title: In situ construction of low permeable barrier in soil to prevent pollutant migration by applying weak electric field.
abstract: In order to prevent vertical migration of pollutant in soil matrix, this study firstly proposed to construct an in situ low permeable barrier (LPB) through synchronously transporting calcium and carbonate. After LPB construction, the soil permeability was declined tenfold. Exchangeable calcium (37.3%) and calcium bonding to carbonate (41.7%) respectively alleviated flocculation of microaggregates and cementation of marcoaggregates. Accordingly, smaller particles (<1 mm) aggregated into bigger ones (>2 mm) after electrokinetic remediation. The other soil characters like pH, moisture, and bacterial communities were well preserved after remediation. In addition, the pollutant prevention was divided into two phases as unsaturated phase and saturated phase. In unsaturated phase, phenol, F-, Cd2+, and Ni2+in filtrate were all lower than 0.1 mg, and Cr2O42--Cr discharged from LPB was 1/5.1 than that from initial soil. In saturated phase, LPB prevented 4.3-12.1 fold pollutant than initial soil. Taken together, proposed method could effectively prevent vertical migration of pollutants, indicating significant values for saving soil remediation cost or avoiding contamination of underground water.
authors.affiliation: Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China.
authors.forename: Si
authors.initials: S
authors.lastname: Chen
authors.affiliation: Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China. Electronic address: liuxiang@fudan.edu.cn.
authors.forename: Xiang
authors.initials: X
authors.lastname: Liu
authors.affiliation: Center of Analysis and Measurement, Fudan University, Shanghai 200433, China.
authors.forename: Li
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China. Electronic address: hitwan@163.com.
authors.forename: Chunli
authors.initials: C
authors.lastname: Wan
mesh_terms: D004560:Electricity; D052918:Environmental Restoration and Remediation; D010636:Phenols; D012987:Soil; D012989:Soil Pollutants
chemical_list: D010636:Phenols; D012987:Soil; D012989:Soil Pollutants
keywords: Actual soil; Calcium; Electric field; Low permeable barrier; Pollutant migration