TEA, Inc. recently implemented a large-scale Engineered_PhytoremediationSM system at an active industrial site. Phytoremediation was selected as the preferred remedial strategy to prevent migration of elevated mercury concentrations in groundwater into a nearby water body. The objective of the Engineered_PhytoremediationSM system is to influence the existing hydraulic gradient of shallow groundwater using evapotranspiration by selected plant species in order to maintain potentiometric flow toward the south, away from the adjacent water body. The area of concern is a former landfill that was previously capped to eliminate contaminant exposure from soils beneath the cap, and to control rainwater recharge and surface run-off. The Engineered_PhytoremediationSM system consists of 271 TreeWell® units installed directly through the cap over a one acre area. By using the TreeWell® system, the designers minimized the impact to the landfill’s protective cap while eliminating the possibility of rainwater percolation. Two different plant species (Salt Bush and Afghan Pine) were selected for use in the system based upon results of a phytoremediation pilot study performed at the site. Eleven new monitoring wells were installed which, in addition to seven existing monitoring wells, will provide the necessary monitoring well network to evaluate the hydraulic influence the Engineered_PhytoremediationSM system will have on the site groundwater gradient. Much of the installation was performed at night due to the extreme heat during the summer months.
For more information on TEA’s Engineered_PhytoremediationSM program, please contact Ron Gestler at firstname.lastname@example.org or 925-207-9452.