About 7:58 a.m., on July 26, 1980, 4 locomotive units and 17 cars, including 7 placarded tank cars containing hazardous materials, of Illinois Central Gulf Railroad Company freight train No. 64 were derailed while moving at a calculated speed of about 35 mph around a 6 curve in Muldraugh, Kentucky. Two tank cars of vinyl chloride were punctured and their contents burned. Flames impinged two other tank cars of vinyl chloride, causing one to vent toxic fumes, but neither car ruptured. About 6,500 persons were evacuated from Muldraugh and the U.S. Army installation at Fort Knox. Four train crewmembers were injured during the derailment, and property damage was estimated at $1,348,394.