Webb's problem is discussed in White Papers Vol.1 and the FEFLOW book. The results are in good agreement with TOUGH2. Also it is mentioned that "there is a good qualitative and quantitative agreement between the analytical and the numerical results". To me it's not clear how to verify these results against analytics. The analytical diversion lenght is 32.6 meters. As it can be seen from the picture, the diversion length calculated by FEFLOW is approximately 45 meters (location of the first point with leakage/infiltration=1). Is it a good or a bad value? What are the principles of comparison of numerical results with analytics for this problem?