The Chatham facility has provoked much local folklore.  Some clippings from the local newspaper include:

 : Off Mt. Gilead Church Road there is a road, of much higher quality than other local roads, and no road sign. This  naturally piqued my curiosity. I drove down it and came to all these forboding warning signs, akin to "Turn back or we shoot!" I turned back, and naturally have been asking people: What the heck is down there? 11/24/97

Several responses were provided. Here are some samples.

: The mystery road you spoke of leads to what is known as the "Big Hole" by the  locals. It is a top secret government location. I had a friend in high school whose dad worked there, but he wasn't allowed  to tell his family what he did at work. If he was asked where he worked he would say he ran a vending route or something.  The most he told my friend was that the government has a lot of computers and they have to have a way to communicate with each other.

A friend of mine at LC Williams Oil Co. told me that it is in fact a communications hub. When it was built he had to haul fuel for the heavy equipment to the site. He had to have a security clearance for that. He went into the building after it was done. I think he said it was three stories, all underground. He said there is a lot of kerosene stored under there (about  100,000 gallons) to run the place on generators if they need to. 11/26/97

: It is known locally as "Big Hole Road" because it has a secret underground facility at the end of it which is thirteen  stories deep. It is a defense communications facility operated under contract by AT&T, I believe. It has been there for over  twenty years. But don't tell anyone about it; it is a secret. 11/26/97

: The road off Mt Gilead goes to the "The Big Hole." It is a communications facility operated by AT&T for defense contracts.   I understand that the facility is used as a base for worldwide communications. All the buildings are underground and,  apparently, no one in Chatham County government knows exactly how big the facility is, or what exactly it contains. The  Planning Department has been told that it is only communications equipment and there are not missiles or other weapons on-site. The road into the facility apparently also has a anti-tank barricade that can be raised to block the road. Pittsboro Mayor Chuck Devinney retired last year after working there for several years. 11/26/97