INJURED STATED THAT HE WAS LIFTING/LOADING BELT STRUCTURE/STANDS IN THE SCOOP BUCKET WHEN HE FELT A PULL IN HIS LOWER BACK. INJURED WAS TAKEN TOTHE HOSPITAL. INJURED'S EXCUSE SAID HE WAS TO BE OFF UNTIL 4-17-02 & THEN RETURN TO WORK ON LIGHTDUTY FOR A WEEK BUT HE DID NOT RETURN UNTIL 4-23-02. WHEN ASKED WHY HE DID NOT RETURN ON 4-17-02, COMMENT WAS HE DID NOT PAY ATTENTION TO RELEA