Discussion of :identification of contaminant source location and release history in aquifers" by Mustafa M. Aral, Jiabao Guan, and Morris L. Maslia

[Extract] The authors have presented an interesting approach for the characterization of unknown contaminant sources in groundwater systems. The solution results obtained for the illustrative source identification problem are no doubt encouraging. The most important aspect of this work is that the authors are able to locate the sources in a continuous scale by defining a potential location region and not discrete locations. This is a noteworthy contribution. This discusser would like to point out a few related issues that the authors could have raised or discussed to better enlighten the readers