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Mine Sites (mine + site)
Selected AbstractsDecolonising, Multiplicities and Mining in the Eastern Goldfields, Western AustraliaGEOGRAPHICAL RESEARCH, Issue 1 2003Leah M. Gibbs In this ,postcolonial' era, peoples and places around the globe continue to face ongoing colonisation. Indigenous peoples in particular experience colonisation in numerous forms. Despite recent attempts to ,decolonise' indigenous spaces, hegemonic systems of production, governance and thinking often perpetuate colonial structures and relationships, resulting in further entrenched colonisation or ,deep colonising' (Rose, 1999). The interface between indigenous communities and the mining industry provides fertile ground for the tensions emerging between decolonising and deep colonising. Gold mining operations at Placer Dome's Granny Smith mine in the Eastern Goldfields of Western Australia present a valuable case study for examining this tension. Changes taking place at the mine site are decolonising in intent, though outcomes may be deep colonising in effect. Recent discussions among cultural geographers over meanings of place, Ollman's (1993) notion of vantage point and a broadly postcolonial literature inform consideration of this tension. Acknowledgment and incorporation of multiple vantage points into new resource management systems allows current hegemonic approaches to be rethought, and provides insights for the shift towards genuinely decolonising processes. [source] The measurement and modelling of rill erosion at angle of repose slopes in mine spoilEARTH SURFACE PROCESSES AND LANDFORMS, Issue 7 2008G. R. Hancock Abstract The process of rill erosion causes significant amounts of sediment to be moved in both undisturbed and disturbed environments and can be a significant issue for agriculture as well as mining lands. Rills also often develop very quickly (from a single rainfall event to a season) and can develop into gullies if sufficient runoff is available to continue their development. This study examines the ability of a terrestrial laser scanner to quantify rills that have developed on fresh and homogeneous mine spoil on an angle of repose slope. It also examines the ability of the SIBERIA erosion model to simulate the rill's spatial and temporal behaviour. While there has been considerable work done examining rill erosion on rehabilitated mine sites and agricultural fields, little work has been done to examine rill development at angle of repose sites. Results show that while the overall hillslope morphology was captured by the laser scanner, with the morphology of the rills being broadly captured, the characteristics of the rills were not well defined. The digital elevation model created by the laser scanner failed to capture the rill thalwegs and tops of the banks, therefore delineating a series of ill defined longitudinal downslope depressions. These results demonstrate that an even greater density of points is needed to capture sufficient rill morphology. Nevertheless, SIBERIA simulations of the hillslope demonstrated that the model was able to capture rill behaviour in both space and time when correct model parameters were used. This result provides confidence in the SIBERIA model and its parameterization. The results demonstrate the sensitivity of the model to changes in parameters and the importance of the calibration process. Copyright © 2007 John Wiley & Sons, Ltd. [source] Metal toxicity inferred from algal population density, heterotrophic substrate use, and fatty acid profile in a small streamENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 4 2000Robert B. Genter Abstract The purpose of this study was to examine relations between metal concentrations in periphyton and the abundance of algal species, heterotrophic use of 95 carbon sources, and phospholipid fatty acids (PLFA) of the periphyton in a small stream spanning a mine in Lemhi County, Idaho, USA. Two upstream, two mine, and two downstream sites were examined. Elevated concentrations of As and Cu at the mine sites were associated with communities that were depleted of diatoms and filamentous blue-green algae and characterized by a low-diversity community dominated by a single blue-green alga and patchy populations of the diatom Achnanthidium minutissimum and a filamentous green alga. Carbon source use and PLFA profiles provided a rapid assessment of stream conditions that were consistent with algal taxonomy and with our hypotheses constructed from previous reports on periphyton responses to metal stress. [source] Alluvial records of medieval and prehistoric tin mining on Dartmoor, southwest EnglandGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 3 2004Varyl R. Thorndycraft The role of tin mining in the society of prehistoric Dartmoor and its impact on the local landscape have long been discussed despite equivocal evidence for prehistoric mine sites. A fluvial geomorphological approach, using floodplain stratigraphy, combined with sediment geochemistry and mineralogy, was employed to identify prehistoric tin mining at the catchment scale. Waste sediment, released during hydraulic mining of alluvial tin deposits, caused downstream floodplain aggradation of sands with a diagnostic signature of elevated Sn concentration within the silt fraction. At a palaeochannel site in the Erme Valley, sediment aggradation buried datable peat deposits. A period of aggradation postdating cal. A.D. 1288,1389 is consistent with the 13th century peak in tin production identified in the documentary record. An earlier phase of aggradation, however, occurred between the 4th and 7th centuries A.D., providing evidence of late Roman or early Post Roman tin mining activity on Dartmoor. © 2004 Wiley Periodicals, Inc. [source] Simulating Seepage into Mine Shafts and Tunnels with MODFLOWGROUND WATER, Issue 3 2010Jacob Zaidel In cases when an equivalent porous medium assumption is suitable for simulating groundwater flow in bedrock aquifers, estimation of seepage into underground mine workings (UMWs) can be achieved by specifying MODFLOW drain nodes at the contact between water bearing rock and dewatered mine openings. However, this approach results in significant numerical problems when applied to simulate seepage into an extensive network of UMWs, which often exist at the mine sites. Numerical simulations conducted for individual UMWs, such as a vertical shaft or a horizontal drift, showed that accurate prediction of seepage rates can be achieved by either applying grid spacing that is much finer than the diameter/width of the simulated openings (explicit modeling) or using coarser grid with cell sizes exceeding the characteristic width of shafts or drifts by a factor of 3. Theoretical insight into this phenomenon is presented, based on the so-called well-index theory. It is demonstrated that applying this theory allows to minimize numerical errors associated with MODFLOW simulation of seepage into UMWs on a relatively coarse Cartesian grid. Presented examples include simulated steady-state groundwater flow from homogeneous, heterogeneous, and/or anisotropic rock into a vertical shaft, a horizontal drift/cross-cut, a ramp, two parallel drifts, and a combined system of a vertical shaft connected to a horizontal drift. [source] Adaptive restoration of sand-mined areas for biological conservationJOURNAL OF APPLIED ECOLOGY, Issue 1 2005JASON CUMMINGS Summary 1Adaptive management approaches to ecological restoration are current best practice. The usefulness of such an approach was tested in this study by implementing repeated experiments that examined restoration options for derelict sand mine sites dominated by Imperata cylindrica. Reclamation of degraded land that is dominated by I. cylindrica is a common problem throughout the tropics. 2Initially, the hypothesized barrier to regeneration was limited seedling establishment because of I. cylindrica competition. After burning the grassland, woody weed control and planting of seedlings were implemented in factorial combination. 3Seedling survival 28 months after planting averaged 26%, with < 1% of all seedlings establishing to a height > 1 m. The hypothesis that a transition barrier comprising solely biotic interactions restricted regeneration of native woody cover was rejected after seedlings and natural regeneration failed to thrive in this experiment. 4A revised hypothesis, that the transition barrier comprised a combination of abiotic limitations (soil deficiencies) and biotic interactions (Wallabia bicolor browsing and I. cylindrica competition), was developed. A second experiment tested this hypothesis by removing W. bicolor (fencing), slashing the I. cylindrica, adding organic mulch and planting a mixture of native pioneer and secondary successional woody species in factorial combination. 5Seedling survival was 61% in the second experiment and mulching significantly enhanced the survival and growth of all planted species. Planting alone reduced the regeneration of I. cylindrica after slashing. Native woody cover establishment was maximized by planting seedlings in mulched treatments. 6Synthesis and applications. Taken together, these experiments support the hypothesis that there is a barrier restricting regeneration of native woody cover, and the barrier probably comprises both abiotic and biotic components. By adopting an adaptive management approach to the ecological restoration of sites, significant insights into their management requirements have been gained, supporting the current best practice restoration framework. Insights gained through monitoring and adaptation will be used to update the reserve plan of management, enhancing restoration of this severely degraded area and promoting connectivity of native woody cover within the conservation estate. [source] Mediation of arsenic oxidation by Thiomonas sp. in acid-mine drainage (Carnoulès, France)JOURNAL OF APPLIED MICROBIOLOGY, Issue 3 2003O. Bruneel Abstract Aims: To isolate, identify, and characterize heterotrophic bacteria in acid-mine drainage that mediate oxidation of As(III). Methods and Results: Samples of acid-mine drainage were collected over a period of 14 months. Heterotrophic and non-obligatory acidophilic bacteria in the samples were cultured on a solid medium (pH 7·0,7·2), and three strains were isolated. The three different strains belong to the genus Thiomonas, and have more than 99% homology with the group Ynys1. Culturing in mineral media demonstrated that the isolated strains used thiosulphate as an energy source, and oxidized iron in the presence of thiosulphate. However, none of the strains were able to oxidize arsenic in the presence of thiosulphate, nor could they use iron or arsenic alone as an energy source. In vitro experiments demonstrated that two of the Thiomonas strains were able to oxidize more than 90% of the As(III) present in the acid-mine drainage, whereas no abiotic oxidation of arsenic occurred. Conclusions: Two strains of newly identified Thiomonas sp. found in acid-mine drainage are capable of oxidizing arsenic. Significance and Impact of Study: These results represent the first reported oxidation of arsenic by Thiomonas sp. Biologically mediated oxidation and subsequent immobilization of arsenic is of great interest for the remediation of contaminated mine sites. [source] Skills under threat: the case of HIV/AIDS in the mining industry in ZimbabweJOURNAL OF INTERNATIONAL DEVELOPMENT, Issue 5 2006Caroline N. Matangi Abstract The Zimbabwe mining industry is currently battling to arrest further spread of the HIV/AIDS crisis in workplaces, especially its impact on labour productivity. Labour in the closed community of mines has been greatly susceptible to HIV/AIDS infection. The current AIDS incidence in the mine sites is estimated at a weighted average of 15,per,cent amongst miners, with the largest category of workers,the 30,39 years age group,also constituting the worst affected category. Given the current state of the country's economy and consequently its adverse impact on the lifestyle of miners, the pandemic is expected to increase. This paper builds on the work of the ILO (1995) involving a survey of 18 various firms/institutions. The survey was carried out in Zambia in order to assess the impact of HIV/AIDS on the productive labour force. The survey revealed that many of the firms are experiencing irregular work attendance, ,wasted' training as some of the trained workers are constantly ill or die, high medical bills, funeral costs and reduced productivity and profits. An analysis of data on the main causes of death in 1993 shows that at least 61.8,per,cent of deaths could be attributed to causes that are very closely related to HIV/AIDS complications. Based on points highlighted by respondents and analysis of symptoms suffered, it was observed that HIV/AIDS tended to affect most general workers (36.8,per,cent), followed by the lower management (30.9,per,cent) and the middle management (20.6,per,cent). Comparatively, 11.8,per,cent of the deaths in 1993 belonged to the top management. Although it is hard to appreciate the meaning of the figures without knowledge of the number of people in each category, it nevertheless helps to form a clear picture of the impact of HIV/AIDS on industry. This paper seeks to further investigate the impact of HIV/AIDS on the productive labour force, by focusing on one particular industry,mining,using a blend of research methods to collect the data. This paper examines the impact of HIV/AIDS on the productive labour force and management responses. It forms part of the findings of data gathered in 2001 in the mining industry in Zimbabwe, to examine factors affecting management responses to HIV/AIDS in the mine sites. Zimbabwe is a country with a complex historical legacy of mine labour. This phenomenon can largely be attributed to the production oriented nature of the mining industry. Mines focus mainly on mineral extraction and as a result the bulk of mine workers tend to be production workers whose skills have developed over long periods of time. Production workers on mines have a tradition of long-term employment. This phenomenon has meant that labour in the mines is hard to replace as a result of skills, especially tacit knowledge, acquired over many years. Thus while the recent closure of some gold mines, largely due to low commodity prices, has meant that more miners are available in the labour market, this situation has not necessarily eased the process of replacing labour lost to the HIV/AIDS epidemic, as certain skills are firm specific. Production workers are predominantly male with the bulk falling in the 35,39 years age group. Most mine workers reside in mine villages, a colonial legacy that ensured miners were close to the workplace. The village system is a system of housing labourers, which demonstrates capitalistic methods of controlling labour and minimising costs. Of significance in this study's background is how the village system has come to be viewed as a factor in the spread of HIV/AIDS in the mining communities, because of its ,closed' nature. It is against this complex historical backdrop that the paper turns to examine the impact of the HIV/AIDS pandemic on production workers and management responses to the crisis using the Resource Based View of the Firm model (RBV), one of the theories in the Strategic Human Resource Management (SHRM) tradition. RBV was chosen for this study out of many HRM models that exist, because this theory, in particular, explains why it is advantageous for sites to use their ,unique' firm based resources in order to achieve sustainable competitive advantage. Given this rationale it was, therefore, presumed that this theory would best apply in mines battling with the adverse impact of HIV/AIDS on productivity, especially in the light of the harsh national economic climate, which would likely place limitations on response mechanisms. Further, the issue of firm-specific skills was also taken into consideration as an important factor in the mines, limiting their ability to resort to external solutions. Thus, given these factors, RBV was deemed the most appropriate model. The study finds that the pandemic depresses labour productivity through a number of significant ways: increased rate of HIV/AIDS induced absenteeism gradual labour turnover as a result of AIDS induced morbidity; and consequently declining skills availability, particularly firm-specific skills. Maintaining labour productivity in the face of gradually diminishing skills and indisposed labour will be key to softening the adverse economic consequences of the pandemic in the mines. To reduce the threat to labour productivity, mines must find ways of utilising, to the maximum extent practicable, existing skills. Results indicate that a move towards the utilisation of existing miners is the most favoured response mechanism in most mines. Utilising existing miners enables mines from spending financial resources on avoidable recruitment and training and quite often mechanisation, which may not necessarily be compatible with the old infrastructure in certain mines. Copyright © 2006 John Wiley & Sons, Ltd. [source] Wyoming Big Sagebrush Density: Effects of Seeding Rates and Grass CompetitionRESTORATION ECOLOGY, Issue 2 2002Mary I. Williams Abstract The mining industry commonly seeds shrubs and grasses concurrently on coal-mined lands of northeastern Wyoming, but ecological interactions between seeded shrubs and grasses are not well documented. Artemisia tridentata Nutt. ssp. wyomingensis (Beetle and Young) (Wyoming big sagebrush) is the dominant pre-mining shrub on many Wyoming mine sites. Despite past failures to establish Wyoming big sagebrush, the Wyoming Department of Environmental Quality, Land Quality Division's rules and regulations require establishment of 1 shrub per m2 on 20% of post-mined land in Wyoming. A study was established at the Belle Ayr Coal Mine south of Gillette, Wyoming to evaluate the effects of sagebrush seeding rates and grass competition on Wyoming big sagebrush seedling density. Three sagebrush seeding rates (1, 2, and 4 kg pure live seed [pls]/ha; 350, 700, and 1,400 pls/m2, respectively) and seven cool-season perennial grass mixture seeding rates (0, 2, 4, 6, 8, 10, and 14 kg pls/ha; 0, 187, 374, 561, 750, 935, and 1,309 pls/m2, respectively) were applied during winter 1998,1999. Pascopyrum smithii (Rydb.) A. Love (western wheatgrass), Elymus lanceolatus (Scribner & J.G. Smith) Gould (thickspike wheatgrass), and Elymus trachycaulus (Link) Gould ex Shinners (slender wheatgrass) comprised the grass seed mix (equal seed numbers of each species). Sagebrush seedling density differed among sagebrush seeding rates but not among grass seeding rates. On all sampling dates in 1999 and 2000, sagebrush seedling density differed among sagebrush rates and was greatest at the 4 kg pls/ha sagebrush seeding rate. All sagebrush seeding rates provided densities of at least 1 shrub per m2 after two growing seasons. Grass density and production in 2000 suggest that adequate grass production (75 g/m2) was achieved by seeding at 6 to 8 kg pls/ha. Within these grass seeding rates, four or more sagebrush seedlings per m2 were attained when sagebrush was seeded at 2 to 4 kg pls/ha. Use of these seeding rate combinations in mine reclamation can achieve Wyoming big sagebrush standards and reduce reseeding costs. [source] | ||||||||||||||||