In the Archives we have a map printed by the Southern of active coal loadouts in October 1984.  Of course it includes the Southern and Interstate lines in southwest Virginia.  I took quick pics of the map last year at a work session to share with a friend who models the ex-Interstate lines in the NS era.  

I don't know if the archives have any earlier versions of that map, or if such exist.

I haven't uploaded anything to Groups.io file section, so I'll try to figure that out tonight.