We took the tour last year,,we were with HAL,,,HAL is not in charge of this portion of the trip,,if that was unclear to you (we were on a HAL cruistour). You get a box lunch that is, as stated above, pretty sad. If I recall there were chips, cheese, a few crackers, and a small thing of reindeer sausage so you could make a cracker/cheese/sausage combo. I was not about to eat Rudolph.
Trip lasted over 7 hours,,you were supplied water and they had a coffee/hot chocolate break once,,along with numerous porta-potty stops.
One more thing,,everything you eat has to be inside the bus or the bus driver will yell at you. No crumbs outside,,,disrupts the natural food chain (at least thats what he said to me when I tried to eat outside!).
Our buses (Denali tour) left at 5:30 in the morning. We arrived the night before from Anchorage,,toured Denali in the morning, then back to the train by 3 pm to finish the trip to Fairbanks. So we were up at 4:40am and arrived at hotel in Fairbanks at 9 pm,,,really long day!