Publication Details |
| Category | Text Publication |
| Reference Category | Journals |
| DOI | 10.1016/j.scitotenv.2020.144670 |
| Title (Primary) | Utilization of pit Lake on the cleaning process of residual saltwater in unconfined coastal aquifers |
| Author | Zhang, B.; Zheng, T.; Zheng, X.; Walther, M. |
| Source Titel | Science of the Total Environment |
| Year | 2021 |
| Department | ENVINF |
| Volume | 770 |
| Page From | art. 144670 |
| Language | englisch |
| Topic | T5 Future Landscapes |
| Keywords | Seawater intrusion; Numerical models; Subsurface dam; Unconfined coastal aquifers; Pit lake |
| Abstract | Subsurface dams are widely used to prevent saltwater intrusion. Once a subsurface dam is established, a large amount of residual saltwater (RSW) may trap behind the dam and negatively affect the groundwater exploitation over the long term. Based on monitoring hydrological information and field-scale numerical models, we proposed three kinds of RSW clean-up strategy coupling the applications of a pit lake and wells in a coastal aquifer. We firstly investigated the spontaneous natural removal of RSW in an actual coastal aquifer affected by a pit lake, assessed the impact of pit lake drainage on the removal of RSW, and designed a feasible strategy for reducing residual saltwater utilizing both pit lake and wells. Our results indicated that RSW remediation is a slow process under natural conditions. The area of the RSW decreased from 15.17 to 11.62 km2 after 20 years, and the Cl− concentration of RSW around the pit lake increased to 1750 mg/L. The RSW cleaning efficiency can be significantly enhanced by the pit lake drainage process. With the pit lake drainage rate of 1.6E5 m3/d, the area of the RSW decreased by 10.14 km2 in five years being 17-times larger than that of the natural restoration scheme (0.58 km2). With the combined well-lake drainage system, the total residual saltwater area decreased by more than 90% within five years, and the Cl− concentration of RSW almost reached WHO standards for drinking-water quality (250 mg/L). RSW upstream the subsurface dam was thoroughly cleaned up adopting the well–lake drainage strategy. Therefore, a well–lake drainage strategy can be strongly recommended for removing the RSW in coastal aquifers. |
| Zhang, B., Zheng, T., Zheng, X., Walther, M. (2021): Utilization of pit Lake on the cleaning process of residual saltwater in unconfined coastal aquifers Sci. Total Environ. 770 , art. 144670 10.1016/j.scitotenv.2020.144670 |
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