EE WAS OPERATING A BULLDOZER STRIPPING IN THE PIT. HE BACKED THE DOZER INTO AN UNSTABLE AREA AND THE RIGHT DOZER TRACK SLID DOWN A SHORT FREEWALL AND TURNED OVER ON IT'S RIGHT SIDE. HE WAS WEA RING HIS SEATBELT AT THE TIME. HE EXITED THE EQUIPMENT AND REPORTED THE ACCIDENT TO HIS SUPERVISOR. HE DID NOT SEEK MEDICAL TREATMENT UNTIL 4/29 FOR POSSIBLE SHOULDER STRAIN.