According to this post (http://ngdiscussion.net/phorum/read.php?1,374189,374243#msg-374243):
"Also in the immediate future #18 will be pinch hitting for the diesel and be pulling the Rockwood to Cascade Express this coming Thursday the 18th for those in the area. Standard pricing applies so heres a cheap chance to ride #18. "
My guess is that the ticket office hasn't been informed yet.
Greg Coit
Bayfield, CO