Ballast Regulator, Old

This old ballast regulator, devoid of any nameplates or other information (except that its motor was made by Detroit Diesel), sits just east of the former Greenbrier (sic) Dock near Vansant in Buchanan County VA. The Greenbrier facility closed in 2006. I have been unsuccessful in finding out when it was constructed. In early 2000’s, Greenbrier Dock was loading coal from the Lovers Gap mine, just a few miles away.