I found this buried in the Guardian. I had never heard of it...but I guess it sounds plausible.
http://www.guardian.co.uk/usa/story/0,,1859815,00.html>>>>snip
Mount Weather is a top-security underground installation an hour's drive from Washington DC. It has its own leaders, police, fire department - and laws. A cold war relic, it has been given a new lease of life since 9/11. And no one who's been inside has ever talked. Tom Vanderbilt reports
>>>snip
We are sitting, hazards blinking, in Brown's BMW on a rural road in Virginia's Facquier County, a horsey enclave an hour west of Washington DC. The object of our attention is Mount Weather, officially the Emergency Operations Centre of the Federal Emergency Management Authority (Fema); and, less officially, a massive underground complex originally built to house governmental officials in the event of a full-scale nuclear exchange. Today, as the Bush administration wages its war on terror, Mount Weather is believed to house a "shadow government" made up of senior Washington officials on temporary assignment.
>>>>snip
Residents on the mountain did not need to read the newspapers to discern that something was going on there. Joe Davitt, a retired civil servant who lives in a small A-frame house a mile or so away, told me that on September 11 2001 his wife was returning home from Florida. At the bottom of the hill, he says, she was stopped by state troopers, who asked for identification. At the facility itself, he says, "The Mount Weather guards were not only armed, they had their guns in firing position." John Staelin, a member of the Clarke County Board of Supervisors, says that on September 11, the county's 911 line received a call from an agitated local woman. "She said, 'I wouldn't have believed it if I hadn't seen it with my own eyes, but the whole mountain opened up and Air Force One flew in and it closed right up. I wouldn't have believed it if I hadn't seen it with my own eyes.' So they said, 'Yes, ma'am.' "