We camped at site 16 in the primitive campground.  It was our first time, and we picked that site because it was the end of the road so we figured it would be quiet.  Heads up to other first timers:  there's a lookout at the end of the road with benches, etc. that's quite popular for folks to drive/bike/walk down to. The sites themselves were pretty small, and they are *extremely* close together. It felt like we could probably have a conversation through our tent with our neighbors.

The park ranger was extremely nice and helpful, and the views from the campsite were pretty. We paddled the long slough water trail; the put in is right down the road from the primitive campsites, which is convenient.