"We train harder here than in any other unit we have been in and we do that because we know we have to be ready, we're the only ones that can do it so we're prepared and it is very real," says Lt. Col. Adam W. Hilburgh, commanding officer of the battalion the largest of its kind in the U.S. military.
Allowing CNN exclusive access to a training drill underground, four members of the battalion enter a facility staged to look like it's for nuclear weapon storage.
Suited in "Level B" protective suits, chemical resistant boots and gas masks attached to oxygen tanks on their backs, they take no chances. They send a remote-controlled robot ahead to monitor radiation levels and chemical agents. The team then moves in and discover yellowcake -- a form of uranium -- a substance North Korea is believed to possess.
It is a scenario that is staged, but based on reality. "We take into account the newest intelligence to tailor our training to ensure we're ready for anything that they could possibly have or use on the battlefield," says Lt. Col. Hilburgh. Read more on edition.cnn.