A Three-Dimensional Flow and Transport Modeling of an Aquifer Contaminated by Perchloroethylene Subject to Multi-PRB Remediation

• Published in: Transport in porous media Vol. 91; no. 1; pp. 319 - 337
• Main Authors: Xu, Zengguang, Wu, Yanqing, Yu, Fei
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.01.2012; Springer; Springer Nature B.V
• Subjects: Aquifers; Civil Engineering; Classical and Continuum Physics; Computer simulation; Contamination; Daughters; Dechlorination; Degradation; Earth and Environmental Science; Earth Sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Ethane; Exact sciences and technology; Genetic algorithms; Geotechnical Engineering & Applied Earth Sciences; Groundwater; Hydrogeology; Hydrology. Hydrogeology; Hydrology/Water Resources; Industrial Chemistry/Chemical Engineering; Laboratory tests; Microorganisms; Organic chemicals; Organic chemistry; Parameter estimation; Pollution, environment geology; Remediation; Sensitivity analysis; Tetrachloroethylene; Three dimensional flow; Three dimensional models; Transport; Model; Multi-permeable reactive barriers; MT3DMS; Perchloroethylene; MODFLOW; algorithms; sensitivity analysis; permeability; ground water; degradation; pollution; ethylene; remediation; aquifers; models; adsorption; trichloroethylene; transport; tetrachloroethylene; in situ; contamination; ethane; three-dimensional models; kinetics; porous media
• ISSN: 0169-3913; 1573-1634
• DOI: 10.1007/s11242-011-9847-1

Although subsurface contamination by organic chemicals is a pervasive environmental problem, a permeable reactive barrier (PRB) as a typical in-situ remediation technology is often successful at many sites. Laboratory tests have shown that perchloroethylene (PCE) can be dechlorinated by the combination of zero-valent iron and anaerobic microbial communities (FeMB), and the degradation pathway was: PCE → TCE → 1, 1-DCE → ethylene→  ethane (Ma amd Wu Environ Geol 55(1):47–54, 2008 ). Based on Ma’s experimental results, we have extended MT3DMS to simulate mother-daughter chain reactions using MODFLOW-2005 V1.7/MT3DMS V5.2. Second, using FeMB as multi-PRB’s reactive media, a 5-component transport model for a three-dimensional aquifer contaminated by PCE subject to multi-PRB remediation was built. Third, the adsorption and degradation parameters of reactive media were estimated by means of genetic algorithm. Finally, the three-dimensional, homogeneous aquifer contaminated by PCE subject to multi-PRB remediation was simulated. Overall, the purpose of this paper was to use FeMB as multi-PRB’s reactive media, and develop a modified MODFLOW/MT3DMS that can simulate a three-dimensional aquifer contaminated by PCE and its daughters. Results demonstrated that FeMB could be a potential reactive media for PCE-contaminated groundwater. Multi-PRB could be a preferred option for secondly pollution caused by application of one-stage PRB. The modified MODFLOW/MT3DMS can effectively simulate multispecies mother–daughter chain kinetic reactions. Sensitivity analysis showed that losses of reactivity and permeability may have a significant effect on remediation’s success.