Conrail acquired the11 "Super 7" B23-7R locomotives with the coal hauling Monongahela Railway in 1992. The locomotives were rebuilt for the Monongahela by General Electric from Western Pacific U23-B's in 1989. These unique locomotive have modern dash 8 style carbodies. However, they still ride on the EMD Blomberg trucks from retired F-Units they were initially delivered with to the Western Pacific as U23B's in 1972.
These powerful low speed haulers tend to stay on their native territory dragging coal out of the narrow valleys of southwestern Pennsylvania and West Virginia .