Abstract: ON MARCH 25, 1993, EMPLOYEE #1, A WATER TREATMENT OPERATOR, WAS ASKED TO DRAIN A 12,000 GALLON TANK THAT CONTAINED CAUSTIC SODA (7% BY WEIGHT OF SODIUM HYDROXIDE, ACCORDING TO THE EMPLOYER). THE AMOUNT OF SODIUM HYDROXIDE IN THE TANK AT THE TIME OF THE ACCIDENT WAS UNKNOWN. THE ONLY PROTECTIVE CLOTHING EMPLOYEE #1 DONNED WAS PROTECTIVE GOGGLES. HE THEN REMOVED THE TANK'S PLUG, WHICH WAS LOCATED AT THE BOTTOM OF THE TANK, WITH A CRESCENT WRENCH. THE CAUSTIC SODA GUSHED OUT OF THE OPENING AND SPLASHED EMPLOYEE #1 IN HIS FACE AND SEEPED INTO THE SIDE VENTS OF HIS GOGGLES, BURNING HIS EYES. THE TANK WAS LOCATED IN AN 11-FOOT CEMENT TRENCH, SO EMPLOYEE #1 HAD TO RADIO FOR ASSISTANCE TO GET OUT OF THE TRENCH AND TO A NEARBY (15 TO 25 FEET AWAY) EYE/FACE WASH STATION. EMPLOYEE #1 WAS TAKEN TO SAN ANTONIO HOSPITAL WHERE HE WAS DIAGNOSED AS HAVING A CORNEAL BURN. AT THE TIME OF THIS INSPECTION, THE EMPLOYEE HAD NOT FULLY RECOVERED HIS VISION.