This cache is on the Rust Bucket Trail. This trail is 1.7 miles long, mostly downhill; there are trail maps at the parking location. There is a very nice overlook of the Cahaba River below. You are looking for a pill bottle placed in a stump. Warning: Cell phone reception is poor in the Cahaba River Park.
4/16/2020: When I first scouted out the area, the stump seemed a wonderful location. Later when I came to place the cache, I discovered the stump was not hollow as I had expected, but put the cache there anyway. I am not surprised that it went missing. The cache is now 20ft to the west under a small rock ledge.