you will give time to the company, work when they say you need too-with or with out compensation, work long hours during outages-with or with out compensation-
regular time periods- planning for next outage, day to day employee problems, shift schedules, pm logs- you get rated on how much of a backlog you have, emergent work-if the utility is proactive this is undercontrol-if they run it till it breaks for max profit- its day to day.
make sure the salary is high enuff so that when the techs make a whole lot more money than you do because of OT- you can deal with it.
the stress level is the same for all line supervisors- don't trip the plant, is this on the schedule, send people to training but get the job done any way etc, build cases on the slugs, and so on...