Abstract: Employees #1 through #9 were performing repairs on a pump in the vicinity of a 90 ft high by 16 ft in diameter above-ground atmospheric tank that contained approximately 450 tons of wood pulp and water. The tank, which was constructed of mild steel plate, ruptured, and the employees were enveloped and suffocated. They underwent physical trauma from being violently forced into stationary objects in the work area. Employee #1 was killed and Employees #2 through #5 were hospitalized. The cause of the failure (rupture) was a reduction in the wall plate thickness of the tank as a result of long term corrosion on its exterior.