Persistent Source Influences on the Trailing Edge of a Groundwater Plume, and Natural Attenuation Timeframes: The F-Area Savannah River Site
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- 作者：Jiamin Wan ; Tetsu K. Tokunaga ; Wenming Dong ; Miles E. Denham ; Susan S. Hubbard
- 刊名：Environmental Science & Technology (ES&T)
- 出版年：2012
- 出版时间：April 17, 2012
- 年：2012
- 卷：46
- 期：8
- 页码：4490-4497
- 全文大小：493K
- 年卷期：v.46,no.8(April 17, 2012)
- ISSN：1520-5851
文摘
At the Savannah River Site鈥檚 F-Area, wastewaters containing radionuclides were disposed into seepage basins for decades. After closure and capping in 1991, the U.S. Department of Energy (DOE) has being monitoring and remediating the groundwater plume. Despite numerous studies of the plume, its persistence for over 20 years has not been well understood. To better understand the plume dynamics, a limited number of deep boreholes were drilled to determine the current plume characteristics. A mixing model was developed to predict plume tritium and nitrate concentrations. We found that the plume trailing edges have emerged for some contaminants, and that contaminant recharge from the basin鈥檚 vadose zone is still important. The model鈥檚 estimated time-dependent basin drainage rates combined with dilution from natural recharge successfully predicted plume tritium and nitrate concentrations. This new understanding of source zone influences can help guide science-based remediation, and improve predictions of the natural attenuation timeframes.