I'm going to throw my 2 cents in and say it might be FEMA.Nac FFF
Are you near Anniston? I know there is a big FEMA/Joint Training Facility there. I did some COBRA training there in a past life. Word on the street is that there is a on-site Harris P25 or EDACS system there that really likes to crash when it gets overloaded during big exercises. TT
The frequency is an FAA and NASA allocation, but the Army Corps of Engineers have been known to use it as well.
The $FFF NAC is one I've never actually seen used before…