I've always known it at the person who coordinates staffing as well as handled resident concerns that go above the direct-care staffs heads. They also ensure that care plans are up to date, MARs are correctly filled out, and state required documents are complete and up to date. There's a few more tasks I know I'm forgetting, however I'm unsure because our RSD had several roles.
Depends on your state, how ALFs operate, what type staff you monitor (caregivers- do they pass meds? all meds? injections? narcs?), what type patients they accept. In a lot of ALFs, they accept patients that actually need a nursing home- incontinent, can't move, unstable diabetes, etc.
It's not a sit down job. Imagine a building with maybe 200 apartements- you want to know the residents, monitor the staff that pass meds, make room visits, problem solve, handle a ton of complaints, maybe monitor a dining service. The charting is minimal. You may have to help market the place.
In general: you'll probably be paid poorly, but even though it sounds like a lot, it's a cakewalk compared to LTC. Plan on making a lot of rounds, just to keep the peace, and you'll like it, more likely than not. What the people want more than anything is to feel as though they have a private duty nurse that they can call at anytime, they like that sense of safety. If you get to know them all, and visit them all routinely, and treat your caregivers with respect- you'll save yourself and the staff a million call lights. Mostly, they are lonely old people waiting for their next human contact.