NATURAL ARSENIC IN GROUNDWATER: OCCURRENCE, REMEDIATION AND MANAGEMENT - CHAPTER 25 ppt

... mining areas) and in some geothermal areas. There were also reports in the literature of arsenic occurring in some arid or semi-arid inland basins, for example in parts of Argentina and the United ... mortality, predominantly among infants, caused by diseases in surface waters in Bangladesh and other coun- tries. International aid agencies such as UNICEF became involved i...

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... 2002). 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 located ... 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 interflu...

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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 ... irrigation facil- ities and more than 60% of this irrigation water come from groundwater which is extracted by deep 119 Natural Arsenic in Groundwater: Occurrence, Remediation and...

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... precipitation of secondary sulfide minerals like mackinawite. This mineral is a precursor of pyrite and may incorporate some arsenic, acting as a sink for arsenic in ground- water where sulfate reduction ... 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...

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... reduction and growth Our investigations on As cycling in the mine tailings and shallow aquifers show several interest- ing results. First, in situ microorganisms play an important role in transforming ... medium sand, fine sand, silt, and clay. Aquifer sediments in the deep wells are mostly coarse sands, whereas the shallow wells usually consist of fine-to-medium grained sands....

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... 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 not explain why arsenic ... value always remains low in SW and SE region. Only mixing with oxygenated water or lack of reductant minerals can maintain the desired oxic condi- tion in SW and SE regions,...

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... oxyhydroxides noticed in the fine clastic sediments (Ahmed et al. 2001). 31 Natural Arsenic in Groundwater: Occurrence, Remediation and Management – Bundschuh, Bhattacharya and Chandrasekharam (eds) © ... the geo- chemical environment and weathering processes. Clay minerals can also bind elements in their interlayer and the binding capacity of clays directly depends...

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... imminent danger. Therefore to provide 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 ... sand-clay Sand-silty clay Gravel Coarse sand with gravel Sand Sand-silty clay Sukrauli Sukrauli Badera Badera Sand-silty clay Silty sand-clay Gravel mixed with silt Clay Rampurwa Rampurw...

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... 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 1 -7 δ 2 Η ‰ δ 18 Ο ‰ -1 0 -9 -8 y = 7.97x + 11.03 Figure 5. ... hydrological system, (2) to investigate the source(s) of 67 Natural Arsenic in Groundwater: Occurrence, Remediation and Management –...

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