Did some googling, because it wouldn't be a Snidget discussion without a link

http://www.khulsey.com/jewelry/kh_jewelry_diamond_mines_canada.html indicates the do get some stuff in by air, I thought from the show it was mostly the insanely heavy stuff or things that were hard to fly in for some reason as well as anything they have to haul out during the winter that was the main things done by truck.

Now the rigs out in the arctic ocean, I think you'd have a harder time air dropping stuff, I don't know what the biggest you can build a sea plane, so you can't land other than that in the summer, and the winter landings would be the same issues as the other air strips and you don't want a big plane going through the ice, nor do you want any of the heavy equipment airdropped onto the wrong bit of ice and breaking through. I also imagine the size of a flotation device so something dropped in the water wouldn't sink would be a lot more expensive than hazard pay for the truckers.

I imagine they have to carry pretty hefty insurance on those guys so if they die on the job someone gets a big check. Pay for hazardous jobs usually does include the risk in the factor, which is why some guys do it. They can probably make as much in a winter driving on ice as they could in a year driving on roads.