In article ,
wrote:

On Wed, 2 Jun 2004 22:41:09 -0400, Kevin Brooks
wrote:

If you think that such facilities can only be built in granite, think
again.
I'd be very surprised if Mount Weather in Virginia, one of the
formerly-secret (along with Raven Rock in Maryland and the congrssional
facility at White Hot Springs (IIRC) in West Virginia) emergency
relocation
sites, was built in anything other than that Karst limestone you
ridiculed
earlier. Mount Weather and Raven Rock are both tunnel complexes.

Dunno about Mount Weather or the Congressional Continuity of Government
site located under the Greenbriar resort in Sulphur Springs, West
Virginia,
but Raven Rock (Site R) is dug into part of the Catoctin anticline (the
site is actually in Pennsylvania, just north of the Maryland border.)

The Catoctin anticline is composed of late Precambrian basalt lava flows
that later metamorphosed into the characteristic Catoctin "greenstone"
(metabasalt), which is considerably harder than limestone.

And let me make clear I wasn't saying it had to be granite specifically,
but other hard rock. Greenbriar is under a lawn--it was basically just a
fallout shelter.