The identification of release mechanism of arsenic may assist in designing safe and effective remediation strategies, due to its severe toxicity effect for the human body. In this regards, investigations were carried out to observe the release of As from soil into water. It was found that As concentration increased with decreasing oxidation reduction potential. Arsenic concentrations demonstrated negative covariation with the concentrations of NO3 but strongly correlated with DOC and Fe concentrations. Batch leaching tests at different pH conditions showed a strong pH dependence on arsenic and iron leaching. A numerical simulation of arsenic transport model, coupled with microbially mediated biogeochemical processes was developed for describing the release of As in soil under reducing environment. The simulation concentrations of Mn, Fe and As were well matched those found experimentally. The results of this study suggested that the microbially mediated degradation of organic matter and reductive dissolution of Fe-oxyhydroxide are considered to be the dominant processes to release As in aquifers.
Halim, Md. Abdul; Jinno, Kenji; Razzak, Abdur; Oda, Keita; and Hiroshiro, Yoshinari
"Experimental and Biogeochemcial Modeling Studies on Arsenic Release in Soil Under Anaerobic Condition,"
International Journal of Soil, Sediment and Water:
2, Article 3.
Available at: http://scholarworks.umass.edu/intljssw/vol1/iss2/3