A diver that day noted loose plant debris moving at the orifice indicating outward flow. Outflow also tended to gently push the diver from the hole as he tried to enter. A gentle boil was noted at the pool surface over the orifice. When spring flow is high, the pool is clean and clear, but when flow is low, murky lake water may cloud the pool. Analyses by U.S. Geological Survey.
Units are in milligrams per liter unless otherwise indicated.