There is always a maneuver brigade designated to respond to emergencies, it rotates through available units annually. FEMA (Which now falls under HSA) after all has the power to tap every other executive agency for support in emergencies, which includes DOD forces, a quite foreseeable need and so a brigade is always identified for this. As referred to above, that was what all that pointless fearmongering over the 3ID Brigade was awhile back.
That's entirely different from being mobilized for it (And the 82d is supposed to be about as 'Mobilized' as it can get already, since it's an active component unit). An active component unit would only get 'Alerted for' or 'Deployed on' a mission, and anybody above the rank of E-nothing really ought to have enough sense to know that getting alerted for a mission on a WARNO or FRAGO doesn't even remotely mean you're about to go do it, it just tells you that it's a contingency mission you might have to do, so you will be situationally aware.
I don't want to waste the bandwidth pulling this down to watch, but if it's some 82d kid panicking after getting his mission brief, it's complicated and well outside his daily frame of reference, so I'd discount it accordingly.