paraphase text; However, to consider an alternative performance of the GCL system it must be greater than that of the CCL system. GCL's do have advantages over CCLs in that they are easily and install, with straightforward (common sense procedures), GCLs will not dissociate in the construction phase (unless prematurely hydrated) CCls can desiccate early in construction, and the GCL materials are easy to acquire. However, the performance of the GCL must match the 95% relative compaction of the CCL with a hydraulic conductivity of 3x10^-10 cm/sec