There's the CPS staff - rangers, admin, groundskeepers, maintenance, program directors, etc. Then there's a revolving group of people - biologists, botanists, soil scientists, environmental scientists, GIS specialists, archaeologists, grad students and fellows in all of the above - who spend varying amounts of time at the park as their work requires.
I've explained before in this thread that there are two house-type buildings just adjacent to the campground which are used by these workers - you can see one of them just behind the fence at Campsite 39
here. The other is just out of sight behind the trees. To the right of the house, you go up a slight hill and there's a maintenance yard with garage buildings and equipment.
(I wrote a detailed report of my July excursion to the park and campground; you can read that
upthread.)