I have done several approaches to minimums, and on snow covered runways. Happens alot when you fly out of dtw into all the areas of the northeast. I am not sure what happens at SA but at pinnacle you have to have a certain amount of time in the plane before you can land in certain circumstances, such as low vis, contaminated runway, high crosswind, etc... but once you have the expierence, and the captain has flown a couple legs with you, if they feel you can handle it then they should give you a shot. I wouldn't want the first time i landed on a snow covered runway to be my 1st flight out of upgrade oe. He had probably flown a couple legs with the guy and felt he was competent to do the job.