WORKER WAS DRIVING WATER TRUCK DOWN A NEWLY CONSTRUCTED ROAD FROM 5TH TO 4TH BENCH AT QUARRY. TRUCK SLID TOWARD EDGE OF ROAD. WORKER KEPT DRIVING TO TRY TO CORRECT SLIDE BUT WAS UNABLE TO. TRU CK ROLLED OVER EDGE OF ROAD AND SLID DOWN TO NEXT BENCH. WORKER INJURED RIGHT ARM WHEN TRUCK ROLLED OVER.