Methods and apparatus are provided for polishing barrier layer materials. In one embodiment, a composition is provided for removing at least a barrier material from a substrate surface, including includes a base composition, a silica abrasive, a solvent, a pH between about 7 and about 10, and one or more components selected from the group of a metal passivating compound, an oxidizer, and an alumina abrasive. The composition may be used to chemical mechanical polishing process a substrate surface having a ruthenium-based barrier and one or more material selected from the group of a polysilicon layer, a dielectric layer, or metal layer.