Leakage through Flaws in Geomembrane Liners

Leakage through flaws in geomembranes was examined with laboratory experiments and modeling. Mathematical models were developed using analytical and numerical solutions to calculate leakage through flaws. The models were verified with laboratory experiments. The system geometry around a flaw was found to control leakage. Comparison of theoretical and experimental leakage rates indicated that under effective stress gaps close and flaws become infilled resulting in a decrease in leakage. Infilling of flaws becomes important in controlling flow when the membrane is thick relative to the size of the flaw. Simple leakage equations are presented that can be used to quantify the leakage rate from composite liners. For flaws that are small relative to the clay layer thickness, leakage is independent of the thickness of the clay layer in a composite liner.