Acknowledgments

J. Jackson, J. Choi, and E. Nemeth assisted with sample collection. S. Krupa of the South Florida Water Management Department provided logistical support for our field efforts. In the laboratory, E. Nemeth, K. Randle, and C. Roland assisted with analyses. T. Kraemer and G. Jolly provided radon production rate measurements and lab space for other analyses. M. Doughten assisted with dissolved ion analyses. P. Swarzenski, J. Cable, D. Siegel, and an anonymous reviewer provided comments that helped to improve the manuscript.

Funding from the U.S. Geological Survey’s National Research Program and Place-Based Studies Program, and from the South Florida Water Management District supported this research. This work was performed while J.M.K. held a National Research Council Research Associateship Award at the U.S. Geological Survey.