SVE works by moving vapor through the soil column and collecting volatile contaminants in the vapor stream as it passes through. SVE also adds oxygen to the system, which can enhance biodegradation of amenable compounds.
For most in the industry, SVE has been designed using a field parameter called the radius of influence. ROI is a real measurement, but by itself has very little to do with the effectiveness of SVE or lack thereof. Flow rates and paths relative to the target contamination are the key attributes to successful SVE design.
An efficient SVE design will collect more contaminant mass in less time and at less cost than a system designed by ROI methods. Both well-designed and poorly designed systems go asymptotic, but the well-designed system leaves much less residual contamination and therefore greatly reduces the risk and potential liability. Poorly designed systems often leave zones of original contamination untouched, and therefore provide no real value because the risk & liability are unchanged.
Contact AVI for more details and examples of our applied approaches for designing & optimizing SVE systems, as well as defining endpoints of cleanup.