Ed_S: It's just as dodads said - the cache is gone, and there was a note left where the cache was that said "Game Over" so based on that, I'll replace this cache in another location. If it was on private property, it's not posted as such, nor is there any indication that the park property ends anywhere. I'll make sure the replacement is on park property (although I still think the last one probably was, too!)
Thanks for finding this one, and stand by for the next one!
Ed_S