the area from which a body of water is recharged. In the Mammoth Cave region, the cave and groundwater recharge zone may be many miles from the cave itself and may include disappearing springs and sinkholes.

The area of land, including caves, sinkholes, faults, fractures and other permeable features, that allows water to replenish an aquifer . This process occurs naturally when rainfall filters down through the soil or rock into an aquifer.

Portion of an aquifer where water enters the sub-surface through sinkholes, caves, and fractures in the rock. Term Acronym Source