Cache is located at these coordinates in front of the new nature center; it will be obvious as you approach. You’ll first need to know the colors from the three caches hidden on this property and in order; those will help you unlock the padlock on this bonus cache, though you'll have to figure out how the colors correspond to numbers. Terrain level for the actual cache would be a 1.5 except you'll need to find the other 3 caches first, hence the higher terrain rating. The woman that runs the nature center is familiar with the cache and might be able to give you a hint if she's about and you're stumped. There's ample room for trackables, and I've left one for the first to find.
Entrance to the camp is Camp K Drive located on Highway 36. Ample parking available.