Modeling And Remedying Petroleum Contaminant In Groundwater Systems Under Uncertainty

Uncertainties have been found to widely exist in contaminant fate and transport in groundwater systems. Therefore, this study aims to propose a modified fractional fuzzy simulation (MFFS) method to predict the uncertainty in toluene and oxygen concentrations in groundwater systems under microbial attenuation conditions. The method integrates contaminant fate and transport models and fuzzy parameters analysis within a general framework. Compared to the conventional fractional fuzzy simulation (FFS), fewer interior points of fuzzy parameters can be used, thus reducing the simulation time. The method is applied to an aquifer of the Pinggu site in Beijing, China, where three parameters (longitudinal dispersivity, hydraulic conductivity and storage coefficient) are represented as fuzzy sets. According to the spatial-temporal distributions of toluene and oxygen concentrations, this study proposes two remediation systems: pump and treat (P&T) and in-situ bioremediation. In terms the MFFS results, both the two remediation systems demonstrate a good effect on toluene removal. It is thus indicated that the method is useful for not only groundwater simulation, but also risk assessment, remediation design and process control under complex parameter uncertainty.