TAILIEUCHUNG - High arsenic concentration in groundwater related to sedimentary facies in the Mekong River Delta, Vietnam

Arsenic (As) contamination in groundwater has been recognized in the Mekong River Delta (MRD) since 2001, especially in Dong Thap and An Giang provinces. The investigations were carried out during 2008-2009 and from 2012 to present. The investigations of As distribution in groundwater and sediments were based upon the field, and laboratory analyses using field kit (Hironaka, 1998) and AOAC laboratory - Vietnamese standard 6626-2000 (Vilas). | Vietnam Journal of Earth Sciences, 38(2), 178-187, DOI: Vietnam Academy of Science and Technology (VAST) Vietnam Journal of Earth Sciences High arsenic concentration in groundwater related to sedimentary facies in the Mekong River Delta, Vietnam Ta Thi Kim Oanh*, Nguyen Van Lap Institute of Resources Geography, Vietnam Academy of Science and Technology Received 18 January 2016. Accepted 01 June 2016 ABSTRACT Arsenic (As) contamination in groundwater has been recognized in the Mekong River Delta (MRD) since 2001, especially in Dong Thap and An Giang provinces. The investigations were carried out during 2008-2009 and from 2012 to present. The investigations of As distribution in groundwater and sediments were based upon the field, and laboratory analyses using field kit (Hironaka, 1998) and AOAC laboratory - Vietnamese standard 6626-2000 (Vilas). Results show that the As concentration ranging from 15 to 1,650 µg/l is found in 520 private tubewells at depth between 15 and 90 m, while being rare or very low at depth between 200 and 300 m. High As content is usually found in 15-70m tubewells in which approximately 70 - 80% of tubewells having arsenic levels of >500 µg/l are located at some areas in Dong Thap and An Giang provinces in the upper MRD plain. Bore core drilling records show a probable relationship between As concentration in groundwater and sedimentary facies in the MRD. The highest As content is found along the Mekong River valleys in the Late Pleistocene and Holocene aquifers. Keywords: Mekong River Delta; Arsenic contamination; Groundwater; Sedimentary facies. ©2016 Vietnam Academy of Science and Technology 1. Introduction The Mekong Delta, one of the largest deltas in Southeast Asia, is located at the mouth of the Mekong River in Southern Vietnam. The river has its headwaters in the Tibetan mountains, drains a catchment area of 800×103 km2, discharge 470 km3 of water and 160 million .

• Địa Lý
• Vietnam Journal of Earth Sciences
• High arsenic concentration in groundwater related to sedimentary facies
• The Mekong River Delta
• High arsenic concentration
• AOAC laboratory Vietnamese standard
• General characteristics of rare earth
• Radioactive elements in Dong Pao deposit
• The natural tap and thermal waters
• Liquid scintillation counter
• Probabilistic seismic hazard assessment for the South Central Vietnam
• Probabilistic seismic hazard assessment
• The South Central Vietnam
• Recent seismotectonic and geodynamic
• Prediction of maximum earthquake magnitude for northern Vietnam region
• The gev distribution
• Maximum earthquake magnitude
• Generalized extreme value distribution
• The earthquake catalog of Northern Vietnam
• Continuous GPS network in Vietnam
• The total electron
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• The continuous GPS network
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• Upper Permian lower Triassic volcanic sequences
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• northwest Vietnam
• Insignificant cumulative displacement
• Oriented core samples
• An analysis of forest biomass changes
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• Central Highlands of Vietnam
• SPOT HRV satellite
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• Construction of initial national quasi geoid model VIGAC2017
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• The relation between fault movement potential
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• Dipterocarpaceae Blume family
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• Cau river basin in Vietnam
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• Thai Binh province
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