What happens when the pass closes?

We just came across Donner summit the other day during the storm (the 4th) We were headed eastbound out of California and were stopped just before Baxter. Luckily we were able to take an exit, turn around, and get a hotel for the night. Obviously you guys can't just flip a bitch. So, what happens to you guys? Do you have to sit on the pass in your truck and wait? If you're lucky enough to be stopped where you have access to an exit, do you turn around and go back to the closest town? I'm just thinking about all the diesel that gets burned by all those vehicles sitting there idling. Obviously it's a huge problem for you guys. I'm just curious how you go about dealing with it.

Huge respect to you folks, as always.