Abstract: On April 6, 2001, the owner of West Texas Roustabout Company, and two other workers, was working on top of a condensate water tank of a three-tank battery. The owner and another employee were on top of the tank attempting to remove pipe "nipples" from the tank with a 36-inch pipe wrench and "cheater bar". Employee #2 (welder) was on a catwalk adjacent to the top of the tank using a heating torch to heat the "nipple" in an attempt to aid in the removal of the nipple. The attempt to remove the nipple was unsuccessful and the welder was sent down to the company truck to get another wrench and a hammer. As Employee #2 reached the truck, he heard and felt an explosion. Employee #2 turned around to see the tank fully engulfed in flames and the owner and Employee #3 lying on the ground. Earlier in the day a well test had been conducted and product (oil, condensate and natural gas had been pumped into the tank for approximately 30 minutes. After the test, valves in the line from the wellhead to the tank were left in the open position, which allowed product to continue to flow into the tank. The three employees had not been informed that a test had been accomplished or that product had been pumped into the tank.