They say all OT is optional, but understand if you don't pull your share your co-workers will not be happy. I work as little OT as I can. My supervisor has been good to me in that respect. No, these jobs wil not lead to a permanent position. You do have to ability to find permanent work once you are here or before you get here. Check this site for employers in the Oak Ridge area. There are a few companies that don't list here, such as Duratek and Pangea.