Addy:
1100 Alabama Avenue SE
Washington, D.C.
Construction/Renovation has started for the new Homeland Security operations. Supposedly the directory of homeland security will have the office in the admin section of the kirkbride.
It is currently accessible with GSA permission only, and is heavily guarded, as well as many construction workers all over. The kirkbride still has yet to fall into renovation, and is wide open, but access inside is not allowed.
More info:
http://en.wikipedia.org/wiki/St._Elizabeths_Hospital