Found black North Face backpack near Crab Orchard National Wildlife Refuge containing a water bottle, notebooks, and a blue pencil case.

I found this black North Face backpack last Saturday while hiking near the Crab Orchard National Wildlife Refuge in Southern Illinois. It’s a bit muddy, and it seems like it may have fallen off someone's back during their excursion. Inside, it has a water bottle, a couple of notebooks, and a blue pencil case. I’d love to return it to its owner, so if you think it might be yours, please describe some of the contents to confirm.