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1.
SARAH L. LONGSTAFF BSc MSc FGS P. J. ALDOUS BSc PhD FGS L. CLARK BSc PhD CGeol R. J. FLAVIN BSc CGeol J. PARTINGTON 《Water and Environment Journal》1992,6(6):541-550
A detailed investigation of contamination by chlorinated solvents of the Chalk Aquifer underlying the towns of Luton and Dunstable was undertaken to assess the extent, causes and mechanisms of pollution. The research programme incorporated land-use surveys, regional groundwater surveys, monitoring of groundwater abstraction points and aquifer profiling by means of the drilling of observation boreholes, the analysis of the recovered core material and the depth sampling of these and other boreholes.
Low-level solvent contamination of the Chalk Aquifer was found to be widespread with 'hotspots'of higher concentrations. At the drilling sites, both the saturated and unsaturated zones were contaminated with solvents, although free product was not observed. The presence of an additional contaminant, oil, at some sites was noted to influence the distribution of solvents within the aquifer.
Clean-up of the aquifer is not a practical option, and treatment of the groundwater at the abstraction points has been adopted. 相似文献
Low-level solvent contamination of the Chalk Aquifer was found to be widespread with 'hotspots'of higher concentrations. At the drilling sites, both the saturated and unsaturated zones were contaminated with solvents, although free product was not observed. The presence of an additional contaminant, oil, at some sites was noted to influence the distribution of solvents within the aquifer.
Clean-up of the aquifer is not a practical option, and treatment of the groundwater at the abstraction points has been adopted. 相似文献
2.
As part of several groundwater investigations of the Permo-Triassic Sandstone aquifers in north west England, a detailed measurement of piezometric heads and groundwater flow within observation boreholes was made which showed that vertical differences of groundwater heads persist within aquifers. A number of case histories of these studies are presented, which are used to consider the impact of head variations on typical groundwater level and groundwater quality measurements taken in observation boreholes, with a view to recommending design criteria for observation boreholes and groundwater monitoring programmes. 相似文献
3.
There is an increasing need for engineered liners to prevent the escape of leachate and to control the migration of landfill gas. This has been influenced by new European and UK legislation and codes of practice.
General principles of site design are explained, followed by a review of the advantages and disadvantages of different liner systems, including mineral liners (natural clay, mudrocks and soil/bentonite admixtures), geomembranes and composite liners.
The need for conservative factors of safety in site design and high standards of quality control, involving full-time supervision and independent certification of the installation works, are considered essential to ensure the effectiveness of the barrier.
There is no one ideal liner material. Composite mineral/geomembrane liners provide the highest degree of security against leakage and, as such, should be considered as 'the norm'rather than for use only in particularly high-risk situations. 相似文献
General principles of site design are explained, followed by a review of the advantages and disadvantages of different liner systems, including mineral liners (natural clay, mudrocks and soil/bentonite admixtures), geomembranes and composite liners.
The need for conservative factors of safety in site design and high standards of quality control, involving full-time supervision and independent certification of the installation works, are considered essential to ensure the effectiveness of the barrier.
There is no one ideal liner material. Composite mineral/geomembrane liners provide the highest degree of security against leakage and, as such, should be considered as 'the norm'rather than for use only in particularly high-risk situations. 相似文献
4.
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
5.
P. K. Bishop BSc PhD CGeol FGS B. D. Misstear BA MSc CGeol FGS CEng MIEI M. White BSc CEng MICE N. J. Harding BSc 《Water and Environment Journal》1998,12(3):216-223
This paper summarizes the findings of a recent research project on groundwater contamination from leaking sewers, which was completed for the Construction Industry Research and Information Association. Fifty-four incidents were identified in England and Wales from a combined questionnaire survey and literature review. In addition to recorded incidents, the poor quality of many urban groundwaters suggests some effects from leaking sewers. Age is considered to be the most significant characteristic governing leakage from sewers; ground conditions (predominantly aquifer vulnerability) and usage (private versus public ownership) are also important factors relating to the likelihood of groundwater pollution from leaking sewers. Recommended strategies for reducing groundwater contamination include (a) modification of existing criteria for the service performance grading of existing sewers, (b) improved construction of new sewers in appropriate areas, (c) increased groundwater monitoring, and (d) risk assessments for new groundwater sources. 相似文献
6.
R. C. HARRIS MSc BSc CGeol FGS MIWM A. C. SKINNER PhD BSc CGeol FGS 《Water and Environment Journal》1992,6(6):569-574
The greatest threat of contamination to groundwater resources is posed by pollutants from diffuse sources, yet legislation in the UK has until recently been focused on point sources. The problem of widespread pollution from industrial sources is described and compared with that from agriculture. The legislative controls available under the Water Resources Act 1991 are outlined, and the approach adopted by the National Rivers Authority in its Groundwater Protection Policy is discussed with respect to the concept of groundwater vulnerability. 相似文献
7.
Groundwater Rebound in the Leicestershire Coalfield 总被引:2,自引:0,他引:2
J. Smith BSc MSc CGeol FGS J. J. Colls BSc PhD ARCS FRMetSoc 《Water and Environment Journal》1996,10(4):280-289
The Leicestershire coalfield has been mined for at least eight hundred years, the last deep mine closing in 1991. The earliest shallow mines on the exposed coalfield are not recorded on plan, but were later connected to the deeper workings in many seams. In order to protect the last deep mines, pumping was maintained from the abandoned mines to the north.
Water-table rebound was observed prior to closure, and is now affecting the surface. Increased emissions of poor-quality water into low-discharge surface water-courses are predicted. Renewed subsidence has implications for roads, services and property. Rising water levels will affect old opencast excavations and waste disposal sites.
Fieldwork and abandoned mine plan inspections have demonstrated renewed subsidence and evidence of increased emissions in those low-lying areas of the exposed coalfield which are believed to be most at risk. 相似文献
Water-table rebound was observed prior to closure, and is now affecting the surface. Increased emissions of poor-quality water into low-discharge surface water-courses are predicted. Renewed subsidence has implications for roads, services and property. Rising water levels will affect old opencast excavations and waste disposal sites.
Fieldwork and abandoned mine plan inspections have demonstrated renewed subsidence and evidence of increased emissions in those low-lying areas of the exposed coalfield which are believed to be most at risk. 相似文献
8.
A bout ONE THIRD of the population of the UK depends on groundwater, which is pumped mainly from the Cretaceous Chalk limestone and the Permo-Trias Bunter Sandstone, for their domestic supply. The recharge areas of both aquifers correspond broadly with areas of high population density and substantial industrial activity. The disposal of solid and liquid wastes which are generated by this large population has caused local contamination of groundwater, and there is evidence of trace concentrations of a large range of man-made organic substances in public supplies. Although total prevention of groundwater pollution is not feasible, it is increasingly evident that groundwater resources and quality management must involve improved waste-disposal management. This paper reviews the main threats, the ways in which the hazards and the resources should be monitored, and legislative changes which are desirable. The problems in the interpretation of data and the models used for prediction are also discussed. 相似文献
9.
S. S. D. Foster DSc CEng MICE CGeol FGS D. R. C. Grey MSc CGeol FGS 《Water and Environment Journal》1997,11(3):193-199
Sustainable groundwater management requires (a) maximizing the use of aquifer storage to reduce water-supply costs while limiting environmental impacts, and (b) maximizing groundwater protection to reduce water-supply treatment needs while not unduly restricting land-use activities. These key issues are evaluated from the experience of a recent and comprehensive national strategic study, involving detailed consultation with many stakeholders with an interest in groundwater resources. Such balances are not easy to achieve because groundwater systems are complex to analyse and slow to respond to change, resulting in considerable uncertainty in assessment and prediction without in-depth research and high-resolution monitoring. Current institutional and regulatory arrangements for the water sector in England and Wales do not appear to be achieving the best possible use of aquifer storage and optimal investment in groundwater protection. 相似文献
10.
S. E. BUSS BA MSc DIC GRSC FGS A. P BUTLER BSc MSc DIC PhD FRMet.S C. J SOLLARS BSc MSc DIC PhD R. PERRY BSc PhD DSc FEng FICE C.Chem FRSC FRSH MIWM P. M JOHNSTON BSc MSc DIC FGS 《Water and Environment Journal》1995,9(4):353-359
The introduction of synthetic lining materials for leachate containment and the prevention of groundwater contamination was an important development in landfill technology. These materials have a low hydraulic conductivity which results in minimal leachate release by bulk fluid flow (advection) provided that the barrier (and its construction) is free from defects. However, the effectiveness of these materials as barriers cannot be confirmed unless contaminant release by diffusion is also taken into consideration.
This paper reviews the mechanisms by which transport through barriers occur. It highlights the role of diffusion as a pathway for organic compounds to migrate through synthetic liners and indicates its importance in terms of environmental impact and landfill design. 相似文献
This paper reviews the mechanisms by which transport through barriers occur. It highlights the role of diffusion as a pathway for organic compounds to migrate through synthetic liners and indicates its importance in terms of environmental impact and landfill design. 相似文献