摘要
The Yongding River in the western suburbs of Beijing has been recharged with reclaimed water since 2010 for the purpose of ecological restoration.Where the reclaimed water is not well treated,it poses a danger to the aquifer underneath the river.To provide a reliable tool which could be used in future research to quantify the influence of reclaimed water in the Yongding River on the local groundwater environment,a transient groundwater flow and reactive solute transport model was developed using FEFLOW^TM in the middle-upper part of the Yongding River Alluvium Fan.The numerical model was calibrated against the observed groundwater levels and the concentrations of typical solutes from June 2009 to May 2010 and validated from June 2010 to December 2010.The average RMSE and R2 of groundwater level at four observation wells are 0.48 m and 0.61,respectively.The reasonable agreement between observed and simulated results demonstrates that the developed model is reliable and capable of predicting the behavior of groundwater flow and typical contaminant transport with reactions.Water budget analysis indicates that the water storage in this aquifer had decreased by 43.76×10^6m^3 distributions of typical solutes suggest that the middle and southern parts of the unconfined aquifer have been polluted by previous discharge of industrial and domestic sewage.The results underscore the necessity of predicting the groundwater response to reclaimed water being discharged into the Yongding River.The study established a coupled groundwater flow and reactive solute transport model in the middle-upper part of the Yongding River Alluvium Fan,one of the drinking water supply sites in Beijing city.The model would be used for risk assessment when reclaimed water was recharged into Yongding River.
基金
the project of the National Natural Science Foundation of China (Grant Nos.51379207 and 51609118)
Beijing Municipal Science and Technology Project (No.D090409004009004).
