Monte Carlo simulations of a model for the stripping of root3xroot3 R30degrees alkanethiol lattices from terraces and steps of a (111) metal face in aqueous solutions are presented. In the model the stripping probability of an adsorbed alkanethiolate molecule depends on the applied potential, on intermolecular forces that stabilize the alkanethiol layer, and on the presence of substrate defects. Stabilizing intermolecular forces are also responsible for alkanethiolate aggregate formation during the stripping process. Snapshots and voltammograms derived from the model reproduce experimental STM images and electrochemical data for alkanethiol stripping from the Au(111) surface.