Publication: Mechanisms of arsenic contamination associated with hydrochemical characteristics in coastal alluvial aquifers using multivariate statistical technique and hydrogeochemical modeling: a case study in Rayong province, eastern Thailand
Issued Date
2020-01-01
Resource Type
ISSN
15732983
02694042
02694042
Other identifier(s)
2-s2.0-85092504220
Rights
Mahidol University
Rights Holder(s)
SCOPUS
Bibliographic Citation
Environmental Geochemistry and Health. (2020)
Suggested Citation
Satika Boonkaewwan, Prinpida Sonthiphand, Srilert Chotpantarat Mechanisms of arsenic contamination associated with hydrochemical characteristics in coastal alluvial aquifers using multivariate statistical technique and hydrogeochemical modeling: a case study in Rayong province, eastern Thailand. Environmental Geochemistry and Health. (2020). doi:10.1007/s10653-020-00728-7 Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/59959
Research Projects
Organizational Units
Authors
Journal Issue
Thesis
Title
Mechanisms of arsenic contamination associated with hydrochemical characteristics in coastal alluvial aquifers using multivariate statistical technique and hydrogeochemical modeling: a case study in Rayong province, eastern Thailand
Other Contributor(s)
Abstract
© 2020, Springer Nature B.V. Abstract: The rapid development of Rayong Province has resulted in increased demands on groundwater usage. This has potentially induced the release of contaminants such as arsenic (As), among others (i.e., NO3−, PO43−) from various land use types—especially in intensive agricultural areas and heavy industrial areas, including landfill sites. The objectives of this research are to investigate the As speciation and groundwater chemistry occurring due to different hydrogeological settings and the influence of human activities and to explain the mechanism of As release in the coastal alluvial aquifers in Rayong Province using multivariate statistical techniques and hydrogeochemical modeling (PHREEQC). Six major water facies, mainly consisting of Ca–Na–HCO3–Cl and Ca–Na–Cl, were included in the hydrochemical analysis. Arsenic levels were inversely correlated with NO3−, SO42−, DO, and ORP, confirming the reducing environment in the groundwater system. The results from the PHREEQC model show that most wells were strongly under-supersaturated with respect to arsenorite, scorodite, and arsenic pentoxide. Arsenic (As) is probably derived from the dissolution of Fe oxide and hydroxide (i.e., Fe(OH)3, goethite, maghemite, and magnetite). The multivariate statistical techniques revealed that the As species mainly consisted of As(III), governed by the reducing environment, while As(V) may be desorbed from Fe oxide and hydroxide as the pH increases. Anthropogenic inputs and intensive pumping may enhance the reducing environment, facilitating the release of As(III) into the groundwater. The knowledge gained from this study helps to better understand the mechanisms of As contamination in coastal groundwater aquifers, which is useful for groundwater management, including the optimum pumping rate and long-term monitoring of groundwater quality. Graphic abstract: [Figure not available: see fulltext.]