共查询到7条相似文献,搜索用时 0 毫秒
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S. S. D. FOSTER DSc CEng MICE FIGeol P. J. CHILTON MSc MIGeol MARIANNE E. STUART BSc 《Water and Environment Journal》1991,5(2):186-193
An increasing number of pesticide compounds are being detected in groundwater supplies worldwide. There has, nevertheless, been little research into the mechanisms by which such pollution occurs and the routes via which pesticides move from the land surface into aquifers. In view of the potential time-lag in the response of groundwater systems to pollution inputs, such knowledge is essential if the current situation is to be appraised adequately and if any necessary controls on pesticide use are to be introduced.
From basic data on the physicochemical properties of pesticide compounds and on groundwater flow and pollutant transport in the principal British aquifers, some useful observations can be made about the relative significance of different mechanisms of potential groundwater pollution. These mechanisms and their implications for field research on pesticide pollution of groundwater are discussed. This problem is compared and contrasted to that of nitrate pollution from agricultural land-use practices. 相似文献
From basic data on the physicochemical properties of pesticide compounds and on groundwater flow and pollutant transport in the principal British aquifers, some useful observations can be made about the relative significance of different mechanisms of potential groundwater pollution. These mechanisms and their implications for field research on pesticide pollution of groundwater are discussed. This problem is compared and contrasted to that of nitrate pollution from agricultural land-use practices. 相似文献
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阐述了在城市区域设立地下水非点源污染监测系统的重要性及作用,简单介绍了国外城市区域地下水水质监测系统的布置及成果,并提出了建立该系统的方法. 相似文献
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There is wide concern in developed countries that groundwater resources are deteriorating in the long-term, both in quantity and quality. Some causes of pollution have a largely agricultural origin of which nitrates and pesticides are thought to pose serious risks to human health. This paper briefly reviews the sources of agricultural pollution of groundwater and the extent of the problem. It summarizes the various processes which take place in aquifers to remove, alter or attenuate contaminants. 相似文献
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The serious pollution of groundwater under cities is demonstrated with data from Coventry (UK), Madras (India) and Birmingham (UK). Microbiological organisms, nitrates, and organic chemicals are common, but many other pollutants are also found. The main sources are industry and inadequate sewerage. The provision of sewerage must remain a priority, on health grounds, for cities in the developing world. Virtually all industrial sites pollute the soil and groundwater through careless handling of chemicals. Industrial sites should be treated like landfills: contained and carefully monitored. If industrialists had to use groundwater from below their own sites, they would suffer the consequences of any pollution. This would also clean up the aquifer by pumping out polluted water. 相似文献
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P. L. YOUNGER BSc MS PhD FGS R. MACKAY BSc B. J. CONNORTON BSc MSc FGS C. Geol 《Water and Environment Journal》1993,7(6):577-585
Integrated fieldwork and modelling has been undertaken to assess the vulnerability of riverside wells to pollution when river water is contaminated. Results highlight the importance of streambed sediments as a barrier to groundwater pollution by river water. The bed of the River Thames is lined with brown and grey organic-rich silts of low hydraulic conductivity (about 0.002 m/d). A 3-D model for solute transport in stream-aquifer systems was developed and applied to two riverside sites in the middle Thames valley. Model results indicate that well-water quality would only breach EC limits if the river was heavily polluted for a week or even a month (clearly an unlikely scenario). Sensitivity analyses showed the models to be far more sensitive to streambed parameters than to aquifer parameters. Thus it would be more sensible to focus fieldwork on the measurement of streambed properties than on the more usually measured aquifer parameters. 相似文献
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R. M. Davison MSc PhD D. N. Lerner MA MSc DIC CEng CGeol 《Water and Environment Journal》2000,14(6):419-426
The effluent from a former coal-carbonisation plant in Nottinghamshire has contaminated the underlying aquifer with ammonium and organic compounds. In terms of flow and contamination, the site has experienced a complex history. MODFLOW has been used to unravel the past flow directions and to provide a basis for solute transport and biodegradation modelling. The modelling has shown that a fine grid is required to represent local flows to prevent incorrect site interpretations. A telescopic mesh technique was essential for this study to enable the site features to be adequately represented while including the regional hydrogeological influences. The influence of grid size to numerical dispersion was investigated for the MT3D computer program. The 'method of characteristics'and 'hybrid method of characteristics'modules of MT3D were found to be relatively free from numerical dispersion for all the grid sizes investigated. However, the 'modified method of characteristics'suffered extensively, and a linear relationship between grid size and numerical dispersion was demonstrated for this complex model. 相似文献