I came across this article from another forum, supposedly it was mirrored from a 2009 entry an archived, or something like that. Anyways it talks
about an expansive underground tunnel system connecting Wal-Mart in the South. Although the state's it references as being part of this tunnel system
don't include the states that had recent closings, it does mention its purpose.
"In order to further protect the homeland and ensure the safety of it's citizens in case of nuclear, biological, or chemical attack, a join venture
of the NSA, DOD, MiB, DHS, CICs, DFCS,...