The noticeboard reads:

DEEP PASSAGE

Ripples on the surface of the pool mark the outlet of a great spring shaft. Ever since SCUBA was invented, divers have been drawn down into this underground passage. They enter at the cross logs and descend against the rising current. At 100 feet, the shaft opens into a round chamber. Far from being empty, this dark room is littered with debris—both man-made and natural. Railroad spikes and parts of cars have been seen amidst old logs and fossil-bearing rocks.

Cork Rock partially blocks the vent of a shaft which continues directly downward from the chamber. The strong flow and great pressure at that depth prevent divers from progressing further toward the unknown source of Blue Spring.