RAPID: Turning a Lake Sinkhole Event into Natural/Man-Made Tracer Experiments and Data Collection Campaign for Advanced Understanding of Karst Hydrogeology and Solute Transport

Florida State University, Tallahassee FL

Investigators

Abstract

Although lake drainage into sinkholes is common occurrences in karst systems, little is known about the relationships among lake water, groundwater, spring water, and river water. The continuous drainage of a large amount of lake water and water-contained contaminants into lake sinkholes can be viewed as a natural tracer experiment. If the contaminant concentrations are monitored in downgradient karst springs and rivers, the lake sinkhole drainage can be used to gain knowledge about the transport of water and contaminants. To test this, the project will use a man-made dye tracer along with water chemistry measurements to in an actively draining lake sinkhole. The dye tracer and water chemistry will be monitored and measured in the lake, the upper Floridan aquifer, karst springs, and rivers. Results from this project will be shared with the Florida State Geological Survey and environmental management agencies. This project examines the hydrologic connection among lake drainage via sinkholes, springs, and estuaries in a karst system. A dye tracer experiment will be used to calculate the transit time from an actively draining lake sinkhole to downgradient springs and rivers. To evaluate if environmental tracers or contaminants can be used as surrogates for dye tracer experiments in karst systems, chromophoric dissolved organic matter measurements will be taken in conjunction with the dye tracer. The results of this study and the associated methods development may be applied to many other karst systems in the U.S. The PIs will collaborate with the Florida State Geological Survey and their results will be shared with state government water resources and environmental management agencies. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.