A chemical mechanical polishing system having a dual position slurry/rinse arm for moving between a polishing position in which slurry is supplied to a polishing pad from a location remote from the polishing pad's center, and a rinsing position in which rinsing fluid is supplied from a location above or adjacent the polishing pad's center. The rinsing fluid is preferably sprayed from one or more nozzles that extend from the edge of the polishing pad to the center of the polishing pad. Preferably, in the polishing position, the slurry/rinse arm is positioned horizontally remote from the polishing pad's center and supplies slurry to the polishing pad via a horizontally angled slurry supply line. The slurry/rinse arm may include a gimbled brush for contacting the polishing pad when the slurry/rinse arm is in the rinsing position, and may further include brush nozzles positioned to direct rinsing fluid to the brush so as to rinse particles therefrom. Rinsing fluid nozzles may also be angled to spray rinsing fluid in front of the brush, so as to prewet the polishing pad.