NATURAL ARSENIC IN GROUNDWATER: OCCURRENCE, REMEDIATION AND MANAGEMENT - CHAPTER 20 pptx

... that introduction of organic carbon by over-pumping of irrigation wells can be a factor in increasing arsenic mobility in shal- low groundwater in Bangladesh (Roach 200 4). Organic carbon in the ... dur- ing pumping. But arsenic contaminated wells do not show any concentration gradient during pumping in Bangladesh. In addition, the oxidation theory of arsenic release can no...

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... (Acharyya 200 2). 2 ARSENIC AFFECTED FLOOD-DELTA PLAINS IN WEST BENGAL Pandemic arsenic contamination in the Bengal Basin is essentially confined to the low-lying Ganga-Brahmaputra flood-delta plain ... Holocene entrenched floodplain in parts of lower-middle Gangetic plain in Bihar and eastern UP. Sediment cover on Pleistocene uplands in the Bengal Basin as well as, in inte...

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... local drinking water standard of 50␮g/L. The first symptoms of arsenic related diseases were detected in 1983 within the counties of La Banda and Robles, and in the fol- lowing year investigations ... pat- terns and remediation with natural materials. Master Thesis, Dept. of Land and Wat. Res. Eng., KTH, Stockholm, Sweden, TRITA-LWR-EX-0 3-0 5, 59p. Martin, A. 1999. Hidrog...

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... nutrient recycling process. This is obviously a major concern vis-a-vis soil pollution and contamination of the food chain through water-soil-crop transfer of contaminants. This demands special ... phases of incubation (Fig. 2). It is apparent that the algae growing on As-contaminated water and bioaccumulating it subsequently released the element in soil during the process of mineraliza...

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... Ϫ0.018 ϽϪ0.254 1.55 Similarity HCO 3 - CI - Na + NO - 3 Mn Fe tot PO 4 3- K + pH SO 4 2- Mg 2+ Ca 2+ EC As tot 0 -1 00 -2 00 -3 00 -4 00 -5 00 -6 00 -7 00 -8 00 12345678 91011121314 Figure 5. Results of Hierarchical ... precipitation of secondary sulfide minerals like mackinawite. This mineral is a precursor of pyrite and may incorporate some ars...

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... noticed in the fine clastic sediments (Ahmed et al. 200 1). 31 Natural Arsenic in Groundwater: Occurrence, Remediation and Management – Bundschuh, Bhattacharya and Chandrasekharam (eds) © 200 5, ... the geo- chemical environment and weathering processes. Clay minerals can also bind elements in their interlayer and the binding capacity of clays directly depends on...

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... concentration in groundwater (based on Tandukar et al. 200 1). Clay Sand Sand-silty clay Gravel Clay Gravel Sunawal Sunawal Silty sand-clay Sand-silty clay Gravel Coarse sand with gravel Sand Sand-silty ... uniform flow of information, IEC and training mater- ials that are suitable in the context of Nepal have already been printed and are being distributed in the hot spot areas. Si...

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... hydrological system, (2) to investigate the source(s) of 67 Natural Arsenic in Groundwater: Occurrence, Remediation and Management – Bundschuh, Bhattacharya and Chandrasekharam (eds) © 200 5, Taylor & ... geochemical conditions (an oxidizing environment with neutral pH) that suggest significant immobilization by 73 -7 5 -7 0 -6 5 -6 0 -5 5 -5 0 -1...

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... composition the water characterization in the aquifer of the study area fit into the three main types, viz. Na-(K)-Cl-SO 4 , Ca-(Mg)-Na-(K)-SO 4 and Ca-(Mg)-Na-(K)-HCO 3 das reported by the earlier ... previous study in which high levels of arsenic were obtained in the soils collected 85 Natural Arsenic in Groundwater: Occurrence, Remediation and Management – Bunds...

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... 95 Natural Arsenic in Groundwater: Occurrence, Remediation and Management – Bundschuh, Bhattacharya and Chandrasekharam (eds) © 200 5, Taylor & Francis Group, London, ISBN 04 1536 700 X Arsenic ... Naidu, R. 200 1. The possible contamination from arsenic through the food chain. In Groundwater Arsenic Contamination in the Bengal Delta Plains of Bangladesh (Pr...

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