On July 31, 1979, at 10:30 p.m., eastbound Union Pacific (UPRR) freight train No. GRX 31 derailed at Granite, Wyoming. The train was moving on main track No. 2 at 75 mph when the second and third locomotive units derailed and overturned in a 305.8' curve, separated from the lead unit, destroyed the track, and caused the following 81 freight cars to derail. Two locomotive units were heavily damaged, 80 freight cars were destroyed and 2 overpass bridges of Interstate 80 were damaged extensively. Total damage was estimated at $5 million.