Abstract: ON MAY 30, 1985, AT ABOUT 12:45 PM EMPLOYEE #1 RETURNED TO THE SHOP YARD WITH A TANKER TRUCK WHICH WAS USED FOR HAULING OIL FIELD WASTE WATER AND FRESH WATER. UPON RETURNING TO THE SHOP YARD, EMPLOYEE #1 TOLD A FELLOW EMPLOYEE THAT THERE WAS A HEAVY VIBRATION IN THE DRIVE TRAIN OF THE TRUCK AND THAT THE FLOAT GAUGE FOR THE TANK WAS NOT WORKING. THE OTHER EMPLOYEE CHECKED THE AUXILIARY TRANSMISSION AND FOUND SOME LOOSE BOLTS. HE ALSO TOLD EMPLOYEE #1 THAT HE WAS NOT GOING TO WORK ON THE FLOAT GAUGE BECAUSE THERE WAS A SMELL OF HYDROGEN SULPHIDE GAS, EVEN THOUGH THE TANK WAS CLOSED. THE OTHER EMPLOYEE GATHERED UP SOME TOOLS AND WENT UNDER THE TRUCK. EMPLOYEE #1 WAS LAST SEEN IN THE SHOP. WHILE THE OTHER EMPLOYEE WAS UNDER THE TRUCK, HE HEARD THE TOP HATCH OF THE TANK OPEN AND THEN HE HEARD EMPLOYEE #1'S BODY HIT THE BOTTOM OF THE TANK. THE OTHER EMPLOYEE CAME OUT FROM UNDER THE TRUCK AND SAW THAT EMPLOYEE #1 WAS LYING ON HIS BACK INSIDE THE TANK. AT ABOUT 1:10 PM, THE OTHER EMPLOYEE CALLED EMERGENCY. HE THEN OPENED THE DUMP VALVE ON THE TANK, STARTED THE TRUCK, AND PUT THE VACUUM PUMP INTO GEAR TO HELP CLEAR THE TOXIC GASES FROM INSIDE THE TANK. THE OTHER EMPLOYEE THEN TOOK AN AIR LINE FROM INSIDE THE SHOP AND WAS IN THE PROCESS OF BLOWING FRESH AIR INTO THE TANK WHEN THE EMERGENCY UNITS ARRIVED AT APPROXIMATELY 1:20 PM. EMPLOYEE #1 WAS REMOVED FROM THE TANK AT APPROXIMATELY 1:30 PM. MEDICAL PERSONNEL WERE UNABLE TO REVIVE HIM.