Modeling Volatile Organic Compound Transport in Composite Liners

Abstract

Data from bench-scale composite liner experiments were compared with predictions made with two models, a finite-difference model and a semianalytical model, used to predict volatile organic compound (VOC) transport through composite liners. Transport parameters for the geomembrane and clay for five common VOCs were measured independently and used as input. Predictions from both models for all five VOCs were essentially identical. Excellent agreement was obtained between the predicted and measured concentrations for all five VOCs without model calibration. However, inherent variability in measured transport parameters has a significant effect on predictions. Volatile organic compound concentrations in the clay liner near the geomembrane-clay interface depend primarily on transport parameters for the geomembrane. However, this becomes less significant as the distance from the geomembrane-clay interface increases.