Arsenic mobility in contaminated lake sediments

• Published in: Environmental pollution (1987) 2004-06, Vol.129 (3), p.479-487
• Main Authors: Nikolaidis, Nikolaos P., Dobbs, Gregory M., Chen, Jing, Lackovic, Jeffrey A.
• Format: Article
• Language: English
• Subjects: Applied sciences; Arsenic; Arsenic - chemistry; Biological and physicochemical properties of pollutants. Interaction in the soil; Continental surface waters; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Environmental Monitoring - methods; Exact sciences and technology; Fresh Water - chemistry; Geologic Sediments - chemistry; Kinetics; Lake sediments; Landfill; Mobility; Modelling; Models, Chemical; Natural water pollution; Pollution; Pollution, environment geology; Soil and sediments pollution; Water Pollutants, Chemical; Water treatment and pollution
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2003.11.005

An arsenic contaminated lake sediment near a landfill in Maine was used to characterize the geochemistry of arsenic and assess the influence of environmental conditions on its mobility. A kinetic model was developed to simulate the leaching ability of arsenic in lake sediments under different environmental conditions. The HM1D chemical transport model was used to model the column experiments and determine the rates of arsenic mobility from the sediment. Laboratory studies provided the information to construct a conceptual model to demonstrate the mobility of arsenic in the lake sediment. The leaching ability of arsenic in lake sediments greatly depends on the flow conditions of ground water and the geochemistry of the sediments. Large amounts of arsenic were tightly bound to the sediments. The amount of arsenic leaching out of the sediment to the water column was substantially decreased due to iron/arsenic co-precipitation at the water-sediment interface. Overall, it was found that arsenic greatly accumulated at the ground water/lake interface and it formed insoluble precipitates. Arsenic accumulates at the ground water/lake interface, where it forms insoluble precipitates.