Mutant Future Big Sky
Lone Mountain Bunker Colony
In ancient times some people were lucky enough to make it to a shelter before the cataclysm. Your ancestors were just such fortunates. They were able to seal themselves in a fallout bunker (it is not a Vault, do not even think of calling it a Vault!) deep in the middle of Lone Mountain. The company that built the shelter never thought anyone would actually use it, and after barely a generation, the food stockpiles spoiled, and the bunker doors had to be opened.
Luckily, the small valley at the base of Lone Mountain received very little radiation and the bunker-dwellers were able to start a small colony. Those chosen to work outside the bunker were referred to as colonists, and were no longer allowed back except for very special circumstances.
Those inside continued to work in the high end jobs (medical, science, administration, etc.). After several generations more and more of the technology inside the bunker broke down and a greater part of the population moved outside. Mutations from the ambient radiation began to creep into the colonists population, although those who remained in the bunker were all pure strain humans.
For a few more generations things continued peacefully and the bunker and colony prospered, adopting a strict policy of isolationism. No one was even allowed to explore the surrounding area. Soon, the outside world began to intrude upon Lone Mountain. First, Mutant animals and other beasts occasionally came close to the settlement and were driven away. Next a few humans and mutated humans began to find the settlement. Most of those were dealt with, either with an offer to join the colony or a swift and deadly response.
Recently though, it has become obvious that a continued policy of isolationism could be a very dangerous path. The Bunker Council, with the blessing of The Administrator, has decided to send a few small groups out into the world to explore, observe and report back what they find. You are part of just such a group.