Just upstream a short ways from the confluence of Peppermint Creek is Peppermint Falls. This is a classic Forks of the Kern side stop and is very much worth the visit. Park your rafts upstream of the creek and you’ll find the trail. The waterfall is approximately 600 feet from the river.
Notably, Peppermint Creek has a more famous waterfall outside of the Forks canyon that can be accessed via a short and popular hike. More info here.