Advantages to the technology include its potential applicability to a broad range of contaminants and acceleration of site clean up relative to conventional pump and treat. Limitations include the potential for spreading the contaminants unless implementation is tightly controlled and consequent limited regulatory acceptance, site geologic setting limitations, and uncertainties involved in prediction of performance and clean up duration.
In Situ Flushing - Technology Overview
In situ flushing is the injection or infiltration of an aqueous solution into a zone of contaminated soil/groundwater, followed by downgradient extraction of groundwater and elutriate (flushing solution mixed with the contaminants) and aboveground treatment and discharge or re-injection. Flushing solutions range from plain water to surfactants, cosolvents, or other facilitators. In situ flushing enhances conventional pump and treat technology through increasing the efficiency of a flushing pore volume, or accelerating natural flushing action. Successful application of the technology is highly site-specific, though it is not limited by the depth of the contaminant or their location within the hydrogeologic regime. The site specificity of application of this technology necessitates extensive pre-design data collection and treatability studies.