I really need to watch the film again if a Uranium grenade was set off against the McClanes.
From my memory the area was clean except for the area within the vault that held the Uranium.
The enemy cleaned it and proceeded actions to remove the Uranium.
The McClane duo arrived and snuck in to retrieve the target. But turned out to be a traitor. They then fought their way out and sealed the deal.
Oh well I guess a reviewing is necessary.
Though flying through the air in a small fridge after being within a nuclear explosion and landing on some landmass and falling out clean as a whistle is pretty epic on the durability levels.