First maintenance job for a wastewater company, what should I expect?

I’m really excited, it is my foot in the door. Pay is meh, but ample opportunity(and incentive $$$) to learn and grow, great benefits. They were kind vague about the day-to-day because it’s so broad. Most I took away from it was I will be doing a lot of lawn maintenance over the summer, but “a little bit of everything” when the grass ain’t growing. Is there anything I could be studying up on before I start? Any pointers for a first-time maintenance guy?