title: Correlation between DNAPL distribution area and dissolved concentration in surfactant enhanced aquifer remediation effluent: A two-dimensional flow cell study.
abstract: During the process of surfactant enhanced aquifer remediation (SEAR), free phase dense non-aqueous phase liquid (DNAPL) may be mobilized and spread. The understanding of the impact of DNAPL spreading on the SEAR remediation is not sufficient with its positive effect infrequently mentioned. To evaluate the correlation between DNAPL spreading and remediation efficiency, a two-dimensional sandbox apparatus was used to simulate the migration and dissolution process of 1,2-DCA (1,2-dichloroethane) DNAPL in SEAR. Distribution area of DNAPL in the sandbox was determined by digital image analysis and correlated with effluent DNAPL concentration. The results showed that the effluent DNAPL concentration has significant positive linear correlation with the DNAPL distribution area, indicating the mobilization of DNAPL could improve remediation efficiency by enlarging total NAPL-water interfacial area for mass transfer. Meanwhile, the vertical migration of 1,2-DCA was limited within the boundary of aquifer in all experiments, implying that by manipulating injection parameters in SEAR, optimal remediation efficiency can be reached while the risk of DNAPL vertical migration is minimized. This study provides a convenient visible and quantitative method for the optimization of parameters for SEAR project, and an approach of rapid predicting the extent of DNAPL contaminant distribution based on the dissolved DNAPL concentration in the extraction well.
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Beijing Municipal Research Institute of Environmental Protection, Beijing 100037, China.
authors.forename: Huiying
authors.initials: H
authors.lastname: Li
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Du
authors.affiliation: Pacific Northwest National Laboratory, Richland, WA 99352, USA.
authors.forename: Lirong
authors.initials: L
authors.lastname: Zhong
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Du
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
authors.forename: Qingbao
authors.initials: Q
authors.lastname: Gu
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China. Electronic address: ligulax@vip.sina.com.
authors.forename: Fasheng
authors.initials: F
authors.lastname: Li
mesh_terms: D052918:Environmental Restoration and Remediation; D005025:Ethylene Dichlorides / Q000032:analysis*; D060587:Groundwater / Q000032:analysis*; D008962:Models, Theoretical; D013501:Surface-Active Agents / Q000032:analysis*; D014872:Water Movements; D014877:Water Pollution, Chemical / Q000517:prevention & control*
chemical_list: D005025:Ethylene Dichlorides; D013501:Surface-Active Agents; C024565:ethylene dichloride
keywords: DNAPL; Dissolved concentration; Distribution area; Mass transfer; Surfactant