Just to clarify things a little: the steel part of the bridge was built to accommodate two tracks, which was common practice at the time, but the second track was never built, except for the M/W set-out track. There once was a siding on the Tracy line from Newark westward, but this ended right about the chemical plant. The last time I ran a train across it (c1980), great sheets of rusty metal and paint would come raining down.