Surfactant selection criteria for enhanced subsurface remediation: Laboratory and field observations

Abstract

Traditional approaches to ground water remediation have proven ineffective, especially when trapped oil phases exist. Surfactants are being widely evaluated to enhance remediation of such ground water contamination episodes. Successful implementation of surfactant enhanced subsurface remediation requires careful consideration of fundamental surfactant properties. The economic viability of this technology requires targeting the residual contamination, minimizing surfactant losses, and recovery and reuse of the surfactant. The relative efficiencies and advantages of surfactant solubilization and mobilization systems are described, as well as means to optimize these systems. Unit processes for contaminant-surfactant separation and surfactant reuse are summarized, along with unique surfactant impacts on these separation processes. Factors affecting the environmental acceptability of surfactants are discussed. Finally, results of field demonstrations are presented that reinforce concepts presented. This study thus provides an introduction to surfactant chemistry and highlights key factors critical to the successful design and implementation of surfactant enhanced subsurface remediation systems.