification. The simulation and experimental results are shown in this paper, which indicate that the veracity provided by this modified model is satisfied. The high-efficiency of this model over other former ones are due to the ability of identification of different material by uniform algorithm, and accordingly, it has much shorter executing time. Further more, an approximate model is presented to simulate the footing effect in DRIE fabrications, with the simulation results of the surface affected by footing effect in accordance to the experiments

  8. Wintertime land surface characteristics in climatic simulations over ...

    Indian Academy of Sciences (India)

    culture and tourism. To assess such interplay, we conducted and analyzed two sets of model runs: a control run (CONT), in which the fine scale BATS scheme is not used and therefore the land sur- face has the same resolution as the ..... Higher precipitation events are well simulated by both the experiments in two.

  9. Characterization of photosynthetic gas exchange in leaves under simulated adaxial and abaxial surfaces alternant irradiation.

    Science.gov (United States)

    Zhang, Zi-Shan; Li, Yu-Ting; Gao, Hui-Yuan; Yang, Cheng; Meng, Qing-Wei

    2016-07-05

    Previous investigations on photosynthesis have been performed on leaves irradiated from the adaxial surface. However, leaves usually sway because of wind. This action results in the alternating exposure of both the adaxial and abaxial surfaces to bright sunlight. To simulate adaxial and abaxial surfaces alternant irradiation (ad-ab-alt irradiation), the adaxial or abaxial surface of leaves were exposed to light regimes that fluctuated between 100 and 1,000 μmol m(-2) s(-1). Compared with constant adaxial irradiation, simulated ad-ab-alt irradiation suppressed net photosynthetic rate (Pn) and transpiration (E) but not water use efficiency. These suppressions were aggravated by an increase in alternant frequency of the light intensity. When leaves were transferred from constant light to simulated ad-ab-alt irradiation, the maximum Pn and E during the high light period decreased, but the rate of photosynthetic induction during this period remained constant. The sensitivity of photosynthetic gas exchange to simulated ad-ab-alt irradiation was lower on abaxial surface than adaxial surface. Under simulated ad-ab-alt irradiation, higher Pn and E were measured on abaxial surface compared with adaxial surface. Therefore, bifacial leaves can fix more carbon than leaves with two "sun-leaf-like" surfaces under ad-ab-alt irradiation. Photosynthetic research should be conducted under dynamic conditions that better mimic nature.

  10. Finite element simulation of shallow-buried and mining tunnelling in adjacent frame structures

    Directory of Open Access Journals (Sweden)

    Chun-lai Chen

    2014-05-01

    Full Text Available By using three dimensional software MIDAS/GTS, the interactions among structures-soil-tunnel system is considered in this paper, and the working condition of shallow-buried underground excavation is simulated in the foundation of frame structures with the short-pile. The loadings and deformations of structures are studied before and after the tunnelling, and the influences of the following factors, including the horizontal position of tunnel and building, the height of building and the soil property, are analyzed. It is indicated that when the horizontal distance L equals zero (the distance between building axis to the tunnel axis, the building settlement increases gradually and shows a normal distribution during and after the tunnelling. Due to the small stiffness of frame structures with short-pile foundations, the building has large nonuniform settlement. When the distance of excavation is no less than 1.8 times of the thickness of overburden soil, the building settlement becomes stable, and the first principal stress P1 and maximum deformation rate E1 generally show a trend of decrease. With the increasing L, P1 and E1 will decrease accordingly, and the buildings tend to be inclined toward the tunnel. For a relatively larger distance, the building is nearly not affected.

  11. Seasonal and spatial variations in microbial community structure and diversity in the acid stream draining across an ongoing surface mining site.

    Science.gov (United States)

    Tan, Gui-Liang; Shu, Wen-Sheng; Zhou, Wen-Hua; Li, Xiang-Li; Lan, Chong-Yu; Huang, Li-Nan

    2009-11-01

    This study examined the microbial community in an acidic stream draining across the Yun-Fu pyrite mine (Guangdong, China), where extremely acidic mine water is a persistent feature due to the intensive surface mining activities. Analysis of terminal restriction fragment length polymorphism (TRFLP) of 16S rRNA gene sequences showed that microbial populations varied spatially and seasonally and correlated with geochemical and physical conditions. After the stream moves from underground to the surface, the microbial community in the acidic water rapidly evolves into a distinct community close to that in the downstream storage pond. Comparisons of TRFLP peaks with sequenced clone libraries indicated that bacteria related to the recently isolated iron-oxidizer Ferrovum myxofaciens dominated the acidophilic community throughout the year except for the samples collected in spring from the storage pond, where Ferroplasma acidiphilum-like archaea represented the most abundant group. Acidithiobacillus ferrooxidans-affiliated organisms increased along the acid stream and remained common over the year, whereas Leptospirillum ferrooxidans-like bacteria were negligible or even not detected in the analyzed samples. The data indicate that changes in environmental conditions are accompanied by significant shifts in community structure of the prokaryotic assemblages at this opencast mining site.

  12. Environmental consequences of the Retsof Salt Mine roof collapse

    Science.gov (United States)

    Yager, Richard M.

    2013-01-01

    In 1994, the largest salt mine in North America, which had been in operation for more than 100 years, catastrophically flooded when the mine ceiling collapsed. In addition to causing the loss of the mine and the mineral resources it provided, this event formed sinkholes, caused widespread subsidence to land, caused structures to crack and subside, and changed stream flow and erosion patterns. Subsequent flooding of the mine drained overlying aquifers, changed the groundwater salinity distribution (rendering domestic wells unusable), and allowed locally present natural gas to enter dwellings through water wells. Investigations including exploratory drilling, hydrologic and water-quality monitoring, geologic and geophysical studies, and numerical simulation of groundwater flow, salinity, and subsidence have been effective tools in understanding the environmental consequences of the mine collapse and informing decisions about management of those consequences for the future. Salt mines are generally dry, but are susceptible to leaks and can become flooded if groundwater from overlying aquifers or surface water finds a way downward into the mined cavity through hundreds of feet of rock. With its potential to flood the entire mine cavity, groundwater is a constant source of concern for mine operators. The problem is compounded by the viscous nature of salt and the fact that salt mines commonly lie beneath water-bearing aquifers. Salt (for example halite or potash) deforms and “creeps” into the mined openings over time spans that range from years to centuries. This movement of salt can destabilize the overlying rock layers and lead to their eventual sagging and collapse, creating permeable pathways for leakage of water and depressions or openings at land surface, such as sinkholes. Salt is also highly soluble in water; therefore, whenever water begins to flow into a salt mine, the channels through which it flows increase in diameter as the surrounding salt dissolves

  13. Long-term Surface Temperature (LoST) Database as a Complement for GCM Preindustrial Simulations

    Science.gov (United States)

    Cuesta-Valero, F. J.; García-García, A.; Beltrami, H.; Zorita, E.

    2017-12-01

    Control climate simulations aim to provide a stationary state to General Circulation Models (GCMs) under constant preindustrial conditions (piControl simulations). This stationary state is then used as initial conditions in GCM simulations to provide a stable and realistic climatology, reducing the potential bias in such simulations. However, it is difficult to provide a reference to assess the climatology of piControl simulations due to the lack of long-term preindustrial observations. We explore the use of long-term ground surface temperature estimates from borehole temperature profiles as an additional reference that may be useful for the initialization procedure of GCM simulations. We compare five last millennium simulations and five preindustrial control simulations from the third phase of the Palaeoclimate Modelling Intercomparison Project (PMIP3) and the fifth phase of the Coupled Model Intercomparison Project (CMIP5) archives against estimates of long-term preindustrial ground surface temperatures from 514 borehole temperature profiles over North America. These long-term surface temperatures are retrieved from the quasi-equilibrium state of the subsurface thermal regime in each temperature profile, which is estimated from the deepest section of the profile. That is, the equilibrium state is recovered from the least affected part of the temperature profile by the recent changes in the surface energy balance. The subsurface temperatures at the bottom part of each profile depend linearly on depth, and the extrapolation of this linear behavior to the surface is interpreted as the long-term surface temperature (T0 temperature) at each borehole site. Our results suggest that the ground surface temperature estimates from borehole data could be employed as a reference within piControl simulations to enhance the quality of the initial conditions in GCM climate simulations.

  14. High intensity surface plasma waves, theory and PIC simulations

    Science.gov (United States)

    Raynaud, M.; Héron, A.; Adam, J.-C.

    2018-01-01

    With the development of intense (>1019 W cm‑2) short pulses (≤25 fs) laser with very high contrast, surface plasma wave (SPW) can be explored in the relativistic regime. As the SPW propagates with a phase velocity close to the speed of light it may results in a strong acceleration of electron bunches along the surface permitting them to reach relativistic energies. This may be important e.g. for applications in the field of plasma-based accelerators. We investigate in this work the excitation of SPWs on grating preformed over-dense plasmas for laser intensities ranging from 1019 up to 1021 W cm‑2. We discuss the nature of the interaction with respect to the solid case in which surface plasmon can be resonantly excited with weak laser intensity. In particular, we show the importance of the pulse duration and focalization of the laser beam on the amplitude of the SPW.

  15. Modes of occurrence of fluorine in the Late Paleozoic No. 6 coal from the Haerwusu Surface Mine, Inner Mongolia, China

    Energy Technology Data Exchange (ETDEWEB)

    Xibo Wang; Shifeng Dai; Yingying Sun; Dan Li; Weiguo Zhang; Yong Zhang; Yangbing Luo [China University of Mining and Technology, Beijing (China). State Key Laboratory of Coal Resources and Safe Mining

    2011-01-15

    The No. 6 coal from the Haerwusu Surface Mine, Inner Mongolia, China, is enriched in Al and Ga, which are valuable metal resources that could be extracted from fly ash. However, fluorine in the coal is unusually high (mean 286 {mu}g/g) and potentially toxic to the environment in the extraction process. In this paper, a sequential extraction/density separation procedure (SE/DS) was designed to examine the modes of occurrence of fluorine in the coal. The results show that fluorine extracted in distilled water, NH{sub 4}Ac (1 mol/l), and HCl (0.5%) leachates is low, and that in sulfide fraction is below the detection limit. The organic and silicate associations are inferred to account for more than 90% of the total fluorine in the coal. Boehmite and kaolinite are prime carriers of fluorine (the fluorine content in silicate fraction of the boehmite-enriched sample H-14 is up to 1906 {mu}g/g, and that of the kaolinite-enriched sample H-29 is 384 {mu}g/g). In bench samples H-2 and H-3, a minor amount of fluorine is related to goyazite. The relationship between fluorine and boehmite indicates that they were probably derived from the sediment source region, the weathered bauxite of the uplifted Benxi formation. 29 refs., 7 figs., 3 tabs.

  16. Application of Response Surface Methodology on Leaching of Iron from Partially Laterised Khondalite Rocks: A Bauxite Mining Waste

    Science.gov (United States)

    Swain, Ranjita; Bhima Rao, R.

    2017-08-01

    In the present investigation, response surface methodology (RSM) is used for a quadratic model that continuously controls the process parameters. This model is used to optimize the removal of iron oxide from Partially Laterised Khondalite (PLK) rocks which is influenced by several independent variables namely acid concentration, time and temperature. Second order response functions are produced for leaching of iron oxide from PLK rocks-a bauxite mining waste. In RSM, Box-Behnken design is used for the process optimization to achieve maximum removal of iron oxide. The influence of the process variables of leaching of iron oxide is presented in the form of 3-D response graphs. The results of this investigation reveals that 3 M hydrochloric acid concentration, 240 min time and 373 K temperature are found to be the best conditions for removal of 99% Fe2O3. The product obtain at this condition contain 80% brightness which is suitable for ceramic and filler industry applications. The novelity of the work is that the waste can be a value added product after suitable physical beneficiation and chemical treatment.

  17. Spatial distribution and source identification of heavy metals in surface soils in a typical coal mine city, Lianyuan, China.

    Science.gov (United States)

    Liang, Jie; Feng, Chunting; Zeng, Guangming; Gao, Xiang; Zhong, Minzhou; Li, Xiaodong; Li, Xin; He, Xinyue; Fang, Yilong

    2017-06-01

    In this study, we investigated the pollution degree and spatial distribution of heavy metals and determined their sources in topsoil in a typical coal mine city, Lianyuan, Hunan Province, China. We collected 6078 soil surface samples in different land use types. And the concentrations of Zn, Cd, Cu, Hg, Pb, Sb, As, Mo, V, Mn, Fe and Cr were measured. The average contents of all heavy metals were lower than their corresponding Grade II values of Chinese Soil Quality Standard with the exception of Hg. However, average contents of twelve heavy metals, except for Mn, exceeded their background level in soils in Hunan Province. Based on one-way analysis of variance (ANOVA), the contents of Cu, Zn, Cd, Pb, Hg, Mo and V were related to the anthropogenic source and there were statistically significant differences in their concentrations among different land use patterns. The spatial variation of heavy metal was visualized by GIS. The PMF model was used to ascertain contamination sources of twelve heavy metals and apportion their source contributions in Lianyuan soils. The results showed that the source contributions of the natural source, atmospheric deposition, industrial activities and agricultural activities accounted for 33.6%, 26.05%, 23.44% and 16.91%, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Airborne Lidar Simulator for the Lidar Surface Topography (LIST) Mission

    Science.gov (United States)

    Yu, Anthony W.; Krainak, Michael A.; Abshire, James B.; Cavanaugh, John; Valett, Susan; Ramos-Izquierdo, Luis

    2010-01-01

    In 2007, the National Research Council (NRC) completed its first decadal survey for Earth science at the request of NASA, NOAA, and USGS. The Lidar Surface Topography (LIST) mission is one of fifteen missions recommended by NRC, whose primary objectives are to map global topography and vegetation structure at 5 m spatial resolution, and to acquire global surface height mapping within a few years. NASA Goddard conducted an initial mission concept study for the LIST mission in 2007, and developed the initial measurement requirements for the mission.

  19. Molecular dynamics simulations study of nano bubble attachment at hydrophobic surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Jiaqi; Dang, Liem X.; Miller, Jan D.

    2018-01-01

    Bubble attachment phenomena are examined using Molecular Dynamics Simulations (MDS) for the first time. The simulation involves a nitrogen nano bubble containing 906 nitrogen molecules in a water phase with 74,000 water molecules at molybdenite surfaces. During a simulation period of 1 ns, film rupture and displacement occurs. The attached nanobubble at the hydrophobic molybdenite face surface results in a contact angle of about 90º. This spontaneous attachment is due to a “water exclusion zone” at the molybdenite face surface and can be explained by a van der Waals (vdW) attractive force, as discussed in the literature. In contrast, the film is stable at the hydrophilic quartz (001) surface and the bubble does not attach. Contact angles determined from MD simulations are reported, and these results agree well with experimental and MDS sessile drop results. In this way, film stability and bubble attachment are described with respect to interfacial water structure for surfaces of different polarity. Interfacial water molecules at the hydrophobic molybdenite face surface have relatively weak interactions with the surface when compared to the hydrophilic quartz (001) surface, as revealed by the presence of a 3 Å “water exclusion zone” at the molybdenite/water interface. The molybdenite armchair-edge and zigzag-edge surfaces show a comparably slow process for film rupture and displacement when compared to the molybdenite face surface, which is consistent with their relatively weak hydrophobic character.

  20. Mineralogy and geochemistry of boehmite-rich coals: New insights from the Haerwusu Surface Mine, Jungar Coalfield, Inner Mongolia, China

    Science.gov (United States)

    Dai, S.; Li, D.; Chou, C.-L.; Zhao, L.; Zhang, Y.; Ren, D.; Ma, Y.; Sun, Y.

    2008-01-01

    Boehmite-rich coal of Pennsylvanian age was discovered earlier at the Heidaigou Surface Mine, Jungar Coalfield, Inner Mongolia, China. This paper reports new results on 29 bench samples of the no. 6 coal from a drill core from the adjacent Haerwusu Surface Mine, and provides new insights into the origin of the minerals and elements present. The results show that the proportion of inertinite in the no. 6 coal is higher than in other Late Paleozoic coals in northern China. Based on mineral proportions (boehmite to kaolinite ratio) and major element concentrations in the coal benches of the drill core, the no. 6 coal may be divided into five sections (I to V). Major minerals in Sections I and V are kaolinite. Sections II and IV are mainly kaolinite with a trace of boehmite, and Section III is high in boehmite. The boehmite is derived from bauxite in the weathered surface (Benxi Formation) in the sediment-source region. The no. 6 coal is rich in Al2O3 (8.89%), TiO2 (0.47%), Li (116????g/g), F (286????g/g), Ga (18????g/g), Se (6.1????g/g), Sr (350????g/g), Zr (268????g/g), REEs (172????g/g), Pb (30????g/g), and Th (17????g/g). The elements are classified into five associations by cluster analysis, i.e. Groups A, B, C, D, and E. Group A (ash-SiO2-Al2O3-Na2O-Li) and Group B (REE-Sc-In-Y-K2O-Rb-Zr-Hf-Cs-U-P2O5-Sr-Ba-Ge) are strongly correlated with ash yield and mainly have an inorganic affinity. The elements that are negatively or less strongly correlated with ash yield (with exceptions of Fe2O3, Be, V, and Ni) are grouped in the remaining three associations: Group C, Se-Pb-Hg-Th-TiO2-Bi-Nb-Ta-Cd-Sn; Group D, Co-Mo-Tl-Be-Ni-Sb-MgO-Re-Ga-W-Zn-V-Cr-F-Cu; and Group E, S-As-CaO-MnO-Fe2O3. Aluminum is mainly distributed in boehmite, followed by kaolinite. The high correlation coefficients of the Li-ash, Li-Al2O3, and Li-SiO2 pairs indicate that Li is related to the aluminosilicates in the coal. The boehmite-rich coal is high in gallium and F, which occur in boehmite and the

  1. Mineralogy and geochemistry of boehmite-rich coals: New insights from the Haerwusu Surface Mine, Jungar Coalfield, Inner Mongolia, China

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Shifeng [State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, Beijing 100083 (China); Department of Resources and Earth Science, China University of Mining and Technology, Beijing 100083 (China); Li, Dan; Zhao, Lei; Zhang, Yong; Ma, Yuwen; Sun, Yingying [Department of Resources and Earth Science, China University of Mining and Technology, Beijing 100083 (China); Chou, Chen-Lin [Illinois State Geological Survey (Emeritus), 615 East Peabody Drive, Champaign, IL 61820 (United States); Ren, Deyi [State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, Beijing 100083 (China)

    2008-05-07

    Boehmite-rich coal of Pennsylvanian age was discovered earlier at the Heidaigou Surface Mine, Jungar Coalfield, Inner Mongolia, China. This paper reports new results on 29 bench samples of the no. 6 coal from a drill core from the adjacent Haerwusu Surface Mine, and provides new insights into the origin of the minerals and elements present. The results show that the proportion of inertinite in the no. 6 coal is higher than in other Late Paleozoic coals in northern China. Based on mineral proportions (boehmite to kaolinite ratio) and major element concentrations in the coal benches of the drill core, the no. 6 coal may be divided into five sections (I to V). Major minerals in Sections I and V are kaolinite. Sections II and IV are mainly kaolinite with a trace of boehmite, and Section III is high in boehmite. The boehmite is derived from bauxite in the weathered surface (Benxi Formation) in the sediment-source region. The no. 6 coal is rich in Al{sub 2}O{sub 3} (8.89%), TiO{sub 2} (0.47%), Li (116 {mu}g/g), F (286 {mu}g/g), Ga (18 {mu}g/g), Se (6.1 {mu}g/g), Sr (350 {mu}g/g), Zr (268 {mu}g/g), REEs (172 {mu}g/g), Pb (30 {mu}g/g), and Th (17 {mu}g/g). The elements are classified into five associations by cluster analysis, i.e. Groups A, B, C, D, and E. Group A (ash-SiO{sub 2}-Al{sub 2}O{sub 3}-Na{sub 2}O-Li) and Group B (REE-Sc-In-Y-K{sub 2}O-Rb-Zr-Hf-Cs-U-P{sub 2}O{sub 5}-Sr-Ba-Ge) are strongly correlated with ash yield and mainly have an inorganic affinity. The elements that are negatively or less strongly correlated with ash yield (with exceptions of Fe{sub 2}O{sub 3}, Be, V, and Ni) are grouped in the remaining three associations: Group C, Se-Pb-Hg-Th-TiO{sub 2}-Bi-Nb-Ta-Cd-Sn; Group D, Co-Mo-Tl-Be-Ni-Sb-MgO-Re-Ga-W-Zn-V-Cr-F-Cu; and Group E, S-As-CaO-MnO-Fe{sub 2}O{sub 3}. Aluminum is mainly distributed in boehmite, followed by kaolinite. The high correlation coefficients of the Li-ash, Li-Al{sub 2}O{sub 3}, and Li-SiO{sub 2} pairs indicate that Li is related to

  2. Simulating Supercapacitors: Can We Model Electrodes As Constant Charge Surfaces?

    Science.gov (United States)

    Merlet, Céline; Péan, Clarisse; Rotenberg, Benjamin; Madden, Paul A; Simon, Patrice; Salanne, Mathieu

    2013-01-17

    Supercapacitors based on an ionic liquid electrolyte and graphite or nanoporous carbon electrodes are simulated using molecular dynamics. We compare a simplified electrode model in which a constant, uniform charge is assigned to each carbon atom with a realistic model in which a constant potential is applied between the electrodes (the carbon charges are allowed to fluctuate). We show that the simulations performed with the simplified model do not provide a correct description of the properties of the system. First, the structure of the adsorbed electrolyte is partly modified. Second, dramatic differences are observed for the dynamics of the system during transient regimes. In particular, upon application of a constant applied potential difference, the increase in the temperature, due to the Joule effect, associated with the creation of an electric current across the cell follows Ohm's law, while unphysically high temperatures are rapidly observed when constant charges are assigned to each carbon atom.

  3. Fluvial transport and surface enrichment of arsenic in semi-arid mining regions: examples from the Mojave Desert, California

    Science.gov (United States)

    Kim, Christopher S.; Slack, David H.; Rytuba, James J.

    2012-01-01

    As a result of extensive gold and silver mining in the Mojave Desert, southern California, mine wastes and tailings containing highly elevated arsenic (As) concentrations remain exposed at a number of former mining sites. Decades of weathering and erosion have contributed to the mobilization of As-enriched tailings, which now contaminate surrounding communities. Fluvial transport plays an intermittent yet important and relatively undocumented role in the migration and dispersal of As-contaminated mine wastes in semi-arid climates. Assessing the contribution of fluvial systems to tailings mobilization is critical in order to assess the distribution and long-term exposure potential of tailings in a mining-impacted environment. Extensive sampling, chemical analysis, and geospatial mapping of dry streambed (wash) sediments, tailings piles, alluvial fans, and rainwater runoff at multiple mine sites have aided the development of a conceptual model to explain the fluvial migration of mine wastes in semi-arid climates. Intense and episodic precipitation events mobilize mine wastes downstream and downslope as a series of discrete pulses, causing dispersion both down and lateral to washes with exponential decay behavior as distance from the source increases. Accordingly a quantitative model of arsenic concentrations in wash sediments, represented as a series of overlapping exponential power-law decay curves, results in the acceptable reproducibility of observed arsenic concentration patterns. Such a model can be transferable to other abandoned mine lands as a predictive tool for monitoring the fate and transport of arsenic and related contaminants in similar settings. Effective remediation of contaminated mine wastes in a semi-arid environment requires addressing concurrent changes in the amounts of potential tailings released through fluvial processes and the transport capacity of a wash.

  4. Experiment on the treatment of acid mine drainage with optimized biomedical stone particles by response surface methodology.

    Science.gov (United States)

    Di, Junzhen; Wang, Mingxin; Zhu, Zhitao

    2018-03-01

    The immobilized particles were used to treat acid mine drainage (AMD) in the study, which owns the characteristics of serious pollution and high managing cost. The immobilized particles were prepared with sulfate reducing bacteria (SRB) and medical stones. In order to investigate the interactive influence of medical stones on the particle properties, the salt modification condition, content, and size of the medical stone were taken as the influential factors. At the same time, the removal rate of SO 4 2- and Mn 2+ , the release of total irons (TFe) and chemical oxygen demand (COD) and pH value were taken as the response values in the experiment. On the basis of the orthogonal experimental research, a response surface model was established. The experimental analysis showed that the particles can get the best treatment effect, when using the salt-modified medical stone with the content of 15% and particle size of 200~300 mesh. At this time, the removal rates of Mn 2+ and SO 4 2- in wastewater were 83.10 and 96.22%, respectively. The release contents of TFe and COD were 2.99 mg L -1 and 1828.54 mg L -1 , respectively, and the pH value was 7.05. Then, biological medical stone particles were prepared according to the optimal ratio in the response surface experiment. The adaptability of biomedical stone particles was studied at different concentrations of SO 4 2- , Mn 2+ and pH value. The results showed that the high concentration of SO 4 2- inhibited the metabolism of SRB, while Mn 2+ had a less effect. The biomedical stone particles could regulate pH value very well.

  5. Assessment of radioactive materials and heavy metals in the surface soil around uranium mining area of Tongliao, China.

    Science.gov (United States)

    Haribala; Hu, Bitao; Wang, Chengguo; Gerilemandahu; Xu, Xiao; Zhang, Shuai; Bao, Shanhu; Li, Yuhong

    2016-08-01

    Natural and artificial radionuclides and heavy metals in the surface soil of the uranium mining area of Tongliao, China, were measured using gamma spectrometry, flame atomic absorption spectrophotometry, graphite furnace atomic absorption spectrophotometry and microwave dissolution atomic fluorescence spectrometry respectively. The estimated average activity concentrations of (238)U, (232)Th, (226)Ra, (40)K and (137)Cs are 27.53±16.01, 15.89±5.20, 12.64±4.27, 746.84±38.24 and 4.23±4.76Bq/kg respectively. The estimated average absorbed dose rate in the air and annual effective dose rate are 46.58±5.26nGy/h and 57.13±6.45μSv, respectively. The radium equivalent activity, external and internal hazard indices were also calculated and their mean values are within the acceptable limits. The heavy metal concentrations of Pb, Cd, Cu, Zn, Hg and As from the surface soil were measured and their health risks were then determined. Although the content of Cd is much higher than the average background in China, its non-cancer and cancer risk indices are all within the acceptable ranges. These calculated hazard indices to estimate the potential radiological health risk in soil and the dose rate are well below their permissible limit. In addition the correlations between the radioactivity concentrations of the radionuclides and the heavy metals in soil were determined by the Pearson linear coefficient. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Simulation of triple junction motion with arbitrary surface tensions

    Czech Academy of Sciences Publication Activity Database

    Shofianah, N.; Muhammad, R. Z.; Švadlenka, Karel

    2015-01-01

    Roč. 45, č. 3 (2015), s. 235-244 ISSN 1992-9978 Institutional support: RVO:67985840 Keywords : triple junction motion * mean curvature flow * surface tension Subject RIV: BA - General Mathematics http://www.iaeng.org/IJAM/issues_v45/issue_3/IJAM_45_3_09.pdf

  7. Numerical simulation of floating bodies in extreme free surface waves

    Directory of Open Access Journals (Sweden)

    Z. Z. Hu

    2011-02-01

    Full Text Available In this paper, we use the in-house Computational Fluid Dynamics (CFD flow code AMAZON-SC as a numerical wave tank (NWT to study wave loading on a wave energy converter (WEC device in heave motion. This is a surface-capturing method for two fluid flows that treats the free surface as contact surface in the density field that is captured automatically without special provision. A time-accurate artificial compressibility method and high resolution Godunov-type scheme are employed in both fluid regions (air/water. The Cartesian cut cell method can provide a boundary-fitted mesh for a complex geometry with no requirement to re-mesh globally or even locally for moving geometry, requiring only changes to cut cell data at the body contour. Extreme wave boundary conditions are prescribed in an empty NWT and compared with physical experiments prior to calculations of extreme waves acting on a floating Bobber-type device. The validation work also includes the wave force on a fixed cylinder compared with theoretical and experimental data under regular waves. Results include free surface elevations, vertical displacement of the float, induced vertical velocity and heave force for a typical Bobber geometry with a hemispherical base under extreme wave conditions.

  8. Radiation exchange between persons and surfaces for building energy simulations

    DEFF Research Database (Denmark)

    Vorre, Mette Havgaard; Jensen, Rasmus Lund; Dreau, Jerome Le

    2015-01-01

    Thermal radiation within buildings is a significant component of thermal comfort. Typically the methods applied for calculating view factors between a person and its building surfaces requires great computational time. This research developed a view factor calculation method suitable for building...

  9. Wintertime land surface characteristics in climatic simulations over ...

    Indian Academy of Sciences (India)

    Most of the surface characteristics show that major interplay between topography and western disturbances (WDs) takes place along the foothills rather than over the higher peaks of the western Himalayas. ... Present address: Hydrospheric Atmospheric Research Center (HyARC), Nagoya University, Nagoya, Japan.

  10. Modeling and simulation of the deformation process of PTFE flexiblestamps for nanoimprint lithography on curved surfaces

    DEFF Research Database (Denmark)

    Sonne, Mads Rostgaard; Smistrup, K.; Hannibal, Morten

    2015-01-01

    In the presented work, simulations of the deformation process of flexible stamps used for nanoimprint lithographron curved surfaces are presented. The material used for the flexible stamps was polytetrafluoroethylene (PTFE) whose material behavior was found to be viscoelastic-viscoplastic. This b......In the presented work, simulations of the deformation process of flexible stamps used for nanoimprint lithographron curved surfaces are presented. The material used for the flexible stamps was polytetrafluoroethylene (PTFE) whose material behavior was found to be viscoelastic...

  11. Design and simulation of the surface shape control system for membrane mirror

    Science.gov (United States)

    Zhang, Gengsheng; Tang, Minxue

    2009-11-01

    The surface shape control is one of the key technologies for the manufacture of membrane mirror. This paper presents a design of membrane mirror's surface shape control system on the basis of fuzzy logic control. The system contains such function modules as surface shape design, surface shape control, surface shape analysis, and etc. The system functions are realized by using hybrid programming technology of Visual C# and MATLAB. The finite element method is adopted to simulate the surface shape control of membrane mirror. The finite element analysis model is established through ANSYS Parametric Design Language (APDL). ANSYS software kernel is called by the system in background running mode when doing the simulation. The controller is designed by means of controlling the sag of the mirror's central crosssection. The surface shape of the membrane mirror and its optical aberration are obtained by applying Zernike polynomial fitting. The analysis of surface shape control and the simulation of disturbance response are performed for a membrane mirror with 300mm aperture and F/2.7. The result of the simulation shows that by using the designed control system, the RMS wavefront error of the mirror can reach to 142λ (λ=632.8nm), which is consistent to the surface accuracy of the membrane mirror obtained by the large deformation theory of membrane under the same condition.

  12. Molecular dynamics simulations on surface properties of silicon dioxide melts

    CERN Document Server

    Röder, A

    2000-01-01

    In the present thesis the surface properties of a silicon dioxide melt were studied. As first systems drops (i.e. sytems without periodic boundary conditions) of N=432, 1536, as well as 4608 atoms were considered. The second analyzed geometry corresponds to that of a thin film, i. e. periodic boundary conditions in x- and y-direction were present, while in z-direction one had a free surface. In this case a system of N=1152 atoms was considered. As model potential the two-body potential proposed by Beest, Kramer, and van Santen was applied. For both geometries five temperatures were considered, which lied in the range of 3000 K

  13. How do uncertainties in NCEP R2 and CFSR surface fluxes impact tropical ocean simulations?

    Science.gov (United States)

    Wen, Caihong; Xue, Yan; Kumar, Arun; Behringer, David; Yu, Lisan

    2017-11-01

    NCEP/DOE reanalysis (R2) and Climate Forecast System Reanalysis (CFSR) surface fluxes are widely used by the research community to understand surface flux climate variability, and to drive ocean models as surface forcings. However, large discrepancies exist between these two products, including (1) stronger trade winds in CFSR than in R2 over the tropical Pacific prior 2000; (2) excessive net surface heat fluxes into ocean in CFSR than in R2 with an increase in difference after 2000. The goals of this study are to examine the sensitivity of ocean simulations to discrepancies between CFSR and R2 surface fluxes, and to assess the fidelity of the two products. A set of experiments, where an ocean model was driven by a combination of surface flux components from R2 and CFSR, were carried out. The model simulations were contrasted to identify sensitivity to different component of the surface fluxes in R2 and CFSR. The accuracy of the model simulations was validated against the tropical moorings data, altimetry SSH and SST reanalysis products. Sensitivity of ocean simulations showed that temperature bias difference in the upper 100 m is mostly sensitive to the differences in surface heat fluxes, while depth of 20 °C (D20) bias difference is mainly determined by the discrepancies in momentum fluxes. D20 simulations with CFSR winds agree with observation well in the western equatorial Pacific prior 2000, but have large negative bias similar to those with R2 winds after 2000, partly because easterly winds over the central Pacific were underestimated in both CFSR and R2. On the other hand, the observed temperature variability is well reproduced in the tropical Pacific by simulations with both R2 and CFSR fluxes. Relative to the R2 fluxes, the CFSR fluxes improve simulation of interannual variability in all three tropical oceans to a varying degree. The improvement in the tropical Atlantic is most significant and is largely attributed to differences in surface winds.

  14. Modelling, simulating and optimizing boiler heating surfaces and evaporator circuits

    DEFF Research Database (Denmark)

    Sørensen, K.; Condra, T.; Houbak, Niels

    2003-01-01

    developed as a Differential-Algebraic-Equation system (DAE) and MATLAB has been applied for the integration of the models. In general MATLAB has proved to be very stable for these DAE systems. Experimental verification has been carried out at a full scale plant equipped with instrumentation to verify heat....... The dynamic model has been developed for the purpose of determining boiler material temperatures and heat transfer from the flue gas side to the water-/steam side in order to simulate the circulation in the evaporator circuit and hereby the water level fluctuations in the drum. The dynamic model has been...

  15. Mixture and method for simulating soiling and weathering of surfaces

    Science.gov (United States)

    Sleiman, Mohamad; Kirchstetter, Thomas; Destaillats, Hugo; Levinson, Ronnen; Berdahl, Paul; Akbari, Hashem

    2018-01-02

    This disclosure provides systems, methods, and apparatus related to simulated soiling and weathering of materials. In one aspect, a soiling mixture may include an aqueous suspension of various amounts of salt, soot, dust, and humic acid. In another aspect, a method may include weathering a sample of material in a first exposure of the sample to ultraviolet light, water vapor, and elevated temperatures, depositing a soiling mixture on the sample, and weathering the sample in a second exposure of the sample to ultraviolet light, water vapor, and elevated temperatures.

  16. Simulation of Surface Erosion on a Logging Road in the Jackson Demonstration State Forest

    Science.gov (United States)

    Teresa Ish; David Tomberlin

    2007-01-01

    In constructing management models for the control of sediment delivery to streams, we have used a simulation model of road surface erosion known as the Watershed Erosion Prediction Project (WEPP) model, developed by the USDA Forest Service. This model predicts discharge, erosion, and sediment delivery at the road segment level, based on a stochastic climate simulator...

  17. Initialization of high resolution surface wind simulations using NWS gridded data

    Science.gov (United States)

    J. Forthofer; K. Shannon; Bret Butler

    2010-01-01

    WindNinja is a standalone computer model designed to provide the user with simulations of surface wind flow. It is deterministic and steady state. It is currently being modified to allow the user to initialize the flow calculation using National Digital Forecast Database. It essentially allows the user to downscale the coarse scale simulations from meso-scale models to...

  18. Numerical investigation of turbomolecular pumps using the direct simulation Monte Carlo method with moving surfaces

    NARCIS (Netherlands)

    Versluis, R.; Dorsman, R.; Thielen, L.; Roos, M.E.

    2009-01-01

    A new approach for performing numerical direct simulation Monte Carlo (DSMC) simulations on turbomolecular pumps in the free molecular and transitional flow regimes is described. The chosen approach is to use surfaces that move relative to the grid to model the effect of rotors and stators on a gas

  19. Simulation and Measurement of Angle Resolved Reflectance from Black Si Surfaces

    DEFF Research Database (Denmark)

    Davidsen, Rasmus Schmidt; Wu, Kaiyu; Schmidt, Michael Stenbæk

    2015-01-01

    In this work angle-resolved reflectance from nanostructured Si surfaces realized by maskless RIE texturing has been simulated and measured. The simulation and experimental measurement data show the same trend. Experimentally a total reflectance below 1% for incident angles below 30o and specular...

  20. Simultaneous calibration of surface flow and baseflow simulations: A revisit of the SWAT model calibration framework

    Science.gov (United States)

    Accurate analysis of water flow pathways from rainfall to streams is critical for simulating water use, climate change impact, and contaminant transport. In this study, we developed a new scheme to simultaneously calibrate surface flow (SF) and baseflow (BF) simulations of Soil and Water Assessment ...

  1. Surface Wave Simulation and Processing with MatSeis

    Energy Technology Data Exchange (ETDEWEB)

    THOMPSON,BEVERLY D.; CHAEL,ERIC P.; YOUNG,CHRISTOPHER J.; WALTER,WILLIAM R.; PASYANOS,MICHAEL E.

    2000-08-07

    In order to exploit the information on surface wave propagation that is stored in large seismic event datasets, Sandia and Lawrence Livermore National Laboratories have developed a MatSeis interface for performing phase-matched filtering of Rayleigh arrivals. MatSeis is a Matlab-based seismic processing toolkit which provides graphical tools for analyzing seismic data from a network of stations. Tools are available for spectral and polarization measurements, as well as beam forming and f-k analysis with array data, to name just a few. Additionally, one has full access to the Matlab environment and any functions available there. Previously the authors reported the development of new MatSeis tools for calculating regional discrimination measurements. The first of these performs Lg coda analysis as developed by Mayeda and coworkers at Lawrence Livermore National Laboratory. A second tool measures regional phase amplitude ratios for an event and compares the results to ratios from known earthquakes and explosions. Release 1.5 of MatSeis includes the new interface for the analysis of surface wave arrivals. This effort involves the use of regionalized dispersion models from a repository of surface wave data and the construction of phase-matched filters to improve surface wave identification, detection, and magnitude calculation. The tool works as follows. First, a ray is traced from source to receiver through a user-defined grid containing different group velocity versus period values to determine the composite group velocity curve for the path. This curve is shown along with the upper and lower group velocity bounds for reference. Next, the curve is used to create a phase-matched filter, apply the filter, and show the resultant waveform. The application of the filter allows obscured Rayleigh arrivals to be more easily identified. Finally, after screening information outside the range of the phase-matched filter, an inverse version of the filter is applied to obtain a

  2. Improving precipitation simulation from updated surface characteristics in South America

    Science.gov (United States)

    Pereira, Gabriel; Silva, Maria Elisa Siqueira; Moraes, Elisabete Caria; Chiquetto, Júlio Barboza; da Silva Cardozo, Francielle

    2017-07-01

    Land use and land cover maps and their physical-chemical and biological properties are important variables in the numerical modeling of Earth systems. In this context, the main objective of this study is to analyze the improvements resulting from the land use and land cover map update in numerical simulations performed using the Regional Climate Model system version 4 (RegCM4), as well as the seasonal variations of physical parameters used by the Biosphere Atmosphere Transfer Scheme (BATS). In general, the update of the South America 2007 land use and land cover map, used by the BATS, improved the simulation of precipitation by 10 %, increasing the mean temporal correlation coefficient, compared to observed data, from 0.84 to 0.92 (significant at p Amazon deforestation arc; (2) around the Brazil-Bolivia border (in the Brazilian Pantanal wetlands); (3) in the Northeast region of Brazil; (4) in northwestern Paraguay; and (5) in the River Plate Basin, in Argentina. Moreover, the main precipitation differences between sensitivity and control experiments occurred during the rainy months in central-north South America (October to March). These were associated with a displacement in the South Atlantic convergence zone (SACZ) positioning, presenting a spatial pattern of alternated areas with higher and lower precipitation rates. These important differences occur due to the replacement of tropical rainforest for pasture and agriculture and the replacement of agricultural areas for pasture, scrubland, and deciduous forest.

  3. Characterization, modeling and simulation of fused deposition modeling fabricated part surfaces

    Science.gov (United States)

    Taufik, Mohammad; Jain, Prashant K.

    2017-12-01

    Surface roughness is generally used for characterization, modeling and simulation of fused deposition modeling (FDM) fabricated part surfaces. But the average surface roughness is not able to provide the insight of surface characteristics with sharp peaks and deep valleys. It deals in the average sense for all types of surfaces, including FDM fabricated surfaces with distinct surface profile features. The present research work shows that kurtosis and skewness can be used for characterization, modeling and simulation of FDM surfaces because these roughness parameters have the ability to characterize a surface with sharp peaks and deep valleys. It can be critical in certain application areas in tribology and biomedicine, where the surface profile plays an important role. Thus, in this study along with surface roughness, skewness and kurtosis are considered to show a novel strategy to provide new transferable knowledge about FDM fabricated part surfaces. The results suggest that the surface roughness, skewness and kurtosis are significantly different at 0° and in the range (0°, 30°], [30°, 90°] of build orientation.

  4. Control and evaluation methodology of reclaimed surfaces in coal mines; Metodologia para el Seguimiento y Evaluacion de Superficies Restauradas en Minas de Carbon

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    The objective of the project has been to establish a control and evaluation methodology of reclaimed surfaces in coal mines, ash dumps,... etc. to be applied especially in locations with limited availability of ton soil, and to be used by mining companies to establish an internal quality control of the reclamation carried out. This methodology has been developed based on the evaluation of the results obtained from the reclamation that Endesa carries out at the Puentes mine. An operating and simplified method which may be adopted by smaller sites has been developed. This project has been carried out during the period 1994-1996 and includes a study about the physicochemical conditions of reclaimed surfaces, soil organisms study and about vegetation productivity associated to micorrizae. The conclusions and recommendations obtained include reclamation techniques (study and management of the deposit dumped, top soil management, addition of basic correctors, fertilization, top soil and maintenance works) and reclaimed surface control techniques (physicochemical soil conditions, soil organisms and vegetation). (Author)

  5. Coupling of surface relaxation and polarization in PbTiO{sub 3} from atomistic simulation

    Energy Technology Data Exchange (ETDEWEB)

    Behera, R K; Sinnott, S B; Phillpot, S R [Department of Materials Science and Engineering, University of Florida, Gainesville, FL 32611 (United States); Hinojosa, B B; Asthagiri, A [Department of Chemical Engineering, University of Florida, Gainesville, FL 32611 (United States)], E-mail: sphil@mse.ufl.edu

    2008-10-01

    Molecular dynamics simulations are used to characterize ferroelectricity on the (001) surfaces of PbTiO{sub 3} (PT), one of the most widely studied ferroelectric materials. Two different empirical interatomic shell model potentials are used. Both PbO and TiO{sub 2} surface terminations in PT under open circuit electrical boundary conditions are characterized. The results are found to be in good agreement with the results of density functional theory calculations. The atomic relaxations, interlayer spacings and surface rumplings of each of the four possible surface terminations are analyzed. The deviation of the polarization from the bulk value is observed to be larger when the polarization points out of the surface than when it points into the surface. Analysis of the surface energies for free-standing films shows that polarization parallel to the surface is energetically more favorable than the polarization normal to the surfaces.

  6. Airborne Instrument Simulator for the Lidar Surface Topography (LIST) Mission

    Science.gov (United States)

    Yu, Anthony W.; Krainak, Michael A.; Harding, David J.; Abshire, James B.; Sun, Xiaoli; Cavanaugh, John; Valett, Susan; Ramos-Izquierdo, Luis

    2010-01-01

    In 2007, the National Research Council (NRC) completed its first decadal survey for Earth science at the request of NASA, NOAA, and USGS. The Lidar Surface Topography (LIST) mission is one of fifteen missions recommended by NRC, whose primary objectives are to map global topography and vegetation structure at 5 m spatial resolution, and to acquire global coverage with a few years. NASA Goddard conducted an initial mission concept study for the LIST mission 2007, and developed the initial measurement requirements for the mission.

  7. Simulation of an oil film at the sea surface and its radiometric properties in the SWIR

    Science.gov (United States)

    Schwenger, Frédéric; Van Eijk, Alexander M. J.

    2017-10-01

    The knowledge of the optical contrast of an oil layer on the sea under various surface roughness conditions is of great interest for oil slick monitoring techniques. This paper presents a 3D simulation of a dynamic sea surface contaminated by a floating oil film. The simulation considers the damping influence of oil on the ocean waves and its physical properties. It calculates the radiance contrast of the sea surface polluted by the oil film in relation to a clean sea surface for the SWIR spectral band. Our computer simulation combines the 3D simulation of a maritime scene (open clear sea/clear sky) with an oil film at the sea surface. The basic geometry of a clean sea surface is modeled by a composition of smooth wind driven gravity waves. Oil on the sea surface attenuates the capillary and short gravity waves modulating the wave power density spectrum of these waves. The radiance of the maritime scene is calculated in the SWIR spectral band with the emitted sea surface radiance and the specularly reflected sky radiance as components. Wave hiding and shadowing, especially occurring at low viewing angles, are considered. The specular reflection of the sky radiance at the clean sea surface is modeled by an analytical statistical bidirectional reflectance distribution function (BRDF) of the sea surface. For oil at the sea surface, a specific BRDF is used influenced by the reduced surface roughness, i.e., the modulated wave density spectrum. The radiance contrast of an oil film in relation to the clean sea surface is calculated for different viewing angles, wind speeds, and oil types characterized by their specific physical properties.

  8. Boundary Slip and Surface Interaction: A Lattice Boltzmann Simulation

    International Nuclear Information System (INIS)

    Yan-Yan, Chen; Hua-Bing, Li; Hou-Hui, Yi

    2008-01-01

    The factors affecting slip length in Couette geometry flows are analysed by means of a two-phase mesoscopic lattice Boltzmann model including non-ideal fluid-fluid and fluid-wall interactions. The main factors influencing the boundary slip are the strength of interactions between fluid-fluid and fluid-wall particles. Other factors, such as fluid viscosity, bulk pressure may also change the slip length. We find that boundary slip only occurs under a certain density (bulk pressure). If the density is large enough, the slip length will tend to zero. In our simulations, a low density layer near the wall does not need to be postulated a priori but emerges naturally from the underlying non-ideal mesoscopic dynamics. It is the low density layer that induces the boundary slip. The results may be helpful to understand recent experimental observations on the slippage of micro flows

  9. Simulating the Near-Surface Environments of Solar System Bodies in the Laboratory

    Science.gov (United States)

    Donaldson Hanna, K. L.; Bowles, N. E.; Greenhagen, B. T.

    2016-12-01

    Thermal infrared (TIR) emissivity measurements are sensitive to a planetary body's near-surface (upper hundreds of microns) environment, porosity and particle size, which make the interpretation of thermal infrared remote sensing observations of planetary surfaces challenging. Thus, well-constrained laboratory TIR measurements of analogue samples for a range of particle sizes, porosities and near-surface environments are needed. Near-surface environments and porosities for a range of solar system bodies can be simulated using facilities within University of Oxford's Planetary Spectroscopy Facility (PSF). The Simulated Lunar Environment Chamber (SLEC) within Oxford's PSF is a vacuum chamber capable of simulating near-surface conditions for a range of solar system bodies by varying atmospheric pressure and incident solar irradiation. By varying the near-surface environment, the thermal gradient in the upper hundreds of microns of the sample is varied, which can affect the position and contrast of diagnostic features in TIR spectra. The atmospheric pressure inside the chamber is varied between 1000, 5 and < 10-4 mbar to simulate Earth, Mars and airless bodies (e.g. the Moon, Mars' moons and asteroids) conditions. The solar-like irradiation is varied by adjusting the power of the halogen lamp until the brightness temperature of the sample is similar to the brightness temperature of the simulated planetary body. Varying the sample packing in the sample cup simulates a range of near-surface porosities. Here we present laboratory emissivity spectra of a suite of well-characterized rock, soil and mineral samples (< 25 mm in particle size) measured under a range of simulated planetary conditions including Earth, Mars, Moon and asteroids. These well-controlled laboratory measurements enable the interpretation of remote sensing observations, which help in determining a planet's surface composition as well as the consolidated nature of its regolith.

  10. Simulating Near-Surface Environments of Solar System Bodies in the Laboratory

    Science.gov (United States)

    Donaldson Hanna, Kerri; Bowles, Neil

    2017-04-01

    Thermal infrared (TIR) emissivity measurements are sensitive to a planetary body's near-surface (upper hundreds of microns) environment, porosity and particle size, which make the interpretation of thermal infrared remote sensing observations of planetary surfaces challenging. Thus, well-constrained laboratory TIR measurements of analogue samples for a range of particle sizes, porosities and near-surface environments are needed. Near-surface environments and porosities for a range of solar system bodies can be simulated using facilities within University of Oxford's Planetary Spectroscopy Facility (PSF). The Simulated Lunar Environment Chamber (SLEC) within Oxford's PSF is a vacuum chamber capable of simulating near-surface conditions for a range of solar system bodies by varying atmospheric pressure and incident solar irradiation. By varying the near-surface environment, the thermal gradient in the upper hundreds of microns of the sample is varied, which can affect the position and contrast of diagnostic features in TIR spectra. The atmospheric pressure inside the chamber is varied between 1000, 5 and < 10-4 mbar to simulate Earth, Mars and airless bodies (e.g. the Moon, Mars' moons and asteroids) conditions. The solar-like irradiation is varied by adjusting the power of the halogen lamp until the brightness temperature of the sample is similar to the brightness temperature of the simulated planetary body. Varying the sample packing in the sample cup simulates a range of near-surface porosities. Here we present laboratory emissivity spectra of a suite of well-characterized rock, soil and mineral samples (< 25 microns in particle size) measured under a range of simulated planetary conditions including Earth, Mars, Moon and asteroids. These well-controlled laboratory measurements enable the interpretation of remote sensing observations, which help in determining a planet's surface composition as well as the consolidated nature of its regolith.

  11. Molecular dynamics simulation of temperature effects on CF3+ etching of Si surface

    NARCIS (Netherlands)

    Ning, J. P.; Lu, X. D.; Zhao, C. L.; Qin, Y. M.; He, P. N.; Bogaerts, A.; Gou, F. J.

    2010-01-01

    Molecular dynamics method was employed to investigate the effects of the reaction layer formed near the surface region on CF3+ etching of Si at different temperatures. The simulation results show that the coverages of F and C are sensitive to the surface temperature. With increasing temperature, the

  12. External surface adsorption on silicalite-1 zeolite studied by molecular simulation

    NARCIS (Netherlands)

    Garcia-Perez, E.; Schnell, S.K.; Castillo, J.M.; Calero, S.; Kjelstrup, S.; Dubbeldam, D.; Vlugt, T.J.H.

    2011-01-01

    We have studied the adsorption of ethane, propane, and their mixtures on the external surface of silicalite-1 zeolite by molecular simulation using a classical force field. The ideal adsorbed solution theory (IAST) was successfully used to describe mixture adsorption, both on the external surface

  13. Intercomparison of oceanic and atmospheric forced and coupled mesoscale simulations Part I: Surface fluxes

    Directory of Open Access Journals (Sweden)

    P. Josse

    1999-04-01

    Full Text Available A mesoscale non-hydrostatic atmospheric model has been coupled with a mesoscale oceanic model. The case study is a four-day simulation of a strong storm event observed during the SEMAPHORE experiment over a 500 × 500 km2 domain. This domain encompasses a thermohaline front associated with the Azores current. In order to analyze the effect of mesoscale coupling, three simulations are compared: the first one with the atmospheric model forced by realistic sea surface temperature analyses; the second one with the ocean model forced by atmospheric fields, derived from weather forecast re-analyses; the third one with the models being coupled. For these three simulations the surface fluxes were computed with the same bulk parametrization. All three simulations succeed well in representing the main oceanic or atmospheric features observed during the storm. Comparison of surface fields with in situ observations reveals that the winds of the fine mesh atmospheric model are more realistic than those of the weather forecast re-analyses. The low-level winds simulated with the atmospheric model in the forced and coupled simulations are appreciably stronger than the re-analyzed winds. They also generate stronger fluxes. The coupled simulation has the strongest surface heat fluxes: the difference in the net heat budget with the oceanic forced simulation reaches on average 50 Wm-2 over the simulation period. Sea surface-temperature cooling is too weak in both simulations, but is improved in the coupled run and matches better the cooling observed with drifters. The spatial distributions of sea surface-temperature cooling and surface fluxes are strongly inhomogeneous over the simulation domain. The amplitude of the flux variation is maximum in the coupled run. Moreover the weak correlation between the cooling and heat flux patterns indicates that the surface fluxes are not responsible for the whole cooling and suggests that the response of the ocean mixed layer

  14. Intercomparison of oceanic and atmospheric forced and coupled mesoscale simulations Part I: Surface fluxes

    Directory of Open Access Journals (Sweden)

    H. Giordani

    Full Text Available A mesoscale non-hydrostatic atmospheric model has been coupled with a mesoscale oceanic model. The case study is a four-day simulation of a strong storm event observed during the SEMAPHORE experiment over a 500 × 500 km2 domain. This domain encompasses a thermohaline front associated with the Azores current. In order to analyze the effect of mesoscale coupling, three simulations are compared: the first one with the atmospheric model forced by realistic sea surface temperature analyses; the second one with the ocean model forced by atmospheric fields, derived from weather forecast re-analyses; the third one with the models being coupled. For these three simulations the surface fluxes were computed with the same bulk parametrization. All three simulations succeed well in representing the main oceanic or atmospheric features observed during the storm. Comparison of surface fields with in situ observations reveals that the winds of the fine mesh atmospheric model are more realistic than those of the weather forecast re-analyses. The low-level winds simulated with the atmospheric model in the forced and coupled simulations are appreciably stronger than the re-analyzed winds. They also generate stronger fluxes. The coupled simulation has the strongest surface heat fluxes: the difference in the net heat budget with the oceanic forced simulation reaches on average 50 Wm-2 over the simulation period. Sea surface-temperature cooling is too weak in both simulations, but is improved in the coupled run and matches better the cooling observed with drifters. The spatial distributions of sea surface-temperature cooling and surface fluxes are strongly inhomogeneous over the simulation domain. The amplitude of the flux variation is maximum in the coupled run. Moreover the weak correlation between the cooling and heat flux patterns indicates that the surface fluxes are not responsible for the whole cooling and suggests that the response of the ocean mixed layer

  15. Nuclear waste repository simulation experiments (brine migration), Asse Mine of the Federal of Germany: Quarterly brine migration data report, July-September 1984

    International Nuclear Information System (INIS)

    Coyle, A.J.; Kalia, H.N.; Eckert, J.L.

    1986-10-01

    The fifth brine migration data status report describes experiments simulating a nuclear waste repository at the 800-m (2624-ft) level of the Asse Salt Mine in the Federal Republic of Germany from May 1983 through September 1984. This report describes the test equipment, the Asse Salt Mine, and the pretest properties of the salt in the test gallery. This report also includes test data for the first 16 months of operations on brine migration rates, borehole pressure, salt temperatures, and thermomechanical behavior of the salt. Annual reports have been prepared for the years 1983 and 1984, describing the test activities on a yearly basis (Rothfuchs et al., 1984, 1986). The duration of the experiments will be approximately 2 years, ending in December 1985. 2 refs., 118 figs., 91 tabs

  16. Molecular Dynamics Simulations of Water Nanodroplets on Silica Surfaces

    DEFF Research Database (Denmark)

    Zambrano, Harvey A; Walther, Jens Honore; Jaffe, Richard L.

    2009-01-01

    and DNA microarrays technologies.4,5,6,7,8 Although extensive experimental, theoretical and computational work has been devoted to study the nature of the interaction between silica and water,2,9-16 at the molecular level a complete understanding of silica-water systems has not been reached. Contact angle...... computations of water droplets on silica surfaces offers a useful fundamental and quantitative measurement in order to study chemical and physical properties of water-silica systems.3,16,17,18 For hydrophobic systems the static and dynamic properties of the fluid-solid interface are influenced by the presence...... of air. Hence, nanobubles have been observed and proposed as the origin of long range ``hydrophobic'' forces19-30 even for hydrophilic silica-water interfaces unusual phenomena related to nanobubbles have been observed.31-33 In this work we study the role of air on the wetting of amorphous silica...

  17. Molecular Dynamics Simulations of Water Droplets On Hydrophilic Silica Surfaces

    DEFF Research Database (Denmark)

    Zambrano, Harvey A; Walther, Jens Honore; Jaffe, Richard L.

    2009-01-01

    of water droplets on silica surfaces offers a useful fundamental and quantitative measurement in order to study chemical and physical properties of water-silica systems. For hydrophobic systems the static and dynamic properties of the fluid-solid interface are influenced by the presence of air. Hence......Wetting is essential and ubiquitous in a variety of natural and technological processes. Silicon dioxides-water systems are abundant in nature and play fundamental roles in a vast variety of novel science and engineering activities such as silicon based devices, nanoscale lab on a chip systems...... and DNA microarrays technologies.Although extensive experimental, theoretical and computational work has been devoted to study the nature of the interaction between silica and water, at the molecular level a complete understanding of silica-water systems has not been reached. Contact angle computations...

  18. Single-molecule conductivity of non-redox and redox molecules at pure and gold-mined Au(111)-electrode surfaces

    DEFF Research Database (Denmark)

    Zhang, Jingdong; Chi, Qijin; Ulstrup, Jens

    media supported by comprehensive theoretical frames, have emerged as core approaches in these exciting areas. Single-molecule redox electrochemistry is rooted in two major areas. One is the preparation of well-defined (atomically planar) electrode surfaces modified by molecular monolayers (SAMs). High...... to surface-mined Au-atoms. In addition the SAMs ensure protein/enzyme immobilization gentle enough that the proteins retain electron transfer or enzyme activity in a variety of local environments. The second area is the mapping and control of the immobilized redox molecules and metalloproteins themselves...

  19. Molecular dynamics simulations of water on a hydrophilic silica surface at high air pressures

    DEFF Research Database (Denmark)

    Zambrano, H.A.; Walther, Jens Honore; Jaffe, R.L.

    2014-01-01

    of air in water at different pressures. Using the calibrated force field, we conduct MD simulations to study the interface between a hydrophilic silica substrate and water surrounded by air at different pressures. We find that the static water contact angle is independent of the air pressure imposed......Wepresent a force field forMolecular Dynamics (MD) simulations ofwater and air in contactwith an amorphous silica surface. We calibrate the interactions of each species present in the systemusing dedicated criteria such as the contact angle of a water droplet on a silica surface, and the solubility...... on the system. Our simulations reveal the presence of a nanometer thick layer of gas at the water–silica interface. We believe that this gas layer could promote nucleation and stabilization of surface nanobubbles at amorphous silica surfaces. © 2014 Elsevier B.V. All rights reserved....

  20. Chemical stability and surface stoichiometry of vanadium oxide phases studied by reactive molecular dynamics simulations

    Science.gov (United States)

    Jeon, Byoungseon; Ko, Changhyun; van Duin, Adri C. T.; Ramanathan, Shriram

    2012-02-01

    Compositional stability of various vanadium oxides and oxide growth on vanadium surfaces have been studied using reactive molecular dynamics simulation methods. Vanadium dioxide (VO2), sesquioxide (V2O3), pentoxide (V2O5), and hexavanadium tridecaoxide (V6O13) are studied in bulk crystalline and thin film structures, investigating charge distribution and pair distribution functions of particle interactions. The stability is estimated to be pentoxide, hexavanadium tridecaoxide, sesquioxide, and dioxide respectively in decreasing order in thin film structures. We then analyze oxide growth kinetics on vanadium (100) and (110) surfaces. The oxidation rate, stoichiometry, charge distribution, and the effect of surface orientation on kinetic phenomena are noted. In the early stages of surface oxidation of our simulation configurations, sesquioxide is found to be the dominant component. The modeling and simulation results are compared with experiments where available.