Optimization of permeable reactive barrier dimensions and location in groundwater remediation contaminated by landfill pollution

• Published in: Journal of water process engineering 2020-06, Vol.35, p.101196, Article 101196
• Main Authors: Rad, Peyman Rahimi, Fazlali, Ali
• Format: Article
• Language: English
• Subjects: Genetic algorithm; Groundwater treatment; Optimization; Permeable reactive barrier; Simulation
• ISSN: 2214-7144; 2214-7144
• DOI: 10.1016/j.jwpe.2020.101196

•MODFLOW and MT3DMS models are used to simulate groundwater flow and contaminant transport respectively.•The GA is used to find the most economical solution of the problem in the MATLAB environment.•Groundwater flow is assumed to be constant and continuous, and the head of the aquifer is also assumed to be constant.•Dimensional PRB analysis shows the significant effect of width on the reduction of contamination.•The results show the 45% benefit by using PRB comparing to non-using condition. One of the well-known methods is the use of permeable reactive barrier (PRB) to treat groundwater. In order to simulate the PRB design due to the complexity of the equations governing hydraulic flow and pollutant transfer and the integration of these two sets of equations, there is need to use simulated flow and pollutant transfer models. MODFLOW as quantitative model for groundwater flow modeling and MT3DMS qualitative model for groundwater contamination modeling as well as GMS software as graphical interface were used. In the optimization section, due to the extent of decision space in the objective function and the need for high reliability of the selective optimization algorithm, metaheuristic algorithm (GA) is used. The model is implemented under the non-barrier condition and then comparing it with the optimum PRB condition indicates that cost of treatment and total costs are reduced despite consideration costs of manufacturing and active materials presented in PRB and then effect of changes in landfill pollution concentration level was studied in different scenarios. Also, the simulation model was used to investigate the effect of changes of PRB’s active material, length, width and height parameters on pollutant concentration and treatment cost. Of the total PRB costs, 37 % is related to manufacturing costs and 63 % to active materials used in PRB. A comparison of the total costs reveals 45 % benefit in the using condition and the optimum barrier width is 3 m, its length is 35 m and its height is 25 m, located 21 m from the well.