THE EMPLOYEE WAS OPERATING A DOZER. HE WAS LOOKING BACK OVER HIS SHOULDER WATCHING THE ""RIPPERS""ON THE DOZER AND HIT A ROCK. HE TWISTED HIS LOWER BACK, NECK AND LEFT SHOULDER. HE WAS SEEN IN E .R. AND RECEIVED A FULL DUTY RELEASE. ON 6-21-01 HE CONTINUED TO HAVE PROBLEMS AND WAS PLACED ON RESTRICTED DUTY. HE RETURNED TO WORK FULL DUTY ON 7-3-01.