A heuristic procedure to optimize the design of a permeable reactive barrier for in situ groundwater remediation

This paper deals with a procedure to optimize the design of permeable reactive barrier (PRB) built with activated carbon for the in situ remediation of a polluted aquifer. A simulation-based heuristic procedure is developed to define, with an iterative procedure, the optimal position and geometrical dimensions of the bather itself, which simultaneously assure the respect of pollutant concentration limits and minimum barrier size. A computer code is used to describe the field motion of the aquifer, the contaminant transport and the adsorption phenomena occurring inside the barrier. A real aquifer polluted by tetrachloroethylene (PCE) situated in the area north of Naples (Italy) is presented as a case study. Simulation results show that a PRB formed by sections of different width, tuned to the different values of PCE concentration in the plume, can assure an effective remediation of the site.