It has not been a good year for things falling off mountains in Missoula. A boulder about three feet wide rolled off Mount Sentinel Sunday night onto the University of Montana campus, prompting officials to close a section of Campus Drive. The boulder took out part of a retaining wall before coming to rest on the street near the parking garage on the east side of campus. No one was injured. UM Campus Police say the rock fall evidently was caused by ground saturation and continuing precipitation. The boulder was discover by workers around 6:00 a.m. Monday. UM students were advised not to park on the mountain side of Campus Drive. The M Trail and about 300 yards of Campus Drive will remain closed until conditions stabilize. If you have questions or concerns you can contact Marty Ludeman, UM Office of Public Safety, 243-2277.  DB