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Geochemical assessment of groundwater quality in vicinity of Bhalswa landfill,Delhi, India,using graphical and multivariate statistical methods 总被引:1,自引:0,他引:1
A geochemical assessment of groundwater quality and possible contamination in the vicinity of the Bhalswa landfill site was
carried out by using a hydrochemical approach with graphical and multivariate statistical methods with the objective of identifying
the occurrence of various geochemical processes and understanding the impact of landfill leachates on groundwater quality.
Results indicate that nitrate, fluoride and heavy-metal pollution are in an alarming state with respect to the use of groundwater
for drinking purposes. Various graphical plots and statistical analyses have been applied to the chemical data based on the
ionic constituents, water types, and hydrochemical facies to infer the impact of the landfill on groundwater quality. The
statistical analysis and spatial and temporal variations indicate the leaching of contaminants from the landfill to the groundwater
aquifer system. The concentrations of heavy metals in the landfill leachates are as follows: Fe (22 mg/l), Mn (~20 mg/l),
Cu (~10 mg/l), Pb (~2 mg/l), Ni (0.25 mg/l), Zn (~10 mg/l), Cd (~0.2 mg/l), Cl− (~4,000 mg/l), SO42− (~3,320 mg/l), PO43− (~4 mg/l), NO3− (30 mg/l) and fluoride (~50 mg/l); all were much higher than the standards. The study reveals that the landfill is in a depleted
phase and is affecting groundwater quality in its vicinity and the surrounding area due to leaching of contaminants. 相似文献
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Two waste-disposal sites (old and new) in Calabar Municipality, SE Nigeria were evaluated to assess their suitability as
landfill sites and their impact on the groundwater. The field investigation included surface geological/hydrogeological and
geochemical studies. Leachate and groundwater were sampled and analysed for 3 months (April, May and June, 1997) for geochemical
characterisation. The results indicate that the two waste-disposal sites in the Calabar Municipality do not meet the requirements
as landfill sites. Physico-chemical analyses for temperature, pH, conductivity, dissolved oxygen, biological oxygen demand
after 5 days of incubation (BOD5), sulphate, nitrates, nitrite, trace and major elements in the leachate known to impact human health and the environment,
indicate high levels of pollution. The values for groundwater in the vicinity of the disposal sites were found to be within
the World Health Organisation (WHO) permissible limit.
Received: 29 March 1999 · Accepted: 3 January 2000 相似文献
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Reductive Dehalogenation of Chlorinated Hydrocarbons during Anaerobic Stabilization of Municipal Wastes During sequential anaerobic digestion of municipal wastes, distinct biogeochemical phases exist which show different capabilities to transform halogenated hydrocarbons. Chlorophenols, tetrachloroethylene, and chloroanilines codisposed together with organic-rich waste substrates are reductively dehalogenated during methanogenic conditions. Lindane is degraded during acidogenesis as well as during methanogenesis. However, degradation in methanogenic leachates is faster by a factor of 10. The poor transformation potential during acidogenesis compared to subsequent transient methanogenic and stabile methanogenic phases cannot be explained by inadequate acclimation of prevailing microorganisms to the codisposed organochlorines. Thus, observed transformation capabilities are a pertinent feature of methanogenic leachates, probably due to prevailing low redox potential and/or presence of suitable microbial activities (not necessarily methanogenis). Dehalogenation of 2,3,4,6-tetrachlorophenol as a model compound is hampered in methanogenic leachate by addition of a surplus of sulfate and is completely suppressed by addition of molybdate which selectively inhibits sulfate reducing microorganisms. Competition for common electron donators (e.g. H2) is discussed as an explanation of these results. The results point to sulfate reducing microorganisms being involved in reductive dehalogenation of chlorophenols. 相似文献
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