Groundwater Contamination Due to Arsenic, Iron, Ammonia, and Organic Matter in Hanoi City, Vietnam
Year: 2003
Type: article
Abstract: The investigations on ground water contamination in Hanoi City, Vietnam were carried out in August and December 2000.Most of the water samples were taken from the deep wells that tap the lower aquifer.High concentration of arsenic (up to 110 f.tgll), iron ( up to 32 mgll), ammonia (up to 29 mgll) and DOC (up to 9 mgll) were detected in the groundwater in the South of Hanoi, however, a lower concentration range of those species were found on the North part.The results showed very good correlation among different water quality parameters, such as DOC vs TN, NH4-N vs HC0 3 ', As vs Fe(II), NH4-N vs Fe(II), and As vs HC0 3 • From these data combined with the hydro-geological profiles, a possible mechanism of simultaneous ground water pollution by As, Fe(II), ~-N and organic matter was discussed.Under anaerobic condition, there is a combination of the microbial oxidation of organic matter and reduction of Fe(III) to Fe(II).High As concentration in the deep groundwater may be derived from reductive dissolution of As-rich Fe oxyhydroxide minerals, and reduced by either microbial activities or chemical reaction, or both.
Authors: Satoshi Takizawa, Thi Viet Nga Tran, Masafumi Inoue, Nawa Raj Khatiwada, Van Ngoi Chu, Trong Nhuan
Language: English
Subfield: Environmental Chemistry
Field: Environmental Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2575255699