GTW GP 38 4920 switching Dunn Paper in Port Huron, Michigan on July 25th, 2013. Seen passing underneath the Blue Water Bridge and along the shore of Lake Huron.
This is a daily train that switches two local paper plants. It is based out of the CN tunnel yard in Port Huron. The time of day varies but is usually late afternoon. Best bet is to go to the Amtrak station and watch the trains go in and out of the tunnel.