Recent experimenss by Finno et al. (1996) suggest that the evoluteon of localized zones in granular materials can be complex and is strongly influenced by local fluid flow even when condition are globally undrained. A simple model of the drained response in terms of the shear stress and porosity dependence on strain is used to calculate the corresponding undrained response. The calculation suggest that relatively small variations in the porosity response can dramatically affect the mdrained shear stress response. The effect of nonuniformity is examined by including a small layer with slightly different prop erties embedded in an infinite body and assuming that fluid mass exchange is proportional to differences in pore pressure.