.....For the jobs that had me on a well site for my entire shift (sometimes spending 10 of the 12 hours standing outside in temperatures down to -50), I went with a pair of Baffins. I hate the "big mushy clown foot" feeling....but they are the only boots that I know of that will keep your feet warm in that situation. I found that they actually worked better overall than the mukluks that the Canadian Army issues. They were heavier and wouldn't be as well suited for extended arctic operations out of a tent - but better if you get to go inside at night.
Wear nylons or a thin synthetic sock to wick the sweat away from your feet, followed by a thick wool sock. Also, make sure that there is somewhere inside the boot for the moisture from your feet to go - felt or mesh insoles tend to work well.
One other thing - take the liners and the insoles out of the boots as soon as you get back indoors, and get them hung up to dry. You comfort relies on all of that insulation being bone dry when you start your day.
