Hello Rodger

The Fairfax Seminary Hospital was in Alexandria, Virginia.
It is currently called the Virginia Theological Seminary.

See:

http://www.vts.edu

http://www.mikelynaugh.com/VirtualCivilWar/New/Originals2/pages/FairfaxSeminaryAlexandria.html

http://www.edinborough.com/Books/HospitalDays.html