The posted coordinates are the Minneska Springs. Use the trailhead to access. Check out the nearby Earthcache GC17P6G. This bonus is one of two bonus caches for the Waukesha Spring Remnant Lab cache - you will get coordinates after answering the question for the Minneska Springs lab cache.
The cache is not at the posted coordinates.
You must find the Minneska Springs lab cache to obtain coordinates to this cache.
The Adventure Lab can be found by downloading the mobile app from Groundspeak.
The hyperlink to the Waukesha Spring Remnant is here: Waukesha Springs Remnants