The Impact of Injection/Pumping Wells on the Pollution Transport in Groundwater

Abstract

The natural quality of groundwater tends to be degraded by industry, agriculture, and wastewater. There are several alternatives to prevent migration and the spread of pollution in groundwater. Some alternatives are physical such as grouting, or slurry walls. Others could be hydrodynamic containment by injection or pumping wells. Injection wells are used to confine a pollutant in place or dilute its concentration by injecting clean water into the aquifer. Pumping wells are used to discharge the pollutants out of the groundwater reservoir or act as interceptors. In this research, the hydraulic characteristics and behavior of the hydrodynamic methods are investigated by using numerical simulation. In this investigation, the numerical model MT3D has been integrally used with the flow model MODFLOW. Injection/pumping rate, screen length and layer, and the number of wells are considered. The results have shown that increasing the rate or the number of injection/pumping wells permits less pollution spread. Changing the screen length of the injection/pumping wells is not effective in preventing pollution from spreading in the long term. Changing the number of wells has more effect on a containment spread. Injection wells can prevent the spread of contaminants more than pumping wells.